US3650425A - Bucket loader control system - Google Patents

Bucket loader control system Download PDF

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Publication number
US3650425A
US3650425A US45741A US3650425DA US3650425A US 3650425 A US3650425 A US 3650425A US 45741 A US45741 A US 45741A US 3650425D A US3650425D A US 3650425DA US 3650425 A US3650425 A US 3650425A
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US
United States
Prior art keywords
valve
curl
bucket
dump
automatic
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
US45741A
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English (en)
Inventor
Russell H Hallman
John B Keir
Lawrence J Patritto
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.)
Vickers Inc
Original Assignee
Sperry Rand Corp
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
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Publication of US3650425A publication Critical patent/US3650425A/en
Assigned to SPERRY CORPORATION reassignment SPERRY CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: SPERRY RAND CORPORATION
Assigned to VICKERS, INCORPORATED reassignment VICKERS, INCORPORATED ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: SPERRY CORPORATION A DE CORP.
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
    • E02F3/434—Control of dipper or bucket position; Control of sequence of drive operations for bucket-arms, front-end loaders, dumpers or the like providing automatic sequences of movements, e.g. automatic dumping or loading, automatic return-to-dig
    • 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
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • 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
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/2053—Type of pump
    • F15B2211/20538—Type of pump constant capacity
    • 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
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
    • 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
    • F15B2211/50—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
    • F15B2211/52—Pressure control characterised by the type of actuation
    • F15B2211/528—Pressure control characterised by the type of actuation actuated by fluid pressure
    • 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
    • F15B2211/55—Pressure control for limiting a pressure up to a maximum pressure, e.g. by using a pressure relief valve
    • 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
    • F15B2211/605—Load sensing circuits
    • F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
    • 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
    • F15B2211/635—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements
    • F15B2211/6355—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements having valve 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
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051—Linear output members
    • F15B2211/7053—Double-acting output 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
    • 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
    • F15B2211/783—Sequential control

