US3887308A - Valve porting arrangement for a gerotor - Google Patents

Valve porting arrangement for a gerotor Download PDF

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Publication number
US3887308A
US3887308A US355411A US35541173A US3887308A US 3887308 A US3887308 A US 3887308A US 355411 A US355411 A US 355411A US 35541173 A US35541173 A US 35541173A US 3887308 A US3887308 A US 3887308A
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US
United States
Prior art keywords
controlling member
combination
flow
internal gear
gear
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US355411A
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English (en)
Inventor
Karl-Heinz Liebert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ZF Friedrichshafen AG
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ZF Friedrichshafen AG
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Publication date
Application filed by ZF Friedrichshafen AG filed Critical ZF Friedrichshafen AG
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Publication of US3887308A publication Critical patent/US3887308A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2/00—Rotary-piston machines or pumps
    • F04C2/08—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C2/10—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member
    • F04C2/103—Rotary-piston machines or pumps of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member one member having simultaneously a rotational movement about its own axis and an orbital movement
    • F04C2/105—Details concerning timing or distribution valves
    • F04C2/106—Spool type distribution valves
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/86638—Rotary valve
    • Y10T137/86646—Plug type
    • Y10T137/86662—Axial and radial flow

Definitions

  • PATENTEDJUH 3 ms SHEET FIGZ PATENTEDJUH .975 v .887.308
  • This invention relates to a hydrostatic pump or fluid motor, particularly useful in hydrostatic power steering systems for motor vehicles.
  • Fluid displacing devices having a fixed toothed ring with an internal tooth profile and an external gear having one tooth less than said ring so as to produce a planetary movement of an external gear, are well known.
  • a fluid distributing arrangement is generally rotatable with the external gear about its axis and includes a control valve having channels leading to each fluid pressure chamber formed between the teeth of the tooth ring. Control openings corresponding in number to twice the number of teeth of the toothed ring are disposed in the housing for cooperation with said channels.
  • the fluid distributing arrangement alternately establishes fluid communication between the pressure chambers and separate fluid conduits conducting fluid medium to and from the fluid displacement device.
  • Such rotary fluid displacing devices with a rotating distributor control valve deliver a relatively large mass of fluid per rotation of the driving shaft at a low speed, in the case ofa pump operation, or in the case of motor operation, a relatively large driven torque and fluid absorption volume for a low driven speed.
  • Such devices are therefore used in hydrostatic steering systems for motor vehicles as a hydraulic auxiliary power assist under control of the steering wheel or as a hydraulic auxiliary power source operable by the steering wheel.
  • fluid pressure channels are formed in the gear and lead to gaps between the teeth and to openings in fixed walls of the housing forming part of a fluid distribution system, so that movement of the gear around its center by one tooth pitch, completes a control cycle of the distribution system.
  • a cylindrical rotating slide valve rotating with the driving or driven shaft in coaxial relation thereto has longitudinal grooves on its outside cylindrical surface, which are alternately connected with separate pressure lines, and to channels leading to the pressure chambers formed between the teeth of the internally toothed ring.
  • a rotary piston is mounted in a housing, the cross section of which constitutes a triangle with rounded corners and connected by means of a drive shaft with the driving or driven shaft, so that the rotary piston upon one turn of the shaft by 360 rotates a number of times about its center, corresponding to the number of teeth of the rotary piston, as it travels along a circular path around the axis of the housing, in a direction opposite to the rotational direction of the shaft.
  • discharge of the operating medium is controlled by cooperation between control channels in one surface of the rotary piston and a number of control openings arranged in a wall of the housing adjacent to said channels, as a result of which said openings alternately communicate with the control channels of the rotary piston.
  • the gear is connected with the main shaft by means of a drive shaft, so that the cylindrical, rotary slide of the distributor at the rotational speed of the main shaft and coaxial therewith, rotates synchronously with the rotational movement of the piston about its own axis.
  • the rotary slide at the same time has a number of longitudinal grooves corresponding to double the number of teeth of the gear, which are connected in an alternating sequence each time with a separate pressure line and cooperate with channels disposed in the housing leading to the root of the teeth of the toothed ring.
