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Publication numberUS3601012 A
Publication typeGrant
Publication dateAug 24, 1971
Filing dateMay 21, 1969
Priority dateMay 24, 1968
Publication numberUS 3601012 A, US 3601012A, US-A-3601012, US3601012 A, US3601012A
InventorsOram Harold George
Original AssigneeOram Harold George
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fluid pressure devices
US 3601012 A
Abstract  available in
Images(1)
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Claims  available in
Description  (OCR text may contain errors)

United States Patent [72] lnventor Harold George Oram 285 l-langleton Road, Hove 4, Sesex, England [211 App]. No. 826,504 [22] Filed May 21, 1969 [45] Patented Aug. 24, 1971 [32] Priority May 24, 1968 [33] Great Britain [31 24,951/68 s41 FLUID PRESSURE DEVICES 2 Claims, 1 Drawing Fig.

[52] 11.8. C1 91/499 [51] lnt.Cl F0411 H02 [50] FieldoiSearch 103/162; 230/178; 91/499 [56] References Cited UNITED STATES PATENTS 2,206,305 7/1940 Rose et a1. 103/162 3,007,420 11/1961 Budzich 103/162 3,285,193 11/1966 Jeannin. 103/162 3,295,457 1/1967 Oram 103/162 v FORElGN PATENTS 656,487 6/1961 Great Britain 103/162 713,659 8/1931 France 103/162 Primary ExaminerWilliam L. Freeh Attorney-Cullen, Sloman & Cantor ABSTRACT: The present invention is concerned with fluid pressure pumps or motors of the type having a rotatable cylinder and a plurality of reciprocal pistons which abut a thrust plate inclined to the axis of rotation of the barrel. In order, among other things, to enhance such abutment a fluid pressure device of the invention is so constructed that the barrel is connected to a port plate by a plurality of sleeves in each of which sleeves is reciprocally mounted a said piston. Sealing means are provided between each sleeve and the port plate and in a preferred embodiment'the port plate is associated with a stationary valve plate.

FLUID PRESSURE DEVICES The present invention relates to so-called axial-in-line' fluid pressure devices such as fluid pressure developing units, i.e. pumps, or fluid pressure operated motors.

Such devices generally comprise a rotatable cylinder barrel with a plurality of axial cylinders therein, each cylinder housing a reciprocal piston with a shoe so arranged as to abut a thrust plate which is inclined to the axis of rotation of the cylinder barrel.

It is known that, e.g. when a device of this type is started, it is necessary to bias the cylinder barrel towards a stationary valve plate and to bias the pistons and shoes towards the thrust plate. It isalso known to be necessary to counter the cantilever action of the pistons which tends to tilt the cylinder barrel and cause separation of the cylinder barrel from the valve plate.

In accordance with prior proposals split cylinder barrels have been utilized with pistons reciprocating within the barrel and sleeves connecting the barrel to a port plate. However, such devices are not in all respects satisfactory and it is an object of the present invention to provide a fluid pressure device, e.g. a pump or motor, with means whereby the dynamic response of said port plate is enhanced by the improved maintenance of its abutment with a said valve plate. It is afurther object to provide an economically priced unit, economy folv mounted within each said sleeve and engaging by one of its ends an inclined stationary thrust plate, and sealing means being provided between each said sleeve and the port plate at its region of association therewith;

Advantageously the device comprises a body formed in three parts, the three parts being releasably interengageable by screw means. This, of course, facilitates disassembly.

These and other objects of the invention will be clear from the following description, given with reference to the accompanying drawing which is by way of example and in which there is shown in axial section a fluid pressure device according to the present invention.

Thus there is shown in the drawing a pump or motor of the axialin-line piston type as generally referred to above and as illustrated the pump comprises a body formed from three parts, being a main body part 2, a first cover part 1 and a second cover part 3; the said partsare held together by bolts 23 and 24.

As shown, gaskets 26 are provided between the parts 1, 2 and 3 for the purpose of sealing their abutment surfaces and alignment of the three parts is obtained by locating shoulder screws (not shown). The part 1 is provided with a register diameter and flange for mounting purposes.

