Internal breathing spring braking air chamber

The invention discloses an internal breathing spring braking air chamber, which is safe and reliable and is long in service life. The internal breathing spring braking air chamber comprises a front cavity and a rear cavity, the front cavity is arranged between a front cylinder and a middle shell, the rear cavity is arranged between a rear cylinder and the middle shell, a large piston is disposed in the rear cavity, an adjusting screw stem is disposed in the middles of the rear cylinder and the large piston, a piston barrel is arranged at the rear end of the adjusting screw stem, a cavity body is arranged in the middle of the piston barrel, a small push plate is disposed at the tail end of the piston barrel, an air suction hole is arranged on the piston barrel, a small piston is disposed in a cavity body at the tail of the piston barrel, a cavity body is arranged at the front end of the small piston, a return spring is arranged in the cavity body, a valve block with a hole in the middle is arranged at the fron