Emergent relay valve assembly of automotive

The utility model relates to an emergency relay valve assembly of an automobile, which comprises an upper valve body and a lower valve body, wherein a control opening on the upper valve body is communicated with a control chamber on the lower valve body; a piston is arranged in the control chamber, and is connected with a pressure opening valve which is arranged in the lower valve body. The piston is a hollow ladder-shaped piston with a big upper end and a small lower end, and is divided into an upper ladder and a lower ladder. The control chamber is a ladder-shaped control chamber corresponding to the plunger, and is divided into an upper chamber, a middle chamber and a lower chamber by a piston. The upper end of the piston is closed, the bottom end of the piston is provided with a flow throttling hole which is communicated with the lower chamber of the control chamber and the lateral wall of the lower ladder of the piston is provided with an air through hole and is communicated with the middle chamber of the control chamber. The utility model causes the air pressure of an air outlet of the emergency relay valve to have a certain leading quantity, the air pressure of the air outlet can be dynamically changed into zero in a leading way in the process of braking and the driving safety is ensured.