PCB Coil Spring Assembly With Removable Elastic Slot Fitting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for mounting a coil spring to a printed circuit board are difficult to execute, time-consuming, and require additional components, making them expensive and complex, with the soldered spring being non-removable.

Innovation Solution

A removable assembly where a coil spring with an elastically deformable fitting portion is inserted into a slot on the printed circuit board, eliminating the need for additional components and allowing for simple, quick assembly and disassembly without tools.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the spring is joined to the circuit board by soldering, then the connection is strong and reliable, but the execution is difficult and time-consuming, and the spring cannot be removed

Engineering Contradiction:
Improveconnection reliabilityVSAvoidassembly speed
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent replaces the soldering process (thermal/chemical joining) with a mechanical insertion system. The fitting portion with elastic deformation capability allows the spring to be mechanically secured to the circuit board through a slot, eliminating the need for soldering while enabling both strong connection and easy removal.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The fitting portion is designed with elastic deformation properties, allowing it to dynamically adapt during insertion and removal. The elastic material deforms to pass through the slot and then returns to its original shape to secure the spring, providing both strong mechanical bonding and easy disassembly.

Inventive Principle:
Principle #15Dynamics

2Reliability

If additional fixing members are used to mount the spring, then the spring can be securely joined to the circuit board, but the device becomes more expensive and complex

Engineering Contradiction:
Improveconnection reliabilityVSAvoidnumber of components
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the spring and its mounting function into a single integrated component. The fitting portion is formed as an integral part of the spring itself, eliminating the need for separate fixing members, clips, or additional mounting hardware while maintaining secure attachment to the circuit board.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The spring serves multiple functions simultaneously: it provides its primary mechanical function (elastic operation between key and circuit board) and also serves as its own mounting mechanism through the fitting portion. This multi-functionality eliminates the need for dedicated fixing members and reduces overall component count.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Ease of manufacture

If the spring is designed to be removable without tools, then the assembly is easy to manufacture and maintain, but the connection strength may be reduced

Engineering Contradiction:
Improveassembly easeVSAvoidconnection strength
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent changes the physical state of the fitting portion material through elastic deformation during the insertion process. The material temporarily deforms to pass through the slot, then returns to its original shape to create a secure mechanical lock, providing both easy assembly and strong connection without requiring tools.

Inventive Principle:
Principle #35Parameter changes

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 provides a compact, inexpensive, and easy-to-manufacture assembly that is both removable and electrically connected, enabling efficient integration with capacitive keys and other components for visual feedback.

Implementation Method 1

a fitting portion (12) formed by said wire (6) and configured for being inserted, with said fitting portion (12) becoming elastically deformed, into a slot (14) of said printed circuit board (2)

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3358746B1Assembly comprising a printed circuit board and a coil spring
Publication Date: 2022.08.31 BITRON SPA
  • EP3358746B1 patent drawingFigure 1~2
  • EP3358746B1 patent drawingFigure 3~4

AI summary

An assembly comprising: a printed circuit board (2), and a coil spring (4) developing along a longitudinal axis (x-x) and consisting of a wire (6) that defines a spring body (8) having an inner cavity (10). At a first end of the spring (4), the wire (6) forms a fitting portion (12) that, by becoming elastically deformed, is adapted for fitting into an aperture (14) of the printed circuit board (2), so as to removably secure the spring (4) to the printed circuit board (2).