US2790393A - Priming valve assembly - Google Patents

Description

April 30, 1957 D. F. THOMAS L PRIMING VALVE ASSEMBLY 2 Sheets-Sheet 1 Q N% w M I J QM .3 m6 @n w mu N w% hm 4 MW ,nm 3 Q @Q N w AV/V \N %N 'INVENTORI David E Thomas fiober'z 4. Hi/l April 30, 1957 D. F. THOMAS ET AL PRIMING VALVE ASSEMBLY 2 Sheets-Sheet 2 Filed March 29, 1952 I INVENTOR David I? Thomas Robert ,4. H/'// BY 1 @um I QORNEY PG VALVE ASSEMBLY David: F. Thomas, West St, Paul;. and Robert Hill,- Minneapolis, Minn, assignorstmWaterous ornpany; St. Paul,

Application March 29, 19s2,sen=l1Ne.279,331;

8.Claims.. or. roe-1.1a

This invention relates to an" improvement. in p systems for centrifugal pumps'anddealsp'articular a. means for controlling'the flow from a cehtiifiig'alpufrip to the primingpump.

Centrifugal pumps used for. fire fighting "and siinnarpnrposes usually employa gear driven priming pumpwhich is. powered. by the engine used to drive the. centrifugal pump. These pumps are often connected tothe drive shaftof afire engine or similar vehicle and'include: ear ing which selectively connects the wheels of=the vehicle to. the engine, connects the pump impellers to tlie. engine, or connects the gear pump. to the-engine. Inthe event the. pump loses its prime,,it is ordinarily" necessary to shift'these gears in orderto again start the. priming pump into operation. Thespresentiinventiondeals withia'sys torn by. meansof which the priming pumpmaybe actuatedwithout the necessity ofshiftingthedrive gears An object of the present invention .lies in the; provision of a valve whichrcontrols theflow of air. and liquidfroni a centrifugal pump. tothepriming. pum'p. This:valve:--is connected. to the. upper. portions ot the centrifugal pump and also-to thepriming pumpso as. toprovide-an= open passage. between the two pumps during the evae-uation of ail-from the centrifugal pump The valveais-sorarranged as to. seal thepassagebetween .the pumpsafter -the-com= pletion of. the priming operation.

A feature of the present invention resides in the-pro= vision-of apistonvalve. having a casing provided with a plurality; ofnbossesarrangedain a plane -nor-rnalito the axis .ofnthe piston.. The alve :pistonis provided with a lobewhichzseal" these. ports from .oneanother ini closed position of-the valve.. An axially'spacedport connects the valvecasing to. the "passage leading to thew-priming pump. Upon movement of the piston valve in one di rection, an open connection is provided between the1-angu= larly, spaced ports and: the axially spaced porttso'that" air maybe. drawn from all of the 'angularlyspaced portsf A feature. of =.the..present invention lies: in ithe provision of. avalve having: a plurality of iangular'ly'spaced ports in. the valve casing on a plan "normal to :the axisf'oftlie valve. :piston and in connecting cer-tainrof these": ports to" the. suction chambers above-theimpeller eyes='so' as=to provide a means 'of evacuating air from .thesuction ch'arn bers above the. impeller eyes; A-third port"is cori'n'ected to the top of the dischargetpipeof the'pumpa: Tlj yd 'p ingthe-priming operation airimay be evacuated 'b'o'th from the suction chambers and the dischargeapipei A: furthersfeature of :the: present invention 'lis iii-fille provision or-11a priming valve equipped with a "switch for closing: an electric'circu-it toa p rirning'jrnotorwhen the valve=- is in" one position; Thus in "order'tofprimei the pump, it is only necessary to actuate the .valve "piston in a-manner-to-connect theintake of the"printin'gpurnp1 to the ports connected to the suction chambers 'andthe d charge -pipe-of"thecentrifugal'pump. As the val'v '1s moved into open" position the circuit is closed to: the

priming motor'or to a relay controlling the primingniofor" nited States Patent 2,790,393 Patented Apr. 30, 1955'? 2 errant; thereby automatically actuating the priming p mp- These and other objects and novelfeatures of the present invention will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of the specifications:

Figure l is a vertical sectional view through the cerit'rifugal pump showing the relationship of parts therein.

