Toyota Jidosha Kabushiki Kaisha

Aisin-warner Limited

Aisin-warner Kabushiki Kaisha

Toyota Jidosha Kogyo Kabushiki Kaisha

Toyota Jidosha Kabushiki

Seiichi Nishikawa

Yoichi Hayakawa

Kagenori Fukumura

Masao Kawai

Yoshiharu Harada

Jiro Motomura

Yutaka Taga

Masahiro Kojima

Kazuaki Watanabe

Akio Numazawa

Nobuaki Takahashi

Tadashi Saitou

Tadanobu Kumagai

Yasunari Iwata

Yoshinori Shibayama

Kenichi Yoshizawa

Kazuhiko Shibata

Ichio Sakai

Yuji Ichikawa

Yasuhisa Kamiya

Tamotu Kobatake

A method and an apparatus for controlling a vehicle automatic transmission which has a plurality of selectively established gear positions and is shifted to and temporarily held in a predetermined one of the gear positions other than the lowest-gear position, upon operation of a shift lever from its neutral position to one of drive positions, if a predetermined condition is satisfied within a preset time period after the shift lever operation. The transmission is generally shifted down to the lowest-gear position after it is held in the predetermined one gear position. This anti-squat shifting of the transmission responsive to the shift lever operation from the neutral position, contributes to reduction in the shifting shock and prevention of squatting of the tail or stern of the vehicle when the shift lever is moved from the neutral position to a drive position such as DRIVE, SECOND or LOW, in which the transmission is selectively placed in the two or more gear positions (e.g., 1st-gear, 2nd-gear, and 3rd-gear positions).

Apparatus and method for controlling automatic transmission for motor

A diagnostic system for detecting failure of rotational speed sensors incorporated in a central differential device of a four wheels drive vehicle for the purpose of controlling a lock-up clutch in the central differential device, wherein the rotational speed sensor for an output rotational member of the central differential device is checked, when the rotational speed detected thereby is lower than the rotational speed detected by the other rotational sensor, if the rotational speed detected thereby is continually zero over a period such as 10 seconds while the output of the other rotational speed sensor is above a certain low value.

Diagnostic system for rotational speed sensors in drive train of four

A transmission control system for controlling a transmission. The system has a main transmission with a speed changing mechanism and an output shaft, a substransmission connected to the output shaft, and a control system for receiving outputs from a number of sensors which sense the running state of the vehicle. The control system itself has two outputs, there being two separate hydraulic controls connected to the two system outputs, respectively. The two hydraulic controls control the speed changing mechanisms of the main and subtransmissions, respectively. Also provided is a hydraulic pressure source which supplies a working fluid to the two hydraulic controls. The control system determines whether the main and subtransmissions are in a transient period of the speed changing operation and, as long as one of the two transmissions is in the transient period, inhibits the speed changing operation of the other transmission.

Transmission control system

A device for supplying lubricating oil in a transmission mechanism, the transmission mechanism comprising: an input shaft; an output shaft disposed parallel to the input shaft; a first rotary body provided on the input shaft; a second rotary body provided on the output shaft; a transmission member for interlocking the first rotary body with the second rotary body; and, a transmission mechanism case forming a transmission mechanism chamber separated from the exterior for housing the transmission mechanism; and, the lubricating oil supply device comprising: a partition wall assembly with an opening disposed in the transmission mechanism case chamber and defining an oil chamber to contain the lubricating oil scattered by the rotation of the transmission mechanism through the opening; and, a lubricating oil supply passage connected to the oil chamber to supply the transmission mechanism with lubricating oil, the passage being disposed at a level lower than the opening, whereby oil scattered by operation of the transmission mechanism is collected in the oil chamber and supplied to the transmission member through the passage whenever the oil in the oil chamber is at a level higher than the passage.

Lubricating oil supply device for transmission mechanism

In a four wheel drive vehicle, a four wheel drive device receives rotational power from an engine and provides it to the combination of the front wheels of the vehicle and also to the combination of the rear wheels of the vehicle. A device is provided for selectively coupling the rotation of the combination of the front vehicle wheels and the rotation of the combination of the rear vehicle wheels. A control device is provided for this front/rear coupling device, and includes: (a) a means for detecting the rotational speed of the combination of the front wheels of the vehicle; (b) a means for detecting the rotational speed of the combination of the rear wheels of the vehicle; and: (c) a means for controlling the front/rear coupling device, so that its operation is substantially not restricted when the discrepancy between the rotational speed of the combination of the front wheels of the vehicle and the rotational speed of the combination of the rear wheels of the vehicle is not greater than a certain threshold value; while, when the discrepancy between the rotational speed of the combination of the front wheels of the vehicle and the rotational speed of the combination of the rear wheels of the vehicle is greater than the certain threshold value, coupling between the rotation of the combination of the front vehicle wheels and the rotation of the combination of the rear vehicle wheels is substantially prohibited. The method of operation of this device is also disclosed.

Device for controlling vehicle four wheel drive front/rear coupling

A transmission for a vehicle has a shift mechanism, a hydraulic actuator for operating the shift mechanism and a hydraulic control for supplying and discharging working oil to and from the hydraulic actuator to control the shift of the shift mechanism. The hydraulic control includes a flow regulating valve for regulating flow of the working oil supplied to the hydraulic actuator, as a function of pressure of the working oil supplied to the hydraulic actuator.

