Key Switch Contact Pattern for Diagonal Input Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional key switches fail to accurately detect diagonal direction inputs, especially when a weak pressing force is applied, leading to missed inputs during complex operations in gaming or similar applications.
Innovation Solution
The key switch design incorporates contact patterns with specific land and gap configurations on a print substrate, allowing for precise detection of direction inputs by ensuring conduction even with small contact areas, including a first and second gap separated by reference lines at predetermined angles, enabling secure circuit conduction with weak pressing forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional contact patterns with two electrode patterns are used, then the structure is simple, but diagonal direction inputs cannot be accurately detected when weak pressing force is applied
Solution Approach 1:
The contact pattern is segmented into multiple separate lands (first land, second land, third land, fourth land) instead of using a single continuous electrode pattern. Each land is positioned to detect specific directional inputs, allowing the system to accurately detect diagonal directions by combining signals from multiple lands while maintaining a relatively simple overall structure.
Solution Approach 2:
Different regions of the contact pattern have different functions - the first and second lands detect one direction, while the third and fourth lands detect another direction. This local differentiation enables precise directional detection without requiring a completely complex structure, as each land is optimized for its specific detection purpose.
2Reliability
If the contact area between conductive rubber and fixed contact is small, then the response is faster, but conduction reliability decreases with weak pressing force
Solution Approach 1:
The contact pattern is divided into multiple separate lands that can be independently contacted by the conductive rubber. This segmentation allows the system to maintain small contact areas for fast response while ensuring that at least one land achieves reliable conduction, as the lands are distributed across different positions and orientations.
Solution Approach 2:
The invention changes the geometric parameters of the contact pattern by creating multiple lands with specific positions and orientations rather than using a single large electrode. This parameter change enables the system to optimize both contact area size and conduction reliability simultaneously.
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 enhances the precision of detecting direction inputs, particularly diagonal directions, by ensuring reliable conduction across contact patterns, even with weak pressing forces, thereby improving input detection accuracy.
Implementation Method 1
capable of detecting conduction caused by a contact between any one of the contact patterns and a corresponding one of the conductive portions
Data Source
Figure 1
Figure 2(a)~2(c)
Figure 3(a)~3(f)
AI summary
A key switch comprises: a plurality of conductive portions which are respectively positioned in dispersed directions from a center of a key top; and contact patterns provided on a print substrate, which respectively face the conductive portions. The contact patterns each have, in a conductive portion facing area thereof, at least four separate lands, and the at least four lands include: a first land and a second land which are separated by a first gap provided on a first reference line which extend from a position facing the center of the key top in the direction of the center of the conductive portion facing area; a third land which is separated from the first land by a second gap provided at a position which is distant from the first reference line in one direction; and a fourth land which is separated from the second land by a third gap provided at a position which is distant from the first reference line in another direction.