  • an important object of the present invention is to provide a rotary piston engine with rotating distributor control, wherein an optimum degree of filling is effected with small losses of pressure in the supply channels conducting flow to the pressure medium operating chambers formed between the toothed profiles of the external gear and the internally toothed ring.
  • the invention includes a rotary slide, rotatable with the external gear which in turn is coupled in a manner known to the driving shaft by means of coupling shaft.
  • the rotary slide is connected slidingly at one axial end with a surface of the gear and has longitudinal grooves extending axially on its radially outer or outside cylindrical sur face communicating on said one axial end with the gaps between the teeth of the gear.
  • the grooves are also axially aligned with control openings in the housing to provide alternating fluid communication with separate pressure lines along the cylindrical surface.
  • the longitudinal grooves disposed on the outside surface of the rotary slide have enlargements at the ends in a sliding contact with one axial surface of the gear to advantageously conduct flow between the operating chambers and the inflow and outflow ports with a minimal amount of throttling.
  • FIG. 1 shows a longitudinal section view through a rotary piston engine constructed in accordance to the present invention.
  • FIGS. 26 are transverse section views taken through planes indicated by section lines lI-II, lII--III, IVIV, V-V and VI-VI of FIG. 1.
  • FIG. 8 shows a modified form of the rotary piston engine constructed in accordance to the present invention.
  • FIG. 7 is a side elevation view of the rotary slide.
  • An internal toothed ring or gear 1 as shown in FIG. 1, is disposed between an end cover 2 and a housing body 3 to which it is fixed by means of screws 4.
  • An externally toothed gear 5 having one tooth less than the toothed ring 1, forms with said toothed ring 1 operating chambers 6 radially between the teeth of the two gears and axially between the confronting surfaces of the cover wall 2 and the housing 3.
  • the gear 5 is connected for rotation with a driving shaft 8 by means of a coupling shaft 7.
  • Two driver pins 9 and and the coupling shaft 7 fonn a universal, articulated connection between the gear 5 and the driving shaft 8.
  • the coupling shaft 7 is fixed in an axial direction in the driving shaft 8 by a front surface 11 and in the gear 5 by a buffer disk 12 abutting the cover wall 2.
  • a flow controlling member in the form of a rotary slide 13 is coaxially mounted relative to the driving shaft 8 in the housing 3 and coupled to the driving shaft 8 by means of a coupling pin 14 for rotation therewith.
  • a coupling pin 14 for rotation therewith.
  • the rotary slide 13 could be made an integral component of the driving shaft 8 as shown in FIG. 8 to avoid misalignment.
  • the gear 5 is coupled to the driving shaft 8 as aforementioned so that upon each revolution of the driving shaft 8, the gear 5 will rotate about its own axis in a reverse direction a number of revolutions corresponding to the relative numbers of teeth of the gear 5 and ring 1, as the gear 5 is carried in a circular path about the axis of the fixed toothed ring 1.
  • Longitudinal grooves 17, leading to the gaps between the teeth of the gear 5, are formed on the outside cylindrical valve surface of the rotary slide 13.
  • the longitudinal grooves 17 have enlargements 18 on the front axial end surface of the rotary slide 13 adjacent to the gear 5, to enlarge the transitional flow area to the operating chambers 6. Since both the rotary slide 13 as well as the gear 5 are rotatably coupled to the driving shaft 8, and the gear 5 planetates in a direction opposite to the rotary movement of the driving shaft, during expansion and contraction of the volume of the operating chamber 6 there is relative displacement between the rotary slide 13 and the gear 5 in synchronism with the rotational movements.
  • the longitudinal grooves 17 are axially aligned with control openings 21 or 22 formed in the housing 3 as shown in FIGS. 4 and 5 so that the grooves 17 communicate alternately with separate ports 19 or 20 for the inflow or the return flow of a fluid pressure medium.
  • the number of control openings 21 and 22 correspond to double the number of teeth of the toothed ring 1.
  • the control openings 21 or 22 which are circumferentially spaced from each other by one tooth pitch of the internal teeth of ring one, are displaced from the internal teeth on either side by one-fourth of the tooth pitch of the internally toothed ring 1 shown in the drawings.
  • the control openings 21 are connected with an annular channel 23 disposed in the housing 3 and the control openings 22 with a corresponding annular channel 24.
  • the annular channel 23 is connected by an axial passage to the port 19 while the annular channel 24 is connected by passage 26 to the port 20.
