Variable Phase Mechanism for Camshaft Timing Control

Solution Overview

Problem

Existing variable phase mechanisms for camshafts are complex and costly due to the need for two fully independent phasing systems, which increases the complexity of components and reduces flexibility in valve timing.

Innovation Solution

A simplified variable phase mechanism that uses a drive member, first and second driven members, and a yoke with a radially outwards facing surface to vary the phase of rotation, where the yoke's transverse movement is controlled by interaction with the drive member and first driven member, reducing component complexity and allowing single-actuator control of both inner and outer camshaft timing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If two fully independent phasing systems are used to control inner and outer camshaft timing, then valve timing flexibility is achieved, but device complexity and cost increase

Engineering Contradiction:

Improvevalve timing flexibilityVSAvoidcomplexity of components

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines two independent phasing systems into a single integrated phaser assembly that simultaneously controls both inner and outer camshaft timing. The phaser includes a drive member, first driven member (inner camshaft), and second driven member (outer camshaft) with a yoke mechanism that allows both camshafts to be phased relative to the drive member using one actuator system, thereby reducing component complexity while maintaining valve timing flexibility

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The single phaser assembly performs multiple functions: it phases the inner camshaft relative to the drive member, phases the outer camshaft relative to the drive member, and enables coordinated control of both camshafts through one actuator system. This multi-functional design eliminates the need for separate phasing systems while preserving the ability to adjust valve timing for both intake and exhaust camshafts

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If two fully independent phasing systems are used to control inner and outer camshaft timing, then valve timing flexibility is achieved, but cost increases

Engineering Contradiction:

Improvevalve timing flexibilityVSAvoidcost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent combines two independent phasing systems into a single integrated phaser assembly that simultaneously controls both inner and outer camshaft timing. The phaser includes a drive member, first driven member (inner camshaft), and second driven member (outer camshaft) with a yoke mechanism that allows both camshafts to be phased relative to the drive member using one actuator system, thereby reducing component complexity while maintaining valve timing flexibility

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The single phaser assembly performs multiple functions: it phases the inner camshaft relative to the drive member, phases the outer camshaft relative to the drive member, and enables coordinated control of both camshafts through one actuator system. This multi-functional design eliminates the need for separate phasing systems while preserving the ability to adjust valve timing for both intake and exhaust camshafts

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Device complexity

If a single actuator system is used to control both inner and outer camshaft timing, then device complexity is reduced, but control precision may be compromised

Engineering Contradiction:

Improvecomplexity of componentsVSAvoidtiming control precision

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The phaser assembly segments the control function by providing independent phase adjustment mechanisms for both camshafts within the single phaser unit. The first driven member and second driven member can be independently positioned relative to the drive member through the yoke mechanism, allowing precise timing control for each camshaft while maintaining overall system simplicity

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The yoke acts as an intermediary mechanism that translates the motion from the single actuator system into independent phase adjustments for both camshafts. The yoke's geometric configuration and its interaction with the drive member and driven members enable precise timing control while maintaining the benefits of a single actuator system

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentEP2044297B1Variable phase mechanism

Publication Date: 2012.12.19 MECHADYNE LTD

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AI summary

A variable phase mechanism (110) is described which comprises a drive member (112) rotatable about an axis, first and second driven members (118, 124) rotatable in synchronism with the drive member (112), means (120, 122) for rotating the first driven member (124) relative to the drive member (112) to vary the phase of rotation of the first driven member (124) relative to the drive member (112), and a yoke (128) coupling the second driven member (118) for rotation with one of the drive member (112) and the first driven member (124) and movable transversely relative to the axis of the drive member (112) to vary the phase of rotation of the second driven member (118) relative to the drive member (112). In the invention, transverse movement of the yoke (128) is effected by means of interaction between the other of the drive member (112) and the first driven member (124) and a radially outwards facing surface defined by the yoke (128).