Definitions

  • ABSTRACT A material handling bucket loader with hydraulic boom lifting and bucket curling has an automatic control for bucket curling during the loading operation to assure filling of the bucket.
  • the pressure developed in the boom lift system is utilized to open a normally closed curl valve when the load on the boom reaches a predetermined value which is manually adjustable.
  • Manual override of the automatic curl valve is achieved by sensing the flow which occurs when the manual curl valve is operated and by shifting a shuttle valve in response to such flow.
  • the object of the present invention is to provide an automatic bucket curling system which will curl the bucket simultaneously with the lifting of the boom in such a manner that the bucket will automatically start to curl when a predetermined but adjustable force is required to lift the boom.
  • the invention consists in a hydraulic control system for a bucket loader having a lift-lower valve with a cylinder controlled thereby to lift the bucket, and a curl-dump valve with a cylinder controlled thereby to curl or dump the bucket with the provision therein of an automatic, normally closed, curl valve connected in parallel with the curl-dump valve together with a means which form a pressure responsive actuator for the automatic curl valve and a connection from the lift-lower valve to that actuator for causing the bucket to curl automati cally when the load to be lifted reaches a predetermined amount.
  • FIG. 1 is a cross sectional view of an automatic curl valve incorporated in a preferred form of the present invention.
  • FIG. 2 is a cross sectional view of a selector valve also incorporated in a preferred form of the present invention.
  • FIG. 3 is a front view of the selector valve ofFlG. 2.
  • FIG. 4 is a schematic circuit drawing showing a preferred form of the present invention.
  • the bucket loader or tractor-shovel illustrated in FIG. 4 has the conventional front end bucket 12 mounted on a boom 14.
  • the conventional hydraulic means for operating the boom and bucket are indicated diagrammatically at the lift-lower cylinder 16 which is manually controlled through lines 18 and 20 by a lift-lower valve 22 with an anti-drop check valve 24 which receives pressure fluid from a pump 26 through the supply line 28 which is monitored by an overload relief valve 30.
  • the bucket 12 has the usual hydraulic operating system comprising the curl-dump cylinder 32 which is manually controlled through lines 34 and 36 by a curl-dump valve 38 having the anti-drop check valve 40 supplied from the line 28.
  • the line 28 extends in series through valves 38 and 22 to an unloading return line 42 going back to the reservoir 44 from which the pump 26 withdraws hydraulic fluid and to which the valves 22 and 38 are connected by return lines 46 and 48.
  • the present invention adds the automatic curl valve indicated by the dot-dash rectangle 50 and the selector valve indicated by the dot-dash rectangle 52 together with the appropriate connecting lines to the remainder of the system.
  • the automatic curl valve 50 is a normally closed four-way valve which is connected in parallel with curl-dump valve 38 to the cylinder 32 by the lines 5456. has an anti-drop check valve 58, a supply line 60 connected to the supply line 28 and a return line 62 going to the sump 44. Valve 50 may be opened against its bias spring 64 by a contro pressure delivered through a line 66.
  • the valve 50 is illustrated in detail in FIG. 1 where the body 68 has a main bore 70 receiving a sliding spool 72.
  • Four passages in the body 68 lead to the bore 70 and carry the numbers 54, 56, 60 and 62, they being extensions of the lines cor respondingly indicated in FIG. 4.
  • the bore 70 is closed at its ends by bushings 74 and 76 which form the terminals of lines 66 and 78 respectively.
  • Line 78 leads to the lowering end of the cylinder 16 via line 20.
  • Spool 72 has a through passage 80 which is in communication via a hole 82 with the return line 62 and also communicates with both ends of the bore 70 via restriction plugs 84 and 86.
  • FIG. 1 shows the valve 50 in its normally closed position with the spool 72 urged tothe left by the biasing spring 64.
  • the selector valve 52 is illustrated in FIGS. 2 and 3 wherein the body 88 contains three bores 90, 92 and 94 which are connected by a staggered passage 96 closed at its ends by ball plugs 98.
  • the left ends of the bores 90, 92 and 94 are provided with connections to lines 100, 102 and 104 respectively, while the right end of bore 92 has a line connection 106 leading from the side of the body 88.
  • Bore contains a spring loaded poppet 108 which may be manually opened or closed by means of a threaded knob 110 and lift pin 112.
  • Bore 92 contairis a shuttle valve 114 spring biased to the right.
  • shuttle valve 114 will shift to the left closing the staggered passage 96.
  • Bore 94 contains a spring loaded pressure responsive relief valve 116. Its pressure setting may be varied by means of a threaded knob 118 which adjusts the position of the tubular valve seat 120 and thus varies the compression of the spring 122.
  • the line which is the inlet line to the selector valve 52 leads from the downstream side of the anti drop check valve 24 in the lift-lower valve 22.
  • Line 102 leads from the downstream side of the anti-drop check valve 40 in the curl-dump valve 38.
  • Line 104 which is the output line from the selector valve 52, connects with line 66 of the automatic curl valve 50.
  • Line 106 connects at the upstream side of check valve 40.
  • a restricted shunt 124 not shown in'FIG. 2, extends between lines 102 and 106.
  • valve 22 In operation, the driver of the vehicle positions the boom and bucket as shown in FIG. 4 and crowds the same into the pile or bank from which material is to be loaded. As the crowding slows down or ceases completely, valve 22 is operated to lift the boom. The weight of the material in the bucket develops pressure in the line 18 which is transmitted through line 100 to the selector valve 52. With knob turned to the on position and valve 108 open, and with valve 38 in neutral position, this pressure acts on relief valve 116. Depending upon the adjustment of valve 116 and the density of the material being loaded, this pressure may open valve 116 and be transmitted through lines 104 and 66 to the left end of valve-50 in FIG. 1, to shift the spool 72 to the right. With the proper setting of the knob 118, which is readily determined by trial, the opening of valve 50 actuates the cylinder 32 in a direction to curl the bucket and as lifting and crowding continues, the bucket is filled for transport .and dump.
  • Dumping may take place in the usual manner by actuation of valve 38.
  • the bucket may be also curled under manual control at any time during the lift-load cycle by merely actuating the manual valve 38.
  • the flow which occurs through anti-drop check valve 40 creates a small pressure drop and this pressure drop is sensed through the lines 102 and 106 at the opposite ends of the shuttle valve 114.
  • This valve may be located either between the valves 108 and 116 as shown in FIG. 2, or beyond the valve 116 as shown in FIG. 4, and whenever it is actuated the passage between the inlet and outlet of selector valve 52 is closed. If at that time the automatic curl valve 50 is open, then this closure of shuttle valve 114 permits automatic curl valve 50 also to close.
  • the operator has. the continuing ability to override the automatic curl function at will and by the normal means and manner of exercising control of the bucket.

