US2261471A - Adjustable volume control pump and two-stage pump - Google Patents

Description

E. J. HULL Nov. 4, 1941.

ADJUSTABLE VOLUME CONTROL PUMP AND TWO-STAGE, PUMP Filed Dec. 13, 1959 5 Sheets-Sheet l INVENTOR. a? c/'I H01. 1

Y ATTORNEY.

E. J. HULL 2,261,471

v ADJUSTABLE VOLUME CONTROL PUNP AND TWO-STG PUMP Nov. 4, 1941.

Filed Deo. 1.3, 1959 3 vshams-sheet 2 Y E. J. HuL'L 2,251,471 ADJUSTABLE VOLUME CONTROL PUMP AND TWO-STAGE PUMP Nov. 4, 1941.

` 3 Sheets-Shea?l 3 Filed Dec. 13, 1939 \M\.- \N\\/%N\\ m. j ...W Q Nm. G Il mw u.. mm A. p. I..

|\l. .Y A. D mm m QQ, N x S N MQ QS@ Patente 4, ign

ADJUSTABLE VOLUME CONTRL P AND-- TWO-STAGE PURE Application December 13, 1939, Serial No. 309,066

4 Claims.

I be conveniently'and accurately adjusted to adapt the pump for most efficiently pumping and distributing fluids of varying density and viscosity.

It is a further object of my invention to provide such an adjustable capacity pump having a plurality of the pump plungers disposed in a compact circular arrangement around a centrally positioned drive shaft to be driven therefrom, a corresponding plurality of check valve 'plungers circularly disposed in axial alignment with the pump plungers, and adjustable stop means for adjustably liIniting-the inward movement of the valve plungers to adjust the quantity of liquid to be displaced from the inter-port passage by each inward movement of each pum plunger. l

Another object of my invention is to provide an improved two stage pump comprising a pair of such pumps and conduit means so connected that one pump acts as the low pressure stage to supply liquid under pressure into the intake port of the other pump acting as the high pressure stage and means for driving the pump plungers to slide into the guide passages and displace liquid alternately.

, Further objects and advantages are within the scope of my invention, such as relate to the arrangement, operation and function of the related elements of vthe structure, to various details of construction and to combinations of parts, economies of manufacture and numerous other features as will be apparent from a consideration of the specification in conjunction with the drawingsdisclosing specific embodiments of my invention, in which:

Fig. 1 is a longitudinal sectional view through an adjustable pump arranged in accordance with my invention;

Fig. 2 is a cross-sectional view thereof taken on line 2-2 of Fig. 1; Fig. 3 is a cross-sectional view on line 3 3 of Fig. 1;

Fig. 4 is a cross-sectional view on line I--l of Fig. 1; and

Fig. 5 is a longitudinal sectional view of a two stage multiple impeller pump made 'in accordance with my invention,

(Cl. 10S-173) 4 of the drawings, my improved pump comprises a pump block I, which may be a casting of any suitable metal or alloy (not shown) preferably of circular cross section and having a housing or shell 3 extending from one side to enclose a compartment 4. The cross-section of the pump block I yand shell 3 may be either circular, square orA rectangular to provide a suitableshape and compactness required for any particular conditions of installation. I'he extended end of the housing shell 3 is open, and around the inner edge I provide a thick flange 5 for receiving an end c ap 1 secured iirmly thereto as by screw bolts 9 passing through the end cap into the end ange. The inside of, the end cap 'I is provided with acircularange II which ts snugly into the inside of the open end of the pump shell.

As shown in Fig. 1, my pump comprises pump plungers I 3, of which there may be a great number, slidably disposed in suitable guide passages or recesses I5 in snug uid displacing relation with one end extending out into the compartment 4. Adjacent each pump rod I3, an inlet port I'I is provided in the side of the pump body I opening through a passage I9 which extends for connection with the inner end of each guide passage I5. It is apparent that the inlet port may'be located in the casing 3 and that the passage I9 may connect compartment 4 to the inner end of each guide passage I5. From each guidepassage I5, an outlet port 2| is provided, and it is shown as entering through the side of the pump block I although it may enter the bottom thereof or elsewhere, and it opens`i`nto passage I through a passage 23 in said block in spaced relation from the inlet port passage I9. The outer ends of the port openings are provided with enlarged and threaded counterbores 24 for receiving suitable pipe fittings (notshown) for connection with any system as will be understood. An inter-port bore or passage 25 which connects between the inlet and the outlet passages I9- and 23, is in alignment with each guide recess I 5 and also is of a similar diameter for y snugly receiving the inner end of -the pump plunger rod I3 when the plunger is pushed in through the guide recess I5.

