US3661055A - Multi-cylinder barrel hydraulic pumps or motors - Google Patents

Multi-cylinder barrel hydraulic pumps or motors Download PDF

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Publication number
US3661055A
US3661055A US40541A US3661055DA US3661055A US 3661055 A US3661055 A US 3661055A US 40541 A US40541 A US 40541A US 3661055D A US3661055D A US 3661055DA US 3661055 A US3661055 A US 3661055A
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United States
Prior art keywords
pump
barrel
valve
bearing
slide face
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Expired - Lifetime
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US40541A
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English (en)
Inventor
Francois C Pruvot
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Automobiles Peugeot SA
Renault SA
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Automobiles Peugeot SA
Renault SA
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F01B3/0044—Component parts, details, e.g. valves, sealings, lubrication
    • F01B3/0064—Machine housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F01B3/0044—Component parts, details, e.g. valves, sealings, lubrication
    • F01B3/0052—Cylinder barrel
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F01B3/0044—Component parts, details, e.g. valves, sealings, lubrication
    • F01B3/0055—Valve means, e.g. valve plate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/0032—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F01B3/0044—Component parts, details, e.g. valves, sealings, lubrication
    • F01B3/007—Swash plate
    • F01B3/0073—Swash plate swash plate bearing means or driving or driven axis bearing means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B3/00—Reciprocating-piston machines or engines with cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F01B3/10—Control of working-fluid admission or discharge peculiar thereto
    • F01B3/103—Control of working-fluid admission or discharge peculiar thereto for machines with rotary cylinder block
    • F01B3/109—Control of working-fluid admission or discharge peculiar thereto for machines with rotary cylinder block by changing the inclination of the axis of the cylinder barrel relative to the swash plate

