US3770076A - Hydraulic systems - Google Patents

Hydraulic systems Download PDF

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Publication number
US3770076A
US3770076A US00147594A US3770076DA US3770076A US 3770076 A US3770076 A US 3770076A US 00147594 A US00147594 A US 00147594A US 3770076D A US3770076D A US 3770076DA US 3770076 A US3770076 A US 3770076A
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US
United States
Prior art keywords
liquid
tank
main pump
temperature
vehicle
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
US00147594A
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English (en)
Inventor
P Ward
R Smith
D Siverns
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Ferranti Engineering Ltd
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Rubery Owen and Co Ltd
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Publication date
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Publication of US3770076A publication Critical patent/US3770076A/en
Assigned to RUBERY OWEN KARRITAINERS LTD.; VICTORIA ROAD GREAT SANKEY WARRINGTON WA5 S2T A COMPANY OF GREAT BRITAIN reassignment RUBERY OWEN KARRITAINERS LTD.; VICTORIA ROAD GREAT SANKEY WARRINGTON WA5 S2T A COMPANY OF GREAT BRITAIN ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: RUBERY OWEN AND COMPANY LIMITED
Assigned to FERRANTI ENGINEERING LIMITED, A COMPANY OF GREAT BRITAIN reassignment FERRANTI ENGINEERING LIMITED, A COMPANY OF GREAT BRITAIN ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: KARRITAINER LIMITED
Assigned to KARRITAINERS LIMITED reassignment KARRITAINERS LIMITED CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE DATE: 10-11-78 Assignors: RUBERY OWEN KARRITAINERS LIMITED
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0423—Cooling
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/042—Controlling the temperature of the fluid
    • F15B21/0427—Heating
    • 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
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F16F9/42—Cooling arrangements
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/01—Control of temperature without auxiliary power
    • G05D23/12—Control of temperature without auxiliary power with sensing element responsive to pressure or volume changes in a confined fluid
    • G—PHYSICS
    • G05—CONTROLLING; REGULATING
    • G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00—Control of temperature
    • G05D23/185—Control of temperature with auxiliary non-electric power
    • 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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/26—Supply reservoir or sump assemblies
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
    • F15B2211/50518—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using pressure relief valves
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/51—Pressure control characterised by the positions of the valve element
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5157—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source and a return line
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/61—Secondary circuits
    • F15B2211/611—Diverting circuits, e.g. for cooling or filtering
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/62—Cooling or heating means