Check valve means is associated with each pump-.comprising a valve plunger 29 one end of which slides in snug iluid restricting relation into a valve plunger guide passage 3l in alignment with the inter-port passage 25 and of a similar diameter so that in its innermost posi- Referring more specifically to Figs. '1, 2, 3 and 55 tion the end of the valve plunger passes therein the pump body I.

into. The valve plunger passage 3|. the interport passage 25 and the pump plunger passage I being of the same diameter and opening at opposite ends from the pump body I may be very conveniently drilled as a single bore passing therethrough. The outer portion of each valve plunger 29 slides freely through a suitable aperture 33 in a stationary stop member 35 and has a stop engaging irregularity thereon which may be a flange or shoulder 3l projecting laterally from the outer end for engaging the stop member to limit the inward movement of the valve plunger. A spring guide 39 of smaller diameter extends from the end of the valve plunger 29 to receive and support a compression spring 4I concentrically thereon for continuously biasing the valve plunger to move into the guide passage.

For enclosing the check valve mechanism in a valve chamber d2. a shell it extends from the pump body i and is closed by an end cover plate 45 secured thereon by bolts il passing therethrough into the extended edge of the shell I3. The end cover d5 is provided with a threaded aperture 49 in alignment with each valve plunger 29 and of a suitable diameter to provide for convenient installation or removal of the check valves therethrough. After each check valve plunger 29 and spring M has beeninserted therethrough, each aperture #i9 is closed by a threaded plug 5I which may be screwed'into place by applying a wrench in a suitable aperture 53 provided in the outer end ci the plug. The inner end of the plug 5I is provided with a suitable recess 55 for receiving the outer end of the compression spring lII thereby compressing the inner end of each spring upon each flange 3l for continuously biasing each check valve plunger 29 into its guide passage 3i.

Each valve plunger 29 is moved inward by its spring 4I until the flange 3'I engages the stop member 35 and the inner end of the valve plunger is then so far inserted that it enters the adjacent end of the inter-port passage and positively closes the outlet passage 2l preventing reverse flow of fluid therethrough. In the innermost position each valve plunger 29 serves another purpose besides positively closing the outlet port which is to hold a quantity of liquid entrapped to be compressed by the next movement of the pump plunger 29 into the other end of the interport passage 25.

By varying the innermost positions of the valve plungers 29, the quantity of the entrapped liquid is varied and in this manner the displacement capacity of each stroke of the pump is conveniently varied. This is conveniently accomplished by providing the stop member in the form of a disk having a centrally apertured hub 5l for supporting upon an adjusting shaft 59 which passes therethrough. The inner end of the shaft 59 has an enlarged cylindrical head 6I which is adapted to slide freely into a central aperture B3 From the opposite or outer side of the stop disk 35, the shaft 59 passes through a sleeve il and is threadedV at its outer tion for operatively intermeshing with a corresponding internal thread in said central aperture, as shown.

'I'he outer end of the sleeve 64 has the outer surface 69 formed of any suitable, non-circular conformation for receiving a wrench for turning the sleeve to move the stop disk 35 either toward the pump body -I or to Withdraw it therefrom. In this manner the limiting innermost position of the inner ends of all the valve plungers 29 in the inter-port passages 25 may be conveniently and simultaneously regulated or adjusted to adjust the pumping capacity of the pump.

A cup shaped cover 'II is provided to normally' t over the outer end of the shaft 59 and the adjusting nut 65. The edge of the cover is pro- 'vided with an external -thread 'I3 which seats in an internally threaded aperture 'I5 in the outer side of the cover from whence it may be conveniently removed when the pump is to be adjusted. A passage 'I6 may connect from each inlet port I9 to provide lubricant in the valve chamber 42.

The construction of one of the simplified reciprocating pumps has been described and. in accordance with my invention, a plurality of such pumps may be compactly arranged in a generally circular formationA around the central axis of the pump body for actuation from a single drive shaft. For simultaneously driving a plurality of reciprocating pumps in such a compact assembly. I provide a drive shaft 1s having end portions which are axiallyaligned and an intermediate portion BI which is inclined away from a ccncentrlc or axially aligned relation to'ther end portions. As viewed in Fig. 1, it will be seen that the lower end of the intermediate portion 8i of the shaft is substantially concentric or coend to receive a threaded nut 65 thereon for clamping the sleeve and the stop disk 35 together between the nut on one end and the head on the other end of the shaft, but looselyso that the sleeve can be rotated relative to the stop disk.

