US2266204A

US2266204A - Liquid dividing and dispensing system

Info

Publication number: US2266204A
Application number: US305229A
Authority: US
Inventors: Edwin J Hull
Original assignee: TRABON ENGINEERING CORP
Current assignee: TRABON ENGINEERING Corp
Priority date: 1939-11-20
Filing date: 1939-11-20
Publication date: 1941-12-16
Anticipated expiration: 1958-12-16

Description

Dec. 16, 1941. 1 E. J. HULL 2,266,204

LIQUID DIVIDING AND vDISYPENSING: SYSTEM 2 Sheets-Sheet 1 I Q INVENTOR.

70W/M cl ffl/l L.

ATTORNEY.

Similarly, piston rod I5 has an enlarged hub 3| with

grooves

33 and 35 on either side. Next to the

grooves

33 and 35 are the piston valves 3l and 39. Located near the ends of piston rod I5 are the pistons or pump plungers 4| and 43 which t in the end pump chambers respectively of cylinder 5.

Cylinder 3 is provided with dual service or end ports 45 and 4l respectively at each end thereof and cylinder 5 is similarly provided with dual service or

end ports

49 and 5|.

The ends of both piston rods |3 and I5 project beyond the pistons or pump plungers so as to prevent the closing of the dual service ports. Any other suitable abutment may be provided for permitting ow of fluid into the end chamber when the associated piston is at the outer end of its stroke. Y

A central passage 53 connects the central portions of

cylinders

3 and 5. In this passage I preferably locate control means cooperating with the hub and grocved portions of the two piston assemblies to prevent simultaneous movement of said rods. It is evident that the hubs |1 and I9 could be located elsewhere and a separate passage could be provided for the means for preventing simultaneous movement o the piston rods, but for economy and compactness I prefer to locate them as shown.

It has been the practice to provide a pin to act as a stop member and to prevent simultaneous movement of two such valves, but it has been found that great wear takes place on the contacting heads of said pin type of stop member. I have therefore provided two balls 55 and 5l for contacts, using a small spacer 59 between them, the overall length of the balls and spacer being greater than that of the passage 53 in which they are adapted to operate. The balls give a rolling contact and assure longer life to the device. The diameter of each of the balls 55 and 5l as Well as that of the spacers 59, in this embodiment, is less than that of the passage 53, as fluid must be able to pass through the passage 53 at all times that the device is in operation; The control balls and spacer are actuated by the movement of the pis-- tons andare not unduly restrained by gravity.

It is evident that the balls and spacer act als' the pin previously acted in conjunction with the hubs and 3| and the adjacent grooves of the respective piston rods in forming a control mechanism which prevents the piston rods from moving at the same time, thereby avoiding failure of operation which might otherwise result if the fluid pressure should be discontinued while the piston rods were passing dead center or if they got in that position when the device was not in operation as by action of gravity or vibration for example.

Adjacent the central portion of each cylinder, two additional dual service ports are also provided in each cylinder, 69 and 19 in

cylinder

5 and 89 and 99 in cylinder 3. It will be noticed that said ports are located in such spaced relation that the piston valves on each side of each associated piston hub are adapted to establish conductive connection between one or the other of said end dual service ports in Yeither cylinder and one or the other of the centrally located dual service ports in the other cylinder. For this reason, these four

dual service ports

69, 19, 89 and 99 are also called control ports. This arangement of the ports and piston valves in the lower cylinder 5 serves to pass fluid from sci . port |03.

.3) with dual service port 69 (located near and to the right of inlet port |I in cylinder 5). Circuit pipe line 1| -connects dual service or end port 4l (located at the left of cylinder 3) with dual service port '|9 (located near and to the leftof inlet port in cylinder 5). Circuit pipe line 8| connects dual service or end port 49 (located at the right of cylinder 5) with dual service Vport 89 (located near and to the left of the opening of passage 53 into cylinder 3).

Circuit pipe line 9| connects dual service or end port 5| (located at the left of cylinder 5) with dual service port 99 (located near and to the.

right of the opening of passage 53 into cylinder 3).

Each of the pipe lines which interconnect between the dual service ports of the device also may have connected therein a reversible feeder of the nature shown in the U. S. Patent Number 1,997,406 issued to David R. Hillis on April 9, 1935, or any number thereof in series. Also only such lines as it may be desired to usefor dispensing liquid may be provided with reversi- 35- b le feeders.

