| 摘要 |
<p>When a booster is inoperative, a first atmosphere valve (S1) and a second atmosphere valve (S2) are both closed to block a communication of an orifice passage (36) with a variable pressure chamber (B); at the commencement of operation of the booster, the first atmosphere valve (S1) opens while the second atmosphere valve (S2) remains closed to allow the atmosphere to be introduced into the variable pressure chamber (B) through the orifice passage (36), followed by an opening of the second atmosphere valve (S2) to allow the atmosphere to be introduced into the variable pressure chamber (B) through the second atmosphere valve (S2) and the first atmosphere valve (S1), such an arrangement allowing the occurrence of oscillations of or abnormal sounds from a valve mechanism to be prevented during the initial phase of the brake operation. <IMAGE></p> |
