US3882678A - Automatic connecting valves for reserve pumps - Google Patents

Automatic connecting valves for reserve pumps Download PDF

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Publication number
US3882678A
US3882678A US476432A US47643274A US3882678A US 3882678 A US3882678 A US 3882678A US 476432 A US476432 A US 476432A US 47643274 A US47643274 A US 47643274A US 3882678 A US3882678 A US 3882678A
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US
United States
Prior art keywords
flow
valve
reserve
main
pump
Prior art date
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
US476432A
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English (en)
Inventor
Rolf Fassbender
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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Filing date
Publication date
Application filed by ZF Friedrichshafen AG filed Critical ZF Friedrichshafen AG
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Publication of US3882678A publication Critical patent/US3882678A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/30—Safety devices, e.g. alternate emergency power supply or transmission means to ensure steering upon failure of the primary steering means
    • B62D5/32—Safety devices, e.g. alternate emergency power supply or transmission means to ensure steering upon failure of the primary steering means for telemotor systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
    • F16K11/02—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit
    • F16K11/06—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements
    • F16K11/065—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members
    • F16K11/07—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides
    • F16K11/0716—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides with fluid passages through the valve member
    • 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
    • Y10T137/2496—Self-proportioning or correlating systems
    • Y10T137/2559—Self-controlled branched flow systems
    • Y10T137/2564—Plural inflows
    • Y10T137/2572—One inflow supplements another
    • 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
    • Y10T137/2496—Self-proportioning or correlating systems
    • Y10T137/2559—Self-controlled branched flow systems
    • Y10T137/2574—Bypass or relief controlled by main line fluid condition
    • Y10T137/2579—Flow rate responsive
    • Y10T137/2587—Bypass or relief valve biased open

