Vehicle Dashboard Push-Button Switch Misaligned Actuator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing push-button switches in vehicles face challenges in achieving a short stroke length while maintaining operational reliability and acoustic performance, as the minimum stroke is limited by tolerance chains and structural geometry, which affects the perceived quality and functionality.
Innovation Solution
A push-button switch design featuring a misaligned actuator member and pre-loading device, integrated damping member, and a metal dome switch member, which minimizes the tolerance chain and allows for a reduced stroke length of 0.4 mm without compromising acoustic performance, and includes a pre-loading device integrated into the pad for cost reduction and structural simplicity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the stroke of the push-button switch is reduced to improve perceived quality and facilitate operation, then the ease of operation and perceived quality are improved, but the reliability of state change may deteriorate due to tolerance chain limitations
Solution Approach 1:
The pre-loading device is extracted from the tolerance chain by misaligning it with the actuator member. The pre-loading device acts on the cursor base while the actuator member acts on the switch member, creating independent action paths. This extraction eliminates the cumulative tolerance effects that would otherwise limit stroke reduction, allowing the stroke to be minimized for better operability without compromising the reliability of state change.
2Ease of manufacture
If the stroke of the push-button switch is reduced to improve perceived quality, then the perceived quality is improved, but the manufacturing precision requirements increase due to tighter tolerance chains
Solution Approach 1:
By extracting the pre-loading device from the tolerance chain through misalignment, the patent reduces the number of components whose tolerances must accumulate. The misaligned configuration allows the pre-loading device to provide necessary force without being part of the precise alignment requirements between the actuator member and switch member, thereby reducing manufacturing precision requirements while maintaining perceived quality through short stroke.
3Reliability
If the pre-loading device is aligned with the actuator member to ensure proper force application, then the reliability of force application is improved, but the device complexity and weight increase due to the tolerance chain
Solution Approach 1:
The pre-loading device is extracted from the direct alignment path with the actuator member. The misaligned configuration allows the pre-loading device to act on the cursor base independently, providing necessary pre-loading force without requiring precise alignment with the actuator member. This extraction reduces device complexity and weight by eliminating the need for additional alignment features and reducing the cumulative tolerance chain, while maintaining reliability through the independent action path.
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 enables a compact, cost-effective, and acoustically satisfactory push-button switch with a reduced stroke length, enhancing user experience by providing a high-quality tactile feedback and maintaining device reliability.
Implementation Method 1
a pad (4), made of an elastic polymeric material, applied to the inner face (2a) of the substrate (2)
Implementation Method 2
a dome-shaped metal switch member (8), directly housed on the substrate (2) in a seat (21) between the pad (4) and the substrate (2)
Data Source
Figure 1~2
Figure 3~5
Figure 6~7
AI summary
A push-button switch includes: a substrate (2), on which an electric circuit (3) is provided; a cursor (7) movable along an actuation direction (D) with a stroke between a rest position and a pressed position; a pad (4) made of an elastic polymeric material applied to the substrate (2); a pre-loading device (10) configured to provide a pre-loading force to the cursor (7) along the actuation direction (D) toward the rest position; and a dome-shaped metal switch member (8) housed directly on the substrate (2) in a seat (21) between the pad (4) and the substrate (2). The cursor (7) has a base (7a) coupled to the pre-loading device (10) and is provided with an actuator member (20) extending from the base (7a) parallel to the actuation direction (D) and configured to actuate the switch member (8). The actuator member (20) is aligned to the switch member (8) and is misaligned with respect to the pre-loading device (10).