Household Appliance Hinge System with Cam and Spring

Solution Overview

Problem

Modern household appliances face challenges in maintaining proper compartment isolation while ensuring easy door opening and smooth door movement, as stronger hinges required for better sealing complicate the opening process and affect balance.

Innovation Solution

A hinge system with a base, joint, and tension spring, combined with a cam mechanism and optional shock absorber, which adjusts the closing force and smooths door operation by distributing the spring's traction effectively, enhancing stability and balance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a stronger main hinge spring is used to improve compartment isolation, then the sealing force increases, but the opening force required increases significantly

Engineering Contradiction:

Improvecompartment isolationVSAvoiddoor opening

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The hinge system is divided into two independent spring mechanisms: a first hinge spring for providing closing force to ensure sealing, and a second hinge spring (balancing spring) for assisting door opening and balancing. This segmentation allows each spring to be optimized for its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A balancing spring is introduced as an intermediary element that mediates between the heavy closing force requirement and the ease of opening requirement. The balancing spring compensates for the door's weight and the strong closing force, making the door easier to open while maintaining effective sealing.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If a stronger main hinge spring is used to improve compartment isolation, then the sealing force increases, but the door movement becomes less smooth

Engineering Contradiction:

Improvecompartment isolationVSAvoiddoor movement smoothness

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The hinge system is divided into two independent spring mechanisms: a first hinge spring for providing closing force to ensure sealing, and a second hinge spring (balancing spring) for assisting door opening and balancing. This segmentation allows each spring to be optimized for its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system changes the force parameters throughout the door's movement range by using two springs with different characteristics. The balancing spring provides higher force during opening to counteract weight, while the closing spring maintains optimal sealing force when closed, creating smooth acceleration and deceleration phases.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If a stronger main hinge spring is used to improve compartment isolation, then the sealing force increases, but the door becomes harder to balance

Engineering Contradiction:

Improvecompartment isolationVSAvoiddoor balance

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The hinge system is divided into two independent spring mechanisms: a first hinge spring for providing closing force to ensure sealing, and a second hinge spring (balancing spring) for assisting door opening and balancing. This segmentation allows each spring to be optimized for its specific function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The balancing spring functions as a counterweight mechanism, providing an upward force that compensates for the door's weight during opening. This counterbalancing effect makes the door easier to lift and improves overall balance, while the separate closing spring ensures proper sealing force is applied when the door is closed.

Inventive Principle:

Principle #8Anti-weight (Counterweight)

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 hinge system achieves improved compartment isolation and easier door opening with balanced movement, reducing the required opening force and enhancing the stability of the door in the closed position.

Implementation Method 1

a tension spring (8), having a first end (8A) secured to the base (5) and a second end (8B) secured to the intermediate element (9), wherein the tension spring (8) applies traction to the intermediate element (9) so as to push a cooperation surface (10) of the intermediate element (9) against the cam (13)

Methodology Applied

Scientific EffectElastic force: Elasticity

Data Source

PatentEP3868991B1Household appliance

Publication Date: 2022.10.12 BRERA CERNIERE

Figure 1~2
Figure 3~4
Figure 5~7

AI summary

A household appliance (1) is disclosed comprising a frame (2) equipped with an openable door (3), the door (3) being hinged to the frame (2) by means of at least one hinge (4), the hinge (4) comprising a base (5) connected to either the frame (2) or the door (3) and a joint (6) connected to the other left free of either the frame or the door, the joint (6) being hinged to the base (5) and to a tie rod (7) which is slidably secured to the base (5), the tie rod (7) being coupled with a tension spring (8) endowed with a first end (8A) secured to the base (5); a second end (8B) of the spring (8) is secured to an intermediate element (9) hinged to the tie rod (7), the intermediate element (9) featuring at least one surface (10) which cooperates, in at least certain joint (6) positions, with a first cam (13) in the base (5) to improve closure of the door (3).