Hidden Finger Protection Roller for Heavy Doors

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Solution Overview

Problem

Existing door designs with finger protection devices fail to meet requirements for aesthetics, strength, and safety, particularly in public spaces like kindergartens and schools, as they are either visible and distracting or not robust enough to handle heavy doors.

Innovation Solution

A door design that incorporates a hidden finger protection roller with a spring-loaded protective strip, where the roller is integrated into the door frame and hinge area, ensuring the protection mechanism is concealed from view and robust enough for heavy use, while maintaining a harmonious appearance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a finger protection device is installed on the door, then finger safety is improved, but the aesthetic appearance of the door deteriorates due to visible protection mechanisms

Engineering Contradiction:
Improvefinger injury preventionVSAvoidaesthetic appearance
Core Design Contradiction:
Object-affected harmful factorsVSShape

Solution Approach 1:

The finger protection roller is extracted from the visible door surface and relocated to the hinge area, where it is concealed by the door frame and hinge structure. This allows the protective function to be maintained while removing the visual distraction from the door's aesthetic surface.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The door frame and hinge structure serve as intermediaries that conceal the protection roller. The roller is positioned in the hinge area where it is hidden by these structural elements, allowing the protective function to be provided without directly impacting the visual appearance of the door leaf.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Strength

If the door dimensions are increased for public spaces, then the door strength requirement is improved, but the weight of the door increases

Engineering Contradiction:
Improvedoor strengthVSAvoiddoor weight
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The hinge system is designed with dynamic characteristics, including a spring mechanism that provides progressive resistance during door closing. This allows the hinge to support heavy doors while maintaining smooth operation and reducing the perceived weight during operation.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The door and frame structures utilize composite construction methods and materials that provide high strength-to-weight ratios. This allows large doors to be constructed with sufficient strength while minimizing unnecessary weight, improving operational efficiency.

Inventive Principle:
Principle #40Composite materials

3Productivity

If the door and frame are designed to maximize clear width, then the productivity of space utilization is improved, but the structural strength may deteriorate

Engineering Contradiction:
Improvespace utilizationVSAvoidstructural strength
Core Design Contradiction:
ProductivityVSStrength

Solution Approach 1:

The hinge and frame structures are designed to utilize the third dimension (depth) more effectively. By optimizing the spatial arrangement of structural elements in the depth direction, the clear width in the horizontal direction is maximized while maintaining sufficient structural strength through vertical and depth-wise reinforcement.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 solution effectively prevents finger injuries by hiding the protection mechanism, ensuring a safe and aesthetically pleasing door that meets the strength and safety demands for public spaces without compromising the door's appearance or functionality.

Implementation Method 1

A spring arranged in the finger protection roller 5 and not visible here has drawn in the protective strip 5.1.

Methodology Applied
Scientific EffectSpring: Spring

Data Source

PatentEP3144462B1Door with a finger protection system
Publication Date: 2018.06.06 KOEHNLEIN GMBH 74597 STIMPFACH DE
  • EP3144462B1 patent drawingFigure 1~2
  • EP3144462B1 patent drawingFigure 3~4
  • EP3144462B1 patent drawingFigure 5~6

AI summary

The invention relates to a door comprising: - a frame; - a door leaf; - a hinge for connecting the frame and the door leaf; - a finger guard roller parallel to the door leaf, the protective strip of which covers the space between the frame and the door leaf. The door according to the invention is characterized by the following features: - the frame, viewed in a horizontal section, has a hollow profile that is at least approximately U-shaped, comprising a web and two legs; - the frame is a separate component that is connected to the door leaf in such a way that a cavity remains between the end face of the door leaf and the frame; - the finger guard roller is located in the cavity of the profile; - the web of the U has a slot for guiding the protective strip through it.