| 摘要 |
<p>An air brake system for railway trains is of the known direct releasing kind in which a controlled fall in pressure in a brake pipe determines the auxiliary reservoir pressure admitted to a brake cylinder, thereby achieving a predetermined braking effect. A subsequent increase in the brake pipe pressure causes an abrupt release of the brakes. The system includes a distributor in which a sealing valve is adapted to close on braking so as to isolate the brake pipe from an auxiliary reservoir. The invention provides that on brake release opening of the sealing valve is delayed for a predetermined time interval so as to allow sufficient build-up of brake pipe pressure in the main control valve chamber (9) to ensure full brake release. The sealing valve has an enlarged chamber (25) with a choke-controlled opening.</p> |
