US3763663A

US3763663A - Pneumatic powered diaphragm pump system for heat transfer

Info

Publication number: US3763663A
Application number: US00276787A
Authority: US
Inventors: R Schlichtig
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-07-31
Filing date: 1972-07-31
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09

Abstract

A pneumatic diaphragm pump system is employed for converting energy from gaseous power fluid to pump refrigerant vapor for transferring heat. An oscillating liquid column provides inertia for associated diaphragms so that with sequencing valves a cycle of operation is set up in which expansion of the enclosed gaseous power fluid can efficiently transmit energy to the liquid column to be used to compress refrigerant vapor. Means is provided to protect from liquid hammer effect and to allow effectively unequal volume displacement of refrigerant vapor and gaseous power fluid so that large expansion ratios can be used with the gaseous power fluid.

Description

United States Patent [191 Schlichtig PNEUMATIC POWERED DIAPHRAGM PUMP SYSTEM FOR HEAT TRANSFER [76] Inventor: Ralph C. Schlichtig, 11212 3rd. St.,

Seattle, Wash. 98168 [22] Filed: July 31, 1972 [21] Appl. No.: 276,787

Related U.S. Application Data [63] Continuation-impart of Ser. No. 148,723, June 1,

[52] U.S. Cl 62/498, 62/116, 62/118, 62/238, 62/467, 62/513, 62/467, 62/501,

[51] Int. Cl. F25b 1/00 [58] Field of Search 62/116, 501, 238, 62/467, 498, 513, 118; 417/395, 104, 240

[56] References Cited UNITED STATES PATENTS 1,508,833 9/1924 Wlber ..62/501 5/1936 Holyfield ..62/501 Oct. 9, 1973 2,212,281 8/1940 Ullstrand 417/395 X 2,772,543 12/1956 Berry 62/501 2,637,981 5/1953 Russell... 62/501 3,699,779 10/1972 Schlichtig 62/324 Primary Examiner-William J. Wye Att0rneyKenneth W. Thomas [5 7] ABSTRACT A pneumatic diaphragm pump system is employed for converting energy from gaseous power fluid to pump refrigerant vapor for transferring heat. An oscillating liquid column provides inertia for associated diaphragms so that with sequencing valves a cycle of operation is set up in which expansion of the enclosed gaseous power fluid can efficiently transmit energy to the liquid column to be used to compress refrigerant vapor. Means is provided to protect from liquid hammer effect and to allow effectively unequal volume displacement of refrigerant vapor and gaseous power fluid so that large expansion ratios can be used with the gaseous power fluid.

17 Claims, 18 Drawing Figures PATEN'IE um 9191 SHEET 2 0F 9 llllllllllll W g3 PATENTEDUCI 9mm 3 sum 3 OF 9 PATENTEUBBT elm I 6.163.663

SHEET u 0F 9 lllllllllllll PATENTEDHET 1 15 3,763,663

SHEET 9 BF 9 1L zg T L L 4 PNEUMATIC POWERED DIAPHRAGM PUMP SYSTEM FOR HEAT TRANSFER This invention relates to improvements in a pneumatic powered diaphragm pump system as applied to a heat transfer system such as used for refrigeration, air conditioning or heat pumping.

In this application, as distinct from U.S. Pat. application Ser. No. 148,723, means isprovided for an enclosed liquid column to move rapidly back and forth with substantially the same inertia in both directions, transmitting kinetic energy from a gaseous power vapor diaphragm compartment to a corresponding refrigeration vapor diaphragm compartment variously oriented with respect to the gaseous power vapor diaphragm compartment, thus simplifying the apparatus. Provision is made for minimizing energy loss from liquid hammer effect and for controlling the apparatus so as to allow considerable flexibility of operating conditions. The present invention permits a power vapor diaphragm compartment and a refrigerant vapor diaphragm compartment to be located on the same end of the liquid column thus providing greater flexibility in system configuration and application. In the present invention valving problems are also simplified. As in the case of US. Pat. application Ser. No. 148,723 means is provided for adiabatic expansion of gaseous power fluid in the power vapor diaphragm compartments, and fluorocarbons can be readily used for both power fluid and refrigerant. In the present application one embodiment is shown and described in which two separate power fluids such as steam and a fluorcarbon can be used so as to provide double use of supplied heat by higher and lower temperature stages, with resulting higher coefficient of performance. In addition, water used for power fluid in this two stage manner need not condense at subatmospheric pressure and thus requires but little superheating. In several embodiments of this invention a simpler and less expensive means of preheating, liquid power fluid is provided, which may either replace or supplement the preheating means illustrated in US. Pat. application Ser. No. 148,723. In at least one'embodiment of this invention afluorocarbon of relatively high boiling point such as trich'lorotrifluoroethane (Rll3) can be used for the power fluid, thus allowing the power fluid to operate with a larger expansion ratio to thereby achieve a higher coefficient of performance for the heat transfer system.

Therefore, anobject of this invention is to provide an efficient and relatively inexpensive diaphragm type heattra'nsfer system that can be driven by a. variety of gaseous fluids.

Another object of this invention mally powered heat transfer system that can be powered' in two stages by two different fluids of different boiling points.

Still another object of this invention is to provide a thermally powered heat transfer system using diaphragms and a liquid column in such a manner that there can be effectively unequal volume displacement with respect to the refrigerant vapor and the power vapor to thus permit the use of a minimum amount of power vapor required to supply the required amount of energy for compressing refrigerant vapor to thereby increase the efficiency of the heat transfer system.

A further object of thisinvention is to provide a thermally powered heat transfer system having a large degree of flexibility with respect to operating conditions.

is to provide a ther- Another object of this invention is to provide in a heat transfer system using a pumping diaphragm hydraulically coupled to a liquid column, over-pressure protection means to protect the system from the over pressure that would normally occur at the ends of the liquid column due to the liquid hammer. effect.

Other objects of this invention will become apparant from the following description when taken in conjunction with the accompanying drawings in which:

FIG. 1a through lf are schematic diagrams of one embodiment of this invention in which six time phases of operation forone complete cycle of operation are illustrated for a diaphragm pump type of heat transfer system in which there is a power vapor compartment and a refrigerant vapor compartment at each end of a conduit enclosing a liquid column, and in which two separate supplies of gaseous power fluid of different boiling points are provided, one for each of the two power vapor compartments, which are disposed at upposite ends of the conduit enclosing the liquid column.

FIGS. 2a through 2d are schematic diagrams of another embodiment of this invention in which four time phases of operation for a complete cycle of operation are illustrated for a diaphragm pump type of heat transfer system in which two diaphragms are positioned at the same end of a conduit enclosing a liquid column, one diaphragm providing the boundary between a liquid filled compartment at one end of the liquid column and a power vapor compartment, and the other diaphragm providing a boundary between the power vapor compartment and a refrigerant vapor compartment. A third diaphragm is at the opposite end of the conduit and provides a boundary between a liquid filled compartment and a gas cushion compartment.

FIGS. 3a through 3d are schematic diagrams of another embodiment of this invention in which four time phases of operation for a complete cycle of operation are illustrated for a thermally powered diaphragm heat transfer system in which two diaphragms are disposed at the same end of a conduit-enclosed liquid column, one diaphragm providing a boundary between a liquid filled compartment at one end of the liquid column and a power vapor compartment, and the other diaphragm providing a boundary between the power vapor compartment and a refrigerant vapor compartment. A third diaphragm is disposed at the opposite end of the conduit-enclosed liquid column and provides a separating boundary between a liquid filled compartment and a second refrigerant vapor compartment that functions in conjunction with the third diaphragm as a secondary refrigerant vapor pump that is supplied with refrigerant vapor from a higher pressure source than that pressure within the main refrigerant evaporator.

FIGS. 4a through 4d are schematic diagrams of still another embodiment of this invention in which four time phases of operation for a complete cycle of operation are illustrated for a thermally powered diaphragm pump system for pumping refrigerant vapor for heat transfer. In this system there is one diaphragm at each end of a conduit-enclosed liquid column, one diaphragm providing a boundary between a liquid filled compartment and a power vapor compartment and the other diaphragm providing a boundary between a liquid filled compartment and a refrigerant vapor compartment.

Referring to FIGS. la through 1 f there areshown six time phases of operation for one complete cycle of operation of a thermally powered heat transfer and air conditioning system illustrating one embodiment of the teachings of this invention in which three working fluids are used, a power fluid such as water with higher boiling point, a second safe and nontoxic power fluid having a lower boiling point such as fluorocarbon, for example, a mixture of dichloromonofluoromethane (R-21) and dichlorotetrafluoroethane (R-ll4), and a safe nontoxic refrigerant refrigerant of still lower boiling point such as another fluorocarbon, for example, dichlorodifluoromethane (R-12) or any mixture of (R-l2) with monochlorodifluoromethane (R-22).

