Patent · US Expired

Variable camshaft timing for internal combustion engine

US5002023A · kind A · utility

93Cited by
23References
30Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 16, 1989
Grant dateMar 26, 1991
Priority date
Expiry dateOct 16, 2009

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02B2075/027
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

A variable camshaft timing arrangement for an internal combustion engine in which a camshaft, for example, an intake valve operating camshaft in a dual camshaft system, is advanced or retarded in its position relative to the crankshaft and to the exhaust valve operating camshaft in reaction to torque pulsations in such intake valve operating camshaft. The other camshaft of the dual camshaft engine has a sprocket oscillatingly mounted thereon. The other camshaft also has a bracket or another sprocket keyed thereto and the bracket or another sprocket is chain driven by the rotation of the crankshaft. A pair of single acting hydraulic cylinders interconnect the oscillating sprocket and the bracket or other sprocket, with the piston ends of the cylinders pivotably attached to the oscillating sprocket and with the body ends of the cylinders pivotably attached to the other sprocket or bracket. The cylinders act in opposite directions and are hydraulically interconnected so that one extends as the other retracts and vice versa. The hydraulic system includes a control valve which is controlled by an engine controller to selectively permit one of the cylinders to extend, and the other to re…

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