I have shownv each line as having a series of twoffeedersjthe line 6| having feeders 63 and 6l each having a discharge pipe line'65 connected thereto; the line having feeders l13 and 'Il each having a discharge pipe line 15 leading therefrom; the line 8| having feeders 83 and 8'IV each having a discharge pipe line 85 leading-therefrom; theline 9| having feeders 45,; 93 and 9'| *each having ra discharge pipe line 95' leading therefrom.

- Two exhaust passages |0| and |93, lead from cylinder 3, being so spaced that, when piston rodVK I3 is at its extreme left position, dual service port 99 may communicate with exhaust passage |03, fluid flowing through said port 99 from pipe line 9| may then pass around the reduced portion of piston rod |3 between piston valves 23 and 21 and pass out of the exhaust Similarly when piston rod I3 is at its extreme right position, iluid coming into cylinder 3 from pipe line 8|, through dual service port 89, will pass around reduced portion of piston rod I3, between

piston valves

25 and 29, and thence pass out of the exhaust port |9|.

Similarly spaced exhaust passages IIa and |93a. also lead from cylinder 5 to cylinderV 3 for exhausting vfluid that returns through pipe lines 'Il and 6| respectively toV cylinder 5, said fluid being passed to the respective exhaust portions of cylinder 3 and its respective exhaust ports |9| and |03 which are connected to piping |95 leading to a reservoir or the pump sump.

Cnthe right hand end of piston rod I5 I have provided`an indicator rod |09 which extends through the nut 9, the nut being provided with the usual packing. Of course a plurality otindicator rods could be providedbut as long as the workman in attendance sees one indicator move, -he knows that the device is still operating satisfactorily.

(Iteration A source of uidunder pressure is connected to the inlet port II. For instance, a pump may be connected directly or by a pipe line III to the inlet port Il. Well-known relief Valves are used for exhausting air and filling the system. Hence let us assume the system is lled with grease hfor lubricating bearings connected to the discharge pipes leading frorn the respective feeders and assume that the parts are in the positions shown in Fig, l.

Grease will then pass around hub 3| in cylinder and out of dual service port 19, into pipe circuit l|, discharge a measured quantity of grease from feeder 71, out of discharge pipe v15, then by-pass and through the continuation of pipe line 1| leading to feeder 13, discharge a measured quantity of grease from lfeeder 13 and pass en through the remainder ef pire `line 1l, through dual service port 41 and into the left hand Aside of cylinder 3, causing piston rod I3 to shift to the right.

It should be noted that while the passage 53 is open at all times, grease will not pass therethrough while the'above operation is taking place las the passage 53 and the portion of cylinder 3 between

piston valves

23 and 25 and the dual service port 89 and pipe line 8| with its feeders 81 and 83 have just previously functioned to shift piston assembly l5 to the left, and inlet pressure is now holding the same in its extreme left position.

`When the grease has completed its circuit through pipe line '|I from dual service port 19 to dual service port 41, it then shifts piston rod I3 to the right, forcing the balls 55 and 51 and the spacer 59 downwardly in passage 53, so that ball 51 will rest in groove'33, as shown in Fig. 2, thus preventing piston rod I5 from moving simultaneously therewith, as itsfluid holding pressure is now relieved.

The grease in the right hand chamber of cylinder 3 is now discharged as by the pumping action of plunger 21. It then passes through dual service port 45 into pipe line 6|, operates

feeders

63 and 51 and enters cylinder 5 through dual service port 69, passing around reduced portion of piston rod I5, between piston valve 31 and piston 4|, from whence it is free to exhaust through passage ||J3a into cylinder 3, between piston valve 23 and piston 21, which always are in position to open to exhaust passage I 03, thence through pipe line |95 to the' reservoir or sump of a pump. Y

Piston rod |3 is now `held in its right hand position, as shown in Fig. 2, by the pressure of the grease entering the inlet port. Thispressesthe grease in line '|I against the piston 29 of piston rod I3 until the pressure 'later is relieved by movement of pistenrod I5 to the right, at which time ball 55 Wili be forced into groove 2| to hold piston rod I5.

After piston rod I3 has moved to the right, as seen in Fig. 2, grease will then pass from the inlet port through passage 53 and around hub I? in cylinder 3 and out thereof through dual service port 99, into vpipe line 9|, operate feeders 9`| and 93 and pass through dual service port 5| into the left end chamber of cylinder 5,

forcing piston rod I5 to the right, which action70 forces the balls and spacer up to the position shown in Fig. 3.

