US1529005A - Method of and means for operating valves - Google Patents

Description

March l0, 1925. 1,529,005

. C. H. BECKWITH METHOD OF AND MEANS FOR OPERATING VALVES Fild-Sepi..v 10. 1925 2 Sheets-Sheet l {gaas-J6 4 March 10. 1925. 1,529,005

c. H. BEcKwl'rH METHOD'OF AND MEANS FOR OPERATING VALVES Filed Sept. l0, 1923 2 Sheets-Sheet 2 C ff if CLOSE x O x x x x o o UWT o x x x x O x x STOFOXOOOOXX 5 CLOSE 6g 2 6g 5 671/56 LlMIT W' Zwan/2507*,"

- To aZZ whom it may concern: v

Patentes Mar. 10,111925.

MUNITED STATES PATENT oFF ICE.

CLINTON H. BEGKWITH, OF CHICAGO, ILLINOIS, ASSIGNOR T0 C RANE CO., OF CHICAGO,

' ILLINOIS, A CORPORATION OF ILLINOIS.

METHOD OF AND MEANS FOR OPERATING VALVES.`

Application med September Be it known that I, CLINTON H. BECK- wIT'H, a Citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Methods of and Means for Operating Valves, of which the following is a specilication.`

This invention pertains generally to valve operatingmechanis'ms, andwhile the principles of my invention may be utilized for various purposes,4` the invention is herein shown, merely for illustrative purposes, asv

employed in connection with a motor operated gate valve.

' It has heretofore been the common practice. so far as I am aware, to operate valves of this character by a motor, in the power circuit of which was interposed a throwout switch vintended to be automatically opened so as to shutoff the power supply to the motor at the exact instant that the valve reached its seat. These constructions, however, have not been satisfactory in practicaloperat-ion for the reason that the'valve does not close against its seat successively in the same position. The result has been, therefore, that if the switch was thrown out so that the closing movement, of the valveV stopped before the lvalve was fully seated,l leakage past the valve inevitably occurred,

particularly under high pressure duty. On the'othemhand, if, as the result of a slight accumulation of sediment or other forelgn matter on the valve or the seat, the valve should jam before it reached the limit of movement for which the switch was set, in

that event the motor would stall, the throwout switchwouldzfail to operate at all, and unless thev difficulty were immediatelv discovered, the motor windings wou d be burnedout.

"zOne of the primary purposes of my present yinvention is to obvia-te the difliculties :and uncertainties of operation, above mentioned, by providin a method and-,means for operating the .va ve, which will not onl insure that the valve is fully seated at eac closing operation, but will also insure against injury to the motor windings, and to other members of the valve operating mechanism, which would result if the current were left on the motor for any-con siderablelength of time after the same had 1o, i923. serial No. 661,747.

Another object of the invention is to overcome the danger of damaging the valve seats, due to the inertia of the moving parts added to the torque of the motor at the end of the travel.

With these ends in view, my invention is designed to utilize the full speed and torque of t e motor for moving the valve throughout the major portion of its travel and up to a. predetermined point in the travel` slightly before the actual seating occurs.v AtA this point the torque and speedof the motor are automatically reduced 'so that the valve will be positively forced against its seat, but under reduced power, vwhich is not great enough to cause injur'y to-th'e valve, its seat, or the operatin mechanism when movement of the valve 1s finally stopped, by intima-te and leak tight engagement between the valve and seat. When this point is reached and further movement of the valve the current to the motor was reduced, and is designed to automatically shut off the currentto the motor at the expiration of a predetermined period of time after the relay goes into operation.

In addition to this method of closing the valve, which insures a positive and leak tight closing at each actuation, and also precludes injury both to the motor and the operating mechanisms, as well as to the valve and'its seat, my invention contemplates an improved method and means'of positively breaking or jerking the valve away from its seat, for opening purposes, without imposing excessive strains either upon the motor or the other parts of the operating mechanism.

Another feature of my invention resides in the'adjustability of the operating means, which enables thereduction' ot'` current to the motor to be effected at the'most desirable point in the travel of the valve so as to result in the most efficient and reliable operation of the'apparatus.

