WO2013026661A1 - Agricultural tractor linkage control system - Google Patents

Agricultural tractor linkage control system Download PDF

Info

Publication number
WO2013026661A1
WO2013026661A1 PCT/EP2012/064935 EP2012064935W WO2013026661A1 WO 2013026661 A1 WO2013026661 A1 WO 2013026661A1 EP 2012064935 W EP2012064935 W EP 2012064935W WO 2013026661 A1 WO2013026661 A1 WO 2013026661A1
Authority
WO
WIPO (PCT)
Prior art keywords
implement
pitch
ecu
tractor
control system
Prior art date
Application number
PCT/EP2012/064935
Other languages
French (fr)
Inventor
Jacques Pirotais
Original Assignee
Agco Sa
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 Agco Sa filed Critical Agco Sa
Publication of WO2013026661A1 publication Critical patent/WO2013026661A1/en

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Classifications

    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01B—SOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL
    • A01B59/00—Devices specially adapted for connection between animals or tractors and agricultural machines or implements
    • A01B59/002—Details, component parts
    • A01B59/004—Length-adjustable links
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01B—SOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL
    • A01B63/00—Lifting or adjusting devices or arrangements for agricultural machines or implements
    • A01B63/02—Lifting or adjusting devices or arrangements for agricultural machines or implements for implements mounted on tractors
    • A01B63/10—Lifting or adjusting devices or arrangements for agricultural machines or implements for implements mounted on tractors operated by hydraulic or pneumatic means
    • A01B63/111—Lifting or adjusting devices or arrangements for agricultural machines or implements for implements mounted on tractors operated by hydraulic or pneumatic means regulating working depth of implements
    • A01B63/114—Lifting or adjusting devices or arrangements for agricultural machines or implements for implements mounted on tractors operated by hydraulic or pneumatic means regulating working depth of implements to achieve a constant working depth

