Electronic Parking Brake Locking After Hydraulic Piston Engagement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electronic parking brake systems rely on electrical power or hydraulic assistance to maintain braking force, which can fail in scenarios without power or hydraulic fluid.
Innovation Solution
The system employs a caliper assembly with a piston that is initially moved into engagement with a brake pad using hydraulic pressure, and then locked in place by a parking brake, allowing the hydraulic pressure to be removed while maintaining braking force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hydraulic pressure is continuously applied to maintain braking force, then reliable braking is achieved, but the system requires continuous hydraulic assistance which may fail
Solution Approach 1:
The system pre-pressurizes the hydraulic piston before parking brake engagement to the level needed for maintaining braking force. This preliminary action allows the piston to be locked in place without requiring continuous hydraulic pressure, enabling the system to maintain braking force even when hydraulic assistance is unavailable.
Solution Approach 2:
A lock mechanism acts as an intermediary between the hydraulic piston and the brake pad. This lock holds the piston in its pressurized position, transferring the braking force maintenance function from the hydraulic system to a mechanical locking system, thereby enabling operation without continuous hydraulic assistance.
2Reliability
If electrical power is used to maintain parking brake, then controlled braking is achieved, but the system fails when electrical power is unavailable
Solution Approach 1:
The system uses the existing hydraulic service brake infrastructure to self-pressurize the parking brake piston. Once pressurized, the lock mechanism maintains the braking force passively without requiring continuous electrical power input. The system essentially services itself using the vehicle's normal braking system.
Solution Approach 2:
The patent replaces an electrically-powered parking brake actuator with a hydraulically-pressurized mechanical lock system. This substitution eliminates the need for continuous electrical power while maintaining parking brake functionality, as the mechanical lock holds the hydraulic piston in position.
3Device complexity
If hydraulic pressure is removed after piston engagement, then system simplicity is improved, but braking force cannot be maintained
Solution Approach 1:
The lock mechanism serves as an intermediary that decouples the hydraulic pressure requirement from braking force maintenance. It allows the hydraulic system to be simplified and pressure to be removed, while the lock maintains the piston position and thus the braking force.
Solution Approach 2:
The parking brake function is segmented into two independent components: the hydraulic pressurization system and the mechanical lock system. This segmentation allows the hydraulic system to be simplified or removed while the lock system independently maintains braking force.
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 enables the electronic parking brake to maintain braking force without electrical power or hydraulic assistance, providing reliable parking brake functionality even in power or hydraulic fluid failure scenarios.
Implementation Method 1
moving a piston into engagement with the brake pad by applying hydraulic pressure to the piston
Data Source
AI summary
A method for controlling vehicle braking of a wheel rotor having a brake pad associated therewith includes moving a piston into engagement with the brake pad by applying hydraulic pressure to the piston. The piston is locked in place against the brake pad with a parking brake. The hydraulic pressure is removed from the piston while the parking brake is locked.