Angle Grinder Gear Head Guard Locking Under Breakage Loads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gear heads in hand-held power tools, such as angle grinders, face challenges in maintaining the safety guard's locked position during tool breakage, as high forces deform the securing lever, risking mechanical failure and user injury.
Innovation Solution
A securing device with a contact surface is introduced to redirect forces from the safety guard through the securing lever and gear plate, reducing mechanical overload and allowing for effective force absorption, and is designed with a wedge-shaped cross-section and S-shaped configuration for enhanced rigidity and ease of assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the securing lever is used to lock the safety guard on the gear flange, then the safety guard can be rotatably fixedly connected to the gear flange, but the securing lever deforms under high forces during tool breaking, risking mechanical failure
Solution Approach 1:
The securing device is divided into multiple functional elements: a securing lever for locking, a restoring element for automatic return, and a contact surface for force distribution. This segmentation allows each element to be optimized for its specific function, with the contact surface handling high forces and the securing lever maintaining reliable locking.
Solution Approach 2:
The contact surface acts as an intermediary between the safety guard and the securing lever. It distributes and redirects the high forces occurring during tool breaking away from the securing lever, preventing direct force transmission that would cause deformation while maintaining locking reliability.
2Adaptability or versatility
If the safety guard is rotatably fastened to the gear flange for versatile use, then the safety guard can be adjusted to different positions, but the securing lever may be released during tool breaking due to deformation
Solution Approach 1:
The securing device incorporates dynamic elements including a restoring element that automatically returns the securing lever to its locking position after adjustment. This allows the safety guard to be adjusted to different positions for versatile use while ensuring automatic re-locking maintains reliability during tool breaking events.
Solution Approach 2:
The contact surface is positioned to preemptively redirect forces before they can reach the securing lever during tool breaking. This preliminary anti-action prevents the chain reaction of deformation and potential release, maintaining locking stability even when the safety guard is adjusted to various positions.
3Strength
If the securing lever is designed to withstand high forces, then the locking remains secure during tool breaking, but the adjustment of the securing lever is disadvantaged
Solution Approach 1:
The securing device separates the force resistance function (handled by the contact surface and gear plate) from the adjustment function (handled by the securing lever). This allows the securing lever to be easily adjustable for versatile use while the contact surface structure provides the necessary force resistance during tool breaking.
Solution Approach 2:
The contact surface serves as an intermediary that absorbs and redirects high forces away from the securing lever. This mediation allows the securing lever to maintain ease of adjustment for different safety guard positions while the contact surface ensures force resistance during tool breaking events.
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 effectively prevents deformation of the securing lever, ensuring the safety guard remains locked during tool breakage, reducing the risk of injury and allowing for easy replacement of the securing device, while maintaining user-friendly handling.
Implementation Method 1
a second position, in which the safety guard is rotatably with respect to the gear flange, against the force of a restoring element acting in the direction of the first position
Data Source
AI summary
A gear head for a hand-held power tool for machining workpieces, in particular for an angle grinder. The gear head including a gear plate, a housing closable by the gear plate, in which a power take-off is accommodated, which is connectable to a drive of the hand-held power tool, the power take-off including a tool shaft protruding from the gear plate, which is at least partially surrounded by a safety guard fastenable to a gear flange of the housing. A securing lever locks the safety guard on the gear flange, the securing lever being adjustable around a pivot axis between a first position, in which the safety guard is rotatably fixedly connected to the gear flange and a second position, in which the safety guard is rotatable with respect to the gear flange against a force of a restoring element acting in a direction of the first position.