Definitions

  • ABSTRACT In an hydraulic system a pump draws liquid from a header tank by way of an auxiliary tank which is connected to the header tank, and the discharge from the pump is fed to either tank or partly to each tank under the control of a diverter valve in order to maintain the temperature of the working liquid within desired limits.
  • One object of our invention is to provide means whereby the temperature of the working liquid in an hydraulic system is maintained substantially constant independently of climatic conditions.
  • a pump draws liquid from a header tank by way of an auxiliary tank which is connected to the header tank, and the discharge from the pump is fed to either tank or partly to each tank under the control of a diverter valve in order to maintain the temperatue of the working liquid within desired limits.
  • the header tank may comprise a radiator located in a relatively exposed position on the vehicle or machine incorporating the hydraulic system.
  • the auxiliary tank is preferably located in a part of the vehicle or machine which is normally warm, as for example an engine bay, and is provided with means such as an electric immersion heater for heating the liquid. This tank may be thermally insulated.
  • FIG. 1 is a circuit diagram for an hydraulic transmission system
  • FIG. 2 is a diagrammatic representation of the temperature sensitive diverter valve included in the system of FIG. 1, and
  • FIG. 3 is a sketch of a vehicle incorporating the system of FIG. 1.
  • FIG. 3 One application of the hydraulic system shown is in the transmission system of a vehicle for handling freight containers, known as a straddle carrier and illustrated in FIG. 3.
  • the vehicle has an arched .frame 25 supported at each side by a set of hydraulically driven wheels 26 and can straddle a stack of two or, in one version, three freight containers.
  • An internal combustion engine 1 on each side of the frame 25 drives hydrostatic pumps 2 and 3 which provide hydraulic fluid for a motor27 drawing each wheel 26, the pumps and motors being connected in the closed loop hydraulic circuit of FIG. 1.
  • the engine 1 drives variable delivery main pump 2 and a booster pump 3 which keeps the main pump primed and makes good the losses in the system.
  • the booster pump 3 draws hydraulic liquid from a header tank 4 located high up on the vehicle via an auxiliary tank 5 located in the engine bay.
  • This auxiliary tank 5 is a section of pipe which serves as a junction for a number of hydraulic pipes leading drainage liquid from motors and components back into the system and conveniently provides a reservoir of liquid.
  • An electric immersion heater 6 is provided in this tank for a purpose to be described.
  • the booster pump 3 discharges through a filter 7 having a by-pass 8 to the suction side of the main pump 2.
  • the main pump 2 delivers pressure liquid for the wheel motors and lifting and other hydraulic services on the vehicle via a main hydraulic control valve 9.
  • the diverter valve 11 Surplus liquid from the booster pump 3 is discharged through a relief valve 10 to the inlet of a thermostatically controlled diverter valve 11.
  • the diverter valve 11 has two outlets 12, l3,one 12 connected to the auxiliary tank 5, and the other 13 to the header tank 4.
  • the main pump 2 also discharges via the main control valve 9 and relief valve 10 to the diverter valve 1 1 when none of the services supplied by it are being operated.
  • FIG. 2 One type of diverter valve that can be used is shown in FIG. 2. It comprises a body 14 having an inlet port 15 at one end the and outlet ports 12, 13 at the side one above the other. A hollow piston valve 16 is slidable in a bore 17 in the body 14 between extreme positions in which one or the other of the outlet ports 12, 13 is sealed. Between these extreme positions both ports may be open, the extent of their opening being determined by the position of the piston valve 16 in relation to these ports.
  • the piston 16 is connected to one part of a wax-filled thermostatic element 18 and is biassed by a spring 19 to a position in which it seals the outlet port 13 to the header tank 4.
  • the element 18 is also engaged by a separate piston 20 slidable in a bore 21 in an end cap 22 of the valve.
  • the position of the piston 20 is regulated by a screwed adjuster 23 so that the temperature set-' ting of the element 18 is adjustable. In this position liquid discharged by the booster pump 3 is returned to the auxiliary tank 5. As the liquid warms up it acts on the thermostatic element which commences to expand-and moves the piston 16 so as to open the outlet port 13 to the header tank 4.
  • the piston 16 moves to seal the outlet port 12 to the auxiliary tank 5 so that all the fluid is passed to the header tank 4 for cooling before returning to the auxiliary tank 5
  • the liquid in the auxiliary tank 5 can be kept at a desired working temperature by the electric immersion heater 6. This insures an adequate supply of warm liquid to keep the main pump system primed, and liquid circulated by the main pump 2 is returned mainly to the auxiliary tank 5 until the liquid in the whole system attains the required working temperature, as determined by the setting of the ther- It will be appreciated that the diverter valve 11 may be located elsewhere in the system.
  • the diverter valve 11 may conveniently be located in a part of the system which is subjected to pressure.
  • the hydraulic systems on each side of the straddle carrier may be interconnected and, in particular, the two header tanks may be connected.
  • the header tank may comprise a radiator with natural or forced cooling.
  • the system described above can be incorporated in travelling hoists for freight containers or in any other type of hydraulically powered machine or vehicle for which it is desirable to maintain the temperature and thus the viscosity of the hydraulic fluid substantially constant.
  • a vehicle for handling freight containers comprising an arched frame, a set of wheels supporting each side of the frame, and engine on each side of the frame, a main pump and a booster pump driven by each engine, the wheels of each set being driven by pressure liquid from the main pump, an auxiliary tank 7 from which the booster pump draws liquid for supplying the suction side of the main pump, a header tank connected to the auxiliary tank means for maintaining a difference in temperature between the liquids in each tank, a diverter valve having an inlet port connected to the discharge side of the main pump, an outlet port connected to the auxiliary tank and a second outlet port connected to the header tank, and a temperature sensitive element arranged in the liquid discharged from the main pump to control the operation of the diverter valve whereby the liquid from the main pump is directed between the auxiliary and header tanks in accordance with the temperature of the liquid to maintain the temperature of the working liquid within desired limits.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Power Engineering (AREA)
  • Auxiliary Drives, Propulsion Controls, And Safety Devices (AREA)
  • Reciprocating Pumps (AREA)
US00147594A 1970-05-28 1971-05-27 Hydraulic systems Expired - Lifetime US3770076A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2565770 1970-05-28

Publications (1)

Publication Number Publication Date
US3770076A true US3770076A (en) 1973-11-06

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ID=10231224

Family Applications (1)

Application Number Title Priority Date Filing Date
US00147594A Expired - Lifetime US3770076A (en) 1970-05-28 1971-05-27 Hydraulic systems

Country Status (8)