Definitions

  • the invention relates to agricultural tractors and the control of three point linkage to which an implement can be attached.
  • a three point linkage comprises a pair of lift arms and a centre top link which are each connected between respective mounting points on the implement and the tractor.
  • Raising and lowering of an attached implement is facilitated by hydraulically- actuated lift cylinders connected to the lift arms which are controlled by the application of various hydraulics signals from a linkage control system.
  • the top link is connected at each end in a passive manner and serves to provide triangulation for the linkage.
  • the length of a top link has been adjusted by a mechanical screw thread.
  • Today more modern top links include a hydraulic cylinder which allows adjustment of the length remotely using the application of appropriate hydraulic inputs.
  • the length of the top link is adjustable to allow setting of the pitch of the attached implement. Moreover, different implements have different linkage geometry thereby demanding a different length of top link.
  • a driver When reaching a field a driver is often required to adjust the length of the top link to set the pitch of the attached implement. For example, in the case of a chisel- based cultivation tool the pitch is set so that the front ground engagement elements engage the ground with a similar depth to the rear ground engaging elements.
  • a linkage control system on an agricultural tractor comprising a three-point linkage arrangement for attaching an implement and having two lift arms and an automatically adjustable top link, the system further comprising an electronic control unit (ECU) that controls the
  • the ECU having an input for receiving a signal representative of implement pitch from an angle sensor disposed on an attached implement, wherein the ECU, in response to an activation command received from a driver, adjusts the length of the top link to achieve a target implement pitch.
  • the desired (or target) pitch can be preset and the driver can simply level the implement at the touch of a button. This alleviates the driver with the need to leave the cab to level or set the implement pitch.
  • the target implement pitch is preset and stored by the ECU.
  • the stored target pitch will be normally associated with levelling of the implement (to give a uniform tillage job for example).
  • the stored target pitch may correspond to an angle other than horizontal and may, for example, be associated with a particular mode of operation for a given implement.
  • a rotary hay tool (a Haybob (registered trade mark) for example) may be operable in a rowing mode or a shaking mode, each of which requiring a different target implement pitch.
  • Activation of the command is preferably carried out on flat ground when the tractor is level.
  • the tractor may also include a tractor angle sensor disposed on the tractor and in communication with the ECU, the tractor angle sensor generating a signal that is representative of the tractor's pitch.
  • the target implement pitch may be augmented or adjusted by the sensed pitch of the tractor.
  • this caters for adjustment of the top link when the tractor/implement combination is parked on slope.
  • the respective tractor and implement angle sensors may be similar in type, thereby generating comparable signals.
  • the length of the top link may be adjusted to minimise the difference between the sensed tractor pitch and the sensed implement pitch.
  • the automatically adjustable top link may be hydraulically or electrically actuated to adjust its length.
  • FIG. 1 is a schematic side view of a tractor and Implement embodying a linkage control system in the accordance the invention
  • Figure 2 is a schematic representation of the linkage control system of Figure 1 ;
  • FIG. 3 is a flow chart illustrating the process carried out by the ECU in a linkage control system in accordance with the invention.
  • an agricultural tractor 10 has mounted thereto an implement in the form of a cultivator tool 12. It will of course be appreciated that the invention may apply to any type of mounted implement from the non-exhaustive list of hay tools, cultivation/tillage tools, etc.
  • the cultivator 12 is mounted to the tractor 10 by a three point linkage of a known construction which includes a pair of lower lift arms 14 and a top link 16. It will be appreciated that only one lower lift arm 14 is shown. As is known, the length of top link 16 is adjustable to change the pitch of the cultivator so that the ground engaging tines 18 interact with the soil at a uniform depth.
  • a linkage control system 20 comprises an ECU 22 which controls the length of hydraulically-actuated top link 16.
  • a hydraulic controller 24 is in communication with ECU 22 in a wired or wireless manner. Signals sent by ECU 22 to hydraulic controller 24 control valves (not shown) included in the latter which direct hydraulic pressures to either end of hydraulic top link 16 via lines A and B.
  • Hydraulic top link 16 includes a hydraulic cylinder having a piston separating two chambers (not shown), the volumes of which are controlled by the application of said hydraulic signals.
  • a position sensor (not shown) embedded in the hydraulic top link 16 generates a position signal which is communicated back to the ECU 22 to enable a closed-loop control thereof.
  • a first angle sensor 26 is positioned on the implement 12 and is in communication (either wired or wirelessly) with ECU 22. Furthermore, a second angle sensor 28 is disposed on the tractor 10 and is in communication with ECU 22. Both angle sensors 26, 28 generate a signal that is representative of the current pitch of the implement 12 or tractor 10 respectively, said signals being communicated to ECU 22.
  • the linkage control system 20 also includes a user interface device (not shown) which may be a press button, a button on a touch-sensitive screen or otherwise.
  • the device is in communication with ECU 22.
  • the ECU 22 has stored therein a target pitch for the implement which may have been inputted manually by a driver or stored from a previous setting. Moreover, the target pitch may be associated with a specific mode for a particular tool which can operate in a plurality of different modes.
  • the ECU then commands adjustment of the top link 16 until the sensed implement pitch is equal to, or substantially equal to, the stored target pitch.
  • the length of the top link 16 is then held in this position unless adjusted by another automated function or manually by the operator.

Abstract

A linkage control system (20) for use on an agricultural tractor (10) is provided. The system comprises a three-point linkage arrangement for attaching an implement (12). The linkage has two lift arms (14) and an automatically adjustable top link (16). The system further comprises an electronic control unit (ECU) that controls the length of the top link. The ECU has an input for receiving a signal representative of implement pitch from an angle sensor (26) disposed on the attached implement. The ECU, in response to an activation command received from a driver, adjusts the length of the top link to achieve a target implement pitch.

