Parking Brake Control During Speed Signal Failure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing motor vehicle parking brake systems face instability when a speed signal fails, leading to potential wheel locking and compromised driving stability during braking from high speeds or downhill driving, as they abruptly apply the parking brake, assuming the vehicle has come to a standstill.
Innovation Solution
A method for controlling an electrically actuable parking brake that continuously closes the brake until a maximum closing force is reached, maintaining this force if the speed signal is absent, ensuring stable braking and preventing wheel locking, with the option to release the brake when a driver signal is detected, using a combination of wheel speed signals and driver-generated electrical signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the parking brake is abruptly applied when speed signal fails, then the vehicle can be brought to standstill, but wheel locking occurs and driving stability is compromised
Solution Approach 1:
The patent applies dynamic control by continuously monitoring wheel speed signals and adjusting the parking brake application force in real-time. When motion is detected, the brake is applied progressively rather than abruptly, and can be modulated or released if wheel locking is detected, thereby maintaining driving stability while ensuring the vehicle eventually stops
Solution Approach 2:
The system uses feedback from wheel speed signals to continuously monitor vehicle motion status. When a speed signal fails, the control device detects this through the absence of expected speed signal changes and uses this feedback information to adjust parking brake application, preventing abrupt full application that would cause wheel locking while still ensuring reliable braking
2Reliability
If the parking brake is applied in a partially closed state and then suddenly fully applied after predetermined time, then the vehicle is brought to standstill, but wheel locking occurs during high speed braking or downhill driving
Solution Approach 1:
The system performs preliminary action by applying the parking brake in a controlled manner before full stopping is achieved. Rather than waiting for a predetermined time and then suddenly applying full brake force, the system progressively applies brake force while monitoring wheel speed, preparing the braking system for safe operation while preventing harmful wheel locking
Solution Approach 2:
The patent changes the parameter of brake application force from a fixed abrupt application to a dynamically adjustable force level. Based on wheel speed signal analysis, the control device modifies the closing force parameter to prevent wheel locking during high-speed or downhill conditions, transitioning from partial to full closure based on actual vehicle state rather than fixed time intervals
3Stability of the object's composition
If the parking brake is continuously closed until maximum closing force is reached, then driving stability is maintained, but the driver loses control over brake engagement
Solution Approach 1:
The system applies self-service by automatically monitoring its own operational state through speed signal feedback and autonomously adjusting parking brake application when speed signal fails. The control device detects the failure condition and manages the braking process without requiring continuous driver input, maintaining stability while preserving driver ability to override or control the system through the brake operation signal
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a procedure for controlling an electrically actuatable parking brake of a motor vehicle in the event of the failure of a first signal indicating the speed of said vehicle. The procedure comprises the following steps: the parking brake is continuously closed as long as a second signal (110) indicating the driver's intention to close the parking brake is detected; and the parking brake is opened if said brake is already partially open as long as no second signal is detected (110).