Figure} is a horizontal s'ectionalview through a portioii' of the gearbox and the priming pump showing the relationship o'f'parts therein in the plane on line 22 of Fig. l.

Figure 3 isa cross sectional view through the priming valvedniline 3'30f Fig. 1.

Figure 4 is a transverse section through the priming v'aiv; the pos'ition of the section being indicated by the line 44 of Figure 3.

Figdri is a wiring diagram showing the manner in whichthevalve switch may be-employed to actuate the pidhiihgi riibtoi. V

Thecehtrifugal pump A shown in Figures 1 and 2 of the drawings-istypical of the type of pump for which thefpr'imin g valve is designed. I i I The'fpump A includes an impeller shaft 10, which in thep'um'p' illustrated, supportsa pairof impellers 11 and 12.: A pumpcasing 1'3'enclo ses the impellers and pro vids t'wdvolutes 141 and 15 encircling the impellers. The purrip'lioiising 1-3 also may incorporate discharge and ihtake manifolds, the discharge manifold beingfindi= ca'ted at'16; The intake manifold is connected to two suction chambers 17 and 19 which are arrangedoutwardly of'theimpellers 11- and 12. The impeller eyesZD and 21 communicate with the suction chambers 17 and 19 tor'e ceive liquid therefrom. The impellers may be corinect diri series; orin parallel and in either event deliver liquid underpressure to the discharge pipe or manifol dflfifv In thepump. illustrated the impellershaft 10 is'dr'iven byaage ar Z Z supported in a gear case or housing 23. The gear 22 isin mesh with an idler gear '24 mounted uponashaft 25supportedby the gear case23 in parallel relation to the impeller shaft 10. The gear case 23 also supports adrive shaft"26which projects forwardly from the gear case and is normally connected to' the engine of: thepump supporting vehiclel' The drive shaft 26 is splinedas indicated"at 27 internally of the gear case and slidably supports a drive gear 29. In the'p'osition il-' lustrated in Figure 1 of thedrawi'ngs; the gear 29 is con nected to, or in mesh with'the idler gear '24 and accordinglyis in *positionto drive the centrifugal pump.

The-slidable gear 29 is provided with a hub 36 equipped withanexternal groove 31. A shifting fork 32 (Figure 2 of the drawings) is mounted upon aslidable shaft 33 supported by the gear case 23 laterally from the drive shaft. The shaft 33 is controlled by any suitable shift ice inggmechanism and acts'to slide the gear 29 longitudinally of-the-drive shaft 26. In the form of construction illustrated a power receiving shaft 34 is rotatably supported byr'the gear casing .23 in" axial alignment with the drive shaft 26n Thepower receiving shaft '34jis provided with externalw clutchor gear teeth 35 on-its inner extremity Internal teeth '36 are provided on within the gear case.- thegear-"29 which are engageable with"thej teeth 35.

Thus: the teeth 35'and 36 provide a'clu'tch'for connecting 31 is supportedsby the gear'caseqzii in-parallel relation"- tothe-drive sn eze, gear 38 encircles the drive shaft 37. This gear 38 is engageable with the slidable gear 29 in one position thereof. In Figure 2 of the drawings the gear 29 has been moved laterally from the position shown in Figure 1 and the priming pump gear is in mesh with the drive gear 29 in this position.

The priming pump casing 41 is connected to, or is integral with, a portion of the gear case 23. The casing 40 accommodates an end of the priming pump drive shaft 37, as well as a parallel shaft 39. Inter-engaging impellers 41 and 42 are supported upon the shafts 37 and 39 respectively for rotation in unison therewith. These impellers 41 and 42 may be in the form of gears similar to those used in gear pumps or may have other types of inter-engaging lobes which positively draw air and liquid from a supply source and force it through a pump outlet. In the priming pump arrangement illustrated the inlet of the priming pump is connected to the valve to withdraw air and water therefrom. The outlet of the pump ordinarily leads to a drain pipe and to atmosphere.