Definitions

  • PATENTEDMAY 9 I972 3, 661 055 sum 3 OF 3 FIGS FIG.4
  • the present invention relates to hydraulic motors or pumps of the multi-cylinder barrel type having a variable capacity.
  • This invention is directed more particularly to improvements in multi-cylinder barrel pumps of the type broadly mentioned hereinabove, wherein a change in the cylinder capacity is obtained by modifying the angle formed between the barrel axis and the axis of the pump driving shaft, a zero angle corresponding to a zero output or cylinder capacity.
  • the impeller or swash plate rigid with the driving shaft receives the resultant thrust from the pistons which comprises a radial component and an axial component.
  • the plate is not connected directly to the driving shaft and the connecting rods extend at right angles thereto.
  • the axial efiort supported by the multi-barrel body is constant irrespective of the breaking angle since it is dependent only on the assumedly constant pressure, and on the number and diameter of the multiple pistons.
  • impeller or swash plate is balanced by hydrostatic means, but to avoid the inconveniences described hereinabove only a moderate breaking angle was adopted, in order to keep its cosine close to I.
  • the pumps must be driven directly from diesel engines capable of operating at increasingly higher speeds (e.g. 3,000 r.p.m. and more) and high pressures must be resorted to if it is desired to use actuators and pipe lines of reasonable size.
  • the thrust bearings necessary for absorbing the axial stresses on the pump swash plates are not available commercially, and conversely the bearings having a sufficient capacity have a low operating speed, and vice versa. Therefore, pumps must be used wherein the axial forces are balanced hydrostatically, such as the pumps wherein the impeller plate is not coupled to the driving shaft.
  • this type of pump is confronted with so-called in line pumps which are both simpler and smaller in size.
  • this invention is directed to a multi-cylinder barrel pump motor of which the capacity is varied by means of a controlled displacement of the barrel in a support adapted to be inclined in the pump body about a pivot axis perpendicular to the axis of rotation of said barrel, the pistons being provided with ball-headed rods connecting said pistons to an impeller plate rotatably solid, together with said barrel, with the pump driving shaft, said barrel comprising a slide face formed with ports communicating with apertures formed in the cylinder bottoms, said slide face being in rotary contact with the distributing slide face of a distributor plate having formed therethrough two fluid passages each opening into said distributing slide face by means of a crescent-shaped port communicating with suction and delivery ducts of the pump, characterized in that the impeller plate is balanced in the axial direction by a hydrostatic bearing comprising a port registering with the bearing face of said plate in the pump body and corresponding to the delivery port of said distributing slide face, and adapted to be connected to the delivery side of the pump, through the medium
  • This structure is characterized by moderate overall dimensions and permits the construction of very high pressure and high speed pumps having a satisfactory useful life due to the combination of a hydrostatic bearing with the known advantageous features of broken-axis pumps which are essentially the low inertia of rotating parts and the moderate stress supported by moving parts.
  • FIG. I is a sectional view of the pump, the section being taken along the line II of FIG. 2;
  • FIG. 2 is another section taken along the line IIII of FIG.
  • FIG. 3 is a view taken in the direction of the arrows III-III of FIG. 2 showing the distributor plate of the pump;
  • FIG. 4 is a similar view of the barrel, as seen in the direction of the arrows IVIV of FIG. 2;
  • FIG. 5 is a similar view taken in the direction of the arrows V-V of FIG. 2;
  • FIG. 6 is a view taken in the direction of the arrows Vl-VI of FIG. 2, and
  • FIG. 7 is a modified form of embodiment of a detail of the construction shown in FIG. I.
  • the pump comprises a cylindrical rotary barrel in which a number of parallel cylinders 2 disposed on a common concentric circle are formed.
  • This barrel I revolves in babbit or like bearings 3 rigid with a support 4.
  • This support 4 is pivotally mounted in a pump body or outer casing C by means of a pair of pivot faces P formed on the outer race of a rolling-contact bearing R fitted in the casing C; thus, this support 4 can pivot under the action of a control device designated by the reference letter V (FIG.
  • This shaft 8 drives the barrel 1 through the medium of a universal joint comprising a link 9 provided at its ends with driving studs adapted to slide in axial grooves formed on the one hand in said plate and on the other hand in a socket 14 also assembled through splines with said barrel 1.
  • the ball-shaped heads 5 are retained in part-spherical cavities of plate 7 by means of a retainer plate 10 and a spring washer 11 common to all the ball-shaped heads.
  • a spring 12 extending axially in a cavity of the fixed socket 14 of babbit metal or like material holds the barrel 1, in conjunction with the assistance of inner pressures, against the distributor plate 15 secured to the support 4 together with an auxiliary distributor member 25.
  • the socket 14 is held in position by means of the link 9 constituting the barrel driving member.
  • This link 9 is provided with a pair of opposite ball-shaped heads engaging the one a corresponding part-spherical cavity formed in a piston-like member 17 slidably fitted for engagement by a compression spring 12 in the bore of socket 14 and the other a similar cavity formed in a member 19 rigid with plate 7.
  • the distributing slide face 20 of distributor plate 15 engages the slide face 21 of barrel 1 into which open the ports 22 formed in the bottoms of cylinders 2.
  • a pair of crescent-shaped delivery and suction apertures 23, 24 communicate with a pair of holes 23a and 24a respectively, which are formed through the said auxiliary distributor member 25 of which the outer surface constitutes a convex cylindrical slide face 25a.
  • This convex slide face 25a is parallel to a concave cylindrical slide face 26 formed on the inner surface of the cover 27 of pump casing C; as disclosed in the US. Pat. application, 6,7l7, filed on Jan. 29, 1960, now US. Pat. No. 3,589,224, the convex slide face 25a is separated from the concave slide face 26 by an intermediate cylindrical member 28 mounted for rotational sliding movement in the cover 27.
  • the axis of the convex and concave slide faces 25a and 26, as well as the axis of said intermediate member 28, are merged into the pivot axis of support 4. Under these conditions, said member 28 can pivot about this last-mentioned axis.
  • Openings formed in member 28 and receiving tubular members 31 constitute intermediate ducts 34, 35 permitting the communication of holes 230 and 24b respectively with the inlet and outlet ducts 32 and 33 respectively formed in' said cover 27.