The heat transfer system 10 as shown has but one heat source 11 which is associated with a first and higher pressure boiler 12 containing the power fluid of higher boiling point such as water. A second boiler 14 which comprises a part of a condenser-boiler exchanger 15 supplies vaporized power fluid of lower boiling point and receives heat of condensation from a power fluid condenser 16, which also forms a part of the condenser-boiler exchanger 15 and which condenser 16 in turn receives exhausted vapor of higher boiling point power fluid which originated in the first boiler 12. The vaporized lower boiling point power fluid is condensed within an air finned condenser 18 after being used. This double staging of the

boilers

12 and 14 permits higher coefficient of performance for the heat transfer system 10, but also requires that the second power fluid of lower boiling point within the second boiler 14 will boil at a lower temperature than the temperature of exhausted vapor of higher boiling point power fluid within the condenser 16. Two

separate pumps

20 and 22 are interconnected in the heat transfer system 10 as shown so as to return the two condensed power fluids from the two power fluid condensers l6 and 18, respectively, to the two

respective boilers

12 and 14 which function as the means for supplying the power fluid in a gaseous state under the required pressure. Of course, if one does not desire to take advantage of double staging to make double use of heat, two completely independent assemblies of heat source, boiler and condenser for the heat transfer system 10 may be used or a single assembly of heat source, boiler and condenser, such as ll, 12 and 18, may be used for the heat transfer system 10. In order to preheat liquid power fluid before it is returned to the boiler 14 from the condenser 18 a heat exchanger 24 is interconnected between the pump 22 and the boiler 14 by conduit means 26. Means for condensing and for reevaporating the refrigerant fluid includes an air-finned refrigerant evaporator 28 and associated conduit means 30, and an air-finned refrigerant condenser 29.

In order to pump refrigerant vapor from the refrigerant evaporator 28 and return compressed refrigerant vapor through conduit means 30 and 32 and the heat exchanger 24 to the refrigerant condenser 29, diaphragm pump means 34 is provided. In operation, the diaphragm pump means 34 receives its energy for pumping from the gaseous power fluid supplied by the boilers l2 and 14.

The diaphragm pump means 34 includes a conduit 36 enclosing a liquid colum 38; pneumatic driving means 40 including one separate power vapor compartment 42 associated with one end of the liquid column 38 through a flexible power vapor diaphragm 44 which is hydraulically coupled to the liquid column 38 by means ofa hydraulic coupling 46 to thus couple the inertia of the liquid column 38 to the power vapor diaphragm 44, and a second separate power vapor compartment 48 associated with the other end of the liquid column 38 through a flexible power vapor diaphragm 50 which is hydraulically coupled to the liquid column 38 by means of a hydraulic coupling 51 to thus couple the inertia of the liquid column 38 to the power vapor diaphragm 50, the power vapor compartments 42 and 48 being so disposed in cooperative relationship with the means for supplying a power fluid in a gaseous state, namely the boilers 12 and 14 respectively, that the gaseous power fluid provides energy for oscillating the liquid column 38 over substantially the same path and with substantially the same inertia in both directions of such oscillation; one separate refrigerant vapor compartment 52 associated with one end of the liquid column 38 and having a boundary in common with the power vapor compartment 42, the boundary being formed by a flexible boundary diaphragm 54; and a second separate refrigerant vapor compartment 56 associated with the other end of the liquid column 38 and having a boundary in common with the power vapor compartment 48, the latter boundary being formed by a flexible boundary diaphragm 58, and each of the separate refrigerant vapor compartments 52 and 56 being disposed in cooperative relationship with the refrigerant evaporator 28 so as to receive refrigerant vapor from the refrigerant evaporator 28 and so that upon oscillation of the liquid column 38 energy originating from expansion of gaseous power fluid within the power vapor compartments 42 and 48 is transmitted from the liquid column 38 to compress the refrigerant vapor received in the respective separate refrigerant vapor compartment 56 or 52 toward which the liquid column 38 is moving and to expell compressed refrigerant vapor to the refrigerant condenser 29.

The two refrigerant vapor compartments 52 and 56 have

intake check valves

60 and 62, respectively, for controlling the flow of refrigerant vapor from the refrigerant evaporator 28 through the conduit means 30 and into the respective refrigerant vapor compartments 52 and 56, and respective

discharge check valves

64 and 66 for controlling the flow of refrigerant vapor from the respective refrigerant vapor compartments 52 and 56 through the conduit means 32 and the heat exchanger 24 to the air-finned refrigerant condenser 29 for condensing. Condensed refrigerant flows from the air-finned refrigerant condenser 29 to the air-finned refrigerant evaporator 28 through regulated conduit means 68 since the pressure in the refrigerant evaporator 28 is lower than the pressure within the refrigerant condenser 29. As shown, each of the hydraulic couplings to or liquid filled

compartments

46 and 51 includes a conduit which diverges from the diameter of the liquid column 38 to effect a conversion of velocity energy to pressure energy in a manner well known to the diffusor art. In the next three embodiments shown and described herein the corresponding hydraulic couplings likewise diverge to accomplish the same function.

Sequencing valve means 70 is provided for controlling the mode of operation of the diaphragm pump means 34 with respect to each end of the liquid column 38 by permitting a flow of vaporized power fluid from the

boilers

12 and 14 to the respective power vapor compartments 42 and 48 during a different time phase of operation for each of the

power vapor comportments

42 and 48 when the inertia of the liquid column 38 is offering sufficient pressure opposition to the vaporized power fluid flowing into the particular respective

power vapor compartment

42 or 48 that at another time phase of operation for each of the power vapor compartments 42 and 48 substantially adiabatic expansion of such vaporized power fluid can take place and will yield work sufficient to further increase the velocity and therefore the kinetic energy of the liquid column 38 so as to substantially adiabatically compress refrigerant vapor in the respective refrigerant vapor compartments 56 and 52 associated with the opposite end of the liquid column 38, and by permitting during still a different time phase of operation for each of the separate power vapor compartments 42 and 48 a flow of expanded vaporized power fluid from each of the respective separate

power vapor comparments

42 and 48 to the respective

power fluid condensers

16 and 18 for condensing of the expanded vaporized power fluid. The sequencing valve means 70 includes a power vapor inlet valve 72 and a power vapor exhaust valve 74 associated with the power vapor compartment 42 and a power vapor inlet valve 76 and a power vapor exhaust valve 78 associated with the power vapor compartment 48.

An energy recovering over-pressure protection means 80 is shown associated with the

hydraulic couplers

46 and 51 at the respective both ends of the liquid column 38 so as to serve both ends of the liquid column 38 and reduce energy loss at either end that would otherwise be caused by liquid hammer effect. The overpressure protection means 80 includes a movable parittion 82, specifically a diaphragm separating a liquid receiving compartment 84 from a pressurized gas filled compartment 86 that is pressurized, for example from the higher pressure boiler 12 containing the power fluid of the highest boiling point. The liquid receiving compartment 84 of the over-pressure protection means 80 is connected by means of

conduits

88 and 90 to the

hydraulic couplings

46 and 51 respectively, so as to receive liquid from the respective

hydraulic couplings

46 and 51 at those times when the hydraulic pressure in the respective

hydraulic coupling

46 and 51 exceeds the pressure within the pressurize gas filled compartment 86. A control mechanism 92 is sensitive to the pressure difference existing in ,a conduit means 94 and the conduit 88 so that it actuates a check valve 96 open when the pressure rises in the conduit means 94 to equal to the pressure in the conduit 88 to thus allow the expulsion of the received liquid from the liquid receiving compartment 84 through the conduit 88 to the hydraulic coupling 46 during the time phase of operation when the vaporized power fluid is permitted to flow from the boiler 12 to the power vapor compartment 42. As an alternative, the control mechanism 92 can be directly mechanically linked to the power vapor inlet valve 72 since check valve 96 must open during the time valve 72 is open and must operate as a check valve at all other times. There is also a check valve 98 in the conduit 90 from the hydraulic coupling 51.

In order to provide a reference plane for the diaphragm 82 of the over-pressure protection means 80 a liquid-passing rigid perforated disk 99 is provided. The disk 99 functions as a reference stop for the diaphragm 82 and prevents it from forcing an unwanted surplus of liquid to the hydraulic coupling 46.

The operation of the energy storing over-pressure protection means will be briefly described. Any surplus energy of the liquid column 38 building up excess pressure in the hydraulic coupling 46 will force liquid through the conduit 88 and the check valve 96 and into the liquid receiving compartment 84 so that the diaphragm 82 is'moved upward against pneumatic pressure, thus storing energy. Likewise if excess pressure builds up in the hydraulic coupling 51 by surplus energy of the liquid column 38 moving toward the end having the hydraulic coupling 51, liquid is forced through the conduit and the check valve 98 into the liquid receiving compartment 84 and also moves the diaphragm 82 upward to thus store energy as before.

The operation of the heat transfer system 10 of FIGS. la through If will now be described. Each complete cycle of operation of the heat transfer system 10 has six time phases. The schematic diagrams of each of the FIGS. la through If illustrate respectively the positioning of the valve components and the direction of fluid flow for the particular time phase of operation being illustrated. Arrows also indicate the direction of motion of the several flexible diaphragms.

