A power transmission device includes: a first rotating member rotated by power transmitted from a prime mover; a second rotating member rotating relative to the first rotating member; a first engagement member rotating integrally with the second rotating member at all times; a second engagement member pressed toward the first engagement member; and a moving member rotating integrally with the first rotating member at all times, separated from the first and second engagement members at an initial position, causing the second engagement member to rotate integrally with the first rotating member at a first preparation position where the moving member has moved from the initial position, and causing the second rotating member to rotate integrally with the first rotating member at a first switching position where the moving member has moved from the first preparation position.

A shift control device to be applied to a vehicle provided with an automatic transmission includes a detector and a shift mode control processor. The detector detects that the vehicle has passed through a tollgate through which the vehicle is able to pass without stopping. The shift mode control processor switches a shift mode of the vehicle from a first shift mode to a second shift mode the shift mode of the vehicle upon passing through the tollgate is the first shift mode and a predetermined condition regarding one or both of a speed of the vehicle and an accelerator opening degree of the vehicle is satisfied after the vehicle passes through the tollgate. In the first shift mode, a shift operation is performable by a driver, and in the second shift mode, a shift operation is performable by the automatic transmission.

A shift control device to be applied to a vehicle provided with an automatic transmission includes a detector and a shift mode control processor. The detector detects that the vehicle has passed through a tollgate through which the vehicle is able to pass without stopping. The shift mode control processor switches a shift mode of the vehicle from a first shift mode to a second shift mode the shift mode of the vehicle upon passing through the tollgate is the first shift mode and a predetermined condition regarding one or both of a speed of the vehicle and an accelerator opening degree of the vehicle is satisfied after the vehicle passes through the tollgate. In the first shift mode, a shift operation is performable by a driver, and in the second shift mode, a shift operation is performable by the automatic transmission.

A working vehicle of this invention includes a main speed change structure that includes a continuously variable speed change structure such as an HMT structure and a multi-speed speed change structure capable of switching between a first power transmission state with a first gear ratio and a second power transmission state with a second gear ratio providing a higher speed than the first gear ratio. A control device causes the continuously variable speed change structure to be accelerated to a forward travel side in accordance with an accelerating operation of a speed change operation member in a forward travel direction, and causes the multi-speed speed change structure to be changed from a first power transmission state to a second power transmission state when the rotational speed of the speed change output shaft reaches a switching speed set to exceed a work speed range.

A gearbox (100) includes an input shaft (105), which is connected to a drive source, and a first and a second proportionally controllable shift element (A-F). A method (200) for open-loop control of the gearbox (100) includes: determining (210) an absolute torque demand (330) on the drive source on the basis of a profile controlled by way of an open-loop system (340) and a profile controlled by way of a closed-loop system (345); determining (220) whether the absolute torque demand (330) threatens to exceed a predetermined threshold value (335); and, in response, reducing (225) the portion controlled by way of the closed-loop system (345).

A gearbox (100) includes an input shaft (105), which is connected to a drive source, and a first and a second proportionally controllable shift element (A-F). A method (200) for open-loop control of the gearbox (100) includes: determining (210) an absolute torque demand (330) on the drive source on the basis of a profile controlled by way of an open-loop system (340) and a profile controlled by way of a closed-loop system (345); determining (220) whether the absolute torque demand (330) threatens to exceed a predetermined threshold value (335); and, in response, reducing (225) the portion controlled by way of the closed-loop system (345).

This vehicle control device 10 is provided with: a current gear stage selection unit 13 which selects a current gear stage, which is the gear stage of the vehicle in the present travel state; a travel segment determination unit 15 which determines the next travel segment forwards in the direction of travel of the vehicle V; and a shift control unit 17 which, in the case that the current gear stage selection unit 13 has newly selected a target gear stage lower than the current gear stage during travel of the vehicle V in the current gear stage in the current travel segment, if the next travel segment can be traveled in the current gear stage and the amount the vehicle V will lose speed after traveling the current travel segment is less than or equal to a prescribed threshold value, controls shifting of the gear stage such that downshifting from the current gear stage to the target gear stage is suppressed and the current gear stage is maintained. Even in a state in which downshifting is suppressed, if the state of the vehicle the satisfies a prescribed condition, then the shift control unit 17 controls shifting of the gear stage so as to downshift to the target gear stage without suppression of downshifting.

This vehicle control device 10 is provided with: a current gear stage selection unit 13 which selects a current gear stage, which is the gear stage of the vehicle in the present travel state; a travel segment determination unit 15 which determines the next travel segment forwards in the direction of travel of the vehicle V; and a shift control unit 17 which, in the case that the current gear stage selection unit 13 has newly selected a target gear stage lower than the current gear stage during travel of the vehicle V in the current gear stage in the current travel segment, if the next travel segment can be traveled in the current gear stage and the amount the vehicle V will lose speed after traveling the current travel segment is less than or equal to a prescribed threshold value, controls shifting of the gear stage such that downshifting from the current gear stage to the target gear stage is suppressed and the current gear stage is maintained. Even in a state in which downshifting is suppressed, if the state of the vehicle the satisfies a prescribed condition, then the shift control unit 17 controls shifting of the gear stage so as to downshift to the target gear stage without suppression of downshifting.

A power transmission control device acquires rotation speed information of an idle gear corresponding to a target engagement member and rotation speed information of a sleeve corresponding to an engagement member, sets one rotation speed changeable by a power source as a synchronization side rotation speed, sets the other rotation speed as a target synchronization side rotation speed, allows a differential rotation between the synchronization side rotation speed and the target synchronization side rotation speed to match a predetermined differential rotation by changing the synchronization side rotation speed using the power source after a power transmission releasing state is selected due to a gear changing request, performs an engagement operation, inverts a sign of the predetermined differential rotation, and switches to the power transmission state while allowing the differential rotation to match the predetermined differential rotation of which the sign is inverted.

An electronic control unit suppresses gear shifting more significantly in a second travel mode than in a first travel mode. Accordingly, frequent gear shifting of an automatic transmission in the second travel mode is suppressed, and superior ride quality is obtained. Meanwhile, an amount of a hysteresis in a gear shifting map is smaller in the second travel mode than in the first travel mode. Thus, duration of travel at an optimum gear stage is extended in the second travel mode, and fuel economy is improved. That is, in the second travel mode, drive power responsiveness to an acceleration and deceleration operation as in the first travel mode is unnecessary. Thus, even when gear shifting is suppressed, there is a low possibility that a driver feels a sense of discomfort.