An electric motor 43 is supported on the gear case 23 with the motor shaft 44 in axial alignment with the gear pump drive shaft 37. The motor shaft is connected to the drive shaft 37 through a sleeve type coupling 45. The coupling 45 is pinned or otherwise connected to the motor shaft 44 and is also keyed to the drive shaft 37 to form a connection between these parts. The gear 38 encircles the drive shaft 37 and is connected thereto through an overrunning clutch 46.

From the foregoing explanation, it will be obvious that the priming pump may be actuated either by the gear 29 driven by the vehicle engine, or may be driven by the electric motor 43. Thus the power from the vehicle engine may be used to prime the pump in the event of failure of the electric motor 43 or in the lack of a suitable source of current supply.

A valve B is supported above the centrifugal pump A as illustrated in Figure 1 of the drawings. The manner in which this valve is connected to the parts of the pump will be described following a description of the valve per se. The details of construction of the valve are best seen in Figures 3 and 4 of the drawings.

As best noted in these figures the valve B includes an elongated tubular valve body 47 having an elongated cylinder 49 extending therethrough. This cylinder is designed to support the piston or plunger which is indicated in general by the numeral 50. The plunger 50 includes a pair of piston lobes 51 and 52 held in spaced relation by a reduced diameter plunger 53. A boss 54 extends from one end of the piston lobe 51 and is directed to the adjacent end of the valve body 47. A closure plate 55 is secured to the end of the valve body by machine screws 56 or other suitable means. A spring 57 is interposed between the piston lobe 51 and the closure plate 55 and tends to bias the plunger 53 toward the right as viewed in Figure 3. The spring 57 encircles the boss 54 and is guided at one end thereby.

A switch 59 is provided with an operating plunger 60 which projects from the switch housing through a threaded sleeve 61. A collar 62 is threaded onto the sleeve 61 and acts to hold the switch with the sleeve 61 projecting through an axial aperture in the closure plate 55. The spring 57 encircles the collar 62 and is guided at its outer end thereby. The plunger 60 projects toward the boss 54 and is designed for actuation thereby in one extreme position of the piston plunger.

The valve cylinder 49 is provided with longitudinally spaced peripheral grooves 63, 64 and 65 which are designed to accommodate O- rings 66, 67, and 69 respectively. These rings are designed to seal against the piston lobes and to prevent leakage longitudinally of the valvec-ylinder. V V

As best indicated in Figure 4 of the drawings the valve housing 47 is provided with three angularly spaced bosses 70, 71 and 72. These bosses are provided with internally threaded ports 73, 74 and 75 respectively. The ports extend in a radial direction and the axes of the ports are arranged on a common plane which is normal to the axis of the piston plunger. The ports are located between the O- rings 66 and 67 so that the O-rings seal against the piston lobe 51 on opposite sides of the ports to prevent leakage of liquid longitudinally of the valve. It is possible for slight leakage to take place about the periphery of the piston lobe 51 and fluid under pressure can leak slightly to the two ports connected to the suction chambers of the pump. However, the amount of leakage is so small as to be negligible from a practical standpoint.

As noted in Figure 3 of the drawings the O-ring 69 engages the piston lobe 52 and remains in engagement therewith throughout the extent of travel of the piston plunger. Thus in both extreme positions of the valve, leakage through the open rear end of the valv i prevented. The O-ring 66 also, at all times, remains in sealing relation to the piston lobe 51, and thus a continuous seal is provided to prevent the escape of fluid through the left hand end of the valve body.

The boss 72 projecting from the valve body is elongated longitudinally of the valve and accommodates a second port 76 longitudinally spaced from the port 75. The port 76 communicates with the interior of the valve cylinder 49 between the piston lobes 51 and 52. When the piston lobes are in the position shown in Figure 3, the port 76 is not in communication with any of the other valve ports. However, when the piston plunger 53 is moved to the left from the position illustrated to its opposite extreme position, the port 76 is connected to all of the other ports 73, 74 and 75.