Referring to FIG. la illustrating the first of the six time phases of operation, at the beginning of this first time phase of operation both the

diaphragms

44 and 54 are positioned in their uppermost position within the diaphragm pump means 34 and the

flexible diaphragms

50 and 58 are positioned in their lowest position within the diaphragm pump means 34. FIG. lla shows the position of

diaphragms

44, 50 and 58 after some movement has taken place. As shown, the

power vapor valves

74, 76 and 78 are closed and the power vapor inlet valve 72 is open to permit the passage of vaporized power fluid from the boiler 12 through the valve 72 and into the power vapor compartment 42 to pressurize the power vapor compartment 42; and the

check valves

60, 62, 64, 66 and 98 are closed. At this time the control mechanism 92 actuates the check valve 96 to the open position to permit the vaporized power fluid. within the gas filled compartment 86 of the over-pressure protection means 80 to effect a downward displacement of the diaphragm 82 and thus a displacement of liquid from the liquid receiving compartment 84 through the open check valve 96 and the conduit 88and into the hydraulic coupling 46. Thus, the'pressure of the vaporized power fluid within the power vapor compartment 42and within the gas filled compartments 86 of the energy recovering over-pressure protection means 80 both contribute energy required for acceleration of the liquid column 38 toward the hydraulic coupling 51, which energy begins to be used to move the contacting

diaphragms

50 and 58 upwardly toward the top of the diaphragm pump means 34 to thereby begin substantially adiabatic compression of the refrigerant vapor within the refrigerant vapor compartment 56. The pressure of the vaporized power fluid within the gas filled compartment 86 continues to aid in effecting this acceleration of the liquidcolumn 38 until the diaphragm 82 comes down to rest against the stop disk 99. Even after the diaphragm 82' reaches this limiting position the pressure of the vaporized power fluid within the power vapor compartment 42 continues to effect an acceleration of the liquid column 38 and to initiate sub stantially adiabatic compression of the refrigerant vapor within the refrigerant vapor compartment 56. During this limited time phase of operation and before the liquid column 38 has acquired its maximum velocity, the inertia of the liquid column 38 offers sufficient opposition to the pressure of the vaporized power fluid in the vapor compartment 42 that the vaporized power fluid within the power vapor compartment 42 retains a large amount of potential energy by virtue of its pressure, heat content and volume that during the next time phase of operation substantially adiabatic expansion of the vaporized power fluid which entered the power vapor compartment 42 during the first time phase of operation will yield work sufficient to further increase the velocity and therefore the kinetic energy of the liquid column 38 so that substantially adiabatic compression of the refrigerant vapor within the refrigerant vapor compartment 56 can take place completely and the refrigerant vapor can also be displaced from the refrigerant vapor compartment 56 during the second time phase of operation.

Referring to FIG. 112 there is illustrated the positioning of the various valve components and the fluid flow for the heat transfer system 10 for the second time phase of operation. During the second time phase of operation for the heat transfer system 10 all the

power vapor valves

72, 74, 76 and 78, of the sequencing valve means 70,'are closed, and the

check valves

60, 62, 64, 96 and 98 are closed; but the refrigerant vapor discharge check valve 66 is open during the latter part of this second time phase of operation after the pressure in the refrigerant vapor compartment 56 rises above that in the condenser 28. The liquid column 38 continues to move in the direction indicated, receiving energy from substantially adiabatic expansion of the vaporized power fluid that flowed into the power vapor compartment 42 during the first time phase of operation, and delivering energy to substantially adiabatically compress refrigerant vapor within the refrierant vapor compartment 56 by communicating force on the diaphragm 58 through the adjacent diaphragm 50. During the latter part of this second time phase of operation, when the pressure within the refrigerant vapor compartment 56 exceeds the vapor pressure within the refrigerant condenser 29. refrigerant vapor is expelled from the refrigerant vapor compartment 56 and through the heat exchanger 24 to the refrigerant condenser 29. In the heat exchanger 24 compression heat carried by refrigerant vapor is transferred to preheat power fluid flowing to the boiler 14 and also cool the refrigerant vapor flowing to the refrigerant condenser 29. Liquid refrigerant that is condensed in the refrigerant condenser 29 flows at a restricted and regulated rate through the regulated conduit means 68 to the refrigerant evaporator 28.

Referring to FIG. 10 there is illustrated the positioning of the various valve components and the direction of fluid flow for the heat transfer system 10 for the third time phase of operation. During this third time phase of operation the

power vapor valves

72, 76 and 78 are closed and the power vapor exhaust valve 74 is open, and the

check valves

62, 64, 66 and 96 are closed while the

check valves

60 and 98 are open. As shown, during this third time phase of operation the

diaphragms

50 and 58 reach the uppermost position withing the diaphragm pump means 34 and any residual velocity of the liquid column 38 at the end of its oscillation in one direction is rapidly decellerated, causing pressure to rise in the hydraulic coupling 51 so that any corresponding residual energy of the liquid column 38 forces a proportional amount of liquid through the conduit 90 and the check valve 96 into the liquid receiving compartment 84 of the over-pressure protection means to move the diaphragm 82 upward against pneumatic pressure in the gas-filled compartment 86, thus recovering the energy. During this third time phase of operation the power vapor exhaust valve 74 is open to the power vapor condenser 16, reducing the pressure in the power vapor compartment 42 so that refrigerant vapor from the refrigerant evaporator 28 pushes through the check valve 60 to push the diaphragm 54 downward to the diaphragm 44, thus enlarging and filling the refrigerant vapor compartment 52 with refrigerant vapor while expelling the expanded vaporized power fluid from the power vapor compartment 42 through the power vapor exhaust valve 74 to the power fluid condenser 16 for condensing.

The first power vapor that is discharged from the power vapor compartment 42 has sufl'iciently high boiling point and thus high enough condensing temperature at exhaust pressure that it will condense in the power fluid condenser 16 at a sufficiently high temperature that the heat of condensation liberated in the condenser-boiler exchanger 15 will vaporize the second power fluid in the boiler 14 at sufficient operating temperature and pressure. For example, if R-22 is chosen for the refrigerant it would have a normal operating pressure of Psia in the refrigerant evaporator 28 and commonly reach a pressure of 250 Psia in the refrigerant condenser 29. Thus, if water is used as the first power fluid in the boiler 12 it could have a useable working pressure of 467 Psia at 460 F and could be displaced from the power vapor compartment at 85 Psia so that it would condense in the power fluid condenser l6 at 315 F, which is high enough temperature to boil a second power fluid such as 33.8 percent mixture of R-ll4 in R-2l at 280 F and pressure of 350 Psia in the boiler 14, and then condense this second power fluid in the second power fluid condenser 18 at F and 64 Psia pressure. Liquid power fluid that condenses in the power fluid condenser 16 is returned to the boiler 12 by the action of the pump 20.

Referring to FIG. 1d illustrating the fourth of the six time phases of operation only the diaphragm 58 is at the top of the diaphragm pump means 34, whereas at the beginning of this fourth time phase of operation both the

diaphragms

50 and 58 were positioned in their uppermost position within the diaphragm pump means 34 and the

diaphragms

44 and 54 were positioned in their lowest position within the diaphragm pump means 34. As shown, the

power vapor valves

72, 74 and 78 are closed, but the power vapor inlet valve 76 is open to permit the passage of vaporized power fluid from the boiler 14 of the condenser-boiler exchanger 15 through the valve 76 and into the power vapor compartment 48 to pressurize the power vapor compartment 48; and the

check valves

60, 62, 64, 66, 96 and 98 are closed. The diaphragm 54 is resting against the diaphragm 44. During this fourth time phase of operation the pressure of the vaporized power fluid within the power vapor compartment 48 effects an acceleration of the liquid column 38 toward the hydraulic coupling 46 to thus move the

diaphragms

50, 44 and 54 in the direction shown by the arrows. During this time phase of operation and before the liquid column 38 has acquired its maximum velocity the inertia of the liquid column 38 offers sufficient opposition to the pressure of the vaporized power fluid flowing into the power vapor compartment 48 that the vaporized power fluid within the power vapor compartment 48 retains a large amount of potential energy by virtue of its pressure, heat content and volume that during the next time phase of operation substantially adiabatic expansion of the vaporized power fluid entered the power vapor compartment 48 during the fourth time phase of operation will yield work sufficient to further increase the velocity and therefore the kinetic energy of the liquid column 38 so that substantially adiabatic compression of the refrigerant vapor within the refrigerant vapor compartment 52 can take place during the fifth time phase of operation and the refrigerant vapor can be displaced from the refrigerant vapor compartment 52 during the first part of the fifth time phase of operation. Thus, during this fourth time phase of operation the vaporized power fluid admitted to the power vapor compartment 48 accelerates the liquid column 38 in the return direction of its cyclic oscillation. During this fourth time phase of operation the time that the power vapor intake valve 76 is open must be definitely limited so that the amount of power vapor admitted can expand substantially adiabatically to approximately stable discharge pressure during the fifth time phase of operation. Initial substantially adiabatic compression of the refrigerant vapor within the refrigerant vapor compartment 52 takes place during this fourth time phase of operation.

Referring to FIG. le there is illustrated the positioning of the various valve components and the fluid flow for the heat transfer system 10 for the fifth time phase of operation. During the fifth time phase of operation for the heat transfer system 10 all of the

power vapor valves

72, 74, 76 and 78 of the sequencing valve means 70 are closed, and al 0 the

check valves

60, 62, 66, 96 and 98 are closed, while the check valve 64 is open during only the later prt of the fifth time phase of operation (as illustrated in flG. le). The liquid column 38 continues to move in the directions indicated, receiving energy from substantially adiabatic expansion of the vaporized power fluid that flowed into the power vapor compartment 48 during the fourth time phase of operation and continues to deliver energy to substantially adiabatically compress refrigerant vapor within the refrigerant vapor compartment 52 by communicating force on the diaphragm 54 through the contacted diaphragm 44. During the later part of this fifth time phase of operation, when the pressure within the refrigerant vapor compartment 52 exceeds the pressure within the refrigerant condenser 29, refrigerant vapor is expelled from the refrigerant vapor compartment 52 and through the heat exchanger 24 to the air-finned refrigerant condenser 29. In the heat exchanger 24 compression heat carried by compressed refrigerant vapor is transferred to preheat power fluid flowing to the boiler 14 and also cool the refrigerant vapor flowing to the air-finned refrigerant condenser 29. Liquid refrigerant that is condensed in the refrigerant condenser 29 flows at a restricted and regulated rate through the regulated conduit means 68 to the refrigerant evaporator 28.