Definitions

  • the effect is achieved in two embodiments of the invention by means of a valve which is spring biased to a closed flow condition of the main stream from a main pump, but opening the main flow responsive to consumer unit demand, while, however, permitting continuous reserve pump flow to reach the consumer unit prior to such opening.
  • a pilot stream from the main pump establishes a pressure differential on the valve to control response to main pump failure for cutting in the reserve .pump.
  • the pilot flow is through a pressure chamber means in which a drop in pressure due either to unit demand or main pump failure is effective to cause valve actuation for main flow opening, or valve opening for reserve pump flow.
  • An important feature of the invention resides in the fact that the pressure drop is achieved either by loss of main pump pressure or reduction in discharge rate, e.g., due to a slipping drive belt of the main pump.
  • the invention comprises a valve construction, which, for simplicity, is of the slidable piston valve type having annular grooves which coact for flow control of main and reserve pumps with annular grooves in a valve housing and connecting with inlet means from the pump and outlet means for exhaust of the reserve pump and connection to a consumer unit.
  • Each end of the piston valve is exposed to a pressure chamber across which is a pressure differential when the main pump is operative. Such pressure differential is effected by main pump pressure causing a pilot flow between the chambers through a choke passage.
  • a spring normally biases the piston valve to main flow shut-off except for the pilot flow in one embodiment, although in a second embodiment the pilot flow is likewise shut-off until there is a drop in pressure of one of the pressure chambers increasing the pressure differential sufficiently to overcome the spring bias for opening main flow to a consumer unit.
  • the upstream pressure chamber is always connected to the main pump while the downstream pressure chamber is always connected to the consumer unit. Accordingly, when pressure is dropped in the downstream chamber upon demand of the consumer unit by virtue of the valving therein being opened, the differential pressure increase effects the actuation of the piston valve essentially due to output pressure of an operative main pump.
  • main flow is connected and reserve flow shut-off.
  • the invention has an advantage over previous known arrangements for the reason that the valving is responsive not only to pressure drop but also to some malfunction effecting flow rate reduction through the choke passage which translates flow rate into pressure differential. This causes the piston valve to be responsive to flow rate whereby a reduction causes a decrease in differential pressure and permits the spring to shift the piston valve to the initial position in order to make certain of connection to the reserve pump.
  • Prior art devices are responsive only to pressure drop and it would be possible for a main pump to maintain a sufficient pressure to keep the reserve pump shut off through the valve and yet not provide a sufficient discharge rate for the consumer device. This, of course, makes it virtually impossible, for example, to steer a vehicle. In other words, the diminishing of main pump discharge rate provides insufficient pilot stream to maintain proper pressure differential for holding the piston valve in main flow open condition.
  • FIG. 1 is a longitudinal cross section of the valve construction showing connections to pumps, a tank, and a consumer unit, wherein there is continuous pilot flow from the main pump through the valve feeding to the consumer unit at all times that the main pump is operative.
  • FIG. 2 is a longitudinal cross section of an embodiment wherein pilot flow is normally cut off until differential pressure on the piston valve effects movement for establishment of the pilot flow and wherein grooves of the valve construction supplant one of the check valves of the previous embodiment for preventing flow short circuit.
  • the invention comprises a construction having a housing 1 with a throughbore 2 in which is slidably disposed a spool or sleeve-like piston valve 3. Suitable conduit connection fittings, e.g. 20, close bore 2, as shown, at one end. At each end of the housing is a pressure chamber such as the pressure chamber 4 at the upstream end of bore 2 and the pressure chamber 5 at the downstream end. Pressure chamber 4 connects via conduit or line 6 to the main pump 7 for ultimate feed to a pressureoperated unit 8, such as a booster steering device, via line 9 connecting to pressure chamber 5. Flow takes place at a relatively small rate from chamber 5 and is continuous while pump 7 is operative.
  • Housing 1 has a port 11 for intake from a reserve pump 12, further on the housing has a port 13 connecting to unit 8, and the housing also has an outlet port 14 connecting to the oil reservoir or tank 15. Port 13 communicates with a housing groove 16 and port 14 connects with a housing groove 17.
  • Piston valve 3 is provided with radial bore 18 and axial throughbore 19 for communication to annular groove 20 which is thus connected with pressure in chamber 4.
  • the piston valve also has an annular groove 21 which in all positions of the piston valve communicates with port 11 for inflow of pressure feed from reserve pump 12 either to feed unit 8 or exhaust to tank 15.
  • Bore l9 terminates in a choke passage 22 leading to pressure chamber 5 and pressure chamber 5 communicates with a check valve 23 in fitting 2a closing in the direction of the pressure chamber 5 by spring bias as shown. Accordingly, it will be understood that fluid flow from main pump 7 can effect passageway by virtue of pressure opening check valve 23 to reach unit 8 via line 9. However, such flow consists of a relatively small control or pilot stream causing a differential pressure in chambers 4 and 5 due to the choke passage 22 to effect automatic shifting of piston valve 3. Thus, the upstream chamber 4 would have a greater pressure to cause shifting of the piston valve to the left to send flow from pump 7 to unit 8 via passages 19, 18, 20, l6, l3, 9 and a check valve 24.
  • FIG. 2 differs essentiallyifrom that shown in FIG. 1 in that there is no check valve of a gap D2 is relied on to block a short-circuiting of the reserve pump 1 12 in the event of failure of the main' pump 107 should piston valve 103 be in open position I at the time of such failure.
  • the components of FIG. 2 comprise the housi f ing 101 having the piston valve 103 slidable therein, with an upstream pressure chamber 104 fedvia line a 106 from main pump 107.
