PCB Plug Contact With U-Shaped Legs for Small-Hole Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plug-in contacts face challenges in achieving secure and reversible electrical connections, especially when the material thickness is small, leading to inadequate normal contact force and potential damage to the circuit board, and require complex coating processes.
Innovation Solution
The design features two contact legs with a U-shaped contour formed by bending out of the connection area plane, with spherical contacting areas that are not dependent on the material thickness, allowing for adaptable geometry and easy coating, and a spring-loaded clamping connection for easy conductor connection and disconnection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the contact legs are made with narrow width to fit small contact holes, then the plug-in contact can be inserted into small contact holes, but the normal contact force becomes insufficient and the connection reliability deteriorates
Solution Approach 1:
The contact legs are bent out of the plane of the connection area into a three-dimensional U-shaped configuration. This dimensional change allows the contact legs to engage with the contact hole walls from multiple directions, providing sufficient contact force and reliable electrical connection even when the contact hole diameter is small, thus resolving the contradiction between fitting small holes and maintaining connection reliability
Solution Approach 2:
The contacting areas on the contact legs are designed with spherical or curved surfaces instead of flat planes. This curvature allows for better point contact and stress distribution within the contact hole, enabling reliable electrical connection with small contact holes while maintaining adequate normal contact force
2Manufacturing precision
If the material thickness is reduced to achieve finer pitch, then the manufacturing precision improves, but the normal contact force becomes insufficient
Solution Approach 1:
By bending the contact legs out of the plane into a U-shaped three-dimensional structure, the design compensates for the reduced material thickness. The three-dimensional configuration provides mechanical leverage and engagement that generates sufficient normal contact force even when the flat material thickness is small, thus enabling fine pitch while maintaining adequate contact force
Solution Approach 2:
The design changes the geometric parameters of the contact legs by bending them at specific angles and creating a U-shaped contour. This parameter transformation allows the contact legs to generate sufficient contact force through their bent geometry rather than relying solely on material thickness, enabling fine pitch manufacturing while maintaining adequate normal contact force
3Force
If the contact legs are made resilient to provide sufficient contact force, then the normal contact force improves, but the risk of damaging the circuit board increases
Solution Approach 1:
The U-shaped three-dimensional configuration distributes the contact force across multiple engagement points with the contact hole walls rather than concentrating it at a single point. This dimensional distribution reduces the peak stress on the circuit board while maintaining sufficient overall contact force for reliable electrical connection
Solution Approach 2:
The spherical contacting areas on the resilient contact legs provide point contact that concentrates force efficiently while the curved geometry allows for elastic deformation. This enables the contact legs to be resilient and generate sufficient contact force without creating sharp edges or concentrated stresses that could damage the circuit board
4Ease of manufacture
If the contacting areas are formed on punched edges, then the manufacturing process is simplified, but the coating process becomes complex
Solution Approach 1:
The contacting areas are formed on the outer sides of the contact legs before the bending process, while the contact legs are still in their initial flat or partially formed state. This preliminary formation allows for simpler and more uniform application of conductive coatings or plating, avoiding the complexity of coating pre-formed punched edges after bending
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
This design ensures secure, reversible, and long-lasting electrical connections with sufficient normal contact force, even with low material thickness, and simplifies the coating process by applying it before bending, while allowing multiple insertions without damaging the circuit board.
Implementation Method 1
two contact legs (4, 5) that are resilient relative to one another
Data Source
Figure 1~2
Figure 3~7
Figure 4a~4b
AI summary
The invention relates to a plug contact (1) for electrically contacting a circuit board (2) by means of the insertion of the plug contact (1) into a contact hole (3) of the circuit board (2), which plug contact comprises two contact legs (4, 5), which are resilient relative to each other, a connection region (6), and a connecting region (7), wherein the connecting region (7) connects the two contact legs (4, 5) to one another and to the connection region (6) and wherein the plug contact (1) is stamped from a flat metal material and is bent. The plug contact (1) according to the invention enables secure contacting, even in the case of a small material thickness of the flat material, in that the two contact legs (4, 5) each have a first section (4a, 5a) and a second section (4b, 5b) adjoining the first section in the insertion direction (E) of the plug contact (1), wherein the two contact legs (4, 5) are bent from the plane of the connecting region (7) such that the connecting region (7) and the first regions (4a, 5a) of the two contact legs (4, 5) adjoining the connecting region (7) together form a U-shaped contour, and that a contacting region (4c, 5c) that contacts the contact hole (3) in the inserted state is formed on each of the outer faces of the two sections (4b, 5b) of the two contact legs (4, 5), which outer faces face away from each other.