# US 12,759,526 B2 · Control for an electromechanical brake actuator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,526 B2 - Document ID: US12759526B2 - Status: Granted - Kind: B2 - Application number: 18/513,352 - Filed: 2023-11-17 - Published: 2025-05-22 - Granted: 2026-10-13 - Earliest claimed: 2023-11-17 - Assignees: Goodrich Corporation - Applicants: Goodrich Corporation - Inventors: Marc J Georgin; Kaman Thapa Magar; Jake Ferris - Web page: https://patentgrep.com/patent/US12759526B2 ## CPC - B60T 17/22: Devices for monitoring or checking brake systems; Signal devices - B60T 7/12: for automatic initiation; for initiation not subject to will of driver or passenger {(limiting speed of vehicles other than rail vehicles B60K31/00)} - B60T 8/1703: {for aircrafts} - B64C 25/44: Actuating mechanisms - F16D 55/38: mechanically actuated - F16D 65/18: adapted for drawing members together {, e.g. for disc brakes} - F16D 66/00: Arrangements for monitoring working conditions, e.g. wear, temperature - F16D 2066/003: {Position, angle or speed} - F16D 2066/005: {Force, torque, stress or strain} - F16D 2066/006: {without direct measurement of the quantity monitored, e.g. wear or temperature calculated form force and duration of braking} - F16D 2125/40: Screw-and-nut - F16D 2127/02: Release mechanisms - B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES - B64C: AEROPLANES; HELICOPTERS - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES ## Abstract A brake system includes a pressure plate, an end plate, a plurality of rotating discs positioned between the pressure plate and the end plate, an electromechanical brake actuator controller, and an electromechanical brake actuator including a ball screw configured to extend to exert force on the pressure plate, the electromechanical brake actuator operatively coupled to the electromechanical brake actuator controller. Responsive to receiving a command from the electromechanical brake actuator controller, the electromechanical brake actuator is configured to retract the ball screw away from the pressure plate to at least a zero-touch point. ## Claims ### Claim 1 A brake system comprising: a pressure plate; an end plate; a plurality of rotating discs positioned between the pressure plate and the end plate; an electromechanical brake actuator controller; and an electromechanical brake actuator comprising a ball screw configured to extend to exert a force on the pressure plate, the electromechanical brake actuator operatively coupled to the electromechanical brake actuator controller; wherein, responsive to receiving a command from the electromechanical brake actuator controller, the electromechanical brake actuator is configured to retract the ball screw away from the pressure plate to at least one of a first zero-touch point, a second zero-touch point, a third zero-touch point, or a fourth zero-touch point, wherein the brake system further comprises a load cell, wherein the third zero-touch point is determined by: responsive to operating under force control and responsive to an autozero failing to be established for the load cell, determining, by the electromechanical brake actuator controller, a third position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a third predetermined force threshold; and determining, by the electromechanical brake actuator controller, the third zero-touch point by subtracting a third offset from the third position of the ball screw, and wherein the fourth zero-touch point is determined by: responsive to operating under the force control and responsive to the autozero being established for the load cell, determining, by the electromechanical brake actuator controller, a fourth position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a fourth predetermined force threshold; and determining, by the electromechanical brake actuator controller, the fourth zero-touch point by subtracting a fourth offset from the fourth position of the ball screw. ### Claim 2 (depends on 1) The brake system of claim 1, wherein the electromechanical brake actuator is configured to retract the ball screw away from the pressure plate behind the at least one of the first zero-touch point, the second zero-touch point, the third zero-touch point, or the fourth zero-touch point. ### Claim 3 (depends on 1) The brake system of claim 1, wherein the brake system further comprises: a position sensor, wherein the first zero-touch point, the second zero-touch point, the third zero-touch point, and the fourth zero-touch point are determined using the position sensor and wherein the position sensor is at least one of a resolver, tachometer, or Hall sensor. ### Claim 4 (depends on 3) The brake system of claim 3, wherein the brake system further comprises: wherein the first zero-touch point is determined by: responsive to operating under position control and responsive to the autozero failing to be established for the load cell, determining, by the electromechanical brake actuator controller, a first position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a first predetermined force threshold; and determining, by the electromechanical brake actuator controller, the first zero-touch point by subtracting a first offset from the first position of the ball screw. ### Claim 5 (depends on 3) The brake system of claim 3, wherein the brake system further comprises: wherein the second zero-touch point is determined by: responsive to operating under position control and responsive to the autozero being established for the load cell, determining, by the electromechanical brake actuator controller, a second position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a second predetermined force threshold; and determining, by the electromechanical brake actuator controller, the second zero-touch point by subtracting a second offset from the second position of the ball screw. ### Claim 6 An aircraft, comprising: a wheel; and a brake system coupled to the wheel, wherein the brake system comprises: a pressure plate; an end plate; a plurality of rotating discs positioned between the pressure plate and the end plate; an electromechanical brake actuator controller; and an electromechanical brake actuator comprising a ball screw configured to extend to exert a force on the pressure plate, the electromechanical brake actuator operatively coupled to the electromechanical brake actuator controller; wherein, responsive to receiving a command from the electromechanical brake actuator controller, the electromechanical brake actuator is configured to retract away from the pressure plate to at least one of a first zero-touch point, a second zero-touch point, a third zero-touch point, or a fourth zero-touch point, wherein