EP0597657A1 - Système de contrôle pour ensemble piston et cylindre - Google Patents

Système de contrôle pour ensemble piston et cylindre Download PDF

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Publication number
EP0597657A1
EP0597657A1 EP93308912A EP93308912A EP0597657A1 EP 0597657 A1 EP0597657 A1 EP 0597657A1 EP 93308912 A EP93308912 A EP 93308912A EP 93308912 A EP93308912 A EP 93308912A EP 0597657 A1 EP0597657 A1 EP 0597657A1
Authority
EP
European Patent Office
Prior art keywords
piston
speed
cylinder
maximum permitted
cylinder assembly
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.)
Withdrawn
Application number
EP93308912A
Other languages
German (de)
English (en)
Inventor
Brian Clifton
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.)
Fermec Manufacturing Ltd
Original Assignee
Fermec Manufacturing Ltd
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 Fermec Manufacturing Ltd filed Critical Fermec Manufacturing Ltd
Publication of EP0597657A1 publication Critical patent/EP0597657A1/fr
Withdrawn legal-status Critical Current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
    • 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
    • F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
    • F15B11/046—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed depending on the position of the working member
    • F15B11/048—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed depending on the position of the working member with deceleration control
    • 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
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/327—Directional control characterised by the type of actuation electrically or electronically
    • 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
    • F15B2211/35—Directional control combined with flow control
    • 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
    • F15B2211/63—Electronic controllers
    • F15B2211/6303—Electronic controllers using input signals
    • F15B2211/6336—Electronic controllers using input signals representing a state of the output member, e.g. position, speed or acceleration
    • 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
    • F15B2211/63—Electronic controllers
    • F15B2211/6303—Electronic controllers using input signals
    • F15B2211/6346—Electronic controllers using input signals representing a state of input means, e.g. joystick position
    • 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
    • F15B2211/665—Methods of control using electronic components
    • F15B2211/6654—Flow rate control
    • 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
    • F15B2211/7052—Single-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
    • F15B2211/705—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
    • F15B2211/75—Control of speed of the 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
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/755—Control of acceleration or deceleration of the output member

