Toyota Jidosha Kabushiki Kaisha

Jtekt Corporation

Aisin Aw Co., Ltd.

Toyo Kogyo Co., Ltd.

Haruhiko Shibata

Masashi Hattori

Masahiro Ito

Masahiko Suzuki

Yoshihiro Mizuno

Yusuke Ogata

Kenichi Mori

Naoki Okoshi

Hidenobu Yamaguchi

Fumitake Suzuki

An oil pump includes a first spill passage formed on a side surface () of a pump chamber () to communicate a hydraulic pressure chamber () with a first high pressure discharge passage () when the entire hydraulic pressure chamber () is positioned between the first high pressure discharge passage () and a first low pressure discharge passage (). Therefore, when the hydraulic pressure chamber () passes between the first high pressure discharge passage () and the first low pressure discharge passage (), the hydraulic pressure inside the predetermined hydraulic pressure chamber () escapes to the first high pressure discharge passage () through a first spill passage (), so a hydraulic pressure value inside the hydraulic pressure chamber () is maintained at the pressure value inside the first high pressure discharge passage (). As a result, fluid is inhibited from flowing into the hydraulic pressure chamber () from the first high pressure discharge passage () through a space between inner peripheral teeth () and outer peripheral teeth ().

Vehicular internal gear type oil pump

A vehicular power transmitting system including an oil pump constructed to sufficiently reduce a required drive torque. A high-pressure-port discharge amount of first and second high-pressure passages of the oil pump is determined such that an amount of consumption of working oil of relatively high pressure can be afforded only by the high-pressure-port discharge amount, during steady-state running of a vehicle in which engine speed is not lower than a predetermined threshold value corresponding to a predetermined lowest target input shaft speed of a continuously variable transmission for its shifting control. The pressure of the working oil discharged from first and second low-pressure discharge passages is kept at a predetermined low level, and the required drive torque of the oil pump is sufficiently reduced.

Vehicular power transmitting system

Growing community of inventors

Okazaki, Japan

Haruhiko Shibata