Vehicle Backrest Lock with Segmented Pawl Mechanism

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing manual and automatic locking and inclination adjustment systems for motor vehicle seats are complex and expensive, requiring two drives for multi-part backrests, which is not cost-effective, and lack secure and convenient manual solutions that meet safety and manufacturing efficiency criteria.

Innovation Solution

A locking and inclination adjustment arrangement featuring a lock shackle on the body with rotary latches and pawls, allowing secure locking and adjustment of the backrest relative to the body, using separate actuating mechanisms for locking and unlocking, and a spring-assisted folding mechanism for easy operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If manual locking and inclination adjustment devices are used, then device complexity is reduced and cost is decreased, but ease of operation and user comfort are worsened compared to automatic systems

Engineering Contradiction:
Improvedevice complexityVSAvoidease of operation
Core Design Contradiction:
Device complexityVSEase of operation

Solution Approach 1:

The locking mechanism is segmented into distinct functional components: locking pawls for securing the backrest, inclination adjustment mechanism for angle control, and folding mechanism for backrest collapse. This segmentation allows each component to perform its specific function efficiently while keeping the overall system simple and cost-effective.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The mechanism incorporates dynamic elements including spring-loaded pawls that automatically engage and disengage, and a folding mechanism that allows the backrest to collapse forward under controlled motion. These dynamic features improve ease of operation while maintaining mechanical simplicity.

Inventive Principle:
Principle #15Dynamics

2Ease of operation

If automatic inclination adjustment devices with drives are used, then ease of operation is improved, but device complexity and manufacturing cost increase

Engineering Contradiction:
Improveease of operationVSAvoiddevice complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The locking and inclination adjustment mechanism is designed to be self-servicing through spring-loaded pawls that automatically engage with locking surfaces and spring-assisted folding action. This eliminates the need for external drives or actuators, reducing device complexity while maintaining ease of operation.

Inventive Principle:
Principle #25Self-service

3Ease of manufacture

If locking devices with lateral arrangement are used, then ease of manufacture is improved, but reliability and security of locking are worsened

Engineering Contradiction:
Improveease of manufactureVSAvoidreliability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The locking function and inclination adjustment function are merged into a single integrated mechanism with pawls that perform both locking and angle adjustment. This consolidation maintains lateral arrangement for ease of manufacture while improving reliability through unified, coordinated action of the locking components.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The locking surfaces and pawl engagement points are designed with curved or rounded geometries that facilitate reliable engagement and disengagement while maintaining lateral placement. The curved surfaces ensure proper alignment and secure locking without requiring complex lateral mechanisms.

Inventive Principle:
Principle #14Spheroidality (Curvature)

4Adaptability or versatility

If multiple drives are used for multi-part backrests, then adaptability and separate adjustment of backrest parts are improved, but device complexity and cost increase

Engineering Contradiction:
ImproveadaptabilityVSAvoiddevice complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The locking and inclination adjustment mechanism is designed as a universal system that can be applied to single-part or multi-part backrests. The same pawl-based mechanism handles both locking and inclination adjustment for each backrest section, providing adaptability without requiring separate drives for each part.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 provides a secure, cost-effective, and user-friendly manual locking and adjustment system that meets safety and manufacturing efficiency requirements, allowing for adjustable inclinations without compromising security, and can be easily integrated into existing backrest designs without modifying the body.

Implementation Method 1

a spring element, in particular a torsion spring, which acts on the first part of the backrest and causes the first part of the backrest to be folded automatically when the backrest lock is unlocked

Methodology Applied
Scientific EffectSpring: Spring

Data Source

PatentEP2768697B1Locking and inclination-adjusting arrangement, in particular backrest lock
Publication Date: 2018.12.05 VOLKSWAGEN AG
  • EP2768697B1 patent drawingFigure 1A
  • EP2768697B1 patent drawingFigure 1B
  • EP2768697B1 patent drawingFigure 1C

AI summary

The invention relates to a locking and inclination-adjusting arrangement for locking and adjusting the inclination of a component, in particular a pivotable backrest (R, R1, R2) of a vehicle, comprising a lock shackle (30) on the vehicle body and a lock (S) on the component, said lock being connected to the lock shackle (30) in a locking position (I, II) and it being possible for said lock to be released from the lock shackle (30) in an unlocking position (III). Provision is made for the lock (S) on the component to have catches (10, 20) with pawls (15, 25) which are associated with said catches and in which the component can be adjusted to various inclinations and locked in various latching positions (I, II), which can be released again, on the lock shackle (30) which engages in the lock (S) and can be moved to the unlocking position (III) separately from the lock shackle (30).