Patent ID: 6378543
Filing Date: 2002-04-30
Classification: B21K,B23P,F01L,Y10T

Abstract:
A method of manufacturing a hollow poppet valve, comprising the steps of press-forming a metal shaped like a cup in a cold state; drawing said cup-shaped metal in a cold state to form, from a same metal, a cylindrical stem portion having a fillet area opened like a flare at one end there of wherein said fillet area has a fire contacting, valve face and an open edge portion opposite of said fire contacting valve face, said open edge portion having a wall thickness greater than a wall thickness of said stem portion and said fillet area; and welding a cap having a wall thickness less than said open edge portion onto the open edge portion of the fillet area such that said cap is supported solely by said fillet area and said weld joint and said metal forming said valve face has and HV of no less than 300.