Referring to FIG. If there is illustrated the positioning of the various valve components and the direction of fluid flow for the heat transfer system 10 for the sixth time phase of operation. During this sixth time phase of operation the

power valves

72, 74 and 76 are closed and the power vapor valve 78 is open, and the

check valves

60, 64, 66 and 98 are closed, while the refrigerant inlet check valve 62 is open.'The check valve 96 is open, as shown, during a part of the time phase as will be explained. As shown, during this sixth time phase of operation the

diaphragms

44 and 54 reach their uppermost position within the diaphragm pump means 34 and any residual velocity of the liquid column 38 at the end of its oscillation in the direction toward the hydraulic coupling 46 is rapidly decellerated, causing pressure to rise in the hydraulic coupling 46 so that any corresponding residual energy of the liquid column 38 forces a proportional amount of liquid through the conduit 88 and the check valve 96 into the liquid receiving compartment 84 of the over-pressure protection means 80 to move the diaphragm 82 upward against pneumatic pressure in the gas filled compartment 86. During this sixth time phase of operation the power vapor valve 78 is open to the power fluid condenser 18, reducing the pressure in the power vapor compartment 48' so that refrigerant vapor from the refrigerant evaporator 28 pushes through the check valve 62 to push the diaphragm 58 downward to the diaphragm 50, thus enlarging and filling the refrigerant vapor compartment 56 with refrigerant vapor while expelling the expanded vaporized power fluid from the power vapor compartment 48 through the power vapor exhaust valve 78 to the power fluid condenser 18 for condensing. Liquid power fluid that condenses in the power fluid condenser 18 is returned to the boiler 14 through the heat exchanger 24 by the action of the pump 22.

Referring to FIGS. 20 through 2d there are shown four time phases of operation of one complete cycle of operation of a thermally powered heat transfer and air conditioning system 110 illustrating another embodiment of the teachings of this invention in which there is but one source of vaporized power fluid. The refrigerant may be R-l2 as in the case of the heat transfer system 10, and the power vapor must have a corresponding higher boiling point. The boiling point of the power fluid may be varied within design limits for example by mixing R-2l with trichlorotrifluoroethane (R-l13). Also steam or compressed air could be used as gaseous power fluid, in which case R-ll4 or R-21 for example could be used as the refrigerant fluid.

The heat transfer system 110 as shown has a means for supplying power fluid in a gaseous state under adequate pressure and includes the following components: a heat source 112 which supplies heat to a boiler 114, an air-finned power fluid condenser 116 for condensing expanded and returned vaporized power fluid, and a pump 118 and conduit 120 for returning condensed liquid power fluid to the boiler 114. Of course, theairfinned power fluid condenser 116 may be omitted if steam is to be the gaseous power fluid; also the boiler 114 and heat source 112 may be replaced by a tank source of compressed air. Means for condensing and for reevaporating refrigerant fluid includes an airfinned refrigerant evaporator 122 with associated liquid precooler 124 and connecting conduit 126, an airfinned refrigerant condenser 128 with associated connecting conduit 130, and a controlled conduit 132 providing a means for returning condensed liquid refrigerant from the refrigerant condenser 128 to the precooler 124 where it is precooled before flowing into the airfinned evaporator 122.

In order to pump refrigerant vapor from the refrigerant evaporator 122 and return compressed refrigerant vapor to the refrigerant condenser 128, a diaphragm pump means 134 is provided which receives its energy for pumping from the gaseous power fluid supplied by the boiler 114.

The diaphragm pump means 134 includes a conduit 136 enclosing a liquid column 138; pneumatic driving means 140 including a power vapor compartment 142 associated with one end of the liquid column 138 through a flexible diaphragm 144 which is hydraulically coupled to the liquid column 138 by means of a hydraulic coupling 146 to thus couple the inertia of the liquid column 138 to the power vapor diaphragm 144 and a diaphragm 148 coupled to the other end of the liquid column 138 by a hydraulic coupling 149 and forming a boundary between the hydraulic coupling 149 and an energy storing gas cushion space 150, the power vapor compartment 142 being so disposed in cooperative relationship with the boiler 114, which is the illustrated means for supplying power fluid in a gaseous state, that the gaseous power fluid provides energy for oscillating the liquid column 138 forward and return over substantially the same path and with substantially the same inertia in both directions of such oscillation; a refrigerant vapor compartment 152 associated with the same end of the liquid column 138 as the power vapor compartment 142 but being separated from the power vapor compartment 142 by a common boundary flexible diaphragm 158 so that during certain periods ofoperation the flexible diaphragm 158 can rest in contact with the flexible diaphragm 144 so that the energy is transmitted from the moving liquid column 138 to the refrigerant vapor enclosed within the refrigerant vapor compartment 152 in order to compress such enclosed refrigerant vapor and expell it to the refrigerant condenser 128.

The pneumatic driving means 140 comprises the power vapor compartment 142 at one end of the liquid column 138 which drives the liquid column 138 in the forward direction in its cycle of oscillation, and the energy storing gas cushion space 150 at the other end of the liquid column 138, which stores compression energy during the forward direction of oscillation with which to reverse the direction of motion of the liquid column 138 for the return portion of the oscillation so that energy delivered to the liquid column 138 in the forward oscillation is returned to the liquid column 138 in the return portion of the oscillation.

The refrigerant vapor compartment 152 of the diaphragm pumping means 134 is so disposed in cooperative relationship with the means for condensing and for reevaporating refrigerant fluid that refrigerant vapor is received from the refrigerant evaporator 122 through the conduit 126 and an inlet check valve 160, and compressed refrigerant is expelled to the refrigerant condenser 128 through a discharge check valve 168. Condensed refrigerant flows from the refrigerant condenser 128 to the refrigerant evaporator 122 through the regulated conduit means 132 such as is known in the art, as the operating pressure is greater in the refrigerant condenser 128 than in the refrigerant evaporator 122. Liquid refrigerant in the precooler 124 is in close thermal proximity with cool refrigerant vapor leaving the refrigerant evaporator 122 so that the iquid refrigerant is precooled by vapor before entering the refrigerant evaporator 122.

Sequencing valve means 170 is provided for controlling the mode of operation of the diaphragm pump means 134 by permitting a flow of gaseous power fluid from the boiler 114 to the power vapor compartment 142 during a limited time period when the inertia of the liquid column 138 is offering sufficient pressure opposition to the gaseous power fluid flowing into the compartment 142 that at another time phase of operation substantially adiabatic expansion of the gaseous power fluid within the power vapor compartment 142 takes place and yields work sufficient to further increase the velocity and therefore the kinetic energy of the liquid column 138 so as to substantially adiabatically compress refrigerant vapor in the refrigerant vapor compartment 152, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from the power vapor compartment 142 to the power fluid condenser 116 for condensing the expanded power fluid. The sequencing valve means 170 includes a power inlet valve 172, a power exhaust valve 174 and a connecting conduit means 176.

An energy recovering over-pressure protection means 180 is shown associated with the end of the liquid column 138 at which the power vapor compartment 142 is located, and functions to reduce energy loss that would otherwise be caused by liquid hammer effect when the liquid column 138 suddenly forces the diaphragm 158 against the rigid enclosure of the diaphragm pumping means 134. The over-pressure protection means 180 includes a movable partition 182, specifically a diaphragm, separating a liquid receiving compartment 184 from a pressurized gas filled compartment 186 that is pressurized from the boiler 114. The liquid receiving compartment 184 is connected by means of a conduit 188 to the hydraulic coupling 146 so as to receive liquid from the hydraulic coupling 146 at those times when the hydraulic pressure in the hydraulic coupling 146 exceeds the pressure within the pressurized gas filled compartment 186. A control mechanism 192 is sensitive to the pressure difference existing in the conduit means 176 and the conduit 188 so as to actuate a check valve 194 open when the sequencing valve 172 opens to allow the pressure to rise in the conduit means 176 to equal the pressure in the conduit 188, to thus allow the expulsion of the received liquid from the liquid receiving compartment 184 through the conduit 188 to the hydraulic coupling 146 during the time phase that the sequencing inlet valve 172 is open. A liquid passing rigid perforated disk 199 is provided to function as a reference stop for the flexible diaphragm 182. to prevent it from forcing an unwanted surplus of liquid into the hydraulic coupling 146.

The oepration of the energy-recovering overpressure protection means 180 of system 110 is similar in general to the operation of the overpressure protection means of the heat transfer system 10.

The operation of the heat transfer system of FIGS. 2a through 2d will now be described. Each complete cycle of operation of the heat transfer system 1 10 is best described if divided into four time phases. The schematic diagrams f0 each of the FIGS. 2a through 2d illustrate respectively the positioning of the valve components and the direction of flow of fluids for the particular time phase of operation being illustrated. Arrows also indicate the direction of motion of the several flexible diaphragms.