Description

DESCRIPTION
AGRICULTURAL TRACTOR LINKAGE CONTROL SYSTEM
[01] The invention relates to agricultural tractors and the control of three point linkage to which an implement can be attached.
[02] Three point linkages have been used on agricultural tractors for many decades to mount various implements thereto. A three point linkage comprises a pair of lift arms and a centre top link which are each connected between respective mounting points on the implement and the tractor.
[03] Raising and lowering of an attached implement is facilitated by hydraulically- actuated lift cylinders connected to the lift arms which are controlled by the application of various hydraulics signals from a linkage control system. The top link is connected at each end in a passive manner and serves to provide triangulation for the linkage. Traditionally, the length of a top link has been adjusted by a mechanical screw thread. Today more modern top links include a hydraulic cylinder which allows adjustment of the length remotely using the application of appropriate hydraulic inputs.
[04] The length of the top link is adjustable to allow setting of the pitch of the attached implement. Moreover, different implements have different linkage geometry thereby demanding a different length of top link.
[05] When reaching a field a driver is often required to adjust the length of the top link to set the pitch of the attached implement. For example, in the case of a chisel- based cultivation tool the pitch is set so that the front ground engagement elements engage the ground with a similar depth to the rear ground engaging elements.
[06] It is an object of the invention to provide a linkage control system which is more convenient to use for the driver.
[07] In accordance with the invention there is provided a linkage control system on an agricultural tractor, the system comprising a three-point linkage arrangement for attaching an implement and having two lift arms and an automatically adjustable top link, the system further comprising an electronic control unit (ECU) that controls the
I length of the top link, the ECU having an input for receiving a signal representative of implement pitch from an angle sensor disposed on an attached implement, wherein the ECU, in response to an activation command received from a driver, adjusts the length of the top link to achieve a target implement pitch.
[08] By providing an angle sensor on the implement and communicating the sensed pitch to the ECU, the desired (or target) pitch can be preset and the driver can simply level the implement at the touch of a button. This alleviates the driver with the need to leave the cab to level or set the implement pitch.
[09] Preferably, the target implement pitch is preset and stored by the ECU. Advantageously, this allows the system to recall the target pitch once the attached implement is identified either automatically or by data entry from the operator. The stored target pitch will be normally associated with levelling of the implement (to give a uniform tillage job for example). However, it is envisaged that the stored target pitch may correspond to an angle other than horizontal and may, for example, be associated with a particular mode of operation for a given implement. For example, a rotary hay tool (a Haybob (registered trade mark) for example) may be operable in a rowing mode or a shaking mode, each of which requiring a different target implement pitch.
[10] Activation of the command is preferably carried out on flat ground when the tractor is level. However, in an improved embodiment, the tractor may also include a tractor angle sensor disposed on the tractor and in communication with the ECU, the tractor angle sensor generating a signal that is representative of the tractor's pitch. In this case the target implement pitch may be augmented or adjusted by the sensed pitch of the tractor. Advantageously, this caters for adjustment of the top link when the tractor/implement combination is parked on slope.
[11] The respective tractor and implement angle sensors may be similar in type, thereby generating comparable signals. In this case, the length of the top link may be adjusted to minimise the difference between the sensed tractor pitch and the sensed implement pitch.
[12] The automatically adjustable top link may be hydraulically or electrically actuated to adjust its length. [13] Advantages of the invention will become apparent from reading the following description of a specific embodiment with reference to the appended drawings in which:-
[14] Figure 1 is a schematic side view of a tractor and Implement embodying a linkage control system in the accordance the invention;
[15] Figure 2 is a schematic representation of the linkage control system of Figure 1 ; and,
[16] Figure 3 is a flow chart illustrating the process carried out by the ECU in a linkage control system in accordance with the invention.
[17] In the following description of the example embodiment relative terms will be used based upon the normal forward direction of the tractor. For example the term 'pitch' should be understood to mean the degree of freedom around a transverse, or horizontal side-to-side, axis.
[18] With reference to Figures 1 and 2 an agricultural tractor 10 has mounted thereto an implement in the form of a cultivator tool 12. It will of course be appreciated that the invention may apply to any type of mounted implement from the non-exhaustive list of hay tools, cultivation/tillage tools, etc.
[19] The cultivator 12 is mounted to the tractor 10 by a three point linkage of a known construction which includes a pair of lower lift arms 14 and a top link 16. It will be appreciated that only one lower lift arm 14 is shown. As is known, the length of top link 16 is adjustable to change the pitch of the cultivator so that the ground engaging tines 18 interact with the soil at a uniform depth.
[20] With reference to Figure 2, a linkage control system 20 comprises an ECU 22 which controls the length of hydraulically-actuated top link 16. To explain further, a hydraulic controller 24 is in communication with ECU 22 in a wired or wireless manner. Signals sent by ECU 22 to hydraulic controller 24 control valves (not shown) included in the latter which direct hydraulic pressures to either end of hydraulic top link 16 via lines A and B. Hydraulic top link 16 includes a hydraulic cylinder having a piston separating two chambers (not shown), the volumes of which are controlled by the application of said hydraulic signals. A position sensor (not shown) embedded in the hydraulic top link 16 generates a position signal which is communicated back to the ECU 22 to enable a closed-loop control thereof.
[21] A first angle sensor 26 is positioned on the implement 12 and is in communication (either wired or wirelessly) with ECU 22. Furthermore, a second angle sensor 28 is disposed on the tractor 10 and is in communication with ECU 22. Both angle sensors 26, 28 generate a signal that is representative of the current pitch of the implement 12 or tractor 10 respectively, said signals being communicated to ECU 22.
[22] The linkage control system 20 also includes a user interface device (not shown) which may be a press button, a button on a touch-sensitive screen or otherwise. The device is in communication with ECU 22.
[23] The ECU 22 has stored therein a target pitch for the implement which may have been inputted manually by a driver or stored from a previous setting. Moreover, the target pitch may be associated with a specific mode for a particular tool which can operate in a plurality of different modes.
[24] The function of the linkage control system 20 in accordance with the invention will be described with reference to Figure 3. In a first step the driver activates the auto-level command by pressing the button mentioned above.
[25] The ECU then commands adjustment of the top link 16 until the sensed implement pitch is equal to, or substantially equal to, the stored target pitch. The length of the top link 16 is then held in this position unless adjusted by another automated function or manually by the operator.

