Patent ID: 11951958
Assignee: ZF CV SYSTEMS EUROPE BV
Field: Transport (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. A piston tube assembly (17) for a spring brake actuator (1), the piston tube assembly (17) comprising:
a first tubular body (35) having a contoured inside surface profile (55) for non-rotationally guiding a running nut (21) of a mechanical release mechanism (19, 21), and
an internal breather valve (41) mounted to the piston tube assembly (17) for allowing fluid transport into and out of the piston tube assembly (17) and any volume in fluid communication therewith,
wherein the piston tube assembly (17) further comprises a second tubular body (37) that is made of a different material than the first tubular body (35),
wherein the second tubular body encloses the first tubular body (35) and mechanically supports the first tubular body (35),
wherein the internal breather valve (41) is mounted to the first tubular body (35);
wherein the first tubular body (35) includes a head section (39) and a recess (51) disposed in the head section (39) for accommodating the internal breather valve (41).