US3592107A - Hydraulic control system - Google Patents

Hydraulic control system Download PDF

Info

Publication number
US3592107A
US3592107A US829655A US3592107DA US3592107A US 3592107 A US3592107 A US 3592107A US 829655 A US829655 A US 829655A US 3592107D A US3592107D A US 3592107DA US 3592107 A US3592107 A US 3592107A
Authority
US
United States
Prior art keywords
control
hydraulic
fluid
toolholder
arms
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
US829655A
Other languages
English (en)
Inventor
Gosta Ahlenius
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.)
BRODERNA LUNDBERGS MEKANISKA VERKSTAD AB
LUNDBERGS MEK BRDR
Original Assignee
LUNDBERGS MEK BRDR
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 LUNDBERGS MEK BRDR filed Critical LUNDBERGS MEK BRDR
Application granted granted Critical
Publication of US3592107A publication Critical patent/US3592107A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • E02F3/433—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 horizontal, e.g. self-levelling

Definitions

  • the tool of the constructional machine can be made to assume a con stant angle with the underlying surface during raising or lower ing of the booms supporting the tool in order that material car ried by the tool shall not fall out.
  • simultane ous control of the vertical positions of the booms and of the angular position of the tool in relation to the booms can be effected manually from the driver's cabin of the constructional machine.
  • the devices for parallel linkage of the toolholder must be robustly dimensioned, and must be so designed moreover that the tool can be used for dumping and bending up irrespective of the positions of the booms, it is difficult to avoid that the parallel linkage devices involve some limitation on the means for operation of the tool. This means that many operations take a longer time than if the maneuverability is unlimited. This has an unfavorable effect on the operating costs.
  • the present invention is intended to eliminate these draw backs and to provide a cheap and reliable device which by simple means solves the problem of parallel linkage of toolholders.
  • the invention consists of a hydraulic control system for parallel linkage oftool holders arranged on control arms actuated, for example, by means of hydraulic control cylinders, preferentially on cranes, loaders or the like, comprising a hydraulic cylinder mechanically coupled between the toolholder and the control arms and characterized chiefly in that the control units for the control arms are allotted a hydraulic valve, comprising a supervisory unit which detects the movements of the control arms, the supervisory unit being arranged so as to permit the passage of fluid to a regulating unit allotted to the hydraulic valve in dependence on the direction of movement of the control arms, and the regulating unit is arranged to assume a first position for the passage of fluid on movement of the control arms in one direction under the influence ofthe fluid to one side of the hydraulic cylinder and to assume a second position for passage of fluid to the other side of the hydraulic cylinder on movement of the
  • a Bowden cable or the like be arranged in such a way that one end of the Bowden cable wire is coiled up on a pulley rigidly connected to the toolholder, while the other end of the wire is taken to the supervisory unit via a pulley located at the pivoting axis of the booms on the machine.
  • the wire of the Bowden cable is coiled up on the pulley at the pivoting axis of the booms, whereby the wire, preferably against the ac tion of a spring, moves the supervisory unit a certain distance in the hydraulic valve.
  • communications are opened between different channels in the hydraulic valve in such a way that the regulating unit is brought into action, with the result that the hydraulic cylinder of the toolholder is supplied with fluid for rotation of the toolholder, and so the tool, to the desired position.
  • FIG. 1 shows a tractor with bucket attachment equipped with a device according to the invention
  • FIG. 2 shows a hydraulic valve according to the invention
  • FIG. 3 is a schematic diagram of the hydraulic connections between the hollow screws 2832 of the hydraulic valve [2 of FIG. 2 and the hydraulic cylinders 5 and I4 and control valve [0.
  • FIG. 1 shows a tractor equipped with a bucket attachment comprising booms 2 and a toolholder 3 on which is a bucket 4.
  • the booms are raised and lowered by means of hydraulic cylinders 5, the booms pivoting around a shaft 6.
  • the control cylinders 5 are actuated from a control valve 10 by means of levers It.
  • the bucket attachment is shown in two positions, a lowered position 2, 3, 4, S and raised position 2 3 4 5 With the tool 4 at a given angle to the ground, accordingly, the booms 2, (2') and the tool holder 3, (3' assume different angles to one another depending on the positions of the booms.
  • a hydraulic valve I2 from which fluid pressure lines 13 run to a hydraulic cylinder [4 between the boon is Z'and the toolholder 3. Furthermore, for transmission of the movements of the booms 2 and of the angle at every instant between the booms 2 and the toolholder 3 to the hydraulic valve 12 there is a Bowden cable 9 between the toolholder 3 and the hydraulic valve 12.
  • the wire l5 of the Bowden cable 9 is coiled up at one end on a pulley 8 fixed to the toolholder 3 and at its other end, via a pulley 7 located on the shaft 6 of the booms 2, is fixed to a supervisory unit in the hydraulic valve 12.
  • the wire 15 may, if necessary, be taken over an additional pulley in order to obtain a suitabae direction in relation to the supervisory unit.
