Dishwasher Door Lock Hook Mechanism for Low Closing Force

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Dishwasher door closure mechanisms require high closing forces, which can be inconvenient and pose challenges in design, particularly for cost-sensitive household appliances and child safety considerations.

Innovation Solution

A closure mechanism with a spring-mounted locking hook and approach slope, where the locking hook engages with a trough in the closure element, reducing closing force and incorporating a child safety feature with a locking pin that can be manually released for opening, utilizing a tension spring and compression spring for efficient operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional closure mechanism with locking hook and latch is used, then the door can be securely locked, but the closing force required is high

Engineering Contradiction:
Improvelocking reliabilityVSAvoidclosing force
Core Design Contradiction:
ReliabilityVSForce

Solution Approach 1:

The approach slope on the locking hook performs preliminary action by gradually guiding the locking element into engagement position before the final locking occurs. This gradual engagement reduces the peak closing force needed compared to immediate engagement, while still achieving secure locking through the subsequent engagement of the locking hook with the locking element.

Inventive Principle:
Principle #10Preliminary action

2Ease of operation

If a simple closure mechanism is used to reduce closing force, then ease of operation improves, but child safety may be compromised

Engineering Contradiction:
Improveease of closingVSAvoidchild safety risk
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The closure mechanism is segmented into multiple independent components: the locking hook for primary engagement, the locking pin for securing the carriage position, and the guide element for controlled movement. This segmentation allows the system to provide easy operation through the simple locking hook engagement while maintaining child safety through the additional locking pin that prevents unintended opening.

Inventive Principle:
Principle #1Segmentation

3Reliability

If a complex closure mechanism with multiple components is used, then functionality and safety improve, but manufacturing cost and assembly complexity increase

Engineering Contradiction:
Improveclosure functionalityVSAvoidassembly capability
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The carriage component serves multiple functions: it carries the locking hook, provides the guide element for controlled movement, and incorporates the locking pin mechanism. This multi-functionality reduces the total number of separate components needed, simplifying assembly while maintaining the required functionality and safety features.

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

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 mechanism provides a functionally reliable, cost-effective, and safe closure with reduced closing force, enhanced assembly capabilities, and improved child safety features, suitable for household appliances.

Implementation Method 1

The carriage is loaded by a spring 5 towards the locking position

Methodology Applied
Scientific EffectSpring: Spring

Implementation Method 2

the locking hook is spring-mounted in the carriage

Methodology Applied
Scientific EffectSpring: Spring

Data Source

PatentEP1874174B1Dish washing machine
Publication Date: 2009.12.09 BSH HAUSGERATE GMBH
  • EP1874174B1 patent drawingFigure 1
  • EP1874174B1 patent drawingFigure 2
  • EP1874174B1 patent drawingFigure 3

AI summary

The invention relates to a lock (1) for a movable closing element (2), especially a door, a cover, a flap, or similar on a domestic appliance such as a dishwasher, a washing machine, a refrigerator, or similar. Said lock comprises a closing hook (6) which can be made to engage with the closing element when being closed and/or be made to disengage therefrom when being opened. The closing hook (6) can be made to engage with a cavity (7) in the closing element (2).