US2545929A - Pump - Google Patents

Description

March Z0, 1951 E. ORSHANSKY, JR n PUMP 8 Sheets-Sheet 1 Original- Filed July 18, 1947 March 20, 1951 E. oRsHANsKY, JR 2,545,929 l PUMP l 8 Sheets-Sheet 2 Original Filed Jul;r 18,y 1947 INVENTUR /'lz'as rsansg, f1:

March 20, 1951 E. oRsHANsKY, JR 2,545,929

PUMP

Original Filed July 18, 1947 8 Sheets-Sheet 5 VIII/,IL

lll/IIL flu lll/III] i IIN@ me #im March 20, 1951 E. oRsHANsKY, JR 2,545,929.

PUMP

Original Filed July 18, 1947 8 Sheets-Sheet 4 March 20, 1951 E, ORSHANSKY, JR 2,545,929

PUMP d OriginalFiled July 18, 194'? 8 'Sheets-Sheet 5 www March 20, 1951 l E; oRsHANsKY, JR 2,545,929

PUMP

Original Filed July 18, 1947 8 Sheets-Shet FROM SUPP! Y UNDER PPE T0 ll/N i INVENTOR. 'as @dd/:slak BY M w/ March 20, 1951 E. oRsHANsKY, .IIR

PUMP

` 8 Sheets-Sheet 7 Original Filed July 18, 1947 INVENToR. z/z'as rsdns/y, fr." BYM( w "in E. ORSHANSKY, JR

March 20, 1951 PUMP 8 Sheets-Sheet 8 maw m H .1.9 md n f.-

.I )K mm Wr Il m L a Sw www W. N T it www, N Mmm im, ,VNJ UTET A@ w ,w Nw fr ...H--- Q is .i L wl .MN .1 -1\. ww H {HIIUL l II 1| I d f f f I Patented Mar. 20, 1951 PUMP Elias: Grsha'nsky; 11i.; Stamford, Conn., assigner to ThefAcrotorque Company, Stamford, Conn., a corporaticnof. Connecticut ContinuationY of application SerialiNo; 761366, July-18,1947. This-application Marchl, 1949,

Serial Nor-84,5232'v 1.9 Claims. lf..

This invention re1ates:to..pumps= and especially to varialcle.- volume lpositive. :displacement pumps ofl the type: inwhichworkin'gf pistons. also per-v form the; function of valvi-ng the fluid .displaced by othery pistons.` This; applioationisl afcontinuation. ofv my z application Serial Number 161,866., ledfilulyrls; 11943.,

An object of this inventionzis: to. provide: apump having an' improved construction and arrange.-

ment. for accomplishinggthe: required resultsV with 2 description of an illustrative embodiment. of the,` invention taken in connection withthe-aecomlpanying drawings in which;

Eig.. l` is. a longitudinal. sectional View vrthroughz a pump'constructed in accordance with one-emi#Y bodinrent of this" invention;

Fig.12V is a transverse sectional view on the line Fig. 3 is a. section on the 'line' 3 3 cfg-Fig. 1;

Fig. 4 is a diagramatic: layoutv of the cylinder block andl pistons, showingzthef methodV of and arrangement for valving the cylinders;

Fig. 5. is1 a. perspective view',v with parts broken away,` lto. showf-the manner of; valvingthe: pump cylinders;

Fig. 6 is an exploded viewof certain wobble disk details.;

Fig. 7 is a longitudinal sectional view similar; to Fig.. '1, showing La pumpof modied construction taken on line 'I-lof Flei;

Fig. v`8A is: a. transverse. cross-sectional :viewfof the constructionof Figi? taken on the 1inef8-'I of Fig-7;

Fig. A9 is: a perspective viewwith parts broken away showing the, 'construction of Fig. .7 and s Fig. lo isa diagrammaticlayoutof the. cylinder block and pistons: showing. the relative positions of the. various' pistons andn their motion..

