Plough control system for tractor - uses closed loop control to minimise overload of tractor prime mover

    公开(公告)号:DE3017569A1

    公开(公告)日:1981-11-12

    申请号:DE3017569

    申请日:1980-05-08

    Abstract: The engine of a tractor is protected against overload by controlling the position and load of the plough. The system employs an adjustable dead band to ensure that the position of the plough is stable. The tractor plough (13) is positioned by a hydraulic actuator (14) that operates through a linkage (12). High pressure fluid is supplied from a pump in association with a 3/3 directional valve (15). An electronic controller (46) responds to a reference load input (28) and a number of feedback signals. The feedback signals are provided by a plough position sensor (18), and injection pump rate (24) indicating torque. Other inputs are provided for reference torque (28), reference speed (29)and reference position (22).

    22.
    发明专利
    未知

    公开(公告)号:RO75024A

    公开(公告)日:1980-10-30

    申请号:RO9239777

    申请日:1977-12-08

    Abstract: In a servo system for manipulating a displaceble member in response to movement of a control through corresponding changes of position, which operates by comparing an electrical signal representative of the position of the control with an electrical signal representative of the position of the displaceable member to provide error signals which can drive the displaceable member in either of two opposite directions, a safety interlock circuit is provided which detects the presence of an error signal in either direction immediately after the application of operating voltage or immediately after the switching of the machinery into a different mode of operation and locks the displaceable member in position if an error signal initially appears until the error signal is cancelled by bringing the manual control into a position corresponding with that of the displaceable member. Unexpected sudden movements that may endanger personnel are thereby prevented. The invention is illustrated with reference to mobile agricultural machinery.

    23.
    发明专利
    未知

    公开(公告)号:DE2655906A1

    公开(公告)日:1978-06-22

    申请号:DE2655906

    申请日:1976-12-09

    Abstract: In a servo system for manipulating a displaceble member in response to movement of a control through corresponding changes of position, which operates by comparing an electrical signal representative of the position of the control with an electrical signal representative of the position of the displaceable member to provide error signals which can drive the displaceable member in either of two opposite directions, a safety interlock circuit is provided which detects the presence of an error signal in either direction immediately after the application of operating voltage or immediately after the switching of the machinery into a different mode of operation and locks the displaceable member in position if an error signal initially appears until the error signal is cancelled by bringing the manual control into a position corresponding with that of the displaceable member. Unexpected sudden movements that may endanger personnel are thereby prevented. The invention is illustrated with reference to mobile agricultural machinery.

    24.
    发明专利
    未知

    公开(公告)号:DE2240607A1

    公开(公告)日:1974-02-28

    申请号:DE2240607

    申请日:1972-08-18

    Abstract: The system includes a hydraulic user device and a source of hydraulic fluid. A hydraulic arrangement connects the source of fluid to the user device and provides a path for the flow of fluid from the source to the user device, and includes a control member positioned in such path and mounted for movement between a plurality of positions in different ones of which the control member differently affects the flow of fluid from the source to the user device, including a neutral position in which the control member blocks the flow of fluid from the source to the user device. An electrohydraulic moving arrangement is operative when electrically energized for moving the control member by applying hydraulic force thereto. A restoring arrangement is operative for applying to the control member a restoring force tending to move the control member to said neutral position when the electrohydraulic moving arrangement is electrically unenergized. An electrical control arrangement controls the electrohydraulic moving arrangement and includes a source of electrical power having two terminals, connectors connecting the source of electrical power to the electrohydraulic moving arrangement for furnishing electrical energy to the latter, a remote control arrangement and an electrical control cable having a first cable end connected to the electrohydraulic moving unit and a second cable end connected to the remote control arrangement, the control cable comprising a first conductor having at the first cable end a first end connected to one terminal of the source of electrical power and having a second end at the second cable end, a second conductor extending along the length of the cable and having a first end at the first cable end and a second end at the second cable end. A fail-safe unit prevents electrical energization of the electrohydraulic moving arrangement when a short-circuit develops between the first and second conductors, to prevent the application by the electrohydraulic moving arrangement of hydraulic force to the control member and to thereby cause the control member to be returned to the neutral position by the restoring means.

