Automotive Backrest Locking Device Anti-Pinch Bellows

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Solution Overview

Problem

Conventional multi-position locking devices for motor vehicle rear seat backrests lack adequate safety measures to prevent accidental finger pinching or crushing during adjustment of the backrest inclination, as the protruding striker plate portion can inadvertently trap fingers or objects.

Innovation Solution

Incorporation of an anti-pinching protection mechanism featuring a bellows that surrounds the protruding portion of the striker plate and a U-shaped metal striker wire, with a rigid closing element to prevent accidental insertion, combined with motorized locking means for continuous adjustment and a rack-and-pinion system for precise positioning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a multi-position locking device with a protruding striker plate is used to allow continuous adjustment of backrest inclination, then adaptability and ease of operation are improved, but the risk of finger pinching or crushing increases

Engineering Contradiction:

Improvebackrest inclination adjustmentVSAvoidfinger pinching risk

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

A bellows component is introduced as an intermediary protective element between the protruding striker plate and the user's fingers. The bellows extends from the support box front face and surrounds the protruding portion of the striker plate, creating a physical barrier that prevents direct contact while allowing the locking mechanism to function normally.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The bellows is positioned in advance to prevent the harmful action of finger pinching before it can occur. By permanently surrounding the protruding striker plate portion, the bellows proactively blocks the potential hazard zone, eliminating the risk of accidental insertion or crushing during backrest adjustment.

Inventive Principle:

Principle #9Preliminary anti-action

2Device complexity

If a conventional single-position locking device is used, then device complexity is reduced, but adaptability of backrest inclination is limited

Engineering Contradiction:

Improvelocking mechanismVSAvoidbackrest inclination positions

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The locking device transitions from a static single-position mechanism to a dynamic multi-position system. The striker plate can move along an arcuate trajectory defined by the bellows, allowing the backrest to be locked at multiple inclination positions while maintaining a relatively simple overall structure.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The locking mechanism is segmented into distinct functional components: the support box, the protruding striker plate, the bellows protective covering, and the locking means. This segmentation allows each component to perform its specific function while contributing to the overall multi-position capability without excessive complexity.

Inventive Principle:

Principle #1Segmentation

3Object-affected harmful factors

If a bellows protective covering is added to surround the striker plate, then safety against finger pinching is improved, but device complexity increases

Engineering Contradiction:

Improvefinger pinching preventionVSAvoidlocking device structure

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

A bellows component, which is a flexible accordion-like structure, is used to provide protective coverage. The bellows can expand and contract to accommodate the movement of the striker plate while maintaining continuous protection, adding minimal structural complexity compared to rigid protective covers.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The protection is achieved by adding a dimensional element (the bellows extending outward from the support box front face) rather than complicating the internal mechanism. This external protective dimension surrounds the hazard zone without interfering with the internal locking mechanism's operation.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP3390146B1Multi-position locking device of a backrest of a rear seat of an automotive vehicle

Publication Date: 2020.12.30 PSA AUTOMOBILES SA

Figure 1~3
Figure 4~8

AI summary

The invention relates to a locking device for a foldable backrest, comprising a lock connected to said backrest and a strike housed in a casing connected to the structure of the vehicle (130) and comprising a plate (121) having a slot (122) through which a guide member (131) secured to said casing (130) passes, said plate (121) being extended by a coupling member (123) intended to come into engagement with a bolt of said lock; said strike being able, while remaining in engagement with said lock, to slide in said casing (130) through a predetermined travel and to be locked to the latter in several positions, a portion of said slot (122) protruding from said casing (130) along a part of said travel; said device also comprising anti-pinch means that comprise a gusset (140) that extends in front of said casing (130) and is arranged so as to permanently surround said protruding portion.