EP1209365A2 - Procédé de contrôle d'un vérin, et machine agricole pour l'application du dit procédé - Google Patents

Procédé de contrôle d'un vérin, et machine agricole pour l'application du dit procédé Download PDF

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Publication number
EP1209365A2
EP1209365A2 EP01204041A EP01204041A EP1209365A2 EP 1209365 A2 EP1209365 A2 EP 1209365A2 EP 01204041 A EP01204041 A EP 01204041A EP 01204041 A EP01204041 A EP 01204041A EP 1209365 A2 EP1209365 A2 EP 1209365A2
Authority
EP
European Patent Office
Prior art keywords
chamber
piston
closing means
valve
fluid
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Withdrawn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
EP01204041A
Other languages
German (de)
English (en)
Other versions
EP1209365A3 (fr
Inventor
Jelle Fredo Oudemans
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.)
Lely Enterprises AG
Original Assignee
Lely Enterprises AG
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 Lely Enterprises AG filed Critical Lely Enterprises AG
Publication of EP1209365A2 publication Critical patent/EP1209365A2/fr
Publication of EP1209365A3 publication Critical patent/EP1209365A3/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Withdrawn legal-status Critical Current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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • 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
    • F15B2211/30505—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
    • F15B2211/30505—Non-return valves, i.e. check valves
    • F15B2211/30515—Load holding 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
    • F15B2211/3056—Assemblies of multiple valves
    • F15B2211/30565—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-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
    • F15B2211/321—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
    • F15B2211/30—Directional control
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/321—Directional control characterised by the type of actuation mechanically
    • F15B2211/325—Directional control characterised by the type of actuation mechanically actuated by an output member of the 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
    • F15B2211/50—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
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5153—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/625—Accumulators