The movement of piston rod I5 to the right alsov causes piston 4I te discharge the grease from the right hand chamber `of cylinder 5,

through dual servceport 49, pipe line 8|, Voperating ,feeders 83 and .87,and the balance of said discharged'grease, beyond that of the capacity of feeders 83 and |31, displaces a like quantity of grease in the line, causing it to reenter cylinder 3 through dual service port B9 and to dis-` charge into the exhaust, through exhaust port IBI, a like amount.

After both pistons have arrived at the right, as shownin Fig. 3, grease now ows from inlet port II into cylinder 5, around hub 3| and out dual service port 69 into pipe line 3|,

operating feeders

67 and 63 and entering into the right hand en d of cylinder 3, ,through` dual service port 45, forcing piston rod |3 to the left. This action forces the balls down as shownin Fig. 4 and also displaces the grease in the chamber at the left end of cylinder 3, causing flow of grease out of dual service port 41, through pipe line '|I, `operating feeders '|3 and 'I1 and into cylinder 5, through dual service portr 19 which then registers with that portion of piston rod I5 between piston valve 39 and piston 43 that registers with exhaust passage I9 lafhence it may exhaust through passage I Bla and through cylinder 3 between piston valve 2,5 and piston 29 and exhaust port Ill and exhaust pipe line I 95.

Grease now passes from inlet por-t II through the centralportion of cylinder 5 and passage 53 into central portion ofcylinder 3, around hub and outof dual service port 89 into pipe line 8|, operating feeders 81 and .8 3 and passing through dual service port li9 into the right hand chamber of cylinder 5, forcingpiston rod I5 to the left. This forces the balls to the position shown in Fig. l and displaces the grease in the chamber at the left of cylinder 5, causing flow of grease in pipe line 9|, operating feeders 93 and 9iY and passing through dual service port 99 into cylinf der 3 between piston valve 23 andpiston 27 from whence it is free to exhaust through exhaust port |93.

Y Care should be taken tosee that the capacity of the total number of feeders connected to any one line is less thanthe capacity of the `chamber at the end of any cylinder which discharges through the line.. e v

Aside Vfron/ 1 the specic embodiment of .the invention herein shownrand described, it will be understood that numerous details of the con:` SiTuQtOn may be altered or omitted without de: parting from the .Spiritand scope .0f the inven.-l tion as disclosed and claimed, and that I .do not desire to limit the invention to the .exact construction herein set forth.

I claim:V

l. A dispensing ,System iomprising. a plurality of conduits, each conduit being provided with a, reversiblv operated dispensing and byfpassing feeder, a body having. .a plurality of dual service' ports, each end of each of said conduits being CQIineied te .a @dieren-tone of said `dual service ports in the` body so that each conduit forms.

a Circuit leading from .and returning te said Y body, an inlet port infsaid 'body adapted to ref ceive fluid under pressure, exhaust port means in said body, uid flow conducting passages in said body conductively connecting between said inlet por-t, dual service ports and said exhaust port means, and two movable members in said body operable by said duid under pressure in said inlet port in cooperation with each other and with said passages and ports to reverse the direction `of flow of fluid in said conduits in time-sequence relation. Y

2. A dispensing system comprising, a plurality of conduits, each conduit being provided with a dispensing and by-passing feeder, a body having a plurality of dual service ports, each end of each of said conduits being connected to a different one of said dual service ports so that each conduit forms a circuit leading from and returning to said body, an inlet port in said body adapted to receive fluid under pressure, exhaust ports in said body, fluid flow conducting passages in said body conductively connecting between said inlet port, said dual service ports, and said exhaust ports, and movable means in said body for directing uid through each of said conduits in time sequence relation, said movable means being operable by said fluid under pressure and adapted, in cooperation with said passages and ports, to reverse the direction of flow of fluid in said conduits.

3. A dispensing system comprising, a plurality of conduits, each conduit being provided with a dispensing and by-passing feeder, a body having a pair of cylinders, a plurality of dual service ports in said body, half of them opening into and leading from each cylinder, each end of each of said conduits being connected to a different one of said dual service ports so that each conduit forms a circuit leading from and returning to said body, an inlet port in said body opening into the central portion of each cylinder adapted to receive fluid under pressure, piston assemblies in each of said cylinders operable by said fluid under pressure in passing through the system for controlling and reversing the direction of ilcw of fluid in said conduits in time sequence relation, and exhaust outlets for exhausting returned fluid which has not been dispensed.

