Jatco Corporation

Jatco Transtechnology Ltd.

Yoshichika Hagiwara

Hiroyasu Tanaka

Yusuke Kimura

Tatsuo Ochiai

Hirofumi Okahara

Yasutaka Kawamura

Katsumi Doihara

Jihoon Kang

Hironobu Waki

Toshiyasu Yamaguchi

Takamitsu Shimazu

Makoto Sawada

When a throttle is substantially fully open and startup is not underway, a CVT control unit () controls a speed ratio in accordance with a fully open speed change line. When the throttle is substantially fully open and startup is underway, the CVT control unit () controls the speed ratio in accordance with a fully open startup speed change line. When the throttle is substantially fully open, startup is underway, and the number of times the primary pulley rotation speed exceeds a belt assurance upper limit value exceeds an assurance frequency number, the CVT control unit () controls the speed ratio in accordance with the full throttle speed change line instead of the full throttle startup speed change line, even though the throttle is substantially fully open and vehicle startup is underway.

Speed change control device for belt type continuously variable transmission

There is provided an engine torque control apparatus that is comprised of a torque-down amount calculating section to which the throttle valve opening and the engine speed are inputted and which calculates the torque-down amount based on the inputted values, an inertia correction amount calculating section that calculates the correction amount for inertia of each component part (inertia discharged torque), a friction correction amount calculating section that calculates the correction amount for friction generated by a belt CVT (friction discharged torque), a torque-down amount correcting section that corrects the torque-down amount based on the calculated correction amounts, and an engine torque control section that controls engine torque. Since the engine torque is controlled with inertia and friction discharged torque of each component part being taken into account, the upper limit of the torque inputted to an automatic transmission can be accurately controlled to the value of the allowable input torque of the automatic transmission.

Engine torque control apparatus

A clutch engagement control device controls the engagement of a forward clutch () and reverse clutch () in an automatic transmission connected to an engine () in a vehicle. An inhibitor switch () outputs a range signal in accordance with a position range of a select lever (). A manual valve () supplies oil pressure selectively to one of the forward clutch () and the reverse clutch () by changing position in accordance with the position range of the select lever (). A controller () of the clutch engagement control device determines whether an unmatching range condition occurs in which the range of the select lever () indicated by the range signal and the range of the manual valve () do not match, when the range of the select lever () indicated by the range signal is a drive range or reverse range; and suppress an increase in engine rotation speed prior to engagement of the forward clutch or reverse clutch when the unmatching range condition occurs.

Clutch engagement control of automatic transmission

A CVT has a torque convener (T/C) speed ratio calculation section that determines the speed ratio from the engine speed and the primary pulley speed. The calculation section then calculates the torque ratio from the speed ratio. An input torque estimation section then estimates the input torque input into CVT from the torque ratio and the determined engine output torque. The T/C speed ratio calculation section, having a correction amount calculation section, reduces the speed ratio when the accelerator pedal is depressed to less than Np/Ne. Because the disparity with real value of the speed ratio occurring in the dead time of the respective revolution sensors can be decreased and the input torque properly estimated, slippage between the V belt and the variable pulley is prevented.

Control device for a continuously variable transmission

Growing community of inventors

Fuji, Japan

Yoshichika Hagiwara