空气制动系统概述

为了使列车能够有效减速，需要全列同时制动。这种制动可以通过列车的空气制动系统实现。每辆车辆的两端都配备有一根制动软管，当车辆连挂时，软管可以握手的方式互相连接在一起。这样，机车驾驶员就能够使用单个机车的控制装置操纵整个列车的制动。

制动系统中的气压由机车上的风泵提供，并通过控制阀、管道和软管传递到整个列车。为了简单起见，该系统可以看作由三个独立的部分组成：主风缸、制动管和制动缸。

Main Reservoir

主风缸是机车上的一个大容积高压罐，由机车上的空气压缩机保持高压，为系统的其他部分提供压力。

Brake Pipe

制动管是一套由阀门、管道和软管组成的系统，贯穿整个列车，由主风缸为其加压。在每个车厢连接处，可以通过底部的一个称为折角塞门的阀门手动开启或关闭空气流动，可防止气压泄漏到大气中。在正常行车状态下，制动管保持5帕的压力。

Auxiliary Reservoirs

Auxiliary reservoirs are medium volume vessels found on each individual vehicle. Pressurized by the brake pipe, they store pressure that is ready to apply brakes on demand. While auxiliary reservoirs can take a long time to charge, they practically never run out during regular operation.

Brake Cylinders

每节车厢都有一个或多个自带的制动缸。制动缸是低容积的气压缸，对一个活塞施加压力，从而使车辆的制动靴与车轮接触并实现制动。一个三通阀会对制动管中的压力变化作出反应，从每辆车上的专用容器——即副风缸，向制动缸供压。

Train Charging

Due to leaks , no brake components can remain pressurized indefinitely. It usually takes some time to bring the components of unused vehicles to their nominal, high pressure level, before they can be set in motion. The two biggest factors are the main reservoir, which will charge as quickly as the respective compressor is capable to, and auxiliary reservoirs, which may take a long time to charge, depending on how many vehicles there are in the train.

Adding additional locomotives to the train to improve charging speeds is a viable option, as is revving the engine .

Train Brake Application

Train brake is applied by a control device found in motorized rail vehicles. Applying brakes on a fully charged train functions by air getting dumped from the brake pipe to the atmosphere. This forces auxiliary reservoirs to feed their stored pressure to brake cylinders, pressing brake shoes against the wheels.

Train Brake Release

通过操作机车制动手柄，司机可以控制制动管的压力，间接影响列车中每个制动缸的内部气压。将列车制动手柄向“应用”方向移动会将制动管中的气压排出大气。每辆车上的三通阀会允许副风缸中的风压进入制动缸，开始制动。若将列车制动手柄向“缓解”移动，主风缸中的风压会给制动管加压。这会将副风缸风压重新填满，且三通阀会将制动缸中的气体排出大气缓解制动。

Automatic Stop Safety Mechanism

Crucial safety feature of the compressed air brake system is that, in case of vehicle connection getting severed, such as due to a derailment , brake pipe pressure will be lost to the atmosphere, resulting in automatic full brake application on both remaining train parts. This is integral to the compressed air brake system design in trains.