| 摘要 |
An electropneumatic brake system for a railway vehicle having an electronic control unit that outputs a friction brake demand signal according to the difference between a brake command signal and a feedback signal representative of the effective dynamic brake, whereby the total dynamic and friction brake effort corresponds to the brake command signal. The brake system also includes a pneumatic operating unit having a pair of high-capacity, electropneumatic valves operated by the friction brake demand signal to regulate the pneumatic pressure at the brake unit directly, that is, without an intermediary relay valve. Such an arrangement provides better response and more accurate pressure feedback of the friction brake level to the electronic control unit. A service rate control choke is located ahead of the electropneumatic valves, which allows these valves to perform the emergency and wheel-slip control functions without requiring independent valves for this purpose, by virtue of their high-capacity capability. |