A shaft 6, provided with a driving key 21, is supported within the pump body by bearings 16 and 4 circlips 19 and 20 are provided to limit the axial movement of the shaft 6. A suitable seal 5 is provided for sealing purposes. The shaft 6 is also provided with external splines 6a and the said splines engage internal splines formed in a collar 10, a cylinder barrel 11 and a port plate 14. Such engagement is for mutual driving purposes and to achieve alignment between opposing bores 11a and 140 formed in said latter members respectively.

The port plate 14 is also provided with a plurality of arcuate ports 14b which coincide axially with the said bores 14a therein, each said bore 14a receiving a sleeve 12 which is also received as a fit in a said opposing'bore 11a. As shown, each 'sleeve 12 slidably houses a piston 8. As is also shown, the

pistons 8 each have a spherical end 8a onto which'is swaged a shoe 8b, the said shoes 8b being slidable over an inclined stationary thrust plate 7 and constrained by a shoe plate 9 itself biassed by forces exerted by a spring 13 via the cylinder barrel.

1 1, and collar 10. Such biassing results because the member is slidable along the shaft 6 as far as the collar 10.

The thrust plate 7 is suitably located by one or more pins 22 and conveniently, a washer 17 and a circlip 18 are provided to restrict axial movement of all the parts slidably mounted on the shaft 6.

As indicated in the drawing the spring 13 abuts at one end on the cylinder port plate 14 and thus also exerts a force on the said port plate so as to bias it against a valve plate '15 pinned at 15a to the part 3 and so constructed as to comprise two kidney-shaped parts of type well'known in the art. Thus, as a result of such spring biassingthe plate 14 is driven against the plate 15, the barrel 11 is biassed against the collar 10, and the shoe plate 9 is biassed onto the shoes 8b which are slidable on the thrust plate 7. a

As will now be evident, because of the low mass and inertia of the port plate 14, the latter will tend to remain in contact with the valve plate 15, being independent of shaft deflection and barrel movement caused by the cantilever action of the pistons 8 on the inclined thrust plate 7. Furthermore, the sleeves 12 are slidable in the barrel 11, and their fit in plate 14 permits of some flexibility.

By removal of the bolts 23 from the part 1 it will be possible to remove very readily the shaft 6, and all its associated rotatable parts, from the parts 2 and 3.

Various modifications of the invention are, of course, possible within the scope of the invention as defined by the appended claims.

Thus, each sleeve 12, where it extends into the cylinder port plate 14, may be surrounded by a sealing ring.

It will be appreciated that the helical spring 13 may be replaced by a plurality of springs extending in a direction parallel to the axis of the shaft 6.

It will also be appreciated that the collar 10 and the associated spherical or conical bore in the shoe plate 9 are by way of example only and any other suitable assembly may be utilized;

It will also be appreciated that instead of the splines 60 there may be one or more driving keys.

If desired the stationary valve plate 15 may be eliminated and the port plate 14 may bear directly on the cover 3.

I claim What I claim is:

1. A fluid pressure device of the axial-in-line type comprising a cylindrical housing; a first closure member disposed at one end of said housing, a second closure member disposed at the opposite end of said housing; a driven shaft extending axially through said housing rotatably supported in said first and said second closure members; a driven member supported 0 said shaft within said cylindrical housing for rotation with said shaft; a port plate securely attached to said second closure member in sealing engagement therewith; a radially inclined cam plate attached to said first closure member surrounding said shaft; said second closure member having an inlet port and an outlet port; a plurality of communicating ports provided in said port plate communicating with said inlet and said outlet respectively; said driven member having a flange portion provided with a plurality of apertures therethrough in parallel alignment with said shaft; a plurality of sleeve members disposed within said apertures for extension therefrom towards said port plate, each of said sleeve members having a reduced diameter end portion; said port plate being provided with counterbores substantially corresponding in size to said reduced diameter end portions of said sleeves and in axially aligned communication with said ports in said port plate, each of said sleeves being adapted to receive in reciprocable relationship a piston member, the outer end ofsaid piston member being universally attached in radially spaced relationship to a thrust plate surrounding said shaft secured to the driven member; said thrust plate being maintained in frictional engagement against said radially inclined cam plate within said housing so that upon rotation of said shaft within said housing said thrust plate will be forced to rotate along said inclined cam plate to thereby successively reciprocate the plurality of piston members into and out of a respective sleeve associated with said piston member, and resilient expansion means disposed between said driven member and said port plate around said shaft to constantly urge said port plate into engagement against said second closure member for sealing engagement therewith and to urge said driven member into driving engagement against said inclined cam plate.

