# US 2019/0315322 A1 · Electric brake apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0315322 A1 - Document ID: US20190315322A1 - Status: Published application - Kind: A1 - Application number: 16/313,588 - Filed: 2017-05-26 - Published: 2019-10-17 - Earliest claimed: 2016-06-28 - Assignees: Hitachi Automotive Systems, Ltd. - Applicants: Hitachi Automotive Systems, Ltd. - Inventors: Daisuke GOTO; Takuya USUI - Web page: https://patentgrep.com/patent/US20190315322A1 ## CPC - B60T 8/00: Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force (by changing number of effective brake cylinders in power brake systems B60T17/10) - B60T 8/17: Using electrical or electronic regulation means to control braking {(detecting or indicating faulty operation B60T8/885)} - B60T 7/042: {by electrical means, e.g. using travel or force sensors} - 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 8/171: Detecting parameters used in the regulation; Measuring values used in the regulation - B60T 8/172: Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters {(B60T8/17551 takes precedence)} - B60T 8/4081: {Systems with stroke simulating devices for driver input (B60T8/4077 takes precedence)} - B60T 13/66: Electrical control in fluid-pressure brake systems - B60T 13/662: {characterised by specified functions of the control system components} - B60T 13/74: with electrical assistance or drive - B60T 13/745: {acting on a hydraulic system, e.g. a master cylinder} - B60T 7/22: initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle {, or by means of contactless obstacle detectors mounted on the vehicle} - B60T 2201/06: Hill holder; Start aid systems on inclined road - B60T 2270/10: ABS control systems - B60T 2270/20: ASR control systems - B60T 2270/30: ESP control system - B60T 2270/82: Brake-by-Wire, EHB - 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 ## Abstract Provided is an electric brake apparatus capable of accurately generating a desired braking hydraulic pressure. An ECU moves a power piston to cause a braking hydraulic pressure to be generated in a master cylinder by controlling an electric motor 37 of an electric actuator based on an operation on a brake pedal (an input member position). A characteristic correction processing portion of the ECU corrects, based on an operation amount of the brake pedal, characteristic data indicating a relationship between a hydraulic value transmitted from an ECU via a vehicle data bus and a movement amount of the power piston controlled based on the input member position, and stores it. The ECU controls the electric actuator based on the corrected characteristic data when an automatic brake instruction is input. ## Claims ### Claim 1 An electric brake apparatus comprising: an electric actuator configured to be activated so as to generate a braking hydraulic pressure in a master cylinder of a vehicle; an operation amount detector configured to detect an operation amount of a brake pedal of the vehicle; a piston configured to be moved due to the activation of the electric actuator; a movement amount detector configured to detect a movement amount of the piston; and a controller configured to control the electric actuator to move the piston based on a first braking instruction value based on an operation on the brake pedal or a second braking instruction value input from an inter-apparatus communication network of the vehicle, wherein the controller is configured to: control the electric actuator based on the first braking instruction value to move the piston to thereby generate a braking hydraulic pressure when the first braking instruction value is input; correct, based on the operation amount of the brake pedal, characteristic data indicating a relationship between the braking hydraulic value in the master cylinder input from the inter-apparatus communication network and the movement amount of the piston controlled based on the first braking instruction value, and store the corrected characteristic data while the braking hydraulic pressure is generated; and control the electric actuator based on the corrected characteristic data when the second braking instruction value is input. ### Claim 2 (depends on 1) The electric brake apparatus according to claim 1, wherein the controller is further configured to correct the characteristic data when the operation amount of the brake pedal is increasing. ### Claim 3 (depends on 1) The electric brake apparatus according to claim 1, wherein the controller is further configured to correct the characteristic data when the braking hydraulic value and the movement amount of the piston are increasing. ### Claim 4 (depends on 1) The electric brake apparatus according to claim 1, wherein the master cylinder is configured to supply the braking hydraulic pressure to a wheel cylinder that applies a braking force to the vehicle, and wherein the controller is further configured to prohibit the correction of the characteristic data when a hydraulic pressure supply apparatus provided between the master cylinder and the wheel cylinder functions and a hydraulic pressure in the wheel cylinder is increasing or reducing. ### Claim 5 (depends on 1) The electric brake apparatus according to claim 1, wherein the controller is further configured to calculate the correction of the characteristic data in consideration of a transmission time in the inter-apparatus communication network. ### Claim 6 (depends on 1) The electric brake apparatus according to claim 1, further comprising: an input member connected to the brake pedal; and a reaction disk abutting against the input member and the piston, and configured to distribute a reaction force of the braking hydraulic pressure generated in the master cylinder to the input member and the piston, wherein the controller is further configured to calculate the correction of the characteristic data in consideration of a deformation amount of the reaction disk.