Definitions

  • This invention relates to a piston and cylinder assembly control system, in particular a system for controlling the speed of one or more pistons in a piston and cylinder assembly.
  • Such piston speed control systems are used, for example, in tractor mounted loader and digger operating systems.
  • the invention therefore provides a piston and cylinder assembly control system including:
  • the piston and cylinder assembly may be double acting or single acting. If double acting it may comprise a double acting ram or two opposed single acting rams.
  • the piston means may be a single piston reciprocating in a single cylinder or two pistons reciprocating in respective cylinders.
  • the invention provides the advantage that not only are very sudden stresses as a piston arrives at the end of a cylinder avoided but also stresses experienced by the assembly, and the part driven by the assembly, as the piston decelerates can be controlled. Such stresses can be kept to a minimum if, for the majority of the piston travel, the maximum permitted piston speed at any position reduces as a function of the square of the distance to the stopping position. However, to provide a jerk free piston halt, for the final portion of piston travel the maximum permitted piston speed may reduce as a function of the distance to the stopping position.
  • the system may determine the maximum permitted piston speed at any position by using a look-up table in the control unit, or by calculation according to a predetermined relationship.
  • the actual piston speed at any point may be obtained by differentiation of the piston position signals or from separate speed sensor means.
  • the position sensing means providing signals indicative of the position of the piston within the cylinder may sense the position of the part driven by the piston and cylinder assembly and the control unit may be arranged appropriately such that the signals are converted to piston position signals. Alternatively the position sensing means may directly sense the position of the piston within the cylinder.
  • a tractor front loader has a loader tower 10 supported on the chassis (not shown).
  • a loader beam 12 is pivotally connected to the upper end of the loader tower 10 at one end and has a bucket 14 pivotally connected to its other end.
  • the beam 12 and bucket 14 are moved about their respective pivot points by means of beam and bucket double acting hydraulic actuators 16 and 1 8 respectively.
  • the actuators 16 and 18 each comprise a piston 16a, 18a and a cylinder 16b, 18b.
  • the supply to and exhaust of hydraulic fluid from the actuators 16 and 18 is controlled by solenoid operated valves 20 and 22 respectively.
  • the valves 20 and 22 receive pressurised fluid from pump 24 and exhaust fluid to reservoir 26.
  • Valve operating solenoids 20a and 22a receive control signals from control unit 28 via lines 30 and 32.
  • Movements of the beam 12 and bucket 14 about their respective pivot points are monitored by beam and bucket position sensors 34 and 36 respectively in the form of rotary potentiometers.
  • the sensors 34, 36 send position signals to the control unit 28 via lines 38 and 40.
  • the sensors 34, 36 are shown located at the beam and bucket pivot points they may be located adjacent to the pivot points with appropriate links or struts to ensure they sense the movements correctly.
  • the control unit 28 is connected to control lever assembly 42 via lines 44.
  • the control lever assembly 42 includes a manually operable control lever 42a mounted for pivotal movement about two perpendicular axes in the X and Y directions shown in Figure 1, the control lever 42a being located appropriately for operation by the right hand.
  • the control unit 28 generates the control signals in response to signals received from the control lever assembly 42, representing movement of control lever 42a, and from the position sensors 34 and 36 as described later.
  • the lever 42a is pivotted in the Y direction to command movement of the beam 12. Initially the piston 1 6a accelerates towards a speed proportional to the pivot angle of the lever 42a. However, every 5ms the control unit 28 performs a calculation and checking routine to ascertain whether the speed commanded by the lever 42a should be modulated, and if modulation is necessary generates appropriately modulated control signals for the solenoid 20a.
  • the control unit 28 receives sensed angular position signals from the sensor 34 along line 38.
  • the angular position signals are used in combination with the known end point of travel of the beam to calculate the angular distance to the end point. This angular distance is used as an input value for a maximum permitted piston speed look-up table in the control unit 28. Thus the angular distance is converted to a linear speed.
  • the control unit 28 also calculates the actual speed of the piston 16a by conversion and differentiation of the angular position signals.
  • the actual speed of the piston 16a is then compared with the maximum permitted piston speed for the distance to the end of travel and, if the maximum permitted speed is exceeded, the control unit 28 modulates the control signal for the solenoid 20a to reduce the fluid flow rate to and from the cylinder 1 6b such that the piston speed is reduced below the maximum permitted speed.
  • the exact manner of control of the flow rate to and from the cylinder 16b depends on a number of factors including headside/rodside flow, gravity and inertia of the load.
  • solid curve 50 illustrates the maximum permitted piston speed versus distance to piston stopping point curve appropriate for the beam actuator 16 during raising of the beam 12 and for the bucket actuator 18 during crowding of the bucket 14.
  • region A the maximum permitted piston speed is proportional to the square of the distance to the stopping point.
  • region B the maximum permitted piston speed in region B is proportional to the distance to the stopping point.
  • Dashed curve 52 illustrates an example of actual speed attained by the piston 16a or 18a. In portion A1 of region A curve 52 is straight and below the curve 50 indicating that the speed commanded by the lever 42a is below the maximum permitted piston speed.
  • the dashed curve 52 joins the solid curve 50 indicating that at that point the speed commanded by the lever 42a has become the maximum permitted piston speed and the control unit has begun to modulate the control signals for the solenoid 20a or 22a and thus the oil flow to and from the cylinder 16b or 18b.
  • the change of oil flow into cylinder 16b or 18b with time for the above example is illustrated by curve 54.
  • portion P1 corresponding to A1 of Figure 2
  • the oil flow is constant, and the speed of the piston 16a or 18a is constant.
  • portion P2 corresponding to A2 of Figure 2
  • the oil flow reduces at a constant rate and the deceleration of the piston 16a or 18a is constant.
  • region Q the oil flow reduces exponentially to provide a no-jerk stop at the stopping position.
  • the maximum permitted piston speed curve in these cases is illustrated by the solid line 56 in Figure 4.
  • the curve 56 is the same as the curve 50 until at point T it falls to one third of the maximum permitted piston speed, as shown over portion C of the curve 56. No further slowing of the piston takes place, thus the remaining travel of the piston occurs at a constant speed, as shown over portion D of the curve 56.
  • time outs are imposed.
  • the control unit 28 ceases to modulate the flow of oil at point T it sets a time delay, for instance 0.5s or 1.0s, after which the flow of oil to the respective cylinder 16b or 18b is cut off completely.
  • the system of the invention is not limited to use in tractor front loaders as described above. It is, for instance, particularly applicable for use on the backhoes of tractor digger loaders, to control piston speed during movement of the boom, dipper and bucket or other attachment.
  • the stopping position used by the system control unit in the calculation and checking routine need not be the end of the piston stroke. If the vehicle or machine to which the system is fitted also has a control system allowing other end stops to be set, for instance backhoe dig and dump positions, the piston may be slowed to a stop at these positions instead of at the end of the cylinder.
  • the system is not limited to the control of piston speed as the piston approaches a stopping point.
  • the maximum permitted piston speed envelope can be of any form required for a particular application. There may, for instance, be applications where for safety reasons a piston must travel slowly during a mid portion of its travel as well as slowing to a stop at the ends.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)
EP93308912A 1992-11-13 1993-11-08 Système de contrôle pour ensemble piston et cylindre Withdrawn EP0597657A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9223827 1992-11-13
GB929223827A GB9223827D0 (en) 1992-11-13 1992-11-13 System for controlling the speed of a piston in a piston and cylinder assembly

Publications (1)

Publication Number Publication Date
EP0597657A1 true EP0597657A1 (fr) 1994-05-18

Family

ID=10725037

Family Applications (1)

Application Number Title Priority Date Filing Date
EP93308912A Withdrawn EP0597657A1 (fr) 1992-11-13 1993-11-08 Système de contrôle pour ensemble piston et cylindre

Country Status (2)