Country Link
US (1) US3770076A (xx)
JP (1) JPS5529287B1 (xx)
AU (1) AU2933871A (xx)
BE (1) BE767588A (xx)
CA (1) CA929072A (xx)
DE (1) DE2126485A1 (xx)
GB (1) GB1337112A (xx)
SE (1) SE370997B (xx)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3878911A (en) * 1974-03-08 1975-04-22 William J Nichols Hydraulically propelled high clearance agricultural vehicle
US5335739A (en) * 1992-12-30 1994-08-09 Ian Pieterse Agricultural vehicle
US20110308274A1 (en) * 2008-11-20 2011-12-22 Danfoss A/S An expansion valve comprising a diaphragm and at least two outlet openings
US20150354697A1 (en) * 2014-06-10 2015-12-10 Ford Global Technologies, Llc Dual sump transmission hydraulic control system
CN107842537A (zh) * 2017-12-11 2018-03-27 徐工集团工程机械有限公司 端盖总成、液压设备及工程机械

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3716289A1 (de) * 1987-05-15 1988-11-24 Leybold Ag Einrichtung fuer die herstellung bestimmter konzentrationen gasfoermiger stoffe sowie zum mischen verschiedener gasfoermiger stoffe in einem vorgegebenen verhaeltnis
DE4431951A1 (de) * 1994-09-08 1996-03-14 Same Spa Hydraulikanlage
SE526236C2 (sv) * 2003-12-23 2005-08-02 Oehlins Racing Ab Anordning vid fordon
CN105822610A (zh) * 2016-04-27 2016-08-03 安徽合力股份有限公司 一种液压油箱的油温控制系统
CN111536100B (zh) * 2020-04-30 2022-09-06 肇庆学院 一种液压元件高加速试验台温控系统及温控方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1637596A (en) * 1916-12-30 1927-08-02 Turner Edgar Ames Heater for automobile water-cooling systems
US2435041A (en) * 1945-02-10 1948-01-27 Frederic W Hild Regulating device for cooling systems
US2457618A (en) * 1944-02-08 1948-12-28 Sulzer Ag Temperature regulated cooling circuit
US3160223A (en) * 1961-09-08 1964-12-08 Renner Mfg Company Vehicular steering

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1637596A (en) * 1916-12-30 1927-08-02 Turner Edgar Ames Heater for automobile water-cooling systems
US2457618A (en) * 1944-02-08 1948-12-28 Sulzer Ag Temperature regulated cooling circuit
US2435041A (en) * 1945-02-10 1948-01-27 Frederic W Hild Regulating device for cooling systems
US3160223A (en) * 1961-09-08 1964-12-08 Renner Mfg Company Vehicular steering

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3878911A (en) * 1974-03-08 1975-04-22 William J Nichols Hydraulically propelled high clearance agricultural vehicle
US5335739A (en) * 1992-12-30 1994-08-09 Ian Pieterse Agricultural vehicle
US20110308274A1 (en) * 2008-11-20 2011-12-22 Danfoss A/S An expansion valve comprising a diaphragm and at least two outlet openings
JP2012509455A (ja) * 2008-11-20 2012-04-19 ダンフォス アクチ−セルスカブ ダイヤフラムおよび少なくとも２の出口開口を備える膨張弁
US20150354697A1 (en) * 2014-06-10 2015-12-10 Ford Global Technologies, Llc Dual sump transmission hydraulic control system
CN105276172A (zh) * 2014-06-10 2016-01-27 福特全球技术公司 双油底壳变速器液压控制系统
CN105276172B (zh) * 2014-06-10 2019-11-01 福特全球技术公司 双油底壳变速器液压控制系统
US10941856B2 (en) * 2014-06-10 2021-03-09 Ford Global Technologies, Llc Dual sump transmission hydraulic control system
CN107842537A (zh) * 2017-12-11 2018-03-27 徐工集团工程机械有限公司 端盖总成、液压设备及工程机械
CN107842537B (zh) * 2017-12-11 2024-04-30 江苏徐工工程机械研究院有限公司 端盖总成、液压设备及工程机械

Also Published As

Publication number Publication date
CA929072A (en) 1973-06-26
JPS5529287B1 (xx) 1980-08-02
DE2126485A1 (de) 1972-01-13
BE767588A (fr) 1971-10-18
GB1337112A (en) 1973-11-14
SE370997B (xx) 1974-11-04
AU2933871A (en) 1972-11-30

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AS Assignment

Owner name: KARRITAINERS LIMITED

Free format text: CHANGE OF NAME;ASSIGNOR:RUBERY OWEN KARRITAINERS LIMITED;REEL/FRAME:003934/0729

Effective date: 19781011

Owner name: RUBERY OWEN KARRITAINERS LTD.; VICTORIA ROAD GREAT

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:RUBERY OWEN AND COMPANY LIMITED;REEL/FRAME:003934/0723

Effective date: 19780119

Owner name: FERRANTI ENGINEERING LIMITED; HOLLINWOOD AVE., CHA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:KARRITAINER LIMITED;REEL/FRAME:003934/0730

Effective date: 19810901