Other objects and advantages of my invention,l in addition to compactnss of assembly, economy in manufacture and installation, and reliability of operation, should be readily appreciated as the invention becomes better understood by reference to the following description, when considered in connection with the accompanying drawings.'

Referring to the drawings: Fig. 1 is a lside elevation, partially in vertical section, illustrating a means for carrying my improved method into eifect;

Fig. 2 is a sectional view on the line 2-2 of Fig. l; A Figs 3-is a sectional view on the line 3-3 of Fig..2;

circuit.

Fig. 4 is a sectional view on theline 4-4 of Fig. 1; f

Fig. 5 is a diagrammatic viewo'f the control circuit for closing the valve;

Fig. 6 is a chart illustrating the position of the various switches during an operation cycle; and

` Fig. 7 illustrates diagrammatically the introduction of the resistance in the motor Referring to the drawings more in detail,

and particularly to Figs. l to 4, inclusive,

thereof, reference character 8 indicates the casing of a gate valve equipped with a valve seat 9. Upon the bonnet 11 of the valve casing is mounted a .standard or yoke 12,

through which the valve stem 13, carrying at its lower end the valve 14, extends. The

-upper portion of the valve stem is threaded and engaged by a' rotatable sleevey nut 15, provided at one side with a radially projectinglug 16. The hub 17 of a gear 18 rotatgear 18 meshes with and is driven by a pin-` lion- 24, Jmounted upon the upper end of a `shaft 25, which carries a gear 26 at its lower end, in turn meshing with and driven by a pinion 27, fixed upon the shaft of a motor 28, which is mounted upon the standard 12.

Assuming that the parts are in the position shown in Figs. v1 and 4, with the valve closed against its seat, if the motor is now started, the Igear 18 and-,its hub 17 will be rotated in a. `,counter-clockwise direction, viewing Fig. 4. Since during practically a [complete revolution of the hub 17 'substantially no resistance `is offered to its movement, the motor during this period will be permitted to speed up and attain considerable momentum, which, when the lug 19 finally engages the lug 16, is applied 'as av hammer` blow against the nut 154 to break f valve away from its seat were produced by a steady torque exerted through a continuous connection which did notinclude the lost motion connection provided between the sleeve 15 and the hub 17.

Upon the standard 12 there is also mounted a limit switch housing 29, within which is disposed ay limitswitch comprising a threaded rod 31, engaged by a nut 32 which travels longitudinally of the rod when the rod 'is rotated. The upper end of the rod projects above the housing 29, and has mounted thereon a gear wheel 33, which meshes with and is driven bya gear 34 secured by -a key 35 to the sleeve nut 15. Rotary movements of this sleeve nut lare therefore transmitted to the threaded rod 31 to cause movement of the lnut 32 longitudinally of the rod. A stationary guide rod 36 extends through the nut 32 to prevent rotation of the nut.

The nut32 carries a pair of adjustable abutment screws 37 and 38, projecting downwardly and upwardly, respectively, from the nut. Near the lower end of and within the housing 29 there is mounteda contact switch', designated generally by reference character A. The switch comprises a stationary Contact piece 39 and a movable contact member 41, carried upon a bell crank lever fulcrumed at' 42 upon an insulated 'block 43. 'An abutment 44, mounted u on one arm ofthe bell crank member, is' isposed in the path of travel of the abutment screw 37, and this abutment is Connected. by

a wire 45` with a binding post 46 connected to thecircuit wire 47, as will be-l later eX- 'plained The contact member 39 is con` nected withthe circuit wire 48.