  • the intermediate ducts 34 and 35 constantly connect the holes 23a and 24a to the inlet and outlet ducts 32 and 33, respectively, in all the relative positions of assembly 15-25, intermediate member 28 and pump cover 27
  • at least one traction spring shown only diagrammatically at 29 in FIG. 2 connects the casing C to said intermediate member 28 and urges the latter towards a first stop forming portion 37 formed in the casing and a second stop-forming element 38 provided on one end of the convex slide face 25a of said auxiliary distributor member 25.
  • This specific form of embodiment corresponds to a pump with output reversal, this reversal being obtained by moving the barrel from one side to the other side of its zero-capacity position in which it is aligned with the axis of the impeller plate, i.e. when the suction and delivery ducts are inverted.
  • this invention is applicable a fortiori to any similar pump, whether of the output reversal type or not, that is, with a barrel adapted to be inclined on one or both sides of its zero-capacity position.
  • the bearing R retained in the casing C under an end cover 39 is adapted to act as a radial guide to the impeller plate 7 and therefore to the shaft 8.
  • the face 40 of plate 7 bears against a hydrostatic bearing similar to the one formed between the barrel 1 and the distributor plate 15; in other words, this face 40 is formed with distributing cavities 42 identical with those of holes 22 and in this case the cavities 42 are connected through passages 42a to the part spherical recesses receiving the ball-shaped heads 5 in order to ensure the proper lubrication thereof.
  • These cavities 42 register with a pair of ports 43, 44 formed in the cover 39 of casing C, the shape of these ports as seen in plane view in FIG. 6 being identical with that of ports 23, 24; more specifically, the same relationship exists between the holes 22 and apertures 23, 24 on the one hand, as between cavities 42 and ports 43, 44 on the other hand.
  • the ports 43, 44 are furthermore connected to apertures 23, 24 as will be seen presently, are insulated from the low pressure prevailing in the pump casing by a flat land 60, sliding shoes 61 compensating the residual unbalance of the plate.
  • two cylinders 45 each receiving a sliding piston 46 communicate respectively with the pump ducts 32, 33 through holes 47, 50 formed in support 4 and 48, 49 in member 25. These holes 50 are also used for directing lubricating oil to the pivot faces P of support 4.
  • this piston 46 may also co-act with a piston check valve through the intermediary of a ball B as illustrated in FIG. 7, the valve having in this case a flat end face 52c.
  • Ducts 53, 54 and 55 connect the ducts 32, 33 to the corresponding cylinders 51 so that the valves 52 are fed under the same pressure as pistons 46.
  • Each valve 52 is provided with a spool or like seating member 52b adapted to close the inlet orifice of a chamber 56 formed in the cover 39 in alignment with the cylinder 51 for feeding through ducts 57, 58 that port 43, 44 which registers with the delivery port of the pump, which may be port 23 or 24 according to the direction of inclination of the barrel 1.
  • barrel pumps The principle of operation of barrel pumps is well known to those conversant with the art and therefore it is not deemed necessary to describe in detail the specific mode of operation of the pump elements between the driving shaft 8 and the concave slide face 26 of cover 27.
  • the pump output depends on the inclination of barrel 1, supports 4 and distributor plate 15 on either side of the zero-capacity position which is the position in which the axis of rotation of the barrel is coincident with that of the driving shaft, and that on the other hand the fact of passing from one to the other side of this zero-capacity position is attended by the reversal in the direction of flow of the fluid through the ducts 32 and 33 of the pump cover 27.
  • the output decreases and eventually a zero-output condition is attained when the axis of rotation of the barrel is coincident or aligned with that axis of the impeller plate 7. If the barrel support 4 is further pivoted about its axis by actuating its control device V, the abutment or stop portion 38 of distributor member 25 moves the intermediate member 28 until the barrel support 4 is in its endmost position on the right-hand side of FIG. 2.
  • This barrel is balanced in the known fashion, that is, in short, the fluid pressure exerted on the bottoms of the barrel cylinders is substantially balanced by the pressure exerted in the delivery port 23 or 24 and on the auxiliary distributor member 25 in the corresponding intermediate duct 34 or 35.
  • the hydrostatic bearing may consist preferably of sin tered metal and constitute an insert fitted in the casing cover. However, this bearing may also be pressed from a bimetallic bronze-steel plate.
  • connecting rods have not to be formed with bores for directing lubricating oil to the balljoints 5 as usually observed, this constituting a substantial advantage in the case of pumps and motors of very small dimensions.
  • FIG. 1 illustrates a developed view of the pump and it is clear that the holes 54 may lie outside the radial plane containing the pistons 46 in order to reduce the transverse dimensions of the pump.
  • a pump or motor of the multi-cylinder barrel type of which the capacity is adapted to be varied by displacing the barrel in a support adapted to be inclined in the pump body about a pivot axis perpendicular to the axis of rotation of the barrel, the pistons being provided with ball-headed rods positively connecting said pistons to an impeller plate which positively connects the barrel with the pump driving shaft, said barrel comprising a slide face into which open the cylinder ports, said slide face being in rotary contact with a distributing slide face of a distributor plate in which two fluid passages are formed which open each into said distributing slide face through a port having the shape of a sector of an annulus and communicating with suction and delivery ducts of the pump, wherein the impeller plate is balanced axially by a hydrostatic bearing having an alignment with the bearing face of the impeller plate in the pump body at least one port corresponding to the delivery port of said distributing slide face and adapted to be connected to the pump delivery side through a balancing valve which comprises in the barrel support a
  • the pump or motor of claim 1 comprising an impeller plate bearing face having in alignment with the aforesaid port of the pump body, openings corresponding to the aforesaid cylinder ports opening into the barrel slide face.
  • the pump or motor of claim 1 comprising a ball bearing disposed between said control piston and said valve, through which said control piston and valve coact, said ball bearing loosely guided in a recess and bearing against the faees of said piston and said valve which faces are perpendicular to the directions of morement of said piston and said valve, respectively.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Hydraulic Motors (AREA)
US40541A 1969-06-12 1970-05-26 Multi-cylinder barrel hydraulic pumps or motors Expired - Lifetime US3661055A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR6919519A FR2049526A5 (enrdf_load_stackoverflow) 1969-06-12 1969-06-12