A valve operating rod 77 is threaded into or otherwise connected to the piston lobe 52 for actuation of the piston plunger. An extension 79 of the operating rod 77 extends through the mounting panel 80 and is provided with an operating handle by means of which the rod may be reciprocated. The valve plunger is normally biased to the extreme position illustrated in Figure 3 of the drawings by the spring 57. However, the rod may be moved manually to the left as viewed in Figure 3 to move the plunger into its opposite extreme position. In this case there is a direct connection between all of the ports 73, 74, 75 and 76.

Figure 5 illustrates a manner in which the switch is connected in circuit to control the circuit to the priming motor 43. The switch 59 is connected by a conductor 81 to one side of the power supply 82 which is indicated as the vehicle battery. The other switch contact is connected by a conductor 83 to the release coil 84, the other terminal of which is grounded at 85. The relay coil actuates a relay armature 86 which may close a normally open circuit by engaging the contact 87 which is connected to the battery 82 through conductor 81. The relay armature 86 is connected by conductor 89 to one terminal of the motor 43, the other terminal of which is grounded at 90. The remaining terminal of the battery 82 is grounded at 91 to complete the circuit. Obviously, when the switch 59 is actuated a circuit is closed to energize the relay coil 84. Actuation of the coil moves the relay armature 86 in position to close a circuit to the priming motor 43.

The operation of the apparatus is quite obvious from the foregoing description. The valve port 73 is connected by a tubular connection 92 to the upper extremity of the suction chamber 17 above the impeller eye 20. The port 74 is connected by a tubular connection 93 to the upper extremity of the suction chamber 19 above the suction eye 21. The valve port 75 is connected by a tubular connection 94 to the upper extremity of the discharge manifold 16.

When the pump is started into operation the drive shaft 26 may be connected through the gear 29 to the impeller shaft 10 to rotate the pump impellers. The valve operating rod 77 is moved longimdinally to shift Women's the valveplunger from the position shown in Eigpre 3 toits opposite extreme position. This'actionopens the connectionbetween-the tubular conduits 92, 93 and194 and the valve port-76 which is connected by a pipe 95 to the inlet of thepriming pump; Also as the operating rod 77 is actuated the boss 54 engages a push button 60 which closes the switch 59 and accordinglytclosesithe relay circuit which in turn actuates the priming motor 43.

The operating rod 77 may be either held in priming position or may be provided with locking means to hold the priming valve in open position. The priming motor remains energized until air has been evacuated from the suction chambers of the pump A and from the discharge manifold thereof. At this time the priming pump tends to draw water from the centrifugal pump, providing an indication that the pump has been properly primed. The operating rod 77 may then be released and the priming valve closed until it is again required to prime the pump.

Any tendency for the valve to move longitudinally of its cylinder due to pressures existing within the valve body is obviated by the two lobe construction. The pressure within the valve always acts upon equal sized areas on the piston lobes. The valve is thus balanced in its action and does not move in either direction due to pressures experienced within the valve body.

In accordance with the patent statutes, the principles of construction and operation of the priming system for centrifugal pumps has been described, and while it has been endeavored to set forth the best embodiments there of, it is desired to have it understood that these are only illustrative thereof and that obvious changes may be made within the scope of the following claims without departing from the spirit of the present invention.

We claim:

1. A pump priming system including in combination with a centrifugal pump provided with a suction chamber, impeller eye and discharge manifold, a priming pump, a valve, means connecting the valve to the discharge manifold of the centrifugal pump and to the suction chamber thereof at a point above the impeller eye, means connecting the valve to the priming pump, said valve being operable between two positions to either seal the connections from the discharge manifold and suction chamber from the connection with the priming pump or to provide communication therebetween, interengaging gear driving means for said centrifugal pump and said priming pump, and auxiliary electric driving means for said priming pump.

2. A priming system including in combination with a centrifugal pump provided with a suction chamber and a discharge manifold a priming pump, a valve having a valve chamber, a connection between said chamber and the discharge manifold and suction chamber of the centrifugal pump, said valve chamber also having a connection with the intake of the priming pump, said valve in one position sealing each of said connections from the others, and in the other extreme position connecting all of said connections, interengaging gear driving means for said centrifugal pump and said priming pump, auxiliary electric driving means for said priming pump, and control means operable by said valve to start and stop said auxiliary electric driving means.

