US2112651A

US2112651A - Centrifugal pump

Info

Publication number: US2112651A
Application number: US41280A
Authority: US
Inventors: Charles H Fox
Original assignee: Ahrens Fox Fire Engine Co
Current assignee: Ahrens Fox Fire Engine Co
Priority date: 1935-09-19
Filing date: 1935-09-19
Publication date: 1938-03-29
Anticipated expiration: 1955-03-29

Description

March 29, 1938. c ox 2,112,651

CENTRIFUGAL PUMP Filed Sept. 19, 1935 8 Sheets-Sheet l nfnvawfirv 7 CHARLES H. Fox, =1

-March 29, 1938. Q H, FOX 2,112,651

CENTR IFUGAL PUMP Filed Sept. 19, 1935 8 Sheets-Sheet 2 IIIIIIIIL 'IIIIIIIZ 'IIIII March 29, 1938. c. H. FOX

CENTRIFUGAL PUMP Filed Sept. 19, 1935 8 Sheets-Sheet 3 J'mv wo'b CHARLES H. FOX,

Mani-h 29, 1938.

C. H. FOX

CENTRIFUGAL 'PUMP Filed' Se pt 19, 1955 8 Sheets-Sheet 4 March 29, 1938.

c. H. FOX

CENTRIFUGAL PUMP Filed Sept. 19, 1935 8 Sheets-Sheet 6 1 Jweww f" CHARLES ".FOX,

Guam

March 29, 1938. c. H.FO X 2,112,651

CENTRIFUGAL PUMP Filed Sept. 19, 1935 s Sheets-Sheet '7 March 29, 1938.

C. H. FOX

CENTRIFUGAL- PUMP Filed Sept'. 19. 1935 8 Sheets-Sheet 8 FIG. 1 2.

Fifi/3.

Patented Mar. 29, 1938 I v UNITED STATES PATENT OFFICE CENTBIIFUGAL rum Charles H. Fox, Cincinnati, Ohio, assignmto The Ahrens-Fox Fire Engine Company, Cincinnati, Ohio, a corporation of Ohio Application September 19, 1935, Serial No. 41,280

4 Claims. (Cl. 16924) This invention relates to fire engines, and in through one of the pumps shown in Figure 1, particular, to power-operated pumping engines and taken along the line 1-1 of Figure 1. wherein the pumping units consist of centrifugal Figure 8 is a fragmentary side elevation of pumps. the right-hand side of the mechanism shown in One object of this invention is to provide a fire Figure 1.

engine pumping unit composed of a pair of cen- Figure 9 is a fragmentary plan view of aportrifugal pumps operated by independent driving tion of the mechanism shown in Figure 1, illustra'nsmissions, but having their intakes and outtrating the manner of operating the diversion lets connected to a common source and a comvalve.

10 mon exhaust, respectively, the pumps being ca- Figure '10 is a side elevation of a fire engine. 10 pable of operation either individually or comwith the body and super-structuresuperimposed bined in series or in parallel. upon the chassis shown in Figure 1, illustrating Another object is to provide a pumping unit the positions of the various elements of the inof the type previously set forth, wherein each vention. pump consists of a centrifugal pump comprising Figure 11 is an end elevation of the auxiliary 15 one or more stages. I pump employed in the fire engine of this inven- Another object is to provide a fire engine tion.

pumping unit consisting of a pair of centrifugal Figure 12 is a top plan view of the auxiliary pumps, a power plant, independent transmispump shown in Figure 11.

., sions' for driving each pump from the power Figure 13 is a transverse section through the plant, the pumps being capable of being driven common intake conduit and the main suction either individually or together, the transmissions chamber, taken along the line l3--l3 of Figure 6. being arranged so that the pumps may be start- Figure 14 is a diagrammatic view of the several ed selectively. parts of the apparatus.