Claims

1. A linkage control system on an agricultural tractor, the system comprising a three-point linkage arrangement for attaching an implement and having two lift arms and an automatically adjustable top link, the system further comprising an electronic control unit (ECU) that controls the length of the top link, the ECU having an input for receiving a signal representative of implement pitch from an angle sensor disposed on an attached implement, wherein the ECU, in response to an activation command received from a driver, adjusts the length of the top link to achieve a target implement pitch.
2. A control system according to Claim 1 , further comprising a tractor angle sensor disposed on the tractor and in communication with the ECU, the tractor angle sensor generating a signal that is representative of the tractor's pitch, wherein the target implement pitch is determined based upon the sensed pitch of the tractor.
3. A control system according to Claim 2, wherein the ECU adjusts the length of the top link to minimise the difference between the sensed tractor pitch and the sensed implement pitch.
4. A control system according to any preceding claim, wherein the automatically adjustable top link is hydraulically actuated.
5. A control system according to any one of Claims 1 , 2 or 3, wherein the automatically adjustable top link is actuated by an electric motor.
6. A control system according to any preceding claim, wherein an implement is attached to the tractor and the system further comprises the angle sensor disposed on the attached implement.
7. A control system according to any preceding claim, further comprising a user interface device in communication with the ECU, wherein the activation command is received via the user interface device.
PCT/EP2012/064935 2011-08-23 2012-07-31 Agricultural tractor linkage control system WO2013026661A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1114454.0 2011-08-23
GBGB1114454.0A GB201114454D0 (en) 2011-08-23 2011-08-23 Agricultural tractor linkage control system

Publications (1)

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WO2013026661A1 true WO2013026661A1 (en) 2013-02-28

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WO (1) WO2013026661A1 (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9516796B2 (en) 2013-11-13 2016-12-13 Cnh Industrial Canada, Ltd. Agricultural tillage implement wheel control
WO2017007412A1 (en) * 2015-07-07 2017-01-12 Väderstad Holding Ab Agricultural implement and method of controlling an agricultural implement
US9661798B2 (en) 2013-11-13 2017-05-30 Cnh Industrial America Llc Agricultural tillage implement wheel control
CN107182313A (en) * 2017-07-07 2017-09-22 中国农业大学 Self-excited vibration subsoiler and tilling depth investigating method
US9801323B2 (en) 2013-11-13 2017-10-31 Cnh Industrial America Llc Rocker link lift system
US9844184B2 (en) 2015-03-17 2017-12-19 Agco Corporation Header position sensing system for an agricultural harvester
EP3295779A1 (en) * 2016-09-20 2018-03-21 Deere & Company Upper guide for a three point power lift of an agricultural tractor
US10251328B2 (en) 2016-11-18 2019-04-09 Cnh Industrial America Llc Electronic sensor assembly for monitoring smoothing tools of a harrow
US10314223B2 (en) 2014-06-13 2019-06-11 Väderstad Holding Ab Agricultural implement having frame sections moveable relative each other
US10420271B2 (en) 2014-11-10 2019-09-24 Cnh Industrial America Llc Fully adjustable lift system
EP3289847B1 (en) 2016-09-01 2020-01-01 Deere & Company Arrangement for influencing the position of an agricultural attachment
US10561052B2 (en) 2017-04-25 2020-02-18 Cnh Industrial Canada, Ltd. Automatic fore/aft leveling trim function in a towable tillage implement
EP3944751A1 (en) 2020-07-29 2022-02-02 CLAAS Saulgau GmbH Control system for an agricultural vehicle set comprising a tractor and a mower, mower and vehicle set

