Self-Locking Ring Gearbox for Non-Backdrivable Load Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gear systems face challenges in providing precise, safe, and repeatable mechanical movements, particularly in machinery that requires stopping and moving to known positions, while also addressing noise, vibration, and maintenance issues, especially in applications like theatrical performances and overhead lifting machinery.
Innovation Solution
A self-lubricating, non-backdrivable gearbox system with a ring gear configuration, incorporating planet locking gears and noise-dampening pressure angles, which allows forward and reverse direction driving but prevents back-driving, integrated with a winch/drum system for secure load handling and reduced maintenance needs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a conventional gear system is used to enable bidirectional rotation, then the device can move in both directions, but it allows backdriving which compromises safety and positioning precision
Solution Approach 1:
The patent inverts the conventional gear tooth geometry by using negative pressure angles instead of positive pressure angles. This inversion creates a self-locking mechanism where the gear teeth physically prevent backdriving while still allowing controlled bidirectional rotation through the input shaft, thus maintaining operational flexibility while ensuring safety and positioning precision.
Solution Approach 2:
The patent converts the typically harmful effect of friction and tooth engagement into a beneficial self-locking mechanism. The negative pressure angle gear teeth create intentional friction and mechanical interference that prevents backdriving, transforming what is normally considered a loss (friction) into a useful feature (self-locking capability) that enhances safety and positioning accuracy.
2Reliability
If traditional gear systems are used to achieve self-locking, then non-backdrivable functionality is obtained, but the system requires friction brakes and worm drive gearboxes which increase complexity
Solution Approach 1:
The patent merges the self-locking function directly into the gear tooth geometry itself, eliminating the need for separate friction brakes and worm drive mechanisms. The negative pressure angle gear teeth inherently provide self-locking capability, combining multiple functions (power transmission, bidirectional rotation, and self-locking) into a single integrated gear system, thereby reducing overall device complexity.
Solution Approach 2:
The patent extracts and eliminates unnecessary components (friction brakes, worm drive gearboxes) from the system by incorporating self-locking capability directly into the spur gear design. This extraction simplifies the system structure while maintaining the essential self-locking function, reducing both mechanical complexity and maintenance requirements.
3Productivity
If standard gear teeth are used for power transmission, then efficient motion transfer is achieved, but vibration and noise issues arise that are unacceptable in certain settings
Solution Approach 1:
The patent applies a specific local quality modification to the gear teeth by using negative pressure angles instead of standard positive pressure angles. This localized geometric change at the tooth interface modifies the engagement characteristics to reduce impact and vibration while maintaining efficient power transmission, thereby eliminating noise issues in sensitive environments without sacrificing productivity.
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 solution enables precise, safe, and repeatable mechanical movements with reduced noise and vibration, improved maintenance efficiency, and compact assembly, suitable for various applications including theatrical performances and overhead lifting machinery.
Implementation Method 1
self-lubricating gear system
Implementation Method 2
internal self-lubrication of the gearbox through a volume of lubricant
Implementation Method 3
noise-dampening pressure angles
Data Source
AI summary
The present invention is directed to a self-locking non-backdrivable gear system. The gear system may comprise a primary motor input and gear box. The primary motor input is for rotation of the gearbox about the axis of a drive shaft. The gearbox may comprise an input ring gear, one or more locking gears, fixed gear, and output gear. In operation, rotation of the primary motor input causes rotation of the ring gear which causes rotation of the locking gear which causes rotation of the output gear which causes rotation of the drive shaft. However, in the absence of rotation of the ring gear, a rotational force applied to the output gear causes the gear teeth on the fixed and output gears to lock the gear in place.