Vehicle Seat Locking Unit Dual Contact Point Crash Load Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle seat locking units face challenges in absorbing high crash loads, leading to potential failure in securing the locked state during severe impacts.
Innovation Solution
A locking unit design featuring a pivotably mounted rotary latch with a latching pawl that provides two contact points during deformation, utilizing a second contact point on the latching pawl to absorb crash loads, thereby increasing the load-absorption capacity and preventing the rotary latch from opening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a single contact point on the latching pawl is used to secure the rotary latch during a crash, then the locking unit can maintain a simple structure, but the load-absorption capacity is insufficient under high crash loads
Solution Approach 1:
The latching pawl is segmented to provide two distinct contact points (first contact point and second contact point) that engage with the rotary latch at different locations. This segmentation allows the single latching pawl component to distribute crash loads across multiple engagement points, increasing load-absorption capacity without adding separate structural components
Solution Approach 2:
The solution transitions from a single-point contact configuration to a multi-point contact configuration by utilizing different spatial locations on the latching pawl. The first contact point engages the rotary latch in the locked state, while the second contact point engages during deformation, effectively adding a dimensional aspect to the contact mechanism that increases capacity without proportionally increasing complexity
2Strength
If the rotary latch is allowed to deform during a crash, then additional contact points can be engaged to absorb load, but the reliability of the locking mechanism may be compromised
Solution Approach 1:
The latching pawl is pre-configured with the second contact point positioned such that it automatically engages with the rotary latch during deformation. This preliminary arrangement ensures that as the rotary latch deforms under crash load, the second contact point is already in position to provide additional support, maintaining reliability through predetermined geometric relationships rather than requiring active control
Solution Approach 2:
The deformation of the rotary latch, which could be considered a harmful effect indicating failure, is converted into a beneficial mechanism that triggers engagement of the second contact point. The deformation itself activates the redundancy by causing the rotary latch to contact the second point on the latching pawl, thereby absorbing additional load and maintaining the locked state
Data Source
AI summary
A locking unit (10) for a vehicle seat (1) includes a pivotally mounted rotary latch (20) for locking to a bolt (12), and a detent (30) which secures the locking unit (10) in the locked state in the event of a crash, in which the rotary latch (20) supports itself on a first contact point against the detent (30). The rotary latch (20) also supports itself on a second contact point in the event of a deformation of the latch (20) in the event of a crash. The second contact point is provided on the detent (30).