A current control device brings, after a target current has been changed to an upper side, a solenoid into a full-on state at a first timing that arrives in a predetermined control transition cycle shorter than an on-off cycle, determines whether an excitation current has become equal to or larger than a full-on threshold larger than the target current, brings the solenoid into a full-off state at a first timing that arrives in a predetermined energization switching cycle shorter than the on-off cycle after the excitation current has become equal to or larger than the full-on threshold, determines whether the excitation current has become equal to or smaller than a full-off threshold smaller than the target current, and causes a transition to a steady control at a first timing that arrives in the control transition cycle after the excitation current has become equal to or smaller than the full-off threshold.

A drive device for a PTO shaft includes a parking switch to detect a parking state of a vehicle body, a permission switch constituted of a self-returning switch and connected to the parking switch, the permission switch being configured to be switched to permit driving a PTO shaft, the PTO shaft being configured to be driven by a power of a prime mover disposed on the vehicle body, and a first switch device to be switched to enable the PTO shaft to be driven when the permission switch is switched to permit driving the PTO shaft under a state where the parking switch detects the parking state of the vehicle body.

The present invention is a hydraulic pressure control device for an automatic transmission that performs a gear shift by switching between engagement and disengagement of a plurality of friction engagement elements and includes solenoid valves, provided corresponding to the friction engagement elements, respectively, that switches between engagement and disengagement of the friction engagement elements by switching between supply and non-supply of hydraulic pressures to the friction engagement elements, and a control device that switches between supply and non-supply of the hydraulic pressures to the friction engagement elements by supplying a predetermined control current to the solenoid valves, in which the control device supplies a fixation preventing current lower than the control current to at least one of the solenoid valves corresponding to the friction engagement elements in a disengagement state of the plurality of friction engagement elements.

A drive device for a PTO shaft includes a parking switch to detect a parking state of a vehicle body, a permission switch constituted of a self-returning switch and connected to the parking switch, the permission switch being configured to be switched to permit driving a PTO shaft, the PTO shaft being configured to be driven by a power of a prime mover disposed on the vehicle body, and a first switch device to be switched to enable the PTO shaft to be driven when the permission switch is switched to permit driving the PTO shaft under a state where the parking switch detects the parking state of the vehicle body.

A working vehicle includes a first hydraulic clutch connected to the first traveling shaft, a second hydraulic clutch connected to the first traveling shaft separately from the first hydraulic clutch, a first gear mechanism to transmit, to a second traveling shaft, power from the first hydraulic clutch when the first hydraulic clutch is engaged and not to transmit, to the second traveling shaft, power from the first hydraulic clutch when the first hydraulic clutch is disengaged, and a second gear mechanism to transmit, to the second traveling shaft, power from the second hydraulic clutch when the second hydraulic clutch is engaged and not to transmit, to the second traveling shaft, power from the second hydraulic clutch when the second hydraulic clutch is disengaged.

An electro-hydraulic control system for a multispeed transmission having a plurality of torque-transmitting mechanisms includes a controller for operably controlling the transmission, a fluid source for supplying hydraulic fluid, and a plurality of torque-transmitting mechanisms being operably selected between an applied and an unapplied state to achieve a plurality of ranges including at least one reverse, a neutral, and a plurality of forward ranges. The system includes a plurality of trim systems having pressure control solenoids and trim valves. The system may also include one or more shift valves disposed in fluid communication with the fluid source and being capable of moving between stroked and de-stroked positions. In any given range, only two of the plurality of torque-transmitting mechanisms may be applied. Moreover, three of the plurality of pressure control solenoids are normally high solenoids, and the remaining solenoids are normally low solenoids.

An electro-hydraulic control system for a multispeed transmission having a plurality of torque-transmitting mechanisms includes a controller for operably controlling the transmission, a fluid source for supplying hydraulic fluid, and a plurality of torque-transmitting mechanisms being operably selected between an applied and an unapplied state to achieve a plurality of ranges including at least one reverse, a neutral, and a plurality of forward ranges. The system includes a plurality of trim systems having pressure control solenoids and trim valves. The system may also include one or more shift valves disposed in fluid communication with the fluid source and being capable of moving between stroked and de-stroked positions. In any given range, only two of the plurality of torque-transmitting mechanisms may be applied. Moreover, three of the plurality of pressure control solenoids are normally high solenoids, and the remaining solenoids are normally low solenoids.

The present invention is a hydraulic pressure control device for an automatic transmission that performs a gear shift by switching between engagement and disengagement of a plurality of friction engagement elements and includes solenoid valves, provided corresponding to the friction engagement elements, respectively, that switches between engagement and disengagement of the friction engagement elements by switching between supply and non-supply of hydraulic pressures to the friction engagement elements, and a control device that switches between supply and non-supply of the hydraulic pressures to the friction engagement elements by supplying a predetermined control current to the solenoid valves, in which the control device supplies a fixation preventing current lower than the control current to at least one of the solenoid valves corresponding to the friction engagement elements in a disengagement state of the plurality of friction engagement elements.

An electro-hydraulic control system for a multispeed transmission having a plurality of torque-transmitting mechanisms includes a controller for operably controlling the transmission, a fluid source for supplying hydraulic fluid, and a plurality of torque-transmitting mechanisms being operably selected between an applied and an unapplied state to achieve a plurality of ranges including at least one reverse, a neutral, and a plurality of forward ranges. The system includes a plurality of trim systems having pressure control solenoids and trim valves. The system may also include one or more shift valves disposed in fluid communication with the fluid source and being capable of moving between stroked and de-stroked positions. In any given range, only two of the plurality of torque-transmitting mechanisms may be applied. Moreover, three of the plurality of pressure control solenoids are normally high solenoids, and the remaining solenoids are normally low solenoids.

An electro-hydraulic control system for a multispeed transmission having a plurality of torque-transmitting mechanisms includes a controller for operably controlling the transmission, a fluid source for supplying hydraulic fluid, and a plurality of torque-transmitting mechanisms being operably selected between an applied and an unapplied state to achieve a plurality of ranges including at least one reverse, a neutral, and a plurality of forward ranges. The system includes a plurality of trim systems having pressure control solenoids and trim valves. The system may also include one or more shift valves disposed in fluid communication with the fluid source and being capable of moving between stroked and de-stroked positions. In any given range, only two of the plurality of torque-transmitting mechanisms may be applied. Moreover, three of the plurality of pressure control solenoids are normally high solenoids, and the remaining solenoids are normally low solenoids.