US2961968A

US2961968A - Centrifugal pump and priming pump assembly

Info

Publication number: US2961968A
Application number: US748303A
Authority: US
Inventors: David F Thomas; Robert A Hill
Original assignee: Waterous Co
Current assignee: Waterous Co
Priority date: 1956-02-02
Filing date: 1958-07-14
Publication date: 1960-11-29
Anticipated expiration: 1977-11-29

Description

Nov. 29, 1960 D. F. rHoMAs ETA; 2,961,968

CENTRIFUGAL PUMP AND PRIMING APUMP ASSEMBLY 4 Sheets-Sheet 1 Original Filed Feb. 2, 1956 Nov.29,1960 D'. F. THOMAS am 2,961,968

CEN'I'RIFUGAL PUMP AND PRIMING PUMP ASSEMBLY* original Filed Feb. 2, 195s 4 snees-snegt 2- f/ m if f if l 31- 4 j] Ha 3 INVENTOR MWQM AORNEY NOV- 29, 1960 D. F. THoMAs ETAL CENTRIFUGL PUMP AND PRIMING PUMP SSEMBLY 4 sheets-sheet s Original Filed Feb. 2, 195.6

NNN! BY @M /@m ATTORNEY Nov. 29, 1960 n. F. THOMAS ETAL 2,961,968

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. w N MQ NWN I N VE NTOR NN @QN NNN WN WQN NWN %WN NWN @MN NWN mg ma@ M. N @WN @QN aV/'c/ F 7770/7705 Faber/ /7/'// BY m n e9.

ATTORNEY Patented Nov. k249, 19611 CENTRIFUGAL PUMP AND PRIMIN G PUMP ASSEMBLY David F. Thomas, St. Paul, and Robert A. Hill, Minneapolis, Minn., assignors to Waterous Company, St. Paul, Minn., a corporation of Minnesota Original application Feb. 2, 1956, Ser. No. 562,959. Divided and this application `luly 14, 1958, Ser. No. 748,303

3 Claims. (Cl. 10S-113) This invention relates to an improvement in centrifugal pump and priming pump assembly and deals particular- 1y with a means of operating a transfer valve through the use of partial vacuum created by the centrifugal pump priming pump.

Centrifugal pumps of the type used in lire engines and the like are often provided with a plurality of stages which may be connected either in series or in parallel. This is usually accomplished by providing a transfer valve controlling the discharge of a first stage and directing this discharge either to the centrifugal pump discharge manifold or to the intake or suction chamber of the second stage. Various means have been devised for operating transfer valves so that they can be conveniently operated from a remote point. For example, tests have been made using vacuum actuated devices for moving the transfer valve and by employing as a source of partial vacuum, the partial vacuum created in the intake manifold of the vehicle engine. Unfortunately, the partial vacuum created in this intake manifold is not constant and is actually variable between wide limits. Accordingly, it is desirable in a device of this type to provide a source of vacuum which has a tendency to remain constant or at least a source of supply which at all times is capable of producing the desired result.

An object of the present invention resides in the provision of a vacuum actuated apparatus for operating a transfer valve and which derives its source of partial vacuum from a positive displacement priming pump. Centrifugal pumps of the type in question are usually provided with a priming pump capable of drawing water from a water supply into the body of the centrifugal pump in sufficient volume to prime the pump. Pumps of this type are capable of drawing considerable vacuum and this partial vacuum is substantially constant. By connecting the suction side of the priming pump to the transfer valve actuating mechanism, the desirable dependable source of partial vacuum may be obtained.

The present application is a divisional application of our previously tiled application for patent, Serial No. 562,959, filed February 2, 1956, tor Centrifugal Fire Pump.

These andother objects and novel features of the present invention will be more clearly and fully`set forth in the following specification and claims.

11n the drawings forming a part of the specification:

Figure 1 is a vertical sectional View through a centrifugal pump showing in general the arrangement of parts therein.

Figure 2 is a horizontal sectional view through the drive shaft of the pump, the position of the section being indicated by the line 2--2 of Figure 1. Y

Figure 3 is a sectional view through the priming pump and actuating mechanism, the position of the section being indicated by the line 3 3 of Figure 2.

` Figure 4 isa diagrammatic view showing the manner in which the priming pump and transfer valve actuating mechanism are connected.

