Patent ID: 6988442

Claim:
A brake actuator comprising: a service chamber and a spring chamber disposed in tandem, said spring chamber being defined by a flange case having a radially outwardly extending annular flange and a head having a radially outwardly extending annular flange; wherein the annular flange of said flange case and the annular flange of said head define a widened annular opening having a width and a narrowed passage having a width smaller than the width of the widened annular opening; a diaphragm having a widened outer periphery with a width greater than the width of the narrowed passage, the widened outer periphery of said diaphragm being sandwiched between the annular flange of said flange case and the annular flange of said head and disposed within the widened annular opening, said diaphragm comprising a reinforcing member embedded in or attached to an outer surface of the widened outer periphery thereof radially outwardly of the narrowed passage, the reinforcing member comprising a ring having a generally circular cross-section and being formed of a material which is more resistant to deformation than a material of which said diaphragm is formed so as to inhibit the widened outer periphery of said diaphragm from pulling radially inwardly through the narrowed passage between the annular flange of said flange case and the annular flange of said head; and wherein said reinforcing member comprises a reinforcing member composed of a plurality of discrete segments.