Vehicular Door Mirror Folded Retention Mechanism

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Solution Overview

Problem

In small-sized vehicular door mirrors, the space constraints make it difficult to set recessed and protrusion engagement portions for the folded storage position, leading to potential damage when external forces, like those from a car washing machine, cause unintended unfolding.

Innovation Solution

A vehicular door mirror design where a protrusion portion on the groove top face slides over and engages with a protrusion portion at the rotation regulating piece, allowing the door mirror unit to be securely retained in the folded storage position, even under external forces, with a sense of click indicating proper storage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If recessed and protrusion engagement portions are provided for both deployed use position and folded storage position, then both positions can be appropriately retained, but in small sized door mirror units, it becomes difficult to set the recessed and protrusion engagement portion at the rotation position corresponding to the folded storage position due to space constraints

Engineering Contradiction:
Improveretention of folded storage positionVSAvoidspace for engagement portions
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The engagement mechanism is segmented into two independent systems: a rotation moderation mechanism with recessed and protrusion portions for the deployed use position, and a separate rotation regulating mechanism with a rotation regulating groove and rotation regulating piece for the folded storage position. This segmentation allows each mechanism to be optimized for its specific function without interfering with the other, resolving the space constraint issue in small-sized door mirrors.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The retention function for the folded storage position is extracted from the rotation moderation mechanism and implemented as a separate rotation regulating mechanism. The rotation regulating groove is provided on the bearing portion while the rotation regulating piece is provided on the shaft, creating an independent engagement system that does not require additional space on the already constrained shaft surface.

Inventive Principle:
Principle #2Taking out (Extraction)

2Volume of moving object

If the door mirror unit is small sized, then the overall size is reduced, but it becomes difficult to set the recessed and protrusion engagement portion at the rotation position corresponding to the folded storage position

Engineering Contradiction:
Improvesize of door mirror unitVSAvoidsetting of engagement portions
Core Design Contradiction:
Volume of moving objectVSEase of manufacture

Solution Approach 1:

The engagement mechanism transitions from a two-dimensional surface arrangement (where multiple engagement portions would compete for limited shaft surface area) to a three-dimensional arrangement using the radial depth of the bearing portion. The rotation regulating groove extends radially inward from the outer circumference, allowing the engagement portions to be positioned in the radial dimension rather than competing for circumferential space on the shaft surface.

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

This design effectively prevents damage from external forces and ensures the door mirror unit is securely stored, providing a reliable and space-efficient solution for retaining the folded position without relying on the rotation moderation mechanism for deployed use.

Implementation Method 1

a protrusion portion of a groove top face comes into sliding contact with and rides over a protrusion portion at an upper edge of a rotation regulating piece

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

these protrusion portions drop and engage

Methodology Applied
Scientific EffectNormal force: Force

Data Source

PatentEP3141429B1Vehicular door mirror
Publication Date: 2019.08.14 ICHIKOH IND LTD
  • EP3141429B1 patent drawingFigure 1
  • EP3141429B1 patent drawingFigure 2
  • EP3141429B1 patent drawingFigure 3(A)~3(B)

AI summary

Provided is a vehicular door mirror capable of configuring an engagement structure for holding a folded storage position of a door mirror unit without design problems. When a door mirror unit (3) is rotated from a deployed use position (P2) to a folded storage position (P1), a protrusion portion (39) disposed on a groove upper surface of a rotation regulating groove (37) of a bearing portion (33) on the door mirror unit (3) side slidably contacts and rides over, during the rotating process, a protrusion portion (25) disposed on the upper edge of a rotation regulating piece (23) of a shaft (2) until the protrusion portions fall into a mutual engagement, whereby the folded storage position (P1) of the door mirror unit (3) is held.