YVithin the `upper portionof the housing 29 there is mounteda similar contact switch B, the structural details of which are generally similar tothe switch A, just described,

It will be apparent, therefore, that upon l closing movement of the valve 14, 'the limit switch nut 32 will travel downwardly upon the rod 31, until,y through the abutment screw 37, the Contact switch A is opened; and that upon opening movement of the valve, the nut 32 will travel upwardly upon 'the rod 31 until, through the abutment screw 38, the contact switch B is opened.-

The control of the motor, by which the method of closinglthe'valve, preLviously cX- plained, is carried out, will be best understood by reference to the diagrammatic dis-V closure of Fig. 5. Referring to this figure,

, illustrated diagrainmatically only, and that standard or other preferred apparatus may be employed in the circuit to accomplish the desired results. It should further be understood that the circuit is illustrative merely, `the one shown in Fig.V 5v being adapted for a D. C. reversible motor; whereas, if an A. C. motor be employed, a different hook-up would be required, althougli the principles of operation and the results secured would be the same as are obtained with the D. C. hook-up shown herein merely as illustrating the principles of my. invention.

Assuming that the valve is in fully opened position, that the switch 53 is open, and that the circuit is dead, the first operation in closing the valve is to close the switch 53, which is ydone manually. Current will now4 fiow through the wires 54 and 55 through the solenoid 56, the contact switch C, and the wire 57, establishing a circuit which energizes the solenoid 56 to close the normally open contact switches D and E. At the same time a circuit is closed through wires 54, 55, 58,-the solenoid 59, wire 6l, solenoid 62, wire-47,!switch A, wire48, and wire 63 to energize solenoid 59, thereby closing contact switch F, and opening contact switch G, and atl the same time energizing solenoid 62, to open the normally closed (ontact switch H. As soon as contact switches D, E are closed, current will be fed directly to the motor 28 through the `circuit, including the Wires 64, 65, the switch F, and wire66, as illustrated in the upper y diagrami niark Close in Fig. -7. The motor will vtherefore operate at full speed and torque .to move the valve toward closed position. The'nut 32 of the limit switch .will simultaneouslytravel downwardly upon the revolving threaded rod 31, and when the valve has reached a predetermined position in proximity toits seat, determined by the adjustment ofthe abutmentscrew 37, this screw will engageV the abutment 44 of the switch A, thereby swinging the movable member of the switch on its fulcrum 42 to open the switch and break the circuit in which it is included.

VThe breaking of this circuit' de-energizes the solenoid 59, 'thereby permitting -the switch memberl controlled thereby toY resume the normal position shown in Fig. 5, opening the circuit through the switch' F and closing the circuit through the switch G. -This action imposes resistance 67 in series with the motor, and resistance 68 in parallel with the motor through the switch G, as shown in Fig. 5, and as illustrated diagrammatically in the second position shown in Fig. 7, and indicated Limit The iinposition ofV these series and parallel resistances in the motor circuit reduces both the speed and torque of the motor, which contlnues to operate, however, to force the valve against its seat. Since the final closing movementofthe valve is effected under reduced speed -and torque of the motor, the valve will not be jammed so violently `.against its seat as to -cause injury to the operating mechanism. When the valve'becomesfully seated so that further movement thereof is precluded, the motor will stall, but because current is being supplied thereto only in ymaterially reduced quantities there is no liability of the motor coils becoming the motor becomes stalle The breaking of the circuit in whichthe switch A is included also cle-energizes the solenoid 62, which thereupon releases the movable member of the switch H, kpermitburned` out or even unduly overheated when 'ting this switch to resume its normal closed position, as shown in Fig. 5. The closing vof this switch sets in operation a time rela 69, included in the circuit with the swi'tc H, which relay, after a predetermined period of time for which yit is designed has elapsed, will actuate the movable member of the switch C to open this switch. Since the time 'relay 69 is a commercial article, of which any one of several types may be'employed, the details thereof are not illustrated herein, it being sufficient for an understanding of the present invention to comprehend that a delayed action is yinvolved so that when a circuit is established through the relay, some little time, in the present instance a few seconds, elapses before the switch C is opened by the relay. In the 4present instance the relay is so designed that the switch ,C will not be opened until after the valve has been fully closed and the operating motor has become stalled. The opening of the switch C de-energizes the solenoid 56, thereby permitting the movable members ofthe switches Dand la) to resume their normal open position, so as to shut off the'current to the motor. The switch 53 may then either be manually opened, or preferably is automatically opened by the opening of the switches D and E. if

