| 摘要 |
PURPOSE:To attempt a decrease of noises leaking out of a valve body without declining responsiveness of a valve mechanism by forming a communicating route to make an atmospheric air route closed by a closing member communicate with the atmosphere in an input shaft as well as installing a closing member to close the atmospheric route. CONSTITUTION:In a tandem braking toggle joint, front & rear diaphragms 13, 14 are respectively stretched on the rear surface of each power pistons 11, 12 as well the front & rear power pistons 11, 12 are respectively connected to a valve body 6. And, an input shaft 29 interconnected with a brake pedal is connected to the right end part of a valve plunger 17 slidably installed on the valve body 6. Then, on the input shaft 29, a rubber-made bellows-shaped cover 40 is fixed across the external peripheral part of its front member 37 and a cylindrical part 2a of a rear shell 2 to enable an atmospheric route 6b to be closed. Also, a communicating route 41 is formed across the front member 37 and the center member 38 of the input shaft 29 so as to communicate the atmospheric communicating route 6b of the valve body 6 to the atmosphere by closing this route by this cover 40. |
