Planetary Brake Booster Coupling for Dual-Motor Redundancy

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing brake assistance systems for electric vehicles require high power and torque from a single motor, and have complex space layout requirements, with limited redundancy for reliability, as they rely on a decoupled mechanism between actuator motors that can fail under stress.

Innovation Solution

A brake assistance system utilizing a planetary row coupling node with a booster motor, simulation motor, and brake master cylinder, where both motors drive the brake master cylinder simultaneously, reducing power requirements and ensuring continued braking functionality if one motor fails, through a planetary gear mechanism and transmission systems that allow for electro-hydraulic decoupling and closed-loop control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single motor drives the brake master cylinder, then the system structure is simple, but the power and torque requirements for the motor are excessively high

Engineering Contradiction:
Improvesystem structureVSAvoidmotor power requirement
Core Design Contradiction:
Device complexityVSPower

Solution Approach 1:

The patent divides the single motor driving function into two separate motors (first motor and second motor) that work together through a differential mechanism. Each motor handles a portion of the braking torque requirement, reducing the power and torque burden on each individual motor while maintaining the overall braking capability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent combines the output of two motors through a differential mechanism to drive the brake master cylinder. The differential mechanism merges the rotational outputs of both motors into a single linear motion output, allowing the system to achieve the required braking force with distributed motor loads.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If two actuator motors are connected in series with a gap, then the system provides redundancy and space for manual operation, but the system length increases and space layout requirements become more complex

Engineering Contradiction:
Improvebraking system redundancyVSAvoidsystem length
Core Design Contradiction:
ReliabilityVSLength of moving object

Solution Approach 1:

The patent nests the first motor and second motor within a compact differential mechanism structure. The motors are arranged concentrically or in close proximity, with their outputs combined through the differential mechanism, significantly reducing the overall system length compared to a series arrangement with gaps.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The differential mechanism acts as an intermediary that directly couples the outputs of the two motors to the brake master cylinder. This eliminates the need for gaps or intermediate mechanical linkages, providing a compact integrated structure while maintaining the redundancy benefits of having two motors.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Device complexity

If one motor always drives the brake master cylinder, then the control is simple, but the other motor cannot contribute to braking and the single motor must handle all power requirements

Engineering Contradiction:
Improvecontrol complexityVSAvoidsingle motor power requirement
Core Design Contradiction:
Device complexityVSPower

Solution Approach 1:

The patent makes both motors functional contributors to the braking process through the differential mechanism. Each motor can independently or simultaneously drive the brake master cylinder, allowing either motor to handle braking tasks and both to share the load, thereby reducing the power requirement for each motor.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The control system monitors the braking requirements and dynamically adjusts the torque distribution between the two motors. The controller receives feedback on braking force requirements and coordinates the motors accordingly, optimizing power distribution while maintaining simple overall control architecture.

Inventive Principle:
Principle #23Feedback

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 configuration reduces the power demand on individual motors, enhances braking reliability by enabling continued operation if one motor fails, and allows for adjustable braking forces through electro-hydraulic decoupling, improving the overall braking performance and safety of electric vehicles.

Implementation Method 1

a planetary gear mechanism, a first transmission mechanism, a second transmission mechanism, and a third transmission mechanism. The brake pedal drives, by using the first transmission mechanism, a ring gear of the planetary gear mechanism to rotate. The booster motor drives, by using the second transmission mechanism, a planet carrier of the planetary gear mechanism to rotate. The simulation motor is connected to a sun gear of the planetary gear mechanism and is configured to drive the sun gear to rotate. The planet carrier drives, by using the third transmission mechanism, the piston rod to move linearly.

Methodology Applied
Scientific EffectPlanetary gear mechanism: Epicyclic Gearing

Implementation Method 2

The planetary row coupling node is configured to convert a torque of the brake pedal, a torque output by the booster motor, and a torque output by the simulation motor into an acting force acting on a piston rod in the brake master cylinder.

Methodology Applied
Scientific EffectMechanical advantage: Mechanical Advantage

Data Source

PatentEP3851348B1Brake boosting system, braking method and electric vehicle
Publication Date: 2024.10.16 YINWANG INTELLIGENT TECHNOLOGIES CO LTD
  • EP3851348B1 patent drawingFigure 1~2
  • EP3851348B1 patent drawingFigure 3a~3b
  • EP3851348B1 patent drawingFigure 4

AI summary

This application provides a brake assistance system, a brake method, and an electric vehicle. The brake assistance system includes a brake pedal, a booster motor, a simulation motor, a planetary row coupling node, and a brake master cylinder. The brake master cylinder is configured to provide a braking force for the vehicle. The brake pedal, the booster motor, and the simulation motor are separately connected to the planetary row coupling node. The planetary row coupling node is configured to convert a torque of the brake pedal, a torque output by the booster motor, and a torque output by the simulation motor into an acting force acting on a piston rod in the brake master cylinder. It can be learned from the foregoing description that, the planetary row coupling node is disposed, so that both the torque output by the simulation motor and the torque output by the booster motor are used as the force for driving the piston rod of the brake master cylinder. This can reduce an output power requirement on a single motor. In addition, when two motors are used to drive the brake master cylinder at the same time, if one motor fails, the other motor can be used for braking, so that reliability of the entire brake assistance system is improved.