MECHANICAL DRUM BRAKE FOR AUTOMOBILE

摘要

The present invention relates to a mechanical parking drum brake for a vehicle. A leading brake shoe (16) and a trailing brake shoe (18) are coupled to a front of a backplate (14) by using an anchor pin (28) and return springs (20, 40, 42) so that each of the leading brake shoe (16) and the trailing brake shoe (18) rotates around an axis of the anchor pin (22) by a cam (30) having a cam shaft (28) to perform braking. A through hole (48) having a larger diameter than the cam shaft (28) is provided in the backplate (14). A first bracket (52) having a guide hole (50), which is elongated left and right, and a second bracket (56) spaced apart from the first bracket (52) to maintain a predetermined distance and having a shaft hole (54) to rotatably couple the cam shaft (28) are sequentially coupled to a back of the through hole (48) so that the cam shaft IS rotatable around shaft holes (24, 54) of the dust cover (12) and the second bracket (56) while movable left and right by the large through hole (48) of the back plate (12) and the guide hole (50) of the first bracket (52). Thus, an optimal brake force can be achieved by applying optimal force to each of the leading brake shoe (16) and the trailing brake shoe (18) and also a braking effect (output force/input force) is improved to a level equivalent to an effect of a hydraulic parking drum brake of a wheel cylinder structure.