SOUND ABSORBER AND ITS PROCESS OF MANUFACTURE

PROBLEM TO BE SOLVED: To enable an easy judgement to be carried out about a positive connection performed through a laser welding when a metallic processed product is welded to form a shell shape, enable an easy adjustment work for a manufacturing line even in the case that a certain unsatisfactory part is found at the laser welding connected part and further enable a material cost, its weight to be reduced and a technical diversification to be carried out.SOLUTION: This invention relates to a sound absorber 1 in which an upper half body 3 where a circumferential wall 32 is vertically arranged from a circumferential end of a base plate 31 and a lower half body 4 where a circumferential wall 42 is vertically arranged from a circumferential end of the base plate 41 are abutted to each other at opening end edges, a welded part 5 is formed at the abutted portions around its entire circumference through laser welding and it is preferable that the upper half body 3 and the lower half body 4 are formed with opening expanded portions 33, 43, extremity end edges of the opening expanded portions 33, 43 are formed with small round portions 34, 44 curved outwardly, and the abutted small round portions 34, 44 are melted by laser welding to form the welded part 5. 【課題】金属製の加工品を溶接してシェルを形成する際に、レーザー溶接で確実に接合されたことを容易に判断することができ、レーザー溶接による接合に不具合が生じた場合にも製造ラインの調整作業を容易に行うことを可能にすると共に、材料コストの低減、重量の低減、技術の多様化を図ることができる。【解決手段】基板３１の周端から周壁３２が立設する上側半体３と基板４１の周端から周壁４２が立設する下側半体４とが開口端縁で相互に突合され、突合部分に全周に亘るレーザー溶接で溶接部５が形成されてシェル２が構成されている消音器１であり、好ましくは上側半体３、下側半体４に口拡げ部３３、４３を形成し、口拡げ部３３、４３の先端縁に外方へ湾曲する小アール部３４、４４を形成し、突合された小アール部３４、４４をレーザー溶接で溶かすことにより、溶接部５を形成するとよい。【選択図】図３