US3771423A

US3771423A - Radial pump or motor with stabilized pintle

Info

Publication number: US3771423A
Application number: US00258812A
Authority: US
Inventors: D Culberson
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-06-01
Filing date: 1972-06-01
Publication date: 1973-11-13
Anticipated expiration: 1990-11-13

Abstract

A pintle stabilizer for radial piston pumps or motors adapted to stabilize the ''''blind'''' end of the pintle shaft, i.e., the end remote from the end through which fluids are introduced and discharged. The stabilizer mechanism is characterized by the transmission of pintle stabilizing forces axially through access bores extending through one or more of the segments of the pintle coinciding with a plane directed through the land areas defining the pintle charge and discharge manifolds. The forces transmitted through the access bores are reacted between the remote end of the pintle and a pintle bearing block or the like whereby the tendency of the remote end of the pintle to be deflected in the course of rotation of the cylinder block relative to the pintle is resisted.

Description

United States Patent Culberson Nov. 13, 1973 RADIAL PUMP OR MOTOR WITH STABILIZED PINTLE Primary Examiner-William L. Freeh [75] Inventor: Donald L. Culberson, Teaneck, NJ. AnomeynMal-k Basseches et [73] Assignee: Jaromir Tobias, New York, NY.

[57] ABSTRACT [22] Filed: June 1, 1972 H A pintle stab1l1zer for radial piston pumps or motors PP NOJ 258,812 adapted to stabilize the blind" end of the pintle shaft, Related US Application Data i.e., the end remote from the end through which fluids [63] Continuation of Ser No 119 461 March 1 1971 are introduced and discharged. The stabilizer mechaabandoned' nism is characterized by the transmission of pintle sta- 1 v bilizing forces axially through access bores extending 521 U.S. c1. 91/497, 91 /49s hmugh one mm the segments pintle 511 1m. 01. F01b 1/06 imidlng with f Plane directed the i areas [58] Field of Search 91/197, 198 defimng Pmle charge and dscharge manfolds' The forces transmitted through the access bores are [56] R f s Cit d reacted between the remote end of the pintle and a UNITED STATES PATENTS pintle bearing block or the like whereby the tendency of the remote end of the pintle to be deflected in the 51851223 11132; 13232311;::::..............:::::::::: 311233 Oi rririirrr rriiirr cyiirrrirr iriririr rrirrirrr rrr iirr pintle is resisted. FOREIGN PATENTS OR APPLICATIONS 557,178 2/1957 Italy 91/497 13 Claims 7 Drawing Figures 1 69 as WW6? PAIENIEDunv 13 ms SHEET 1 gr 3 INVENTOR. DONALD L. CULBERSON I "I ORNE) PATENTEDHHY 13 1975 3771.423 SHEET 2 OF 3 INVENTOR. DONALD L. CULBERSON ATTORNEY PATENIEDHUY 13 1915 SHEET 3 BF 3 R O T N E V m DONALD L.CULBERSON ATTORNEY BACKGROUND OF THE INVENTION 1. Field of the Invention This invention is in the field of radial piston pumps and motors and more particularly in the field of mounting means for variable displacement radial piston pumps and motors.

2. The Prior Art Presently, radial piston pumps and motors are in widespread use. Such pumps and motor generally comprise a pintle shaft rotatably supporting a cylinder block. Typically the shaft, generally centrally thereof, is cut away to define diametrically opposed, radially open fluid charge and discharge manifold areas separated by arcuate land portions. A pair of fluid conduits are formed axially of the pintle shaft from one end of the shaft, the conduits each merging with a different one of the manifolds.

The cylinder block is typically provided with an axially directed bore which is so situated that the distal ends of the bore straddle the charge and discharge areas of the pintle shaft and form seals at said straddling position.

The block is provided with a plurality of radially directed cylinders, the innermost ends of which cylinders are provided with passageways extending radially and merging with the bore of the block. As the block is rotated about the shaft, the passageways are progressively scanned across the charge and discharge areas, the passages being sealed during the period that they traverse the arcuate lands separating the areas.

As is well known, pistons are reciprocably mounted in the bores, the pistons being connected to a reaction assembly of any of a variety of types.

The axis of the reaction assembly is offset with respect to the axis of rotation of the block, to provide the necessary degree of eccentricity to assure reciprocation of the pistons.

In pumps and motors of the variable displacement type, means are provided for shifting the axis of the reaction assembly and the block. In addition to varying the displacement by reason of such shifting, it is possible to change the pressure side to the suction side of a pump or the direction of rotation of a motor by shifting the axis of the reaction assembly from one side to the other side of the axis of the block.

