Electro-Hydraulic Braking with Pedal Decoupling for Regenerative Priority

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing vehicle braking systems face inefficiencies, particularly in electric vehicles, due to insufficient boost from mechanical or vacuum-assisted systems, and low energy recovery rates in electric braking systems, which hinder their application and promotion.

Innovation Solution

An electro-hydraulic braking system decouples the brake pedal from the hydraulic mechanism, utilizing a motor as the primary torque provider, with hydraulic braking as compensation when motor capacity is insufficient, enhancing energy recovery by integrating a displacement sensor and power-assisted motor to manage braking forces effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a mechanical vacuum-assisted brake booster is used, then braking response speed increases and braking distance is shortened, but the booster cannot provide sufficient boost in cases of no vacuum or inadequate vacuum

Engineering Contradiction:
Improvebraking response speedVSAvoidboost reliability under vacuum deficiency
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The braking system is segmented into two independent subsystems: a motor-assisted braking subsystem and a traditional hydraulic braking subsystem. The motor-assisted subsystem provides primary braking force through direct motor torque, while the hydraulic subsystem acts as backup or supplement, eliminating dependency on vacuum conditions for the main braking function.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The mechanical vacuum-assisted brake booster is replaced with an electric motor-assisted braking system. The motor directly generates braking torque through electromagnetic conversion, substituting the mechanical vacuum-based boost mechanism and eliminating the need for vacuum sources.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Speed

If a traditional electric braking system with coupled brake pedal and brake cylinder is used, then motor-assisted boost response is quick, but braking energy recovery rate is low

Engineering Contradiction:
Improvebrake response speedVSAvoidbraking energy recovery rate
Core Design Contradiction:
SpeedVSLoss of energy

Solution Approach 1:

The system decouples the brake pedal from the brake cylinder through a motor intermediary. The brake pedal controls the motor, which then applies braking force to the wheel. This segmentation allows the motor to operate as a generator during regenerative braking, capturing energy that would otherwise be lost, while maintaining quick response through electronic control.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system recovers kinetic energy during braking by operating the motor as a generator. Instead of dissipating braking energy as heat through friction alone, the motor converts kinetic energy into electrical energy that can be stored and reused, thereby recovering energy that would otherwise be wasted.

Inventive Principle:
Principle #34Discarding and recovering

3Force

If hydraulic braking is used as primary braking, then sufficient braking force is provided, but energy recovery rate is low and application in electric vehicles is limited

Engineering Contradiction:
Improvebraking forceVSAvoidenergy recovery rate
Core Design Contradiction:
ForceVSLoss of energy

Solution Approach 1:

The traditional primary hydraulic braking system is replaced with a motor-assisted braking system as the primary braking mechanism. The motor provides direct electromagnetic braking force, enabling energy recovery through regenerative braking while maintaining sufficient braking performance. The hydraulic system becomes secondary or supplemental.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 solution increases the proportion of electric braking, improves energy recovery rates, and provides reliable backup braking, while the unique magnetic field arrangement in the displacement sensor enhances accuracy and durability.

Implementation Method 1

The displacement sensor includes a magnetic element and a Hall sensor (8). The Hall sensor (8) is configured to sense a relative displacement of the magnetic element.

Methodology Applied
Scientific EffectHall effect: Hall Effect

Data Source

PatentEP3984842B1Electro-hydraulic braking system and braking method therefor
Publication Date: 2024.06.05 GLOBAL TECH CO LTD
  • EP3984842B1 patent drawingFigure 1~2
  • EP3984842B1 patent drawingFigure 3~4
  • EP3984842B1 patent drawingFigure 5

AI summary

Disclosed is an electro-hydraulic braking system, relating to the field of vehicle braking systems and includes a main casing. A hydraulic unit brake master cylinder is provided in the main casing. An outer end of a piston rod of the brake master cylinder is connected to an output top rod. Another end of the output top rod is provided with an input rod. The input rod is slidably connected in the main casing along only a length direction of the input rod, and another end of the input rod is provided with a push rod that is configured to transmit a brake pedal force. The main casing is further provided therein with a reset member configured to push the push rod away from the brake master cylinder to reset and a displacement sensor configured to sense a displacement of the push rod. The input rod and the output top rod include a spacing state and an abutment state. In the spacing state, a system performs a regenerative brake by a vehicle drive motor torque; and in the abutment state, the system uses the regenerative brake of the vehicle drive motor torque as a primary braking force, and uses a hydraulic braking generated by the output top rod pushing the piston rod of the brake master cylinder as a compensatory braking force. This increases the proportion of electric braking, thereby improving an energy recovery rate.