| 摘要 |
PURPOSE:To contrive the miniaturization of the spring by a method wherein two or more bent and wound parts of a piece of wire for a spring are arranged in a load working direction, and along with this, the bent and wound parts are made to incline by a given angle to the load working direction. CONSTITUTION:When brake shoes 2, 3 of a drum brake are applied to a shoe return spring 1 which pulls the shoes 2, 3 to a direction to attract them each other, the spring 1 is composed of hooks 4, 5 arms 6, 7 and a spring pat 8. Said spring part 8 is constituted with a plurality of round bent parts 17 wherein a wire for a spring is bent in a ring type, arranged in multilayer manner to the direction connecting shoes 2, 3. Each round bent part 17 is formed with the maximum inclination of an inclined part 18 having 45 deg. or less so that the spring part 8 may be a flat plate type. Accordingly, the width (b) of the spring part 8 can be comparatively made small and the fitting of a tension spring to a narrow and small place can be easily performed. |