The pintle mountings for pumps and motors of the type hereinabove described may be characterized as being of two types. In one type, the pintle is essentially stationary relative to the housing of the pumps or motor and the entire reaction assembly is shifted from side to side relative to the housing, to secure the desired variation in eccentricity. In devices of this type, the pintle is typically straddle mounted, i.e. both ends of the pintle are supported by bearing blocks mechanically connected to the housing. In such straddle mounted pumps and motors, the problem of deflection of the pintle shaft is not significant. Radial pumps and motors of this first type, however, have several disadvantages, including relatively large overall size of the housing to provide clearance for movement of the reaction assembly relative to the housing.

In the second type of radial pump or motor, the reaction assembly does not shift relative to the housing but, rather, variations in eccentricity are effected by moving the pintle shaft carrying the block laterally relative to the housing. Such devices have the advantage of permitting a smaller overall size per unit displacement. However, devices of this second type have heretofore always involved a major disadvantage in that the end of the pintle shaft remote from the fluid input-discharge end (hereinafter referred to as the blind end) is not positively fixed in space to an extent approaching the straddle mounted pintle.

It will be appreciated that the cylinder block with the reciprocating pistons carried therein is essentially an unbalanced load and its rapid rotation subjects the pintle to substantial deflecting forces which tend to urge the pintle axis away from the desired ideal position. Such deflecting forces in the pintle-shiftable types structure have heretofore been resisted solely by connections between the pintle and housing at the input end of the pintle shaft, resulting in a cantilevering of the blind end of the pintle shaft. Such deflecting forces effect a misalignment of the parts with resultant multiple disadvantages, including binding of the parts, accelerated wear, impaired efficiency, noisy operation, vibration, etc.

Additionally, where the pintle is cantilevered, it is necessary to employ a housing of extremely rigid (and hence heavy) construction since the forces developed at the blind end of the pintle are magnified by the fact that such forces are exerted through a considerable leverage arm due to the spacing of the blind end of the pintle from the point of pintle support on the housing.

SUMMARY OF THE INVENTION The present invention may be summarized as directed to an improved pintle mounting for radial piston pumps and motors of the type in which the blind end of the pintle is not accessible for connection to a pintle support fixed in space. In such case, the blind end is provided with a guide support slidingly interconnected with an adjacent bearing block which is stabilized relative to the housing. The connection between the pintle and the bearing block permits lateral movement of the blind end of the pintle relative to the bearing block in a plane extending through and bisecting the land seg ments separating the charge and discharge manifolds of the pintle shaft. It will be appreciated that the sliding connection between the noted parts will be effective to prevent a relative deflection between the blind end of the shaft and the bearing block in a direction normal to the above described plane, but will not be effective to prevent relative movement of the parts within the plane.

Deflections of the latter type are resisted, in accordance with the invention, by interposing between the blind end of the pintle and the bearing block, pintle positioning and stabilizing means variably, mechanically interconnecting the mounting block and the blind end of the pintle.

The pintle is provided with one or more longitudinally extending passageways in areas coinciding with the land segments so as not to interfere with the fluid charge and discharge portions. Force transmitting means extend through the longitudinal passageways into force transmitting relation at the blind end with the piston positioning and stabilizing assembly. The force transmitting means, at the fluid input end of the pintle shaft is connected to sense relative movement between the housing and the input end of the pintle and to drive the stabilizing and positioning means in accordance with the degree of movement sensed, so as to position and stabilize the blind end of the pintle against deflecting movements within the plane above described and extending through the land segments.

As will be readily understood from the several illustrated embodiments, various forms of stabilizing and positioning mechanisms may be employed and various types of force generating and transmitting means may be used to derive power at the fluid input end of the shaft and transmit the same to the positioning means through the longitudinal passageway or passageways.

By way of example, a rotatable rod or drive shaft may extend through the pintle segments. The ends of the rod may be provided with pinions in meshed engagement with racks mounted on the bearing block adjacent the blind end of the pintle and the bearing block adjacent the input end of the pintle. In this embodiment it will be appreciated that when an eccentricity modifying movement is applied to the pintle, the drive rod or shaft will be rotated by reason of the driving connection between the pinion and rack at the input end of the pintle shaft, which movement will be communicated by the rod to the pintle carried at the remote end of the rod, introducing a concomitant movement and stabilization between the blind end of the pintle and the adjacent mounting block.

Other forms of force transmitting means, such as cable connections, threaded connections, hydraulic drives and electrical drives, may be employed to secure the desired shifting and stabilizing of the blind end of the pintle shaft notwithstanding the only access to said blind end is through the body of the pintle.

