| 摘要 |
A hollow poppet valve has a stem portion provided at one end thereof with a tip portion; a cap portion; and a flared fillet portion formed between the stem portion and the cap portion, wherein at least a part of the stem portion that connects to the fillet portion is a thin hollow cylindrical member, and the cap member is welded to the fillet portion. The cap member is thin and has an arcuate axial cross section. It is laser-beam welded to the seat-abutment portion formed at the open end of the fillet portion such that a weld bead is formed along the inner periphery of the interface of the mated ends of the members. The weld bead adds an extra weld depth to the weld, which increases the modulus of section of the welded regions of the cap member and the fillet portion and enhances their welding strength. |
