Plastic Nut Fastening Device with Offset Head for Secure Locking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing fixing devices with plastic nuts lack effective locking mechanisms, requiring excessive pivoting angles and failing to provide clear visual indication of the locked state, while also not fully covering the support element opening.

Innovation Solution

A fixing device with a head having an elongated cross-section offset angle of 5 to 25 degrees, featuring abutment surfaces that limit pivoting to this angle, ensuring the head covers the opening upon locking, and incorporating clipping lugs for enhanced retention, allowing for easier implementation and visual confirmation of the locked state.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a plastic nut with no support head is used, then the device structure is simple, but the field of application is limited and blocking capability is absent

Engineering Contradiction:
Improvestructure simplicityVSAvoidfield of application
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent combines the support head and the nut body into a single integrated component. The support head is formed as an extension of the nut body, merging two previously separate elements (nut and support head) into one unified structure that provides both fastening and blocking functions simultaneously.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If stop surfaces are provided to limit rotation to 90 degrees, then the nut can be blocked, but the angular amplitude is excessive and implementation is tedious

Engineering Contradiction:
Improveblocking capabilityVSAvoidpivoting angle
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent changes the key parameter of the pivoting angle from 90 degrees to a reduced angle of 5-25 degrees. This is achieved by designing the abutment surface geometry and its relative position to the opening, which naturally limits the rotation to a smaller, more convenient angular range while maintaining effective blocking capability.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If a circular shaped bearing head is used, then the nut can be blocked with reduced pivoting angle, but the opening is never entirely covered and visual identification of locked state is impossible

Engineering Contradiction:
Improvepivoting angleVSAvoidvisual identification of locked state
Core Design Contradiction:
Ease of operationVSDifficulty of detecting and measuring

Solution Approach 1:

The patent replaces the circular (symmetric) bearing head with an asymmetric head shape that is complementary to the elongated opening. This asymmetric design allows the head to cover the entire opening when locked, providing clear visual indication of the locked state, while maintaining the reduced pivoting angle benefit.

Inventive Principle:
Principle #4Asymmetry

4Ease of operation

If the head cross-section is smaller than the opening, then the nut can pivot freely, but the opening is never entirely covered at any state

Engineering Contradiction:
Improvepivoting capabilityVSAvoidopening coverage
Core Design Contradiction:
Ease of operationVSArea of stationary object

Solution Approach 1:

The patent designs the head cross-section to be dynamically complementary to the opening - smaller when unpivoted to allow free insertion and pivoting motion, but larger when locked to entirely cover the opening. The head's elongated cross-section in the offset direction ensures full coverage of the elongated opening when the nut is in the locked position.

Inventive Principle:
Principle #15Dynamics

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

Facilitates easier locking with reduced pivoting angles and provides a clear visual indication of the locked state, while ensuring the nut is securely retained on the support element, enhancing both ease of use and locking efficiency.

Implementation Method 1

a plastic nut pierced, in an axial direction, with a hole adapted to conform by plastic deformation to the contour of an externally threaded element

Methodology Applied
Scientific EffectPlastic deformation: Plasticity

Data Source

PatentEP2446155B1Plastic nut fastening device
Publication Date: 2013.04.17 A RAYMOND & CO SCS
  • EP2446155B1 patent drawingFigure 1~2
  • EP2446155B1 patent drawingFigure 3~4

AI summary

The invention relates to a device for attachment onto a supporting element (11) which comprises a plastic nut (10) including a body (14) axially insertable into an elongate opening (12) of the supporting element (11). The cross-section of the body (14) matches the opening (12) and is elongate in a first main direction (Z1) such that the nut (10) is inserted through the opening (12) and then locked by means of the pivotal movement with a bearing head (15). At least one abutment surface limits the pivotal movement of the nut (10). The head (15) has a shape matching the opening (12), with an elongate cross-section in a second main direction (Z2) forming an offset angle (a) of 5 to 25 degrees with the first main direction (Z1). The abutment surface is configured so as to limit the pivotal movement of the nut (10) relative to the opening (12) at an angle substantially identical to said offset angle (a), such that the head (15) covers the entire opening (12) when locking the nut (10).