  • the longitudinal grooves 17 in the rotary slide 13 act, together with the control openings 21 and 22 in the housing 3, in such a way, that the operating chambers 6 lying on one side of a line passing through the centers of the gear 5 and toothed ring 1 as viewed in FIG. 2, are connected by the control openings 21 with one port 19 while the operating chambers 6 lying on the other side of the separating line are connected to the other port 20 by the other control openings 22.
  • control openings 21 as viewed in FIG. 4 are circumferentially spaced from the control openings 22 by one half of the tooth pitch of the teeth of the toothed ring 1.
  • control openings 21 and 22 are developed as longitudinal slits running axially in the housing 3.
  • One of the ports 20 is effectively connected with an annular channel 27 disposed in the housing 3 as seen in FIG. 6, in order that all spaces in the bores formed in the gear 5, the rotary slide 13, the driving shaft 8 as well as the housing 3, can be vented through one of the pressure fluid lines and filled with a fluid pressure medium.
  • a fluid displacing device a housing (3) having separate ports (24 and 25) and to which an internal gear (1) is fixed, an external gear (5) in mesh with the internal gear to form pressure chambers (6) within the internal gear, a power shaft (8) and articulated means (7) coupling the shaft to the external gear for imparting planetary movement thereto causing expansion and contraction of said pressure chambers, a fluid distributing system including a flow controlling member (13) mounted on the coupling means having a radially outer valve surface and an axial end surface in sliding contact with the external gear, means directly connecting the flow controlling member to the power shaft for rotation thereof at the same speed as the external gear to control flow of fluid at said valve surface to and from the ports and conduit means (17-18) mounted in the flow controlling member to form passages in continuous fluid communication with the pressure chambers and said valve surface of the flow controlling member for conducting said flow of fluid between said ports and said pressure chambers during rotation of the power shaft.
  • said coupling means includes a coupling shaft having opposite ends, one of which is provided with a fork formation, a driver pin having and bearing portions pivotally connected to the power shaft and an intermediate portion of reduced cross-section presenting parallel flats engaged by the fork formation at said one of the ends of the coupling shaft and means pivotally connecting the other of the ends of the coupling shaft to the external gear.
  • conduit means comprises a plurality of external grooves opening radially outwardly and extending axially from one axial end of the flow controlling member, said grooves being circumferentially spaced from each other by one tooth pitch of the external gear, each of said grooves having a flow transition enlargement at said one axial end in fluid communication with the pressure chambers.
  • conduit means comprises separate, axially extending grooves (17) formed externally on said flow controlling member and opening radially outwardly, said grooves being cross-sectionally enlarged (18) adjacent one axial end of the flow controlling member and opening in an axial direction to establish said continuous fluid communication with the pressure chambers.
  • control openings are circumferentially spaced from the teeth of the internal gear by one quarter of the circular tooth pitch associated with the internal gear.
  • control openings in one of the separate passages are circumferentially spaced from the control openings in the other of the separate passages by one half the circular tooth pitch of the internal gear.
  • control openings are circumferentially spaced from the teeth of the internal gear by one-quarter of the circular tooth pitch associated with the internal gear.
  • control openings in one of the separate passages are circumferentially spaced from the control openings in the other of the separate passages by one half the circular tooth pitch of the internal gear.
  • said coupling means includes a coupling shaft having opposite ends, one of which is provided with a fork formation, a driver pin pivotally connected to the power shaft having end bearing portions and an intermediate portion of reduced cross-section presenting parallel flats engaged by the fork formation at said one of the ends of the coupling shaft and means pivotally connecting the other of the ends of the coupling shaft to the external gear.
  • fluid distributing means for conducting a pressure medium between the ports in the housing and said pressure spaces comprising an axially elongated member (13) having opposite axial ends and an external cylindrical valve surface, a plurality of Iongitudinal grooves (17) formed in said external valve surface and extending from one of said axial ends toward locations spaced from the other of the axial ends, means coupling the member at said other of the axial ends to the power shaft for rotation at the same speed as the external gear to control fluid communication between the ports and the grooves at said external valve surface of the member, said one of the axial ends of the member being in sliding contact with the external gear and provided with enlargements of the groove

