Valve Timing Locking Structure with Elastic Pin Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing valve timing adjustment apparatuses for internal combustion engines face challenges in reducing manufacturing costs and improving productivity due to accumulative component tolerances, particularly in the interaction between the rotor and housing components.
Innovation Solution
A locking structure for the valve timing adjustment apparatus is introduced, featuring a ratchet plate with locking grooves of varying depths and a locking pin member with elastic components, including an outer pin, inner pin, and lifter ring, which inhibits relative rotation between the rotor and housing, thereby reducing the load on components and simplifying tolerance management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional valve timing adjustment apparatus is used, then valve timing can be adjusted, but manufacturing cost increases and productivity decreases due to accumulative component tolerances
Solution Approach 1:
The locking mechanism is divided into separate functional components: a locking pin with elastic elements, a ratchet plate with locking grooves, and a lifter ring. This segmentation allows each component to be manufactured independently with standard tolerances, avoiding the need for extremely tight cumulative tolerances across the entire assembly. The elastic elements can be pre-assembled and then installed as a unit, simplifying the overall manufacturing process.
Solution Approach 2:
The elastic elements (outer pin and inner pin) act as intermediaries between the locking pin and the locking grooves. These elastic elements absorb dimensional variations and tolerance accumulations, providing a compliant connection that maintains reliable locking engagement without requiring precision machining of all mating surfaces. The lifter ring serves as an intermediary component that guides the locking pin into the locking grooves while accommodating tolerance variations.
2Manufacturing precision
If a locking structure with multiple elastic components is used, then tolerance impact is reduced, but device complexity increases
Solution Approach 1:
The locking pin member employs a nested configuration where the inner pin is positioned within the outer pin, both being elastically mounted in the same fitting hole. This nesting arrangement consolidates multiple elastic elements into a compact integrated unit, reducing the overall space required compared to separate elastic components. The nested structure maintains the tolerance benefits while minimizing the complexity increase through spatial efficiency.
Solution Approach 2:
The outer pin and inner pin are merged into a single locking pin member assembly that functions as one integrated locking unit. Both elastic elements work together in sequence to engage with the locking grooves, combining their individual tolerance-compensating functions into a unified mechanism. This merging reduces the number of separate parts that need to be manufactured and assembled, offsetting the added complexity of the multi-element design.
3Stability of the object's composition
If the rotor and housing are prevented from relative rotation, then positional change is inhibited, but the locking mechanism complexity increases
Solution Approach 1:
The locking mechanism transitions from a static locked state to a dynamic locked state. The elastic elements (outer pin and inner pin) provide a flexible, adaptive locking action that can accommodate minor positional variations while maintaining the locked state. This dynamic approach allows the rotor and housing to remain positionally stable without requiring a rigid, complex anti-rotation mechanism, as the elastic elements naturally absorb and compensate for small movements.
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 locking structure reduces manufacturing costs and improves productivity by minimizing the impact of component tolerances on the contact surfaces, allowing for smoother operation and effective valve timing adjustment without affecting the rotational phases.
Implementation Method 1
an outer pin elastically disposed in a fitting hole formed in at least one of the plurality of vanes; an inner pin elastically disposed inside the outer pin
Implementation Method 2
an outer spring applying elasticity to the locking grooves may be disposed between the second recession and a first end of the upper cap. A third recession may be formed at a first end of the inner pin, and an inner spring applying elasticity to the locking grooves may be disposed between the third recession and the first recession of the upper cap
Data Source
AI summary
The present disclosure provides a locking structure of a valve timing adjustment apparatus for an internal combustion engine, using torque from a camshaft and the pressure of working fluid. The locking structure includes an anti-rotation mechanism for inhibiting or preventing a position change between a rotor and a housing by preventing relative rotation of the rotor to the housing. The anti-rotation mechanism further includes: a plurality of locking grooves which are formed on the ratchet plate with different depths and connected to each other; and a locking pin member. In particular, the locking pin member has: a hollow outer pin elastically disposed in a fitting hole formed in vanes, an inner pin elastically disposed inside the outer pin, and a lifter ring coupled to the upper portion of the outer pin to slide on the inner side of the fitting hole.