Figure 5 is a plan View of the pump showing the location of the transfer valve.

Figure 6 is a diagrammatic view showing the manner in which uid may flow through the pump.

The pump includes a housing formed with a main casting 10 and a cover casting 14 which comprise housing portions including intake chambers 11 and 12 and a discharge passage 13. The housing portions 10 and 14 are connected along a parting line on a horizontal plane continuation of the partition wall 19.

22 are mounted upon the shaft 15 within the volutes 16Y The otherconnection including the-'ttings50 armi-$51,;A

through the axis of an impeller shaft 15. The housing portions are shaped to provide volutes 16 and 17 in parallel relation separated by a partition wall 19. Center sealing member 20 is provided inwardly of the partition wall 19 to form a seal about the shaft 15 and to form a Impellers 21 and and 17. These impellers may be of any desired shape having intake ends 23 and 24 communicating with the intake manifolds 11 and 12, respectively. These intake ends work with a running t with outer sealing rings 25 and 26 and

inner sealing hubs

27 and 29, respectively, which are also mounted about the impeller shaft 15.

On either side of the intake manifolds 11 and 12, the casing 10 and the cover 14 extend about the shaft 15 but in spaced relation thereto to form a stuing box at each end of the housing, one such stuiiing box being indicated at 30 and the other being indicated at 32.

Lantern rings

33 and 34 are integral with the

inner sealing members

27 and 29, and packing rings 35 and 36 are positioned outwardly of the lantern rings. A packing gland 37 is provided against the sealing rings 35 and a similar packing gland 39 is provided against the packing rings 36 to form a tight seal about the shaft 15.

Each end of the pump housing is provided with an outboard support, these supports being indicated at 4t) and 41 and having circular apertures 4-2 and 43 therein concentric with the shaft 15. A bearing support 44 is bolted or otherwise secured in one such aperture 43, this bearing support including a peripheral flange 45 anda cup-shaped closure 46 integral therewith and designed to enclose an end of the shaft 15. A bearing 47 is supported by the bearing support 44 and encircles the small diameter end portion 49 of the impeller shaft 15 to form a bearing therefor. It should be noted that the bearing support 44 may fit either in the aperture 43 at one end of the housing or the aperture 42 at the opposite end thereof. housing, which will be later described, may be located on either side of the pump housing. v

` A passage 48 extends through a portion of the volute cover 14 into the volute chamber at 'a point'subject to iluid pressure from the volute. This passage communicates with an angular passage 49 extending through the cover 14 to communicate with the stuing box 30 in the area of the lantern ring 33. The passage 48 is also connected by suitable fittings 50 and 51 connected by` a conduitV 52 to a passage 53 through the volute cover 1 4 to communicate with the stuffing box 32 in the area ofv the lantern ring 34. The purpose'of this arrangement will be evident when it is understood that the impeller 21 is the first stage.

impeller and discharge pressure therefrom maycornmunicate with the stuing box 30 to deliver water-there- 30 from outer atmosphere and the passagesmentioned permit liquid under pressure to act as a sealing lubricant.

This arrangement is made so that the transmission the conduit 52 and the passage 53, act to similarly lubricate the stuffing box 32 when the impeller discharges are connected in parallel. When the impellers are connected in series, the pressure in the area of the lantern ring balances with pressure in the intake manifold 12.

The transmission housing is best shown in Figure 1 of the drawings. It includes a hollow body portion which is elongated in a vertical direction and includes means for supporting three shafts in parallel relation. The lirst shaft comprises the projecting end of the impeller shaft 15. An idler shaft 54 is supported in parallel relation to the impeller shaft 15. A drive shaft 55 and an aligned driven shaft 56 are supported in parallel relation to the first mentioned shafts.

A bearing support 57 encircles the projecting end of the impeller shaft and supports a pair of spaced bearings 59 and 60 having a pinion 61 secured on the shaft 15 therebetween. The end of the bearing support 57 ex tends into the aperture 42 in the outboard support 40. This bearing support 57 fits between the body portion 62 of the transmission housing and the removable top portion 63 thereof. This top portion 63 is connected to the body portion 62 of the housing along a horizontal parting line on a plane through the axis of the shaft 15.

