| 摘要 |
PURPOSE:To realize the simplification and inexpensiveness of manufacture by forming an annular edge portion by conducting the bending processing of the peripheral edge portion of a through-hole piercingly provided at a reinforcement plate, toward the outer side part over the whole periphery, forming at the same time an annular welding portion by conducting the projection welding of the annular edge portion to a booster shell. CONSTITUTION:The head part 35 of a connection bolt 33 is put on the inner surface of a reinforcement plate 30 that is put on the end wall inner surface of a booster shell 1a and has an inward annular flange portion 30a at its outer periphery edge, and is joined through a first annular welding portion 39 surrounding the shaft part of the bolt 33. The reinforcement plate 30 and the head part 35 are joined through a second annular welding portion 41 surrounding the shaft portion 36 likewise. In this instance, a through-hole 37 into which the shaft portion 36 is penetrated is piercingly provided at the reinforcement plate 30. Also, the bending processing of the peripheral edge portion of the through-hole 37 toward the outer side part over the whole periphery is conducted so that the outer side opening edge of the through-hole 37 may become an annular edge portion 42 that rises toward the outer side. In addition, by conducting the projection welding of the annular edge portion 42 onto the end wall inner surface of a booster shell 1a, this welding portion is made to be the first annular welding portion 39. |
