Nissan Motor Company Limited

Masaki Shimakura

Takashi Shibayama

Chiaki Harada

A first pump (21) which supplies a required flow amount for speed ratio control and a second pump (22) which supplies a flow amount which is re-cycled to an oil cooler in order to cool the oil are driven at the same time by a common motor (23). A required discharge amount for the first pump (21) is calculated depending on driving conditions and a required discharge amount for the second pump (22) is calculated depending on driving conditions. The motor (23) is controlled to a rotation speed so that a discharge amount is produced which satisfies the larger of the two required pump discharge amounts calculated above. In such a way, pump rotation speeds are controlled so that the required discharge amount is produced depending on driving conditions which enables reductions in electricity consumption and noise.

Oil pump controller for automatic transmission

A speed ratio control operation of an automatic transmission for a vehicle is controlled by using an oil pressure supplied from a oil pump (16). At least a circuit (22) which sets a rotation speed of the oil pump (16) to a first pump rotation speed in order to maintain a necessary minimum line pressure to control a variable mechanism, a stationary vehicle condition determination circuit (24) which determines that the vehicle is operating under the conditions that the brake is operated and vehicle speed is below a fixed value, and a circuit (23) which sets a second pump rotation speed which is lower than the first pump rotation speed when stationary vehicle conditions are met are provided. The rotation speed is lowered to the second pump rotation speed when the vehicle stationary conditions are met which results in reduced energy consumption and reduced noise pollution.

Growing community of inventors

Kanagawa, Japan

Masaki Shimakura