  • the wire ofthe Bowden cable 9 is coiled up round the pulley 7. If the angle between the booms 2 and the toolholder 3 remains constant during this movement, the position of the wire 15 at the toolholder is fixed, so that the wire 15 actuates the supervisory unit in such a way that the latter is pulled in the direction out from the hydraulic valve.
  • FIG. 2 shows the various parts of the hydraulic valve [2 in detail.
  • the valve contains, as mentioned, a supervisory unit having a control rod 16 passing through most ofthe valve and, on the control rod, slotted clamping sleeves l8, 18', which are at least partly tapered.
  • the supervisory unit also comprises a control plunger 17 which, by means of tapered shoulders 52, 52', is arranged to engage with the tapered surfaces of the clamping sleeves l8, [8,
  • the clamping sleeves l8, [8' are kept apart by the action of a compression spring 19.
  • At one end of the control rod 16 there is a supporting washer 23 against which rests one end of a return spring 22, the other end of which rests against a stop washer bearing on a shoulder in the valve housing.
  • control rod [6 At the other end of the control rod [6 is a second stop washer 20'.
  • the end of the control rod [6 projecting from the valve housing is designed to be connected to the wire 15 of the Bowden cable. Furthermore the idle position of the control rod 16 relative to the valve housing is adjustable with a trimming screw 24.
  • the hydraulic valve also comprises a regulating unit consist ing of a regulating plunger 25 having a hole passing through it axially. At one end of the plunger 25 is a throttling disc 26 and at its other end a spring 27.
  • the hydraulic valve has also a number of fluid channels and five hollow screws 28, 29, 30, 31, 32 passing through the valve housing for connection both to the control valve 10 of the control cylinders 5 and to leads running to the control cylin ders 5 and the hydraulic cylinder 14.
  • the hydraulic valve functions as follows.
  • a chamber 40 around the control plunger 16 in the hydraulic valve 12 is thereby placed in open communication via a slot 43 in the control plunger with another chamber 39 around the control plunger 17.
  • a channel 35 leading from chamber 53 around the regulating plunger 25 to chamber 39 some of the return fluid is thereby led via chambers 39 and 40 and a channel to a chamber 56 at the other end of the regulating plunger 25.
  • the fluid is thereby passed through the throttling disc 26 under a certain pressure, the throttling producing a pressure dif ference between the two sides of the throttling disc.
  • the regulating plunger 25 is thereby moved against the action of spring 27.
  • the communication between chambers 53 and S4 is thus closed, while a communication is opened between chamber 53 and another chamber 55.
  • Return fluid from the control cylindcrs 5 can then freely flow into the hollow screw 31 and thereafter through one of leads 13 to the hydraulic cylinder 14.
  • Return fluid from the hydraulic cylinder 14 can either be led via the hollow screw 32 and through channels not shown in the drawing to the hollow screw 30 for return fluid or via a differential piston valve, for example of the type described in our Swedish Pat. and substitute therefor application No. 6614/65 which corresponds to US, Pat. No. 3,438,307, back to the pressure side of the hydraulic cylinder 14.
  • the control fluid entering the regulating plunger through the throttling disc 26 is led off through holes 60 in the regulating plunger 25 into channel 59 leading to a chamber 48 and to the hollow screw 30 for removal of return fluidv
  • the angle between the tool holder 3 and the booms 2 changes and the wire 15 is continuously uncoiled from pulley 8. This uncoiling is compensated by a continuous coiling up of the wire on pulley 7. If the angle between the toolholder 3 and the boom 2 becomes too large, the wire slackens, the result being that the supervisory unit is forced into the valve housing under the action of the return spring 22.
  • the pressure difference between the two sides of the throttling disc 26 thereby produces a movement of the regulating plunger 25 against the action of spring 27, which is sufficient to open a communication between chamber 54 and another chamber 58 around the regulating plunger in the valve housing.
  • the distance between chambers 54 and 58 is rather larger than between chambers 53 and 54. in the inner position of the regulating plunger, accordingly, a communication is open between chambers 54 and 58, whereas the communciations between chambers 53 and 54 and between chambers 55 and 53 closed.
  • the pressure fluid through the hollow screw 28 can then not flow into chamber 53 but is led entirely via chamber 58 out into a channel 50 leading from the latter to hollow screw 32.
  • a nonrcturn valve 51 is provided in the valve housing chamber 48 which communicates with hollow screws 30 for return of hydraulic fluid to the control valve 10 and channel 35.
  • the nonreturn valve 51 opens and return fluid flows out chamber 48 and control valve via channel 35, chamber 53 and channel 34 to control cylinders 5.
  • the wire of the Bowden cable 9 is uncoiled from pulley 8, with the result that the wire is slackened and that the control rod l6 is forced to its innermost position in the valve housing under spring ac tion.
  • control plunger [7 is then in a position such that chamber 37 communicates with chamber 38 and therefore with channel 49.
  • the tool On a downward movement of the booms 2 the tool is immediately bent up, the bending-up movement continuing until the wire 15 has been coiled round pulley 8 so far that the wire is tensioned sufficiently to pull the control rod 16 slightly out of the valve housing.
