Hydraulic valve lifter

Claim 1

A hydraulic valve lifter for use in a valve train of an internal combustion engine, said lifter comprising: a first cylindrical body member having an inner cylindrical wall with an inlet port extending therethrough and having a top wall adapted to be disposed in engagement with a cam shaft; an annular guide sleeve fixed in said body member in spaced relation to said cylindrical wall to define an annular space therebetween; a second cylindrical body member having a bottom wall mounted for reciprocation within said annular guide sleeve, said bottom wall adapted to be in contact with a valve stem; a plunger member mounted for reciprocation within said second body member; spring means biasing said plunger member towards said top wall; said plunger member and said second body member defining a pressure chamber; said plunger member defining a reservoir chamber therein; first fluid passage means extending between said reservoir chamber and said annular space; second fluid passage means interconnecting said reservoir chamber and said pressure chamber; check valve means associated with said fluid passage means for permitting fluid flow only from said reservoir chamber to said pressure chamber; an annular channel member having an inverted U-shaped cross section secured between said cylindrical wall and said guide sleeve and defining an oil chamber extending between said inlet port and said first fluid passage means wherein said guide sleeve is comprised of a relatively thick member for obtaining rigidity and said annular channel member is made of relatively thin plate material for easy shaping and weight reduction.