Patent ID: 11964641
Assignee: ZF ACTIVE SAFETY US INC.
Field: Mechanical elements (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 9:
10. A parking brake for a wheel rotor having a brake pad associated therewith, comprising:
a housing defining a passage;
a piston provided in passage;
a spindle threadably connected with the piston; and
a clutch unit connected to the spindle, the clutch unit having a first condition allowing relative rotation between the spindle and the piston such that the piston is axially movable within the passage and into engagement with the brake pad in response to hydraulic pressure applied to the piston, the clutch unit having a second condition preventing relative rotation between the spindle and the piston such that piston remains engaged with the brake pad when hydraulic fluid pressure is removed from the piston,
wherein the clutch unit includes a hub rotatably connected to the spindle and roller bearings arranged around the hub, the roller bearings being spaced from the hub when the clutch unit is in the first condition to allow for rotation of the spindle, the roller bearings being urged against the hub when the clutch unit is in the second condition to prevent rotation of the spindle.