US3483890A - Multispool control valve with limited series operation - Google Patents

Multispool control valve with limited series operation Download PDF

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Publication number
US3483890A
US3483890A US646394A US3483890DA US3483890A US 3483890 A US3483890 A US 3483890A US 646394 A US646394 A US 646394A US 3483890D A US3483890D A US 3483890DA US 3483890 A US3483890 A US 3483890A
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US
United States
Prior art keywords
valve
lift
bucket
tilt
multispool
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
US646394A
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English (en)
Inventor
Dorrance Oldenburg
James E Scheidt
Donald L Shook
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 US3483890A publication Critical patent/US3483890A/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

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
    • E02F3/36—Component parts
    • E02F3/42—Drives for dippers, buckets, dipper-arms or bucket-arms
    • E02F3/43—Control of dipper or bucket position; Control of sequence of drive operations
    • E02F3/431—Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like
    • E02F3/432—Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like for keeping the bucket in a predetermined position or attitude
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F3/00—Dredgers; Soil-shifting machines
    • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
    • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
    • E02F3/36—Component parts
    • E02F3/42—Drives for dippers, buckets, dipper-arms or bucket-arms
    • E02F3/422—Drive systems for bucket-arms, front-end loaders, dumpers or the like
    • 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
    • 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
    • F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
    • 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
    • F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
    • F15B13/08—Assemblies of units, each for the control of a single servomotor only
    • 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
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30505—Non-return valves, i.e. check 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
    • F15B2211/30—Directional control
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3105—Neutral or centre positions
    • F15B2211/3116—Neutral or centre positions the pump port being open in the centre position, e.g. so-called open centre
    • 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
    • F15B2211/30—Directional control
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/321—Directional control characterised by the type of actuation mechanically
    • F15B2211/324—Directional control characterised by the type of actuation mechanically manually, e.g. by using a lever or pedal
    • 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
    • F15B2211/615—Filtering means
    • 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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • 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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/78—Control of multiple output members
    • F15B2211/781—Control of multiple output members one or more output members having priority
    • 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
    • Y10T137/87169—Supply and exhaust
    • Y10T137/87177—With bypass

Definitions

  • the valve of the present invention is designed for and will be described herein in association with the lift and tilt mechanism of a bucket loader. Its use for other purposes, however, is quite possible and will be understood as the description proceeds.
  • the bucket of a conventional loader is carried by lift arms pivoted to and extending forwardly or rearwardly from a loader tractor. Tilt linkage. controls the attitude of the bucket on the lift arms, tilting it forwardly to a dump position, or tilting it rearwardly to a rack back position. Both lift and tilt operations are controlled by hydraulic jacks, and pressure to the jacks is usually controlled by valve spools in a common housing. Valves in series are, generally speaking, preferred for controls of this type, but there are some instances where series operation is a disadvantage.
  • FIGURE 1 is a view in side elevation of the forward portion of a tractor, showing a loader bucket and illustrating schematically the various motions utilized in loading the bucket by the method known as fishtailing;
  • FIGURE 2 is a partially schematic section through a valve housing containing lift and tilt valve mechanisms embodying the present invention.
  • the tractor generally indicated at carries a bucket 11 on a pair of forwardly extending lift arms, one of which is shown at 12.
  • the lift arms can be raised and lowered about a pivot 13 by lift jacks, one of which is shown at 14.
  • the attitude of the bucket 11 on the lift arms is controlled by conventional tilt linkage generally indicated at 15, and including tilt jacks, one of which is shown at 16.
  • These jacks are operated to swing the bucket about its pivotal connection 17 with the lift arms through linkage, which is well-known.
  • Raising and lowering the buckets with the lift jack 14 imparts swinging ice movement to the lift arms 12 in the direction of the arrow labeled lift.
  • Actuation of the tilt linkage through the tilt jacks 16 causes forward and rearward swinging of the bucket about the pivot 17 in the direction of the arrow indicated as rack back-dump.
  • the power afforded by the tractor engine which also supplies power for compressing hydraulic fluid for actuating the jacks is, under some circumstances, inadequate to crowd the bucket forwardly into a supply of material and fully load the bucket in a single motion. Operators have taken to manipulating the bucket in such a manner as to acquire a full load rapidly and efliciently with the power at hand.
  • One of the most favored operations of this type is called fishtailing, and the sequential movements in this operation are indicated in FIGURE 1.
  • the bucket is shown in its load position wherein its bottom is approximately parallel to the ground, and the approach to the material to be loaded, generally indicated at 19, is made with the lift jacks 14 energized to raise the bucket 11.
  • Raising or lifting while loading the bucket is also preferred because it transfers weight to the tractor, increasing traction when it is most needed.
  • This crowding an liftting motion is continued through a distance represented as A-B in FIGURE 1, and terminates at about the point where it might be expected that the tractor and lift jacks would stall.
  • the operator actuates the tilt jacks toward rack back to raise the cutting edge through the distance B-C. This is preferably accomplished without continued lifting movement to maintain the cutting edge as low as possible when it attains the point C. This discontinuing of the lift motion occurs automatically, as will presently be explained.
  • One of the advantages of the loading cycle is that it relieves the operator of concern, as well as energy required for manipulating the lift valve during the entire operation. This is true because the lift valve is automatically taken out of control during rack back operation of the tilt cylinder. Consequently, from B to C, where lifting is not desired, the lift valve is disabled and again when the point E has been reached, racking the bucket back to its level position will disable the lift valve but, as soon as the bucket is level, the lift valve will take over automatically to raise the bucket to its carry position.
  • a valve housing generally indicated at 24 is illustrated as containing a reciprocable control spool 25 for controlling the tilt cylinders represented at 16 and a similar spool 26 for controlling the lift cylinders represented at 14. Both spools are provided with centering spring assemblies shown at 27 and 28, respectively, and of well-known construction for holding the spools in a neutral or hold position.
  • the tilt spool 25 is movable in opposite directions from the hold position between dump and rack back positions, as indicated at the left end of the spool where control linkage may be connected with it.
  • the lift spool 26 is movable to opposite sides of its hold position to raise and lower positions and also to a float position, which may be disregarded for the purposes of understanding the present invention.
  • Fluid under pressure to actuate the lift and tilt cylinders is supplied from a pump represented at 30, which delivers fluid from a reservoir 31 through a filter 32 to a passage 33 in the housing 24. With both valves in hold position as shown, the fluid under pressure passes through the cylinder of the spool 25 on opposite sides of a land 35, which is provided with the usual metering slots shown at 36. This fluid continues downwardly into a passage 37 and flows through the cylinder of the spool 26 on opposite sides of a land 38. It is then communicated to an outlet passage 39 from which it is returned to the reservoir.
  • the lift cylinder may be actuated with the tilt valve in its hold position; and as is apparent from FIGURE 2, with the lift valve shifted to its raise position, the land 38 thereon and a land 41 will close communication between passages 37 and discharge port 39.
  • pressure will open a check valve 42 biased toward its closed position by spring 43 and pass through a passage 44 and suitable metering slots 45 to a chamber 46.
  • This chamber communicates with the head end of the lift cylinders 14 by a line represented at 48.
  • fluid Upon actuation of the lift cylinder, fluid will discharge from its rod end through a line 49 communicating with a chamber 50 which, in the raised position of the valve, communicates through metering slots 51 with a chamber 52, thence through passage 53 to passage 39 to be discharged.
  • spool 25 is moved toward the right or dump position as indicated, blocking passage of fluid from chamber 33 through to spool 26 and causing pressure to open a second check valve 55. This admits fluid through passage 56 and slots 57 to chamber 58, from which pressure is com municated through a line 59 to the head end of the tilt cylinders.
  • Discharge from the rod end of the tilt cylinders is directed through a line 60 to a chamber 62, thence through slots 63 to a passage 64, which communicates with check valve 42 so that the raising function of the lift cylinders is not interrupted.
  • a passage 64 which communicates with check valve 42 so that the raising function of the lift cylinders is not interrupted.
  • Valve means suitable for actuating two sets of hydraulic motors as in the lift and tilt circuits of a bucket loader comprising first and second valves, said first valve being operable to control operation of a first set of motors in two directions, means operable when said first valve is positioned to operate said first set of motors in one direction and to direct fluid returned from said first set of motors to a second valve operable to control operation of a second set of motors for series operation, and means operable when said first valve is in position to operate said first set of motors in the opposite direction to bypass return fiuid around said second valve whereby the operability of said second set of motors is prevented.
  • each valve comprises a valve spool connected in open center relationship in a pressure circuit with series flow from said first valve to said second va'lve when the first valve is actuated in one direction, and with a bypass to source when the first valve is actuated in the opposite direction.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Operation Control Of Excavators (AREA)
US646394A 1967-06-15 1967-06-15 Multispool control valve with limited series operation Expired - Lifetime US3483890A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US64639467A 1967-06-15 1967-06-15