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rotary Pumps (AREA)
  • Hydraulic Motors (AREA)
  • Power Steering Mechanism (AREA)
US355411A 1972-04-29 1973-04-30 Valve porting arrangement for a gerotor Expired - Lifetime US3887308A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2221183A DE2221183C2 (de) 1972-04-29 1972-04-29 Steuerdrehschiebereinrichtung in einer Rotationskolbenmaschine

Publications (1)

Publication Number Publication Date
US3887308A true US3887308A (en) 1975-06-03

Family

ID=5843675

Family Applications (1)

Application Number Title Priority Date Filing Date
US355411A Expired - Lifetime US3887308A (en) 1972-04-29 1973-04-30 Valve porting arrangement for a gerotor

Country Status (15)

Country Link
US (1) US3887308A (xx)
JP (1) JPS5754636B2 (xx)
AR (1) AR194331A1 (xx)
AU (1) AU471742B2 (xx)
BG (1) BG29725A3 (xx)
BR (1) BR7303066D0 (xx)
DD (1) DD104128A5 (xx)
DE (1) DE2221183C2 (xx)
ES (1) ES414169A1 (xx)
FR (1) FR2183460A5 (xx)
GB (1) GB1400108A (xx)
HU (1) HU165168B (xx)
PL (1) PL85459B1 (xx)
SE (1) SE381627B (xx)
YU (1) YU35660B (xx)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5928089A (ja) * 1983-06-06 1984-02-14 Mitsubishi Electric Corp スクロ−ル圧縮機
US4545748A (en) * 1984-07-23 1985-10-08 Parker-Hannifin Corporation Compact high torque hydraulic motors
US4872819A (en) * 1978-05-26 1989-10-10 White Hollis Newcomb Jun Rotary gerotor hydraulic device with fluid control passageways through the rotor
US5505597A (en) * 1993-12-06 1996-04-09 White Hydraulics, Inc. Pressure tolerant balanced motor valve
US5788471A (en) * 1996-06-11 1998-08-04 Eaton Corporation Spool valve wheel motor
US6193490B1 (en) * 1998-04-20 2001-02-27 White Hydraulics, Inc. Hydraulic motor valve with integral case drain
CN103696906A (zh) * 2013-12-17 2014-04-02 镇江大力液压马达股份有限公司 平稳轴阀配流摆线液压马达

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2907076C2 (de) * 1979-02-23 1984-07-05 Danfoss A/S, Nordborg Steuerdrehschiebereinrichtung für eine hydraulische Kreiskolbenmaschine
DE3152370C2 (de) * 1980-09-19 1986-06-19 Zaporožskij konstruktorsko-technologicheskij institut selskochozyaistvennogo mašinostroenia, Zaporož'e Hydraulischer Rotationskolbenmotor
JPS5797043A (en) * 1980-12-08 1982-06-16 Toyota Motor Corp Idling speed controller for internal combustion engine
DD247421B5 (de) * 1986-03-31 1995-09-21 Hydraulik Nord Gmbh Parchim Hydrostatische Lenkeinrichtung
ITBO20020757A1 (it) * 2002-12-03 2004-06-04 Sam Hydraulik Spa Motore idrostatico con distribuzione radiale.

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2121455A (en) * 1935-04-17 1938-06-21 Broek Alexander Petrus Ant Ten Universal coupling
US2153093A (en) * 1936-10-17 1939-04-04 American Steel & Wire Co Universal coupling
US3270683A (en) * 1965-08-04 1966-09-06 Char Lynn Co Porting arrangement for balancing valve of fluid pressure device
US3277833A (en) * 1964-03-16 1966-10-11 Trw Inc Hydraulic device
US3283723A (en) * 1965-07-09 1966-11-08 Germane Corp Rotary fluid pressure devices
US3289601A (en) * 1965-02-12 1966-12-06 Fawick Corp Fluid displacement device usable as a hydraulic motor or pump
US3289542A (en) * 1963-10-29 1966-12-06 Lawrence Machine & Mfg Company Hydraulic motor or pump
US3385057A (en) * 1964-08-25 1968-05-28 Trw Inc Hydraulic controller
US3446153A (en) * 1967-07-17 1969-05-27 Wayne B Easton Fluid pressure operated motor or pump

