Relay Spring Self-Locking Structure for Small Press-Fit Terminals

Solution Overview

Problem

Small relays with a rated load capacity of approximately 8 to 10 A face challenges in securing sufficient press-fitting strength due to their small size, leading to issues like insufficient press-fitting strength and increased manufacturing costs.

Innovation Solution

The relay design incorporates a locked part on the spring that utilizes the resilience of the spring to lock onto the base, and a base with a lock part to secure the locked part, allowing for self-locking during the insertion process without the need for temporary bonding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the springs are made thinner to maintain resilience, then the relay size is reduced, but the press-fitting strength becomes insufficient

Engineering Contradiction:

Improverelay sizeVSAvoidpress-fitting strength

Core Design Contradiction:

Volume of moving objectVSStrength

Solution Approach 1:

The spring is divided into functionally distinct sections: a thin spring portion for maintaining resilience and a thicker terminal portion for ensuring press-fitting strength. This segmentation allows each part to optimize its thickness for its specific function, resolving the contradiction between small size and sufficient press-fitting strength.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the spring have different local properties - the spring portion is thin for resilience while the terminal portion is thick for press-fitting strength. This local differentiation of quality allows the spring to simultaneously achieve both small overall size and adequate press-fitting strength at the insertion point.

Inventive Principle:

Principle #3Local quality

2Strength

If the springs are made thicker to ensure press-fitting strength, then the press-fitting strength is improved, but the relay size increases

Engineering Contradiction:

Improvepress-fitting strengthVSAvoidrelay size

Core Design Contradiction:

StrengthVSVolume of moving object

Solution Approach 1:

The spring is divided into functionally distinct sections: a thin spring portion for maintaining resilience and a thicker terminal portion for ensuring press-fitting strength. This segmentation allows each part to optimize its thickness for its specific function, resolving the contradiction between small size and sufficient press-fitting strength.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the spring have different local properties - the spring portion is thin for resilience while the terminal portion is thick for press-fitting strength. This local differentiation of quality allows the spring to simultaneously achieve both small overall size and adequate press-fitting strength at the insertion point.

Inventive Principle:

Principle #3Local quality

3Reliability

If temporary bonding is applied to secure springs, then the reliability is improved, but the manufacturing cost and process complexity increase

Engineering Contradiction:

Improvespring retention reliabilityVSAvoidmanufacturing process simplicity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The spring structure is designed to be self-locking through its own resilience. The locked part of the spring automatically engages with the base during insertion without requiring external bonding agents or additional securing processes. This self-service mechanism eliminates temporary bonding steps while ensuring reliable spring retention.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The chemical bonding mechanism (temporary bonding agents) is replaced with a mechanical self-locking mechanism based on spring resilience. The spring's elastic deformation and recovery provide the locking force, substituting chemical processes with a purely mechanical solution that is simpler and more reliable.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 solution reduces the risk of spring disengagement, decreases manufacturing costs by eliminating the need for temporary bonding and drying processes, and enhances the reliability of the relay by ensuring consistent press-fitting strength.

Implementation Method 1

at least one of the plurality of springs has a locked part which is locked on the base using resilience of the spring

Methodology Applied

Scientific EffectResilience: Elasticity

Data Source

PatentUS12322564B2Relay

Publication Date: 2025.06.03 FCL COMPONENTS LTD

AI summary

A relay includes an electromagnet, a plurality of springs having contacts which open and close in accordance with operation of the electromagnet and terminals, and a base which supports the springs, wherein at least one of the plurality of springs has a locked part which is locked on the base using resilience of the spring, and the base has a lock part which locks the locked part.