Toyota Jidosha Kabushiki Kaisha

Toyota Jidosha Kogyo Kabushiki Kaisha

Toyota Jidoshi Kabushiki Kaisha

Hideki Yasue

Kagenori Fukumura

Hiromichi Kimura

Daisuke Inoue

Tadashi Tamura

Katsumi Kono

Kenji Matsuo

Hiroji Taniguchi

Hiroki Kondo

Ryoji Habuchi

Yuji Hattori

Yoshiaki Yamamoto

Hiroshi Morioka

Kunio Morisawa

Hiroshi Ito

Yoshinobu Soga

Yasunari Nakamura

Kenichi Yoshizawa

Yutaka Taga

Kunihiro Iwatsuki

Seitoku Kubo

Zenichiro Mashiki

Shinya Nakamura

Yoshio Shindo

Masami Sugaya

Isao Takagi

Yusuke Ogata

Yuji Kashihara

Hirofumi Kubota

Hirofumi Nakada

Hiroya Tanaka

Tetsuo Hamajima

Yukio Hamano

Syoichi Sayo

Shinji Kasuga

Michitaka Kakamu

Keita Sakurai

Hiromichi Kumura

Shinichi Matani

In a vehicular belt-driven continuously variable transmission, belt squeezing force is inhibited from becoming excessive and a safety factor, with respect to belt slip, of belt squeezing force applied to a transmission belt () is reduced to a value that is less than or equal to 1.5 by reducing a pressure receiving area (S) of an output side hydraulic cylinder (). As a result, a centrifugal hydraulic pressure canceller chamber on a secondary pulley side () can be eliminated thus simplifying the structure of the vehicular belt-driven continuously variable transmission, while belt squeezing force can be appropriately controlled.

Vehicular belt-driven continuously variable transmission and control method thereof

A control device for a drive line of a vehicle, in which a drive line from a power source to drive wheel includes a wheel control for controlling the speed of the wheels, and a connection mechanism for increasing/decreasing a torque transmission capacity between the power source and the drive wheels. The control device includes a trouble detector for detecting that the wheel control is in a situation unable to control the speed of the wheels normally. A braking detector detects that a braking operation to brake the rotation of the wheels is executed. And, a torque interruption control reduces the torque transmission capacity by the connection mechanism, when it is detected by the trouble detector that the wheel control cannot control the speed of the wheels normally and when it is detected by the braking detector that the braking operation to brake the rotation of the wheels is executed.

Controller for driving system of vehicle

A driving system of a motor vehicle includes a driving power source that generates power, and a belt-and-pulley type continuously variable transmission that transmits the power received from the driving power source to drive wheels while changing a first speed of rotation of an input shaft thereof to a second speed of rotation of an output shaft thereof. The driving system further includes a speed changing mechanism provided between the driving power source and the continuously variable transmission so as to increase or reduce a speed of rotation of the driving power source during forward running of the vehicle.

Driving system of motor vehicle

A vehicle planetary gear device including a sun gear, a carrier, a ring gear, a clutch drum, clutch plates axially slidably fitted in the drum, a backing plate fixedly disposed in the drum on one side of a series of clutch plates, and a piston axially movable fitted in the drum and disposed on the other side of the series of clutch plates, and wherein the ring gear is fixedly fitted in the drum with its engaging teeth held in engagement with engaging grooves of the drum, and at least one retainer ring is fixed on the drum and disposed in contact with the teeth of one-piece member consisting of the ring gear and the backing plate, whereby axial movements of the backing plate and the ring gear relative to the drum are prevented by the at least one retainer ring.

Planetary gear device for vehicle, having clutch drum provided with retainer ring

A shift control apparatus for controlling a continuously variable transmission device including a continuously variable transmission mechanism having rotary elements and operable to transmit a rotary motion of a drive power source of an automotive vehicle to a drive wheel of the automotive vehicle, such that a speed ratio of said mechanism is continuously variable, the shift control apparatus includes a power-transmission-state determining device for determining whether the mechanism is placed in a non-power-transmitting state, a speed-ratio determining device for determining whether the mechanism is placed in a lowest-speed position, a rotation-stop detecting device for determining whether the rotary elements are at rest, and a compulsory-speed-ratio-change implementing device for effecting a compulsory shift-down action of the mechanism toward the lowest-speed position when the mechanism is placed in the non-power-transmitting state while the mechanism is not placed in the lowest-speed position and while the rotary elements of the mechanism are at rest.

Transmission shift control apparatus arranged to perform compulsory shift-down action of continuously variable transmission

A control apparatus for feedback-controlling an engaging action of a clutch disposed between an engine and a transmission of an automotive vehicle, wherein an engaging force control device is operated upon an engaging action of the clutch, for determining a control amount and feedback-controlling the engaging action on the basis of the determined control amount such that the clutch is placed in a desired state of engagement, and a control amount limiting device is operated to limit the determined control amount when the determined control amount has changed to cause an engaging force of the clutch to be reduced.

Apparatus for controlling clutch between vehicle engine and transmission

When the temperature of operating fluid of an actuator is low, a target input rotation speed lower limit value (NinL) is set. The lower limit value (NinL) is greater than a lower limit value set for a normal temperature of operating fluid. A target input rotation speed (Nint) is calculated from the state of running of a vehicle, such as the amount of operation of an accelerator, the vehicle speed, etc. If the target input rotation speed is lower than the lower limit value (NinL), the target input rotation speed is reset to the lower limit value (NinL). As a result of a control that includes the above-described steps, the speed ratio &ggr; becomes relatively high before the vehicle stops. Therefore, even if the speed ratio-changing rate is low, the speed ratio (&ggr;) can be brought to or near a maximum value (&ggr;max) before the vehicle stops. Thus, reductions in the speed ratio-changing rate caused by low temperature of the operating fluid of the actuator can be curbed.