It is accordingly an object of the invention to provide a radial piston pump or motor including a pintle shaft having a blind end supported for sliding movement within a stabilized mounting block, movable means being interposed between the blind end of the pintle and the mounting block .for stabilizing the pintle, the movable means in turn being powered by force transmitting means extending longitudinally through the pintle shaft.

A further object of the invention is-the provision of a pump or motor of the type described wherein access for force transmission extends through a plane bisecting the land areas of the pintle.

A further object of the invention is the provision of a radial piston or motor having pintle stabilizing means of the type described wherein the stabilizing influence is provided by a cable member arrayed essentially in a plane extending through the land areas of the pintle shaft, the cable being slidably received in axially directed passageways extending through the pintle shaft.

Still a further object of the invention is the provision of a device of the type described wherein a relative light weight housing may be employed owing to the fact that cantilevering of the pintle, with resulting exertion of forces through a magnifying lever arm, is eliminated.

A further object of the invention is the provision of a radial pump or motor including a stabilized pintle of the type described wherein the force transmitting means comprises a rod extending axially and movably through the pintle.

Still a further object of the invention is the provision in a radial piston pump or motor of the type described of a pintle stabilization assembly wherein movement of the pintle relative to the housing varies the displacemerit of one or more hydraulic chambers interposed between the pintle and the housing, there being interposed between the blind end of the piston and the mounting block adjacent the blind end, a comparable variable hydraulic chamber or chambers. Fluid is displaced through lengthwisely extending passages formed in the pintle from the chambers at one end to the other, thereby to stabilize the blind end.

To attain these objects and such further objects as may appear herein or hereinafter pointed out, reference is made to the accompanying drawings, forming a part hereof, in which:

FIG. 1 is a horizontal section through a radial piston pump or motor of the type described, showing one form of piston stabilizing assembly;

FIG. 1a is a fragmentary section, on reduced scale, taken on the line 1a 1a of FIG. 1;

FIG. 2 is a fragmentary section taken on the line 2-2 of FIG. 1;

FIGS. 3 to 6am fragmentary sectional views depicting various forms of pintle stabilizing assemblies, details of construction of related mechanisms, such as the block, cylinders, housing, etc., having been eliminated for purposes of clarity.

Referring now to the drawings, in FIG. 1 there is shown a radial piston pump or motor incorporating a pintle stabilizer mechanism in accordance with the invention. The particular pump or motor shown in FIG. 1 incorporates innovations in the piston operating linkage mechanism, which innovations are the subject matter of an application for patent filed on even date herewith and entitled RADIAL PISTON PUMP OR MOTOR WITH LOW LOSS REACTION LINKAGE. Since the pintle stabilizing apparatus is not limited in its utility to use with pump mechanisms incorporating mechanisms of said co-filed application, the description of the particulars thereof will be limited merely to the extent necessary for an appreciation of the stabilizing mechanism.

In accordance with the invention 10 is a pump or motor housing including an outer end plate 11, which outer end plate is fixed to the annular shoulder 13 defining the outermost end of the housing machine screws 12.

To the plate 11 there is fixedly mounted the outer pintle bearing block 14. The bearing block 14 provides a guiding means permitting movement of the pintle relative to the housing in the direction of the arrow A, FIG. 1. To this end, the block 14 includes an inner plate 15, an outer plate 16, and a spacer place 17 sandwiched between the

plates

15 and 16. The plates are held together by inwardly directed machine screws 18 extending through the plate 16 and threaded into the spacer plate 17. Outwardly directed bolts 19, in similar fashion, extend through apertures in the face plate 11, guide plate 15, and into the spacer plate 17.

The

plates

15, 16 and 17 are provided with registering

apertures

20, 21, 22 which provide clearance for the pintle shaft assembly 23. The aperture 21 in the spacer plate 17 is of larger size than the

apertures

20 and 22 in the

plates

16 and 15, respectively. By this means it will be seen that the

opposed plates

15 and 16 surrounding the aperture define a transversely extending guideway or slot, within which an enlarged collar 24 formed on the pintle shaft is retained. The clearances between the plates and 16 are such as to permit side to side movement of the collar 24.

.As best seen in FIG. la, the upper and

lower surfaces

25, 26 of the collar 24 define parallel guide walls which engage against

complemental walls

27, 28 forming the upper and lower extremities of the aperture 21 in the spacer plate 17. By reason of the engagement of the

walls

25, 27, and 26, 28, respectively, it will be seen that rotative movement of the pintle assembly 23 relative to the housing 10 is prevented while still permitting the desired side to side shifting movement of the pintle.

