A drive device includes: an actuator rotating, around a rotation axis, a shift drum having a lead groove formed on an outer peripheral surface; and an angle correction unit correcting a detection value of a rotation angle sensor that detects a rotation angle of the shift drum. The angle correction unit calculates the rotation angle of the shift drum at a reference position as a learning angle based on a correspondence between a displacement amount of a first engaging portion and a change amount of the rotation angle of the shift drum per a predetermined time of rotation of the shift drum at a predetermined speed. Then, the angle correction unit corrects the detection value of the rotation angle sensor based on an amount of deviation between the learning angle and a design angle.

A drive device includes: an actuator rotating, around a rotation axis, a shift drum having a lead groove formed on an outer peripheral surface; and an angle correction unit correcting a detection value of a rotation angle sensor that detects a rotation angle of the shift drum. The angle correction unit calculates the rotation angle of the shift drum at a reference position as a learning angle based on a correspondence between a displacement amount of a first engaging portion and a change amount of the rotation angle of the shift drum per a predetermined time of rotation of the shift drum at a predetermined speed. Then, the angle correction unit corrects the detection value of the rotation angle sensor based on an amount of deviation between the learning angle and a design angle.

A control device includes: an engagement mechanism having a first engagement element and a second engagement element; and an actuator that generates a thrust that brings the first engagement element and the second engagement element close to each other when the engagement mechanism is engaged. The control device performs engagement with the thrust of the actuator when a differential rotation speed of the engagement mechanism is less than a predetermined value. In the control device, a parameter indicating an operating state of the actuator is detected, a target differential rotation speed is calculated in accordance with a value of the detected parameter, and the differential rotation speed is controlled to the calculated target differential rotation speed.

A control device includes: an engagement mechanism having a first engagement element and a second engagement element; and an actuator that generates a thrust that brings the first engagement element and the second engagement element close to each other when the engagement mechanism is engaged. The control device performs engagement with the thrust of the actuator when a differential rotation speed of the engagement mechanism is less than a predetermined value. In the control device, a parameter indicating an operating state of the actuator is detected, a target differential rotation speed is calculated in accordance with a value of the detected parameter, and the differential rotation speed is controlled to the calculated target differential rotation speed.

A dog clutch engagement method of an electric four-wheel drive vehicle includes steps of: when dog clutch engagement is requested during driving, determining a target synchronization speed of the input gear to be a sum of an estimated speed and an offset speed of the output gear; operating a drive unit so that an input gear follows the target synchronization speed; when an actual speed of the input gear reaches the target synchronization speed, moving a sleeve to a meeting position at which the sleeve is in contact with the input gear; and when the actual speed of the input gear is synchronized with an actual speed of the output gear, transporting the sleeve to an engagement position at which the input gear and the output gear are coupled.

An agricultural machine configured to be operated by an operator and including a drive mechanism having a drive shaft and a gear assembly for driving an agricultural implement. The agricultural machine includes a slip clutch that has an outer sleeve operatively coupled to the gear assembly, an inner sleeve positioned within the outer sleeve and coupled to and rotatable with the drive shaft, a plurality of torque-transfer members positioned between the outer sleeve and the inner sleeve and configured to selectively couple the inner sleeve to the outer sleeve, and a position sensor in communication with one of the plurality of torque-transfer members and configured to output a signal in response to radial displacement of the one torque-transfer member being detected. The agricultural machine includes a control unit in communication with the position sensor and configured to alter an operating parameter of the machine in response to receiving the signal.

An agricultural machine configured to be operated by an operator and including a drive mechanism having a drive shaft and a gear assembly for driving an agricultural implement. The agricultural machine includes a slip clutch that has an outer sleeve operatively coupled to the gear assembly, an inner sleeve positioned within the outer sleeve and coupled to and rotatable with the drive shaft, a plurality of torque-transfer members positioned between the outer sleeve and the inner sleeve and configured to selectively couple the inner sleeve to the outer sleeve, and a position sensor in communication with one of the plurality of torque-transfer members and configured to output a signal in response to radial displacement of the one torque-transfer member being detected. The agricultural machine includes a control unit in communication with the position sensor and configured to alter an operating parameter of the machine in response to receiving the signal.

A dog clutch engagement method of an electric four-wheel drive vehicle includes steps of: when dog clutch engagement is requested during driving, determining a target synchronization speed of the input gear to be a sum of an estimated speed and an offset speed of the output gear; operating a drive unit so that an input gear follows the target synchronization speed; when an actual speed of the input gear reaches the target synchronization speed, moving a sleeve to a meeting position at which the sleeve is in contact with the input gear; and when the actual speed of the input gear is synchronized with an actual speed of the output gear, transporting the sleeve to an engagement position at which the input gear and the output gear are coupled.

A dog clutch engagement method of an electric four-wheel drive vehicle includes steps of: when dog clutch engagement is requested during driving, determining a target synchronization speed of the input gear to be a sum of an estimated speed and an offset speed of the output gear; operating a drive unit so that an input gear follows the target synchronization speed; when an actual speed of the input gear reaches the target synchronization speed, moving a sleeve to a meeting position at which the sleeve is in contact with the input gear; and when the actual speed of the input gear is synchronized with an actual speed of the output gear, transporting the sleeve to an engagement position at which the input gear and the output gear are coupled.

A control device includes: an engagement mechanism having a first engagement element and a second engagement element; and an actuator that generates a thrust that brings the first engagement element and the second engagement element close to each other when the engagement mechanism is engaged. The control device performs engagement with the thrust of the actuator when a differential rotation speed of the engagement mechanism is less than a predetermined value. In the control device, a parameter indicating an operating state of the actuator is detected, a target differential rotation speed is calculated in accordance with a value of the detected parameter, and the differential rotation speed is controlled to the calculated target differential rotation speed.