Ingeneral; the.- invention. comprises av relatively rotatable. shaft and cylinder-.blockin Vwhich axially` extending cylinders. f are arranged `ininterspersedl` pairs; They pistons in; each pair of; cylinders. have rods or. stems extending: outwardly `in opposite idirectionsr, and separate, angularly: aci--Y justable, wobble disksare mounted for rotation by the. shaft for reciprocating the. separate groups ci pistons. Each .cylinder ot.. each .pair has a. pressurev chamberf-porti`on Vand ra valve chain-ber portion. The pressureA chamf-beriof. each cylinder' in eachpair communicates Y.with pump inletf and delivery?.` manifolds through! theyalve chamber portion of the other-cylinder insthepair,` and-each piston Lhasra body portionformed.l to providea slide valvel for controlling the .valving of the adjacent cylinder. Forf properA valvling,l the piston is one of 'each pairofcylindcrs-isdis-1 placedl from the-other o its `pair-lily a 90P phase difference, and this is accomplished by Va suitablel angular mounting of the separate wobbledisks relative.= to eachother. l

The mechanism-by which the wobble-'disks reciprocate the pistons is--such-that the pistons are substantially free of'sidethruston the-cyl inder wallssothatscoring `:from this cause-is substantially eliminated. Volume delivery ofthe puin-p: is varied by simultaneously varying the strokes -of' all pistons,Y andth-is- -isl accomplished by a simple mechanism for simultaneously aflj'usting the angles? of" -theseparate wobble disks relative to theaXis of the supporting shaft- Inf-the drawings,l the-invention isillustrated asl comprising a stationary cylinder block I-I" and rotatable vpurr-1p1shaft' I2I. The `block includes a plurality of pairs of'- cylinder bores-I-3'-, I-4.- Pistons I5l and I are reoiprocablyrn'o1.1ritedl inl eachpair of cylinders I3, I4,.respectiv'ely, and have stemsIT--and t8 extendingoutwardly `in opposite directions.

An annular `housing 2li surrounds the cylinder blockV I IE and -isprovided with a pum-p delivery manifold 22' communicating with annular port 23,*cornmon.to-al1lI purnpcyl-inders I3- and IIL The annular housing also has a pumpv inlet manifold- ZLcQmfm-unicating through Van annular' port v25 in the cylinderl blockwith thewv'alve. chamber portions 25. of thecylinders` l3l`of each'pair, cylinder heads 25 Vbeingy provided in eaclrlcylinder It for closingoit'such .cylindersrfrom the: port 255v and providing pressure-.chambers 2'I Atherein'. A second :pump inletu manifold f 28. is provided` in' the opposite side oi?A the housing ZI .and communi'cates. with the. valve chambers 2li-of cylinders I4 of each pair throughanrannul'ar port13I. inthe cylinder block. Theport .3E is closed olii from the other `cylinders, I3 of each pair by ycyl-- iirder'he'ads 322! which provide pressure: chambers 33 in the. cylinders I3;V

. i 3 With reference to each pair of cylinders (see also Figs 4 and 5), the piston I5 in cylinder I3 alternately connects the inlet manifold 24 and the delivery manifold 22 with the pressure chamber 21 of the adjacent cylinder I4 through a valve passage 34 connecting such pressure chamber 21 with the valve chamber portion 25' of the adjacent cylinder I3. Similarly, the piston IB in the cylinder I4 alternately connects the pressure chamber 33 in the adjacent cylinder I3 with the inlet manifold 28 and the exhaust manifold 22 through a valve passage 34"V connecting the valve chamber portion of cylinder I4 with the pressure chamber 33 of the adjacent cylinder I3.

The piston rods I1 on the group of pistons I5 extend outwardly in one direction, toward the left in Fig. '1, while the rods I8 on the group of pistons I6 extend outwardly in the opposite direction.

A wobble disk 35 is arranged to reciprocate the group of pistons I while a second wobble disk 36 is arranged to reciprocate the other group of pistons I5. Each wobble disk is supported on the pump shaft I2 for rotation therewith and is angularly adjustable thereon to vary the piston stroke of the pump. Each wobble disk comprises a counter-balanced hub 31 pivotally supported on the pump shaft by a pin 38 extending through the shaft and hub. An annular wobble plate 39 is clamped against a positioning shoulder 4G on each hub 31 by a nut 4I and is arranged to reciprocate the associated group of pistons through slidable crossheads of such construction as to substantially prevent the transmission of side thrust to the pistons from the wobble disks. As illustrated, this mechanism includes wear members 42, 43 of partial ball shape having their nat faces frictionally engaging opposite sides of the annular wobble plate 39. These wear members are so formed that their centers of curvature lie in the central plane of the wobble plate 39, The wear members are seated in cup members 44, 45, respectively, which are in turn positioned in a slotted sleeve 46 slidably mounted in a supporting cylinder 41 formed in a wobble plate housing 48 which is secured to one side of the cylinder block II and manifold member 2I so as to enclose the associated wobble disk and piston rods. Ihe wobble plate 4I extends inwardly between the-wear members 42 and 43 through the slotted wall of the sleeve 46, the latter being in line with the associated piston rod. Each cup 44 and 45 has a ange 49 engaging the sleeve on one side of the slot and a spring plate 5i) assists in positioning and holding the c up 44 in the sleeve.

