| 摘要 |
<p>The invention mainly concerns a housing for receiving a reaction disc and a pneumatic brake servo unit comprising such a housing equipped with its reaction disc. A pneumatic brake servo unit is provided with means adapted to counter an excessively fast feed of the pneumatic piston when the brake is actuated, liable to cause the re-opening of the communication channel between the front and rear chambers of the pneumatic brake servo unit. The invention is characterised in that it consists in using the resiliency of a reaction disc (39) to counter an excessively fast initial feed of the piston (11). In the preferred embodiment, the substantially incompressible reaction disc (39) is received in a housing (47) whereof the internal volume is greater than the volume of the disc (39). The deformation of the disc (39) during a initial braking phase, deforms the disc so that it fills up entirely its housing (47) such that it can perform, during a subsequent braking phase, its conventional role of reaction disc. The application of the reaction disc (39) on the distributing plunger or any other part integral with the control rod controlling the valves, limits the feeding speed of the pneumatic piston when the brake is actuated and prevents or limits undesired reopening of the communication channels between the front and rear chambers of the pneumatic brake servo unit. The invention is particularly applicable to the car industry, and mainly to brake manufacturing.</p> |
