Motor Assembly Back-Driving Prevention via Wrap Spring Locking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing motor assemblies in brake systems face challenges with back-driving issues when using high-efficiency mechanisms, as they do not prevent back-driving after the clamping force is created and power is turned OFF, requiring additional features that increase cost, weight, and complexity.
Innovation Solution
A motor assembly with a locking mechanism that prevents back-driving by engaging when power is OFF and disengaging when power is restored, allowing efficient torque transfer in both directions, utilizing a wrap spring locking mechanism that restricts counter-clockwise rotation while allowing clockwise rotation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a high-efficiency mechanism is used to transfer torque from the motor output, then torque transfer efficiency is improved, but the mechanism cannot prevent back-driving of the motor after power is turned OFF
Solution Approach 1:
The patent combines a high-efficiency torque transfer mechanism with a locking mechanism into a single integrated system. The locking mechanism engages with the torque transfer mechanism to prevent back-driving while maintaining high efficiency during powered operation, resolving the contradiction between efficiency and reliability
Solution Approach 2:
The locking mechanism transitions between engaged and disengaged states based on motor operation. During powered operation, the locking mechanism is disengaged to allow efficient torque transfer. When power is turned OFF, the locking mechanism automatically engages to prevent back-driving, providing dynamic adaptation to operational conditions
2Reliability
If a locking mechanism is added to prevent back-driving when using a high-efficiency mechanism, then back-driving prevention is improved, but device complexity increases
Solution Approach 1:
The locking mechanism is designed to automatically engage and disengage based on motor operation without requiring external control systems. The mechanism self-regulates its locking state based on the presence or absence of motor power, reducing the need for additional control components and simplifying the overall system
Solution Approach 2:
The locking mechanism is integrated within the existing motor assembly structure, with locking components nested within the motor housing and torque transfer mechanism. This nested arrangement minimizes additional space requirements and reduces overall system complexity while maintaining back-driving prevention functionality
3Reliability
If additional features are added to prevent back-driving, then back-driving prevention is improved, but system cost increases
Solution Approach 1:
The locking mechanism utilizes changes in operational parameters (motor power state) to trigger locking and unlocking actions. By leveraging existing parameter changes in the system rather than requiring additional sensors or control systems, the solution reduces manufacturing costs while achieving reliable back-driving prevention
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 motor assembly effectively maintains the clamping force after power is OFF and efficiently transfers torque when power is restored, preventing back-driving and reducing system complexity and cost.
Implementation Method 1
a wrap spring locking mechanism that restricts counter-clockwise rotation while allowing clockwise rotation
Data Source
AI summary
An assembly that includes a main housing. A motor is supported in a motor housing that is supported in the main housing. The motor has an output shaft and a locking mechanism. The motor is adapted to generate a first rotational direction torque and a second rotational direction torque. The motor is adapted to transfer the first rotational direction torque and the second rotational direction torque to a destination via the output shaft. The locking mechanism is adapted to prevent the output shaft from back driving in the second rotational direction after the first rotational direction torque has been transferred to the destination. The motor housing is adapted to rotate in the main housing to unlock the locking mechanism so that the second rotational direction torque can be transferred to the destination.