Definitions

  • the invention relates to a method of controlling a control cylinder, preferably constituted by a hydraulic control cylinder, provided with a housing accommodating a piston with a piston rod, said piston dividing the housing into at least a first and a second chamber, while a fluid, such as e.g. oil, can be supplied to or discharged from the first and second chamber via apertures in the housing.
  • a control cylinder preferably constituted by a hydraulic control cylinder, provided with a housing accommodating a piston with a piston rod, said piston dividing the housing into at least a first and a second chamber, while a fluid, such as e.g. oil, can be supplied to or discharged from the first and second chamber via apertures in the housing.
  • Such a method of controlling a control cylinder is generally known.
  • first closing means that close a shut-off valve, so that the amount of fluid between the piston and the shut-off valve at that side of the piston that is opposite to the direction of movement of the piston, remains constant or almost constant, after which the piston is still further moved in the housing over a distance X in the direction of movement, X being greater than zero.
  • first closing means that close a shut-off valve
  • the piston of the relevant control cylinder can freely be moved over a distance X, which is advantageous for example when the control cylinder is used for bringing the machine from the transport position into the working position and the control cylinder can thus follow irregularities in the field without being blocked.
  • the method also comprises first closing means that are activated automatically. In the example of the mowing machine this has the advantage that the operator on the tractor needs not to decide himself on the activation of the closing means. Because the moment of activating the first closing means may vary with the machine used, the method also includes that the automatic activation of the first closing means is adjustable. According to again another method of the invention, it is also possible to determine, with the aid of registration means, the moment when the first closing means have to be activated.
  • the method also includes that, after the first closing means have been activated, via a first non-return valve, pressure is built up by the fluid in that chamber of the housing that is not in connection with the first shut-off valve, which chamber will be called hereinafter the second chamber, until a value has been reached that is greater than or equal to the opening pressure of second closing means that are in connection with the second chamber, after which the pressure built up in the second chamber flows away along the second closing means until a value has been reached that is lower than that of the opening pressure of the second closing means.
  • the piston with the piston rod one adjustable force in the first direction of movement.
  • the method also includes that, during building up of the pressure in the second chamber, pressure is applied by the fluid to an accumulator that is in connection with the second chamber.
  • an accumulator has the advantage that unexpected forces that are exercised on the piston and the piston rod can be absorbed in the accumulator while the pressure in the entire system is maintained.
  • the method also includes that, after the first closing means have been deactivated, the piston is moved in the second direction of movement over a greater distance than the distance X.
  • the deactivation of the first closing means By the deactivation of the first closing means the blocking in the control cylinder of the piston is removed.
  • the method also includes that the deactivation of the first closing means takes place manually or automatically.
  • the automatic deactivation of the first closing means can be controlled directly or indirectly by the movement of the piston in the housing. In the situation that the control cylinder is applied in a mowing machine or an other agricultural implement, after the deactivation of the first closing means it is thus possible to bring the machine e.g. from the working position into the transport position.
  • the invention also relates to an agricultural machine, adapted for applying the method as described above and provided with at least one working member which, by means of a control cylinder comprising two chambers with a fluid, separated by a movable piston, can be brought into a first transport position corresponding with a first piston position in which a first chamber contains a first amount of fluid, or into one or more working positions each corresponding with a further piston position in which the first chamber contains a further amount of fluid that is larger than the first amount, characterized in that the machine is provided with means that are adapted, when the working member is in one of the working positions, for automatically controlling the amount of fluid in the first chamber in such a manner that the working member cannot reach the transport position. According to a further inventive feature, the means keep the amount of fluid in the first chamber almost constant.
  • the invention further also relates to an agricultural machine provided with a control cylinder and provided with a housing accommodating a piston with a piston rod, said piston dividing the housing into at least a first and a second chamber, and with first closing means with a first shut-off valve, said agricultural machine being adapted for applying the method as described above.
  • the first shut-off valve is designed as a non-return valve or a multistage cock or a slide valve or a valve. It will be obvious that in that case the multistage cock produces the same effect as the non-return valve.
  • the first shut-off valve may be designed as a cock.
  • the agricultural machine comprises second closing means as described in the above-mentioned method.
  • the second closing means comprise at least one non-return valve.
  • the second closing means may have a non-return valve or a cock or a slide valve with a controllable opening pressure.
  • the second closing means may also comprise other multistage cocks or slide valves or valves known per se with the aid of which the same effect is obtained.
  • the second chamber is connected with an accumulator.
  • the second closing means comprise a multistage cock or a slide valve or a valve that is adapted for making the fluid flow from the second chamber in a certain position of the cock.
  • the multistage cock is in connection with a throttle valve and/or is included in a smaller line than the line that is in connection with the first chamber.
  • the aforementioned registration means comprise a mechanical switch.
  • the aforementioned registration means may also comprise a clinometer.
  • the control cylinder is designed as a hydraulic control cylinder. The above-mentioned method and control cylinder can in particular be applied with a mowing machine to be coupled to the three-point lifting hitch of a tractor.
  • Figure 1 shows a control diagram for controlling a control cylinder 1, preferably constituted by a hydraulic control cylinder, provided with a housing 2 accommodating a piston 3 with a piston rod 4.
  • the piston 3 divides the housing into a first chamber 5 and a second chamber 6.
