Vehicle Seat Fitting Catch Design for Play Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle seat fittings with one or two catches face challenges in effectively reducing play due to static indeterminacy, impairing the effectiveness of play reduction and strength enhancement.
Innovation Solution
The fitting incorporates a catch composed of two tilted and braced catch parts with modified toothing, each interacting with a toothed ring, allowing for improved tooth overlap and play compensation through eccentric-driven torque application, enhancing strength and reducing play by compensating guide tolerances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fitting has only one or two catches, then the device complexity is reduced, but the play reduction effectiveness deteriorates due to static indeterminacy
Solution Approach 1:
Each catch is divided into two separate catch parts (first catch part and second catch part), allowing each part to independently interact with the toothed ring. This segmentation enables static determinate force generation even with only one or two catches, effectively reducing play while maintaining low device complexity
Solution Approach 2:
The catch parts are arranged at different angular positions around the eccentric axis, utilizing the circumferential dimension to create multiple force application points. This spatial arrangement transforms a single-catch system into a multi-directional force system, achieving play reduction equivalent to having more catches
2Strength
If the catch is split into multiple catch parts, then the strength and play reduction are improved, but the device complexity increases
Solution Approach 1:
Multiple catch parts are merged into a single integrated catch assembly that functions as one unit during operation. The catch parts share common mounting and actuation mechanisms, reducing the overall complexity increase despite having multiple force-generating elements
Solution Approach 2:
Each catch part serves multiple functions: it provides structural support, generates locking force through eccentric action, engages with the toothed ring for positioning, and contributes to play reduction. This multi-functionality reduces the need for additional separate components, minimizing complexity
3Strength
If the toothing of catch parts is modified for improved tooth overlap, then the strength is increased, but the manufacturing complexity increases
Solution Approach 1:
The toothing geometry parameters (such as tooth profile, pitch, and overlap dimensions) are optimized to achieve improved tooth engagement. By carefully selecting these parameters, the design achieves enhanced strength through better tooth overlap while maintaining manufacturability through standard gear manufacturing processes
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 solution effectively reduces play and increases strength in vehicle seat fittings, particularly with two catches, by optimizing catch design and interaction with the toothed ring, allowing for improved load distribution and reduced control travel, while maintaining low tolerance requirements for the clasp ring.
Implementation Method 1
a driveable eccentric (11), which is mounted so as to be rotatable about the axis, and at least one catch (13), which is guided by the first fitting part (7) so as to be movable in a radial direction with respect to the axis and which, for the locking of the fitting, can be moved radially outward under the action of the eccentric
Implementation Method 2
Each of the catch parts has a toothing for interacting with a toothing, in the form of a toothed ring, of the second fitting part
Data Source
AI summary
A fitting (5) for a vehicle seat, in particular for a motor vehicle seat, includes a first fitting part (7), a second fitting part (8) that can be rotated relative to the first fitting part (7) about an axis (A), a drivable eccentric (11), rotatably supported about the axis (A), and at least one catch (13), which is guided by the first fitting part (7) such as to be movable in a radial direction relative to the axis (A) and which moves radially outward under the action of the eccentric (11) to lock the fitting (5) and interacts radially outwardly with the second fitting part (8). The at least one catch (13) includes a first bar part (13a) and a second bar part (13b), each of which has teeth (13a′, 13b′) for interacting with teeth of the second fitting part (8) designed as a toothed ring (8a).