Shift control apparatus and shift control of continuously variable transmission

A hydraulic control system including: a rotating speed raising unit for raising the rotating speed of the prime mover while the transmission is not rotated by the prime mover, to increase an output volume of the hydraulic pump; at oil pressure instructor for outputting a plurality of instruction signals of different pressure instruction values to the valve modulating mechanism while the output volume of the hydraulic pump is increased; an oil pressure detector for detecting the oil pressure to be modulated and fed to the transmission, at a plurality of pressure levels; and a learning corrector for learning and correcting the instruction signals on the basis of the outputted pressure instruction value and the detected oil pressure detected.

Hydraulic control system for transmissions

A method and apparatus for controlling a continuously variable transmission of a motor vehicle includes a controller that controls the speed ratio of the continuously variable transmission in accordance with a predetermined shift condition. The method and apparatus perform shift control in a specific manner during an operation of an anti-lock brake system, for example, by smoothing at least one of the rotational speed of the input shaft and the rotational speed of the output shaft, reducing a rate of change in the speed ratio during down shifting, restricting upshifting of the CVT, increasing an amount of hydraulic oil delivered from an oil pump, and/or increasing belt clamping force.

Method and apparatus to control continuously variable transmission of motor vehicle

A hydraulic circuit cleaning apparatus has a hydraulic circuit that includes an oil pump, an oil passage to which the oil pressure ejected from the oil pump is supplied, and a pressure regulator device connected to the oil passage for regulating the oil pressure in the oil passage. The apparatus cleans the hydraulic circuit by using a cleaning liquid. A discharge oil passage is connected to a discharge port of the pressure regulator device, so that the cleaning liquid is discharged out of the hydraulic circuit via the discharge oil passage.

Hydraulic circuit cleaning apparatus and method

A speed change control system for a continuously variable transmission, for controlling a gear ratio by deciding an abrupt acceleration demand of a driver, to effect an abrupt speed change when it is decided that the driver demands an abrupt acceleration. The speed change control system comprises: a drive state decider for deciding that the vehicle has changed from a driven state to a drive state, when said abrupt acceleration is demanded at the driven state; and a speed change controller for controlling said continuously variable transmission to effect said abrupt speed change, after said drive state decider decides that the vehicle has changed from the driven state to the drive state.

Shift control system for continuously variable transmission

An apparatus and a method control a belt-type continuously variable transmission of a vehicle having a continuously variable speed ratio, which is a ratio of a rotation speed of an input shaft to a rotation speed of an output shaft. The speed ratio of the transmission is controlled by changing a groove width of each of the pulleys, and a belt clamping pressure applied to at least one of the pulleys to clamp the torque transfer belt also is controlled. Furthermore, the speed ratio of the transmission is set to a low-load speed ratio when it is determined that control of the belt clamping pressure has failed and the belt clamping pressure is raised to a high level. The low-load speed ratio is predetermined so that a load applied to the torque transfer belt is substantially minimized.

Control apparatus and method of belt-type continuously variable transmission

A shift control system for a continuously variable transmission, in which a road load on a vehicle is detected, the lower limit speed is set according to the detected road load, in which a target input speed, as set according to the running state of a vehicle, is restricted with the set lower limit speed, and in which the gear ratio of the continuously variable transmission is controlled so that the actual input speed may be equal to the target input speed restricted. The target input speed is restricted after the actual input speed is more than the lower limit value, when the road load is light, and said target input speed is restricted irrespective of the actual input speed when the road load is heavy.

Shift control system for continuously variable transmissions

A control apparatus is provided in a vehicle equipped with a power source and a continuously variable transmission. The continuously variable transmission is connected to the power source. The control apparatus includes a target power determinator, a target revolutions determinator, a determining device, a setting device and a target torque determinator. The target power determinator determines a target power of the power source. The target revolutions determinator determines target revolutions on the basis of the target power. The determining device determines whether the vehicle is a transient driving condition or not. The setting device sets the target revolutions as setting revolutions when the determining device determines that the vehicle is not in the transient driving condition. The setting device sets revolutions different from the target revolutions as the setting revolutions when the determining device determines that the vehicle is in a transient driving condition. The target torque determinator determines a target output torque of the power source on the basis of the target power and the setting revolutions. Since the vehicle is controlled in accordance with the driving condition of the vehicle, a jerky feeling can be avoided and ride quality or drivability of the vehicle is prevented from being deteriorated, even when the vehicle is in a transient driving condition.

Control apparatus of vehicle equipped with a continuously variable transmission and control method of the same

An apparatus for controlling the pressure of a hydraulically operated frictional coupling device which is released or engaged to achieve a shifting action of an automatic transmission, by first rapidly reducing or increasing the pressure to a predetermined level, holding the pressure at this level for a predetermined time and then continuously reducing or increasing the pressure to complete the shifting action, wherein a learning compensation device is provided to update, by learning compensation, a selected control parameter influencing a pattern of change of the pressure of the coupling device during the shifting action such that the shifting action is achieved in a predetermined manner.

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Toyota, Japan

Hideki Yasue