Another object is to provide a pumping unit One of the problems hitherto encountered in mp d f a p ir of c ntrifugal pumps in a the manufacture of fire-fighting equipment was hydraulic C u e intakes of t P p being to provide a fire engine which would be capable adapted to communicate with a source of supof emeiently handling the varying requirements P y, a t a Valve means being a a ed to of service. A fire in a high building requires the :0 cut off one of the intakes from such a source pumping of water at high pressure. On the when the outlet of the other pump is connected other hand, a large fire in a low building rein series with its intake, so as to operate the quires th application of th m ximum quantity wo p p in series o pr vi a m ximum presof water without the necessity for high pressure delivery. 7 sures. Furthermore, the majority of fires en- 5 In the'draw n sl countered and which the fire engine is expected Figure 1 P View Of the chassis t to extinguish, are of a very small nature, in low fire engine of this invention, with the various buildings or in it ti umn th ap licaunits'mounted thereon but with h o y and tion of small quantities of fluid at low pressures. perstructure removed in order to more clearly Amodem fire gi h r, i ordertomeet 40 dis se the Various mechanismsthe requirements of the underwriters, must be 40 gure 2 s an irregular Cross ct o through designed to accommodate the maximum delivery the Pumping unit of Figure taken DP and the maximum pressure specified by the regumfltely ong the line 2-2 thereof. lations. To accomplish this the present, in-

Figure 3 is an enlarged fragmentary view of 'ventor has found that centrifugal pumps are the diversion valve shown inv combination with suitable for pumping fluid to extinguish large or 45 other elements in Figure 2, the valve being set high fires. A centrifugal pump, however, is

to connect the two pumps in series. somewhat inflexible in that it has an unavoidably Figure 4 is a view similar to Figure 3, but with narrow range within which it operates emciently. the valve set to connect the two pumps in par- The centrifugal pump cannot be slowed down 4 allel. v in proportion to a requirement for smaller 50 Figure 5 is an end view of the pumping unit amounts of water, but must be kept up to speeds shown in Figure 1. compatible with certain pressure requirements. Figure 6 is a horizontal section taken along Furthermore, the present inventorhasfound that the line 6-6 of Figure 5. small Jets of water are more satisfactory for ex- Figure '7 is a longitudinal," vertical section tinguishing small fires than the jets of chemicals 56 previously employed. To reconcile all of these varying requirements encountered in fire-fighting was the problem of the present inventor.

To solve this problem the present inventor has provided a fire engine having a pair of centrifugal pumps, together with a small auxiliary pump. These pumps are provided with transmissions and power takeofls of such a nature that either of the main pumps may be operated individually in order to most efliciently extinguish a fire of medium size. Both of the main pumps may also be operated simultaneously, either in series .where high pressures are more important than great volume, or else in parallel where a large volume delivery is more important than a high pressure. The small auxiliary pump is arranged to serve as an exhauster for either of themain pumps, or else as an additional pump for pumping small quantities of fluid either from a tank carried by the fire engine or from an independent source of supply, this being used for very small flres where it would be inefficient or costly to operate either of the main pumps.

Referring to the drawings in detail, Figure 1 shows the central portion of the fire engine of this invention in plan view with the body and other super-structure removed. In this figure it will be seen that the flre engine has a frame with side members I, upon which is mounted the motor, generally designated 2, having a flywheel housing 3 with side extensions joined to the frame, as at 4. The Junctions 4 provide the required points of support of the motor 2. To the rearward side'of the flywheel housing 3 is joined a clutch housing 5, which incloses a driving clutch (not shown), whereby the two may be connected to the remainder of the mechanism. This clutch is of a conventional type, and its details together with the details of the engine, form no part of the present invention.

Mounted rearwardly of the clutch housing 5 is the main transmission unit 6, consisting of a standard selective type gear box having the usual arrangement of gears to provide the speeds forward and reverse required for propelling the ordinary vehicle. The main transmission unit 6 is operated by a hand lever 1 in the usual manner, and serves to impart power to a pump drive unit 3 attached to and connected with the main transmission unit 6. The power from the latter is applied in a manner subsequently to be described, either to the propulsion of the vehicle by way of the traction drive shaft 9, or else to the pumps, either individually or in combination through the right-hand pump driving connection M, or through the left-hand pump driving connection The universal joints l2 and I3 serve as usual to transmit the power through the traction drive shaft 9, under varying angles, to the rear axle of the truck. The disc-type parking brake |4 serves the usual purpose of locking the main traction drive shaft 9.

