Nissan Motor Company Limited

Jatco Corporation

Shigeki Shimanaka

Hiroyasu Tanaka

Satoshi Takizawa

Masato Koga

Masatoshi Akanuma

Junya Takayama

Mitsuru Watanabe

Tatsuo Wakahara

Yuji Kato

Shigeru Ishii

Hiroshi Yamaguchi

Masahiro Yamamoto

Shinsuke Nakazawa

Hiroshi Asano

Hiroshi Sasaki

Yoshihisa Kodama

Kazuhiro Ishigami

Hideharu Yamamoto

Yasutaka Kawamura

Yoshihide Shinso

Shinichi Takenouchi

Shuji Kurokawa

Takayuki Suzuki

Tateki Jozaki

Midori Yamaguchi

Tsuyoshi Yamanaka

Kosei Murata

Masaki Watanabe

Masahiro Iriyama

Takuichiro Inoue

Hirofumi Okahara

Toshiji Iida

Hisao Nobu

Takateru Kawaguchi

Katsumi Doihara

Kenichi Gotou

Hideki Oshita

Jihoon Kang

Youhei Ishikawa

Tetsuya Shimada

Takashi Hara

Hironobu Waki

Manabu Yamanaka

Donggyun Park

Shinich Takenouchi

Takeki Jozaki

Makoto Shiomori

In an oil pump control apparatus of a vehicle includes a first driving power source for propelling the vehicle, a first oil pump driven by the first driving power source, a second oil pump driven by a second driving power source, and a hydraulically-operated portion supplied with working oil from the first and second pumps, a look-ahead vehicle speed estimation section is provided for estimating, based on a vehicle running condition, a look-ahead vehicle speed, which may occur a given elapsed time later. Also provided is a second-oil-pump control section configured to predict, based on the look-ahead vehicle speed, whether a lack in discharge pressure produced by the first pump from a required hydraulic pressure, and further configured to start up the second pump, when it is predicted that a lack in discharge pressure of the first pump from the required hydraulic pressure occurs.

Oil pump control apparatus of vehicle

A control apparatus of a driving force in case of belt slipping includes a belt slip control detecting unit adapted to detect that the belt slip control is in execution, a belt contact radius ratio calculating unit adapted to calculate a belt contact radius ratio of the V-belt to the pulleys, and a power source output torque determining unit adapted to determine a target power output torque according to the belt contact radius ratio in execution of the belt slip control in response to signals from the belt slip control detecting unit and the belt contact radius ratio calculating unit.

Control apparatus of driving force in case of belt slipping for vehicle equipped with V-belt continuously variable transmission and control method thereof

A control apparatus of hybrid vehicle has a drive mode change section, a temperature detection section detecting a second engagement element temperature, and a second engagement element protection control section. The drive mode change section changes drive modes of a first drive mode in which the first engagement element is disengaged and the second engagement element is engaged then the vehicle travels by only a driving force of the motor, a second drive mode in which the first and second engagement elements are respectively engaged then the vehicle travels by both driving forces of the engine and motor, and a third drive mode in which the second engagement element is slip-engaged then the vehicle travels by a driving force transmitted through the second engagement element. The second engagement element protection control section keeps an engine rotating state regardless of the drive mode when the second engagement element temperature is high.

Control apparatus for hybrid vehicle

A control apparatus of hybrid vehicle has a drive mode change section, a deceleration detection section, an engine stall prevention control section, an engine stall prediction section, and an engine stall avoidance control section. The drive mode change section changes drive modes of EV drive mode, HEV drive mode and WSC drive mode according to a vehicle travel state. The engine stall prevention control section performs a coast-down shift which changes a transmission ratio of an automatic transmission to a lower transmission ratio upon deceleration of the vehicle. The engine stall prediction section predicts whether or not an engine stall occurs, during a travel in a HEV drive mode. The engine stall avoidance control section disengages at least one of first and second engagement elements when the occurrence of the engine stall is predicted by the engine stall prediction section.

A belt continuously-variable transmission control apparatus includes: a belt continuously-variable transmission including; a primary pulley arranged to receive a torque from a driving source; a secondary pulley arranged to output the torque to driving wheels; a belt wound around the primary pulley and the secondary pulley; a hydraulic pressure control section configured to control a hydraulic pressure of one of the primary pulley and the secondary pulley which is a capacity side, and thereby to bring the belt, the primary pulley and the secondary pulley to a slip state; and a torque control section configured to control the torque of the driving source, and thereby to bring the slip state to a predetermined slip state.

Control apparatus for belt-type continuously-variable transmission

When a speed of a vehicle is less than 8 km/h, an upshift determination condition is established, an idle switch signal is turned off, and a downshift is detected, an operating speed of the step motor is limited. Thereby, since the operating speed of the step motor is limited even when the vehicle is rapidly decelerated and re-accelerated before a pulley ratio is returned to a lowest value Lo, a shift speed of the downshift performed in the re-acceleration is lowered, and no slippage occurs in a V-belt between pulleys.

