US3779133A - Make-up valve for hydraulic control circuit - Google Patents

Make-up valve for hydraulic control circuit Download PDF

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Publication number
US3779133A
US3779133A US00264961A US3779133DA US3779133A US 3779133 A US3779133 A US 3779133A US 00264961 A US00264961 A US 00264961A US 3779133D A US3779133D A US 3779133DA US 3779133 A US3779133 A US 3779133A
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US
United States
Prior art keywords
valve means
check valve
reservoir
hydraulic fluid
passage
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
US00264961A
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English (en)
Inventor
J Dezelan
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.)
Caterpillar Inc
Original Assignee
Caterpillar Tractor Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Caterpillar Tractor Co filed Critical Caterpillar Tractor Co
Application granted granted Critical
Publication of US3779133A publication Critical patent/US3779133A/en
Assigned to CATERPILLAR INC., A CORP. OF DE. reassignment CATERPILLAR INC., A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: CATERPILLAR TRACTOR CO., A CORP. OF CALIF.
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
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors

Definitions

  • a closed reservoir is connected to a pump for delivering pressurized hydraulic fluid to a directional control selector valve operatively connected to the ends of a double-acting hydraulic cylinder.
  • a first check valve is positioned between the pump and the selector valve to pass pressurized hydraulic fluid thereby whereas a second check or make-up valve is telescopically mounted within the first check valve in exposed relationship to the hydraulic fluid contained in the reservoir.
  • the make-up valve opens when the fluid pressure in the reservoir exceeds a predetermined level whereby such fluid is communicated therethrough and to the selector valve.
  • Hydraulic control circuits for earthworking vehicles such as tractors having hydraulically actuated work implements mounted thereon, oftentimes comprise a closed reservoir which may become ruptured when the fluid pressure therein exceeds a predetermined safe level. For example, such adverse condition may arise when a work implement is lowered by a hydraulic cylinder with the engine stopped. Hydraulic fluid exhausted.
  • Applicants assignee has substantially overcome such problem by mounting a directional control selector valve within the reservoir along with a check valve positioned between the pump and selector valve and a separate, make-up valve, exposed interiorly of the tank, to relieve such unduly high fluid pressures.
  • FIG. 1 schematically illustrates an improved hydraulic control circuit having selector, check and make-up valves of this invention suitably integrated therein;
  • FIG. 2 is an end view of the valves, taken inthe direction of arrows lI-ll in FIG. 1.
  • FIG. 1 illustrates a hydraulic control circuit comprising a closed reservoir 10, shown in broken lines, adapted to be mounted on an earthworking vehicle such as a tractor.
  • a hydraulic actuator 11 preferably comprising a double-acting hydraulic cylinder, is mounted on the tractor to perform a work function such as the selective raising or lowering of a ground engaging ripper (not shown).
  • An engine driven pump means 12 communicates with the reservoir via a conduit 13 and with a directional control selector valve means via a conduit 14.
  • the selector valve means is mounted in the reservoir and is operatively connected to conduit 14 by first passage means 15, formed in a housing 16'thereof. Second passage means 17 and 18 are also formed in the housing to communicate the selector valve means with the head and rod ends of cylinder 11, respectively.
  • the selector valve means further comprises a three-position valve spool 19 adapted to be manually positioned to eit-her the lower L, hold H or raise R position of cylinder operation.
  • the valve spool is normally and automatically maintained in its illustrated H position of operation by a conventional spring assembly 20, operatively associated with the right end thereof.
  • a conventional spring assembly 20 operatively associated with the right end thereof.
  • pressurized fluid from first passage means 15 will flow past a first check valve means 21, through a slot 22 and into a passage means 17 communicating with the head end of cylinder 11 to extend same.
  • the rod end of the cylinder is exhausted via a passage means 18, a second slot 23 and an exhaust passage 24 communicating with the reservoir.
  • First check valve means 21 comprises a cup-shaped cylindrical member 27 normally urged rightwardly by a coil spring means 28 to have its closed end engage an annular seat 29 formed on the housing.
  • a second check or make-up valve means 30 comprises a similar cupshaped cylindrical member 31 telescopically mounted within member, 27. Common spring means 28 also abuts member 31 to urge its closed end leftwardly against an annular seat 32 which is axially spaced from seat 29.
  • Third passage means preferably formed through the two back-to-back check valve means, comprises a plurality of apertures 33 formed at the reduced end of member 31, the cylindrical chambers formed within members 27 and 31 and apertures 34 formed at the reduced end of member 27.
  • An end cover plate 35 of the housing preferably having seat 32 formed thereon, is secured in place by cap screws 36 (FIG. 2).
  • centrally disposed opening 37 is formed through the plate to expose the closed end of member 31 to the fluid pressure level prevalent in the reservoir. When such level exceeds a predetermined amount, valve member 31 will move rightwardly to communicate fluid from the reservoir to the third passage means, formed through the two check valve means, and to the selector control valve means.
  • a hydraulic control circuit comprising a closed reservoir for retaining hydraulic fluid therein, a hydraulic actuator, pump means communicating with said reservoir for pressurizing hydraulic fluid received therefrom, selector valve means mounted in said reservoir and operatively connected to said pump by first passage means and to said actuator by second passage means for selectively communicating said pressurized hydraulic fluid to said actuator, first check valve means in said first passage means for opening when said pressurized hydraulic fluid exceeds a first predetermined level to communicate said hydraulic fluid to said selector valve means, second check valve means exposed to said hydraulic fluid in said reservoir for opening when such hydraulic fluid exceeds a second predetermined level, and third passage means at least substantially defined by each of said first and second check valve means for communicating hydraulic fluid from said reservoir to said selector valve means upon opening of said second check valve means.
  • said hydraulic actuator comprises a double-acting hydraulic cylinder.
  • said selector valve means has three operating positions, namely (a) a first position for communicating said first passage means with a head end of said cylinder and for simultaneously exhausting a rod end of said cylinder; (b) a second position for communicating said first passage means with a rod end of said cylinder and for simultaneously exhausting the head end of said cylinder; and (c) a third position for blocking communication of said first passage means with said second passage means.
  • first and second check valve means are mounted in back-to-back relationship with respect to each other in a housing, spring means for urging said first and second check valve means away from each other and means defining axially spaced annular seats therein, each of said first and second check valve means engaging a respective one of said seats to normally close said first and third passage means, respectively.
  • each of said first and second check valve means comprises a cylindrical cup-shaped member, said cup-shaped members telescopically mounted together.
  • said third passage means comprises at least one port and an internal chamber formed within each of said cup shaped members.
  • an integrated control circuit comprising a closed reservoir, an actuator, a pump, a directional control selector valve mounted in said reservoir, check valve means for opening to communicate pressurized fluid from said pump to said selector valve and make-up valve means for opening to communicate fluid from said tank to said selector valve, the invention wherein said first and second check valve means are mounted in back-to-back relationship with respect to each other and define a continuous passage for communicating fluid from said reservoir to said selector valve upon opening of said second check valve means.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Lifting Devices For Agricultural Implements (AREA)
  • Check Valves (AREA)
US00264961A 1972-06-21 1972-06-21 Make-up valve for hydraulic control circuit Expired - Lifetime US3779133A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US26496172A 1972-06-21 1972-06-21