  • the trimming screw 24 the innermost position of the control rod 16 can be regulated, which affects also the length of wire which, after tilting of tool 4, must be coiled around pulley 8 before the wire is tensioned. In this way it is possible to regulate the angular position to which the tool 4 is returned after tilting.
  • stop washers 20, 20' and a strain-relieving sleeve 21 are also stop washers 20, 20' and a strain-relieving sleeve 21.
  • the function of these is to permit trimming with the trimming screw 24 and to render the valve inoperative in the event that the control rod is subjected to too great a movement owing to a fault. If, for example, the control rod is pulled violently in the direction out of the valve housing, the strain-relieving sleeve 21 is brought up against the stop washer 20' and thus brings the slotted clamping sleeve 18 out of engagement with the shoulder 52. The control rod is thus rendered freely movable in the control plunger 17.
  • the clamping sleeve [8' can be taken out of engagement with the shoulder 52' via the stop washer 20 in the event, for example, that the trimming screw 24 is unscrewed too far from the valve housing.
  • Hydraulic control system for producing parallel linkage of a toolholder located, for example, on control arms actuated by means of hydraulic control cylinders, preferentially for cranes, loaders or the like, comprising a hydraulic cylinder mechanically coupled between the toolholder and the control arms, characterized in that the control units for the control arms are allotted a hydraulic valve containing a supervisory unit detecting the movements of the control arms and, in dependence on the direction of movement of the control arms, permitting the passage of fluid to a regulating unit allotted to the hydraulic valve, the regulating unit assuming a first position for the passage of fluid to one side of the hydraulic cylinder on movement of the control arms in one direction under the influence of said fluid and a second position for passage of fluid to the other side of the hydraulic cylinder on movement of the control arms in the opposite direction.
  • Hydraulic control system characterized in that the fluid let through by the supervisory unit to the regulating unit consists of at least a part of the fluid of the control cylinders, preferentially the return fluid.
  • Hydraulic control system characterized in that the fluid let through by the regulating unit to the hydraulic cylinder consists of at least a part of the fluid of the control cylinders.
  • Hydraulic control system according to claim 3, charac terized in that the fluid let through by the regulating unit to the hydraulic cylinder on actuation of the toolholder in one direction against a force acting upon the toolholder carrying the tool consists of the pressure fluid of the control cylinders and, on actuation of the toolholder in the opposite direction, consists ofthe return fluid of the control cylinders.
  • Hydraulic control system wherein a shaft is operatively mounted on each of said control arms and said toolholder, said control system characterized in that the supervisory unit is designed to be actuated by movements of the control arms via a Bowdcn cable or the like, the wire of which passes over pulleys located on the shaft of the control arms and on the shaft of the toolholder.
  • Hydraulic control system characterized in that the control unit contains a control plunger detachably located on and concentric with a control rod and preferably spring-loaded.
  • Hydraulic control system further comprising a detachable fitting connected to said control plunger of said control rod, characterized in that the detachable fitting of the control plunger to the control rod is comprised of slotted clamping sleeves on the control rod which have outer tapered shoulders for engagement with inner tapered shoulders in the control plunger.
  • Hydraulic control system characterized in that the supervisory unit has a trimming screw for adjustment of one limit position of the control unit, thereby permitting, within certain limits, optional parallel linkage angles to which the toolholder is returned after tilting of the tool.
  • Hydraulic control system characterized in that the regulating unit consists of a plunger, preferably acted upon by a spring, having at one end a hole passing axially through it and throttled by a disc.
  • Hydraulic control system characterized in that the hydraulic valve has hollow screws passing through it for pressure fluid and return fluid to and from the control cylinders of the control arms and the hydraulic cylinder of the toolholder to permit manual a justment of the positions of control arms as well as toolholder, said hollow screws within the hydraulic valve having bushings leading to channels in the hydraulic valve.
  • Hydraulic control system characterized in that, between channels for return fluid in the hydraulic valve and channels leading to one side ofthe control cylinders, there is a nonreturn valve for the passing of fluid from the return channels to the control cylinders on movement of the control arms in a direction essentially coinciding with the direction ofa force acting upon the tool.
  • Hydraulic control system characterized in that the hydraulic cylinder of the toolholder is allotted to a differential piston valve for transmission of fluid from the suction side to the pressure side of the hydraulic cylinder during movement of the tool in a direction essentially coinciding with the direction of a force acting upon the tool.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)
US829655A 1968-06-06 1969-06-02 Hydraulic control system Expired - Lifetime US3592107A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE7645/68A SE322469B (fi) 1968-06-06 1968-06-06