Publications (1)

Publication Number Publication Date
US3483890A true US3483890A (en) 1969-12-16

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ID=24592873

Family Applications (1)

Application Number Title Priority Date Filing Date
US646394A Expired - Lifetime US3483890A (en) 1967-06-15 1967-06-15 Multispool control valve with limited series operation

Country Status (7)

Country Link
US (1) US3483890A (da)
BE (1) BE707143A (da)
CH (1) CH466656A (da)
DE (1) DE1650339A1 (da)
ES (1) ES347052A1 (da)
GB (1) GB1177820A (da)
SE (1) SE322416B (da)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4066239A (en) * 1976-03-08 1978-01-03 Caterpillar Tractor Co. Metering slot configuration for a valve spool
US4122868A (en) * 1975-01-24 1978-10-31 International Harvester Company Hydraulic valve assembly having an axial flow force balanced spool

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3633617A (en) * 1970-01-28 1972-01-11 Parker Hannifin Corp Fluid system and valve assembly therefor
JPS5635806A (en) * 1979-09-01 1981-04-08 Sanyo Kiki Kk Compound oil pressure circuit

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2247140A (en) * 1937-08-09 1941-06-24 Vickers Inc Multiple valve unit
US3000397A (en) * 1959-08-24 1961-09-19 Parker Hannifin Corp Valve assembly
US3008488A (en) * 1959-11-16 1961-11-14 New York Air Brake Co Control valve
US3175580A (en) * 1962-02-09 1965-03-30 Cessna Aircraft Co Control valve for at least two hydraulic motors

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2247140A (en) * 1937-08-09 1941-06-24 Vickers Inc Multiple valve unit
US3000397A (en) * 1959-08-24 1961-09-19 Parker Hannifin Corp Valve assembly
US3008488A (en) * 1959-11-16 1961-11-14 New York Air Brake Co Control valve
US3175580A (en) * 1962-02-09 1965-03-30 Cessna Aircraft Co Control valve for at least two hydraulic motors

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4122868A (en) * 1975-01-24 1978-10-31 International Harvester Company Hydraulic valve assembly having an axial flow force balanced spool
US4066239A (en) * 1976-03-08 1978-01-03 Caterpillar Tractor Co. Metering slot configuration for a valve spool

Also Published As

Publication number Publication date
GB1177820A (en) 1970-01-14
BE707143A (da) 1968-05-27
SE322416B (da) 1970-04-06
ES347052A1 (es) 1969-03-16
CH466656A (de) 1968-12-15
DE1650339A1 (de) 1971-03-11

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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