Valve Timing Control Reducing Friction via Displacement Regulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing valve opening and closing timing control apparatuses suffer from increased frictional resistance and engagement loss due to the biasing force applied by a spring member, leading to suppressed rotational speed and deteriorated responsiveness when an electric actuator is driven.
Innovation Solution
A valve opening and closing timing control apparatus featuring a phase adjustment mechanism with a differential speed reduction mechanism, where the drive shaft is rotated by an electric actuator to set a relative rotation phase between the driving and driven side rotators, and a displacement regulation portion is used to regulate the displacement of the inner gear, reducing the engagement depth and contact surface pressures between the internal and external toothed portions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a biasing member is disposed to apply a biasing force in the direction in which the internal toothed portion and external toothed portion are engaged, then the engaged state of the ring gear and inner gear is maintained against engagement reaction force, but engagement loss increases due to strong contact between the toothed portions
Solution Approach 1:
The patent introduces a displacement regulation portion that dynamically adjusts the displacement of the inner gear in the biasing direction, changing the engagement depth parameter. By regulating the displacement to be less than the full biasing force would allow, the contact pressure between toothed portions is optimized to maintain engagement stability while reducing excessive contact and engagement loss.
2Force
If the outer periphery of the drive shaft is brought into contact with the inner periphery of the inner gear over a long area, then the biasing force is effectively applied, but frictional resistance is increased, suppressing rotational speed and deteriorating responsiveness
Solution Approach 1:
The displacement regulation portion creates a localized contact region between the drive shaft outer periphery and the inner gear inner periphery. Instead of uniform contact over a long area, the regulation portion concentrates the effective contact to a specific location, reducing the overall frictional resistance while maintaining sufficient biasing force application at the critical engagement point.
3Strength
If the biasing force is increased to maintain strong engagement, then the ring gear and inner gear remain firmly engaged, but frictional resistance increases, causing deterioration in responsiveness when the electric actuator is driven
Solution Approach 1:
The displacement regulation portion introduces dynamic adjustment capability to the engagement system. The regulation can adaptively control the displacement of the inner gear, allowing the engagement strength to be optimized for different operating conditions. This dynamic regulation maintains sufficient engagement strength while minimizing frictional resistance that would hinder actuator responsiveness.
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 reduces engagement damage, increases the durability of the biasing member, and enhances responsiveness by minimizing the biasing force and contact area, allowing for quicker engine stoppage and improved valve timing control.
Implementation Method 1
a biasing member provided on an outer periphery of the drive shaft to apply a biasing force in a direction such that the external toothed portion of the inner gear is engaged with the internal toothed portion of the ring gear
Implementation Method 2
an inner gear disposed coaxially with an eccentric axis in a posture parallel to the rotation axis such that an external toothed portion thereof is engaged with a portion of an internal toothed portion of the ring gear, and a drive shaft fitted into the inner gear, wherein the phase adjustment mechanism is configured with a differential speed reduction mechanism in which the drive shaft is rotated about the rotation axis by the driving force of the electric actuator such that the inner gear revolves around the rotation axis while spinning on the eccentric axis
Data Source
AI summary
A valve opening and closing timing control apparatus includes: a driving side rotator disposed rotatably about a rotation axis and configured to rotate synchronously with a crankshaft; a driven side rotator disposed rotatably about the rotation axis and configured to be rotatable relative to the driving side rotator and to rotate integrally with a valve opening/closing camshaft; a phase adjustment mechanism configured to set a relative rotation phase between the driving side and driven side rotators by a driving force of an electric actuator, a biasing member provided on an outer periphery of a drive shaft to apply a biasing force in a direction such that an inner gear is engaged with a ring gear; and a displacement regulation portion configured to regulate a displacement of the inner gear.