Hydraulic control for vehicle transmission

A transfer in combination with a transmission mechanism for a four wheel drive vehicle is provided comprising a first output shaft aligned with the transmission mechanism, a second output shaft extending parallel to the first output shaft, a power transmission mechanism for transmitting driving force from the first to the second output shaft, and a clutch coaxially mounted on the second output shaft for connecting and disconnecting the second output shaft to and from the power transmission mechanism. In addition to the clutch between the second output shaft and the power transmission mechanism, another clutch may be provided between the first output shaft and the power transmission mechanism. The transmission/transfer further includes parking locks for stopping the rotation of the first and second output shafts. A control apparatus is associated with the clutches between the first and second output shafts and the power transmission mechanism and includes a delay unit for providing a time lag between the engagements of the clutches.

Four wheel drive vehicle transfer and control apparatus

Herein disclosed is a method and apparatus for controlling a four-wheel drive vehicle wherein said method hydraulically controls a distribution of a drive force between the front and rear wheels of a four-wheel drive vehicle and a change of the gear ratio of an automatic transmission of the vehicle. After either the drive force distribution control or the gear ratio change control has been started, the other control is forbidden until a predetermined condition is satisfied. This control is either the lapse of a predetermined period of time or the end of one of the controls which is determined by the result of a comparison of the number of revolutions of the transmission or the result of a comparison of the hydraulic pressure.

Method and apparatus for controlling four-wheel drive vehicles

A fluid pressure actuator for a frictionally engaged unit of a vehicular transmission includes a first transmission and a second transmission coupled to the output side of the first transmission and provided with a speed step change mechanism which has a frictionally engaging element for engaging a rotary member to a fixed member in such a manner as to enable an optional disengagement between the rotary member and the fixed member. The fluid pressure actuator further has an annular cylinder for operating the frictionally engaging element and has an outer annular portion and an inner annular portion provided inside the outer annular portion coaxially therewith, an annular piston including an outer annular portion slidably fitted to the outer annular portion of the cylinder and an inner annular portion slidably fitted to the inner annular portion of the cylinder, an outer cylinder chamber defined by the outer annular portions of the cylinder and the piston, and an inner cylinder chamber defined by the inner annular portions of the cylinder and the piston and connected to the outer cylinder chamber through an orifice through which working oil is supplied to one of the cylinder chambers. A one-way valve is provided in one of the annular portions of the cylinder for causing external air to be drawn into the one oil chamber.

Hydraulic control of transmission

A main transmission has a transfer gear attached to its output shaft. The transfer gear provides two wheel high speed drive, four wheel high speed drive, and four wheel low speed drive. A control system controls the main transmission according to a detected speed mode of the transfer gear. The control system uses an electrical detector for sensing the speed mode of the transfer gear.

Shift condition detector for an automatic vehicle transmission

A transmission control device for controlling the operation of a transmission system including a main transmission and a sub transmission comprises a control circuit adapted for effecting a change-over of the main transmission between different speed gears in accordance with the level of the torque output from an engine when speed modes of the sub transmission are changed over. It is therefore possible to allow the main transmission to select a gear conformable to the gear ratio set in the sub transmission in accordance with the engine output torque, whereby it is possible to obtain optimum shifting characteristics. In addition, it is possible to widen the shiftable region for the sub transmission.

Transmission control having a plurality of speed changing ratios for

A hydraulic control system for an automatic transmission has an inhibitor valve which comprises a change-over valve having a first set position and a second set position and functioning to supply and discharge a hydraulic pressure to and from a hydraulic servomechanism for a friction engaging element through its movement between the first and second set positions; an arrangement for urging the change-over valve to the first set position; a plunger having a first set position and a second set position and functioning to bring the change-over valve into the second set position when the plunger is urged to the second set position. The inhibitor have functions to perform the supply and discharge of the hydraulic pressure to and from the hydraulic servomechanism in accordance with a first hydraulic signal and a second hydraulic signal through an arrangement which produces the first hydraulic signal for urging the change-over valve to the second set position and urging the plunger to the first set position. An arrangement produces the second hydraulic signal for urging the plunger to the second position; and an arrangement delays a discharge of the second hydraulic signal.

Hydraulic control system for automatic transmissions

A hydraulic control system for an automatic transmission, including a pressure source, a regulator valve for regulating the oil pressure from the source, a first hydraulic servo for setting the transmission in a high speed position upon receipt of output oil pressure of the pressure regulator valve, and a second hydraulic servo for setting the transmission in a low speed position upon receipt of the output oil pressure, wherein the hydraulic control system comprises:

Shift shock suppression in automatic transmission

A transmission control device for controlling the operation of a transmission which is composed of a main transmission portion and a sub transmission portion which is capable of manual change-over is disclosed. The control device inhibits the shifting operation of one transmission while the other transmission is in operation. This structure of the control device avoids the occurrence of synchronization of the shifts made by means of the main transmission portion and the sub transmission portion, and thereby eliminates the amplification of transmission shock caused by the synchronization of the shifts of the main transmission portion and the sub transmission portion, whereby optimum shifting characteristics are obtained.

Transmission control device

A front cover affixed to the pump impeller of a torque converter, provided with a flat annular flat annular surface to be engaged with the clutch disk of a direct-coupling clutch formed within the torque converter. The flat annular surface is formed in a flat and annular surface having a hard and compact metallographic structure by rolling a rolling tool made of a extremely hard material on the flat annular surface under a pressure and by thus causing plastic deformation of the flat annular surface. An intermediate part of an arcuate section of a small radius is formed between the periphery of said flat annular surface and a connecting part adjacent to the flat annular surface.

Growing community of inventors

Toyokawa, Japan

Seiichi Nishikawa