Flexible Contact Strip for Cable Metallic Shield Connection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current devices for reconstructing or restoring the metallic shield of power cables face challenges such as complex installation, difficulty in uniform contact, inability to meet design ratings, inconsistent contact resistance, and ergonomic concerns with deploying constant force springs, particularly due to varying cable designs and ampacity ratings.
Innovation Solution
A device with a flexible, electrically-conductive contact strip wrapped around the cable's circumference, biased by a clamping device like a constant force spring, ensures uniform and consistent contact, using a cover to prevent water ingress and accommodate different cable designs, and a method involving removal of the environmental jacket to expose the metallic shield for connection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional devices are used to reconstruct the metallic shield, then the cable shield can be connected, but the installation process becomes complex and contact uniformity is difficult to achieve
Solution Approach 1:
The device divides the connection function into separate components: a contact strip for uniform circumferential contact, a clamping device for applying force, and a deployment mechanism. This segmentation allows each component to perform its specific function effectively, achieving reliable contact without complex integrated structures
Solution Approach 2:
Instead of using complex multi-component devices that clamp down on the shield, the invention uses a simple contact strip that wraps around the shield and is biased by a spring. The approach is inverted from conventional clamping methods to a wrapping and biasing method, simplifying installation while maintaining contact uniformity
2Reliability
If conventional clamping devices are used, then the shield can be contacted, but contact resistance becomes inconsistent and changes with temperature
Solution Approach 1:
The clamping device uses a spring mechanism that provides dynamic adjustment capability. As the cable expands and contracts with temperature changes, the spring automatically adjusts the clamping force to maintain consistent contact pressure, preventing contact resistance variations
Solution Approach 2:
The spring constant and initial compression are carefully selected to provide the optimal clamping force across the expected temperature range. This parameter optimization ensures that contact resistance remains consistent despite thermal expansion and contraction of the cable
3Force
If constant force springs are deployed manually, then the contact strip can be biased against the shield, but ergonomic concerns and personal injury risks arise
Solution Approach 1:
A deployment tool or mechanism is introduced as an intermediary to handle the constant force spring during installation. This intermediary allows the installer to control the spring deployment safely without direct hand contact, eliminating ergonomic concerns while still achieving the required clamping force
Solution Approach 2:
The spring is designed to be self-deploying through a simple release mechanism. Once activated, the spring automatically extends and applies the clamping force without requiring the installer to manually tension or position it, making the process safe and easy while maintaining the necessary force
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 simplifies installation, maintains consistent contact resistance across temperature ranges, reduces deformation of polymeric layers, and addresses ergonomic concerns, ensuring the device meets cable design ratings for the full life of the cable.
Implementation Method 1
The clamping device is a constant force spring
Implementation Method 2
a flexible, electrically-conductive contact strip
Data Source
AI summary
A device for electrically connecting a cable metallic shield to another electrical element includes a neutral connection portion and an extended connecting member. The neutral connection portion is a flexible contact strip for electrically connecting to the metallic shield of the cable. The extended connecting member connects to the neutral connection portion and is used to electrically connect to another electrical element. The extended connecting member has a plurality of electrical members disposed over the contact strip. A clamping device biases the contact strip against the metallic shield of the cable. In use, an environmental jacket from the electrical cable is removed to expose the metallic shield of the cable. The contact strip is wrapped around the exposed metallic shield, and the clamping device is then connected to the contact strip. Another end of the extended connecting member is then used to connect to the other electrical element.