Patent ID: 9528563
Filing Date: 2016-12-27
CPC Classification: F16D

Claim Text:
1. A hydraulic vehicle brake with a parking brake device for motor vehicles comprising a brake housing in which a hydraulic service pressure chamber is delimited by a brake piston, wherein hydraulic pressure fluid can be applied to the hydraulic service pressure chamber for carrying out service brake operations so that the brake piston is actuatable along a longitudinal piston axis (A) in order to achieve a braking effect, wherein the parking brake device acts on the brake piston by means of an actuating device, which actuates the brake piston to perform parking brake operations by means of a rolling-element ramp gear that is driven by an electromechanical actuator, and holds the brake piston in the actuated position, wherein at least one spring element acts on the rolling-element ramp gear in order to bias the brake piston toward the actuated position, maintain an adjusted clamping force on the hydraulic vehicle brake, and compensate thermal shrinking effects of the hydraulic vehicle brake, wherein a two-step gear is interposed between the electromechanical actuator and the actuating device, the first gear step on the inlet side being connected to an output shaft of the electromechanical actuator and the second gear step on the outlet side being connected to the rolling-element ramp gear, and wherein the two-step gear is a combination of a crown gear and a worm gear, with the worm gear forming the second gear step and having a self-locking design.