Landscapes

  • 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)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Loading Or Unloading Of Vehicles (AREA)
US45741A 1970-06-12 1970-06-12 Bucket loader control system Expired - Lifetime US3650425A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US4574170A 1970-06-12 1970-06-12

Publications (1)

Publication Number Publication Date
US3650425A true US3650425A (en) 1972-03-21

Family

ID=21939617

Family Applications (1)

Application Number Title Priority Date Filing Date
US45741A Expired - Lifetime US3650425A (en) 1970-06-12 1970-06-12 Bucket loader control system

Country Status (6)

Country Link
US (1) US3650425A (enExample)
JP (1) JPS528602B1 (enExample)
CA (1) CA923792A (enExample)
FR (1) FR2096246A5 (enExample)
GB (1) GB1334581A (enExample)
SE (1) SE390040B (enExample)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3966066A (en) * 1975-04-25 1976-06-29 Caterpillar Tractor Co. Hydraulic circuit
US4826474A (en) * 1987-12-14 1989-05-02 Butterworth Jetting Systems, Inc. Forklift apparatus for unloading articles from an elevated surface
EP1574474A3 (de) * 2004-03-13 2006-10-04 Deere & Company Hydraulische Anordnung

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3987920A (en) * 1975-06-23 1976-10-26 J. I. Case Company Self-leveling system for material handling implement
FR2489773A1 (fr) * 1980-09-11 1982-03-12 Connel Ltd F W Systeme hydraulique utilisable dans la combinaison d'un engin de travail avec un vehicule en particulier de remorquage
US4367673A (en) * 1981-01-09 1983-01-11 Dresser Industries, Inc. System and method for controlling the elevation of a boom hoist device
FR2938561A1 (fr) * 2008-11-20 2010-05-21 Mailleux Dispositif de remise a niveau automatique de l'outil d'un chargeur hydraulique monte sur un tracteur

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3494495A (en) * 1967-11-24 1970-02-10 Ford Motor Co Tractor mounted loader

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3339763A (en) * 1966-10-14 1967-09-05 Univ Oklahoma State Automatic back hoe control system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3494495A (en) * 1967-11-24 1970-02-10 Ford Motor Co Tractor mounted loader

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3966066A (en) * 1975-04-25 1976-06-29 Caterpillar Tractor Co. Hydraulic circuit
US4826474A (en) * 1987-12-14 1989-05-02 Butterworth Jetting Systems, Inc. Forklift apparatus for unloading articles from an elevated surface
EP1574474A3 (de) * 2004-03-13 2006-10-04 Deere & Company Hydraulische Anordnung

Also Published As

Publication number Publication date
GB1334581A (en) 1973-10-24
JPS528602B1 (enExample) 1977-03-10
FR2096246A5 (enExample) 1972-02-11
SE390040B (sv) 1976-11-29
DE2129007A1 (de) 1971-12-23
CA923792A (en) 1973-04-03
DE2129007B2 (de) 1977-07-07

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Legal Events

Date Code Title Description
AS Assignment

Owner name: SPERRY CORPORATION

Free format text: CHANGE OF NAME;ASSIGNOR:SPERRY RAND CORPORATION;REEL/FRAME:003794/0122

Effective date: 19790824

AS Assignment

Owner name: VICKERS, INCORPORATED TROY, MI A DE CORP

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST. EFFECTIVE NOVEMBER 2, 1983;ASSIGNOR:SPERRY CORPORATION A DE CORP.;REEL/FRAME:004337/0889

Effective date: 19831102

Owner name: VICKERS, INCORPORATED,MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SPERRY CORPORATION A DE CORP.;REEL/FRAME:004337/0889

Effective date: 19831102