Brake Actuator Stopper Mechanism for Excessive Release Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electromechanical brake systems face issues with the stuck phenomenon due to excessive release, which can lead to maintenance challenges when position control of the motor fails.
Innovation Solution
An actuator with a stopper mechanism that uses a stopper protrusion and a stopper groove to prevent rotation of the first gear, allowing the footer to move linearly without causing a stuck phenomenon, and a controller that uses the detected stop position as a reference for motor control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the brake pad is allowed to retract freely during brake release, then the brake system operates smoothly, but the brake pad may retract excessively and contact the screw shaft or footer causing a stuck phenomenon
Solution Approach 1:
The stopper protrusion and stopper groove are designed to engage before excessive retraction can occur. The stopper protrusion on the first gear enters the stopper groove in the footer at a predetermined position, creating a preliminary constraint that prevents the brake pad from retracting too far and contacting the screw shaft, thus preventing the stuck phenomenon before it can occur.
Solution Approach 2:
The controller is configured to identify the stop position where the stopper protrusion engages the stopper groove, and use this position as a reference point for controlling motor rotation. This preliminary identification of the stop position allows the controller to maintain proper brake pad clearance and prevent excessive retraction in subsequent braking operations.
2Reliability
If the controller maintains position control to prevent excessive retraction, then the stuck phenomenon is prevented, but the system becomes dependent on controller accuracy and may fail if position control fails
Solution Approach 1:
The braking function is segmented into two independent systems: a passive mechanical stopper system (stopper protrusion and stopper groove) that provides physical prevention of excessive retraction, and an active controller system that uses the stop position as a reference for precise positioning. This segmentation ensures that if the controller fails, the mechanical stopper still prevents the stuck phenomenon.
Solution Approach 2:
The stopper mechanism is a self-contained mechanical system that automatically engages when the brake pad reaches the correct retraction position, without requiring active control signals or power supply. The stopper protrusion and stopper groove work together passively to limit retraction, making the system self-regulating and independent of controller functionality.
3Length of moving object
If the stopper protrusion is positioned close to the axis, then the footer can move further linearly, but the stopper protrusion may not effectively prevent rotation of the first gear
Solution Approach 1:
The stopper protrusion is positioned at a specific radial distance from the axis of the first gear, and the stopper groove is positioned at a corresponding radial distance in the footer. These parameters are carefully selected to ensure that when the footer moves linearly by the required amount, the stopper protrusion engages the stopper groove at the correct moment to prevent further rotation of the first gear, optimizing both the linear movement distance and the rotation prevention effectiveness.
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
The actuator effectively prevents the stuck phenomenon during brake release and improves motor control stability by using the stop position as a reference, reducing the need for vehicle maintenance.
Implementation Method 1
a second gear connected to the first gear on a same axis as the first gear by a ball screw method, and configured to covert a rotary motion of the first gear into a linear motion
Data Source
AI summary
An actuator may include: a first gear configured to rotate by a motor; a second gear operably connected to the first gear and configured to convert a rotary movement of the first gear into a linear movement; and a footer configured to move linearly together with the second gear to move a back plate of a brake pad. A stopper protrusion may be provided at one end portion of the first gear, the footer may have a stopper groove having a shape of a substantially circular arc or a partial circle such that the stopper protrusion rotating together with the first gear can be inserted in the stopper groove, and as the footer becomes closer to the one end portion of the first gear, the stopper protrusion may be inserted into the stopper groove to prevent the first gear from rotating.