3. A priming system including in combination with a centrifugal pump provided with suction chambers, impeller chambers and a discharge manifold a priming pump, the priming pump having a pair of impellers communicating with the discharge manifold and said suction chambers communicating with the impeller eyes, a valve having a valve chamber, said chamber being connected to each suction chamber of the centrifugal pump above the level of the impeller eye, and said valve chamber also being connected to the centrifugal pump discharge manifold, the valve chamber also being conneced to the intake of the priming pump, and means in said valve chamber to selectively seal each of said connections from the remaining connections or to open all of said connections into communication with all other connections, electric control means operated by said valve, interengaging; gear driving means for said centrifugal pump and saidgprimingpump, and auxiliary electric driving, means for said priming pump, ,controlled'by', said electrio control means operated by said valve.

l 4. Alfpump priming system includingin combination with a centrifugal pump having a pair of impellers, suction chambers connected to the impeller eyes of each of said impellers, a discharge manifold, and a priming pump, a valve connected to the said centrifugal pump and also to the priming pump including a body having a valve cylinder therein, said body having a series of angularly spaced ports therein communicating with the valve cylinder and arranged substantially on a plane normal to the axis of the cylinder, tubular connections from said angularly spaced ports to the discharge manifold and to the suction chambers of the centrifugal pump above the level of the impeller eyes, said valve chamber having an additional valve port in axially spaced relation from the plane of the previously described ports, a valve plunger operable in said valve chamber and movable longitudinally thereof, said plunger operating in one position to seal said angularly spaced ports from each other and from said axially spaced port and operable in another position to uncover said ports to provide a connection therebetween, gear driving means for said centrifugal pump, and auxiliary driving means for said priming pump.

5. The structure described in claim 4 and in which the plunger includes two spaced piston lobes and means connecting said lobes in spaced relation, one of the piston lobes forming the seal between said angularly spaced ports in one position thereof, said spaced lobes extending on opposite sides of all of said angular ports in open position of the valve.

6. A pump priming system including in combination with a centrifugal pump, a priming pump, and inner engaging gear means for simultaneously driving said pumps, a valve including a body having a series of ports therein, certain of said ports being connected to said centrifugal pump to evacuate air therefrom, and another of said ports connected to said priming pump to deliver air and liquid thereto, the valve including a slidable plunger for selectively sealing said ports from one another or for connecting said ports, an auxiliary electric priming pump motor connected to said priming pump to actuate the same, a circuit to said electric motor, and a switch in said circuit, said switch being in the path of movement of said slidable plunger for actuation thereby.

7. A pump priming system including in combination with a centrifugal pump, a priming pump and an electrically operated driving motor for said priming pump, a priming valve having an elongated tubular body provided with a bore therethro-ugh, a plunger slidably supported in said bore, said plunger including a pair of spaced piston lobes in sealing relation with said bore and means supporting said lobes in spaced relation, a series of angularly spaced ports arranged on a plane sub stantially normal to the axis of the bore, said ports being sealed one from another by one of said piston lobes in one extreme position of said plunger, an additional valve port in the body in axially spaced relation to the remaining ports, said additional port being communicable with the first named ports in another position of said plunger between said piston lobes, and a switch for controlling said electric driving motor for said priming pump including a switch actuating member arranged in the path of movement of said plunger for actuation thereby in said other position of said plunger.

8. The structure described in claim 7 and including means for biasing said valve plunger toward closed posi-.

tion in which said angularly spaced ports are sealed 2,237,577 Ray Apr. 8, 1941 from one another. 2,275,500 Broadhurst Mar. 10, 1942 2,329,495 Van Pelt Sept. 14, 1943 References Cited in the file of this patent 2,391,898 Hobbs 194.6

5 l fi O t- 3,

644,473 Sellers Feb. 27, 1900 FOREIGN PATENTS 7 1,573,931 Goyne Feb. 23, 1926 534,901, 'Great Britain Mar. 21, 1941 1,629,554 Thompson May 24, 1927

Images