US1966896A - Pump - Google Patents

Description

July 17, 1934.

H. E. LA BoUR PUMP Filed May 29, 1929 3 Sheets-Sheet 1 /////AA W July 17, 1934.

H. E. LA BoUR 1,966,896

PUMP

Filed May 29, 1929 3 Sheets-Sheet 2 4e 4 713 Il 4 47 4; ///////////ml// @QQ 5 .2

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July 17, 1934.

H. E. LA BouR 1,966,896

PUMP l Filed May 29, 1929 3 Sheets-Sheet 5 70 |Ef 68 in ll 64 l 67 @Wye/2% ,graz/Ela Boar Patented July 17, 1934 UNITED STATES PATENT OFFICE 10 Claims.

My invention relates to pumps more particularly of the self-priming type rst disclosed in my prior Patent No. 1,578,236, granted March 23, 1926, and constitutes more specifically an improvement upon the type of pump disclosed in my copending application, Serial No. 251,489, hled February 3, 1928.

In the manufacture of pumps of the self-priming type more particularly characterized by the employment of a return passage way from the separating chamber into the peripheral part of the impeller, and in which such return passage way serves upon priming of the pump as an additional discharge passage way, I have found that the arrangements shown in said previous patent and in the copending application, while perfectly satisfactory from the hydraulic and operating standpoints, are structurally bulky and involve difficulties in mounting.

In the larger sizes of pumps the over all height becomes objectionable and for contractors purposes the form of pump heretofore employed is inconvenient.

I have conceived, therefore, the necessity of developing a more compact type of pump which will have the required operating characteristics and which, however, can be disposed in less space and in more compact form.

I have conceived, therefore, the possibility of disposing the separating chamber about the pump casing, either in the same plane or in a parallel plane, to provide a more compact and stronger construction.

To secure satisfactory separation of air and water discharged from the primary discharge throat and passageway of the pump, I have arranged to direct the stream so discharged in a concave path with the concave side towards the pump runner and nearer to the outlet of the separating chamber than the convex side, thereby permitting more rapid separation of air and water than has heretofore been possible and not requiring the dense outer portion of the discharge stream to cross the less dense inner or concave portion of the stream. Better and more rapid separation occurs within limited space than has heretofore been possible in pumps of this general type.

The secondary discharge passageway which also functions as a return passageway during the priming stage is disposed adjacent the discharge throat and passageway, and leads to a point in the separating chamber from which liquid may readily be received during the priming phase. That is to say, the separating chamber now has its lowest point below the reentry point of liquid into the runner or impeller.

Also the main discharge throat is preferably disposed above the bottom of the separating chamber, and in the form of invention herein specifically shown, said discharge throat and passageway leads from the lower half of the impeller or runner. 'Ihe position of the main discharge throat and passageway and the secondary discharge throat and passageway may obviously be varied within my invention, as may also the position of the outlet from the ber.

Preferably a new arrangement of the travel of liquid discharged from the impeller is employed herein. A new method of operation is involved, and numerous features of detailed novelty are disclosed in the present application, all of which will be more apparent from the following detailed description and the appended claims.

The novel method of operation which is herein involved will be more apparent from the detailed description. Sufiice it to say here that the stream of air carrying liquid is discharged in a path of single curvature, in the preferred form, so that the air which is carried by the stream is preferably permitted to escape as soon as the discharge throat is cleared.

While the discharge stream may be led out of the plane of the runner within my invention the concave side of the stream in the case of the curved path will contain the maximum amount of air and this is freely separable as soon as the throat is passed, the air being permitted to disrharge laterally from the concave side of the stream, the dense liquid part of the stream being on the convex side and being led past the point of lateral discharge of air.

Even if thestream should be discharged out of the plane of the runner or impeller, and this may be the case where the separating chamber is offset with respect to the pump casing, the dense part of the discharge stream is not caused to cross or intersect the less dense part of the stream in which the maximum percentage of air is carried.

Now in order to acquaint those skilled in the art with the manner of constructing and operating a device embodying my invention, I shall describe in connection with the accompanying drawings a specific embodiment of the invention.

In the drawings:

Figure 1 is a vertical longitudinal section through the pump and separating chamber with separating chamother parts connected thereto shown partly in section and partly in elevation;

Figure 2 is a cross sectional View taken on the line 2-2 of Figure 1, and looking in the direction of the arrows;

Figure 3 is a fragmentary cross section taken on the line 3-3 of Figure 2;

Figure 4 is a similar cross section taken on the line 4-4 in Figure 2;

Figure 5 is a side elevational view of a form of pump showing the intake trap and the discharge disposed on the opposite side;

Figure 6 is a diagram of the travel of the discharged stream of liquid and air, and the return of liquid to the impeller, and the freeing of air; and

Figures 7 and 8 are diagrams illustrating different theories of the mode of operation of this pump.