    27.
    发明专利
    未知

    公开(公告)号:DE3522818C2

    公开(公告)日:1994-07-21

    申请号:DE3522818

    申请日:1985-06-26

    Abstract: In a device for controlling a slip and a traction force of an implement coupled to a tractor by a hoisting unit, a slip contol system is combined with a traction force control system. The control device includes a drive speed sensor connected to the tractor and an acceleration sensor positioned on the tractor. A measured acceleration value is compared in a comparator circuit with an adjusted output signal of the drive speed sensor, and an actual slip value is determined by integration from an acceleration difference signal. The actual slip value is used for adjusting a control value generated in the traction force control system to control a position of the hoisting unit.

    28.
    发明专利
    未知

    公开(公告)号:IT1140103B

    公开(公告)日:1986-09-24

    申请号:IT2551981

    申请日:1981-12-11

    Abstract: To prevent a tractor pulling a plow (P) from digging itself in, if the plow position, with respect to soil or tractor level, is controlled by an automatic control system which causes the plow to be lowered if the pulling force of the tractor decreases, slip of the drive wheels of the tractor is sensed and an overriding command signal given to the plow positioning system (S) tending to raise the plow, or, alternatively, a visual indication is given to the operator that the plough should be raised manually; the slip condition is sensed by differentiating a signal representative of plow position, with respect to time, and comparing the so differentiated plow positioning signal (or, in other words, plow dropping speed signal) with a reference which, preferably, includes such factors as tractor engine speed, tractor and/or implement weight, ground wheel adhesion, tractor gearing, and the like.

    29.
    发明专利
    未知

    公开(公告)号:FR2495886B1

    公开(公告)日:1985-12-13

    申请号:FR8117805

    申请日:1981-09-21

    Abstract: To prevent a tractor pulling a plow (P) from digging itself in, if the plow position, with respect to soil or tractor level, is controlled by an automatic control system which causes the plow to be lowered if the pulling force of the tractor decreases, slip of the drive wheels of the tractor is sensed and an overriding command signal given to the plow positioning system (S) tending to raise the plow, or, alternatively, a visual indication is given to the operator that the plough should be raised manually; the slip condition is sensed by differentiating a signal representative of plow position, with respect to time, and comparing the so differentiated plow positioning signal (or, in other words, plow dropping speed signal) with a reference which, preferably, includes such factors as tractor engine speed, tractor and/or implement weight, ground wheel adhesion, tractor gearing, and the like.

    DISPOZITIV PENTRU REGLAREA FARA REACTIE A COEFICIENTULUI DE MIXARE LA MECANISMELE DE RIDICARE ALE MASINILOR AGRICOLE

    公开(公告)号:RO84422B

    公开(公告)日:1984-08-30

    申请号:RO10820582

    申请日:1982-07-20

    Inventor: ARNOLD WINFRIED

    Abstract: Inventia se refera la un dispozitiv pentru reglarea mecanismelor de ridicare ale masinilor agricole, la care reglarea sa poate fi facuta atît în functie de pozitie, cît si în functie de forta. Valoarea fortei este etalonata în functie de semnalul de indicare a pozitiei la anumite momente, astfel încît o modificare a raportului de mixare în reglorul de mixare sa nu duca la o modificare a pozitiei. Etalonarea se face prin intermediul unui regulator PI si a unui circuit de memorie, într-un amplificator diferential, efectuîndu-se scaderea semnalului traductorului de indicare a fortei a unui semnal suplimentar înmagazinat, astfel încît, în starea etalonata, semnalul de indicare a fortei este egal cu cel de indicare a pozitiei. în aceasta situatie, o noua reglare a reglorului de mixare nu provoaca o modificare a pozitiei dispozitivului de ridicare. Datorita unuor dispozitive suplimentare, se obtine ca aceasta etalonare sa poata fi mereu reînnoita, în functie de una sau mai multe marimi. La o actiune a reglorului valorii prescrise a pozitiei, se slabeset semnalul de mixare, astfel încît este atinsa în scurt timp pozitia dorita.

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