The associated piston I1 is loosely connected to the sleeve 46 to permit a slight radial movement therebetween. This is illustrated as formed by a snap-ring 5I mounted in a groove in the adjacent piston rod and positioned so as to bear against an inner flange 52 in the sleeve 46 on the outward stroke of the piston when the sleeve 5 is drawing the associated piston outwardly. On the inward stroke of the piston the cup member 45 bears against the end of the piston rod. A slight amount of radial play is provided between the `piston I1 and the interior flange 52 and the ring 5I is so dimensioned as to permit such radial play. As a result, it will be apparent that substantially no lateral thrust is applied to the piston. Such lateral thrust as results from operation 'of the wobble disk will be substantially entirely absorbed by the reciprocating sleeve 46 and the supporting housing 48, the engaging surfaces of which can be easily lubricated. The prevention of lateral pressure of the pistons on the cylinder walls renders the pump particularly adapted for the pumping of any fluid which interferes with cylinder wall lubrication.

The housings 48 on each side of the cylinder block rotatably support the pump shaft through ball bearings 54 which are secured to the housings and the pump shaft in any suitable manner.

As best shown in Fig. 6 each wobble disk is counterweighted to balance both the wobble disk itself and also the rotating moment produced by reciprocation of the pistons. Each hub 31 has spaced counterweights 55 formed as part of the hub portion. A separable counterweight member 56 is also mounted on the opposite face of the hub by suitable bolts 51. Both counterweights are slotted to permit angular adjustment of the wobble disk on the pump shaft.

The Volume delivery of the pump is varied by piston stroke adjustment which is in turn accomplished by controlling the angles of the wobble disks relative to the shaft axis. In the present invention a disk-adjusting sleeve 6I is slidably supported on the pump shaft I2 and connected to each wobble' disk hub 31 by a pin 62 mounted in a pin block 63 positioned in a groove 64 of the sleeve 6 I, and engaging openings in the associated hub portion 31 on one side of the pump shaft. The sleeve 6I can be moved longitudinally of the pump shaft by any suitable mechanism such, fol1 example, as a crosshead B6, mounted within the hollow pump shaft and connected to the sleeve 6I by a pin `61 extending through diametrically opposite slots 68 in the shaft. A rod 69 or the like extends outwardly from the crosshead 66 to be actuated in any desired manner. The opposite end of the pump shaft is shown with splines 1I for connection to any suitable source of power.

As heretofore pointed out, in order to provide for proper Valving of the cylinders by the associated pistons, it is necessary that the piston in one cylinder of each pair be displaced from the other piston of that pair by a phase diiference of substantially 96. In other words, in the present invention, one group'of pistons, for example those in cylinders I3, lead the other group of pistons, those in cylinders I4, by a phase diiference of This is accomplished by mounting the wobble disk actuating the first group of pistons in such a way that the supporting pin 38 extends through the pump shaft at the required angle to the pin 33 supporting the other disk. In the illustrated embodiment which shows an 18 cylinder pump, it will be apparent that the cylinders of each pair are 20 apart from each other, therefore the wobble disk actuating the pistons in the cylinders I3, for example, is supported on a pin positioned at an angle of 70 to the pin supporting the other wobble disk, as shown in Fig. l.

Rotation of the pump shaft by a suitable prime mover operates the wobble disks to reciprocate the various pistons, the stroke depending upon the adjustment of the sleeve BI controlling the disk angle. Inward movement of a piston operating crosshead by a wobble disk causes the associated cup member 45 to engage the adjacent end of the piston rod I1 to move it inwardly without transmitting lateral thrust to the associated piston and cylinder wall. Reverse movement of the crosshead moves the cup member 45 out of contact with the piston rod and causes the ange 52 of the slidable sleeve 45 to engage the ring 5I on the piston rod and draw the pisamas-aa ton in the opposite direction: The' 'val-vingof each cylinder is controlled and operated by the reciprocation of they combined' piston-valve in the associated cylinder. The arrangement is suc-h as -to provide the necessary 90?" lead of v one piston by the other. Also,. the associated cylinders are closely adjacent to each other, so. that the Vproper valve Vtiming is obtained without thenecessity of elongated valve passages. between the associated cylinders. The angle-controlling .sleeve 6I is easily yadjusted-by the rodg tovvary the; pump stroke.

