| 摘要 |
<p>PROBLEM TO BE SOLVED: To enhance the stability of braking efficiency, in this duo-servo type drum brake device. SOLUTION: This drum brake device is equipped with a pair of input pistons 502 and 520 where a wheel cylinder 5 widening an interval between two opposed ends on one side of a pair of brake shoes 1 and 10 presses each end of these paired brake shoes 1 and 10 by dint of hydraulic pressure being fed to a first pressure chamber 110, and a pair of reaction pistons 51 and 55 closing a normally open-type input control valve 54, receiving the hydraulic pressure from a master cylinder at the base end side while receiving an anchor reaction via two levers 3 and 30 at the tip side, and at a time when the anchor reaction is reached to the specified multiplying factor against the hydraulic pressure from the master cylinder, it is displaced, supplying the first pressure chamber with the hydraulic pressure, respectively.</p> |
