| 摘要 |
PURPOSE:To contrive space saving, to improve a return of a brake shoe and to prevent adhesion and a deffective return of a cam from occurring, by overlapping a cam collar at the initial stage of incorporation and reducing a cam width of a cam of a cam component as narrow as possible. CONSTITUTION:When braking is disengaged, brake shoes 2 and 2' are returned by a shoe return spring 4, through which each of a cam component 5, cam collars 12 and 12', a adjust gear 14 and a feed claw 22 are rotated clockwise in a body for restoration to an original position respectively. When the braking is disengaged at the time of the restoration, the cam component 5 is rotated easily for the rostoration to an original position through bounce of the return spring 4, return peculiarity of the brake shoes 2 and 2' is favorable, and adhesion and deffective return are not generated as a cam width of a cam part 5a is narrow and the valve of b/a based on a relation to a contact point M among the center O of a cam shaft, the cam collars 12 and 12' and shoe webs 2b and 2b' is small. |
