Patent ID: 6978710
Filing Date: 2005-12-27
Classification: B60T

Abstract:
1. A pneumatic booster in which the interior of a housing is divided into a constant pressure chamber and a variable pressure chamber by a power piston, and a plunger disposed inside a valve body which is connected to the power piston is moved by an input rod, thereby opening valve means to introduce a working gas into the variable pressure chamber, thus generating a pressure differential between the constant pressure chamber and the variable pressure chamber, whereby a thrust force generated in the power piston by the pressure differential is applied to an output rod through a reaction member, and a reaction force from the output rod which acts on the reaction member is partly transmitted to the input rod, wherein an annular elastic member is interposed between the reaction member and the plunger, and control means are provided to restrict radially inward deformation of the elastic member, thereby restricting compression of the elastic member in the movement direction of the plunger, under normal conditions, and to permit radially inward deformation of the elastic member, thereby permitting compression of the elastic member in the movement direction of the plunger, when a movement amount of the plunger in relation to the valve body reaches a predetermined value.