Aligned apertures 64 and 65 are provided in the gear housing 62 for accommodation of bearings 66 and 67 encircling the idler shaft 54. Cover plates 69 and 70 overlie the apertures 64 and 65 to close the ends thereof. A closure plate 71 also closes the outer side of the bearing support 57 and a seal 72 encircles the shaft 15 inwardly of the bearing 59 to form a closure for the portion of the gear housing through which the shaft 15 extends.

An idler gear 73 is mounted upon the shaft 54 to mesh with the pinion 61 and also with the gear 74. This gear 74 is mounted upon a sleeve or hub 75 rotatably supported for pivotal movement about the drive shaft 55. Bearings 76 are interposed between the drive shaft 55 and the hub 75 so that the two parts may be freely rotatable.

The drive shaft 55 extends through an aperture 77 in a closure plate 79 secured to close the opening S0 in one side of the transmission housing. A bearing 81 is supported by the closure 79 to support one end of the shaft 55. A closure plate 82 is designed to close an opening 83 in the housing 62 opposite the aperture 80. The closure plate 82 includes a cup-shaped projection 84 which supports spaced bearings 85 which rotatably support the shaft 56. The shaft 56 extends through an aperture 86 and a seal 87 is provided for closing the housing at this point.

The end of the shaft 56 is provided with -a peripheral ange 89 connecting the shaft with an externally splined sleeve 90. The shaft 55 is provided with a splined or toothed end 91 of the same diameter as the sleeve 90. The hub 75 is likewise toothed or splined at 92. An internally splined sleeve 93 is slidable over the gear or splined part 91 and is selectively engageable with either the sleeve 90 or the end 92 of hub 75. As a result when the sleeve 93 is in the position shown in Figure 1, the drive gear 55 is rotatably connected to the driven shaft 56. When this sleeve 93 is moved to the left from the position shown, it may rotatably connect the members 91 and 92 to rotate the hub 75 in unison with the drive shaft 55. Rotation of the gear 74 on the hub 75 acts through the idler gear 73 and the pinion 61 to rotate the impeller shaft 15. axial alignment, the reduced diameter end 94 of the drive shaft 55 is supported by a bearing 95 within the externally splined sleeve 90.

From an examination of Figures 1, 2 and 3 of the drawings it will be noted that the hub 75 also supports a gear 96 for rotation therewith. This gear 96 meshes with a gear 97 mounted upon a shaft 99 which is laterally spaced from the gear 96. The transmission housing 62 is provided with an opening 100 therein which is To hold the shaft 55 and 56 in.

normally closed by a closure plate 101 forming the mounting plate of a priming pump housing 102. The priming pump housing includes a pair of spaced

plates

103 and 104 which are connected by a pump chamber forming ring 105. The

plates

103 and 104 are provided with

opposed bosses

106 and 107 designed to accommodate bearing sleeves 109 `and 110 to support a pump rotor shaft 111. A pump rotor 112 on the shaft 111 is in mesh with a cooperable rotor 113 on a parallel shaft which is an extension of the shaft 99. This shaft 99 is supported by a bearing sleeve 114 in a boss 115 in the plate 104 4and asimilar sleeve .116 in the mounting plate 101.

The shaft 99 is provided with a reduced diameter end 117 extending through a bearing 119 inwardly of the gear 97. Alternate clutch plates of the disc clutch 120 are connected to a hub 121 on the gear 97 and the remaining plates are connected to the shaft 99. A sleeve 122 having a peripheral groove 123 therein is provided to apply pressure against the plates 120 to cause the shaft 99 to rotate in unison with the gear 97 when it is so desired.

As is indicated in Figure 3 of the drawings, a shifting fork 124 is pivoted at 125 to a fixed support 126 and includes rollers 127 engageable in the groove 123 of the sleeve 122. The end of the shifting fork opposite the pivotal connection is pivoted at 129 to an operating rod 130 which extends through an aperture 134 in the plate 101. The clutch 120 is normally held in disengaged position by a spring encircling the operating rod 130.