4. In combination in a system for dividing and distributing uids, a body having a pair of cylinders closed at the ends, a reciprocating piston assembly slidably disposed in each cylinder including a piston rod and two pistons near the outer end and two spaced piston Valves near the middle portion of said rod, said pistons and piston valves fitting the cylinders in fluid retaining relation and spaced apart by portions of smaller diameter of said rod, providing fluid receiving and passing spaces between, one of said fluid receiving spaces being disposed at the central portion of each piston assembly, each said piston assembly having two outer spaces, a central passage in the body connecting between said central spaces, an inlet port in said body opening into the central space of one of the piston assemblies and connecting to the central space of the other piston assembly for admitting high pressure fluid therein, each cylinder having an end port adjacent each end for applying fluid pressure on the end of the adjacent piston for moving the piston assembly to the other end of the cylinder, four control ports, two in each cylinder spaced on each side of the center thereof, said ports being opened and closed by the movements of the piston assemblies and so arranged that each assembly controls the application of fluid pressures selectively on the ends of the other piston assembly to move both piston assemblies to and fro as long as fluid pressure is applied into said inlet ports, two exhaust port passages opening through the side walls of each cylinder at points on opposite sides of the center and suiiiciently spaced toward the ends of the cylinders from said control ports to avoid being connected with the central space of the piston assembly in either position thereof and to connect with the outer space of each assembly when it is moved toward the center of the cylinders, four control conduit lines, one connecting from each control port and extending externally of said body and returning to said body connected into one of said end ports for applying actuating fluid pressures therein, and a fluid measuring, dispensing and by-passing feeder disposed in one or more of said control lines -for operation to measure and dispense a portion of the control fluid received from its line and adapted-to by-pass additional fluid to the continuation of its line.

5.` In combination in a system for dividing and distributing iiuids, a body having a pair of cylindersclosed at the ends, a reciprocating piston assembly slida'bly disposed in each cylinder, each piston assembly including a rod and two piston valves spaced'on opposite sides of and adjacent the center and two pistons spaced adjacent the opposite ends, said pistons and piston valves tting the cylinders in fluid retaining relation and being spaced apart for providing fluid receiving and passing spaces between, one of said fluid receiving spaces being disposed'at the central portion of each piston assembly, a central passage connecting between said central spaces, two exhaust ports connecting through the side Walls of each cylinder and suitably positioned for connecting the space between the piston valve and the piston at each end of each piston assembly with the corresponding space in the other piston assembly in all movable positions of both piston assemblies, an inlet port in said body opening into the central space of one of the piston assemblies for admitting high pressure fluid therein, each cylinder having an end port adjacent each end for applying ,iiuid pressure on the end of the adjacent piston for moving the piston assembly to the other end of the cylinder, control ports opened and closed by the movements of the piston assemblies and so arranged that each assembly controls the application of uid pressures selectively on the ends of the other piston assembly to move both piston assemblies to and fro as long as fluid pressure is applied into said inlet ports, control conduit lines connecting one from each control port and extending externally of said body and returning tosaid body connected into one of said endports for applying actuating uid pressures therein, and a iiuid dispensing feeder disposed in one or more of said control lines for operation to dispense a portion of the control iiuid which is passed through said control conduit line for actuating said piston assemblies.

6. In combination in a system for dividing-and distributing fluids, a bodyhaving a pair of guide cylinders therein, a reciprocating piston rod in each cylinder, a pair of pistons on each rod adjacent the outer ends thereof, a pair of piston valves on each rod near the mid-portion thereof,`

said piston valves being spaced apart and also spaced from the pistons to provide fluid receiving spaces therebetween; an inlet port in said body connecting into the space between two of said piston valves in one cylinder and connecting into the corresponding space in the other cylinder for receiving high pressure uid therein, exhaust passages in said body opening one from each space between each piston valve and each piston of each cylinder, dual service ports suitably positioned in said cylinder and interconnecting control conduits connecting from and between the dual service ports of said cylinders to cause saidpiston assemblies to ,reciprocate continuously in response-to fluid injected' under pres- `fluid in reversing flow relation in said conduits,

said control conduits extendingfexternally of said body, and a fluid'dispensing feeder device disposed in one or more of said-control lines for operation to dispense a portion of the control uid passing therethrough. Y

