Quiet Lock Mechanism Using Preliminary Spring Action

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Solution Overview

Problem

Existing locks with rotary latches and pawls often produce noise due to spring force acting on components until they reach their end positions, and there is a need to ensure reliable and quiet operation by minimizing spring force in the end position.

Innovation Solution

A lock design where a spring pivots a pivotable component from an initial to an end position, with no spring force acting on it in the end position, using a stop to prevent further spring loading, allowing the component to settle into place with minimal additional rotation, reducing noise and opening forces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If spring force acts on the pivotable component until it reaches the end position, then the component is reliably moved into position, but noise is generated during the pivoting process

Engineering Contradiction:
Improvereliable operationVSAvoidnoise
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The spring is designed to exert its pivoting action on the component before the component reaches the end position. A stop element prevents the spring from loading the component in the end position, so the component is moved into position by the spring's preliminary action and then settles quietly without continuous spring force application.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If spring force continuously acts on the pivotable component, then the component remains prestressed for reliable positioning, but opening forces increase when moving out of latching positions

Engineering Contradiction:
Improvepositioning reliabilityVSAvoidopening force
Core Design Contradiction:
ReliabilityVSForce

Solution Approach 1:

The spring applies its prestressing force to move the component into the latching position reliably, but a stop element prevents the spring from continuing to load the component once the end position is reached. This eliminates continuous spring force in the latched state, reducing the opening force required to move the component out of its latching position.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If the spring is strongly prestressed to ensure reliable pivoting, then the component reaches its end position reliably, but noise and opening forces increase

Engineering Contradiction:
Improveend position achievementVSAvoidnoise
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The spring can be strongly prestressed to ensure reliable pivoting action, but a stop element is introduced that prevents the spring from loading the component in the end position. The stop ensures the spring's action is limited to the pivoting phase, allowing strong prestressing during movement while eliminating continuous force application that causes noise.

Inventive Principle:
Principle #10Preliminary action

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

Significantly reduces noise and ensures reliable operation by eliminating spring force in the end position, allowing components like pawls and blocking levers to engage quietly and efficiently, with reduced opening forces required to move out of latching positions.

Implementation Method 1

a spring (23) is provided with which a pivotable component (6, 8) of the lock can be pivoted by spring force of the spring (23) from an initial position toward an end position

Methodology Applied
Scientific EffectSpring force: Spring

Data Source

PatentEP2675976B1Lock for a flap or door
Publication Date: 2015.01.21 KIEKERT AG
  • EP2675976B1 patent drawingFigure 1
  • EP2675976B1 patent drawingFigure 2
  • EP2675976B1 patent drawingFigure 3

AI summary

The invention relates to a lock for a door or flap, with a locking mechanism consisting of a rotary latch (4) and a pawl (6), and at least one spring (23) which is capable of pivoting a pivotable component of the lock from a starting position in the direction of an end position by means of spring force. In the end position, the pivotable component is not subjected to a spring force of the spring (23). In particular, operating noises can thus be kept low.