The pump driving connections l8 and II are joined respectively to a pair of main pumps, the right-hand main pump being generally designated l5 and the left-hand main pump l6. Each of these pumps is substantially identical with the other, and a description of one will suflice.' The details of these main pumps are shown inv Figure 'I and will be described later. The left-hand main pump I6 is connected to'a common intake conduit -|1 (Figure 5), which terminates on opposite sides of the frame in the intake ports l9. The intake conduit I1 is secured to the frame members by means of the brackets |9. The right-hand main pump l5 (Figure 5) isprovided with an intake conduit 29 (Figures 2 and 5), connected as at 2| to the common suction chamber 48, as will appear later. The intake conduit 20 leads into the casing of the pump l5, as will subsequently appear. The fluid pumped by the first stage of the pump is discharged into the first-stage volute 22, and thence into the cross-over conduit 23, which connects the outlet of the first-stage volute, as at 24, with the inlet 25 (Figure 2) of the second-stage, as at 26.

This fluid is pumped by the second stage of the pump l5 into the second-stage volute 21, the latter being joined, as at 28, to the discharge leader 29. The latter is connected, as at 30, with the common discharge header 3|. Attached to the common discharge header are hose gates 32, which varyin number according to the pumping capacity desired. These hose gates 32 are operated by the handles 33 in order to control the flow of fluid into the various lines of hose connected to these hose gates.

The intake 34013 the left-hand main pump I6 is similarly connected, as at 35, to the intake conduit I1, and the fluid pumped by its first stage passes into its first-stage volute 36. The latter is connected, as at 31, to the cross-over 38, this being, in turn, connected, as at 39, to the second stage of the pump IS. The fluid delivered by this second stage passes into the second-stage volute 48, which is connected, as at 4|, to the diversion valve casing 42, consisting of a projecting portion of the common discharge header 3| The diversion valve casing 42 contains the diversion valve member 43 (Figures 2, 3 and 4), having a passageway 44 therethrough. When the valve member 43 is set, in the manner shown in Figures 2 and 3, the discharge of fluid from the left-hand pump volute 48 passes through the valve into the series branch conduit, generally.

designated 45. The latter consists of the conduit sections 46 and 41, joined to one another at the junction 49 (Figure 2). The series branch conduit 45 is joined at one end, as at 50, to the diversion valve casing 42. At its opposite end it is joined to the main suction chamber 48 (Figure 6). The main suction chamber 48 terminates in the automatic valve chamber 52. The automatic valve chamber 52 contains the automatic valve member 53, serving to close the port 54 leading therefrom into the common intake conduit l1. The automatic valve member 53 is pivoted at 55 to an arm 55, which in turn, is pivoted around the shaft 51 and impelled into a position closing the port 54 under the urge of the spring 58. The intake conduit 20 of the right-hand main pump l5, as previously stated, is connected to the automatic valve chamber 52 at the junction 2| (Figure 13) The diversion valve member 43 (Figure 2) is rotatably mounted in its casing 42 upon the shaft 59, this shaft carrying at its outer end the skew gear 68. The latter meshes with a pinion 6| mounted upon the shaft 62 and journaledin bearings 63. The opposite end of the shaft 62 is provided with a hand wheel 64. By manually rotating the hand wheel 54 the position of diversion valve member 43 may be varied to connect the the right-hand pump driving connection I8 from the pump drive unit 8 (Figure 1). The left-hand main pump I6 is similarly driven independently from the left-hand pump driving'connection II, also connected to the pump drive unit 8. The pump drive unit 8 ,contains sliding gears which are movable in a conventional manner to connect the main transmission unit 6 with either or both of the pump driving connections I8 and II.

The gear shifting for this purpose is accomplished by rotating the shaft 65 through the agency of the hand lever 66 mounted thereon. The hand lever 66 engages a quadrant 61 having five notches 68, 69, I8, II and I2 therein (Figure 8). By shifting the lever 66 into one of these fivenotches, as will be explained later, the power from the engine may be connected selectively to the chassis drive shaft 9, to the right-hand pump I5, to the left-hand pump I6, or in a neutral position. The gears in the pump drive unit 8 are prevented from clashing during this shifting by the operation of a vacuum-actuated device 13, which disconnects the clutch within the clutch housing 5 through the connecting arm I4 (Figure 1) whenever the lever 66 is shifted to a new position.