Referring now to Figure 1, the impeller 1 is disposed in a casing 2 having a cover plate 3, said cover plate 3 providing an inlet opening 4 which preferably communicates with an inlet trap 5, the inlet trap 5 having a connecting ange 6 and the plate 3 having a cooperating flange 7, these flanges being bolted together. Between the flange 7 and the body of the plate 3, I provide a frusto-conical portion 8 which allows the incoming liquid to be distributed completely around the periphery of the impeller or runner 1, said impeller or runner 1 havin,s a ring member 9 provided with radially extending fins or blades forming between them buckets for carrying fluid. The fins or blades 10 are substantially flush with the inner periphery of the ring 9, but the outer ends of these fins or blades extend beyond the outer periphery of the ring 9 and are disposed on opposite sides of the same. The result is that the buckets defined between the blades and the channel 1l in which these buckets run are U-shaped with the concave side of the U facing inwardly towards the axis of the shaft 12.

It is within the invention to modify the form of the fins or blades so as to vary the form of the bucket, but I have found the form herein shown to be satisfactory and to give excellent results.

The ring 10 is carried on a spider comprising the central hub 13 and radial arms 14, which radial arms are preferably in alignment with certain ones of the fins or blades 10-10. The arms 14 are somewhat reduced in width where they join the fins or blades 10 and liquid can freely pass into both sides of the bucket. The shape of the ring 9 may be varied within the invention and the length of the fins 10 may likewise be varied, but the specific form shown herein is preferable. The forward portion of the hub 13 is preferably given a smooth configuration to avoid eddy currents and to permit the liquid from the tapered inlet connection 8 to be distributed into the channel 11 throughout the entire periphery. The cover plate 3 has a flange 15 which is bolted against a face 16 as by means of the bolts 17, and it has a tapered conical shoulder 19 fitting against a companion shoulder 20 formed as an integral part of the casing and extending off from the bottom of the channel 11. This channel 11 is defined between the flat part 21 of the cover plate 3 and the rear part of the casing and radially is defined by a cylindrical surface formed in the casing 2. All the bolts 17 are shown as extending through the solid part of the casing immediately outside of the channel 11, but it is to be understood that these bolts may be replaced by studs or cap screws or any other suitable method of fastening a cover plate 3 upon the back plate or main part 2 of the casing. The back plate 2 is provided with a boss 23 which is adapted to be mounted in a suitable split clamp 24 formed at the upper end of a supporting bracket 25.

The supporting bracket 25 is provided with a base 26, which rests upon a suitable base plate 27. A fibrous or other packing 29 is disposed about the shaft 12 in a recess formed in the hub 23 and the same is held in place by a gland follower 30, which gland follower 30 may have a packing 31 disposed in a recess in the outer end of the same. The packing 31 is engaged by a follower 32. Obviously any suitable form of packing may be employed for sealing off the shaft from the casing or vice versa. The bracket 25 supports the bottom part of the pump above the base 27 and an angular bracket 33 is disposed between the end of the base and the bottom of trap and strainer 5 to give structural support to said end of the pump and to the trap and strainer.

The separator chamber 35 is disposed about the pump casing, in this case the separator chamber 35 is shown as lying in the same plane as the pump casing. This chamber is formed of a cylindrical drum shape extension of the pump casing preferably being cast integral with the pump casing and having passages and a throat cored therein.

Obviously the construction may be changed by splitting the casing and the chamber, either on the same plane or on different sections to facilitate the construction and assembly of the device. The chamber 35 is formed of an outer cylindrical wall 36, the center of which cylindrical wall is offset with respect to the axis of the pump shaft 12, so that the chamber and the pump casing are eccentric but disposed in the same plane in this case. Obviously any other different configuration of the chamber might be employed without departing from the invention.

The chamber 35 has the side walls 37 and 38 which are ared in as indicated at 39 and 40 respectively to join the narrower pump casing. The wall 38, as shown in Figure 1, is provided with an outlet opening 41 which leads into a discharge connection 42, having the bolting flange 43. It will be observed that the lateral opening 4l, which forms the outlet for the separated air during the priming stage and which forms the discharge passageway from the chamber upon operation of the pump on liquid is disposed radially inwardly from the outer wall 36 by a short section of wall 44 for the purpose as will be explained later of permitting liquid to be directed around the inner periphery of the wall 36, while air passes off laterally into the outlet 42.