2. A fluid pressure device of the axial-in-line type comprising a cylindrical housing; a first closure member disposed at one end of said housing, a second closure member disposed at the opposite end of said housing; a driven shaft extending axially through said housing rotatably supported in said first and said second closure members; a driven member supported on said shaft within said cylindrical housing for rotation with said shaft; a port plate securely attached to said second closure member in sealing engagement therewith; a radially inclined cam plate attached to said first closure member surrounding said shaft; said second closure member having an inlet port and an outlet port; a plurality of communicating ports provided in said port plate communicating with said inlet and said outlet respectively; said driven member having a flange portion provided with a plurality of apertures therethrough in parallel alignment with said shaft; a plurality of sleeve members disposed within said apertures for extension therefrom towards said port plate, each of said sleeve members having a reduced diameter end portion; said port plate being provided with counter-bores substantially corresponding in size to said reduced diameter end portions of said sleeves and in axially aligned communication with said ports in said-port plate, each of said sleeves being adapted to receive in reciprocable relationship a piston member, the outer end of said piston member being universally attached in radially spaced relationship to a thrust plate surrounding said shaft secured to the driven member; said thrust plate being maintained in frictional engagement against said radially inclined cam plate within said housing so that upon rotation of said shaft within said housing said thrust plate will be forced to rotate along said inclined cam plate to thereby successively reciprocate the plurality of piston members into and out of a respective sleeve associated with said piston member; resilient expansion means disposed between said driven member and said port plate around said shaft to constantly urge said port plate into engagement against said second closure member for sealing engagement therewith and said driven member into driving engagement against said inclined cam plate; and said port plate and said driven member being coaxially attached to said driven shaft for conjoint rotation therewith by means of splines to thereby maintain said sleeves in parallel aligned relationship with said driven shaft. 1

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2206305 *Apr 28, 1937Jul 2, 1940Waterbury Tool CoPump or motor
US3007420 *Oct 7, 1959Nov 7, 1961Tadeusz BudzichHydraulic pump or motor
US3285193 *Jul 13, 1964Nov 15, 1966Jeannin John FFluid pressure energy translating device
US3295457 *Mar 6, 1964Jan 3, 1967George Oram HaroldFluid pressure developing units
FR713659A * Title not available
GB656487A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3693508 *Dec 28, 1970Sep 26, 1972Sperry Rand CorpPower transmission
US4475871 *Aug 2, 1982Oct 9, 1984Borg-Warner CorporationVariable displacement compressor
US5549032 *Apr 25, 1995Aug 27, 1996Long; Otto V.Low-pollution high-power external combustion engine
US6405634 *Oct 27, 2000Jun 18, 2002Danfoss A/SHydraulic axial piston machine
US7118324 *Aug 4, 2000Oct 10, 2006Luk Fahrzeug-Hydraulik Gmbh & Co. KgCO2 compressor
US7469626Jul 29, 2005Dec 30, 2008Honeywell International, Inc.Split ceramic bore liner, rotor body having a split ceramic bore liner and method of lining a rotor bore with a split ceramic bore liner
DE3233579A1 *Sep 10, 1982Mar 15, 1984Hemscheidt Maschf HermannAxialkolbenmaschine
Classifications
U.S. Classification91/499
International ClassificationF01B3/00
Cooperative ClassificationF01B3/0041, F01B3/0052, F01B3/0064
European ClassificationF01B3/00B4C, F01B3/00B3, F01B3/00B4F