Hitachi, Ltd.

Hitachi Car Engineering Co., Ltd.

Yutaka Takeuchi

Yuzo Kadomukai

Takehiko Kowatari

Eisuke Wayama

Yasuhiro Kamimura

Kenji Ono

Yuki Ejiri

Norihiro Isozaki

Masahiko Soshino

Hitoshi Andoh

Makoto Iida

Shigeo Tamaki

Naozumi Hatada

A lightweight, low cost throttle body and throttle valve placed in the body, both formed of resins, that resolve the problem of excessively large gap formation is disclosed. Circumferentially oriented filler contained in a resin forming a throttle valve compensates to make the radial linear expansion coefficient of the throttle valve substantially equal to that of a bore. Grooves are formed on concentric circles in the throttle valve to orient filler circumferentially. A throttle valve provided with circumferentially oriented filler can be formed by impregnating an aggregate formed by circumferentially arranging the filler with a resin and curing the resin. A rib is formed in a part near a throttle shaft to control molding shrinkage so that the roundness of the bore is small.

Throttle body

The invention is intended to simplify a default mechanism of a throttle valve opening and closing device for the purpose of improving mountability of the device to a vehicle. When a motor generate no driving forces, a throttle valve is held in a position () by a return spring. In this position, gaps are formed between the throttle valve and a wall surface of an intake passage. Spherical recesses are formed in parts of the wall surface of the intake passage. In a position () where the throttle valve is opposed to the spherical recesses, the gaps are minimized in an operating range of the throttle valve.

Throttle valve opening and closing device

Growing community of inventors

Hitachinaka, Japan

Yutaka Takeuchi