Patent · US Expired

Variable valve timing apparatus

US6170448A · kind A · utility

23Cited by
6References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 27, 1999
Grant dateJan 9, 2001
Priority date
Expiry dateJan 27, 2019

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF01L2001/34426
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.