Referring to FIG. 2a illustrating the first of the four time phases of operation, at the beginning of this first time phase of operation the

diaphragms

144 and 158 are positioned in their uppermost position within the diaphragm pump means 134 so the spaces of the

compartments

152 and 142 are very small and the flexible diaphragm 148 is positioned in its lowest position within the diaphragm pump means 134. However, FIG. 2a shows the

diaphragms

144 and 148 after they have moved a considerable distance. As shown, the power vapor exhaust valve 174 is closed, but the power vapor inlet valve 172 is open during this first time phase of operation, allowing power vapor under pressure to enter the power vapor compartment 142 and act against the diaphragm 144 to accelerate the liquid column 138 in the forward phase of its oscillation which in turn begins to substantially adiabatically compress the gas within the energy storing gas cushion space 150. At the time of opening the power vapor inlet valve 172, the check valve 194 of the energy recovering means 180 is also opened by the vapor pressure communicated to the control mechanism 192. Of course, the check valve 194 could be opened by other direct linkage, not shown, with the power vapor inlet valve 172. With the check valve 194 open, pressure in the pressurized gas filled compartment 186 causes a downward displacement of the diaphragm 182 which forces liquid into the hydraulic coupling 146 which continues to contribute energy to accelerate the liquid column 138 until the diaphragm 182 is stopped by the rigid perforated disk 199, where it remains during the next two phases and toward the end of the fourth time phase of operation. During this limited first time phase of operation and before the liquid column 138 has acquired its maximum velocity, the inertia of the liquid column 138 offers sufficient opposition to the pressure of the vaporized power fluid in the power vapor compartment 142 that the vaporized power fluid within the power vapor compartment 142 retains a large amount of potential energy by virtue of its pressure, volume and heat content, that during the next time phase of operation substantially adiabatic expansion of this vaporized power fluid entering the power vapor compartment 142 during this limited time of the first phase will yield work sufficient to further increase the velocity of the liquid column 138 and thus to increase the total energy represented by the kinetic energy of the liquid column 138 and the energy stored by compressing gas within the gas cushion 150 so as to substantially adiabatically compress refrigerant vapor in the refrigerant vapor compartment 152 during the fourth time phase of operation.

Referring to FIG. 2b there is illustrated the positioning of valves and the direction of flow of fluids of the heat transfer system 110 for the second time phase of operation, during which time phase of operationall of the

valves

172, 174, 160 and 168 are closed. The liquid column 138 continuesto move in the forward phase of oscillation, receiving energy from substantially adiabatic expansion of the vaporized power fluid that flowed into the power vapor compartment 142 during the first time phase of operation, and delivering energy to substantially adiabatically compress the gas within the energy storing gas cushion 150 until all the kinetic energy of the liquid column 138 has been delivered and the pressure of this gas has reached a maximum within the energy storing gas cushion 150.

Referring to FIG. 20 there is illustrated the positioning of the various valve components and the direction of fluid flow for the heat transfer system for the third time phase of operation, during which time phase the power exhaust valve 174 is open and the power inlet valve is closed, the check valve 194 is closed, the discharge check valve 168 is closed, the inlet check valve is open and the liquid column 138 is at the pause transition between forward oscillation and return oscillation. The

diaphragms

148 and 158 at the beginning of this third time phase of operation start at their upper positions and the diaphragm 144 at its lowest position, but FIG. 2c'illustrates the diaphragm 158 after considerable movement during this time phase of operation. The open power fluid exhaust valve 174 allows expanded power vapor to flow out from the power vapor compartment 142 to the air-finned power vapor condenser 1 16 where it is condensed to a liquid and the liquid power fluid is pumped back to the boiler 114 by means of the pump 1 l8 and associated conduit 120. As expanded power vapor flows out to the power fluid condenser 116 from the power vapor compartment 142, the pressure, as determined by the power fluid condenser 116, drops within the power vapor compartment 142 so that the upward force on the common boundary diaphragm 158 is reduced to such an extent that refrigerant vapor from the refrigerant evaporator 122 pushes through teh refrigerant inlet check valve 160 into the refrigerant vapor compartment 152 and depresses the common boundary diaphragm 158 to expell the expanded power vapor from the power vapor compartment 142 until the diaphragm 158 comes to rest against the diaphragm 144.

Referring to FIG. 2d there is illustrated the positioning of the various valve components and the direction of fluid flow for the heat transfer system 110 for the fourth time phase of operation. During the fourth time phase of operation of the heat transfer system 110 both

power vapor valves

172 and 174 are closed and the refrigerant inlet valve 160 is closed, whereas the refrigerant discharge valve 168 is at first closed but opens as illustrated in FIG. 2d only during a later portion of the time phase, as will be explained. Also the check valve 194 of the energy recovering overpressure protection means is open as illustrated in FIG. 2d at a still later portion of this fourth time phase of operation as will be explained.

The compressed gas within the energy storing gas cushion 150 expands and accelerates the liquid column 138 in the return phase of its oscillation and restores energy to the liquid column 138 that had originated from pressure and expansion of vaporized power fluid in the power vapor compartment 142 during the first and second time phases of operation of the heat transfer system 110. The returning liquid column 138 communicates pressure on the diaphragm 158 through the adjacent diaphragm 144 and compresses refrigerant vapor within the refrigerant vapor compartment 152 substantially adiabatically until the pressure of the refrigerant vapor within the compartment 152 exceeds the vapor pressure within the refrigerant condenser 128, at which later time the discharge check valve 168 is pushed open as illustrated and the compressed refrigerant vapor within the compartment 152 is expelled to the air-finned refrigerant condenser 128 where it is condensed to a liquid, and the liquid refrigerant is allowed to flow back to the air-finned evaporator 122 in a regulated rate through the controlled conduit 132.

At a still later time in the fourth time phase of operation of the heat transfer system 110 when the

diaphragms

158 and 144 reach the maximum upper position, if the liquid column 138 is still moving and has residual kineticenergy, hydraulic pressure builds up in the hydraulic coupling 146 so that liquid is forced as illustrated through the conduit 188 and the check valve 194 into the liquid receiving compartment 184 of the energy recovering over-pressure protection means 180 and the diaphragm 182 is moved against the pneumatic pressure within the pressurized gas filled compartment 186, thus recovering energy and protecting the heat transfer system 110 from damage from over-pressure.

Referring to FIGS. 3a through 3d there are shown four time phases of operation of one complete cycle of operation of a thermally powered heat transfer and air conditioning system 210 illustrating another embodiment of the teachings of this invention in which two stage evaporation at different temperature and pressure levels is provided. This permits the efficient use of a refrigerant liquid with a higher specific heat for example dichlorotetrafluoroethane (R-l14) and the use of steam or trichlorotrifluoroethane (R-l13) as a power fluid, as the effective displacement volume of the combined refrigerant vapor compartments is greater than the displacement volume of the power vapor compartment.

The heat transfer system 210 as shown has a means for supplying power fluid in a gaseous state under adequate pressure and includes the following components: a heat source 212 which supplied heat to a boiler 214, an air-finned power fluid condenser 216 for condensing expanded and returned vaporized power fluid, a pump 218 and conduit 220 for returning condensed liquid power fluid to the boiler 214 and a heat exchanger 221 for preheating liquid power fluid before it is returned to the boiler 214. Of course, the air-finned power fluid condenser 216 may be omitted if steam is used as the gaseous power fluid, in addition, the heat exchanger 221 may be omitted if steam is used as the gaseous power fluid, the heat exchanger 221 may be omitted if a tank (not shown) of compressed air is substituted for the boiler 214. Means for condensing and for reevaporating refrigerant fluid includes a lower pressure airfinned refrigerant evaporator 222, a higher pressure refrigerant evaporator 224 with respective

outlet vapor conduits

226 and 227, and an air-finned refrigerant condenser 228 and connecting conduit means 230. A controlled conduit 232 allows refrigerant liquid to flow from the refrigerant condenser 228 to the higher pressure refrigerant evaporator 224 at the proper rate, and a second controlled conduit 233 allows flow of liquid refrigerant from the higher pressure refrigerant evaporator 224 to the lower pressure air-finned refrigerant evaporator 222 at such a controlled rate as to maintain the desired pressure difference and thus the desired temperature difference between the two

evaporators

222 and 224.

In order to pump refrigerant vapor from the

refrigerant evaporators

222 and 224 and return compressed refrigerant vapor to the refrigerant condenser 228, a diaphragm pump means 234 is provided which receives its energy for pumping from the gaseous power fluid supplied by the boiler 214.

The diaphragm pump means 234 includes a conduit 236 enclosing a liquid column 238; pneumatic driving means 240 including a power vapor compartment 242 associated with one end of the liquid column 238 through a power vapor diaphragm 244 which is hydraulically coupled to the liquid column 238 by means of a hydraulic coupling 246 to thus couple the inertia of the liquid column 238 to the power vapor diaphragm 244, a flexible diaphragm 248 coupled to the other end of the liquid column 238 by the hydraulic coupling 249 and forming a boundary between the hydraulic coupling 249 and a refrigerant compartment 250 which includes a subcompartment 251 which functions as an energy storing gas cushion space, the power vapor compartment 242 being so disposed in cooperative relationship with the boiler 214 that the gaseous power fluid delivered from the boiler 214 provides energy for oscillating the liquid column 238 forward and return over substantially the same path and with substantially the same inertia in both directions of oscillation; and a first refrigerant vapor compartment 252 connected to receive refrigerant vapor from the low pressure airfinned refrigerant evaporator 222 through an inlet check valve 254 and to expell compressed refrigerant vapor to the air-finned refrigerant condenser 228 through a refrigerant discharge check valve 256. The first refrigerant vapor compartment 252 is separated from the power vapor compartment 242 by a flexible common boundary diaphragm 258 so that including times that the diaphragm 258 is in contact with the diaphragm 244 all diaphragms are at times hydraulically coupled to the liquid column 238 so that upon oscillation of the liquid column 238 energy is transmitted from the liquid column 238 to the refrigerant vapor within the first refrigerant vapor compartment 252 and to the refrigerant vapor within the second refrigerant compartment 250 and its subcompartment 251 so as to substantially adiabatically compress refrigerant vapor and to expell such compressed refrigerant vapor to the refrigerant condenser 228. As shown, the second refrigerant vapor compartment 250, which is disposed at the other end of the liquid column 238, receives refrigerant vapor from the higher pressure refrigerant evaporator 224 through an inlet check valve 262 and discharges compressed refrigerant vapor to the refrigerant condenser 228 through a discharge check valve 264, leaving a residue portion of compressed refrigerant vapor in the subcompartment 251. Refrigerant vapor that is compressed within the

refrigerant compartments

250 and 252 is heated by compression so it can transfer heat to liquid fluid while passing through the heat exchanger 221 on the way to the refrigerant condenser 228.

