Surge Protector Braid Layout for High-Current Arc-Free Disconnection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surge protection devices face limitations in allowing high currents due to restricted conductive cross-sections of resilient strips, which restrict the movement of gas discharge tubes away from varistors when thermofusible connections melt, leading to insufficient disconnection and potential arcing.
Innovation Solution
Incorporating a flexible braid with a larger cross-section, made of braided copper strands, which allows for deformation and movement of the gas discharge tube relative to the varistor when the thermofusible connection melts, along with an insulating flap that moves to prevent arcing, ensuring reliable disconnection and high current transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a resilient strip with limited conductive cross-section is used to allow gas discharge tube movement, then the gas discharge tube can move away from the varistor when thermofusible soldering melts, but the maximum currents that can flow through the surge protection device are restricted
Solution Approach 1:
The patent uses a flexible braid instead of a rigid resilient strip. The flexible braid is composed of multiple thin copper wires braided together, providing both flexibility for movement and sufficient cross-sectional area for high current transmission. This resolves the contradiction by allowing the gas discharge tube to move reliably while maintaining high current carrying capacity.
Solution Approach 2:
The flexible braid combines multiple thin copper wires into a composite structure that exhibits both flexibility and high electrical conductivity. The braided configuration provides mechanical flexibility for disconnection movement while the aggregated cross-section of multiple wires maintains high current transmission capability, resolving the contradiction between reliability and power.
2Power
If the conductive cross-section of the resilient strip is increased to allow high currents, then the maximum currents can be increased, but the stiffness becomes too high to allow the gas discharge tube to move away from the varistor when thermofusible soldering melts
Solution Approach 1:
The flexible braid made of braided copper strands provides sufficient cross-sectional area for high current transmission while maintaining low stiffness through its braided structure. This allows the gas discharge tube to move reliably away from the varistor when the thermofusible connection melts, resolving the contradiction between power and reliability.
Solution Approach 2:
The patent changes the physical parameters of the connection element by using a braided structure with multiple thin wires instead of a solid strip. This structural parameter change maintains electrical conductivity while reducing mechanical stiffness, enabling both high current transmission and reliable disconnection movement.
3Stability of the object's composition
If a rigid connection structure is used to ensure stable electrical connection, then the electrical connection stability is improved, but the gas discharge tube cannot move away from the varistor when thermofusible connection melts leading to potential arcing
Solution Approach 1:
The flexible braid provides a stable electrical connection during normal operation while allowing movement when needed. The braided structure maintains electrical contact stability through its flexibility and conformability, yet enables disconnection movement to prevent arcing, resolving the contradiction between connection stability and arcing prevention.
Solution Approach 2:
The connection structure transitions from a static rigid connection to a dynamic flexible connection that can adapt its state. The flexible braid maintains stable electrical contact during normal operation but can move to disconnect components when the thermofusible connection melts, preventing arcing while maintaining connection stability during service.
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 flexible braid design enables high current transmission while ensuring complete disconnection of the gas discharge tube from the varistor, preventing arcing and extending the component life, thus providing a more effective surge protection.
Implementation Method 1
the thermofusible connection which is capable of changing, when said thermofusible connection is subjected to a temperature exceeding a threshold, from a connected state to a disconnected state
Implementation Method 2
said flexible braid being able to deform so as to allow the gas discharge tube to move away from the first varistor
Implementation Method 3
an insulating flap which is configured to move, when the thermofusible connection passes from the connected state to the disconnected state, from an original position to a cut-off position in which said insulating flap is interposed between the second varistor electrode and the first discharge tube electrode
Implementation Method 4
said flexible braid being able to deform so as to allow the gas discharge tube to move away from the first varistor... offering an excellent compromise between a large cross-section allowing high currents to be transmitted
Data Source
AI summary
A surge protection device has a first connection terminal and a second connection terminal. A first set of protection components having a first varistor and a gas discharge tube are connected to each other by a thermofusible connection with a first arc-breaking device having an insulating flap configured to move when the thermofusible connection changes from a connected state to a disconnected state. The first set of protection components has a flexible braid that is welded to the gas discharge tube and electrically connected to a connection piece that is electrically connected to the second connection terminal that has a flexible braid and capable of being deforming in order to allow the gas discharge tube to move away from the first varistor.