The plugs 46 in the outer periphery of the casing are so placed to close openings through which the cores are supported in casting the casing and chamber.

It will be observed that a considerable portion of solid metal surrounds the channel l1, between the pump and the chamber, and through this the bolt 17 may be passed, and through this solid metal the discharge throat and passageway 48 are formed. This discharge throat 47 extends off substantially tangential from the lower half of the impeller. The discharge throat has a central constricted portion and then opens out into a wider discharge passageway, which is directed in a curved path upwardly along the cylindrical wall 36 in a counter clockwise direction, as viewed in Figure 2. The discharge from this main throat and passageway is thereby directed in a curved path the concave side of which lies at all times towards the impeller l, at least until the discharge stream has passed the outlet passageway 41 so that air may readily be released from the inner concave side of the stream.

A secondary discharge throat 49 and passageway leads from a point just posterior in the direction of travel of the impeller from the main throat and passageway. The secondary discharge throat 49 is smaller than the primary discharge throat 47 in the form herein shown. The proportions of these two throats and discharge passageways may be varied within limits in accordance with my invention. The passageway 50 is curved around the impeller and leads down to an opening at 51 at substantially the bottom of the chamber 35. In the operation of this pump the passageway 50 forms during the priming stage, that is while air is being delivered from the pump casing into the separator for priming the intake pipe, a reentry passageway for liquid.

The operation of the device is as follows. Assume that liquid is trapped in the pump casing and in the chamber and is prevented from running out the intake connection by the intake trap 5, the impeller 1 is rotated in the counter clockwise direction, as viewed in Figure 2, whereupon the liquid in the pump casing will be driven out through the main discharge throat 47 and perhaps during the irst action of the impeller some is driven out the secondary throat 49, but very quickly the discharge at the main throat 47 reduces the pressure within the casing to a point where liquid will flow into the casing through the passageway 50. Ihe level of liquid trapped in the casing will normally stand even with the bottom of the short wall 44 or at least above the top of the passageway 50 so that by the siphoning action of discharging liquid out the main throat 47 other liquid will be drawn into the passageway 50.

Also liquid is free to enter from the intake trap 5. Such discharge will occur to a point where air tends to enter the impeller 1 from the intake side whereupon the impeller begins to discharge air and liquid out of the main throat 47 into the separator 35.

By reference to the diagram of Figure 6 the course of the liquid and air will be understood. The stream of air and liquid 52 issuing from the main throat 47 is directed upwardly by the disi charge passageway 48 into engagement with the outer cylindrical wall 36 in the general region indicated by reference numeral 53 on Figure 2. Due to the greater specific gravity of the liquid in the stream the liquid tends to be thrown outward along the curved wall 36 and to be directed past the outlet 4l and downwardly along the curved wall 36 to the opening 5l where both because of the suction exerted in the passageway 50 and the head of liquid above the bottom of the passageway 51 liquid reenters the impeller 1 through the passageway 50, all as indicated by the line of longer arrows 54 shown on Figure 6.

The concave side of the discharge stream carries substantially all of the entrained air. The entrained air is readily able to free itself from the liquid as it has a relatively large area from which to disentrain itself and a relatively large volume in which disentrainment can occur. The major part of the air, therefore, separates immediately from the liquid and is free to travel upwardly and laterally out the discharge opening 41 as indicated at reference numeral 55 on Figure 6. The velocity of the Vissuing stream is checked by the increase in section of the stream. That is to say, the stream is free to expand in the large volume of the top of the chamber and hence facilitate separation of the air by this action.

'Ihe short arrows 56 shown on Figure 6 indicate the air disentraining from the stream of liquid, the liquid then entering the return passageway 50 and passing back into the peripheral part of the impeller 1.

A pocket may be formed at the sides of the impeller at the inner end of the return passageway 50, as disclosed in my prior patent, above referred to.

Upon completion of the priming stage, that is, when solid liquid enters the impeller from the intake, the discharge of liquid from the impeller is increased and the ow in passageway 50 is reversed and the throat 49 becomes a discharge throat secondary to the main discharge throat 47.

Thereby not only is the return ilow of liquid prevented while the pump is operating on straight liquid, but increased discharge is secured whereby the efliciency of the pump is made higher than in known types where there is a by pass from the discharge back into the inlet.

