Single-cavity piston type air brake valve of diesel engine braking system of commercial vehicle

The utility model discloses a single-cavity piston type air brake valve of a diesel engine braking system of a commercial vehicle. The single-cavity piston type air brake valve comprises a pedal assembly (1), a middle piston (2), a valve body (3) and a valve assembly (4), wherein a filter (6) is arranged in an air inlet of the valve body (3). The single-cavity piston type air brake valve of the diesel engine braking system of the commercial vehicle improves the product cleanness, obviously enhances the product working performance and reliability, reduces the fault rate from 4% to 0.5%, and lays the foundation to the large-batch assembly of various vehicles.