Mazda Motor Corporation

Isuzu Motors Limited

Fujitsu Corporation

Mazada Motor Corporation

Isuzo Motors Limited

Mazda Motor Corporatioon

Hiroshi Yoshimura

Takuji Fujiwara

Kazuo Takemoto

Kozo Ishii

Masahito Kitada

Fumiaki Baba

Keiji Bota

Toshiya Sugimura

Kazuo Sasaki

Toshihisa Marusue

Toshifumi Koshizawa

Mitsutoshi Abe

Junzo Kuroyanagi

Youichi Iida

Kenji Kurisu

Kanji Okamoto

Akira Ohkawa

Satoshi Yamaguchi

Kenji Okamoto

Toshihiro Hattori

Junichi Doi

Hitoshi Kasai

Akihiro Shirata

Toshihiro Yamada

Koichiro Takeuchi

Kouzou Ishii

Shinichi Tanaka

Kozo Ishi

Fujiwara Takuji

Akihiro Shirate

Hidetoshi Kambara

A control apparatus for an engine and an automatic transmission controls a starting timing, a terminating timing, or methods of torque reduction of the engine during gear shifts. Using stored information such as a turbine speed signal, a gear shift signal, a degree to which a throttle valve is opened, a vehicle speed, an engine speed and so on, the control apparatus calculates an appropriate torque reduction which is performed by either retarding ignition timing or cutting fuel supplied to fuel injection valves. According to one embodiment of the invention, by detecting a variation ratio or differential value of turbine speed, a period of the torque reduction is started, ended, and kept within a proper timing. According to another embodiment of the invention, based on a 'chasing' state of an input torque of the transmission against the variation of engine load, the timing of torque reduction is changed. Finally, according to yet another embodiment of the invention, a light preceding torque reduction is performed prior to a more significant torque reduction, but only when shocks due to the gear shift tend to occur.

Torque control apparatus for engine and automatic transmission

A power train control system includes an automatic transmission shift control which detects an operational failure of an electric throttle valve based on an electric throttle opening. The transmission shift control governs or controls shifting of the automatic transmission, based on an electric throttle opening and a vehicle speed when no operational failure of the electric throttle valve is detected and based on a composite opening of an electric throttle opening and a mechanical throttle opening and a vehicle speed when operational failure of the electric throttle valve is detected.

Power train control system for motor-car

An automatic transmission shift control system includes a hydraulically controlled valve mechanism for connecting and disconnecting a supply of hydraulic pressure to frictional coupling elements. Connection and disconnection of the hydraulic pressure supply locks and unlocks the frictional coupling elements in order to automatically shift an automatic transmission into desired gears. A time regulator regulates a duration time for which the valve mechanism is kept actuated and with which a speed at which the frictional coupling element is locked changes. The time regulator is controlled so as to variably regulate the duration time according to conversion efficiency of a torque converter. This conversion efficiency is, for example, determined from a speed conversion ratio and a torque conversion ratio.

Control system for automatic transmission using torque converter speed

An automatic transmission includes a multi-speed transmission gear mechanism having an input shaft, an output shaft and a plurality of friction coupling elements. A hydraulic control system selectively supplies a hydraulic pressure to the friction coupling elements, thereby selectively applying the friction coupling elements to cause the transmission gear mechanism to shift to a speed which is determined according to a predetermined shift pattern. The control system sets a target hydraulic pressure to be applied to the friction coupling elements according to the kind of the shift to be effected and the engine load, and, when it is detected that the transmission gear mechanism is to make a backout upshift due to reduction in the engine load, increases the target hydraulic pressure by an amount which is determined according to the throttle opening and the turbine speed.

Hydraulic control system for controlling line pressure based on

A control system controls a second to third gear shift of an automatic transmission in an advantageous way. The transmission has a 3-4 clutch, which is locked under hydraulic pressure, and a 2-3 brake provided with a lock pressure chamber and an unlock pressure chamber. The 2-3 brake is locked when a hydraulic pressure is developed in the lock pressure chamber only and is unlocked when a fluid pressure is developed in the unlock pressure chamber and when a hydraulic pressure is released from both the lock pressure chamber and the unlock pressure chamber. Hydraulic pressure is released from the lock pressure chamber so as to unlock the 2-4 brake only when a second to third gear shift is needed for the first time after engine ignition simultaneously with application of pressure to the 3-4 clutch so as to lock the 3-4 clutch. Other than when a second to third gear shift is needed for the first time after engine ignition, pressure is supplied into the unlock pressure chamber while keeping the lock pressure chamber supplied with pressure so as to unlock the 2-4 brake.

Control system with band brake actuator for automatic transmission

A control system for an automatic transmission includes a main hydraulic line to which hydraulic pressure is introduced when a manual valve takes a reverse range position for reverse movement. First and second hydraulic lines are separated from the main hydraulic line, a first frictional element is connected with the first hydraulic line, and a second frictional element is connected with the second hydraulic line. An accumulator is disposed on the second hydraulic line, a shift valve is disposed on the second hydraulic line closer to the second frictional element than the accumulator, and a first drain port is formed on the manual valve for draining hydraulic fluid from the main hydraulic line when the manual valve is shifted from the reverse range to another range. A spool is disposed in the shift valve for moving to a position to shift the shift valve so that the second line is interrupted by the shift valve and divided between a second frictional element line and an accumulator line. A second drain port is formed in the shift valve for draining the hydraulic fluid in the second frictional element line when the spool moves to the position where the shift valve interrupts the second hydraulic line between the second frictional element line and the accumulator line. A shift shock can be suppressed in a shifting operation involving the reverse range.

