External Reaction Fastener Tool Reducing Side Load Strain
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Solution Overview
Problem
Conventional methods for tightening inaccessible threaded fasteners in industrial applications, such as those on the Komatsu 980 Mining Truck, impose excessive strain and side load due to the distance and angle of reaction points, leading to tool failures and instability.
Innovation Solution
An apparatus with a drive extension assembly, reaction assembly, and socket assembly that uses an external reaction member to hold onto two or four adjacent studs, distributing reaction forces more efficiently through an extended drive ball and socket joint, allowing for various fastener angles and obstructions, and is lightweight and user-friendly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a reaction fixture with drive shaft extension is used to reach inaccessible fasteners, then the fasteners can be tightened, but excessive strain and side load are imposed on the system due to the distance and angle of reaction points
Solution Approach 1:
The reaction member acts as an intermediary element that transfers the reaction force from the torque tool to the studs. By positioning the reaction member adjacent to the fastener and distributing the reaction force through multiple studs, it mediates between the torque tool and the fastener, eliminating excessive strain and side load while maintaining accessibility to inaccessible fasteners.
2Ease of operation
If reaction points are positioned far from the fastener, then the tool can reach the fastener, but the distance H creates excessive strain and side load on the drive shaft extension and internal tool gearing
Solution Approach 1:
The reaction force distribution is localized to the immediate area of the fastener being serviced. The reaction member contacts only the studs adjacent to the target fastener, concentrating the reaction force locally rather than distributing it over a long distance. This local quality approach minimizes the moment arm and reduces side load on the drive shaft extension and internal gearing.
3Ease of operation
If a cross-shaped reaction fixture is used, then inaccessible fasteners can be reached, but the fixture creates twisting and tends to creep or crawl off the reaction points
Solution Approach 1:
The reaction member is segmented to contact individual studs separately rather than using a monolithic cross-shaped fixture. This segmentation allows each contact point to be independently optimized for stability, preventing the twisting and creeping behavior observed with rigid cross-shaped fixtures. The reaction member can be positioned precisely against each stud to maximize stability.
4Force
If an external reaction member is used to hold onto adjacent studs, then reaction forces are distributed more efficiently, but the device complexity increases
Solution Approach 1:
The reaction member is designed as a universal component that can engage with multiple different stud configurations and positions. Rather than requiring a custom-designed complex fixture for each specific fastener location, the universal reaction member can adapt to various stud arrangements, simplifying the overall device structure while maintaining efficient reaction force distribution across different applications.
Data Source
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AI summary
This application discloses an apparatus 100 for use with an electrically, hydraulically and/or pneumatically driven torque tool for tightening or loosening inaccessible threaded fasteners including a drive extension assembly 110, a reaction assembly 120 and a socket assembly 130. Advantageously the present invention uses an external reaction member which holds on to two (2) or four (4) adjacent studs while turning a fastener with an extended drive ball and socket joint connection. It more efficiently distributes/reduces the side loads and system strains from the reaction forces on the bolts by bringing the reaction point much closer to the fastener being turned. It allows for a plurality of fastener approach angles and is adaptable to a plurality of fastener obstructions. It's relatively lightweight, easy to maneuver from fastener to fastener and overall user friendly.