the brake system further comprises a load cell, wherein the third zero-touch point is determined by: responsive to operating under force control and responsive to an autozero failing to be established for the load cell, determining, by the electromechanical brake actuator controller, a third position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a third predetermined force threshold; and determining, by the electromechanical brake actuator controller, the third zero-touch point by subtracting a third offset from the third position of the ball screw, and wherein the fourth zero-touch point is determined by: responsive to operating under the force control and responsive to the autozero being established for the load cell, determining, by the electromechanical brake actuator controller, a fourth position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a fourth predetermined force threshold; and determining, by the electromechanical brake actuator controller, the fourth zero-touch point by subtracting a fourth offset from the fourth position of the ball screw. ### Claim 7 (depends on 6) The aircraft of claim 6, wherein the electromechanical brake actuator is configured to retract away from the pressure plate behind the at least one of the first zero-touch point, the second zero-touch point, the third zero-touch point, or the fourth zero-touch point. ### Claim 8 (depends on 6) The aircraft of claim 6, wherein the brake system further comprises: a position sensor, wherein the first zero-touch point, the second zero-touch point, the third zero-touch point, and the fourth zero-touch point are determined using the position sensor and wherein the position sensor is at least one of a resolver, tachometer, or Hall sensor. ### Claim 9 (depends on 8) The aircraft of claim 8, wherein the brake system further comprises: wherein the first zero-touch point is determined by: responsive to operating under position control and responsive to the autozero failing to be established for the load cell, determining, by the electromechanical brake actuator controller, a first position of the ball screw of the electromechanical brake actuator in response to the force being applied by the electromechanical brake actuator dropping below a first predetermined force threshold; and determining, by the electromechanical brake actuator controller, the first zero-touch point by subtracting a first offset from the first position of the ball screw. ### Claim 10 (depends on 8) The aircraft of claim 8, wherein the brake system further comprises: wherein the second zero-touch point is determined by: responsive to operating under position control and responsive to the autozero being established for the load cell, determining, by the electromechanical brake actuator controller, a second position of the ball screw of the electromechanical brake actuator in response to the force being applied by the electromechanical brake actuator dropping below a second predetermined force threshold; and determining, by the electromechanical brake actuator controller, the second zero-touch point by subtracting a second offset from the second position of the ball screw. ### Claim 11 A method of controlling an electromechanical brake actuator of a brake system comprising: receiving, by an electromechanical brake actuator controller, a command from a brake control unit, wherein the command is to retract a ball screw within the electromechanical brake actuator away from a pressure plate, the ball screw configured to extend to exert a force on the pressure plate; identifying, by the electromechanical brake actuator controller, at least one of a first zero-touch point, a second zero-touch point, a third zero-touch point, or a fourth zero-touch point for the electromechanical brake actuator; and commanding, by the electromechanical brake actuator controller, the electromechanical brake actuator to retract the ball screw away from the pressure plate to the at least one of the first zero-touch point, the second zero-touch point, the third zero-touch point, or the fourth zero-touch point, wherein the third zero-touch point is determined by the method further comprising: responsive to operating under force control and responsive to an autozero failing to be established for a load cell, determining, by the electromechanical brake actuator controller, a third position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a third predetermined force threshold; and determining, by the electromechanical brake actuator controller, the third zero-touch point by subtracting a third offset from the third position of the ball screw, and wherein the fourth zero-touch point is determined by the method further comprising: responsive to operating under the force control and responsive to the autozero being established for the load cell, determining, by the electromechanical brake actuator controller, a fourth position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a fourth predetermined force threshold; and determining, by the electromechanical brake actuator controller, the fourth zero-touch point by subtracting a fourth offset from the fourth position of the ball screw. ### Claim 12 (depends on 11) The method of claim 11, wherein the electromechanical brake actuator is configured to retract the ball screw away from the pressure plate behind the at least one of the first zero-touch point, the second zero-touch point, the third zero-touch point, or the fourth zero-touch point. ### Claim 13 (depends on 11) The method of claim 11, wherein the first zero-touch point is determined by the method further comprising: responsive to operating under position control and responsive to the autozero failing to be established for the load cell, determining, by the electromechanical brake actuator controller, a first position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a first predetermined force threshold; and determining, by the electromechanical brake actuator controller, the first zero-touch point by subtracting a first offset from the first position of the ball screw. ### Claim 14 (depends on 11) The method of claim 11, wherein the second zero-touch point is determined by the method further comprising: responsive to operating under position control and responsive to the autozero being established for the load cell, determining, by the electromechanical brake actuator controller, a second position of the ball screw in response to the force being applied by the electromechanical brake actuator dropping below a second predetermined force threshold; and determining, by the electromechanical brake actuator controller, the second zero-touch point by subtracting a second offset from the second position of the ball screw.