Jatco Corporation

Jonggap Kim

Yasushi Yabe

Seiichiro Takahashi

Takeo Hiramatsu

Yoshihiro Kono

A hydraulic controller includes an actuator for electrically controlling the hydraulic pressure, a hydraulic-pressure sensing part for sensing an actual value of the hydraulic pressure in the actuator, and an ECU for controlling the actuator. The ECU includes a fundamental hydraulic-pressure value command part for carrying out setting and command of a fundamental hydraulic-pressure command value, a feedforward control part for calculating through an inverse filter a first target hydraulic-pressure command value in accordance with the fundamental hydraulic-pressure command value, a feedback control part for calculating a second target hydraulic-pressure command value in accordance with the sensed actual value of the hydraulic pressure and the fundamental hydraulic-pressure command value, and a target control-amount determination part for determining a target control amount of the actuator in accordance with the first and second target hydraulic-pressure command value, wherein the ECU controls the actuator in accordance with the determined target control amount.

Hydraulic controller and control method with pressure and oil-condition sensing and failure

A double piston and belt type continuously variable transmission comprises a primary pulley provided with a primary piston chamber and a primary clamp chamber; a secondary pulley provided with a secondary piston chamber and a secondary clamp chamber; and an endless belt operatively put around the primary and secondary pulleys. A switching circuit is arranged to connect both the primary and secondary clamp chambers to either one of the primary and secondary piston chambers, which shows a higher hydraulic pressure than the other.

Double piston and belt type continuously variable transmission

A hydraulic control apparatus of a belt-drive CVT, controlling a transmission ratio by changing respective effective rotation radii of driving and driven pulleys, includes vehicle information sensors; hydraulic actuators changing the respective rotation radii; and a control unit determining each fluid pressure command value provided for the pulleys, and controlling the hydraulic actuators based on the fluid pressure command values. The control unit acquires an actual displacement amount of one of the pulleys. When changing a transmission to the highest or lowest speed transmission, the control unit sets a target displacement amount of one of the pulleys; estimates a rapidly changing amount of the working fluid pressure, occurring at close to an end of the speed change; and corrects the fluid pressure command value by the rapidly changing amount at a time when a rate of the actual displacement amount with respect to the target displacement amount has reached a predetermined rate &#x3b1;.

Hydraulic control apparatus for belt-drive CVT of vehicle

A hydraulic pressure control apparatus of a belt-drive continuously variable transmission (CVT) for an automotive vehicle, includes a vehicular information detector that detects engine-and-vehicle operating conditions and a hydraulic actuator that regulates primary and secondary pulley pressures. A CVT control unit calculates a primary-pulley slip-limit pulley thrust and a secondary-pulley slip-limit pulley thrust based on information about the engine-and-vehicle operating conditions. The CVT control unit sets a primary-pulley-thrust command value to the primary-pulley slip-limit pulley thrust and calculates a desired secondary pulley thrust based on a desired transmission ratio, when a pulley ratio is greater than or equal to 1. The CVT control unit sets a secondary-pulley-thrust command value to the secondary-pulley slip-limit pulley thrust and calculates a desired primary pulley thrust suited to the desired transmission ratio, when the pulley ratio is less than 1.

Hydraulic pressure control apparatus of belt-drive continuously variable transmission for automotive vehicle

There is provided a start clutch control system for a vehicle, including a start clutch disposed between an engine and a transmission in the vehicle, a detection unit that detects vehicle running conditions including at least a vehicle speed, and a control unit that controls engagement and disengagement of the start clutch according to the detected vehicle running conditions. The control unit has a target torque determining section to determine a target torque transmitted by the start clutch with reference to the vehicle running conditions, a torque transmission characteristic setting section to set a transmission characteristic of the target torque differently depending on the vehicle speed, a phase compensating section to make a phase compensation for the torque transmission characteristic based on actual and target mathematical models of the vehicle, and a clutch control section to control the start clutch according to the phase-compensated torque transmission characteristic.

Growing community of inventors

Shizuoka, Japan

Jonggap Kim