' The position of the various contact switches during the cycle' is illustrated dia-- grammatically in Fig. 6, from which it will be observed that when the closing movement of the valve is started by throwinor in the main line switch 53, contacts A, C), D, E, and F are either already or become immediately closed in the-manner previously described, while contact B remains open under the infiuence ofthe abutment screw 38, and contacts G and H become immediately opened through energizing of the solenoids 59and 62, as previously described. pon

closing movement of the valve, contact B closes as soon as screw 38 is withdrawn therefrom. When the valve reaches a point in proximity to its seat, at which point screw 37 opens switch A, thereby de-energizing solenoids 59v and 62, switch F opens, and

switches G and- Hy close. lVhen the time relay 69 operates, all of the switchas, with the exception of B, G, and H, which 'are normally closed, open and the circuit remains dead until the main switch 53 is again closed.

I have shown herein thc closing circuit only,.but it should be understood that the v wire 71, connected with th'e'stationary inemldescribed, and the time relay is set in operation to Vshut oil' the current after the valve has opened and the motor is stalled. It should be remembered also that when the apparatus is started for the purpose of opening the valve, the motor'speeds up and attains considerable momentum before stud 19 engagesstud 16 to unseat the valve with a hammer blow,'and obviously, when the motor is reversed t0 close the valve, a similar hammer blow in a reverse direction is im parted to start thevalve on its downward travel.

It is believed that-my improved method, and a preferred means for carrying the same into effect, will be understoodiand its ad` vantages appreciated' from the foregoingwithout vfurther description, and it should be manifest that the structuralA details illustrated and described may be varied within wide limits without exceeding the scope of the invention, as defined inthe following claims.

I claim: l 1. The method of operating a valve which comprises moving the-valve under full power into :proximity to its seat, closing the valve' against its seat under reduced power,

and thereafterv automatically relieving the.

`closed valve fromthe closing power. v

2 The method of operating a valvewhicliv consists inI al plyingmaximum closing power tothe va ves-,until a pointin proximity tothe valve seat isreached. by the valve, reducin .fthe closing: power during the remain er of the closing movement, and terminatjiiVethe application of power to the valve a r'thesame 'has been completely automatically causing the cessation of said effort.

l 4. The method of operating a valve which consists in imposing a previously acquired momentum on the valve to start the same inl motion, continuing the motion of ,the valveunder a predetermined motive effort to a predetermined point in its travel, applying a reduced motive eiort to eiect the final closing movement of the valve, and automatically causing the cessation of said motive eifort. after the motion of the valve has ceased.

5. The combination with a valve, of means including a motor and a 'control therefor, for moving said valve under full power toward its seat to a predetermined point, then completing the closing lmovement of the valve under reducedV power, 'and finally automatically shutting off the power after the valve is seated.

6. The combination with a valve, of a motor connected thereto to operate the same, mea-ns for reducing the effective torque of said motor when the valve reaches-apre# determined point in its travel, and means.

olf the appllcai'or automaticallyshutti tion of. power to theE mo or at the expira tion of a predetermined time after said predetermined pointhas been reached by said valve.

7. The combination with a valve, of am" motor. driving means including a lost motionconnection between said motor and said valve and a control for said motor including a limit switch for imposing' resistance -in the motor circuit and a time relay for 'shutting oi the motor a predetermmed time after said limit switch operates.

8."Tl1`e combination with a -.valve, of a motor, an operative connection between said motor` and saidvalve. and a controlforssaid valve including means for introducmg parallel and series resistance into the motor circuit at a predetermined. point in Athe travel of the valve and a time relay rendered operable by said last mentioned means for shutting otl the current to said motor afvter the valve has become' fullyv seated. and

vthe motor is stalled.

9. The combination with a valvet' of an operating motor'therefor, and control means for said motor for reducing the speed and torque of the motor as-the valve approaches its seat and for shutting oi the power to the :(riotor afterthe valve has been fully seate Y CLINTON n eEcKwITH.'

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