Pull-Out Guide Latch Cam for Quiet Emergency Opening

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Solution Overview

Problem

Existing opening and closing devices for pull-out runners in furniture, such as drawers, face issues with increased effort and unwanted noise during 'emergency opening' and resetting, which can lead to device damage with repeated use.

Innovation Solution

An opening and closing device with a control cam in the guide housing allows for both pushing and pulling operations without requiring an integrated ejection mechanism, featuring a spring-loaded tension spring for self-closing and a damper to prevent hard impacts during closure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the furniture part is pulled out directly in the extension direction (emergency opening), then the opening speed is increased, but the effort and noise increase and device damage occurs

Engineering Contradiction:
Improveopening speedVSAvoideffort and noise and device damage
Core Design Contradiction:
SpeedVSObject-affected harmful factors

Solution Approach 1:

The control cam acts as an intermediary element that mediates between the driver and the control element. It transforms the pulling motion into a controlled sequence where the control element follows the cam profile, enabling the driver to move to the open position without requiring forceful emergency opening actions

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system transitions from a static latching mechanism to a dynamic control system where the control cam profile dictates the motion sequence. The control element dynamically follows the cam surface, allowing smooth transition between closed and open positions while preventing harmful emergency opening forces

Inventive Principle:
Principle #15Dynamics

2Ease of operation

If the ejection mechanism is used to open the furniture part, then the opening is controlled, but special activation is required and device complexity increases

Engineering Contradiction:
Improvecontrolled openingVSAvoidspecial activation requirement
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The control cam serves multiple functions: it guides the control element during normal operation, enables both pushing and pulling opening methods, and eliminates the need for separate ejection mechanism activation. This multi-functionality reduces device complexity while maintaining controlled opening

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

Solution Approach 2:

Instead of using a separate ejection mechanism that requires special activation, the invention inverts the approach by making the control cam itself the enabling element for both pushing and pulling operations. The control element fixed in the closed position allows the driver to be moved in the extension direction without special activation

Inventive Principle:
Principle #13The other way round (Inversion)

3Force

If the furniture part is pushed in the insertion direction, then the closing force is increased, but hard impacts and damage occur

Engineering Contradiction:
Improveclosing forceVSAvoidhard impacts and damage
Core Design Contradiction:
ForceVSObject-affected harmful factors

Solution Approach 1:

The spring-loaded component provides beforehand cushioning by being pre-compressed between the control cam and the guide housing. This stored elastic energy acts as a buffer during closing operations, absorbing impact forces and preventing hard impacts that could cause damage

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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

Enables smooth and efficient operation by eliminating the need for special activation, reducing effort and noise, and preventing damage through self-closing and damping mechanisms.

Implementation Method 1

a spring-loaded manner. This spring loading is effected in particular by a second energy accumulator designed as a tension spring

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

a damper is arranged on the housing to dampen an insertion movement of the opening and closing device

Methodology Applied
Scientific EffectDamping: Damping

Data Source

PatentEP2266435B1Opening and closing device for an extending guide and extending guide
Publication Date: 2015.02.25 PAUL HETTICH GMBH & CO KG
  • EP2266435B1 patent drawingFigure 1~2
  • EP2266435B1 patent drawingFigure 3~5
  • EP2266435B1 patent drawingFigure 6a~6d

AI summary

The device (4) has a discharge mechanism with an actuator (8) that is arranged in a guide housing (6) along a guide (9) and fixed in open and close positions. The discharge mechanism includes a latch mechanism with a cam and a control element for fixing the actuator in the close position. The cam is formed at a component that is arranged in a guide housing (6) in displacing direction of a pull-out guide i.e. drawer (1), and is arranged into the guide housing in pull direction by a control element that is fixed in the closing position.