The sleeve 64 passes Athrough a central aperture E'I in the end cover 45' and is provided with a suitable external thread of helical conformainciding. with the adjacent end of the shaft, while at the upper end the intermediate portion of the shaft inclines to a position of maximum throw or eccentricity, joining the adjacent end portion of the shaft 'I9 through a drive shaft disk 33. The drive shaft disk 33 is substantially concentric with the adjacent end of the drive shaft 19 having the adjacent disk surfaces substantially perpendicular to the axis of the shaft. The lower face of the drive shaft disk 33 is relatively inclined to be substantially normal to the axis of the intermediate inclined portion 3i' of the shaft.

Any suitable bearing means may be provided for journalling the aligned ends of the drive shaft 31 so that the drive shaft rotates adjacent the pump block I for driving the reciprocating pump rods I3 which projects into the compartment I in a manner to be subsequently described. For journalling the drive shaft in a compact assembly, I have shown the following construction: the lower end of the drive shaft is journalled in the pump block I which has a bearing aperture in a central portion of the inside wall thereof. To reduce friction and wear toa minimum, the bearing aperture may be provided with ring II comprising an outside ball race. the end of the shaft being fitted with a ring 83 comprising the inside ball race '41 for rolling on ball bearings 9| in the usual manner. The upper aligned end of the drive shaft 'I9 extends away from pump block I and passes through an aperture 93 in the end cap plate lI which is preferably similarly provided with a friction reducing ball bearing comprising an inner ball race on the shaft, ball bearings and an outer ball race seated in a suitable bearing aperture. The ball bearing race rings may be a press-fit on the shaft and a push aaarerr t in the bearing apertures in the usual manner. The upper aligned end of the drive shaft 'IS extends through the end cover plate i and projects therefrom for connection with any suitable drive wheel or gear (not shown) which may be secured thereon in any suitable manner as by a key. inserted in the key way 95 in the end of the shaft, as will be readily understood. The aligned end portions of the drive shaft are so journalled that the shaft is disposed substantially parallel to the-axis of the pump rods I3 which slidein the pump housing and centrally with reference to the circular or cylindrical-arrangement thereof. y

To drive the sliding impeller rods I3 with a reciprocating motion as the drive shaft rotates, I provide a wobble sleeve 81 which is journalled on the inclined intermediate portion 8l of the drive shaft so that the shaft rotates freely therein. To reduce friction, the inside diameter of the sleeve 91 is substantially larger than the diameter of the inclined portion of the shaft, on

. which it is Journalled, and is provided at the opposite ends with enlarged counterbores. in which outer ball race ring 99 are seated. The adjacent portions of the shaft are also provided vwith corresponding inner ball race rings iti for rolling on steel ball bearings 063 disposed therebetween so that the sleeve and the shaft are journalled together in practically friction-free relation. Such ball bearings may be selected of different sizes in accordance with goed machine design practice to properly carry the diering loads at different positions, as will be understood.

To hold the wobble sleeve S'l from rotating as the shaft rotates, any suitable means may be employed. In the drawings, I have shown a plurality of stationary guide pins m5 which are hrmly seated, as by threading, in suitable apertures iiili in the inside wall of the pump housing from which the guide pins project into the enclosed compartment f3. The projecting ends of the sta tionary guide pins project into corresponding guide apertures it@ in the adjacent end o the sleeve Qi. In this manner the wobble sleeve iii is held from rotating so that as the drive shaft rotates the sleeve is non-rotatively rocked by the inclined portion of the shaft. For lubricating purposes one such pin 05 has been found suiiicient, provided itis of sumcient strength to carry the maximum load.

By providing operative engagement between the wobble sleeve S7 and the sliding impeller rods i3, these are caused to reciprocate as the drive shaft rotates. For this purpose the end of the wobble sleeve adjacent the pumpv block I is provided with a plurality of laterally extending arms II I which correspond in number and position to the number of pump rods to be driven. The outer end of each arm III projects into an aperture in a pivot block Ii3 which may be of Y substantially larger diameter having a shell H5 of a suitable bearing metal therein. As shown in Fig. 3, each pivot block H3 is provided on opposite sides with pivot pin recesses for receiving the inner ends of pivot pins IIl which are threaded through two spaced forks I I9 extending in spaced relation from the end of the pump rod I3. The lower or inner surface of each pivot block IIS is preferably a convex curved surface of revolution in order that the pivot block may be fitted up snugly to the end of the impeller rod, as shown in Fig. 1. Each arm III extending laterally from the wobble sleeve 91 is pivotally where it is shown in combination with a double connected with its corresponding pump plunger I3, in a similar manner.

