A shift control apparatus (80) for a vehicle (10; 100) provided with a drive power source (39; MG), and a step-variable transmission portion (20; 110) including a plurality of hydraulically operated coupling devices (CB), the shift control apparatus controlling the step-variable transmission portion to implement a shifting action with an engaging action of the engaging-side coupling device and a releasing action of the releasing-side coupling device, and including a shift control portion (82) to control a shift-down action of the step-variable transmission portion in a predetermined mode of hydraulic control of the engaging-side and releasing-side coupling devices, wherein the shift control portion controls the engaging-side and releasing-side coupling devices in a non-vehicle-driving control mode during the shift-down action of the step-variable transmission portion in a non-driving state of the vehicle, the shift control portion switching the mode of hydraulic control from the non-vehicle-driving control mode to a vehicle-driving control mode where the vehicle is switched from the non-driving state to a driving state within a predetermined length of time after a moment of initiation of the shift-down action, and maintaining the non-vehicle-driving control mode where the vehicle is switched to the driving state after the predetermined length of time has passed, while limiting a torque of the drive power source during the shift-down action to a predetermined value in the non-vehicle-driving control mode.

A transmission system for a vehicle, comprising: an input configured to couple to a prime mover of the vehicle; a first gear ratio; a second gear ratio; a first dynamic controllable clutch operable in an engaged state, a disengaged state, and a one-way clutch state; a second dynamic controllable clutch operable in the engaged state, the disengaged state, and the one-way clutch state; an output; and a controller comprising instructions stored in non-transitory memory that are executable by the controller to: adjust a state of the first DCC and the second DCC to selectively engage the first gear ratio and the second gear ratio for providing torque transfer from the input to the output of the transmission system.

A shift position switching device for shifting gears in association with a shift position. The device includes a shift mechanism switching between shift positions using a drive power of a motor, an encoder outputting pulse signals in sync with a rotation of the motor, and a controller rotating the motor to a target rotation position corresponding to an intended gear. The controller rotates the motor toward a dead-end on a first shift position side of the shift mechanism while observing a motor rotation speed or an acceleration of rotation of the motor based on the outputted pulse signals of the encoder. Also, the controller learns, as a reference position on the first shift position side, a first rotation position of the motor.

A shift control apparatus (80) for a vehicle (10; 100) provided with a drive power source (39; MG), and a step-variable transmission portion (20; 110) including a plurality of hydraulically operated coupling devices (CB), the shift control apparatus controlling the step-variable transmission portion to implement a shifting action with an engaging action of the engaging-side coupling device and a releasing action of the releasing-side coupling device, and including a shift control portion (82) to control a shift-down action of the step-variable transmission portion in a predetermined mode of hydraulic control of the engaging-side and releasing-side coupling devices, wherein the shift control portion controls the engaging-side and releasing-side coupling devices in a non-vehicle-driving control mode during the shift-down action of the step-variable transmission portion in a non-driving state of the vehicle, the shift control portion switching the mode of hydraulic control from the non-vehicle-driving control mode to a vehicle-driving control mode where the vehicle is switched from the non-driving state to a driving state within a predetermined length of time after a moment of initiation of the shift-down action, and maintaining the non-vehicle-driving control mode where the vehicle is switched to the driving state after the predetermined length of time has passed, while limiting a torque of the drive power source during the shift-down action to a predetermined value in the non-vehicle-driving control mode.

An irregular ground travelling vehicle includes a drive source and a transmission. The transmission includes: a drive shaft; a multiple disc clutch that connects/disconnects power from the drive source to the drive shaft; a driven shaft; a plurality of gear-position gear trains provided between the drive shaft and the driven shaft; a plurality of engaging clutches that enable power transmission of each of the plurality of gear-position gear trains; a transmission case that accommodates the drive shaft, the driven shaft, the plurality of gear-position gear trains, and the plurality of engaging clutches; an oil storage portion in which oil used for hydraulic control of the multiple disc clutch and the engaging clutch is stored at a bottom portion of the transmission case, the oil storage portion having a deepest portion located at a center in a vehicle left-right direction of the oil storage portion in a vehicle mounted state; and an oil strainer having a suction port located in the oil storage portion.

A transmission system for a vehicle, including an input configured to couple to a prime mover of the vehicle; a first gear ratio; a second gear ratio; a first dynamic controllable clutch operable in an engaged state, a disengaged state, and a one-way clutch state; a second dynamic controllable clutch operable in the engaged state, the disengaged state, and the one-way clutch state; an output; and a controller comprising instructions stored in non-transitory memory that are executable by the controller to: adjust a state of the first DCC and the second DCC to selectively engage the first gear ratio and the second gear ratio for providing torque transfer from the input to the output of the transmission system.

An irregular ground travelling vehicle includes a drive source and a transmission. The transmission includes: a drive shaft; a multiple disc clutch configured to connect or disconnect power from the drive source to the drive shaft; a driven shaft; gear-position gear trains between the drive shaft and the driven shaft; engaging clutches configured to enable power transmission of each of the gear-position gear trains; a transmission case that accommodates the drive shaft, the driven shaft, the gear-position gear trains, and the engaging clutches; an oil storage portion configured to store oil for hydraulic control of the multiple disc clutch and the engaging clutches at a bottom portion of the transmission case, the oil storage portion having a deepest portion at a center in a vehicle left-right direction of the oil storage portion in a vehicle mounted state; and an oil strainer having a suction port in the oil storage portion.