Control system for automatic transmission

A hydraulic pressure control system for an automatic transmission includes a multiple transmission gear mechanism having a plurality of gear stages and frictional elements for switching power transmitting paths in the transmission gear mechanism, a hydraulic control mechanism for controlling engagement and disengagement of the frictional elements to establish one of said gear stages, and a line pressure control device for controlling line pressure of the hydraulic control mechanism. A speed detecting device for detects a speed of an input element of the transmission gear mechanism during shift operation of the shift gear stage in the transmission gear mechanism, and a compensation device compensates the line pressure in accordance with signal from the speed detecting device. The line pressure is compensated by a learning control to reduce a torque shock due to the shift operation.

Line pressure control system for automatic transmission

An automatic transmission line pressure control system controls line pressure in an automatic transmission equipped with a torque convertor for hydraulically coupling and uncoupling friction coupling elements of the automatic transmission. The automatic transmission line pressure control system regulates line pressure for selectively coupling and uncoupling the friction coupling elements so as to shift the automatic transmission into desired speed gears. The line pressure is forcibly dropped to a level lower than a level present before an occurrence of a manual shift-down operation when a shift-down sensor detects the occurrence of a manual shift-down. The line pressure is then raised as a speed sensor detects an increase in rotational speed transmitted the automatic transmission, thereby shifting the automatic transmission into desired speed gears.

Automatic transmission line pressure control system

An automatic transmission system includes a regulator for regulating line pressure delivered to friction coupling elements of a transmission mechanism. The friction coupling elements are selectively coupled and released, in combination, so as to shift gear ratios. A control device controls the regulator so as to provide a proper line pressure. The control device operates to learn a correction value for the line pressure which depends upon a shift-time it takes for the transmission to complete an up-shift and corrects the line pressure according to the correction value learned from an actual shift-time. Thus, an up-shifting of the transmission is completed in a desired shift-time. The correction of the line pressure in the learning control is practically performed when the number of engine cylinders for which fuel delivery is cut off is smaller than a predetermined number.

A fluid coupling for an automatic transmission includes an input element, an output element and a lockup clutch and is connected to a transmission mechanism. The lockup clutch can engage and disengage to operatively connect and disconnect the input element and the output element with and from each other. Further the lockup clutch can engage in slipping engagement to connect the input element and the output element in such a way as to allow the input element and the output element to rotate relative to each other to some extent. A control system causes the lockup clutch to engage in slipping engagement with a substantially fixed engaging force when the transmission mechanism upshifts while the lockup clutch is in slipping engagement, and to disengage when the transmission mechanism downshifts while the lockup clutch is in slipping engagement.

Control system for fluid coupling

A slip control system for a torque converter of an automatic transmission includes lock-up clutch device provided in a torque converter for connecting an input and output members of the torque converter directly. A torque detecting device detects a transmitted torque introduced into the output member of the torque converter, a speed difference setting device sets a target value of a rotation speed difference between the input and output members, a pressure difference control device controls a pressure difference between a releasing chamber and an engaging chamber of the lock-up clutch device, based on a predetermined relationship between the input torque and the speed difference so as to accomplish the target value of the speed difference, and a speed difference detecting device detects an actual speed difference between the input and output members. In a preferred embodiment of the invention, a compensatng device compensates the target value of the speed difference set by the speed difference setting device based on a deviation between the actual and target speed difference. A responsive slip control, therefore, can be accomplished.

Slip control system for torque converter of automatic transmission

An oil pressure control system for an automatic transmission employed in a vehicle comprises a device for producing line pressure, a device for supplying engaging friction elements in the automatic transmission with operating oil pressure obtained from the line pressure, a device for determining a pressure control variable based on operating condition of an engine with which the automatic transmission is coupled, a device for determining a supplemental control variable based on a duration of speed change or a state of speed change in the automatic transmission, a device for revising the supplemental control variable in accordance with the operating condition of the engine to produce a revised supplemental control variable, a device for revising the pressure control variable in accordance with the revised supplemental control variable to produce a revised pressure control variable, and a control device operative to control the line pressure in accordance with the revised pressure control variable when a specific speed change operation is performed in the automatic transmission.

Oil pressure control systems for automatic transmissions

A control system for a vehicle engine coupled with an automatic transmission, which comprises a detecting portion for detecting a condition of speed change operation in the automatic transmission, a speed sensor for detecting engine speed or turbine speed in the automatic transmission, a first period determining portion for determing a first period of time, in which the speed change operation is to be carried out, by calculation based on the speed detected by the speed sensor, a second period determining portion for determining a second period of time, in which the speed change operation is to be carried out, in accordance with a predetermined lapse of time after the condition of the speed change operation is selected, and a torque control portion operative to vary torque produced by the vehicle engine to suppress torque shock resulting from the speed change operation during the first period of time when a condition of shifting-up operation is detected by the detecting portion and to vary the torque so as to suppress torque shock resulting from the speed change operation during the second period of time when a condition of predetermined shifting-down operation is detected by the detecting portion.

Control systems for vehicle engines coupled with automatic transmissions

A hydraulic pressure control system for an automatic transmission includes a torque converter, a multiple transmission gear mechanism having a plurality of gear stages and frictional elements for switching power transmitting paths in the transmission gear mechanism, a hydraulic control mechanism for controlling engagement and disengagement of the frictional elements to establish one of the gear stages, and a line pressure control device for controlling line pressure of the hydraulic control mechanism in accordance with a vehicle operating condition. An engine torque detecting device detects an engine output torque, and a turbine speed detecting device detects a turbine speed of the torque converter. A shift condition detecting device detects a shift-up operation and a shift-down operation in the transmission, and the line pressure control device controls the line pressure in accordance with the engine torque in the shift-up operation and the turbine speed in the shift-down operation. A precise line pressure control can be accomplished for obviating torque shock at the time of the shift operation in the automatic transmission.

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Hiroshima, Japan

Hiroshi Yoshimura