With reference now to Figure 5 of the drawings, it will be noted that the body of the pump is provided at opposite ends with attachment anges 143 and 144 which define the ends of the intake manifold passages 11 and 12 as well as the discharge passage 13. Generally Y- shaped sections and 145 are connected to the ends of the pump body, ange 146 of each section being bolted or otherwise secured against anges 143 and 144. Each of the Y-shaped

sections

145 and 145 is designed to connect the ends of the intake passages 11 and 12 to a common passage. Each of the castings 145 `and 145' is pro vided with an end ange 147 which is bolted or otherwise -afxed to a corresponding flange 149 of an end section 150 of the intake housing. The outer extremities of the sections 150 are threaded at 151 for connection with a conduit leading to the supply source. shown closing each end of the intake manifold structure, it being understood that one such cap is removed for connection with the suction conduit.

The anges 143 and 144 are also bolted or otherwise connected to discharge manifold castings 153 and 153', respectively. The discharge manifold 153 is of Y-shape with each passage end being flanged as indicated at 154. Discharge valves 155 Iare bolted or otherwise connected to the anges 154, these valves being provided with operating handles 156 by means of which the valves may be individually operated.

Figure 6 is a ow diagram showing the manner in which the pump may operate with the impellers either in series or in parallel. When the pump is to operate with the volutes in parallel, the fluid enters the intake manifold structure and flows through the manifolds 11 and 12 to the intake of the volutes. The rst stage impeller 21 directs the ow through the volute 16 to a transverse passage 162 which leads to the transfer valve 163. With the transfer valve in the position shown in Figure 6, the discharge from the transfer valve is conducted to a passage 164 leading to the discharge manifold 13. From the manifold 13 the fluid may ow in either direction through the desired casting or castings 153 aud 153' as previously described.

The discharge from the second stage impeller 22 ows through a passage 165.to a transverse passage 166 communicating with the discharge manifold 13. In this arrangement the suction side of both impellers are in com- A cap 152 is.

munication with the water supply source through the manifolds 11 and 12.

When the pump is in series, the transfer valve 163 is turned to its second extreme position. In this position the fluid enters the manifold 11 and passes into the impeller 21. The fluid flows through the volute 16 and into the transverse passage 162. The fluid ows through the transfer valve 163 and into the intake manifold 12 leading to the seco-nd stage impeller 22. This causes an increase in pressure in the manifold 12 and in the adjoining intake passages 167 and 169 in the Y-shaped

castings

145 and 145. This unbalanced pressure causes the flap valves or

check valves

170 and 171 to swing into closed position so that the discharge from the iirst im-v peller 21 flows into the intake of the second impeller 22. The discharge from the second impeller passes through the passage 165 to the transverse passage 166 communicating with the discharge manifold 13.

In Figure 5 of the drawings is disclosed diagrammatically an actuating device 201 which is used to operate the transfer valve. The transfer valve is provided with an operating shaft 202 which projects from the pump housing and is provided with an operating lever 203 by means of which the transfer valve may be rotated. The device 201 comprises an expandable and contractable element which is pivotally connected at 204 to the pump housing and pivotally connected at 205 to the transfer valve lever arm 203. Upon expansion of the device 201 or elongation thereof, the transfer valve is operated in a counterclockwise direction to its other extreme position. The device may operate in both directions or is reversible.

Figure 4 of the drawings diagrammatically illustrates the operation of this apparatus. This ligure illustrates the Vacuum actuated device 201 which is shown as including a cylinder 206 having a piston 207 therein which is reciprocable between two extreme positions. A conduit 209 connects the valve element of the device 201 through a check valve 210 with the intake side of the priming pump 102. Thus, under certain conditions when the priming pump 102 is in operation, a source of partial vacuum is provided.

As is indicated in Figure 2 of the drawings, the priming pump closure plate 104 may include as an extension of the boss 107 a mounting ange 211 to which may be secured an electric motor 212. rl'he shaft 208 may be coupled to the rotor shaft 111 by a suitable coupling member 218. This motor 212 may be operated to actuate the priming pump when desired so that this pump may be selectively operated either electrically or mechanically through the gear train and transmission. Y

The intake of the priming pump 102 is connected by a portion of the conduit 209 and a connecting conduit 213 to a priming valve 214. This priming valve 214 includes a connection 215 communicating with the centrifugal pump discharge. It also includes connections 216 leading to the suction eyes of the first and second stage of the centrifugal pump. The valve 214 is actuated by a solenoid 217 which is arranged in a circuit which will be later described.

