| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a drum brake device capable of ensuring effect of a stable brake by controlling a braking force in accordance with force of a brake both upon braking a forward movement and upon braking a backward movement. <P>SOLUTION: The drum brake device has a shoe driving cam 7 for mechanically controlling the braking force in accordance with the force of the brake acting on an anchor pin 10 from brake shoes 3 and 4. Pin contact surfaces 81 and 83 of cam holes 76b, 77b, 76c and 77c in the side of the anchor pin 10 on which cam pins 21 and 23 abut upon braking are formed on guide surfaces on which abutting positions of the cam pins 21 and 23 on the cam holes when cam plates 76 and 77 rotate in such directions as to reduce operating forces of the shoes gradually come near to the center of the anchor pin 10. <P>COPYRIGHT: (C)2003,JPO</p> |
