Slave Cylinder Seal Carrier Gap Extrusion Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing slave cylinders for hydraulic release systems in vehicles experience seal wear and damage due to gap extrusion, where parts of the seal are pressed into gaps between the annular piston and the housing or guide sleeve, leading to inefficiencies.
Innovation Solution
A slave cylinder design featuring a seal with radially spread V-shaped sealing lips on an annular piston, supported by a seal carrier with axial and radial play, and reinforcement, which expands to close gaps between the piston and housing or guide sleeve when pressure is applied, reducing friction and wear through a compressive force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional seal is used in the slave cylinder, then the seal can perform basic sealing function, but the seal is worn out or damaged by gap extrusion where parts of the seal are pressed into gaps between the annular piston and housing or guide sleeve
Solution Approach 1:
The patent applies preliminary anti-action by pre-compressing the seal between the seal carrier and the annular piston, creating a preliminary compressive force that counteracts the hydraulic pressure before it can cause gap extrusion. This pre-compression ensures the seal remains firmly seated and prevents it from being pressed into gaps during operation, thereby resolving the contradiction between basic sealing function and gap extrusion damage.
Solution Approach 2:
The patent changes the pressure distribution parameters by introducing a seal carrier that distributes the hydraulic pressure more evenly across the seal. This parameter change prevents concentration of force at specific points that would lead to gap extrusion, while maintaining effective sealing. The seal carrier modifies how pressure is applied, transforming the harmful localized compression into beneficial distributed compression.
2Reliability
If the seal is compressed to prevent gap extrusion, then gap extrusion is reduced, but friction and wear increase
Solution Approach 1:
The patent optimizes the compression parameter by carefully designing the seal carrier geometry and material properties to achieve the minimum necessary compressive force. This ensures the seal is sufficiently compressed to prevent gap extrusion while avoiding excessive compression that would generate harmful friction and wear. The parameter is tuned to the optimal range where sealing effectiveness is achieved without excessive wear.
Solution Approach 2:
The patent employs composite material strategies by selecting specific materials for the seal, seal carrier, and piston surfaces that reduce friction coefficients. The combination of materials is chosen to minimize wear while maintaining the necessary friction for sealing. This material selection allows the system to operate with lower friction and wear even under compressed conditions.
3Strength
If the annular piston is rigid to maintain structural strength, then structural integrity is ensured, but the piston cannot expand to close gaps under pressure
Solution Approach 1:
The patent segments the piston system into two functional parts: a rigid annular piston body that maintains structural integrity, and a compliant seal carrier that can deform under pressure. This segmentation allows the piston body to remain strong while the seal carrier expands to close gaps, resolving the contradiction between structural strength and gap closing capability.
Solution Approach 2:
The patent introduces a flexible seal carrier component that can deform elastically under hydraulic pressure. This flexible element is designed to expand radially when pressurized, enabling it to close gaps between the piston and housing or guide sleeve. The flexibility is carefully controlled to provide gap closing capability while maintaining sufficient structural support.
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 design effectively reduces annular gaps and prevents gap extrusion, enhancing the seal's durability and reducing wear, thereby improving the hydraulic release system's performance and longevity.
Implementation Method 1
When pressure is applied to the pressure chamber, the sealing part is compressed and subjected to a compressive force in the radial direction
Implementation Method 2
the sealing part is compressed and subjected to a compressive force in the radial direction. The radial compressive force spreads the part of the seal carrier or piston body surrounding the seal
Implementation Method 3
the sealing lips of which are spread apart, in particular radially spread apart in a V-shape... When pressure is applied to the pressure chamber, the radial compressive force spreads the part of the seal carrier or piston body surrounding the seal
Data Source
Figure 1
Figure 2~3
AI summary
Slave cylinder comprises an annular piston (6) having a region which decreases an annular gap (23) between the piston and a housing (2) and/or an annular gap (24) between the piston and a guiding sleeve when a pressure chamber (9) is impinged with pressure. Preferred Features: The piston has a piston body (45) connected to a seal support (7) for holding a seal (8). The seal support is clipped to the piston body.