In FIG. 1 there is diagrammatically disclosed an adjustment mechanism 29 for shifting the pintle relative to the housing in the direction of the arrow A.

A bracket member 30, fixed to the plate 11 as by welding, is provided with an internally threaded bore 31 through which an adjustment screw 32 is threadedly extended. The screw 32 carries an adjustment wheel 33 at its outer end. The lower end 34 of the screw carries an annular drive washer 35, of larger diameter than the screw 32. The pintle 23 carries an annular receiver pocket 36 which rotatably receives the drive washer 35.

From the foregoing it will be appreciated that when the screw 32 is rotated by means of the drive wheel 33, the end 34 of the screw carrying the drive wahser 35 will be shifted (upwardly or downwardly as shown in the orientation of FIG. 1). In view of the washer being received within the pocket 36, threading of the screw will induce a concomitant transverse movement of the pintle 23.

It will be understood that the particular pintle adjusting mechanism hereinabove described in diagrammatic only and that, in practice, any of a series of known adjustment mechanisms which function merely to shift the pintle shaft may be employed.

In the embodiment of FIG. 1, the numeral 40 indicates a reaction assembly including left and right

hand reaction plates

41, 42, respectively which are mounted for rotation within the housing, the plates being connected by a cylindrical reaction shell 43. The left hand reaction plate 41 includes an annular bearing bore 44 having a bearing sleeve 45 rotatably mounted on hollow shaft 46 fixed to the housing.

The housing, at its outer end 47, is provided with a central aperture 48, through which aperture extends an annular bearing support ring 49, the ring 49 forming a mounting for the outer race 50 of the drive shaft bearing 51. The inner race 52 of the bearing rotatably mounts and stabilizes drive shaft 53 relative to the housing.

The right hand reaction plate 42 is fixed to a boss 54 formed on the inner terminal end of the drive shaft 53, as by machine screws 55. The right hand reaction plate 42, on its inwardly directed surface, is provided with a cup-like, cylindrical hollow 56, within which hollow is rotatably mounted the inner pintle slide block or mounting means 57. The mounting means 57 is spaced from the plate 42 by a bearing sleeve 58 or the like, the bearing surfaces between the mounting means and the plate being protected against wear by a hydrostatic bearing assembly operating on oil film fed by fluid under pressure from the hydraulic mechanism, as is well known.

The slide block 57 is provided with a transverse slot 59. The inner end 60 of the pintle assembly 23 is pro vided with a pair of

pins

61, 62 of the same heightwise dimensions as the slot 59, the pins extending into the slot.

From the foregoing it will be observed that the

pins

61, 62 riding in the slot 59, stabilize the blind end 60 of the pintle against movement toward or away from the plane of the view depicted in FIG. 1.

As is best appreciated from FIG. 2, the pintle assembly 23, in the usual manner, is provided with axially directed fluid charge and discharge

conduits

63, 64, the conduits being separated by a central solid segment 65. As is well known, the central portion of the pintle is cut away to define radially outwardly open charge and discharge areas for feeding fluid from the

conduits

63, 64 to the cylinders of a cylinder block as the latter is rotated about the pintle shaft. The outwardly open charge and discharge areas are separated by land portions 66, 67.

In the usual manner, a cylinder block 68 is rotatably mounted over the outwardly open portions of the pintle (identified as the flow area F in FIG. 3). The block includes an internal bore 69 which straddles the flow area F, preventing fluid from passing axially along the surface-of the pintle shaft beyond the flow area.

The cylinder block 68 is provided with a series of radially directed cylinders 70, including flow passages 71 which terminate at the cylinder bore 69. It will be understood that as the block rotates about the pintle shaft, the passages 71 of the various cylinders are sequentially communicated with the charge and discharge areas of the pintle shaft for the interchange of fluid between the cylinders and the pintle shaft. As the cylinders traverse or scan the land areas 66, 67, they are maintained out of communication with either the charge or discharge areas, the land areas thus preventing the flow of fluid across the pintle surface from the high to the low pressure areas.

It will be further appreciated that each cylinder is capped by a piston member 72, which piston members are caused to reciprocate or oscillate axially of their respective pistons by a linkage assembly, referred to generally as 73, which linkage assembly is reacted between the

reaction plates

41, 42 and the pistons.

The reaction assembly and linkage for operating the pistons from the subject matter of my said co-filed application and need not be here described in detail. It should be appreciated, however, that the pintle stabilization device of the present invention may be advantageously employed with conventional radial piston pump and motor assemblies.

