| 摘要 |
PURPOSE:To equalize the thickness of a throttle passage part over the whole body, by bulging the throttle passage part while applying pressure to it in the axial direction after being bent, in case of a device made up of forming the throttle passage part and a silencer chamber as one body upon machining a metallic tubular body. CONSTITUTION:A central part of the metallic tubular body 151 cut in the specified length is bulged by means bulging operation, forming a silencer chamber 151a. And, both ends of this tubular body 151 is contracted by means of spinning opertion, forming each of throttle passage parts 154 and 155. Then, the throttle passage part 155 on one side is formed into an L-shaped form by means of bending operation, making the bend part 155a produce some crushing. Afterward, a silencer 105 is put in molding blocks 9-11, and hydraulic pressure is applied to the inside the silencer 105 while compressing each end part of these throttle passage parts 154 and 155 in the axial direction by pistons 12 and 13 moving inside these molding blocks 9-11, thus bulging operation takes place. With this constitution, the crushing of the bend part 155a is corrected and its thickness is equalized. |
