SUB-MUFFLER AND MANUFACTURING METHOD OF SUB-MUFFLER

摘要

A manufacturing method of a sub-muffler (1, 201) includes a tubular body shaping step (S3), a central part spinning machining step (S5, S7, S26, S27), and a diameter reduction machining step (S8, S28). In the tubular body shaping step (S3), a cylindrical body (2, 202) is formed by rolling a plate material (70). In the central part spinning machining step (S5, S7, S26, S27), the cross-sectional shape of a central part (20, 220) of the cylindrical body (2, 202) is machined into a rectangular shape by performing a spinning machining in which a rotating roller (88) is moved along a rectangular trajectory (T3, T6) while pressing the rotating roller (88) onto the central part (20, 220) of the cylindrical body (2, 208). In the diameter reduction machining step (S8, S28), the diameter of an end (80, 81, 280, 281) of the cylindrical body (2, 208) is reduced.

主权项

1. A manufacturing method of a sub-muffler comprising:
a tubular body shaping step of rolling a plate material, and thereby forming a cylindrical body; a central part spinning machining step of performing a rectangular spinning machining in which a rotating roller is moved along a rectangular trajectory while pressing the rotating roller onto a central part of the cylindrical body, and thereby machining the central part so that a cross-sectional shape of the central part becomes a rectangular shape; and a diameter reducing step of reducing a diameter of an end of the cylindrical body.