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109328511A (en) * 2018-11-22 2019-02-15 上海宏英智能科技有限公司 A kind of tractor pendent eT self-level(l)ing device and its collecting method

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GB2123670A (en) * 1982-07-16 1984-02-08 Kubota Ltd Controlling implements on three-point linkages
DE10140383A1 (en) * 2001-08-23 2003-03-13 Rau Serta Hydraulik Gmbh Control or regulation of position of auxiliary tool fitted to tractor involves operating tool mounting device if tractor inclination changes to maintain tool inclination relative to horizontal
FR2840764A1 (en) * 2002-06-18 2003-12-19 Hubert Defrancq Lifting system for agricultural tool coupled to tractor comprises two lower arms articulated to shaft linked to tractor for attaching tool low lateral points and upper linking element for third point, arms controlled by lifting actuator
EP2457429A1 (en) * 2010-11-30 2012-05-30 Agrotronix Agricultural machine with automatic stability correction

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2123670A (en) * 1982-07-16 1984-02-08 Kubota Ltd Controlling implements on three-point linkages
DE10140383A1 (en) * 2001-08-23 2003-03-13 Rau Serta Hydraulik Gmbh Control or regulation of position of auxiliary tool fitted to tractor involves operating tool mounting device if tractor inclination changes to maintain tool inclination relative to horizontal
FR2840764A1 (en) * 2002-06-18 2003-12-19 Hubert Defrancq Lifting system for agricultural tool coupled to tractor comprises two lower arms articulated to shaft linked to tractor for attaching tool low lateral points and upper linking element for third point, arms controlled by lifting actuator
EP2457429A1 (en) * 2010-11-30 2012-05-30 Agrotronix Agricultural machine with automatic stability correction

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9661798B2 (en) 2013-11-13 2017-05-30 Cnh Industrial America Llc Agricultural tillage implement wheel control
US9801323B2 (en) 2013-11-13 2017-10-31 Cnh Industrial America Llc Rocker link lift system
US9999172B2 (en) 2013-11-13 2018-06-19 Cnh Industrial Canada, Ltd. Agricultural tillage implement wheel control
US9516796B2 (en) 2013-11-13 2016-12-13 Cnh Industrial Canada, Ltd. Agricultural tillage implement wheel control
US10314223B2 (en) 2014-06-13 2019-06-11 Väderstad Holding Ab Agricultural implement having frame sections moveable relative each other
US10420271B2 (en) 2014-11-10 2019-09-24 Cnh Industrial America Llc Fully adjustable lift system
US9844184B2 (en) 2015-03-17 2017-12-19 Agco Corporation Header position sensing system for an agricultural harvester
US10687453B2 (en) 2015-07-07 2020-06-23 Väderstad Holding Ab Agricultural implement and method of controlling an agricultural implement
WO2017007412A1 (en) * 2015-07-07 2017-01-12 Väderstad Holding Ab Agricultural implement and method of controlling an agricultural implement
EP3289847B2 (en) † 2016-09-01 2022-09-28 Deere & Company Arrangement for influencing the position of an agricultural attachment
EP3289847B1 (en) 2016-09-01 2020-01-01 Deere & Company Arrangement for influencing the position of an agricultural attachment
EP3295779A1 (en) * 2016-09-20 2018-03-21 Deere & Company Upper guide for a three point power lift of an agricultural tractor
US10251328B2 (en) 2016-11-18 2019-04-09 Cnh Industrial America Llc Electronic sensor assembly for monitoring smoothing tools of a harrow
US10561052B2 (en) 2017-04-25 2020-02-18 Cnh Industrial Canada, Ltd. Automatic fore/aft leveling trim function in a towable tillage implement
US10973162B2 (en) 2017-04-25 2021-04-13 Cnh Industrial Canada, Ltd. Method for adjusting the fore/aft trim of a towed implement frame
CN107182313A (en) * 2017-07-07 2017-09-22 中国农业大学 Self-excited vibration subsoiler and tilling depth investigating method
EP3944751A1 (en) 2020-07-29 2022-02-02 CLAAS Saulgau GmbH Control system for an agricultural vehicle set comprising a tractor and a mower, mower and vehicle set
DE102020119957A1 (en) 2020-07-29 2022-02-03 Claas Saulgau Gmbh Control system for an agricultural tractor-trailer combination of a towing vehicle and a mower, mower and trailer

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