Patent ID: 8151946
Filing Date: 2012-04-10
Classification: B64C

Abstract:
1. A rotor brake for a helicopter, the rotor brake comprising: a braking-force actuator; a brake fluid reservoir; a first hydraulic line connecting the braking-force actuator and the reservoir; an electromechanical piston control element having a piezoelectric element, a piezoelectric amplifier, and a pump piston, wherein the piezoelectric element is controllable by the piezoelectric amplifier and is configured to move the pump piston, the electromechanical piston control element connected to the first hydraulic line using a second hydraulic line and a third hydraulic line between the braking force actuator and the brake fluid reservoir, the second hydraulic line having an inlet valve and the third hydraulic line having an outlet valve; and a release valve positioned in the first hydraulic line and interposed between the second and third hydraulic lines; wherein the electromechanical piston control element electrohydraulically actuates the braking-force actuator via the first hydraulic line by the piezoelectric element moving the pump piston in accordance with control from the piezoelectric amplifier; and wherein the hydraulic line is configured for bidirectional flow of a brake fluid, where the first hydraulic line is configured such that the brake fluid flows in a first direction through the hydraulic line when actuating the braking-force actuator, and the brake fluid flows in a second direction through the first hydraulic line when releasing the braking-force actuator.