Sequencing valve means 270 is provided for controlling the mode of operation of the diaphragm pump means 234 by permitting a flow of gaseous power fluid from the boiler 214 to the power vapor compartment 242 during a limited time period when the inertia of the liquid column 238 is offering sufficient pressure opposition to the gaseous power fluid flowing into the compartment 242 that at another time phase of operation substantially adiabatic expansion of the gaseous power fluid takes place within the power vapor compartment 242 and yields work sufficient to further increase the velocity and therefore the kinetic energy of the liquid column 238 so as to substantially adiabatically compress refrigerant vapor within the refrigerant vapor compartments 250, 251 and 252 and to expell compressed refrigerant vapor to the refrigerant condenser 228, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from the power vapor compartment 242 to the power fluid condenser 216 for condensing the expanded power fluid. The sequencing valve means 270 includes a power vapor inlet valve 272, a power vapor exhaust valve 274 and a connecting conduit means 276.

A simple over-pressure protection means 278 is provided as illustrated which is connected to the

hydraulic couplings

246 and 249 by

respective conduits

279 and 281 which are closed to fluid flow by a common springloaded valve member 283 so that liquid can flow in either direction at only those times when there is a predetermined difference in pressure within the

conduits

279 and 281 as caused by a liquid hammer effect at either end of the liquid column 238. In practice, the energy recovering over-pressure protection means 80 of FIG. 1 could be substituted for the over-pressure protection means 278 and it would function in a similar manner to that described relative to FIG. 1.

It is to be noted that the refrigerant vapor compartments 250 and 252 can have a higher total volumetric displacement than the power vapor compartment 242 to thus permit the use of a minimum amount of power vapor required to supply the required amount of energy for compressing refrigerant vapor to thereby increase the efficiency of the heat transfer system 210.

The operation of the heat transfer system 210 of FlGS. 3a through 3d will now be described. Each complete cycle of operation of the heat transfer system 210 is best described if divided into four time phases. The schematic diagrams of each of the FIGS. 3a through 3d illustrate respectively the positioning of the valve components and the direction of fluid flow for the particular time phase of operation being illustrated. Arrows also indicate the direction of motion of the several flexible diaphragms.

Referring to FIG. 3a illustrating the first of the four time phases of operation, at the beginning of this first time phase of operation the

diaphragms

244 and 258 are positioned in their uppermost position within the diaphragm pump means 234 so the spaces of the

compartments

242 and 252 are minimum and the flexible diaphragm 248 is positioned in its lowest position within the diaphragm pump means 234. As shown, the

check valves

254, 256, 262 and 264 are closed, also the power vapor exhaust valve 274 is closed, but the power vapor inlet valve 272 is open, allowing power vapor under pressure to enter the power vapor compartment 242 and act against the diaphragm 244 to accelerate the liquid column 238 in the forward phase of its oscillation which in turn begins to substantially adiabatically compress refrigerant vapor within the refrigerant vapor compartment 250 and the subcompartment 251. FIG. 1a shows the positions of

diaphragms

244 and 248 after considerable movement during th first time phase of operation. During this time phase of operation and before the liquid column 238 has acquired its maximum velocity the inertia of the liquid column 238 offers sufficient opposition to the pressure of the vaporized power fluid flowing into the power vapor compartment 242 that the vaporized power fluid within the 'power vapor compartment 242 retains a large amount of potential energy by virtue of its pressure and volume that during the next time phase of operation substantially adiabatic expansion of the vaporized power. fluid which entered the power vapor compartment 242 during the first time phase of operation will yield work sufficient to further increase the velocity and therefore the kinetic energy of the liquid column 238 so that substantially adiabatic compression of the refrigerant vapor within the refrigerant vapor compartments 250 and 251 can take place and refrigerant vapor can be displaced from the refrigerant vapor compartment 250 during the second time phase of operation.

Referring to FIG. 3b there is illustrated the positioning of the valves and direction of flow of fluids for the heat transfer system 210 for the second time phase of operation, during which time phase of operation both

power vapor valves

272 and 274 are closed. The refrigerant

vapor check valves

254, 256 and 262 are closed, but the refrigerant vapor discharge check valve 264 is open as illustrated after the refrigerant vapor within the refrigerant vapor compartments 250 and 251 has been compressed sufficiently that the pressure within the refrigerant vapor compartments 250 and 251 exceeds the vapor pressure within the air-finned refrigerant condenser 228, at which point in this second time phase the discharge check valve 264 is pushed open and compressed and thereby heated refrigerant vapor is expelled through the discharge check valve 264 and through the conduit means 230 through the heat exchanger 221 to transfer heat to preheat liquid power fluid, and then into the refrigerant condenser 228 where the refrigerant vapor is condensed to a liquid. Liquid refrigerant is allowed to flow at a controlled rate through the controlled conduit 232 to the higher pressure refrigerant evaporator 224.

The second time phase ends when the diaphragm 248 reaches the top boundary of the diaphragm pump means 234. Any residue kinetic energy that the liquid column 238 has left at this time is converted to pressure energy in the hydraulic coupling 249 and is dissipated by forcing liquid through the spring loaded valve member 283 of the over-pressure protection means 278.

Referring to FIG. 30 there is illustrated the positioning of the various valve components and the direction of fluid flow for the heat transfer system 210 for the third time phase of operation, during which time phase the power vapor exhaust valve 274 is open and the power vapor inlet valve 272 is closed, the refrigerant

vapor check valves

256, 262 and 264 are closed, but the refrigerant vapor inlet check valve 254 is open and the liquid column 238 is at the pause transition between forward oscillation and return oscillation. At the beginning of this third time phase of operation the

diaphragms

248 and 258 are positioned at their uppermost positions and the diaphragm 244 at its lowest position, but the illustration in FIG. 3c shows the diaphragm 258 after considerable downward movement. The open power vapor exhaust valve 274 allows expanded power vapor to flow out from the power vapor compartment 242 to the air-finned power fluid condenser 216 where it is condensed to a liquid and the liquid power fluid is pumped back to the boiler 214 by means of the pump 218 and associated conduit220. As expanded power vapor flows out to the power fluid condenser 216 from the power vapor compartment 242 the pressure, as determined by the power fluid condenser 216, drops within the compartment 242 so that the upward pressure on the common boundary diaphragm 258 is reduced to the extent that refrigerant vapor from the low pressure refrigerant evaporator 222 pushes through the inlet check valve 254 into the first refrigerant vapor compartment 252 and depresses the common boundary diaphragm 258 to expell the expanded power vapor from the power vapor compartment 242 until the diaphragm 258 comes to rest against the diaphragm 244.

Referring to FIG. 3d there is illustrated the positioning of the various valve components and the direction of fluid flow for the heat transfer system 210 for the fourth time phase of operation. During the fourth time phase of operation of the system 210 both

power vapor valves

272 and 274 and the

refrigerant check valves

254 and 264 are closed; but the refrigerant vapor discharge valve 256 and inlet check valve 262 which are closed at the beingging of the fourth time phase open as shown in FIG. 3d later in the fourth time phase as will be explained hereinafter. During this fourth time phase of operation the diaphragm 258 rests against the diaphragm 244.

The compressed refrigerant vapor residue in the refrigerant vapor subcompartment 251 expands substantially adiabatically and accelerates the liquid column 138 in the return phase of its oscillation and restores to the liquid column 238 that portion of energy that was stored in the compressed refrigerant vapor residue. The necessary amount of energy left to be restored to the liquid column 238 can be provided for by choosing the size of the subcompartment 251. The refrigerant vapor in the subcompartment 251 and then in the compartment 250 expands substantially adiabatically until its pressure drops below the pressure of the vapor within the higher pressure refrigerant evaporator 224, at which time refrigerant vapor from the higher pressure refrigerant evaporator 224 pushes through the inlet check valve 262 and is replaced in the higher pressure refrigerant evaporator 224 by conversion of some refrierant liquid to vapor, thus precooling remaining refrigerant liquid which is allowed to flow at a controlled rate to the low pressure refrigerant evaporator 222 through the controlled conduit 233. The returning liquid column 238 communicates pressure on the diaphragm 258 through the diaphragm 244 against which it is resting and substantially adiabatically compresses the refrigerant vapor within the refrigerant vapor compartment 252 until the pressure rises above the pressure of vapor within the refrigerant condenser 228, at which time the refrigerant discharge check valve 256 is pushed open as illustrated in FIG. 3d and compressed and thereby heated refrigerant vapor is delivered through the conduit 230 and the heat exchanger 221 to the refrigerant condenser 228 where it is condensed to a liquid. The fourth time phase of the cycle is completed when the

diaphragms

244 and 258 reach the limiting upper position in the diaphragm pump means 234 and any residual energy of the liquid column 238 is dissipated through the over-pressure protection means 278 as explained in the first time phase of operation.