Publications (1)

Publication Number Publication Date
US3779133A true US3779133A (en) 1973-12-18

Family

ID=23008381

Family Applications (1)

Application Number Title Priority Date Filing Date
US00264961A Expired - Lifetime US3779133A (en) 1972-06-21 1972-06-21 Make-up valve for hydraulic control circuit

Country Status (4)

Country Link
US (1) US3779133A (enrdf_load_stackoverflow)
JP (1) JPS5616282B2 (enrdf_load_stackoverflow)
CA (1) CA971079A (enrdf_load_stackoverflow)
GB (2) GB1437199A (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3978879A (en) * 1972-08-14 1976-09-07 Danfoss A/S Control means for hydrostatic steering systems and the like
EP0396760A4 (en) * 1988-08-16 1991-01-23 Kabushiki Kaisha Komatsu Seisakusho Operation valve device
US20100059130A1 (en) * 2007-02-21 2010-03-11 Mitsuhisa Tougasaki Directional Control Valve Device and Directional Control Valve Device Block Having Directional Control Valve Devices

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61262891A (ja) * 1985-05-15 1986-11-20 オムロン株式会社 ト−クン

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3213762A (en) * 1962-09-29 1965-10-26 Sigma Hydraulic devices for reciprocating elements having high inertia
US3415160A (en) * 1966-12-08 1968-12-10 Applied Power Ind Inc Multi-speed fluid translator
US3470792A (en) * 1967-08-02 1969-10-07 Cessna Aircraft Co Maximum pressure control apparatus for hydraulic actuators

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3345998A (en) * 1965-02-19 1967-10-10 Gianni A Dotto Safety check valve

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3213762A (en) * 1962-09-29 1965-10-26 Sigma Hydraulic devices for reciprocating elements having high inertia
US3415160A (en) * 1966-12-08 1968-12-10 Applied Power Ind Inc Multi-speed fluid translator
US3470792A (en) * 1967-08-02 1969-10-07 Cessna Aircraft Co Maximum pressure control apparatus for hydraulic actuators

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3978879A (en) * 1972-08-14 1976-09-07 Danfoss A/S Control means for hydrostatic steering systems and the like
EP0396760A4 (en) * 1988-08-16 1991-01-23 Kabushiki Kaisha Komatsu Seisakusho Operation valve device
US20100059130A1 (en) * 2007-02-21 2010-03-11 Mitsuhisa Tougasaki Directional Control Valve Device and Directional Control Valve Device Block Having Directional Control Valve Devices
US8393348B2 (en) * 2007-02-21 2013-03-12 Hitachi Construction Machinery Co., Ltd. Directional control valve device and directional control valve device block having directional control valve devices

Also Published As

Publication number Publication date
GB1437200A (en) 1976-05-26
JPS5616282B2 (enrdf_load_stackoverflow) 1981-04-15
GB1437199A (en) 1976-05-26
JPS4956085A (enrdf_load_stackoverflow) 1974-05-30
CA971079A (en) 1975-07-15

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Legal Events

Date Code Title Description
AS Assignment

Owner name: CATERPILLAR INC., A CORP. OF DE.,ILLINOIS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CATERPILLAR TRACTOR CO., A CORP. OF CALIF.;REEL/FRAME:004669/0905

Effective date: 19860515

Owner name: CATERPILLAR INC., 100 N.E. ADAMS STREET, PEORIA, I

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CATERPILLAR TRACTOR CO., A CORP. OF CALIF.;REEL/FRAME:004669/0905

Effective date: 19860515