Country Link
EP (1) EP0597657A1 (fr)
GB (2) GB9223827D0 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007054123A1 (fr) * 2005-11-10 2007-05-18 Volvo Construction Equipment Holding Sweden Ab Chargeuse
WO2007086783A1 (fr) * 2006-01-26 2007-08-02 Volvo Construction Equipment Ab Procédé pour commander le mouvement d'un élément de véhicule
US7591090B2 (en) 2005-08-02 2009-09-22 Volvo Vompact Equipment Sas Civil engineering loading machine
WO2016014141A2 (fr) 2014-07-24 2016-01-28 Google Inc. Contrôleur de limite d'actionneur
CN105386482A (zh) * 2006-01-26 2016-03-09 沃尔沃建筑设备公司 用于控制车辆部件移动的方法
EP4279666A3 (fr) * 2016-06-09 2024-02-21 Husqvarna AB Agencement et procédé améliorés pour faire fonctionner un vérin hydraulique

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19842337A1 (de) * 1998-09-16 2000-03-23 Mannesmann Vdo Ag Betätigungseinrichtung für ein Verdeck eines Cabrios
EP2505722B1 (fr) * 2010-03-15 2014-05-14 Komatsu, Ltd. Dispositif de commande pour machine de travail sur véhicule de construction et procédé de commande

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2125982A5 (fr) * 1971-02-18 1972-09-29 Rank Organisation Ltd
DE2261514A1 (de) * 1971-12-17 1973-06-20 Rank Organisation Ltd Servomechanismus
EP0022105A1 (fr) * 1979-06-20 1981-01-07 Akermans Verkstad AB Dispositif pour diminuer la vitesse d'un piston dans un cylindre
FR2565638A1 (fr) * 1984-06-11 1985-12-13 Nippon Joucomatic Co Ltd Verin pneumatique comportant un mecanisme de deceleration
WO1987004220A1 (fr) * 1985-01-07 1987-07-16 A^oKERMANS VERKSTAD AB Procede permettant de reduire la vitesse du piston, surtout dans un ensemble de pistons/cylindres d'une pelle mecanique, et dispositif pour la mise en oeuvre du procede

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8900774D0 (en) * 1989-01-13 1989-03-08 Ml Eng Plymouth Vehicle movement control

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2125982A5 (fr) * 1971-02-18 1972-09-29 Rank Organisation Ltd
DE2261514A1 (de) * 1971-12-17 1973-06-20 Rank Organisation Ltd Servomechanismus
EP0022105A1 (fr) * 1979-06-20 1981-01-07 Akermans Verkstad AB Dispositif pour diminuer la vitesse d'un piston dans un cylindre
FR2565638A1 (fr) * 1984-06-11 1985-12-13 Nippon Joucomatic Co Ltd Verin pneumatique comportant un mecanisme de deceleration
WO1987004220A1 (fr) * 1985-01-07 1987-07-16 A^oKERMANS VERKSTAD AB Procede permettant de reduire la vitesse du piston, surtout dans un ensemble de pistons/cylindres d'une pelle mecanique, et dispositif pour la mise en oeuvre du procede

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7591090B2 (en) 2005-08-02 2009-09-22 Volvo Vompact Equipment Sas Civil engineering loading machine
WO2007054123A1 (fr) * 2005-11-10 2007-05-18 Volvo Construction Equipment Holding Sweden Ab Chargeuse
CN105386482A (zh) * 2006-01-26 2016-03-09 沃尔沃建筑设备公司 用于控制车辆部件移动的方法
US8560181B2 (en) 2006-01-26 2013-10-15 Volvo Construction Equipment Ab Method for controlling a movement of a vehicle component
CN101336345B (zh) * 2006-01-26 2015-11-25 沃尔沃建筑设备公司 用于控制车辆部件移动的方法
WO2007086783A1 (fr) * 2006-01-26 2007-08-02 Volvo Construction Equipment Ab Procédé pour commander le mouvement d'un élément de véhicule
EP1982075A4 (fr) * 2006-01-26 2017-03-15 Volvo Construction Equipment AB Procédé pour commander le mouvement d'un élément de véhicule
CN105386482B (zh) * 2006-01-26 2019-04-09 沃尔沃建筑设备公司 用于控制车辆部件移动的方法
WO2016014141A2 (fr) 2014-07-24 2016-01-28 Google Inc. Contrôleur de limite d'actionneur
EP3172450A4 (fr) * 2014-07-24 2018-04-11 Google LLC Contrôleur de limite d'actionneur
JP2019052760A (ja) * 2014-07-24 2019-04-04 ボストン ダイナミクス，インコーポレイテッド アクチュエータ限界コントローラ
US10550860B2 (en) 2014-07-24 2020-02-04 Boston Dynamics, Inc. Actuator limit controller
US10851810B2 (en) 2014-07-24 2020-12-01 Boston Dynamics, Inc. Actuator limit controller
EP4279666A3 (fr) * 2016-06-09 2024-02-21 Husqvarna AB Agencement et procédé améliorés pour faire fonctionner un vérin hydraulique

Also Published As

Publication number Publication date
GB2272541A (en) 1994-05-18
GB9322831D0 (en) 1993-12-22
GB9223827D0 (en) 1993-01-06

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