Referring to FIGS. 40 through 4d there are shown four time phases of operation of one complete cycle of operation of a thermally powered heat transfer system 310 illustrating another embodiment of the teachings of this invention in which like components of FIGS. 4 and 2 have been given the same reference characters and in which heat transfer system a refrigerant and power fluid with a rather large difference between their boiling points can be effectively utilized, thus permitting heat to be supplied to boil the power fluid at a higher temperature which in turn increases the thennal efficiency of the system. For instance, dichlorodifluoromethane (R-12) can be used as a refrigerant, and a fluid such as trichloromonofluoromethane (R-ll) or trifluorotrichloroethane (R-ll3) can be used as the power fluid.

The heat transfer system 310 as shown in FIGS. 4a through 4d has means for supplying power fluid in a gaseous state under adequate pressure and includes the following components: a heat source 312 which supplies heat to a boiler 314, an air-finned power fluid condenser 316 for condensing expanded and returned power vapor, a pump 318 and conduit 320 for returning condensed liquid power fluid to the boiler 314, and a heat exchanger 321 for preheating liquid power fluid before it is returned to the boiler 314. Of course, the power fluid condenser 316 may be omitted if steam is used as the gaseous power fluid, in addition the heat source 312 and the power fluid condenser 316 may be omitted if a tank or other source (not shown) of compressed air is substituted for the boiler 314. Means for condensing and for reevaporating refrigerant fluid includes an air-finned refrigerant evaporator 322 with associated liquid precooler 324 and connecting conduit 326, an air-finned refrigerant condenser 328 with associated connecting conduit 330, and a controlled conduit means 332 providing a means for returning comdensed liquid refrigerant from the refrigerant condenser 328 to the liquid precooler 324 where it is precooled before flowing into the refrigerant evaporator 322.

In order to pump refrigerant vapor from the refrigerant evaporator 322 and return compressed refrigerant vapor to the refrigerant condenser 328, a diaphragm pump means 334 is provided which receives its energy for pumping from the gaseous power fluid supplied by the boiler 314.

The diaphragm pump means 334 includes a conduit 336 enclosing a liquid column 338; pneumatic driving means 340 including a power vapor compartment 342 associated with one end of the liquid column 338 through a flexible diaphragm 344 which is hydraulically coupled to the liquid column 338 by means of a hydraulic coupling 346 to thus couple the inertia of the liquid column 338 to the power vapor diaphragm 344 so that the liquid column 338 in effect provides inertia for the power vapor diaphragm 344 and so that expansion of gaseous power fluid within the power vapor compartment 342 provides energy for oscillating the liquid column 338 forward and return over substantially the same path and with substantially the same inertia in both directions of oscillation; and a dual purpose refrigerant vapor compartment flexible diaphragm 348 hydraulically coupled to the inertia of the liquid column 338 at the other end of the liquid column 338 by a hydraulic coupling 349 and forming a boundary between a refrigerant vapor compartment 350, which includes a subcompartment 351, and the hydraulic coupling 349, which compartment 350 is so disposed in cooperative relationship with the air-finned refrigerant evaporator 322 so as to receive refrigerant vapor from the evaporator 322 through an inlet check valve 354 and to compress the received refrigerant vapor upon oscillation of the liquid column 338 by receiving energy from the liquid column 338 and to discharge compressed refrigerant vapor through a discharge check valve 356 back to the air-finned refrigerant condenser 328 to be condensed to a liquid.

A ring valve seat 360 surrounding the opening to the inlet check valve 354 and discharge check valve 356 is provided to isolate the subcompartment 351 when the

Claims

1. A heat transfer system using as working substances a power fluid and a refrigerant fluid and comprising the following connected components to form the heat transfer system: means for supplying the power fluid in a gaseous state and under pressure; means for condensing and for reevaporating the refrigerant fluid; diaphragm pump means including conduit means enclosing a liquid column, pneumatic driving means including power vapor compartment means, said pneumatic driving means being so disposed in cooperative relationship with the liquid column and with said means for supplying the power fluid in a gaseous state that such gaseous power fluid provides energy for oscillating the liquid column over substantially the same pAth and the liquid column maintains substantially the same inertia in both directions of said oscillation, and refrigerant vapor compartment means so disposed in cooperative relationship with the liquid column and with said means for condensing and reevaporating the refrigerant fluid that said refrigerant vapor compartment means receives refrigerant vapor from said means for condensing and for reevaporating the refrigerant fluid, and energy is transmitted from the liquid column to the refrigerant vapor received in said refrigerant vapor compartment means to compress the refrigerant vapor within the said refrigerant vapor compartment means and expell compressed refrigerant vapor to said means for condensing and for reevaporating the refrigerant fluid; and means including sequencing valve means for controlling the mode of operation of said diaphragm pump means by permitting a flow of gaseous power fluid from said means for supplying the power fluid in a gaseous state to said power vapor compartment means during a time phase of operation when the inertia of said liquid column is offering sufficient pressure opposition to the gaseous power fluid flowing into said power vapor compartment means that at another time phase of operation, as determined by said sequencing valve means, substantially adiabatic expansion of such gaseous power fluid in said power vapor compartment means will yield work sufficient to compress refrigerant vapor in said refrigerant vapor compartment means, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from said power vapor compartment means.

2. The heat transfer system of claim 1 in which at least the refrigerant fluid is a fluorocarbon.

3. The heat transfer system of claim 1 in which said power vapor compartment means and said refrigerant compartment means are disposed on the same end of said enclosed liquid column.

4. The heat transfer system of claim 1 in which a portion of said refrigerant vapor compartment means is disposed on each end of said enclosed liquid column.

5. The heat transfer system of claim 1 in which a portion of said power vapor compartment means is disposed on each end of said enclosed liquid column.

6. The heat transfer system of claim 1 in which a portion of said refrigerant vapor compartment means is disposed on each end of said enclosed liquid column and in which said means for condensing and for reevaporating the refrigerant fluid has two temperature and pressure stages of reevaporator, one stage of which is connected to the portion of said refrigerant vapor compartment means on one end of said enclosed liquid column and the other stage of which is connected to the portion of said refrigerant vapor compartment means on the other end of said enclosed liquid column.

7. The heat transfer system of claim 1 in which said power vapor compartment means is disposed on one end of said enclosed liquid column and said refrigerant vapor compartment means is disposed on the other end of said enclosed liquid column.

8. The heat transfer system of claim 1 in which a portion of said power vapor compartment means and a portion of said refrigerant vapor compartment means is disposed on each end of said enclosed liquid column.

9. A heat transfer system using as working substances a power fluid and a refrigerant fluid and comprising the following connected components to form the heat transfer system: means for supplying the power fluid in a gaseous state and under pressure; means for condensing and for reevaporating the refrigerant fluid; diaphragm pump means including conduit means enclosing a liquid column, pneumatic driving means including power vapor compartment means having a diaphragm hydraulically coupled to the liquid column so that the liquid column in effect provides inertia for said diaphragm and said power vapor compartment means being so disposed in cooperative relationship with said means for supplying the power fluid in a gaseous state that the gaseous power fluid prOvides energy for oscillating the liquid column over substantially the same path and the liquid column maintains substantially the same inertia in both directions of said oscillation; and refrigerant vapor compartment means so disposed in cooperative relationship with the liquid column and with said means for condensing and reevaporating the refrigerant fluid that said refrigerant vapor compartment means receives refrigerant vapor from said means for condensing and for reevaporating refrigerant fluid, and energy is transmitted from the liquid column to the refrigerant vapor received in said refrigerant vapor compartment means to compress refrigerant vapor within said refrigerant vapor compartment means and expell compressed refrigerant vapor to said means for condensing and for reevaporating the refrigerant fluid; and means including sequencing valve means for controlling the mode of operation of said diaphragm pump means by permitting a flow of gaseous power fluid from said means for supplying the power fluid in a gaseous state to said power vapor compartment means during a time phase of operation when the inertia of said liquid column is offering sufficient pressure opposition to the gaseous power fluid flowing into said power vapor compartment means that at another time phase of operation, as determined by said sequencing valve means, substantially adiabatic expansion of such gaseous power fluid in said power vapor compartment means will yield work sufficient to compress refrigerant vapor in said refrigerant vapor compartment means, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from said power vapor compartment means.

10. The heat transfer system of claim 9 in which over-pressure protection means is provided for said diaphragm pump means, said over-pressure protection means including a pressurized gas filled compartment and a liquid receiving compartment, said pressurized gas filled compartment and said liquid receiving compartment being separated by a movable partition and said liquid receiving compartment being disposed to receive liquid from said hydraulic coupling disposed between said diaphragm and the liquid column at those times when the hydraulic pressure in said hydraulic coupling exceeds the pressure within said pressurized gas filled compartment and being disposed to expell the received liquid from said liquid receiving compartment to said hydraulic coupling during the time phase of operation when gaseous power fluid is permitted to flow from said means for supplying the power fluid in a gaseous state to said power vapor compartment means.