The main clutch may be released manually by the operator by means of pressure applied to the clutch pedal I5 (Figure 1). The brakes of the fire engine are applied by pressure upon the brake pedal 16, assisted by the master brake cylinder 11 and the master brake vacuum cylinder I8. The parking brake I4 is applied by operating the hand brake lever 19, (Figure l) in the ordinary manner. The details of the braking and clutch system, as described above, form no part of the present invention.

. An auxiliary pump 88 of the positive displacement type (Figure 1) is driven from the shaft 8i emerging from the auxiliary pump power takeoff 82, the latter being connected to the main transmission 6. The auxiliary power pump takeoff 82, of a conventional type the details of which form no part of the present invention, is operated to connect or disconnect the auxiliary pump 88 from the source of power by shifting the auxiliary pump hand lever 83 (Figure 1). The latter is mounted upon the shaft 84, which is journaled in the casing of the pump drive unit 8 and carries at its opposite end an arm 85. The latter is connected by the connecting rod 86 to an arm 81, mounted upon the auxiliary pump control shaft 88. The latter serves to operate clutch means within the auxiliary pump power take-off 82 to connect or disconnect the auxiliary pump 88 from the power source.

The auxiliary pump 88 (Figures 11 and 12) is of a conventional type, the details of which form no part of the present invention. This pump comprises a casing 89 having end plates 98 and 9| secured thereto as by the 'cap screws 92. The upper side of the casing 89 is provided with a junction 93 arranged for connecting the auxiliary pump intake pipe 94 thereto. The opposite or bottom side of the auxiliary pump 88 contains a similar junction 95, to which is connected the auxiliary pump outlet pipe 86.

The auxiliary pump intake pipe 94 leads to the three-way valve 91, having an operating handle 98 (Figure 14). From one of the three connections on the opposite side of this valve the pipe 99 leads to the tank I88. This tank is arranged to containwater, somewhat over one hundred gallons in quantity. The middle connection of the three-way valve 91 is connected to the pipe main pumps I5 and I6, thereby setting up the initial draft necessary to cause these pumps to operate or finally to draw in water from the hose connected to the hose connection I83, this hose being connected to a hydrant, pond or other external source of supply. The outlet pipe 96 of the auxiliary pump 88 leads to the hose connection I84. The latter serves for the connection of a small hose which may be used for extinguishing small fires, the fluid being supplied by the pump 88.

. The main driving pumps I5 and I6 are of the two-stage centrifugal type shown in longitudinal section in Figure 7. The details of these pumps in themselves form no part of the present invention, hence, a brief description will suffice. The right-hand main pump I5 is chosen for purposes of description, although it will be understood that the left-hand main pump I6 might be similarly described.

As previously described, the main pump I5 is provided with an intake conduit 28, leading to the casing I 85 (Figure '7). The latter is provided with a pair of interior chambers, namely, the first-stage chamber I86 and the second-stage chamber'lnl. Surrounding these chambers I86 and I8! is a water jacket chamber I88. The chamber I 88 is connected to the radiator or cooling system of the motor 2 so that the fluid passing through the pump is utilized to assist the cooling system of the motor in warm weather, and the warm water from the radiator is utilized to keep the pumps from freezing in cold weather. The details of this cooling and warming system form no part of the present invention, but are contained in my copending application, Ser. No. 27,404, filed June 19, 1935.

The pump casing I85 is provided with end plates I89 and H8, each of these having bores I I I and I I2, respectively, serving to receive packings H3 and H4, surrounding sleeves H5 and 'I I6, respectively. Passing through these sleeves is the pump drive shaft 1 having the end portions H8 and H9 thereof rotatably supported by the anti-friction bearings I28 and I2I, respectively. The driving end adjacent the bearing I28 is provided with a universal or self-aligning connection, generally designated I22, which serves to compensate for slight changes in alignment or slight errors in assembly. The packings H3 and x II4 may be compressed to prevent leakage by turning the glands I23 and I24, respectively, these being locked in their adjusted positions by the latch members I25 and I26, operating in the notches I21 and I28.

