Speed Change Device Independent Centrifugal Hydraulic Pressure Cancellation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing speed change devices with shared centrifugal hydraulic pressure cancellation chambers for clutches C3 and C4 suffer from inadequate cancellation performance, leading to insufficient fuel efficiency due to the need for enhanced hydraulic pressure, which degrades vehicle performance.

Innovation Solution

The speed change device includes a drum member with independently adjustable centrifugal hydraulic pressure cancellation chambers for each clutch, utilizing separate recessed portions and oil passages to set the zero base point of centrifugal hydraulic pressure independently for the first and second centrifugal hydraulic pressure cancellation chambers, allowing for improved cancellation performance adjustments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a common recessed portion is used to supply working oil to both centrifugal hydraulic pressure cancellation chambers, then the device complexity is reduced, but the cancel performance for each clutch cannot be adjusted independently

Engineering Contradiction:

Improveadjustability of cancel performanceVSAvoidcomplexity of oil supply structure

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The common recessed portion is segmented into a first cancellation chamber recessed portion and a second cancellation chamber recessed portion. Each recessed portion independently supplies working oil to its respective centrifugal hydraulic pressure cancellation chamber, enabling independent adjustment of cancel performance for each clutch while maintaining a relatively simple overall structure.

Inventive Principle:

Principle #1Segmentation

2Reliability

If the rigidity of the return spring is enhanced to improve cancel performance, then the cancel performance is improved, but the hydraulic pressure required for clutch engagement increases

Engineering Contradiction:

Improvecancel performanceVSAvoidhydraulic pressure for engagement

Core Design Contradiction:

ReliabilityVSStress or pressure

Solution Approach 1:

The invention changes the parameters of the centrifugal hydraulic pressure cancellation chambers by providing independent oil supply recessed portions for each chamber. This allows optimization of the chamber volume, oil supply pathways, and pressure distribution characteristics, improving cancel performance without requiring increased return spring rigidity or engagement hydraulic pressure.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If the hydraulic pressure for clutch engagement is enhanced to compensate for insufficient cancel performance, then the cancel performance is improved, but the fuel efficiency deteriorates

Engineering Contradiction:

Improvecancel performanceVSAvoidfuel efficiency

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

By segmenting the oil supply system into independent first and second cancellation chamber recessed portions, each clutch's cancellation chamber can be optimized independently. This ensures adequate cancel performance for both clutches without requiring excessive hydraulic pressure, thereby maintaining fuel efficiency.

Inventive Principle:

Principle #1Segmentation

4Ease of operation

If a single cancellation chamber oil passage is used for both clutches, then the device complexity is reduced, but the oil supply control for each clutch is insufficient

Engineering Contradiction:

Improveindependent oil supply controlVSAvoidcomplexity of oil passage structure

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The oil passage system is segmented into a first cancellation chamber oil passage and a second cancellation chamber oil passage. The first passage supplies oil to the first centrifugal hydraulic pressure cancellation chamber, while the second passage supplies oil to the second chamber. This segmentation enables independent oil supply control for each clutch while keeping the overall structure manageable.

Inventive Principle:

Principle #1Segmentation

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

This configuration enhances the degree of freedom in adjusting the cancellation performance for both clutches, reducing the hydraulic pressure required and thereby improving fuel efficiency and vehicle performance.

Implementation Method 1

a first centrifugal hydraulic pressure cancellation chamber configured to cancel a centrifugal hydraulic pressure generated in the first engagement oil chamber, and a second centrifugal hydraulic pressure cancellation chamber configured to cancel a centrifugal hydraulic pressure generated in the second engagement oil chamber

Methodology Applied

Scientific EffectCentrifugal hydraulic pressure: Centrifugal Force

Data Source

PatentUS10174795B2Speed change device

Publication Date: 2019.01.08 AISIN AW CO LTD

AI summary

A speed change device that includes a first clutch that has a first piston, a first engagement oil chamber, and a first centrifugal hydraulic pressure cancellation chamber configured to cancel a centrifugal hydraulic pressure generated in the first engagement oil chamber; a second clutch that has a second piston, a second engagement oil chamber, and a second centrifugal hydraulic pressure cancellation chamber configured to cancel a centrifugal hydraulic pressure generated in the second engagement oil chamber and that is disposed around the first clutch; and a drum member that defines the first engagement oil chamber together with the first piston and that defines the second engagement oil chamber together with the second piston.