11. The heat transfer system of claim 9 in which said power vapor compartment means is disposed at only one end of the liquid column and in which said pneumatic driving means also includes means defining an energy storing gas cushion disposed in cooperative relationship with that end of the liquid column opposite from the end of the liquid column that said power vapor compartment means is disposed.

12. A heat transfer system using as working substances a power fluid and a refrigerant fluid and comprising the following connected components to form the heat transfer system: means for supplying the power fluid in a gaseous state and under pressure; means for condensing and for reevaporating the refrigerant fluid; diaphragm pump means including conduit means enclosing a liquid column, pneumatic driving means including a power vapor compartment having a power vapor diaphragm hydraulically coupled to the liquid column so that the liquid column in effect provides inertia for said power vapor diaphragm, and said power vapor compartment being so disposed in cooperative relationship with said means for supplying a power fluid in a gaseous state that the gaseous power fluid provides energy for oscillating the liquid column over substantially the same path and with substantially the same inertia in both directions of said oscillation, and refrigerant vapor compartment means includIng a compartment having a boundary diaphragm in common with said power vapor compartment, said refrigerant vapor compartment means being disposed in cooperative relationship with said means for condensing and for reevaporating the refrigerant fluid so as to receive refrigerant vapor from said means for condensing and for reevaporating the refrigerant fluid and so that upon oscillation of the liquid column energy is transmitted from the liquid column to refrigerant vapor received in said refrigerant vapor compartment means to compress refrigerant vapor within said refrigerant vapor compartment means and expell compressed refrigerant vapor to said means for condensing and for reevaporating the refrigerant fluid; and means including sequencing valve means for controlling the mode of operation of said diaphragm pump means by permitting a flow of gaseous power fluid from said means for supplying the power fluid in a gaseous state to said power vapor compartment during a time phase of operation when the inertia of the liquid column is offering sufficient pressure opposition to the gaseous power fluid flowing into said power vapor compartment that at another time phase of operation, as determined by said sequencing valve means, substantially adiabatic expansion of such gaseous power fluid in said power vapor compartment will yield work sufficient to compress refrigerant vapor in said refrigerant vapor compartment means, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from said power vapor compartment.

13. A heat transfer system using as working substances a power fluid and a refrigerant fluid and comprising the following connected components to form the heat transfer system: means for supplying the power fluid in a gaseous state and under pressure; means for condensing and for reevaporating the refrigerant fluid; diaphragm pump means including conduit means enclosing a liquid column, a separate power vapor compartment associated with each end of the liquid column through a power vapor diaphragm which is hydraulically coupled to its respective end of the liquid column to couple the inertia of the liquid column to the respective power vapor diaphragm and each said separate power vapor compartment being so disposed in cooperative relationship with said means for supplying a power fluid in a gaseous state that the gaseous power fluid provides energy for oscillating the liquid column over substantially the same path and with substantially the same inertia in both directions of said oscillation, and a separate refrigerant vapor compartment associated with each end of the liquid column and having a boundary in common with the respective separate power vapor compartment associated with its respective end of the liquid column, and each of the separate refrigerant vapor compartments being disposed in cooperative relationship with said means for condensing and for reevaporating the refrigerant fluid so as to receive refrigerant vapor from said means for condensing and for reevaporating the refrigerant fluid and so that upon oscillation of the liquid column energy is transmitted from the liquid column to compress the refrigerant vapor received in the respective separate refrigerant vapor compartment toward which the liquid column is moving and to expell compressed refrigerant vapor to said means for condensing and for reevaporating the refrigerant fluid; and means including sequencing valve means for controlling the mode of operation of said diaphragm pump means with respect to each end of the liquid column by permitting a flow of gaseous power fluid from said means for supplying the power fluid in a gaseous state to each of the separate power vapor compartments during a time phase of operation for each separate power vapor compartment when the inertia of the liquid column is offering sufficient pressure opposition to the gaseous power fluid flowing into the particular respective separate power vapor compartment that at another time phase of oPeration for each separate power vapor compartment substantially adiabatic expansion of such gaseous power fluid can take place and will yield work sufficient to compress refrigerant vapor in the separate refrigerant vapor compartment associated with the opposite end of the liquid column, and by permitting during still a different time phase of operation for each of the separate power vapor compartments a flow of expanded gaseous power fluid from each of the respective separate power vapor compartments.

14. A heat transfer system using as working substances a power fluid and a refrigerant fluid and comprising the following connected components to form the heat transfer system: means for supplying the power fluid in a gaseous state and under pressure; means for condensing and for reevaporating the refrigerant fluid; diaphragm pump means including conduit means enclosing a liquid column, a power vapor compartment having a power vapor diaphragm hydraulically coupled to one end of the liquid column so that the liquid column in effect provides inertia for said power vapor diaphragm, and said power vapor compartment being so disposed in cooperative relationship with said means for supplying a power fluid in a gaseous state that the gaseous power fluid provides energy for oscillating the liquid column over substantially the same path and with substantially the same inertia in both directions of said oscillation, a first refrigerant vapor compartment connected to receive refrigerant vapor from said means for condensing and for reevaporating the refrigerant fluid and having a boundary diaphragm in common with said power vapor compartment, and a second refrigerant vapor compartment having a refrigerant vapor diaphragm hydraulically coupled to the other end of the liquid column and containing refrigerant vapor a residue portion of which functions in operation as a pneumatic cushion to effect a reversal of oscillation of the liquid column back toward said power vapor compartment, said first refrigerant vapor compartment and said second refrigerant vapor compartment being disposed in cooperative relationship with said means for condensing and for reevaporating the refrigerant fluid so that upon oscillation of the liquid column energy is transmitted from the liquid column to refrigerant vapor within said first and within said second refrigerant vapor compartment so as to compress refrigerant vapor within said first and said second refrigerant vapor compartment and to expell compressed refrigerant vapor from said first and said second refrigerant vapor compartment to said means for condensing and for reevaporating the refrigerant fluid; and means including sequencing valve means for controlling the mode of operation of said diaphragm pump means by permitting a flow of gaseous power fluid from said means for supplying the power fluid in a gaseous state to said power vapor compartment during a time phase of operation when the inertia of the liquid column is offering sufficient pressure opposition to the gaseous power fluid flowing into said power vapor compartment that at another time phase of operation, as determined by said sequencing valve means, substantially adiabatic expansion of such gaseous power fluid in said power vapor compartment will yield work sufficient to compress refrigerant vapor in said first and said second refrigerant vapor compartment, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from said power vapor compartment.

15. The heat transfer system of claim 14 in which over-pressure protection means is provided for said diaphragm pump means, said over-pressure protection means including a pressurized gas filled compartment and a liquid receiving compartment, said pressurized gas filled compartment and said liquid receiving compartment being separated by a movable partition and said liquid receiving compartment being disposed to receive liquid from said hydraulic coupling disposed between said power vapor diaphragm and the liquiD column at those times when the hydraulic pressure in said hydraulic coupling disposed between said power vapor diaphragm and the liquid column exceeds the pressure within said pressurized gas filled compartment and being disposed to expell the received liquid from said liquid receiving compartment to said hydraulic coupling disposed between said power vapor diaphragm and the liquid column during the time phase of operation when gaseous power fluid is flowing from said means for supplying the power fluid in a gaseous state to said power vapor compartment.

16. The heat transfer system of claim 14 in which said means for condensing and for reevaporating the refrigerant fluid includes two separate reevaporators one of which is interconnected with said first refrigerant vapor compartment and the other of which is interconnected with said second refrigerant vapor compartment.

17. A heat transfer system using as working substances a power fluid and a refrigerant fluid and comprising the following connected components to form the heat transfer system: means for supplying power fluid in a gaseous state and under pressure; means for condensing and for reevaporating the refrigerant fluid; diaphragm pump means including conduit means enclosing a liquid column, a power vapor compartment having a power vapor diaphragm hydraulically coupled to one end of the liquid column so that the liquid column in effect provides inertia for said power vapor diaphragm, and said power vapor compartment being so disposed in cooperative relationship with said means for supplying a power fluid in a gaseous state that such gaseous power fluid provides energy for oscillating the liquid column over substantially the same path and with substantially the same inertia in both directions of said oscillation, and a refrigerant vapor compartment having a refrigerant vapor diaphragm hydraulically coupled to the other end of the liquid column and being disposed in cooperative relationship with said means for condensing and for reevaporating the refrigerant fluid so as to receive refrigerant vapor from said means for condensing and reevaporating refrigerant fluid so that upon oscillation of the liquid column energy is transmitted from the liquid column to refrigerant vapor within said refrigerant vapor compartment to compress refrigerant vapor within said refrigerant vapor compartment and expell compressed refrigerant vapor from said refrigerant vapor compartment to said means for condensing and for reevaporating refrigerant fluid, leaving a residue portion of the refrigerant vapor within said refrigerant vapor compartment to function as a pneumatic cushion to effect a reversal of oscillation of the liquid column back toward said power vapor compartment; and means including sequencing valve means for controlling the mode of operation of said diaphragm pump means by permitting a flow of gaseous power fluid from said means for supplying the power fluid in a gaseous state to said power vapor compartment during a time phase of operation when the inertia of the liquid column is offering sufficient pressure opposition to the gaseous power fluid flowing into said power vapor compartment that at another time phase of operation, as determined by said sequencing valve means, substantially adiabatical expansion of such gaseous power fluid in said power vapor compartment will yield work sufficient to compress refrigerant vapor in said refrigerant vapor compartment, and by permitting during still another time phase of operation a flow of expanded gaseous power fluid from said power vapor compartment.