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE25291E (en) * 1956-06-08 1962-12-04 Fluid pressure device and valve
USRE25126E (en) * 1958-11-25 1962-02-20 Controller for fluid pressure operated devices
US3087436A (en) * 1960-12-02 1963-04-30 Ross Gear And Tool Company Inc Hydraulic pump
US3289602A (en) * 1965-09-03 1966-12-06 Trw Inc Fluid pressure device
AT279988B (de) * 1966-05-27 1970-03-25 Lamina Inc Hydraulikmotor
DE1553004C3 (de) * 1966-07-19 1974-09-12 Danfoss A/S, Nordborg (Daenemark) Steuerdrehschiebereinrichtung an einer Rotationskolbenmaschine
DE1931143A1 (de) * 1969-06-19 1971-02-04 Danfoss As Hydraulische Drehkolbenmaschine

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2121455A (en) * 1935-04-17 1938-06-21 Broek Alexander Petrus Ant Ten Universal coupling
US2153093A (en) * 1936-10-17 1939-04-04 American Steel & Wire Co Universal coupling
US3289542A (en) * 1963-10-29 1966-12-06 Lawrence Machine & Mfg Company Hydraulic motor or pump
US3277833A (en) * 1964-03-16 1966-10-11 Trw Inc Hydraulic device
US3385057A (en) * 1964-08-25 1968-05-28 Trw Inc Hydraulic controller
US3289601A (en) * 1965-02-12 1966-12-06 Fawick Corp Fluid displacement device usable as a hydraulic motor or pump
US3283723A (en) * 1965-07-09 1966-11-08 Germane Corp Rotary fluid pressure devices
US3270683A (en) * 1965-08-04 1966-09-06 Char Lynn Co Porting arrangement for balancing valve of fluid pressure device
US3446153A (en) * 1967-07-17 1969-05-27 Wayne B Easton Fluid pressure operated motor or pump

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4872819A (en) * 1978-05-26 1989-10-10 White Hollis Newcomb Jun Rotary gerotor hydraulic device with fluid control passageways through the rotor
JPS5928089A (ja) * 1983-06-06 1984-02-14 Mitsubishi Electric Corp スクロ−ル圧縮機
JPS6029837B2 (ja) * 1983-06-06 1985-07-12 三菱電機株式会社 スクロ−ル圧縮機
US4545748A (en) * 1984-07-23 1985-10-08 Parker-Hannifin Corporation Compact high torque hydraulic motors
US5505597A (en) * 1993-12-06 1996-04-09 White Hydraulics, Inc. Pressure tolerant balanced motor valve
US5788471A (en) * 1996-06-11 1998-08-04 Eaton Corporation Spool valve wheel motor
US6193490B1 (en) * 1998-04-20 2001-02-27 White Hydraulics, Inc. Hydraulic motor valve with integral case drain
CN103696906A (zh) * 2013-12-17 2014-04-02 镇江大力液压马达股份有限公司 平稳轴阀配流摆线液压马达
CN103696906B (zh) * 2013-12-17 2016-05-11 镇江大力液压马达股份有限公司 平稳轴阀配流摆线液压马达

Also Published As

Publication number Publication date
YU35660B (en) 1981-04-30
BR7303066D0 (pt) 1974-06-27
DD104128A5 (xx) 1974-02-20
DE2221183A1 (de) 1973-11-08
HU165168B (xx) 1974-06-28
AR194331A1 (es) 1973-06-29
BG29725A3 (en) 1981-01-15
JPS5754636B2 (xx) 1982-11-19
JPS4954905A (xx) 1974-05-28
GB1400108A (en) 1975-07-16
AU5502573A (en) 1974-10-31
SE381627B (sv) 1975-12-15
YU110173A (en) 1980-10-31
PL85459B1 (xx) 1976-04-30
ES414169A1 (es) 1976-02-16
DE2221183C2 (de) 1982-12-30
FR2183460A5 (xx) 1973-12-14
AU471742B2 (en) 1976-04-29

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