The operation and Y valving. isbestz Lillustrated in thediagram of Fig.. 4a Iirthis. diagram each point 12' indicates/thecenter' of the ballforrned by the wearmembers 42,--'43.. at. which` point the reciprocating force vof the wobble` disk is applied to the. associated piston in .line .withv the axis thereof.

The directions of movementA of the various pistons are indicated byV the; arrows` appearing thereon; similarly,V curvedarrows indicate vthe ow of the working fluidilatthe. time indicated.

It will be noted that` four pistons of thegroup designated I5.` are. on their upwardV (intake) stroke. It. will also benoted that at` this time, the fluid is so. valvedby vthe adjacent piston of the other groupv of pistons (l5)v that. iiuid is drawn from they lower manifold 24.

By referring to thoser pistons: .Ie which are on their downward stroke (delivery) it will be noted that the-iiuid displaced thereby is discharged into the manifold 22. It will be noted that fourrof the pistons. I5 are. on their downwardv (intake) stroke and that v.they drawuid from the same manifold 22 to .which the. pistolflsfY i6. deliver their uid..

It will also be noted thatthose pistons I5 which are on their upward (delivery) stroke discharge their fluid into the manifold. 28.. From the above it will be seen that the arrangement is such that a, two stage pump is provided. rihe pistons IB serve to raise the pressure of the fluid from, say, atmospheric to an, intermediate pres'- sure, from which pressure fluid. is taken and the pressure thereof raisedl by means of the pistons .I 5 to approximately double the intermediate pressure.

The form of the invention` shown in Figs.. 7 to 10, inclusive, comprises a 10 cylinderzpump of the single stage variety, in which the volume' of the pump may be varied through hydraulic pressure means. In this form of construction, there are five pistons I5al, I5a2, I5av3, was, and 5a5 which are received in cylinder bores in cylinder block IIa and ve pistons IBai, IGaZ.. iSaS, laad, and i6a5 which operate in bores on the other end of the cylinder block, the pistons of the first group being interspersed .with lthose of the second group and each piston of each group being formed with valve portions which serve to valve the adjacent cylinder of the other group.

Power for operating the pump is applied through the shaft I2a. which is coaxial with. the stationary cylinder block I Ia. The blockv includes a plurality of sets of cylinder bores Isa and Illa within which the pistons a. and 16aare reciprocally mounted, respectively.

Annular housing 2Ia surrounds the cylinder block and is provided with a plurality of annular manifolds LI,HI, L2, and H2. LI and L2 are low pressure manifolds and communicate with each other and with the suction line L3 as indicated schematically at the top of Fig. 7 and in Figs Il). HI Yand Haare4 highpressure manifolds and communicate .with each other-andv with4 they high pressure or delivery manifold line. H3.; The manifold LI communicates through an annular port 25a, in the cylinder block with the. valve chamber portions. 25a in cylinders Isa, cylinder heads 26a .being provided in. cach. cylinder Ida. for closing off such cylinder' from the. port 25a, and providing pressure chambers 21a.v therein. Y

The highpressure manifold H2 communicates through an.V annularA port 25a. with the. valye chambers 29a of cylinders Ilia'. This port'is closed off from theotherV cylinders. I3a bycylinder heads 32a which .provide4 pressure chambers 33mm, cyl,- inders |311.

High pressure manifold HIi communicates throughY a.. port 23a with the valve chamber portionin cylinders. Isa only and low pressure manifold L2 communicates through ports 3 I a .with the valvei chamber portion of .the cylinders.v Ma only.

The pistons are all formed with a. reduced sectionwhich serve as Vpassages for connecting the various ports. at different times. and are formed withconnecting rod ends Ila. and Ida terminating in ball ends I'Ibi and lab respectively.

