Vehicle Parking Brake Control Unit Redundancy for Rolling Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle parking brake systems lack reliable automatic generation of braking force to prevent unintentional rolling away when the vehicle is stationary, especially in cases of component failure or disrupted communication between control units.
Innovation Solution
A method utilizing at least two control units and one electric brake motor in the vehicle parking brake system, where if one control unit fails, the second unit automatically activates to generate braking force when the vehicle is stationary or moving at low speed, ensuring the vehicle remains secured without driver intervention, using sensors and parameters like ignition status and seat occupancy to determine the vehicle's state.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single control unit is used in the parking brake system, then the device complexity is reduced, but the reliability decreases due to potential component failure or communication disruption
Solution Approach 1:
The control system is segmented into multiple independent control units (first control unit and second control unit), each capable of independently controlling the brake motor. This segmentation allows the system to maintain functionality even if one control unit fails, thereby improving reliability without significantly increasing overall system complexity.
Solution Approach 2:
The system changes the operational parameter from single-control-unit mode to multi-control-unit mode when failure is detected. The control units can operate in different configurations (both units active, or only one unit active depending on failure conditions), allowing the system to adapt to different operational states and maintain reliability.
2Force
If the parking brake is actuated during driving, then the braking force increases, but the vehicle speed control becomes problematic and may cause unintended deceleration
Solution Approach 1:
The system dynamically adjusts its behavior based on vehicle speed conditions. The determination unit evaluates whether the vehicle is stationary or moving at low speed before enabling automatic braking force generation. This dynamic adaptation ensures that the parking brake only generates braking force when appropriate, preventing unintended deceleration during normal driving while maintaining effectiveness when the vehicle is stationary or moving slowly.
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
Ensures reliable automatic generation of braking force to secure the vehicle against rolling away, even in fault conditions, enhancing safety and convenience during parking maneuvers by automatically engaging the parking brake when necessary.
Implementation Method 1
an electric brake motor (13) which acts on a brake piston (16) in order to move the brake piston (16) towards a brake disc (20)
Implementation Method 2
the piston being displaced by the hydraulic brake pressure against the brake disc when the hydraulic vehicle brake is actuated
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a method for generating braking power by actuating at least one electric braking motor (13a, 13b) in a vehicle parking brake comprising two control devices (11, 24), in the event of a failure (40) of a first control device/braking motor unit (11, 13a), braking power is generated (43) automatically via a second control device/braking motor unit (24, 13a or 24, 13b or 11, 13b) if the vehicle speed is lower than a threshold value and/or if a characteristic value in the vehicle (e.g. the ignition status) indicates (41) that the vehicle is at or is about to come to a standstill, but preferably only once a defined time interval (42) has elapsed.