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:
Jan. 09, 2001
Filed:
Jan. 27, 1999
Ken Asakura, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
A variable valve timing apparatus for engines. Included are a phase adjustor for adjusting the rotational phase of a camshaft relative to a crankshaft and a lift adjustor for axially moving the camshaft. The phase adjustor has a timing pulley rotated synchronously with the crankshaft and a housing fixed to the timing pulley. A vane rotor rotated synchronously with the camshaft is arranged in the housing to define a first pressure chamber and a second pressure chamber in the housing. Hydraulic fluid is delivered to the first and second pressure chambers through oil conduits to rotate the vane rotor with respect to the housing and change the rotational phase of the camshaft relative to the crankshaft. The oil conduits extend through the timing pulley. This prevents the axial movement of the camshaft from affecting the hydraulic pressure of the pressure chambers. Accordingly, the valve timing is varied accurately.