The liquid discharged from the passageway 50 enters the separator 35 through the discharge opening 51, and finds its way on either side of the chamber through the outlet opening 41 and then up to the discharge passageway 42. It will be apparent that the width of the chamber 35 is greater than the width of the opening 51, so that liquid may freely pass by said opening 51 on either side and there is a substantially free discharge of liquid from the passageway 50. At the same time the opening 51 is so placed that practically all of the liquid in the separating chamber 35 may be employed in the priming stage.

There are several different actions involved in this form of pump and the exact nature of the entrainment of air in the liquid is hard to determine.

Apparently there is a denite eddy current action created by the vanes or blades 11 in withdrawing from the issuing stream which sets up distinct waves as indicated at 58 in the diagram of Figure 8. In this diagram the adjacent part of the casing, indicated at 59, has been raised to reveal the character of the issuing stream of air and liquid.

These eddy currents or waves 58 which are created by the lateral withdrawal of the buckets of the vanes or ns 10, serve the dual function of actually entraining air by the churning motion of the liquid and, second, the irregularities of the issuing stream of liquid tend to pocket and wipe along air as these waves or irregularities or eddies engage the throat indicated at 60. It will be understood that Figure 8 is merely an explanatory diagram and not an actual construction.

I conceive also thatin the impeller which I employ there is a spilling from one bucket to the next as the rotor moves in the channel. That is to say, due to the inertia of the liquid it tends to pile up against the pushing side of the vane and to spill over the inner edge of the vane into the next following bucket. In so doing a churning of air and liquid together is secured and the issuing stream at the throat 47 may, therefore, be considered as consisting of a denser mixture of liquid and air at the peripheral part and a less dense mixture of air and liquid at the inner or concave side.

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Hence, even if the eddy or wave effect of the withdrawal of the bucket laterally from the issuing stream be disregarded, and we consider only an emulsion of air and liquid as constituting the steam as indicated at 61 in the Figure 7, it will be seen that due to the centrifugal force the tendency is for the liquid to separate out toward the right as Viewed in Figure 7 along the wall 62, and the air to be displaced toward the left along the wall 63 viewed in Figure 7.

I conceive that both of these actions occur in the pump of my invention and I consider that the embodiment of either or both is within the scope of my invention as defined by the appended claims.

Obviously the mechanical construction of the pump may be widely varied.

In Figure 5, I have shown a pump substantially like that shown in Figures 1 to 4 except that the discharge connection 64 is placed on the shaft side so that the intake trap 65 may be brought closer to the wall 41. In this case the intake trap 65 is provided with a bolting flange 66 by which the trap 65 is directly bolted to the pump casing without the employment of a separate cover plate 3.

The trap 65 has an inlet opening 67 provided with a bolting flange and at its top has a removable cover member 68 by which access to a flanged cup shaped screen 69, may be had. A suitable clamping yoke 70 is provided for holding the cover plate 68 on top of the trap member 65. Pins pass through lugs at each side and extend also through the ends of the yoke 70. A central screw passes down through the yoke and clamps down the cover 68. The trap 65 has a frusto conical wall defining an inlet of flaring character. This frusto conical wall extends from the flange 66 to the left inside the trap as viewed in Figure 5.

The flanged cup shaped screen may be inspected through the top opening which is large enough to permit the screen to be removed and replaced. It rests upon inwardly extending means shown as a circular flange below the inlet opening 67.

In the form shown in Figure 1 the disposal of the discharge connection 42 at the outer end away from the shaft l2 prevents any drip from the discharge line from coming on to the shaft or packing gland. Leakage from the packing gland is conducted through the base member 27 by a funnel 7l which fits under an extension 72 of the boss 23 so as to conduct any leakage from the gasket down through the base to a suitable discharge point. This is highly desirable where acid is handled or where any corrosive liquid is handled by the pump.

In the present form of pump the issuing stream of liquid tends inherently to stratify itself without the necessity for further centrifugal separation.

The stream issues in the concave path which is held long enough to let the less dense mixture free its air on the concave side of the path. This avoids any tendency to reentrain the air by bending the stream back and forth in the same plane or out of a plane, as is practiced in the devices of the prior art.