In operation, as the drive shaft rotates, the stationary guide pins it cause the wobble sleeve @l to rock in a non-rotative manner to impart a motion of reciprocation to the impeller rods. As each impeller rod i3 is pushed into the adjacent end of the-interport passage 25, Aliquid is trapped therein which can not return to the inlet port. As themotion of the impeller rod. continues, the trapped duid is pushed along and forcefully expelled through the outlet port 2i as the valve plunger 29 is pushecleack. As the motion of the impeller rod I3 r 'etsen-initie reverse flow of the expelled iiuidtis restricted by valve plunger 29 entering interport passage 25 and closing the outlet port and when the rod is withdrawn from the mierport passage as amd rushes in from the inlet port ii to fill the space evacuated by the impeller rod.

The quantity of liquid which enters the interport passage 25 tov be entrapped by the pump plunger for-forceful propulsion from the outlet -port depends upon the innermost position assumed by the inner end of each check valve plunger 29 which ls determined by the position of the stop member 35. .By removing the cup cap il and turning the threaded sleeve Bt, the stop limit disk 35'4 can be moved in or out for simultaneously and conveniently adjusting the stroke capacity of all the pump plungers as previously set 'forth in detail. v

.It will be understood that the inlet ports i@ and the outlet ports 2| may all be separately conductive or that by suitably conductive connections these may be grouped to draw all the liquid from a single source or grouped from and to different connections as desired.

It will be seen that I have provided an adjustable multiple impeller reciprocating pump which is of a compact simpliiied construction.

The innermost positions of each check valve plunger may also be adjusted separately and individually for each check valve by providing the adjusting arrangen1ent..shown in Fig. 5,

acting type of pump. My adjustable double acting pump shown in Fig. 5 is a compact assembly generally similar to that previously described, comprising, as it does, a pump block or body I having a shellj extending from one side for enclosing a chamber d in which is housed a drive shaft i9 for actuating power transmitting and translating mechanism having similar elements tl to I 09 for reciprocating pump plungers into and out of guide passages in the pump block. l

My double actingpump shown in Fig. 5, comprises pump plungers arranged in cooperative pairs, one plunger .IZI being large for supplying liquid under low pressure to the other plunger H23 whiclris small for ejecting the liquid from the pump for high pressure distribution. The

large or low pressure plunger I 2i and the small ,l or high pressure pump plungeri23 each slide into respective guide passages I25 and I2`i of suitable diameter whichI pass through the pump block I An inlet port ISI opens info the pump body and intercepts the larger passage G25 at a point in the space traversed by the inner end of the low pressure plunger I21I to be opened and closed thereby. An internal outlet passage |33 opens -within said block from the large passage H25 at a point beyond thetraverse of the large plunger andV extends in the pump block to connect throught an axial passage i35 with an internal inlet passage ist intercepting the smaller passage B2i at a point in the space traversed by the smaller plunger to be opened and closed thereby. Theinternal passages i433, i235 and 31 being so interconnected transmit the fluid discharged by the low pressure plunger |211 into the inlet port of the high pressure guide passage |21. An outlet port |39 opening from the pump block intercepts the smaller passage |21 at a point beyond the traverse of the smaller piston. As shown, the internally extending interconnected passages |33, |35 and B31 are conveniently drilled from the exterior of the body, theouter ends being plugged by any suitable plugs M which may be-pressed therein. t will be seen that the guide passage |25 of the low pressure pump may be regarded as divided into three sections by the two ports which open thereinto. As in the previously described pump, the portion between the two ports is for convenience referred to as an inter-port passage |4| and the lower portion as a check valve guide passage |43. Similarly the passagedrilled forf the high pressure pump plunger has an inter-port portion |45 and a check valve guide passage |41.