Publications (1)

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US3661055A true US3661055A (en) 1972-05-09

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US40541A Expired - Lifetime US3661055A (en) 1969-06-12 1970-05-26 Multi-cylinder barrel hydraulic pumps or motors

Country Status (5)

Country Link
US (1) US3661055A (enrdf_load_stackoverflow)
JP (1) JPS4810722B1 (enrdf_load_stackoverflow)
DE (1) DE2029087C3 (enrdf_load_stackoverflow)
FR (1) FR2049526A5 (enrdf_load_stackoverflow)
GB (1) GB1301525A (enrdf_load_stackoverflow)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3747476A (en) * 1970-03-31 1973-07-24 Delavan Manufacturing Co Balanced hydraulic device
US4024799A (en) * 1974-03-15 1977-05-24 Linde Aktiengesellschaft Axial-piston machine with improved bearing arrangement
US6663354B2 (en) * 2000-11-08 2003-12-16 Linde Aktiengesellschaft Hydrostatic axial piston machine with a control port, a cradle supported swashplate and a swashplate actuating piston
US20130115112A1 (en) * 2010-07-30 2013-05-09 Parker-Hannifin Corporation Variable displacement hydraulic pump/motor with hydrostatic valve plate
US9194381B2 (en) 2012-04-13 2015-11-24 Komatsu Ltd. Bent axis type axial piston pump/motor
US11067100B2 (en) * 2019-05-21 2021-07-20 Danfoss A/S Device for supplying ports to a machine section of a hydraulic machine arrangement
CN115574680A (zh) * 2022-09-30 2023-01-06 海南核电有限公司 一种新型汽动辅助离心泵轴向窜动及磨损测量方法
CN119532239A (zh) * 2025-01-23 2025-02-28 西华大学 一种分段式叶片圆盘泵叶轮及其自动化调节方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5522203Y2 (enrdf_load_stackoverflow) * 1972-06-16 1980-05-27
SE417354B (sv) * 1979-02-23 1981-03-09 Bo Lennart Grelsson Axialkolvpump
DE19833711A1 (de) * 1998-07-27 2000-02-10 Brueninghaus Hydromatik Gmbh Hydrostatische Axialkolbenmaschine mit einer Nachführvorrichtung für eine Zwischenscheibe
CN102926986A (zh) * 2012-11-15 2013-02-13 上海电气液压气动有限公司 一种斜轴式柱塞液压泵后盖
DE102017208755A1 (de) * 2017-05-23 2018-11-29 Danfoss Power Solutions Gmbh & Co. Ohg Hydrostatische unterstützungs- und schmierausnehmungen auf valv- segmentslauffläche
CN110067724B (zh) * 2019-03-13 2024-06-25 上海强田驱动技术有限公司 一种滑盘支承式通轴柱塞泵或马达