  • a fluid can be brought into the first chamber 5 or flow away therefrom.
  • a second aperture 9 and a second line 10 the fluid can flow respectively into and from the second chamber 6.
  • first closing means 11 comprising in the present embodiment a shut-off valve 12 that is designed as a cock.
  • the second line 10 splits up into a third line 13 and a fourth line 14 which join later to form the second line 10.
  • a first non-return valve 15 allowing the fluid to pass from a source 16 in the direction of the second chamber 6.
  • an accumulator with a manometer 18.
  • second closing means 19 along which the fluid can only flow from the chamber 6 to the source 16.
  • the second closing means 19 are preferably designed as closing means with a controllable opening pressure.
  • the second closing means 19 are constituted by a non-return valve with controllable opening pressure.
  • the control cylinder 1 can e.g. be applied to a mowing machine 20 with a cutter bar 27 as shown in Figure 6. From the source 16 fluid can be supplied to respectively discharged from the first line 8 and the second line 10 by means of third closing means 26.
  • Figure 2 and Figure 3 show a second embodiment of a control cylinder 1 with a control diagram related thereto in which parts corresponding with those of the first embodiment are indicated by the same reference numerals.
  • the first closing means 11 comprise a slide valve 21 as shown in Figure 2.
  • the slide valve 21 is constituted by a 6/2-valve that is mechanically controllable against spring pressure.
  • the first closing means 11 further comprise a shut-off valve 12 included in the first line 8 and designed as a non-return valve.
  • a fluid can be supplied to or discharged from the source 16.
  • a second closing element 25 it is possible in an analogous manner to supply or discharge the fluid from the source 16 through the fifth line 22, while by means of a third closing element 26 it is also possible to supply and discharge the fluid from the source 16 through the second line 10.
  • the control cylinder 1 is applied to an agricultural machine, it is possible to design the first and second closing element 24, 25 as a double-acting valve and the third closing element 26 as a single-acting valve.
  • the same closing elements are applied as in the second embodiment, however with this distinction that to the first line 8 only one first closing element 24 is connected.
  • control cylinder 1 of the second embodiment The function of the control cylinder 1 of the second embodiment will now be explained in further detail with reference to Figure 6 in which the control cylinder 1 is included in a mowing machine 20 provided with a cutter bar 27 and being able to be coupled with a (non-shown) tractor by means of a coupling trestle 28.
  • the cutter bar 27 is pivotable from a transport position indicated by the reference numeral 29 to a working position indicated by the reference numeral 30. In the transport position 29 the cutter bar 27 encloses an angle of approximately 120° with the horizontal.
  • the transport position 29 shown in Figure 6 corresponds with the position shown in Figure 2 of the piston 3 and the first and second closing means 11, 19.
  • the second closing element 25 is controlled, so that the fluid flows from the first line 8 into the first chamber 5 and the piston 3 is moved to the right.
  • the fluid present in the chamber 6 can flow away to the source 16 via the aperture 9 and the second line 10 and the fifth line 22 with the throttle valve 23 included therein. It will be obvious that in that situation the second closing element 25 must be opened.
  • a force on a roll element 31 of the first closing means 11 by a curve disc 32 shown in Figure 6 on the shut-off valve 12, so that the latter remains against spring pressure in the position shown in Figure 2.
  • the fluid flows back via the second closing means 19, until the pressure set by said second closing means 19 has been reached.
  • the second closing means 19 automatically close the fourth line 14.
  • the third line 13 it is impossible for fluid to flow back to the source 16, because the first non-return valve 15 is included in said line. In this manner it is possible to set the maximum pressure with which the cutter bar 27 bears on the ground.
  • the third closing element 26 is controlled again, so that the second chamber 6 is filled with fluid from the source 16.
  • the first and second closing element 24 and 25 remain closed. It will be obvious that the piston 3 is then allowed to move maximally over a distance X to the left, as the vacuum applied earlier to the first chamber 5 is then removed, and the piston 3 is stopped by the fluid present in the chamber 5. In this manner there is formed a stop created by the fluid for the movement of the cutter bar 27. After the cutter bar 27 with the tractor has turned, it is possible to lower it again by controlling the third closing element 26, in such a manner that the fluid can flow from the second chamber 6 to the source 16. The fluid will then flow until the pressure set by the second closing means 19 has been reached.
  • a third shut-off valve 34 which is preferably controlled manually and which prevents fluid from flowing from the second chamber 6, which would enable the cutter bar 27 to pivot from the transport position 29 into the working position 30.
  • the embodiment shown in Figure 1 functions generally in the same manner as the second embodiment, but in the first embodiment the first closing means are closed automatically and have to be reopened manually for pivoting the machine from the working position 30 or from the intermediate position 33 to the transport position 29.
  • FIG. 3 and Figure 4 show a third embodiment of a control cylinder 1 with a control diagram related thereto, in which parts corresponding to those of the first and the second embodiment are indicated by the same reference numerals.
  • the third embodiment only differs from the second embodiment in that the slide valve 21 is a 6/2-valve which is mechanically controllable against spring pressure and which, in the position shown in Figure 4, interconnects the line 10 and also connects the line 10 with the line 22. Said valve also interconnects the line 8 and connects the line 8 with the line in which the non-return valve 12 is included.
  • the slide valve 21 applied in the third embodiment has relative to the second embodiment the advantage that, if the stop of the piston 3 is only reached after the distance over which the piston 3 has moved in the housing 2 is greater than the distance X, the control cylinder 1 can still be controlled by means of the third closing element 26, which is not possible in the second embodiment in which the control cylinder 1 can exclusively be controlled by means of the second closing element 25.
  • the cutter bar 27 has to be raised temporarily for a short while and has to be brought short thereafter into the working position 30, this can be achieved in the third embodiment by exclusively controlling the third closing means 26. It will be obvious that this offers considerable advantages for the control and that mistakes in controlling the control cylinder 1 are minimized, irrespective of the fact whether the slide valve 21 is activated or deactivated (switched).