Shift control system in belt-type continuously variable transmission

In case information such as an actual gear ratio is not stored in an EEPROMdue to a trouble of a backup power sourceor like when an initialization operation of a step motoris performed at the time of start of a vehicle or during stoppage of the vehicle, an output torque of an engine is limited before the initialization operation. Thereby, even if an accelerator is depressed during the initialization operation of the step motorin which a sufficient primary pulley pressure cannot be ensured, the output torque of the engine is limited, so that torque inputted to a V-belt type continuously variable transmission is small and slippage does not occurs between the primary pulley and a secondary pulley.

Engine torque control system

During a downshift of a belt-drive continuously variable transmission, occurring owing to vehicle deceleration, a CVT controller foretells that a slippage between a drive belt and each of primary and secondary variable-width pulleys tends to occur, when a primary pulley pressure is less than a first predetermined pressure level and a primary pulley speed is less than a first predetermined rotational speed. When the belt slippage has been foretold, the CVT controller inhibits the primary pulley pressure from dropping by setting an actual transmission ratio calculated before a set time period from a time when the slippage has been foretold or a transmission ratio of a relatively higher speed side as compared with a ratio-change operating state obtained when the slippage has been foretold, to a desired transmission ratio, or by relatively rising a line pressure as compared with a line pressure level produced when the slippage has been foretold.

Slippage prevention apparatus of belt-drive continuously variable transmission for automotive vehicle

An abnormal oil pressure reduction determining device has an oil pressure sensor which detects a real oil pressure, a sensor which detects a vehicle running state, and a controller which sets an oil pressure command value for an oil pressure control mechanism. The controller computes the lower limiting oil pressure which is possible in the present vehicle running state, and when the real oil pressure is less than this lower limiting oil pressure and the pressure difference between the real oil pressure and oil pressure command value exceeds a reference value, determines that there is an abnormal pressure reduction due to a fault in the oil pressure control mechanism. Even if the oil pressure of the transmission has dropped abnormally due to some reason, the abnormal oil pressure reduction determining device determines the situation without fail.

Abnormal oil pressure reduction determination device for vehicle transmission

In control apparatus and method for an automotive vehicle, the vehicle having a continuously variable transmission associated with a vehicular engine and including a belt that transmits a revolution of a primary pulley to a secondary pulley that is enabled to make a gear shift by modifying a pulley ratio between the primary and secondary pulleys with a hydraulic, a determination is made as to whether a belt slip between at least one of the primary and the secondary pulleys occurs and an output section outputs a signal to command an engine control unit to increase an engine speed by a predetermined engine speed when the belt slip is determined to occur.

Control apparatus and method for automotive vehicle in which a belt-type continuously variable transmission is equipped with a belt slip preventive feature

A system for controlling a V-belt type CVT is constructed to change a first position of a step motor to a second position of the step motor corresponding to a second target shift ratio if it is determined that the primary-pulley pressure fails to reach a predetermined value. The second target shift ratio is on the high-speed side with respect to a third position of the step motor corresponding to a third target shift ratio to be achieved if it is determined that the primary-pulley pressure reaches the predetermined value.

System and method of controlling V-belt type continuously variable transmission

A shift control system for a vehicle automatic transmission includes a vehicle speed sensor for detecting a vehicle speed, and a first control means normally performs a shift control of the transmission so that a target speed ratio of the transmission is achieved, which is determined based at least on a vehicle speed detected by the vehicle speed sensor. The shift control system further includes a second control means that properly performs shift control of the transmission when the vehicle speed sensor is in trouble, by generating a command for holding or changing a current speed ratio based on an input rotation speed of the transmission and/or driver's accelerating or decelerating operation of the vehicle.

Shift control system for automatic transmission

A speed change ratio control unit for a continuously variable transmission that uses a step motor as a driving actuator of a speed change control valve that compares a variable ASTP representing a step position of the step motor and a step position BSTP of the step motor that is necessary for realizing a desired speed change ratio at every predetermined operation cycle, and if ASTP&#x2260;BSTP is satisfied determines that a step-out has occurred on the step motor.

Speed change ratio control unit for continuously variable transmission

A shift control system of a toroidal CVT for a vehicle is arranged to calculate a command gear ratio by adding a desired gear ratio and a torque shift compensation quantity for compensating a difference between the desired gear ratio and an actual gear ratio which difference is generated by a shifting operation of the toroidal CVT, and to set a magnitude of the torque shift compensation quantity employed in an automatic shift range to be larger than a magnitude of the torque shift compensation quantity employed in other shift range except for the automatic shift range when the actual gear ratio is in a first gear ratio region except for a second gear ratio region including a largest gear ratio.

Shift control system of continuously variable transmission

A starting shift control system for a continuously variable transmission is provided which includes a control unit having a high start judgment device for judging whether or not a high start in a high speed side gear ratio is caused on the basis of a comparison between the generated number of the input rotation pulses and the generated number of the output rotation pulses from the time a first vehicle starting operation is performed after start of a prime mover, and a high start control device for restricting downshifting from the high speed side gear ratio to a target gear ratio when a start of the vehicle is judged to be the high start. A starting shift control method is also provided.

Starting shift control system and method for continuously variable transmission

Growing community of inventors

Hadano, Japan

Shigeki Shimanaka