Hydraulic Clutch Pipe Offset Devices for Air Bubble Evacuation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Air bubbles in the hydraulic fluid of clutch control devices, particularly in vehicles with rear powertrains, hinder proper operation by preventing full transmission of clutch engagement and disengagement, potentially leading to vehicle immobilization due to the longer hydraulic lines making bubble evacuation difficult.

Innovation Solution

The implementation of pipe misalignment devices along the hydraulic line, which trap air bubbles and facilitate their gradual rise to the reservoir through a series of offset modules, eliminating the need for additional purge equipment or separate circuits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the hydraulic line length is increased to accommodate rear powertrain configurations, then the vehicle layout flexibility is improved, but the difficulty of air bubble evacuation increases

Engineering Contradiction:

Improvevehicle layout flexibilityVSAvoidair bubble evacuation difficulty

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The hydraulic line is segmented into multiple sections by incorporating offset devices at different locations along the line. Each offset device creates a local high point that acts as an independent air trapping zone, breaking the long hydraulic line into manageable segments for air evacuation.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Offset devices are introduced as intermediary elements along the hydraulic line. These devices create intermediate collection points for air bubbles, allowing air to be gradually evacuated in stages rather than requiring direct evacuation from the far end of a long hydraulic line.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If conventional hydraulic control devices are used without offset devices, then the device complexity is reduced, but air bubbles accumulate in the hydraulic line preventing proper clutch operation

Engineering Contradiction:

Improvehydraulic control structureVSAvoidclutch operation reliability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The offset devices introduce a vertical dimension to the otherwise horizontal hydraulic line. By creating upward offsets, the system utilizes the vertical direction as an additional dimension for air bubble separation and evacuation, allowing air to rise naturally to collection points without complex mechanical components.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Reliability

If purge pumps or separate circuits are added to evacuate air bubbles, then the air evacuation effectiveness is improved, but the device complexity and cost increase

Engineering Contradiction:

Improveair evacuation effectivenessVSAvoidpurge equipment complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The hydraulic system performs its own air evacuation function through the offset devices created in the hydraulic line. The system uses its own operating fluid flow and the natural buoyancy of air bubbles to evacuate air, without requiring external purge pumps or separate evacuation circuits.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The natural buoyancy of air bubbles, which initially causes problems by allowing air to accumulate in the hydraulic line, is converted into a benefit. The offset devices harness this buoyancy force to naturally guide air bubbles upward into collection points where they can be evacuated, eliminating the need for active purge mechanisms.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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

Ensures effective evacuation of air bubbles during clutch operation, ensuring proper hydraulic control device function without the requirement for expensive additional equipment, such as purge pumps or separate circuits, across various vehicle configurations.

Implementation Method 1

the bubbles coming from the slave cylinder rise naturally in the master cylinder where they are then evacuated to the reservoir

Methodology Applied

Scientific EffectBuoyancy: Archimedes' Principle (Buoyancy)

Data Source

PatentEP3057820B1Device for hydraulic control of a clutch and associated vehicle

Publication Date: 2020.04.29 RENAULT SA

Figure 1~2
Figure 3~5

AI summary

Device for hydraulic control of a clutch for a motor vehicle (1), comprising a master cylinder (2) controlled by a clutch pedal (3), means for supplying the master cylinder (2) with hydraulic fluid (6), a receiving cylinder for actuation of the clutch (5), the master cylinder (2) being linked to the actuating receiver cylinder (6) by means of a hydraulic pipe (4), the cylinder for actuation of the clutch (5) being positioned in the rear of the vehicle and the pedal (3) and the master cylinder (2) being placed at the front of the vehicle, the hydraulic pipe (4) linking the front and rear of the vehicle comprising a plurality (8a, 8b, 8c, 8d) of pipe offset devices (8) along its length in order to encourage the return of air bubbles to the means for supplying the master cylinder (2) with hydraulic fluid (6).