The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 06, 2007
Filed:
May. 18, 2006
Tamotsu Todo, Kanagawa, JP;
Shinichi Kawada, Kanagawa, JP;
Keisuke Takeda, Kanagawa, JP;
Mikihiro Kajiura, Tokyo, JP;
Tamotsu Todo, Kanagawa, JP;
Shinichi Kawada, Kanagawa, JP;
Keisuke Takeda, Kanagawa, JP;
Mikihiro Kajiura, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A variable valve system varies an operation condition of an engine valve by controlling an angular position of a control shaft in accordance with an operation condition of the engine. The system has an actuating mechanism for actuating the control shaft. The actuating mechanism comprises a threaded shaft that is rotated about its axis in accordance with the operation condition of the engine; a nut member operatively engaged with the threaded shaft, so that upon rotation of the threaded shaft the nut member runs axially along the threaded shaft; a link mechanism provided between the control shaft and the nut member, so that the axial movement of the nut member along the threaded shaft induces a rotational motion of the control shaft; and a biasing mechanism that biases the nut member relative to the threaded shaft at least at a predetermined range of the operation condition of the engine valve.