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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)
  • Harvester Elements (AREA)
  • Actuator (AREA)
EP01204041A 2000-11-27 2001-10-25 Procédé de contrôle d'un vérin, et machine agricole pour l'application du dit procédé Withdrawn EP1209365A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1016711 2000-11-27
NL1016711A NL1016711C2 (nl) 2000-11-27 2000-11-27 Werkwijze voor het aansturen van een bedieningscilinder, alsmede een landbouwmachine waarin deze werkwijze wordt toegepast.

Publications (2)

Publication Number Publication Date
EP1209365A2 true EP1209365A2 (fr) 2002-05-29
EP1209365A3 EP1209365A3 (fr) 2002-06-05

Family

ID=19772465

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01204041A Withdrawn EP1209365A3 (fr) 2000-11-27 2001-10-25 Procédé de contrôle d'un vérin, et machine agricole pour l'application du dit procédé

Country Status (2)

Country Link
EP (1) EP1209365A3 (fr)
NL (1) NL1016711C2 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1020593C2 (nl) * 2002-05-14 2003-11-17 Lely Entpr Ag Werkwijze voor het aansturen van een bedieningscilinder, een landbouwmachine waarin deze werkwijze wordt toegepast, alsmede inrichting voor het bedienen van een bedieningscilinder.
AT515369A3 (de) * 2014-02-14 2015-12-15 Thomas Dr Löcher Anordnung zur Regelung eines hydraulischen Antriebselements
WO2019011859A3 (fr) * 2017-07-14 2019-02-28 Nordhydraulic Ab Système hydraulique à centre ouvert et vanne
EP2248408B2 (fr) † 2009-04-29 2019-04-03 Kverneland ASA Mécanisme de levage

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB281472A (en) * 1926-11-30 1927-12-08 Brown Brothers & Company Ltd Hydraulic motor control
FR2080242A5 (fr) * 1970-02-27 1971-11-12 Int Harvester Co
DE3337789A1 (de) * 1982-10-25 1984-04-26 Hesston Corp., 67062 Hesston, Kan. Hydraulische schwebeanordnung
WO1987000393A1 (fr) * 1984-02-03 1987-01-29 Rippelton N.V. Appareil pour moissonneuse

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL1020593C2 (nl) * 2002-05-14 2003-11-17 Lely Entpr Ag Werkwijze voor het aansturen van een bedieningscilinder, een landbouwmachine waarin deze werkwijze wordt toegepast, alsmede inrichting voor het bedienen van een bedieningscilinder.
EP2248408B2 (fr) † 2009-04-29 2019-04-03 Kverneland ASA Mécanisme de levage
AT515369A3 (de) * 2014-02-14 2015-12-15 Thomas Dr Löcher Anordnung zur Regelung eines hydraulischen Antriebselements
AT515369B1 (de) * 2014-02-14 2018-03-15 Thomas Dr Loecher Anordnung zur Regelung eines hydraulischen Antriebselements
WO2019011859A3 (fr) * 2017-07-14 2019-02-28 Nordhydraulic Ab Système hydraulique à centre ouvert et vanne
US11168464B2 (en) 2017-07-14 2021-11-09 Nordhydraulic Ab Open center hydraulic system and valve

Also Published As

Publication number Publication date
NL1016711C2 (nl) 2002-05-29
EP1209365A3 (fr) 2002-06-05

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