The drive shaft III is provided with a pair of splined portions I29 and I88, (Figure '7) upon volute 22. This volute is connected at the'junction 24 to the cross-over 23, which leads to the second-stage volute 21 in the manner previously described. v

The second-stage rotor I33 is similar in form to the first-stage rotor I3I but is secured to the splined portion I29. Its outwardly directed passages I34 are curved in a direction away from the passages I32 so that the thrusts thereof tend to react upon one another and compensate for end thrust. The outer ends of the second-stage rotor passages I34 open into the chamber. within the second-stage volute 21. The latter is con nected at the junction 28 to the discharge leader 28 (Figure 1) and this, in turn, is connected to the distribution header 3| in the manner previously described.

The pump drive shaft II'I receives power from the pump driving connection III, through the tubular drive shaft I35 thereof by way of the universal joint I 22.. The rotation of the first and second-stage rotors I3I and I33, respectively, causes the fluid to be thrown outwardly into the first and second-

stage volutes

22 and 21, the fluid passing onward under pressure thus created.

The traction drive shaft 8 receives bearing support through the agency of a bearing assembly I48, supported by the intake header I I by means of the right-angled bracket I 4| secured thereto (Figures 1, and 8). In this way the intake header I'I serves to support not only one of the pumps, but also the drive shaft 9. v

In the operation of the valve mechanism, to connect the main pumps I5 and I6 in series so that the maximum pressure will be obtained,,the diversion valve member 43 is rotated by the hand wheel 64 into the position shown in Figures 2 and 3. In this position the fluid is drawn into the left-hand main pump I6 through its intake conduit 34 from the common intake conduit IT. This fluid is placed under pressure by the pump and is discharged from the second-stage volute thereof into the diversion valve chamber 42 (Figure 2). The fluid passes .through the diversion valve passage 44, the series branch conduit 45 and the automatic valve chamber 52, upwardly into the intake conduit .20 of the right-hand main pump I5 (Figures 6 and 13). The fluid, which is already under pressure from the left-hand main pump I6, is furthersubjected to pressure in the right-hand main pump I5, and passes outwardly therefrom through the discharge leader 29 into the distributing header 3I. The fluid is distributed from the distributing header 3|, through the hose gates 32, into the various lines of hose by turning the valve handles 33 in a conventional manner:

'Io connect the main pumps I5 and I6 in parallel, whereby to obtain the maximum volume of delivery of fluid, the hand wheel 64 is rotated so that the diversion valve member 43 is set in the position shown in Figure 4, thereby cutting off the series branch conduit 45 from communication with the left-hand main pump I6 (Figures 2 and 4) of the pumps I5 and I6 take in fluid independently. The right-hand main pump I5 draws in fluid through its intake conduit 28 from the automatic valve chamber 52, the automatic valve member 53'opening inwardly (Figure 6) against the urge of its spring 58, to permit fluid tapes from the common intake conduit II through the port 54. At the same time the left-hand main pump' I6 draws in .gfluid from the same intake conduit I] through its intake conduit 34.

Each of the pumps I5 and I6 places 'the separate quantities of fluid under pressure and discharges these, each through its ownvolute. The right-hand main pump. I5 discharges its, fluid With the.valve set in this position both I from its second-stage volute 21, through the discharge leader 29 into the distributing header 3| (Figure 1). At the same time the left-hand main pump I6 discharges its fluid from'its sec ond-stage volute 40 through the diversion valve passage 44, set in the position shown in Figure 4, into the distributing header 3|. The separately pumped quantities of fluid thus unite in the distributing header 3| and are distributed to the various hose lines by way of the hose gates 32. Thus by suitable manipulation of the hand wheel 64 the diversion valve member 43 may be rotated to place the main pumps I5 and I6 in series to produce the maximum pressure at a sacrifice in volume, or to produce the maximum volume delivery at the sacrifice of pressure. This alteration may be made in accordance with the conditions encountered in the particular fire.

It will thus be seen that the pump drive unit 8 and the pump driving connections II) and II are arranged in such a manner that the shifting of the hand lever 66 causes both pumps to be operated, either individually or collectively. The pump drive unit 8, however, is so arranged as to prevent the simultaneous starting of both of the main pumps I5 and I6, and to permit these pumps to be started only in succession to one another.