When the pump is to be primed, air is drawn from the suction eyes of the impellers through the passages 216, the valve 214 and the

conduits

213 and 209 to the intake of the priming pump 102. The discharge of the priming pump is indicated at 219 and leads to atmosphere. The valve 214, is operated by an internal spring to close the outlet conduit 213 and inlet conduits 215 and 216 by releasing push button switch 229. Thus when the pump is primed, the Valve 214 is closed to prevent uid under pressure from bypassing to the suction eyes and leaking out to atmosphere through priming pump 102. The check valve 210 permits air to be drawn from the valve 220 of the device 201 to the priming pump but will not permit a Vreverse flow.

When it is desired to prime the pump through the use of the priming motor 212, the switch 229 is closed. One

terminal 189 of the vehicle battery 187 is grounded, while the other terminal 190 is connected through the ignition switch 191 to the circuit breaker 192. A connection 221 leads from the battery terminal 190 to a relay contact 222 which is normally in spaced relation to a cooperable contact 223. The contact 223 is connected by a con.

ductor 224 to one terminal of the priming pump motor 212. The other terminal of this motor is grounded as indicated at 225.

The relay coil 231 is connected by a conductor 226 to one terminal 227 of a double pole singlerthrow switch 229. When this switch is closed a circuit is closed to conductor 230 leading to the circuit breaker 192. Thus when the switch 229 is closed a circuit is closed from the battery terminal 190 through the circuitbreaker 192, conductor 230, terminal 227, conductor 226, to one terminal of a relay coil 231 which controls the movement of the armature 232 supporting contact 223. The other terminal of the coil 231 is grounded at 233. As a result, current will ow from the battery terminal 190 through conductor 221, contacts 222 and 223, and conductor 224 to the motor to energize this motor. The switch 229 is provided with a grounded terminal 234 connected to a switch arm engageable with a contact 235. This contact is connected to one terminal of a relay coil 236 to ground thisrside of the coil when the switch 229 is closed. The other relay coil terminal is connected by a conductor 237 to the conductor 230 leading to the ungrounded side of the battery; thus completing the circuit and energizing the coil 236.

The coil 236 attracts an armature 228, which draws contact 238 into engagement with contact 239 connected by

conductors

237 and 230 to the ungrounded side of the battery. The contact 238 is connected by conductor 240 to the solenoid 217, the second terminal of which is grounded at 241. Thus, when switch 229 is actuated to operate the priming pump motor 212, the solenoid 217 is also actuated to operate the valve 214. As a result, the inlet 209 of the priming pump 102 is connected by

conduits

213, 215 and 216 to the interior of the centrifugal pump acting to evacuate air therefrom and to draw water from a suitable source into the pump intake.

The transfer Valve operating mechanism lis indicated in Figure 4 of the drawings and includes a double pole double throw switch 242 with momentary contact positions and a center off position. The switch arms of the switch 242 are electrically connected by conductor 243 with the conductor 230 leading to the ungrounded side of the battery 187. Accordingly, when the transfer valve is operated (normally at a time when the pump is in operation) one of the switch blades is in contact either with the switch terminal 244 or the switch terminal 245, both of which are connected by the conductor 246 to the conductor 226 which energizes the relay coil 231 yand starts the priming` pump in operation. The other blade of the switch 242 is selectively connected to a switch contact 247 or a contact 249. Contact 247 is connected by a conductor 250 to the common terminal 251 of aA switch 252. The switch contact 249 is connected by a conductor 253 to the common terminal 254 of a switch 255. These switches 252 and 255 are of the single pole double throw type including one normally open terminal and one normally closed terminal.

The normally closed terminal 256 of switch 252 is connected by conductor 257 to one terminal of a solenoid 220 which is double acting and which is grounded at 259. The normally closed terminal 260 of switch 255 is connected by a conductor 261 to the opposed coil of the solenoid 220. When one of the normally closed switches is closed the solenoid valve moves in a direction to allow air from one side of piston 207 in cylinder 201 to ow to the priming pump, and air from the atmosphere to flow to the other side of the piston, so that the piston will move and actuate the transfer valve in a corresponding direction. When the other normally closed 7 switch is closed, the air tlow is reversed so that the transfer valve will be operated in the opposite direction.

