Back structure for seat of motor vehicle, has shaft fixed with inertia reel belt, two flanges arranged in U-shaped region and connected with bar, and metal sheet and frame connected to shaft

摘要

The structure (30) has a shaft (35) fixed with an inertia reel belt (40). Two flanges (35a) are arranged in a U-shaped region and connected with a bar (35b). A metal sheet (31) and a frame (33) are connected to the shaft. A coding aperture (350) is formed in a coding metal sheet (42) of the inertia reel belt. Width of an upper portion of the coding aperture is greater than width of a bottom portion of the coding aperture.