A- wobble disk 35a isarranged to reciprocate the pistons .i 5w while: a Asecond wobble disk 36a serves to reciprocate the other group. of pistons ia. Each wobble diskis' supported on the pump shaft 52a for rotation therewith, andis angularly adjustable relative to. the. axis. of the. shaft to vary the piston stroke. Each wobble disk comprises a hub Szla pivoted on the pump shaft bya pin 38a, extending.l throughout thee shaft andhub. Said hub has attached thereto. a wobble. plate 39a which carries anouter Vring maand an annular plate Ma. Bearing against the inner face of wobble disk 39a. are. aplurality of shoes da, the shape of which canbest be seen in Fig. 8. One side of each of said shoes is formed vwith a spherical pocket fitting the ball IIb or Ii8b on the, pistons. The. other side of said'balls are contacted by a spherical surface formed on annular rings 43a' which `bear againstv and are slidable upon the plate dla. IThey plates 39a and 4ta are spaced by means of a ring Miu and are clamped inplace by the nut. @5a. A ring 45a. may also be provided, said ring being rctatatrle relative to ring ddd. and. received insuitable cut-away portions on the shoes 42a, and seat rings 43d. It will be noted that ifv the shaft I2ais2rotated with the wobble plates in the. position shown, the pistons will be reciprocated in. their cylinder bores. and that the extent of reciprocation depends upon the angular position of the wobble disk. To reduce friction and wear a lm of oil under pressure is preferably maintained. between thev balls and their seats and also. between the shoes and the wobble plate Sia. This is preferably accomplished by forming the pistons .with axial bores 55m communicating through an opening Sla, in the shoe, which communicates. with suitably formed.V grooves '52aiandf 53a in the flat surface ofthe shoe 42a (Fig. 8").V The axialv bore 500. is intercepted by a vtransverse bore 54a which terminates in a groove 55a in the piston rod. Formed on the outer surface ofthe cylinder block is a groove. 56a. to which oil isv delivered under pressure as'through nipple 51a. It will be noted that when the piston is near the center of its stroke, a passage 58d will align with the groove 55a, thus allowing oil to flow through said various passages to the grooves 52 and 53a and also. to the space between` the balls and their seats.V It will also be noted that the length of time per revolution will vary with the piston stroke. When the pump is operated at a full stroke, the oil supply will be connected to the lu bricating passages only a relatively small part of the time, whereas when the stroke is very small (when high pressures are developed) the lubricating oil is almost constantly in communication. Whereas in the form shown in Figs. l to 6, the adjustment of the wobble disks is effected by means of a sleeve surrounding the operating shaft, the present form accomplishes such adjustment by forming the shaft l2a hollow and providing Within said shaft an axially slidable member to perform this function. This member comprises an adjusting slide Gla which has a slot 62a to receive the wobble disk journal pin 38a and it is also provided with two pins 63a which carry shoes 64a which are slidable within slots 65a in the shaft l2a. Said pins also carry shoes 66a which operate in sloping slots 61a formed in the hub 5ta of the wobble disk. It will be seen, therefore, that axial movement of the adjusting slide 6 la, will cause the wobble disks to be moved about their journal pins 38a and 33a due to the relative angles of the slots 65a and Gla. The slots are so arranged that when the adjusting slide 6|a is moved fully to the left (Fig. 7) both wobble disks will stand at Zero volume, viz: with the wobbley plates 35a at right angles to the pump shaft I2a.

It would appear from Fig. '7 that journal pins 38a and 38a are located 90 from each other. In an actual construction of such a l0 cylinder pump, the pins 38a and 38a are displaced only 54 from each other. of the pistons will be displaced 90 out of phase with the adjacent piston of the other set and, therefore, will be able to serve to valve the fluid moved by such adjacent piston.

While the adjacent slide ila may be moved by hand or other means, it is often desirable to provide hydraulic means for such adjustment. This is accomplished in the present instance by forming the adjusting slide with an extension 64a whi-ch is connected through a ball bearing 'lila with the piston 'lla fitted within a cylinder 12a. Connected to the left end of said cylinder is a port 13a and connected to the right part of said cylinder is a port 14a. These ports lead to a valve cylinder 15a within which is slidably mounted the piston valve member 16a preferably formed generally as shown. Ports 'lla and 18a lead from a conduit 19a which is connected to a drain pipe leading to a sump. Oil under pressure is led to the valve cylinder through a conduit Sca. It will be seen that if the valve piston ita is moved to the right, oil under pressure will be admitted from 80a. through 14a to the rear of the piston Ha causing it to move to the left and therefore reducing the stroke of the pump. During this time the discharge port la is opened to port Tia. This adjusting motion continues until the piston valve 16a, is restored to its central position. If it is now moved to the left the reverse operation will occur, the piston l la will move to the right and the pump stroke will be increased. The operation of this form of pump will be clear from a study of FigflO. The directions of movements of the various pistons are indicated by the arrows appearing thereon; similarly curved arrows show the flow of the working fluid at the time indicated.

