US 2025/0334157 A1 · PISTON FOR AN ACTUATOR MECHANISM, COMPRISING A NUT AND A BUSHING

Abstract

A piston of an actuator mechanism, the piston including a worm gear mechanism nut, the nut including an outer peripheral wall and a nut thread for cooperating, directly or via balls, with a worm gear mechanism screw; a bushing integral with the nut and at least partially covering the outer peripheral wall of the nut, the bushing comprising a cylindrical guide zone intended to come into close sliding contact with an inner guide wall of a guide cylinder of the actuator mechanism. The nut comprises at least one annular shrink-fit bearing surface, the bushing includes at least one shrink-fit zone shrink-fitted onto the annular shrink-fit bearing surface. The guide zone has a larger outer diameter than the shrink-fit zone and overlaps a covered portion of the outer peripheral wall of the nut without contact or shrink-fitting.

Claims20

Dependent claims

A piston of an actuator mechanism, the piston comprising:

a nut of a worm gear mechanism, defining a reference axis, an outer peripheral wall and a nut thread intended to cooperate, directly or via balls, with a screw of the worm gear mechanism;
a bushing secured to the nut and at least partially covering the outer peripheral wall of the nut, the bushing comprising a cylindrical guide zone intended to come into close sliding contact with an inner guide wall of a guide cylinder of the actuator mechanism;
wherein the nut comprises at least one annular shrink-fit bearing surface, the bushing comprises at least one shrink-fit zone shrink-fitted onto the at least one annular shrink-fit bearing surface, the cylindrical guide zone having an outer diameter greater than that of the at least one shrink-fit zone and overlapping, without contact or shrink-fitting, a covered portion of the outer peripheral wall of the nut.

A brake actuator mechanism, comprising:

a guide cylinder;
a ball screw mechanism, comprising a screw and a nut defining a reference axis of the brake actuator mechanism, coaxial with the guide cylinder, and balls, the screw having at least one screw thread forming a raceway for the balls, the nut having a nut thread forming an outer helical raceway for the balls and an outer peripheral wall;
and
a bushing secured to the nut and at least partially covering the outer peripheral wall of the nut, the bushing coming into close sliding contact with an inner guide wall of the guide cylinder;
wherein the nut comprises at least one annular shrink-fit bearing surface, the bushing comprises at least one shrink-fit zone shrink-fitted onto the annular shrink-fit bearing surface, the cylindrical guide zone having an outer diameter greater than that of the shrink-fit zone and overlapping, without contact or shrink-fitting, a covered portion of the outer peripheral wall of the nut.

2 more elements

Dependencies are inferred from the claim text.

Piston for an actuator mechanism, comprising a nut and a bushing

Life of this patent

Piston for an actuator mechanism, comprising a nut and a bushing

Life of this patent

Abstract

Claims20