Piston Accumulator Sliding Layer Eliminates Guide Rings

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Solution Overview

Problem

Current piston accumulators are expensive and complex to manufacture due to the need for guide rings and support rings, which are costly and require separate fitting.

Innovation Solution

A piston accumulator design that eliminates the need for guide rings and support rings by using a sliding layer on the piston or housing wall, allowing for adjustable clearance and integration of the sliding layer within the piston material, enabling cost-effective and simplified assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If guide rings and support rings are used in the piston accumulator, then the piston can be stored and guided properly and the sealing ring is protected against extrusion, but the manufacturing cost increases and the assembly becomes complex

Engineering Contradiction:
Improvepiston storage and guidanceVSAvoidassembly complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the functions of guide rings and support rings into the piston structure itself. The piston is designed with an integrated guide function through its geometric shape and material properties, eliminating the need for separate guide rings. The piston body acts as its own support structure, integrating multiple functions into a single component.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The piston is designed to guide and support itself through its own structural features. The piston's geometry and material properties enable it to maintain proper positioning and protect the sealing ring without requiring external guide rings or support rings. The system uses its own components to fulfill multiple functions.

Inventive Principle:
Principle #25Self-service

2Reliability

If guide rings and support rings are installed separately, then proper piston guidance and seal protection are achieved, but the manufacturing cost increases due to separate fitting requirements

Engineering Contradiction:
Improveseal protectionVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The protective function previously requiring separate support rings is integrated into the piston structure. The piston design incorporates features that inherently protect the sealing ring from extrusion, eliminating the need for additional support ring components and their associated manufacturing and assembly costs.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent employs a cost-effective piston design that integrates guidance and support functions directly into the piston body, avoiding the need for expensive separate guide rings and support rings. The integrated design reduces component count and manufacturing complexity while maintaining protective functions.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Device complexity

If a plastic piston is used with integrated sliding layer, then the clearance can be adjusted and guide rings become unnecessary, but the manufacturing process requires precision molding

Engineering Contradiction:
Improvenumber of componentsVSAvoidclearance adjustment precision
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent adjusts the clearance parameters through precision molding of the plastic piston. The molding process controls the piston dimensions and surface characteristics to achieve the desired clearance between the piston and housing, eliminating the need for separate adjustment mechanisms or guide rings.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The plastic piston material is selected and processed to provide both structural integrity and appropriate surface properties for sliding. The composite nature of the molded plastic structure allows integration of the sliding surface directly into the piston body, combining multiple functions in a single material system.

Inventive Principle:
Principle #40Composite materials

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 simplifies assembly, reduces manufacturing costs, and enhances tribological properties, eliminating the need for separate guide and support rings, while maintaining gas tightness and sealing effectiveness.

Implementation Method 1

A sliding layer 6 is assigned to the piston 5 in such a way that the piston 5 can be moved along the housing wall 4 free of guide rings 7

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP2397701B1Piston accumulator
Publication Date: 2015.10.14 CARL FREUDENBERG KG
  • EP2397701B1 patent drawingFigure 1
  • EP2397701B1 patent drawingFigure 2

AI summary

A piston accumulator (1), comprising a housing (2) with a pressure chamber (3) which is bounded by a housing wall (4) and a piston (5), wherein the piston (5) is movable relative to the housing (2), wherein the volume of the pressure chamber (3) is variable and wherein the piston (5) is slidably displaceable along the housing wall (4), is characterized with regard to the task of creating a piston accumulator whose piston can be manufactured and assembled without difficulty, in that a sliding layer (6) is assigned to the piston (5) and/or the housing wall (4) such that the piston (5) is movable along the housing wall (4) free of guide rings (7).