Striker Cap Composition for Noise Reduction and Moisture Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional striker caps made of PA66 materials deform in high-temperature and high-humidity environments, leading to noise issues and separation from strut rods due to moisture absorption, and existing noise reduction methods like grease application are ineffective over time.
Innovation Solution
A composition for the striker cap comprising a first compound of polyamide resin and inorganic filler, and a second compound of polyamide resin and polyolefin-based additive, with specific weight ratios and manufacturing processes to enhance noise reduction and separation force, eliminating the need for grease and preventing dimensional deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional PA66 material is used for striker cap, then manufacturing cost is low and ease of manufacture is good, but in high-temperature and high-humidity environment the striker cap deforms due to moisture absorption causing separation from strut rod and generating noise
Solution Approach 1:
The patent uses a composite material consisting of polyamide resin (PA6 or PA66) and polyolefin-based additive (ethylene-propylene-diene copolymer or polypropylene) to create a striker cap that maintains dimensional stability in high-temperature and high-humidity environments. The polyolefin-based additive prevents moisture absorption-induced deformation while maintaining structural integrity, resolving the reliability issue without requiring overly complex material systems.
Solution Approach 2:
The patent changes the material parameters by incorporating specific amounts of polyolefin-based additive (5-50 parts by weight per 100 parts of polyamide resin) to alter the moisture absorption characteristics and dimensional stability of the striker cap material, enabling it to withstand high-temperature and high-humidity conditions without deformation.
2Object-affected harmful factors
If grease is applied to the contact surface between striker cap and bump stopper to reduce noise, then noise reduction is improved initially, but the effect decreases rapidly as mileage increases and noise problem increases when shock absorber oil is adsorbed on the surface
Solution Approach 1:
The patent makes the striker cap material itself provide noise reduction functionality through its inherent low-friction surface properties derived from the polyolefin-based additive, eliminating the need for external grease application. The material self-maintains its noise reduction capability over time without requiring periodic reapplication of lubricants, as the polyolefin-based additive provides sustained low-friction characteristics.
Solution Approach 2:
The polyolefin-based additive acts as an intermediary substance within the material matrix that provides low-friction surface properties, mediating the interaction between the striker cap and bump stopper to reduce noise without requiring external grease. This internal intermediary prevents direct high-friction contact while being resistant to degradation by shock absorber oil.
3Force
If polyamide resin is used for striker cap, then basic mechanical properties are satisfied, but the separation force between striker cap and strut rod is insufficient in high-temperature and high-humidity environment
Solution Approach 1:
The patent creates a composite material system combining polyamide resin with polyolefin-based additive to enhance the separation force between the striker cap and strut rod. The polyolefin-based additive creates a low-friction interface that increases the force required for separation, preventing the striker cap from detaching during vibration and impact in high-temperature and high-humidity conditions.
Solution Approach 2:
The patent modifies the material parameters by incorporating polyolefin-based additive to change the surface friction characteristics and interfacial bonding properties, thereby increasing the separation force required to detach the striker cap from the strut rod while maintaining a relatively simple material composition.
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 improves noise reduction properties, enhances separation force, and prevents physical property deterioration, reducing costs and maintaining performance in varying environmental conditions.
Implementation Method 1
Generally, grease may be applied to the contact surface between the striker cap and bump stopper in order to reduce noise caused by friction therebetween
Implementation Method 2
the striker cap should not generate noise... in a high-temperature and high-humidity environment, a striker cap made of a conventional PA66 material is deformed by moisture absorption
Data Source
AI summary
Disclosed are a composition for a striker cap with improved noise and separation force, a striker cap, and a method for manufacturing a striker cap. The method for manufacturing a striker cap includes: preparing a first compound by compounding a first polyamide resin and an inorganic filler; preparing a second compound by compounding a second polyamide resin and a polyolefin-based additive; blending the first compound and the second compound to obtain an admixture; and injecting the admixture.