The normally open terminal 262 of switch 252 is connected by a conductor 263 to one terminal of an indicating light 264, the other terminal of which is grounded at 265. Similarly, the normally open terminal 266 of switch 255 is connected by a conductor 267 to a second signal light 269, the other terminal of which is grounded at 265.

As is evident in Figure 4, the switches 252 and 255 are actuated by the valve arm 203 which controls the transfer valve. When the valve arm 203 is in the position shown in full lines, the common terminal 251 will be connected to terminal 262 connected by conductor 263 to the indicating light 264 which is illuminated to indicate that the transfer valve is in position for parallel operation. At this time switch 255 is not in circuit, the switch 242 being in position for parallel operation. When it is desired to change the transfer valve, to operate with the volutes in series, the switch 242 is moved into a position where the contacts 245 and 249 are connected to the ungrounded side of the battery. As a result, a circuit is again closed through terminal 245 and conductors 246 and 226 to actuate the relay coil 231 starting the priming pump in operation. At the same time a circuit is closed from the ungrounded side of the battery through terminal 249 and conductor 253 to the common terminal 254 of switch 255. This switch closes a circuit from terminal 260 through conductor 261 to the solenoid device 220; thus moving the valve in the opposite direction and permitting the air from the atmos` phere to flow to the left side of the piston and air from the right hand side of the piston to flow to the priming pump. This action moves the piston 207 to the right until the arm 203 engages the operating button 270 of switch 255, breaking the circuit to the solenoid valve 220 and closing the circuit through terminal 266 to the conductor 267 acting to illuminate the indicating light 259 to Show that the transfer valve is in position for series operation. 'Ihe switch 242 is then opened until further operation is required.

In transferring the pump to parallel operation, the switch 242 is moved to its left hand position operating to actuate the solenoid valve 220 in a manner to allow atmospheric air to ow to the right hand end of cylinder 201 and to evacuate air from the left hand end of cylinder 201, moving the piston 207 to the left until it reaches its opposite extreme position.

In accordance with the patent statutes, we have described the principles of construction and operation of our improvement in centrifugal pump and priming pump assembly, and while we have endeavored to set forth the best embodiment thereof, we desire to have it understood that changes may be made within the scope of the following claims without departing from the spirit of our invention.

We claim:

1. A control apparatus for a series parallel pump having a pair of impellers, transfer valve means movable between two positions for connecting said impellers in series or in parallel, and a priming pump for evacuating the centrifugal pump and priming the same, the control apparatus including a vacuum actuated means connected to said transfer valve for actuating the same between said two positions, and conduit means connecting said vacuum actuated means to the intake of said priming pump, said priming pump when operated providing a source of partial vacuum for actuating said vacuum actuated means, drive means for driving said impellers, and clutch means selectively connecting said drive means to said priming pump for actuating the same.

2. A control apparatus for a series parallel pump having a pair of impellers, transfer valve means movable between two positions for connecting said impellers in series or in parallel, and a priming pump for evacuating the centrifugal pump and priming the same, the control apparatus including an expandable and contactable vacuum actuated means connected to said transfer valve for moving the same between said two positions, conduit means connecting said vacuum actuated means to the intake of said priming pump, said priming pump when actuated providing a source of partial vacuum for actuating said vacuum actuated means, and drive means for actuating said priming pump.

3. A control apparatus for a series parallel pump having a pair of impellers, transfer valve means movable between two positions for connecting said impellers in series or in parallel, and a priming pump for evacuating the centrifugal pump and priming the same, the control apparatus including a cylinder, a piston slidably supported in said cylinder, means connecting said cylinder and piston between said transfer valve and a fixed pivot to actuate said transfer valve between said two positions, a conduit connected to the intake of said priming pump, a pair of connections to opposite ends of said cylinder, valve -means interposed between said conduit and said connections to selectively connect said conduit with either of said connections, said priming pump, when actuated, providing a source of partial vacuum to said vacuum actuated means, and drive means for actuating said priming pump.

References Cited in the le of this patent UNITED STATES PATENTS 2,660,956 Waterous Dec. l, 1953 2,683,420 Hill et al. July 13, 1954 2,701,530 Schellerer Feb. 8, 1955 2,780,998 Cilker Feb. 12, 1957 2,790,393 Thomas et al. Apr. 30, 1957 2,799,466 Hickerson July 16, 1957 2,863,628 Rimsha et al Dec. 9, 1958