It will be noted that two pistons lal and |6055 of the one group are on their upward (intake) stroke. It will also be noted that, at this time, the fluid is so valved by the adjacent piston of the By this arrangement each :n

other group of pistons that fluid is drawn from the intake manifold Ll.

By referring to those pistons |6a3 and I6a4 which are on their downard stroke (delivery) it will be noted that the fiuid displaced thereby is discharged into the delivery manifold HI. It will be noted also that pistons |5112 and l5a3 which are on their downward (intake) stroke are so valved by their adjacent pistons that they draw iuid from the intake manifold L2 and that those pistons |5114 and |5a5 vwhich are on their upward (delivery) stroke are so valved that they discharge fluid into the delivery manifold H2.

As indicated in dotted lines in Figs. 7 and 10, the manifolds Hl and H2 are connected together and to a common delivery manifold H3; similarly the intake manifolds LI and L2 are connected together to a common intake conduit L3. Thus all pistons draw fluid from a common intake and deliver to a common delivery conduit, thus providing a single stage pump.

It is to be noted that, if the manifolds Hl and H2 are not connected together, it will be possible l to deliver two streams of fluid which will be equal in amount if the pistons are all of the same area, or in a different but definite proportion if the pistons of one group have a different area from those of the other group. It is also to be noted that if the inlet manifolds Ll and L2 are not connected together and the discharge manifolds Hl and H2 are not connected together, the pump may be used to pump two independent streams of uid.

Furthermore, the device may be used as a flow divider by supplying liquid under pressure to one pair of manifolds and by having the other manifolds connected to independent circuits. In this event, no external power is applied to or taken from the drive shaft.

While the above description has referred to applicants illustrative embodiments as a pump it is to be understood that it may also be used as an hydraulic motor by supplying to it liuid under pressure through either the manifolds HI and H2 or Ll and L2.

It is intended that the patent shall cover, by suitable expression in the appended claims, whatever features of patentable novelty exist in the mechanism disclosed.

I claim:

l. An hydraulic unit of the positive displacement type comprising a shaft, a plurality of sets of cylinders, the cylinders of one set being interspersed with those of the other set, each cylinder having a pressure chamber and a valve space, pistons reciprocable in said cylinders, each 4piston being shaped to form a valve body movable in the associated valve space, supply manifold means, delivery manifold means, valve passages connecting said manifold means with the pressure chamber of each cylinder through the valve space of an adjacent cylinder, whereby the piston in one cylinder of a set controls the valving of said adjacent cylinder of another set, and means on said shaft for reciprocating the pistons in said adjacent cylinders substantially 90 out of phase.

2. An hydraulic unit comprising a shaft, a pair of cylinders, each having a pressure chamber and a valve space, pistons reciprocable in said cylinders, each forming a valve body movable in the associated valve space, supply manifold means, delivery manifold means, -valve passages connecting said manifold means 'with the pressure chamber in each cylinder through the valve space in the other cylinder, whereby the piston in each .cylinder controls the :valvii-igf-of the-other lcylinder, and a separate wobble disk on ysaid shaft for :actuating .each of said-pistons.

43. An `hydraulic unit comprising a shaft, a pair of cylinders, Aeach :ha-vinga pressure cham- :berand a valve space, pistons reciprocable in said cylinders, .eachforminga valve ibcdy movable in the .associated valve space, supply manifold means, delivery manifold means, valve passages connectingsaid:manifold-means with the pressure chamberin each cylinderlthrough the valve space .in the other cylinder, fwhereby the .piston in each cylinder controls the valving of the other cylinder, separate -Wobblefdisks cnsaid :shaft for ,actuating said pistons, and lmeans :for .supporting said wobble disks .on .said shaft -Lso as to recipro- .cate said pistons substantially .90 ,out of phase.

4. An hydraulicunit comprising fa shaft, a pair of cylinders, each having arpressunechamber and a valve space, pistons :reciprocable in said cylinders, each forming a valve bodymovableinthe associated valve space, .supply :manifold means, .delivery manifold fmeans, valve passages .connecting -said manifold imeans with the lpressure .chamberin each cylinder :through the valve space in the other cylinder, whereby the piston in :each cylinder controls .the valving Vof the other Y.cylinder, separate wobble Adis-ks yonsaid shaft for `actuating said pistons, Vmeansffor supporting said wobble disks on said shaftV so vasto .reciprocate said vpistons substantially .796 .out .of phase, :and means for simultaneously:adjusting theangles of said wobble vlplates for vanyi-ng fthe strokes of A:said pistons.