Sliding into the valve guide passages are check valve plungers |49 and |5| of suitable diameters to t in snug fluid restricting relation into the valve guide passages |43 and |41 respectively. Each valve plunger is provided with an extension |53 which extends outwardly and passes freely through a suitable aperture |55 in a stationary stop member |51. The stop member |51 is secured rigidly to 'the ends of brackets |59 projecting from the pump block by bolts |5| passing therethrough. The extension |53 of each valve plunger between Vthe pump block and the stationary stop member |51 carries a compression spring |63 concentrically disposed thereon, which by reaction between the stationary stop member and a spring stop |65 on each valve continuously urges each valve plunger to slide into its respective guide valve passage. The entrance o! each valve plunger into each valve passage closes the outlet port cutting it off from the adjacent inter-port passage to prevent the reverse flow of liquid therethrough.

The final innermost position of each valve plunger as it moves in toward the associated inter-port passage serves also to determine the quantity of liquid which will be entrapped for expulsion by the next inward motion of thel pump plunger.

To limit the inward movement and the iinal' inward position of each check `valve plunger, the outer end of each extension |53 of each plunger'is threaded and-provided with a pair of nuts |51 threadably received thereon. Only one plunger |53 could be shown complete with the pair of stop nuts |61, the other plungerbeing shown as broken oil?. The nuts |51 form an adjustable stop which by. striking the side of the stationary stop member |51 limits the inward movement of the valve plungers. `By applying suitable wrenches and turning the nuts of any pair apart these may be loosened and the inner one adjusted to a desired position. The other or outer nut is then turned against the inner one which is held stationary by a wrench, and any pair of stop nuts thus may be conveniently adjusted. The respective check'valve plungers may in this` convenient manner be each adjusted individually and separately.

For maximum capacity of any pump, the innermost end of the associated valve plunger` must meenam be adjusted so that it will just barely enter the inter-port passage just sufficiently to close the outlet port to act as a check valve. To adjust any pump for its minimum capacity, the pair oi.' stop nuts on the valve extension are turned back until the inner end of the valve plunger in its innermost position approaches very close to the inlet port.

In operation, the drive mechanism moves the high pressure plunger and the low pressure plunger of each pair alternately in and out of the pump block, As the large low pressure plunger l2! is drawn out of the guide passage |25, liquid rushes in through the intake port |3| to fill the space thereby evacuated. The large pump plunger |2| next moves into the guide passage closing the inlet passage |3| and trapping the liquid in the interport portion |4I oi the passage so that it is forcefully moved toward the check valve plunger |49 pushing same from the opposite end of its guide passage |43 and opening the outlet passage |33 through which the liquid is discharged to the inlet |31 of the high pressure pump. On the low pressure pump check valve, the spring |53 is strong enough to push the valve plunger |49 in to expell al1 the liquid and to abut the adjacent end of the pump plunger, substantially as shown at the right hand side o! Fig. 5.

When the low pressure pump plunger |2| is in its inner-most position for expelling liquid, the high pressure plunger |23 is at its outer position, and its inlet port |31 is opened for receiving the liquid which is injected forcefully therein to flll the inter-port passage |39 with liquid free from bubbles or vacuum spaces even when operating at high speeds and when used for dispensing various different grades of oils and greases.

While the high pressure plunger |23 is moving in for expelling liquid under high pressure from outlet port |39, the low pressure plunger |2| is moving out to draw in the next charge. Such operations are continued successively as long as the pump is operated and the liquid is supplied to the intake port of each pair of pump plungers.

It is apparent that within the scope of the invention, modifications and diierent arrangements may be made other than herein disclosed, and the lpresent disclosure is illustrative merely, the invention comprehending variations thereof.

I claim:

1. A compact adjustable-capacity multipleim peller pump comprising, a pump block, a plurality of guide passages in said pump block and opening therefrom at the opposite ends, said guide passages being disposed substantially parallel to each other in a substantially cylindrical arrangement, in said pump block, an inlet port and an outlet port opening into each guide passage at axially spaced points therein, a pump plunger slidable backrand forth in fluid displacing relation in the end of each guide passage adjacent the inlet port for opening and closing the inlet portland i'ormoving entrapped fluid through the inter-port passage'toward the outlet port, a drive shaft journalled substantially centrally with reference to the cylindrical arrangement of the guide passages in the pump block, power transmission means operatively connecting between said drive shaft and the pump plungers for vreciprocating the plungers as the .shaft rotates,

assign limiting the movement of each valve plunger intoy each passage, and support means passing through a central aperture in said stop disk for adjustably supporting said stop disk for movement to various positions relative to the pump block to adjustably predetermine the quantity of entrapped liquid in the inter-port portion of each passage to be displaced by each inward movement of each pump plunger.

