Monitoring and alarming device for returning process of urban railway vehicle

The invention relates to a monitoring and alarming device for the return process of an urban railway vehicle. The monitoring and alarming device comprises a power supply detection module, a time-delay relay, an intermediate relay, a sound-light alarm lamp and the like, when braking of the urban railway vehicle is not relieved or applied, a braking relieving signal is converted into a low level from a high level, a coil of the time delay relay is powered off, the time delay closing normally-closed contact is closed in a time delay mode, and the braking relieving sound-light alarm lamp gives out a sound-light alarm prompt. When the urban railway vehicle is braked emergently, an emergency braking signal is converted from a high level to a low level, the normally closed contact of the intermediate relay is disconnected instantaneously, and the emergency braking sound-light alarm lamp gives out a sound-light alarm prompt; and when the bus voltage of the urban railway vehicle is lower than a voltage threshold value