Publications (1)

Publication Number Publication Date
US3592107A true US3592107A (en) 1971-07-13

Family

ID=20271916

Family Applications (1)

Application Number Title Priority Date Filing Date
US829655A Expired - Lifetime US3592107A (en) 1968-06-06 1969-06-02 Hydraulic control system

Country Status (3)

Country Link
US (1) US3592107A (fi)
GB (1) GB1275636A (fi)
SE (1) SE322469B (fi)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2183004A1 (fi) * 1972-05-02 1973-12-14 Int Harvester Co
US4715265A (en) * 1983-08-06 1987-12-29 Achim Graul Process and apparatus for vibratory operation of a working piston, in particular for active working tools
CN109715548A (zh) * 2016-09-16 2019-05-03 专业工具产品有限责任公司 用于变速器千斤顶鞍座的可调节定位臂
US10352019B2 (en) * 2017-05-25 2019-07-16 Kubota Corporation Front loader and work machine

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2811265A (en) * 1956-02-07 1957-10-29 Mixermobile Manufacturers Inc Loader
US2914202A (en) * 1957-09-16 1959-11-24 Mixermobile Manufacturers Inc Loader vehicle
US3032215A (en) * 1958-08-29 1962-05-01 Deere & Co Loader bucket leveling control
US3265229A (en) * 1963-12-02 1966-08-09 Massey Ferguson Inc Automatic bucket positioning mechanism

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2811265A (en) * 1956-02-07 1957-10-29 Mixermobile Manufacturers Inc Loader
US2914202A (en) * 1957-09-16 1959-11-24 Mixermobile Manufacturers Inc Loader vehicle
US3032215A (en) * 1958-08-29 1962-05-01 Deere & Co Loader bucket leveling control
US3265229A (en) * 1963-12-02 1966-08-09 Massey Ferguson Inc Automatic bucket positioning mechanism

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2183004A1 (fi) * 1972-05-02 1973-12-14 Int Harvester Co
US4715265A (en) * 1983-08-06 1987-12-29 Achim Graul Process and apparatus for vibratory operation of a working piston, in particular for active working tools
CN109715548A (zh) * 2016-09-16 2019-05-03 专业工具产品有限责任公司 用于变速器千斤顶鞍座的可调节定位臂
US10352019B2 (en) * 2017-05-25 2019-07-16 Kubota Corporation Front loader and work machine

Also Published As

Publication number Publication date
GB1275636A (en) 1972-05-24
SE322469B (fi) 1970-04-06

Similar Documents

Publication Publication Date Title
US3938669A (en) Hydraulic circuit for a pipelayer
US4679336A (en) Earth moving machine
US3871527A (en) Ram tensioning device
US3371799A (en) Telescopic boom angle control system
US4236695A (en) Sea swell compensation
US3990583A (en) Device for controlling the boom elevation of a side crane
US3776518A (en) Winch and control means therefor
US3690387A (en) Boom rotation brake release means for derricks
US3592107A (en) Hydraulic control system
US2249947A (en) Power transmission
US4223554A (en) Hoist test stand
US3785503A (en) Boom control mechanism for tractors or the like
US3481251A (en) Machine with hydraulic boom
US3516433A (en) Device for winding flexible tubing carrying fluid under pressure
US2879612A (en) Hydraulic drive for ditcher conveyor
US2966752A (en) Cranes
US2437466A (en) Hydraulic hoisting mechanism
GB809149A (en) Improvements in or relating to hydraulic operation of overhead crane carriages
US3241461A (en) Hydraulic control system
US2689053A (en) Hoisting apparatus
US3893572A (en) Systems for operating and controlling hydraulically driven winches, hoists, windlasses and the like
US4598829A (en) Hydraulic circuit for crane
JPH0442320B2 (fi)
US3601259A (en) Crane construction
US3499286A (en) Controllable hydraulic power unit