  • Differential pressure can w occur between upstream chamber 104 and downstream? chamber 105 only after leftward shift of the piston.”
  • valve acting against spring 110 which in neutral position maintains the piston valve 103 in its limiting position toward the right.
  • Flow from reserve pump 112] passes through open gap B2 and then to the line than feeds unit 108, all as hereinabove described.
  • the choke passage 122 is a radial bore in the pis-f 1 ton valve, which will be seen to connect to the axial I chamber 105 upon shift.
  • Feed to line 109 is viaa radial bore 103a in the end skirt formation of the piston valve.
  • the gap C1 has neither too much overlap, nor too little, so that upon actuation of the piston valve there willbe a quick change for full flow from the reserve pump.
  • the rapidity of valve actuation may be provided for a'relatively large choke passage 22 in the case of FIG. 1 or 122 in the case of HO. 2.
  • the invention provides pressure feed to a consumer unit at all times with a minimum of leakage.
  • valve means comprising a housing having a main pump inlet and a reserve pump inlet; said valve having passage means for a pilot stream and main flow from said main pump; outlet means for main flow from said main pump and reserve flow'from said reserve pump to a consumer unit; actuable valve means in said housing; said valve means and'said housing having coacting elements relatively positionable to open main flow to said outlet means and close reserve flow or to close main flowand open reserve flow to said outlet means;
  • bias means normally biasing said valve means to close main flow and open reserve flow to said outlet means
  • pressure differential means comprising upstream and downstream pressurechambermeans operative to actuate said valve means to overcome said bias means to open main'flow and close reserve flow upon'increase ofpressure differential; further comprising choke passage means operable to pass said pilot' stream from said upstream to said downstream pressure chambenmeans; and a connection from said downstream pressure chamber means to said outlet'means whereby a reduction in pressure differential to a predetermined value permits said bias means to actuate said valve means to effect reserve flow to said consumer unit.
  • a valve for controlling main flow from a main 2.
  • a housing having a main pump inlet and a reserve pump inlet
  • main flow outlet means for main flow from said main pump and for reserve flow from said reserve pump. to a consumer unit;
  • valve means and said housing having coacting elements relatively positionable to open main flow to said outlet means and close reserve flow, or, to close main flow and open reserve flow to said outlet means;
  • hias means normally biasing said valve means to close main flow and open reserve flow to said outlet means;
  • pressure differential means comprising communicable upstream and downstream pressure chamber means effecting pressures operative on said valve means to actuate said valve means against said bias means to open main flow and close reserve flow upon relative increase of pressure in said upstream chamber means; said pressure differential means comprising pilot stream means providing pilot flow from said main pump to said upstream pressure chamber means to effect a normally higher pressure therein for maintaining said valve means in an actuated position;
  • a valve for controlling main flow from a main pump and reserve flow from a reserve pump, to a consumer unit comprising a housing having a main pump a reserve pu'mp inlet; main flow outlet means for main flow from said main pump and for reserve flow from said reserve pump, to a consumer unit; l actuable valve means in said housing; said valve means and said housing having coacting elements relatively positionable to open main flow to said outlet means and close reserve flow, or, to close main flow and open reserve flow to said outlet means; bias means normally biasing said valve means to close inlet and main flow and open reserve flow to said outlet means;
  • differential pressure differential means comprising upstream and downstream pressure chamber means having pressures acting on said valve means operative to overcome said bias means andactuate said valve means to open-main flow and close reserve flow; said differential pressure means comprising pilot stream means providing a pilot stream flowing from said upstream to said downstream pressure chamber-means in an actuated position of said valve means when said main pump is operative to effect a relative reduction of pressure in said downstream pressure chamber means whereby a predetermined differential pressure maintains main flow to said outlet means;
  • a housing having a main pump inlet and a reserve pump inlet
  • valve having passage means for a pilot stream and main flow from said main pump; outlet means for main flow from said main pump and reserve flow from said reserve pump to a consumer unit;
  • valve means and said housing having coacting elements relatively positionable to open main flow to said outlet means and close reserve flow, or, to close main flow and open reserve flow to said outlet means;
  • v bias means normally'biasing said valve means to close main flow and openreserve flow to said outlet means- .1
  • pressuredifferential means comprising upstream and downstream pressure chamber meansoperative to actuate said valve means to overcome said .bias meansto open main flow and close reserve flow upon increase of pressure differential;
  • said pressure differential means being operable to permit flow ofsaid pilot stream from said upstream to said downstream pressureehamber means and effecting a pressure drop in the course of said flow;
  • valve means co'm'prising'a slidablejpiston valve having a throughbore connecting with said upstream pressure chamber means;
  • said housing having a bore; said piston valve being slidable in said bores said pressure chamber means being portions'of said bore at opposite respective ends of saidp'isto'n,
  • piston valve and housing have'respec tive coacting grooves for control of flow from said pumps to said consumer unit;
  • a valve as set forth in claim 5 said housing hav- 12.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid Mechanics (AREA)
  • Transportation (AREA)
  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Multiple-Way Valves (AREA)
  • Power Steering Mechanism (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Safety Valves (AREA)
  • Servomotors (AREA)
US476432A 1973-06-08 1974-06-05 Automatic connecting valves for reserve pumps Expired - Lifetime US3882678A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2329328A DE2329328C2 (de) 1973-06-08 1973-06-08 Automatisches Zuschaltventil