'7. In combination in a system for dividing and distributing fluids, a -body having a pair of cylinders closed at the ends, a reciprocating piston assembly slida-bly disposed in-each cylinder, each' piston assembly including a piston rod having two piston valves near the mid-portion thereof and two pistons, one adjacent each end thereof, said valves and pistons .tting'the cylinders in duid retaining relation andA said valves being spaced apart and alsospaced from the pistons to vprovide iiuid receiving and passing spaces therebetween, one of said fluid .receiving spaces being disposed at the central portionof 'each piston assembly, a central passage connecting'between said central spaces, control means in said central passage actuable by either piston assembly .moving from an extreme position to secure the otherpiston assembly in an extreme position until the other has reached an extreme position, an inlet port in said body opening-into the central space of one of the piston assemblies .for admitting high pressure fluid therein, each cylinder having an end `port adjacent each enjd' for applying fluid pressure on the end of the ad.- `ia-cent piston for moving the piston assembly to the other end of the cylinder, four control ports opened and closed by the movementsof the piston assemblies and so arranged that each assembly controls the application of fluid pressures selectively on th'e ends of the other piston assembly Yto move both piston assemblies to and fro as long as fluid pressure is applied into said inlet port, four control conduit lines connecting one from each control port and extending externally of said body and returning to said body connected into one of said end ports for applying actuating uid pressures therein, a reversibly operable fluid dispensing feeder disposed in one or more of said control lines for operation to dispense a portion ofthe con-trol fiuid passed therethrough, exhaust ports in said body opening from the uid receiving spaces between the piston valves and the pistons, spaced apart on opposite sides of' the center of each piston assembly, and fluid conducting lines connecting from respective ones of said exhaust ports adapted for returning some of the distributing fluid to a reservoir or sump of a pump.

8. An apparatus for dividing and distributing fluids comprising, a body having two cylinders closed at the ends, a piston assembly slidably disposed in each cylinder, eachi piston assembly including two piston valves and two pistons sliding in uid retaining relation in the cylinder and rigidly spaced apart with the two piston valves on each side of the center of the assembly providing uid receiving spaces between said piston valves and the pistons being spaced outwardly therefrom and providing intervening spaces, each cylinder having a dual service end port adjacent each end for receiving fluid under pressure to apply on the adjacent end of the adjacent piston for moving the piston assembly to the other end of the cylinder and for discharging fluid therefrom when pressure is applied on the other end of the piston assembly, additional dual service ports, one complementary to and .5 cooperating with eaehlof said Send .ports Aand opening through an intermediate portion .of fthe rotherclylinder side wall for vcontrol blyv an inner piston Ivalveof zthe piston assembly therein, four conduits, `one connecting each dual service end port .to its complementary dual service con-trol port, a vreversibly operable Vand ley-passing feeder connected to each conduit, .an inlet port rin .said lbodyopening into- :each cylinder at the .cen-

tral space of .each of the pistonassemblies, two exhaust passages :connecting between the two cylinders :and .opening intov the spaces between .the valve pistons 1and the :pistons of each assembly, andzexhaust passages connecting and opening therefrom ,for exhausting undistributed fluid returning A`to' .the apparatus.

.9. Apparatus for distributing fluids comprising, .a body member having a pair of cylinders therein, a reciprocating piston'rod in each cylinder, a pair of pistonsfon each rod adjacent the outer ends thereof, a pair of piston valves on each' rod near the mid-portion thereof, said piston valves vbeing spaced apa-rt and also spaced `lfrom the pistons ,to provide fluid receiving spaces therebetween, an inlet Vport in said body connecting into each cylinderfat the space between t-woof said piston valves for receiving high pressure duid therein, ,ports suitably positioned Vin said cylinders in cooperative relation to said pistons and piston valves, interconnecting conduits connecting from and between the ports in said cylinders to cause said piston assemblies to reciprocate :continuously in .response t0 fluid i11- 'ieted under .pressure into .Said inlet port, 011e of said conduits `vbeing adapted for connection to ya reversibly operable dispensing and by-passing feeder, two spaced vexhaust passages connecting through the body between the spaces between each adjacent piston valve and piston, and .exhaust passages connecting and opening therefrom. Y p

1.0. Apparatus for distributing fluids including thecombination set fOIth in claim number -6 and .also having-.means forpreventing movementof both piston rods at the same time.