While in the pump which I have shown the separating action described is substantially pure, that is, I get the separation by holding the air on the concave side of the discharge stream and slowing down the stream without remixing and without further disentraining action, it is to be understood that so long as the action which I have described and claimed occurs it is immaterial what further addition thereto may be made without departing from my invention. That is to say,

I contemplate within my invention forms of pumps in which the above action may be combined with other actions. i

This form of pump and separating chamber may be used either in the vertical position shown or it may be placed in horizontal poistion, l. e. with the shaft 12 extending vertically. The outlet 41 should in that event, be placed in the wall which is uppermost and radially the cylindrical wall. I believe that the form of pump and its method of operation are broadly new.

I do not intend to be limited to the specific construction nor to the specific mode of operation above described in detail.

I claim:

1. In a pump, a casing, a runner in the casing, a drum like chamber embracing the casing, a first discharge throat and passageway leading from the casing into the chamber at one side thereof, a second discharge throat and passageway leading from the casing into the lower part of the chamber and an outlet at the upper part of the chamber.

2. In a pump, a casing, a runner in the casing, an inlet for the casing, a chamber encircling and embracing the casing and having its axis substantially parallel to and separate from the axis of the runner, a first discharge throat and passageway leading from the casing into the chamber at one side thereof, a second discharge throat and passageway leading from the casing into another part of the chamber and an outlet for the chamber communicating with the interior of the same within the outer periphery of the chamber.

3. In a pump, a casing, comprising a channel, a runner in the casing having buckets in the channel, said runner lying in substantially a vertical plane, a tangential discharge passageway opening from the lower half of the channel and being directed upwardly, a separating chamber embracing the channel and having its upper wall spaced from the channel further than its lower wall is spaced from the channel, and a lateral outlet from the upper part of the chamber.

4. In a pump, a casing, having a channel, a runner cooperating with the channel, said runner having a series of buckets, a discharge throat and passageway leading from the lower part of the channel and being directed in a curved upward path, a separating chamber of generally drum like shape and embracing said casing with its axis above the axis of the casing, the discharge passageway being adapted to direct the discharge from the runner along the curved wall of the drum and an outlet from the chamber lying radially inwardly from the curved wall.

5. A self priming pump having a casing, a primary discharge passageway, a secondary discharge passageway, a separator communicating with said passageways, said primary discharge passageway directing fluid therefrom upwardly in the separator and the secondary passageway directing fluid therefrom downwardly in the separator.

6. In combination with a pump having a horizontal impeller shaft, a drum-like separating chamber surrounding the pump and having its axis of revolution substantially parallel to and above the axis of the pump and having a discharge connection at its side wall below the top wall.

7. In a pump the combination of a pump casing having a channel, an impeller having buckets cooperating with said channel to drive fluid along the same, a shaft for the impeller entering said casing, said casing having a discharge passageway extending from the channel and a second passageway also extending from said channel, a separating chamber extending partially above and partially below said shaft, said second passageway opening into the lower part of the chamber and the discharge passageway opening into the chamber above the point of opening of the second passageway into the chamber, said chamber having a lateral outlet above the point of opening of the discharge passageway into the chamber.

8. In combination with a pump comprising a casing having a channel, a runner having buckets cooperating with the channel, a discharge passageway and a reentry passageway, of a separator having a curved Wall arched vertically on a radius greater than the radius of said channel to present a downward concavity, said discharge passageway being directed into the separator in a direction to drive the stream of a mixture of liquid and gas along said curved wall for causing the freeing of gas from the liquid by centrifugal effect, said gas being driven inward radially from said curved wall, said separator having a lateral outlet below and radially inwardly from said arched wall for conducting away air freed from the concave side of the stream, the air free liquid of said stream then returning to said channel through said reentry passageway.

9. The method of evacuating a pump of gas in order to prime the intake thereof which comprises mixing liquid and air in the pump casing, driving the mixture out of the pump casing in a stream, conducting said stream in a single turn upwardly arched curved path of long radius to form a large free surface facing downwardly, forcing gas from said mixture and freeing the same at said downwardly directed surface, conducting the gas away from said gas freeing surface and returning the liquid from which gas has been liberated into the pump casing.

10. The method of evacuating a pump of gas to prime the intake thereof which comprises mixing liquid and air in the pump casing, discharging the mixture from the pump casing in a stream, directing the stream in an upwardly arched single turn path of long radius and with a downwardly facing'concave free surface, forcing gas toward said free surface by centrifugal action, checking the velocity of the stream to cause it to assume an upwardly facing free surface under the first free surface, liberating gas from both of said free surfaces, conducting said gas away laterally from between said surfaces and returning the liquid from which gas has been liberated into the pump casing.

HARRY E. LA BOUR.

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