Welded Hydraulic Accumulator Housing Design

Solution Overview

Problem

The high production costs of hydraulic accumulators, particularly for low-pressure accumulators, due to complex manufacturing processes and the need for replaceable components, hinder cost-effective production and efficient energy storage solutions.

Innovation Solution

The accumulator housing is designed as a closed, welded construction using deep-drawn metallic half-shells with a small bore for the bladder connection, eliminating the need for detachable parts and allowing for efficient, inexpensive production of a 'disposable' accumulator with enhanced structural strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of repair

If the accumulator housing is designed with detachable connections and sealing means for opening the housing, then the accumulator bladder can be replaced in the event of damage, but the production costs and device complexity increase due to additional sealing means and assembly requirements

Engineering Contradiction:

Improvereplaceability of accumulator bladderVSAvoidcomplexity of housing construction with detachable connections

Core Design Contradiction:

Ease of repairVSDevice complexity

Solution Approach 1:

The patent applies the disposable principle by designing the accumulator housing as a permanently sealed welded construction. The accumulator bladder is installed before welding and cannot be replaced afterward, transforming the accumulator into a disposable unit. This eliminates the need for complex detachable connections, sealing means, and maintenance infrastructure, significantly reducing production costs and device complexity while accepting that the entire unit must be replaced rather than serviced.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

2Ease of operation

If a borehole of sufficient size is provided for assembly or replacement of the bladder, then the bladder can be installed or removed, but the structural strength of the container is reduced

Engineering Contradiction:

Improveaccessibility for bladder installationVSAvoidstructural strength of container

Core Design Contradiction:

Ease of operationVSStrength

Solution Approach 1:

The patent applies preliminary action by installing the accumulator bladder into the housing before the welding process closes the housing. The bladder is positioned and secured during the assembly phase while the housing is still open, allowing access without requiring large boreholes in the finished structure. Once installed, the housing is welded shut, creating a strong sealed container that maintains full structural strength while having provided adequate access during the preliminary installation phase.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If the shells are made with complex manufacturing processes to ensure durability and replaceability, then the accumulator can be serviced, but the production costs increase

Engineering Contradiction:

Improvedurability of accumulator housingVSAvoidproduction cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent applies the disposable principle by designing the accumulator housing as a permanently sealed welded construction. The accumulator bladder is installed before welding and cannot be replaced afterward, transforming the accumulator into a disposable unit. This eliminates the need for complex detachable connections, sealing means, and maintenance infrastructure, significantly reducing production costs and device complexity while accepting that the entire unit must be replaced rather than serviced.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Data Source

PatentEP3094866B1Hydraulic accumulator

Publication Date: 2020.01.08 HYDAC TECH GMBH

Figure 1
Figure 2

AI summary

A hydraulic accumulator, in particular a low-pressure accumulator, has an accumulator housing (2) and a separating element, in particular in the form of an accumulator bladder (22) separating two media chambers (3, 5) in the housing (2). The accumulator housing (2) is formed of at least two shells (8, 10) welded together at their opposing end regions (24).