The disclosure relates to a method for adjusting an orientation angle of an agricultural implement. The method comprising arranging a hitch such that an upper link and at least one lower link is articulated to a support structure of the utility vehicle; and adjusting the orientation angle based on a target length of the upper link, wherein the target length of the upper link is determined as a function of the orientation angle and as a function of a lower link angle.

An inner oil passage (45) is formed inside a slidable spool (22). The slidable spool (22) defines, in its circumferential face, a first opening (46), a second opening (47) and a third opening (48). The first opening (46), the second opening (47) and the third opening (48) are communicated to the inner oil passage (45). When the slidable spool (22) is switched to a floating position (F), the first the first opening (46) is aligned with a first port end portion (25a), the second opening (47) is aligned with a second port end portion (26a), and the third opening (48) is aligned with a fourth port end portion (24a), respectively, and a first cylinder port and a second cylinder port are communicated to a tank port (24) via the inner oil passage (45).

A method is provided for calculating characteristic geometrical or control variables of a three-point hitch for an agricultural tractor in which the hitch includes a lifting strut having a mounting position which is adjustable by means of a lifting arm in one of a plurality of receiving holes formed in a lower link and the hitch is pivotable by the lifting strut. The method includes moving the lower link initially into a horizontal angle position =0 and capturing the corresponding angular position P.sub.x, P.sub.z of the lifting arm and a corresponding angular position of the lifting strut relative to the vertical. The method further includes determining which of the receiving holes satisfies a geometrical constraint condition and determining the mounting position of the lifting strut on the lower link.

A coupling device includes: a first connector that connects to a work vehicle; a second connector that connects to a work device; an actuator that changes a connecting position of at least one of the first connector and the second connector; and a control device that controls the actuator.

Disclosed is a device for hitching and lifting an agricultural tool, including a frame fastened to the agricultural machine, a first arm articulated on the frame with a first tool hitch at one end, at least one first jack, the cylinder or rod being connected to the frame, the other connected to the arm, the jack enabling moving the arm so the extent of the travel of the jack allows the end of the arm bearing the hitch to successively pass through a first (minimum low) position, a second (maximum high) position, and a third (retracted) position, of the supply of the jack, a unit for detecting the position of the end of the arm to deactivate the supply of the jack when the end reaches the second position, and a bypass controller for bypassing the controller of the detection unit, to reactivate the supply of the jack.

An inner oil passage (45) is formed inside a slidable spool (22). The slidable spool (22) defines, in its circumferential face, a first opening (46), a second opening (47) and a third opening (48). The first opening (46), the second opening (47) and the third opening (48) are communicated to the inner oil passage (45). When the slidable spool (22) is switched to a floating position (F), the first the first opening (46) is aligned with a first port end portion (25a), the second opening (47) is aligned with a second port end portion (26a), and the third opening (48) is aligned with a fourth port end portion (24a), respectively, and a first cylinder port and a second cylinder port are communicated to a tank port (24) via the inner oil passage (45).

A method is provided for calculating characteristic geometrical or control variables of a three-point hitch for an agricultural tractor in which the hitch includes a lifting strut having a mounting position which is adjustable by means of a lifting arm in one of a plurality of receiving holes formed in a lower link and the hitch is pivotable by the lifting strut. The method includes moving the lower link initially into a horizontal angle position =0 and capturing the corresponding angular position P.sub.x, P.sub.z of the lifting arm and a corresponding angular position of the lifting strut relative to the vertical. The method further includes determining which of the receiving holes satisfies a geometrical constraint condition and determining the mounting position of the lifting strut on the lower link.

An agricultural work vehicle, such as a tractor, is disclosed. The agricultural work vehicle includes a cab that has a front window and an openable rear window opposite the front window that can be transitioned from a closed position to an open position, an attachment device for connecting a work unit to the agricultural work vehicle, and a camera system with a control unit that is configured to monitor the connecting process. The camera system includes at least one camera which is positioned on the rear window and directed toward the attachment device when the rear window is open. In this way, the at least one camera may provide images to an operator of the agricultural work vehicle during the connecting process.

A working machine includes a machine body, a lifting device to link a working device to the machine body, the lifting device being capable of moving up and down with the working device between a grounding state in which the working device is in contact with a ground and an ungrounding state in which the working device is out of contact with the ground, and an automatic travel controller to cause the machine body to perform automatic travel according to a planned travel route. The automatic travel controller includes a lifting controller to control the lifting device to move up with the working device from the grounding state to the ungrounding state, and cause the machine body to turn or travel rearward after the lifting controller controls the lifting device to move up with the working device from the grounding state to the ungrounding state.

A tractor three-point hitch control system (1) floats a first holding arm and raises a second holding arm to a height of the first holding arm in response to a first holding arm upward force, the second holding arm not experiencing an upward force and the first holding arm being above the first holding arm, (2) floats the first holding arm and raises the second holding arm to the first holding arm height in response to the first holding arm and the second holding arm both experiencing an upward force, and the first holding arm being above the second holding arm, (3) floats the second holding arm and raises the first holding arm to the second holding arm height in response to the first holding arm and the second holding arm both experiencing an upward force, and the second holding arm being above the first holding arm.