11. A uid dispensing Vsystem comprising, a body having a cylinder therein, four dual service ports in said body opening into said cylinder at axially spaced points, one at each end thereof and one on each side of the center thereof, another cylinder in said body, four dual service ports in said body opening similarly into said second mentioned cylinder and corresponding in position to the ports opening into the rst cylinder, four conduits, each conduit connecting from one of the dual service end ports of one cylinder to one of the dual service ports in the mid-portion of the other cylinder, an inlet port in said body opening into said cylinders to receive uid under pressure th'erein, piston assemblies in each of said cylinders opera-ble by the uid under pressure in passing through the system for reversing the direction of flow of uid in said conduits, exhaust ports opening from the cylinders for exhausting some of the returned fluid, a fluid dispensing and by-passing feeder disposed in at least one of said conduits for operation by the uid passing reversely therethrough, and exhaust passages leading from said exhaust po-rts for exhausting undispensed fluid returning to said cylinders from said conduits.

12. A iiuid distributing system comprising, a body, a plurality of cylinders in said body, a plurality of ports opening into each of said cylinders at corresponding similar points, some being adjacent the ends thereof and others being spaced intermediate the ends of the cylinders, conduits connecting the ends of each cylinder into another cylinder, an inlet port in said body for receiving fluid under pressure therein, conduit means connecting each cylinder to the inlet port for the flow of fluid through all the cylinders, a piston assembly in each cylinder arranged to be automatically shifted back and forth between two extreme positions by the fluid under pressure, each piston assembly having spaced pistons and piston valve means so spaced and positioned relative to said ports as to alternately connect the ends of the cylinders to fluid under pressure and to alternately connect the cylinders at their opposite ends to outlets in other cylinders through said conduit means whereby said piston assemblies continuously reciprocate to discharge iiuid from opposite ends thereof so long as fluid under pressure is provided, one or more of said conduit means consisting of a pipe or pipes extending externally of said body, fluid dispensing and by-passing feeders connected into such external pipeV or pipes for operation by the fluid passing reversely therethrough, two exhaust passages connecting between the two cylinders and opening into the spaces between the valve pistons and the pistons of each assembly, and exhaust passages connecting and opening therefrom for exhausting undistributed fluid returring to the apparatus.

13. A iiuid dispensing system, comprising, a body having a plurality of cylinders therein, eight dual service ports in said body, four of said dual service ports opening into each cylinder, one at each end thereof and one on each side of the center thereof, an inlet port in said body opening into said cylinders to receive fluid under pressure therein, four conduits, each conduit leading from one of the dual service end ports of one cylinder` to one of the dual service ports in the mid-portion o f the other cylinder, piston assemblies in each of saidcylinders operable by the uid under pressure inpassing through the system for reversing the direction of flow of fluid in said conduits, exhaust ports opening from the cylinders for exhausting some of the returned fluid, and a fluid dispensing and by-passing feeder disposed in at least one of said conduits for operation by the fluid passing reversely therethrough.

14. A fluid distributing system comprising, a. body, a plurality of cylinders in substantially parallel relation in said body, each end of each cylinder being internally threaded, the ends of the cylinders having threaded members therein, a plurality of ports opening into each of said cylinders at corresponding similar points, some being adjacent the ends thereof and others being spaced intermediate the ends of the cylinders, conduits connecting the ends of each cylinder into another cylinder, an inlet port in said body for receiving iiuid under pressure therein, conduit means connecting all the cylinders continuously to the inlet port for the iiow of fluid through all the cylinders, a piston assembly in each cylinder arranged to be automatically shifted back and forth by the fluid under pressure, each piston assembly having spaced pistons and intermediate piston valve means so positioned relative to said ports as to alternately connect the ends of the cylinders to iiuid under pressure and to alternately connect the cylinders at their opposite ends to outlets in other cylinders through said conduit means whereby said piston assemblies continuously reciprocate to discharge fluid from opposite ends thereof so long as iiuid under pressure is provided, some of said conduit means consisting of pipes extending externally of said body, fluid dispensing and by-passing feeders connected into some of the external pipes; for operation by the fluid passing reversely therethrough, and exhaust passages connecting between and opening into `the two cylinders into the spaces between the Valve pistons and the pistons on each piston assembly for exhausting fluid therefrom.

EDWIN J. HULL.