Carbon PCB Contact System with Adapted Spring Force
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing contact systems, such as those using tin springs on tin circuit boards or gold springs on nickel/gold printed circuit boards, suffer from issues like fretting corrosion, dust sensitivity, and reduced conductivity, leading to cracking noises, interruptions, and insufficient signal intensities, especially when used with loudspeakers.
Innovation Solution
A contact system utilizing a carbon printed circuit board surface with a spring that has adapted spring force and electrical/electronic means to manage contact resistance, potentially replacing costly gold or nickel/gold surfaces, and incorporating gold springs for optimal performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a tin spring contacts a tin circuit board surface, then the contact system is cost-effective, but it leads to field failures due to fretting corrosion
Solution Approach 1:
The patent replaces expensive gold springs with inexpensive tin springs, accepting that the spring is a consumable component that may wear over time. This resolves the contradiction by using a low-cost material (tin) that sacrifices longevity to achieve cost-effectiveness, while the overall system reliability is maintained through design redundancy and the durability of the carbon contact surface.
Solution Approach 2:
The patent creates a composite contact system combining tin spring material with carbon circuit board surface material. This composite approach allows the tin spring to provide cost-effective elasticity while the carbon surface provides superior wear resistance and fretting corrosion resistance, resolving the contradiction between cost and reliability.
2Reliability
If a gold spring contacts a nickel/gold printed circuit board surface, then the contact system has good conductivity, but it is sensitive to dust
Solution Approach 1:
The patent replaces expensive gold springs with inexpensive tin springs that have sufficient conductivity for the application. The tin spring acts as a sacrificial element that can be replaced if contaminated, resolving the contradiction by using a lower-cost material with adequate electrical properties that tolerates dust exposure better than gold.
Solution Approach 2:
The carbon layer on the circuit board surface acts as an intermediary between the tin spring and the underlying nickel/gold traces. This carbon mediator provides a dust-resistant interface that maintains electrical contact while protecting the precious metal layers from direct exposure to contaminants.
3Object-affected harmful factors
If a carbon layer is used on the mating contact, then the contact system is less sensitive to dust, but it has lower conductivity
Solution Approach 1:
The patent uses a composite contact system where the carbon layer provides dust resistance while the tin spring provides the necessary electrical conductivity. The combination of these two materials with complementary properties resolves the contradiction by allowing each material to fulfill its strength - carbon for contamination resistance and tin for electrical conduction.
Solution Approach 2:
The carbon layer is applied locally only at the contact surface where dust resistance is needed, while the underlying nickel/gold traces maintain high conductivity for signal transmission. This localized application resolves the contradiction by providing dust protection only where required without compromising overall system conductivity.
4Reliability
If gold or nickel/gold surfaces are used for contacting, then the contact system has low contact resistance, but it increases production costs
Solution Approach 1:
The patent replaces expensive gold and nickel/gold contact surfaces with inexpensive tin springs and carbon layers. The tin spring acts as a disposable or replaceable component that provides sufficient electrical contact for the application, resolving the contradiction by using low-cost materials that meet the electrical performance requirements without the high material costs of precious metals.
Solution Approach 2:
The carbon layer serves as an intermediary contact surface that provides adequate electrical conductivity for digital switching signals while being much cheaper than gold or nickel/gold surfaces. This carbon mediator allows the system to achieve acceptable contact resistance at a fraction of the cost of precious metal contacts.
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 contact system achieves significantly improved durability and resistance to dust, with service lives exceeding 1 million friction cycles and stable performance, eliminating cracking noises, while the higher impedance can be easily compensated for, maintaining signal integrity and reducing production costs.
Implementation Method 1
a spring (1) whose contact pressure is adapted to the conditions of the contact system
Implementation Method 2
contact resistance between the spring and the carbon circuit board surface
Data Source
AI summary
The invention relates to a contact system comprising a spring and an accordingly associated printed circuit board surface, with which the spring is in contact. The printed circuit board surface to be contacted is a carbon printed circuit board surface. Increased contact resistance between the spring and the carbon printed circuit board surface, which is associated with the contact system according to the invention, is furthermore compensated for by electric and/or electronic means. The spring that is used is provided with a spring force adapted to the carbon printed circuit surface.