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:
Oct. 10, 2000
Filed:
Mar. 16, 1998
Masanori Koda, Kanagawa, JP;
Unisia Jecs Corporation, Atsugi, JP;
Abstract
A camshaft phase changing apparatus for an internal combustion engine has a control valve interposed in a hydraulic circuit. The control valve controls the connection between one of first and second hydraulic passages and the hydraulic supply passage and the connection between the other of the first and second hydraulic passages to the hydraulic drain passage according to the engine driving condition. The first and second hydraulic passages are linked to a corresponding one of an advance-angle side hydraulic chamber and a retardation-angle side hydraulic chamber defined between a rotatable main body and a sleeve fitted on the camshaft. The control valve has a first port connecting the hydraulic drain passage to either the first or second hydraulic passage, and a second port connecting the hydraulic supply passage to the other of the first or second hydraulic passage. The first port has a cross-sectional area that is narrower than that formed on the second port when a cam phaser thereof is moved to adjust a rotational phase relationship between a rotary body and the camshaft.