5. .An-hydraulic uni-t 4of. the positive Vdisplacement type comprising asl-raft, separateg-roups of `axially extending cylinders, pistons in one group of cylinders .having .operating .meanslextending -in one direction, pistons in .another Egroup of cylinders having operating :means extending .in the opposite direction reciprocable in said cylinders, a single Adelivery manifold common to all cylinders, an inlet manifold communicating with the vcylinders associated with one group of pistons, a

secondinlet manifold .communicating with Asaid other cylinders, separate `wobble disks-on said shaft ,for `reciprocating ,each group of pistons, Vand means for simultaneously adjusting .the angle of said wobble ,disksfor varying thestrokes of said pistons. 4

6. An hydraulic unit .comprising .a shaft, a cylinder block having-.a plurality of axial cylinders, pistons reciprocable in said cylinders, alternate groups of pistons having:operating means extending in opposite directions, means onsaid shaft for ,w

reciprocating the pistons having their roperating means extending in one direction, separate means on said shaft for reciprocating the pistons having their operating means extending in the -op posite direction, and mechanismfor simultaneously adjusting said piston reciprocating means, to vary the 'strokes of said pistons of eachlgroup simultaneously. Y

'7. An Vhydraulic unit comprising a sham, .a cylinder block having a plurality of axial cylinders, pistons reciprocable in said cylinders, alternate groups of pistons having operating means extending in opposite directions, means on said shaft for reciprocating the pistons having their operating means extending in one direction, separate means on said shaft for reciprocating the pistons having their operating means extending in the opposite direction, and mechanism movable longitudinally of said shaft for simultaneously adjusting said piston reciprocating means,

vders, a wobble diskvfor reciprocatingsaid pistons,

and means for connecting said disk to said piston rod including `a slidably mounted crosshead in alignment with said rod, means loosely connectingsaid rodt-osaid crosshead, and means for connecting said disk to said crosshead for reciprocationthereby.

:9. .An :hydraulic 4unit com-prising a relatively rotatable shaft `and cylinder block, a piston and `piston rod 'reciprocable in said block, means von fsa-id shaft for reciprocating said piston including .a wobble disk, means for transmitting recipro- -catingfforces from said =disk Ito said piston sub- `s'tantia'llywithout imposing side thrust on said piston, including a Vslidably mounted crosshead 5loosely connected to said piston rod, thrust mem- ?oers in said crosshead on opposite sides of sa-id disk, means connecting one thrust member to said sleeve, said other 'thrust member being adapted to engage the end-of -said piston rod.

10. An hydraulic unit comprising a relatively rotatable shaft land cylinder block, a piston and piston rod reciprocable in said block, means on said shaft for reciprocating said piston including a wobble disk, means for transmitting reciprocating forces `from said disk to said piston substantially Without imposing side thrust on said piston, including a slidably mounted crosshead loosely connected to said piston rod, 'thrust members :in said crosshead on opposite sides of said disk, vhemispherical wear members movably mounted in said thrust member for engagement by vsaid disk, and means yieldingly connecting one 4thrust member to said crosshead, said other thrust member being adapted to `vengage the end of said piston rod.

V1'1. An hydraulicunit comprising a relatively rotatable shaft and cylinder block, a pistonand piston rod reciprocable in said block, means on lsaid 'shaft for reciprocatingv said piston including a wobble disk, means for transmitting reciprocating forces from saiddisk to said piston substantially without imposing side thrust thereon, including a crosshead formed `by a slidably mounted sleeve loosely connected to said piston rod, thrust members mounted in said sleeve engaging opposite sides of said disk, and vmeans yieldingly connecting one. thrust member to ysaid sleeve,said Vother thrust member Vbeing adapted to engage the end 'of said piston rod.

.12. The combination in an hydraulic unit having cylinders 'and pistons, of a shaft, a wobble disk for 'reciprocating said pistonsY including a hub surroundinggsaid shaft and pivoted thereon for angular Iadjustment'relatively thereto, means for adjusting the angular yposition of Said hub including a grooved sleeve vslidably supported on said sha-ft and extending through said hub, a pin mountedV in tliegrocn/e of said 'sleeve and connected to said hub whereby movement of said sleeve longitudinally of said shaft varies the angular adjustment of said wobble disk.