Publications (1)

Publication Number Publication Date
US3882678A true US3882678A (en) 1975-05-13

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US476432A Expired - Lifetime US3882678A (en) 1973-06-08 1974-06-05 Automatic connecting valves for reserve pumps

Country Status (10)

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US (1) US3882678A (it)
JP (1) JPS5818521B2 (it)
BR (1) BR7404655D0 (it)
DE (1) DE2329328C2 (it)
ES (1) ES426731A1 (it)
FR (1) FR2232715B1 (it)
GB (1) GB1469458A (it)
IT (1) IT1013262B (it)
SE (1) SE398623B (it)
YU (1) YU39071B (it)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4068678A (en) * 1975-04-26 1978-01-17 Zahnradfabrik Friedrichshafen Ag Valve for hydraulic systems
US4073140A (en) * 1975-03-21 1978-02-14 Zahnradfabrik Friedrichshafen Ag Connecting valve for reserve pump
US4237993A (en) * 1977-07-15 1980-12-09 Zahnradfabrik Friedrichshafen Ag Auxiliary power steering for motor vehicles
US4242867A (en) * 1978-04-01 1981-01-06 Itt Industries, Inc. Standby supply system for delivering pressure fluid to a user component
US4275865A (en) * 1977-08-24 1981-06-30 Lucas Industries Limited Fluid control valves
US4306840A (en) * 1978-06-10 1981-12-22 Zahnradfabrik Friedrichshafen, Ag. Automatic connecting valve for hydraulic systems
US4357995A (en) * 1980-12-22 1982-11-09 Westinghouse Electric Corp. Hydraulic system including oil replenishment for multi-stage hydraulic jack
US6116217A (en) * 1998-09-29 2000-09-12 Stanadyne Automotive Corp. Full authority rail pressure-reduction valve
US20070039782A1 (en) * 2005-07-28 2007-02-22 J.C. Bamford Excavators Limited Providing lubricant to an engine
US20070199316A1 (en) * 2006-02-27 2007-08-30 Moorman Steven P Hybrid powertrain with valve assembly for dual pumps
US9052712B2 (en) * 2012-10-26 2015-06-09 Hamilton Sundstrand Corporation Regulator valve with axial vent
CN104742964A (zh) * 2013-12-26 2015-07-01 湖北万山宏业汽车零部件有限公司 工程机械用应急转向系统
US9108476B2 (en) 2012-07-19 2015-08-18 The Goodyear Tire & Rubber Company Bypass air maintenance tire and pump assembly
CN106286925A (zh) * 2016-08-17 2017-01-04 中国航空工业集团公司西安飞行自动控制研究所 一种新型稳压溢流阀
US9840273B2 (en) 2015-12-07 2017-12-12 Caterpillar Inc. Electrohydraulic steering system with diagnostics
JP2018162859A (ja) * 2017-03-27 2018-10-18 日本電産トーソク株式会社 スプールバルブ
US10190718B2 (en) 2016-06-08 2019-01-29 Baker Hughes, A Ge Company, Llc Accumulator assembly, pump system having accumulator assembly, and method
CN110318886A (zh) * 2019-07-16 2019-10-11 中国航发沈阳发动机研究所 一种基于双联齿轮泵的燃油计量系统及其匹配方法

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5345379U (it) * 1976-09-20 1978-04-18
JPS5464332A (en) * 1977-10-17 1979-05-24 Honda Motor Co Ltd Automotive power steering device
DE2800405C2 (de) * 1978-01-05 1986-10-02 Zahnradfabrik Friedrichshafen Ag, 7990 Friedrichshafen Hydraulische Hilfskraftlenkung für Kraftfahrzeuge mit einem Umschaltventil zum Zuschalten einer Reservepumpe
JPS55139531A (en) * 1979-04-13 1980-10-31 Akebono Brake Ind Co Ltd Method of preventing generation of noise at actuating disk brake and disk brake capable of preventing generation of noise at actuating brake
DE2924222C2 (de) * 1979-06-15 1985-09-05 Pierburg Gmbh & Co Kg, 4040 Neuss Steuerventilanordnung für eine Einrichtung zur Erzeugung von Unterdruck für unterdruckverbrauchende Systeme
DE3210759A1 (de) * 1981-09-17 1983-10-06 Walter Schopf Pumpenkombination mit mengenreguliereinrichtung
JPH0629040B2 (ja) * 1984-10-11 1994-04-20 光洋精工株式会社 動力舵取装置の油圧反力制御装置
GB2171778B (en) * 1985-03-01 1988-11-30 Coal Ind Hydraulic valve block for determining the operational condition of hydraulic circuits
NL8501474A (nl) * 1985-05-23 1986-12-16 Dow Chemical Nederland Omschakelklep.
JPS63115935U (it) * 1987-01-20 1988-07-26
JPS63146234U (it) * 1987-03-18 1988-09-27
DE102004058261A1 (de) * 2004-12-03 2006-06-08 Volkswagen Ag Pumpe mit zwei Pumpstufen und Verfahren zur Ölversorgung eines Fahrzeuggetriebes und einer dem Fahrzeuggetriebe zugehörigen Kupplungsanordnung
DE102007012716B4 (de) * 2007-03-16 2010-01-28 GM Global Technology Operations, Inc., Detroit Hybridantriebsstrang mit einer Ventilanordnung für zwei Pumpen
WO2010038622A1 (ja) * 2008-10-01 2010-04-08 株式会社 島津製作所 流量制御弁装置

