Axial Locking Conical Contact Hydraulic Selection System

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing hydraulic device selection and braking systems face issues with axial stop mechanisms that are not stressed along their axis of greatest resistance, leading to functional clearance and potential breakage due to dimensional requirements and segmented assembly, which results in bending and punctual force application.

Innovation Solution

A selection system featuring a sleeve with a conical base and shell portions that form a conical contact, allowing for flat plane contact and distributing forces axially and radially to prevent misalignment and concentration of stress, using a spring washer for orientation and movement adjustment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If stop pieces are segmented into several pieces to allow assembly around a shaft, then ease of manufacture and assembly is improved, but functional clearance increases causing bending and punctual force application leading to breakage

Engineering Contradiction:
Improveease of assemblyVSAvoidrisk of breakage
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The shell is divided into two separable portions (first shell portion and second shell portion) that can be assembled around the connecting rod independently, then joined together to form the complete stop mechanism

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The first and second shell portions are joined together to form a unified shell structure that provides continuous support around the connecting rod, eliminating gaps and ensuring uniform force distribution

Inventive Principle:
Principle #5Merging (Combining)

2Volume of moving object

If dimensional requirements are reduced to achieve high force recovery in reduced space, then compactness is improved, but the stop pieces cannot be properly assembled around the shaft

Engineering Contradiction:
Improvespace occupationVSAvoidassembly feasibility
Core Design Contradiction:
Volume of moving objectVSEase of manufacture

Solution Approach 1:

The segmented shell portions are designed to be assembled around the connecting rod in a nested manner, where each portion fits over the rod sequentially and then joins with the other portion to form the complete structure

Inventive Principle:
Principle #7Nested doll (Nesting)

3Ease of operation

If stop pieces are designed with significant functional clearance to allow assembly, then ease of assembly is improved, but bending occurs and forces are applied punctually causing breakage

Engineering Contradiction:
Improveassembly easeVSAvoidresistance to breakage
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The stop mechanism incorporates a spring element that provides dynamic adjustment and compensation, allowing the rigid shell portions to maintain precise alignment and force distribution while accommodating assembly variations and operational movements

Inventive Principle:
Principle #15Dynamics

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 system effectively supports high forces in a reduced space, reduces the risk of breakage by distributing forces through flat surfaces, and maintains alignment and concentricity, enhancing the stability and reliability of hydraulic machine components.

Implementation Method 1

a base having symmetry of revolution and comprising a conical portion, a shell comprising two shell portions each comprising a conical portion configured to bear flat against the conical portion of the base

Methodology Applied
Scientific EffectConical contact: Geometry

Implementation Method 2

The system can then further comprise an orientation washer. The shell is then in abutment against the slewing ring which is itself in abutment against the second shoulder formed on the connecting rod. This orientation washer is typically formed by a spring washer.

Methodology Applied
Scientific EffectSpring elasticity: Spring

Data Source

PatentEP3252307B1Selection system comprising improved axial locking
Publication Date: 2019.09.04 POCLAIN HYDRAULICS IND
  • EP3252307B1 patent drawingFigure 1~10
  • EP3252307B1 patent drawingFigure 3~6
  • EP3252307B1 patent drawingFigure 7~9

AI summary

Selection system (1), comprising - a sleeve (4) defining an internal housing extending along a longitudinal direction, - a connecting rod (3) disposed in said internal housing, and extending along the longitudinal direction, - a selection drawer (2) mounted to slide in the internal housing, around the connecting rod (3), the connecting rod (3) being mounted fixed in translation along the longitudinal direction relative to the sleeve (4) via stop means (6, 7), characterized in that the stop means (6, 7) comprise - a base (6) having a symmetry of revolution and comprising a conical portion (61), - a shell (7) having a symmetry of revolution and comprising a conical portion (7D3) configured to bear planarly against the conical portion (61) of the base (6).