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2155455A (en) * 1932-11-24 1939-04-25 Thoma Hans Hydraulic motor and pump
US2298850A (en) * 1939-08-30 1942-10-13 Vickers Inc Pump or motor
FR883348A (fr) * 1942-06-17 1943-07-01 Schlafhorst & Co W Mécanisme de commande à disque oblique
US2455330A (en) * 1942-11-20 1948-11-30 Jr William C Denison Hydraulic apparatus
US2871798A (en) * 1955-12-07 1959-02-03 Thoma Hans Johannes Hydraulic power transmissions
US3208395A (en) * 1963-08-30 1965-09-28 Budzich Tadeusz Cylinder barrel suspension for fluid pressure energy translating device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2155455A (en) * 1932-11-24 1939-04-25 Thoma Hans Hydraulic motor and pump
US2298850A (en) * 1939-08-30 1942-10-13 Vickers Inc Pump or motor
FR883348A (fr) * 1942-06-17 1943-07-01 Schlafhorst & Co W Mécanisme de commande à disque oblique
US2455330A (en) * 1942-11-20 1948-11-30 Jr William C Denison Hydraulic apparatus
US2871798A (en) * 1955-12-07 1959-02-03 Thoma Hans Johannes Hydraulic power transmissions
US3208395A (en) * 1963-08-30 1965-09-28 Budzich Tadeusz Cylinder barrel suspension for fluid pressure energy translating device

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3747476A (en) * 1970-03-31 1973-07-24 Delavan Manufacturing Co Balanced hydraulic device
US4024799A (en) * 1974-03-15 1977-05-24 Linde Aktiengesellschaft Axial-piston machine with improved bearing arrangement
US6663354B2 (en) * 2000-11-08 2003-12-16 Linde Aktiengesellschaft Hydrostatic axial piston machine with a control port, a cradle supported swashplate and a swashplate actuating piston
US20130115112A1 (en) * 2010-07-30 2013-05-09 Parker-Hannifin Corporation Variable displacement hydraulic pump/motor with hydrostatic valve plate
US9194381B2 (en) 2012-04-13 2015-11-24 Komatsu Ltd. Bent axis type axial piston pump/motor
US11067100B2 (en) * 2019-05-21 2021-07-20 Danfoss A/S Device for supplying ports to a machine section of a hydraulic machine arrangement
CN115574680A (zh) * 2022-09-30 2023-01-06 海南核电有限公司 一种新型汽动辅助离心泵轴向窜动及磨损测量方法
CN119532239A (zh) * 2025-01-23 2025-02-28 西华大学 一种分段式叶片圆盘泵叶轮及其自动化调节方法

Also Published As

Publication number Publication date
DE2029087C3 (de) 1975-02-27
DE2029087B2 (de) 1974-07-11
FR2049526A5 (enrdf_load_stackoverflow) 1971-03-26
GB1301525A (enrdf_load_stackoverflow) 1972-12-29
DE2029087A1 (de) 1971-03-18
JPS4810722B1 (enrdf_load_stackoverflow) 1973-04-06

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