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2440371A (en) * 1946-02-01 1948-04-27 George M Holley Emergency pump

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2158870C2 (de) * 1971-11-27 1973-09-27 Eaton Gmbh, 5620 Velbert Hydraulische Servoanlage mit zwei Pumpen und mehreren Hydromotoren

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2440371A (en) * 1946-02-01 1948-04-27 George M Holley Emergency pump

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4073140A (en) * 1975-03-21 1978-02-14 Zahnradfabrik Friedrichshafen Ag Connecting valve for reserve pump
US4068678A (en) * 1975-04-26 1978-01-17 Zahnradfabrik Friedrichshafen Ag Valve for hydraulic systems
US4237993A (en) * 1977-07-15 1980-12-09 Zahnradfabrik Friedrichshafen Ag Auxiliary power steering for motor vehicles
US4275865A (en) * 1977-08-24 1981-06-30 Lucas Industries Limited Fluid control valves
US4242867A (en) * 1978-04-01 1981-01-06 Itt Industries, Inc. Standby supply system for delivering pressure fluid to a user component
US4306840A (en) * 1978-06-10 1981-12-22 Zahnradfabrik Friedrichshafen, Ag. Automatic connecting valve for hydraulic systems
US4357995A (en) * 1980-12-22 1982-11-09 Westinghouse Electric Corp. Hydraulic system including oil replenishment for multi-stage hydraulic jack
US6116217A (en) * 1998-09-29 2000-09-12 Stanadyne Automotive Corp. Full authority rail pressure-reduction valve
US20070039782A1 (en) * 2005-07-28 2007-02-22 J.C. Bamford Excavators Limited Providing lubricant to an engine
US7516729B2 (en) * 2005-07-28 2009-04-14 J.C. Bamford Excavation Limited Providing lubricant to an engine
US7415820B2 (en) 2006-02-27 2008-08-26 Gm Global Technology Operations, Inc. Hybrid powertrain with valve assembly for dual pumps
US20070199316A1 (en) * 2006-02-27 2007-08-30 Moorman Steven P Hybrid powertrain with valve assembly for dual pumps
US9108476B2 (en) 2012-07-19 2015-08-18 The Goodyear Tire & Rubber Company Bypass air maintenance tire and pump assembly
US9052712B2 (en) * 2012-10-26 2015-06-09 Hamilton Sundstrand Corporation Regulator valve with axial vent
CN104742964A (zh) * 2013-12-26 2015-07-01 湖北万山宏业汽车零部件有限公司 工程机械用应急转向系统
US9840273B2 (en) 2015-12-07 2017-12-12 Caterpillar Inc. Electrohydraulic steering system with diagnostics
US10190718B2 (en) 2016-06-08 2019-01-29 Baker Hughes, A Ge Company, Llc Accumulator assembly, pump system having accumulator assembly, and method
CN106286925A (zh) * 2016-08-17 2017-01-04 中国航空工业集团公司西安飞行自动控制研究所 一种新型稳压溢流阀
CN106286925B (zh) * 2016-08-17 2018-11-16 中国航空工业集团公司西安飞行自动控制研究所 一种新型稳压溢流阀
JP2018162859A (ja) * 2017-03-27 2018-10-18 日本電産トーソク株式会社 スプールバルブ
US20190093678A1 (en) * 2017-03-27 2019-03-28 Nidec Tosok Corporation Spool valve
US10495119B2 (en) * 2017-03-27 2019-12-03 Nidec Tosok Corporation Spool valve
CN110318886A (zh) * 2019-07-16 2019-10-11 中国航发沈阳发动机研究所 一种基于双联齿轮泵的燃油计量系统及其匹配方法

Also Published As

Publication number Publication date
YU39071B (en) 1984-04-30
SE398623B (sv) 1978-01-09
ES426731A1 (es) 1976-07-01
FR2232715B1 (it) 1981-01-30
DE2329328A1 (de) 1975-01-02
GB1469458A (en) 1977-04-06
JPS5818521B2 (ja) 1983-04-13
DE2329328C2 (de) 1985-03-28
YU145874A (en) 1982-05-31
SE7407132L (it) 1974-12-09
BR7404655D0 (pt) 1974-12-03
IT1013262B (it) 1977-03-30
FR2232715A1 (it) 1975-01-03
JPS5032374A (it) 1975-03-29

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