From the preceding description it will be understood that the radial piston pump or motor assembly as heretofore described is essentially conventional. The principal advance of the present invention is considered to reside in the stabilization concept next to be described, whereby stabilization of the blind end 60 of the pintle against movement upwardly or downwardly when viewed in the orientation of FIG. 1 is achieved.

It will be recalled that the interengagement of the

pins

61, 62 in the slot 59 essentially prevents deflecting movement of the blind end 60 of the pintle in any direction except in the direction of a plane aligned with the slot 59. It is a function of the stabilization mechanism to prevent or stabilize the blind end of the pintle against deflected movements of the blind end within such plane.

For purposes of facilitating understanding, it should be appreciated that the plane in which deflecting movement is sought to be prevented extends through the axis of the pintle and is parallel with the walls defining the slot 59 and the

walls

27, 28 formed in the spacer plate 17. It has been determined that the terminal deflecting forces to which the blind end of the pintle is subjected lie in the plane above described, which plane also bisects the segment 65 and the land areas 66, 67.

In the form of pintle stabilization apparatus shown in FIGS. 1 and 2, the stabilizing function is served by one or more cable assemblies 80, the distal ends 81, 82 of which are fixed against movement with respect to the housing by being secured to the housing or to the outer mounting block 14. The pintle is provided with a pair of axially extending

passageways

83, 84, open at the inner or blind end 60 of the pintle. As will be seen, the

passageways

83, 84 are formed in the solid segment which separates the charge and discharge conduits in the pintle shaft. In order to facilitate a sliding movement of the cable relative to the pintle,

rounded transition portions

85, 86 are formed in the pintle leading to the

passageways

83, 84.

The cable 80 includes axially directed

branches

87, 88, slidably received in the

passages

83, 84, respectively, and includes an inner transverse portion 89 externally of the inner or blind end of the pintle shaft. The transverse portion 89 of the cable is fixed, as at the point 90, to the inner mounting means 57. Optionally but preferably, the transition portions of the cable beteeen the transverse portion 89 and the

axially extending portions

87, 88 are led over idler pulleys 91, 92. The block 57 is, of course, provided with a clearance area 93 to provide room for the transverse movement of the pulleys and cable portions relative to the block.

It will be understood that the heightwise extent or thickness of the

pins

61, 62 and the slot 59 is sufficiently greater than the heightwise dimension of the pulleys and cable to permit the above noted relative movement without losing the guiding function previously described between said pins and slot.

From the foregoing description it will be evident that as the pintle shaft is bodily shifted through the use of the adjustment mechanism 29, one or the other of the

branches

81, 82 will become elongated, the other said branch being foreshortened in an amount corresponding to the amount which the pintle has been displaced.

In the above described embodiment, the cable assembly 80 is divided into two branches, notably the branch running from the distal end 82 to the anchor point 90, and the branch running from the distal end 81 to'the anchor point 90. As the pintle is shifted upwardly or downwardly, as viewed in FIG. 1, it will be appreciated that if the length of the portion 81 is foreshortened by reason of a downward movement of the pintle, there will be a concomitant increase in the length of the transverse portion 89 of the cable which forms a part of the lower branch 88. In similar fashion and again presuming a downward movement of the pintle as viewed in FIG. 1, the length of the portion 82 of the upper branch 87 will be increased and the portion of the transverse branch 89 above the anchor point 90 will be decreased by an equal amount.

It will thus be seen that the two

branches

87, 88 will always remain the same length and that a side to side movement of the pintle will result in an axial movement of portions of the branches of the cable within the pintle shaft.

' Although in the embodiment of FIGS. 1 and 2 a single continuous cable is shown, it will be readily recognized that two separate cables arrayed in an X configuration and forming the mechanical equivalent of the single cable may be advantageously employed, especially in a unit where large transverse movements are required. In such modification, each separate cable branch will include a transverse portion adjacent the blind end of the pintle, the transverse portions crossing with the end of the upper branch 87 being fixed to the block 57 adjacent the lower end thereof, and the end of the lower branch 88 fixed to the upper end of the block 57.

It will be evident from the above description that the cable, which is maintained under tension, will firmly stabilize the blind end of the pintle against any tendency toward deflection within the previously described plane extending through the central segment of the pintle shaft.

It will be observed that, although the pintle is not straddle mounted and there is no direct stabilizing of the inner end of the pintle by access through the drive shaft end of the assembly, the above described arrangement results in the development of stabilizing forces when the pintle is shifted relative to the housing, which forces are transmitted through the length ofthe pintle and reacted between the pintle and the inner bearing block 57 which is fixed in space relative to the housing. Thus, the invention, in its broadest sense, contemplates development of mechanical stabilizing forces responsive to movement of the pintle, the transmission of such mechanical forces longitudinally of the pintle shaft, and most particularly through the solid segment dividing the pintle, and the reaction of the forces thus developed between an inner bearing means fixed in space and the inner blind end of the pintle shaft. Numerous other embodiments employing the general principle above set out may be readily envisioned in the light of the foregoing teachings.