2. A compact adjustable-capacity multipleimpeller pump comprising, a pump block, a plurality of guide passages in said pump block and opening therefrom at the opposite ends, said guide passages being arranged substantially parallel to each other in a substantially cylindrical relation in said pump block, an inlet port and an outlet port opening into each guide passage at axially spaced points in the passage, a. pump plunger slidable back and forth in fluid displacing relathrough the interport passage toward the outlet port, a drive shaft journalled substantially in central axial alignment with reference tothe cylindrical arrangement of the guide passages in the pump block, powerltransmission means operatively onnecting between the drive shaft and the pump plungers for reciprocating the plungers as the shaft is rotated, a vcheck valve plunger slidably disposed in the other end of each guide passage adjacent the outlet portfor opening same for discharging iiuid from the interport passage and closing same to prevent the reverse flow of uid, means continuously biasing each valve plunger to move into its guide passage beyondA the outlet vport and into the .interport passage, one end of each valve plunger projecting at all times from the guide passage, a stop' engaging irregularity on the extended end oi.' each valve plunger, a stop disk having apertures `disposed in a circular arrangement for receiving the extending ends of all the valve plungers passing therethrough to catch the irregularities thereon for limiting the movement of each valve plunger into `each passage, a support shaft secured at tion in the end of each guide passage adjacent the inlet port for opening and closing the inlet port and for moving entrapped iiuid through the interport passage toward the outlet port, a drive shaft journalled substantially in central axial alignment with reference to the cylindrical arrangement of the guide passages in the pump block, power transmission means operatively connecting `between the drive shaft and the pump plungers for reciprocating the plungers as the shalt is rotated, a check valve plunger slidably disposed inthe other end of each guide passage adjacent the outlet port for opening same for discharging fluid from the interport passage and closing same to prevent the reverse ow of uid, means continuously biasing each valve plunger to move into its guide passage beyond the outlet port and into the interport passage, one end of each valve plunger projecting at all times from the guide passage, a stop engaging irregularity on the extended end of each valve plunger, a stop disk having apertures disposed in a circular arrangement for receiving the extending ends of all the valve plungers passing therethrough to catch the irregularities thereon for limiting the movement of each valveplunger into each passage, and support means for adjustably supporting said stop disk for movement to various positions toward or away from the pump block to adjustably predetermine the quantity of uid en'-y trapped in the interport passage to be displaced by each inward movement of each pump plunger.

3. A compact adjustable-capacity multiple- .impeller pump comprising, a pump block, a pluallel to each other in a substantially cylindrical relation in said pump block, an inlet port and an outlet port openingV into each guide passage at amally spaced points in the passage, a pump plunger slidable back and forth in iiuid displacing relation in the end of each guide passage adjacent the inlet port for opening and closing the inlet port and for moving entrapped iluid one end to the center of the stop disk and extending axially therefrom, an axially adjustable sleeve for adjustably supporting said support shaft for axial movement` to various positions to move the stop disk toward 'or away from the pump block to adjustably predetermine the quantity of uid entrapped in the interport passage to be displaced by each inward movement of each pump plunger.

4. A compact adjustable-capacity multipleimpeller pump comprising, a pump block, apiurality of guide passagesin said pump block and opening therefrom at the opposite ends, said guide passages being arranged substantially parallel to each other in a substantially cylindrical relation in said pump block, .an inlet port and an outlet port opening into each guide passage at axially spaced points in the passage, a pump plunger slidable back and forth in fluid displacing relation in the end of eachguide passage adjacent the inlet port for opening and closing the inlet and closing same` to prevent the reverse flow of uid, means continuously biasing each valve plunger to move into its guide passage beyondu the outlet port and into the interport passage,

one end of each valve plunger projecting at alll times from the guide passage, a stop engaging irregularity on the extended end of each valve plunger, a stop disk having apertures disposed in a circular arrangement for receivingthe extending ends of' all the valve plungers passing therethrough to catch the irregularities thereon for limiting the movement of each vvalve plunger into each passage, said stop disk having an aperture centrally disposed therein, a support shaft extending through the central aperture in the' disk, a projection on the end of the shaft adjacent the pump block for engaging the disk, the other end of said shaft extending away from the 6 eenen 5 pump plunger.

to various positions toward or awhy from the pump block to adjustably predetermine the quantity of fluid entrepped in the interport passage to be displaced by each inward movement ofeach EDWN HULL

Images