Headrest Sleeve Bushings for Quiet, Smooth Rod Sliding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sleeve devices for vehicle headrests face issues with noise due to tolerances and misalignment between rods and sleeves, leading to vibration and discomfort, and current solutions either fail to adequately dampen noise or are complex to manufacture.
Innovation Solution
The sleeve device incorporates slit or parted bushings made of thermoplastic elastomers, which are overmoulded to provide secure positioning and absorb vibrations, reducing noise and improving sliding smoothness by embracing intermediate portions of the sleeve body.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the sleeve and rod are designed to fit tightly to avoid gaps, then noise problems (BSR) are reduced, but the metal rods cannot slide smoothly along the sleeves
Solution Approach 1:
The patent introduces an intermediary element (elastomeric material or bushing) between the rod and sleeve body. This mediator absorbs vibrations and dampens noise while still allowing smooth sliding motion, thus resolving the contradiction between noise reduction and sliding smoothness
Solution Approach 2:
The patent changes the friction parameters by using elastomeric materials with specific friction characteristics. The elastomeric material provides sufficient friction to prevent gaps and noise while maintaining low enough friction to allow smooth sliding, thus optimizing both noise reduction and sliding ease
2Object-affected harmful factors
If elastomeric elements are added to dampen vibrations and reduce noise, then noise problems are reduced, but the device structure becomes more complex
Solution Approach 1:
The patent merges the elastomeric damping element with the existing sleeve structure by integrating it into the sleeve body or positioning it within the axial passage. This combination approach reduces the number of separate components and simplifies assembly while maintaining noise dampening functionality
Solution Approach 2:
The patent uses flexible elastomeric elements that can be formed as thin-walled structures or films within the sleeve assembly. These flexible elements provide vibration dampening without requiring thick, bulky materials, thus maintaining structural simplicity
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 effectively dampens vibrations and reduces noise issues like BSR (Buss Squeak Rattle) while maintaining a smooth sliding motion, addressing tolerance variances and manufacturing complexity.
Implementation Method 1
sleeve devices comprising bushings or rings of flexible material antifriction material to engage the sleeve body to the frame or to guide the rod in the axial inner passage of the sleeve body
Implementation Method 2
elastomeric elements are positioned between the head and the sleeve body so as to dampen the transmission of vibrations from the frame to the headrest
Implementation Method 3
FR-2917681-A1 discloses a sleeve device for headrests comprising a spacing dispersion adjustment device with elastomeric elements
Data Source
Figure 1
Figure 2~5
Figure 6~9
AI summary
A sleeve device for a headrest comprising a sleeve body (1) to be inserted into an opening in a frame of a vehicle seat, the sleeve body (1) comprising an inner axial passage (2) to accommodate a rod (18) of the headrest, the inner axial passage (2) including an inner wall (2a), a top end portion (2b) and a bottom end portion (2c); a head portion (3) ;an external side (1a); and an upper inner seat portion (6) at the inner the wall (2a) of the top end portion (2b) of the axial passage (2), the upper inner seat portion (6) for encircling an upper portion of the rod (18) of the headrest; and an upper inner bushing (7) or an upper or lower outer bushings overmoulded to a seat portion of the sleeve body (1), the bushings being made from an antifriction resilient plastic material.