In FIGS. 3 to 6, by way of example, in which like parts have been given like reference numerals, there are shown four additional embodiments.

In the embodiment of FIG. 3, the adjustment mechanism 29 includes at the innermost end of the adjustment screw 32 a bevel gear 100. An adjustment drive shaft 101 extends axially through the pintle shaft assembly 23. The drive shaft 101 includes a bevel gear 102 in driving relation with the gear 100, the shaft 101 including at its other end a further bevel gear 103.

The inner guide block 57 is, in this embodiment, provided with a bracket 104 having an internally threaded aperture 105. In this case, the stabilizing and adjusting function of the blind end 60 of the pintle shaft is provided by a threaded rod 106 which is threadedly interfitted with the aperture 105 of the bracket 104. The rod 106 carries a further bevel gear 107 meshed with the gear 103 at the inner end of the drive rod 101.

From the foregoing it will be observed that rotation of the adjustment screw 32 through the meshing bevel gears and 102 will rotate the rod 101. The rotation of the rod 101 will, in turn,-through the mating gears 103 and 107, rotate the threaded rod 106 the same number of rotations as are applied to the adjustment screw 32. Since the threads of the

screws

32 and 106 are of the same pitch, it will be appreciated that the inner end 60 of the pintle will be shifted a distance and direction to maintain the pintle shaft axis in parallelism with the axis of rotation of the reaction assembly. Additionally, forces which tend to displace the pintle axis will be resisted by the threaded engagement of the threaded rod 106 and the bracket 104 forming a part of the fixedly positioned guide means 56. In this manner it will be observed that the rod 106 and the bracket 104 function as a pintle positioning and stabilizing means powered by rotation of the rod 101.

In the embodiment of FIG. 4, a rack member 108 is fixed to the housing, a comparable rack 109 being formed in the inner mounting means of guide block 57. In this instance, a pair of pinion gears 110 and 111 are fixed at the opposite ends of the drive shaft 101. It will be observed in connection with this embodiment that as the pintle is shifted, the engagement of the pinion 111 with the rack 108 will cause a rotation of the shaft 101 and that such rotation will cause the pinion 110 to advance along the rack 109 to the same degree as the pinion 111 has advanced across the rack 108.

By this arrangement, power is transmitted through the pintle shaft by the drive shaft 101 and forces developed by engagement of the outer pinion 111 with the outer rack 108 drive the inner pinion over the rack 109 so that the last mentioned two parts operate as positioning and stabilizing means for the inner or blind end 60 of the pintle.

In the embodiment of FIG. 5, a chain member 112 extends through the solid segment portion of the pintle assembly 23, the chain being in driving connection with a sprocket 113 affixed to threaded cross rod 114. The threaded cross rod 114 passes through a threaded bracket 115 fixed to the inner guide block or mounting means 57. The chain is driven by a sprocket 116 connected to the adjustment screw 32 so that rotation of the adjustment screw will, through the sprocket 116, drive the chain 112, movement of the chain in turn being effective, through the connection with sprocket 113, to rotate the threaded cross rod l14.

By reason of the threaded interengagement between the rod 114 and the bracket 115, the blind end 60 of the embodiment of FIG. will be caused to move transversely in accordance with the adjustment of the outer end of the pintle, the inner end being stabilized in its adjusted position by the threaded interconnection between the block 57 and the rod 114 above described.

In the embodiment of FIG: 6, the stabilizing forces are effected by hydraulic means, there being provided one or more closed hydraulic circuits, each such circuit inlcuding variable displacement chambers at the input end of the pintle and a connected chamber interposed between the blind end of the pintle and the mounting

members

120, 121, respectively. Hydraulic piston 122 is sealingly received in the upper chamber 120, the piston being made fast at its outer end 123 to bracket 124 forming a part of the adjustment assembly and fixed in respect to the housing. In similar fashion, a lower piston 125 is sealingly and slidably disposed within cylinder 121, the piston being made fast by bracket 126, which is likewise fixed against movement relative to the hous- It will be appreciated that the

cylinders

120, 121 define variable displacement chambers and that any transverse movement of the pintle shaft will increase the capacity of one chamber and decrease the capacity of the other, depending upon the direction of movement. The pintle is provided with axially extending

passages

127, 128 communicating with the

chambers

120, 121, respectively.