In the operation of the mechanical driving connections of the main pumps I5 and I6, when the lever 66 is shifted into the first notch 68 (Figure 8), power from the main transmission 6 is transmitted through the traction drive shaft 9 and the universal joints I2 and I3 to the rear axle of the truck, thereby propelling the truck. With the lever 66 in the second notch 69 the drive connection is broken between the traction drive shaft 9 and the main transmission 6, thereby nullifying the transmission of power for the purpose of propelling the truck, yet permitting the transmission of power to the pump driving units.

With the lever 66 in the third notch III the pump driving connection III is operatively connected to the main transmission 6 through the pump drive unit 8, thereby placing the righthand main pump I5 in operation. With the lever 66 in the fourth notch II, both 01' the pump driving connections III and I I are placed in communication with the main transmission 6 through the pump drive unit 6. This causes b'oth pumps to be placed in operation. With the lever 66 in the fifth notch "the right-hand pump connection III is placed out of operation, and the left-hand pump connection I I placed in operative communication with the transmission 6 through the pump drive unit 8. This causes .the lefthand pump I6 alone to operate.

When the lever 66 is shifted it passes through a neutral zone. Coincident therewith the driving clutch within the clutch housing 5 is released by the force of the vacuum-actuated device I3, as previously explained. Consequently, the shifting through the various positions is effected without clash of the gearing, and when the lever 66 reaches a. new notch the drive clutch is thereby closed, communicating power from the engine to the main transmission 6.

It will be observed from the foregoing disclosure that the pump driving connections I8 and/or II may be operated either simultaneously with the truck driveshaft 8, as well as independently thereof and independently of one another. This result is effected through the shifting of the hand lever 66 into the five notches 68 to I2, previously discussed. At the same time it will be obvious that the shifting of the lever 83 may likewise be controlled to cause the power take-off l2 and the auxiliary pump to be operated from the main transmission i while the truck is either stationary or in motion. Consequently, the pumping units of the flre engine may be operated either while the engine is stationary or in motion. This enables the use of the flre engine in extinguishing flres which must be followed up, such as grass or brush fires.

It will be understood that I desire to comprehend within my invention such modifications as some within the scope of my claims and my invention.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a flre engine, a major pump, a tank, an auxiliary pump, means for selectively, connecting said auxiliary pump to exhaust from said major pump or to withdraw fluid from said tank, and power means for selectively applying power to said major pump or to said auxiliary pump individually or collectively.

2. In a fire engine, a pair of major centrifugal pumps having intakes and outlets, an auxiliary pump, a tank, transmission mechanism for applying power selectively to said pumps either individually or collectively, valve means for selectively connecting said auxiliary pump to exhaust from said major pumps or to withdraw fluid from said tank, diversion valve means and a cross conduit associated therewith extending from the outlet of one of the major pumps to the intake of the other major pump to connect the discharge of said major pumps in series or in parallel, and check valve means arranged to control the direction of flow from the outlet of the flrst pump and adapted to prevent flow out, of the intake of the second pump.

3. In a flre engine, a pair of major centrifugal pumps having intakes and outlets, an auxiliary pump, a tank, transmission mechanism for applying power selectively to said pumps either individually or collectively, valve means for selectively connecting said auxiliary pump to exhaust from said major pumps or to withdraw fluid from said tank, diversion valve means and a cross conduit associated therewith extending from the outlet of one of the major pumps to the intake of the. other major pump to connect the discharge of said major pumps in series or in parallel, and check valve means arranged to control the direction of flow from the outlet of the first pump and adapted to prevent flow out of the intake of the second pump, and control means for said transmission mechanism and said diversion valve means arranged in close proximity to one another, whereby to facilitate the control of said flre engine from a single station.

4. In a tire engine, longitudinal frame members, a tank mounted above said frame members, a pair of major pumps mounted between said frame members, an auxiliary pump below said tank, and means for selectively connecting the inlet of the-auxiliary pump to the major pumps to cause the priming of the major pumps or to said tank to withdraw fluid therefrom.

CHARLESEFOX.