Electromechanical Parking Brake Release with Adaptive Command Timing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electromechanical parking brake systems in vehicles release brakes using a fixed electrical command duration, which is often excessive and uncomfortable for the driver, and do not accurately account for the brake's initial state, temperature, and hydraulic pressure, leading to imprecise brake release.

Innovation Solution

A control unit with temperature and hydraulic pressure probes measures these parameters continuously, adjusting the electrical command duration based on stabilization of the electric current intensity, ensuring precise brake release by adding a safety stroke to account for the brake's state.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a fixed electrical command duration is used to release the brake, then the brake release is simple to control, but the release time is excessive and uncomfortable for the driver

Engineering Contradiction:
Improvebrake release controlVSAvoidbrake release time
Core Design Contradiction:
Ease of operationVSDuration of action of moving object

Solution Approach 1:

The patent applies dynamics by transitioning from a fixed, static command duration to a dynamic, adaptive command duration that adjusts in real-time based on measured brake parameters (temperature, hydraulic pressure, electric current). The control unit continuously monitors these parameters and modifies the electrical command duration accordingly, allowing the system to optimize brake release time for each specific operating condition rather than using a predetermined fixed duration.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent implements feedback by using sensors to continuously measure brake temperature, hydraulic pressure, and electric current intensity, then feeding this information back to the control unit. The control unit processes this feedback and adjusts the electrical command duration to achieve complete brake release. This closed-loop feedback mechanism ensures the brake is fully released under varying conditions without requiring excessive fixed time.

Inventive Principle:
Principle #23Feedback

2Device complexity

If a fixed electrical command duration is used to release the brake, then the control system is simple, but the release precision does not account for brake state, temperature, and hydraulic pressure

Engineering Contradiction:
Improvecontrol system complexityVSAvoidbrake release precision
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent implements feedback by using sensors to continuously measure brake temperature, hydraulic pressure, and electric current intensity, then feeding this information back to the control unit. The control unit processes this feedback and adjusts the electrical command duration to achieve complete brake release. This closed-loop feedback mechanism ensures the brake is fully released under varying conditions without requiring excessive fixed time.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent applies parameter changes by adjusting the electrical command duration based on variations in brake operating parameters such as temperature, hydraulic pressure, and electric current intensity. Rather than maintaining a constant command duration, the system dynamically changes the command parameters to match the actual brake state, thereby achieving precise release control across different operating conditions.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If the electrical command duration is extended to ensure complete brake release, then brake release reliability is improved, but energy consumption increases

Engineering Contradiction:
Improvebrake release reliabilityVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent implements feedback by using sensors to continuously measure brake temperature, hydraulic pressure, and electric current intensity, then feeding this information back to the control unit. The control unit processes this feedback and adjusts the electrical command duration to achieve complete brake release. This closed-loop feedback mechanism ensures the brake is fully released under varying conditions without requiring excessive fixed time.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent applies parameter changes by adjusting the electrical command duration based on variations in brake operating parameters such as temperature, hydraulic pressure, and electric current intensity. Rather than maintaining a constant command duration, the system dynamically changes the command parameters to match the actual brake state, thereby achieving precise release control across different operating conditions.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method reduces release time by approximately a third, conserves energy, and ensures safe, comfortable brake operation, allowing the brake to function effectively as both a parking and emergency brake.

Implementation Method 1

a temperature probe continuously making measurements, respectively, of a temperature present in the brake

Methodology Applied
Scientific EffectTemperature measurement:

Implementation Method 2

a hydraulic pressure probe continuously making measurements, respectively, of a temperature and a hydraulic pressure representative of a temperature and a hydraulic pressure present in the brake

Methodology Applied
Scientific EffectPressure measurement:

Implementation Method 3

an electric motor for moving the actuator

Methodology Applied
Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Data Source

PatentEP4366991B1Device for quickly releasing an electro-mechanical parking brake
Publication Date: 2025.07.30 HITACHI ASTEMO FRANCE
  • EP4366991B1 patent drawingFigure 1~2
  • EP4366991B1 patent drawingFigure 3~4
  • EP4366991B1 patent drawingFigure 5~6

AI summary

The releases of an electromechanical parking brake are controlled by measuring the change in the intensity (I) of the electrical current provided to the control motor, or a function derived from this intensity, and by extending the release of the brake only for a determined duration (Δt) after stabilization of this intensity, in order not to unnecessarily increase the idle travel of the brake actuator nor to extend the duration of the control. The determined duration (Δt) also depends on the temperature and on the hydraulic pressure in the brake.