13. An hydraulic unit comprising a pair of cylinders, each having a pressure chamber and a valve space, pistons reciprocable in said cylinders, each piston forming a valve body movable in the associated valve space, a supply manifold, a delivery manifold, valve passages connecting at times said supply manifold with the pressure chamber in one of said cylinders, and, at other times, connecting the said pressure chamber with the delivery manifold, through the valve space in the other cylinder, whereby the piston in each cylinder controls the valving of the other cylinder, operating means for actuating said pistons in such a manner as to reciprocate said pistons substantially 90 out of phase.

14. An hydraulic unit comprising a plurality of pairs of cylinders, each having a pressure chamber and a valve space, pistons reciprocable in said cylinders, each piston forming a valve body movable in the associated valve space, a supply manifold, a delivery manifold, valve passages connecting at times said supply manifold with the pressure chamber in one of said cylinders of a pair, and, at other times, connecting the said pressure chamber with the delivery manifold, through the valve space in the other cylinder of said pair whereby the piston in each cylinder of a pair controls the valving of the other cylinder of said pair, operating means for actuating said pistons in such a manner as to reciprocate the pistons of a pair substantially 90 out of phase.

15. An hydraulic unit comprising a pair of cylinders, each having a pressure chamber and a valve space, pistons reciprocable in said cylinders, each piston forming a valve body movable in the associated valve space, a supply manifold and a delivery manifold for each cylinder of said pair, valve passages connecting at times said supply manifold of one of said pair of cylinders Ywith the pressure chamber in one of said cylinders, and, at other times, connecting the said pressure chamber with the respective delivery manifold through theY valve space in the other cylinder, whereby the piston in each cylinder controls the valving of the other cylinder, operating means for actuating said pistons in such a manner as to reciprocate said pistons substantially'90" out of phase.

16. An hydraulic unit comprising 'a power shaft, a cylinder, a piston reciprocable in said cylinder, operating connections between said shaft 4and said piston including a wobble plate and a shoe slidable on said plate and operatively connected to said piston, and means for delivering lubricant between said relatively slidable shoe and plate comprising a source of pressure for said lubricant, a duct leading therefrom to said cylinder at a point always covered by said piston, a lubricant passage in said piston connecting at one end to the space between said relatively slidable shoe and wobble plate and connecting at the other end to a transverse port in said piston so located that when the piston is in substantially mid-position it aligns with said duct which connects to the pressure source, the said duct and port being so dimensioned that communication between them is interrupted eX- cept when the piston is near mid-stroke.

17. An hydraulic unit comprising a power shaft, a cylinder, a piston reciprocable in said cylinder, operating connections between said shaft and said piston including a wobble plate, a

shoe slidable on said plate, said shoe being formed with a spherical seat in which a ball on said piston seats, and means for delivering lubricant to the space between the plate and the shoe and between the ball and its seat comprising a source of pressure for said lubricant, a duct leading therefrom to said cylinder at a point always covered by said piston, a lubricant passage in said piston connecting at one end to the relatively slidable surfaces between the shoe and the plate and between the shoe and the ball and connecting at the other end to a transverse port in said piston so located that when the piston is in substantially mid-position it aligns with said duct which connects to the pressure source, the said duct and port being so dimensioned that communication between them is interrupted except when the piston is near mid-stroke.

18. An hydraulic unit comprising a power shaft, a cylinder, a piston reciprocable in said cylinder, operating connections between said shaft and said piston including relatively slidable members and means for delivering lubricant to said relatively slidable members comprising a source of pressure for said lubricant, a duct leading therefrom to said cylinder at a point always covered by said piston, a lubricant passage in said piston connecting at one end to said relatively slidable surfaces and connecting at the other end to a transverse port in said piston so located that when the piston is in substantially mid-position it aligns with said duct which connects to the pressure source, the said duct and port being so dimensioned that communication between them is interrupted except when the piston is near mid-stroke.

19. An hydraulic unit comprising a power shaft, a cylinder, a piston reciprocable in said cylinder, operating connections between said shaft and said piston including relatively slidable members and means for delivering lubricantl to said relatively slidable members comprising a source of pressure for said lubricant, a duct leading therefrom to said cylinder at a point always covered by said piston, a lubricant passage in said piston connecting at one end to said relatively slidable surfaces and connecting at tHe other end to a transverse port in said piston so located that when the piston is in substantially mid-position it aligns with said duct which connects to the pressure source.

ELIAS ORS-HANSKY, JR.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 00 1,947,902` DeStoutZ Feb. 20, 1934 1,971,601 Dilg Aug. 28, 1934 2,695,316 Davis Oct. 12, 1937 2,173,856 Orshansky Sept. 26, 1939 2,324,524 Mercier July 20, 1943

Images