A reaction post 129 extends from the blind end 60 of the pintle through the slot 59 thereon. A pair of diam etrically opposed, outwardly directed

piston members

130, 131 are secured to the innermost end of the post 129, the axes of the

pistons

130, 131 being aligned with the plane of movement of the pintle. A pair of

cylinder members

132, 133 are fixed, as by welding, to the interior of the mounting block, the

pistons

130, 131 being slidingly engaged within the bores of the

cylinders

132, 133, respectively.

Flexible connector hoses

134, 135 are connected between the conduit 127 and the cylinder 133, and the conduit 128 and the cylinder 132, respectively. The displacement of the piston and cylinder of any one hydraulic system is, of course, identical.

From the foregoing it will be observed that if the pintle shaft is shifted upwardly, when viewed in the direction of FIG. 6, fluid will be displaced from the chamber 120 through the conduit 127 and into the cylinder 133, forcing a concomitant upward movement of the piston 131, resulting in an equal upward movement of the blind end 60. Fluid which has been displaced from the cylinder 132, through connector hose 135 and conduit 128, enters into the cylinder 121 of the pintle shaft. It will be readily recognized that the flow in the various conduits will be in opposite directions in the event that the pintle 23 is shifted downwardly.

From the foregoing it will be evident that there are provided a plurality of embodiments operating on the common concept of providing mounting means for the pintle of a radial piston pump or motor wherein movement of one end of the pintle results in a concomitant movement and stabilization of the other end of the pintle, the movement and stabilization being effected responsive to forces generated at the input end of the pintle and transmitted longitudinally through the pintle.

It will be readily recognized that a variety of mechanical expedients may be used to generate and to transmit the forces required to achieve the desired result.

It will be further understood that by stabilizing the blind end of the pintle without requiring access thereto through the housing portion closest to the blind end, the ability to extract power and effect a torque transmitting connection between the drive shaft and the reaction assembly or cylinder block is greatly facilitated.

It is to be understood that the present invention is not to be limited to the specific embodiments shown but, rather, is to be broadly interpreted within the scope of the appended claims.

Having thus described the invention and illustrated its use, what is claimed as new and is desired to be secured by Letters Patent is:

l. A radial piston pump ormotor including a housing, a reaction assembly carried by said housing for rotation about a fixed axis, a cylindrical pintle shaft within said housing recessed to define outwardly open fluid charge and discharge areas separated by diametrically opposed solid segments terminating in arcuate land areas, said pintle including a fluid input end and a blind end, a cylinder block having a central bore straddling said charge and discharge areas, and rotatably mounting said block on said shaft, first and second mounting means engaging said input and blind ends, respectively, of said shaft, said mounting means being fixed in position relative to said housing and including guide means slidably engaging said ends of said shaft for guiding said shaft for bodily movement relative to said housing in a plane bisecting said segments, adjustment means interposed between said housing and said input end of said shaft for shifting said input end relative to said first mounting means in said plane, drive means extending axially of said shaft through at least one of said segments, said drive means being shifted relative to said shaft responsive to the movement of said shaft relative to said first mounting means, and pintle positioning and stabilization means interposed between said blind end of said shaft and reacting against having said and operated responsive to movement of said drive means for shifting and stabilizing said blind end relative to said second mounting means in accordance with the movement of said drive means relative to said shaft.

2. The device of claim 1 and including a torque transmission drive shaft extending through said housing at the end nearest said blind end of said shaft.

3. The device of claim 2 wherein said transmission drive shaft is operatively connected to said reaction assembly.

4. The device of claim 1 wherein said shaft includes a pair of axially extending guideway channels extending through said segments, and said drive means comprises a cable assembly arrayed in a configuration coincident with said plane, the ends of said cable being fixed with respect to said housing adjacent said first mounting means, said cable including two branches, each having an axially extending length slidably received in said channels, and a transverse portion at the end of said length adjacent said second mounting means, said transverse portions being fixed to said second mounting means whereby the effective length of one said branch is elongated and that of the other said branch foreshortened in equal amounts responsive to movement in said plane of said input end of said shaft relative to said housing.

5. The device of claim 4 wherein said cable assembly comprises a single cable and said transverse portion includes a central connection fixed to said second mounting means.

6. The device of claim 4 wherein said cable assembly includes first and second independent cable portions arrayed in an essentially X" configuration.

7. the device of claim 1 wherein said drive means comprises a drive shaft rotatably mounted in said pintle, the distal ends of said drive shaft being located at the input end and the blind end of said pintle shaft, drive shaft operating means reacted between said housing and the end of said drive shaft at said input end for rotating said drive shaft an amount proportional to the amount of movement of said pintle shaft relative to said housing, the other end ofsaid drive shaft being drivingly connected to said pintle positioning and stabilizing means.

8. The device of claim 7 wherein said adjustment means and said positioning and stabilizing means each comprises threaded connector members, and said drive shaft is operatively associated with both said connector members to. rotate one said connector in accordance with the rotation of the other.

9. The device of claim 7 wherein said adjustment means and said positioning and stabilizing means each comprises rack members on said mounting means and said drive shaft includes pinion gears in meshed relation with said rack members.

10. A device in accordance with claim 1 wherein said drive means comprises a chain member drivingly linking said adjustment and said shifting and stabilization means.

11. A device in accordance with claim 1 wherein said drive means comprises a closed hydraulic circuit of fixed capacity and said shifting and stabilization means comprises a variable displacement hydraulic piston and cylinder assembly adapted to reciprocate in said direction of said plane, said circuit including a second hydraulic piston and cylinder assembly reciprocable in said direction interposed between said pintle shaft and housing, said piston and cylinder assemblies being of equal cross section and disposed at opposite sides of said shaft whereby, upon shifting movement of said pintle shaft, the volume of fluid driven from one said piston and cylinder assembly enters into the other.

12. A radial piston pump or motor including a housing, a reaction assembly carried by said housing for rotation about a fixed axis, a cylindrical pintle shaft within said housing recessed to define outwardly open fluid charge and discharge areas separated by diametrically opposed solid segments terminating in arcuate land areas, said pintle including a fluid input end and a blind end, a cylinder block having a central bore straddling said charge and discharge areas, and rotatably mounting said block on said shaft, first and second mounting means engaging said input and blind ends, respectively, of said shaft, said mounting means being fixed in position relative to said housing and including guide means slidably engaging said ends of said shaft for guiding said shaft for bodily movement relative to said housing in a plane bisecting said segments, adjustment means interposed between said housing and said input end of said shaft for shifting said input end relative to said first mounting means in said plane, sensing means for determining the position of said output end of said shaft relative to said first mounting means, force conduit means extending lengthwisely of said shaft through at least one of said segments for transmitting forces through said shaft in accordance with the position sensed by said sensing means, motor means interposed between said blind end of said shaft and reacting against housing means powered by the forces transmitted through said conduit means for shifting said blind end relative to said second mounting means to maintain the axis of said shaft parallel with the axis of said reaction assembly.

13. The device of claim 12 wherein said conduit means comprises a fluid flow path, and said sensing means and motor means comprise variable displacement hydraulic piston and cylinder assemblies.

Claims

1. A radial piston pump or motor including a housing, a reaction assembly carried by said housing for rotation about a fixed axis, a cylindrical pintle shaft within said housing recessed to define outwardly open fluid charge and discharge areas separated by diametrically opposed solid segments terminating in arcuate land areas, said pintle including a fluid input end and a blind end, a cylinder block having a central bore straddling said charge and discharge areas, and rotatably mounting said block on said shaft, first and second mounting means engaging said input and blind ends, respectively, of said shaft, said mounting means being fixed in position relative to said housing and including guide means slidably engaging said ends of said shaft for guiding said shaft for bodily movement relative to said housing in a plane bisecting said segments, adjustment means interposed between said housing and said input end of said shaft for shifting said input end relative to said first mounting means in said plane, drive means extending axially of said shaft through at least one of said segments, said drive means being shifted relative to said shaft responsive to the movement of said shaft relative to said first mounting means, and pintle positioning and stabilization means interposed between said blind end of said shaft and reacting against having said and operated responsive to movement of said drive means for shifting and stabilizing said blind end relative to said second mounting means in accordance with the movement of said drive means relative to said shaft.

6. The device of claim 4 wherein said cable assembly includes first and second independent cable portions arrayed in an essentially ''''X'''' configuration.

7. the device of claim 1 wherein said drive means comprises a drive shaft rotatably mounted in said pintle, the distal ends of said drive shaft being located at the input end and the blind end of said pintle shaft, drive shaft operating means reacted between said housing and the end of said drive shaft at said input end for rotating said drive shaft an amount proportional to the amount of movement of said pintle shaft relative to said housing, the other end of said drive shaft being drivingly connected to said pintle positioning and stabilizing means.

8. The device of claim 7 wherein said adjustment means and said positioning and stabilizing means each comprises threaded connector members, and said drive shaft is operatively associated with both said connector members to rotate one said connector in accordance with the rotation of the other.