Piston Pin Assembly with Eccentric Sleeve for Variable Compression
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Solution Overview
Problem
Existing solutions for dynamically adjusting the compression ratio in internal combustion piston engines are complex and unreliable, lacking a simple and well-controllable mechanism for varying the compression ratio during engine operation.
Innovation Solution
A piston pin assembly with a rotatable eccentric sleeve and a mechanism that includes radially extending through-holes and a hydraulically operated actuator, allowing for the offset of central axes and controlled change in compression ratio through rotational movement of the connecting rod and piston pin, enabling adjustable compression settings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If an eccentric bushing with locking mechanisms is used to adjust compression ratio, then variable compression ratio is achieved, but device complexity increases
Solution Approach 1:
The invention extracts and eliminates the complex locking mechanisms, stop discs, and guide grooves from the system. Instead of using an eccentric bushing with multiple locking components, the patent uses a simple pinned hole arrangement where pins can be inserted into holes at different angular positions to achieve variable compression ratio without any locking mechanisms.
Solution Approach 2:
The invention segments the adjustment mechanism into discrete pinned positions rather than continuous adjustment. The connecting rod has multiple holes at specific angular positions, and pins are inserted into selected holes to achieve different compression ratios, simplifying the mechanism into basic geometric elements without complex interlocking components.
2Stability of the object's composition
If multiple stop discs and lock holes are provided for position retention, then position stability is improved, but manufacturing precision requirements increase
Solution Approach 1:
The invention removes the stop discs and lock holes entirely, replacing them with a simpler system where pins are inserted directly into pre-drilled holes in the connecting rod. This eliminates the need for precise alignment between multiple components and reduces manufacturing complexity while maintaining position stability through the pinned configuration.
3Ease of operation
If a guide groove is formed in the eccentric bearing for smooth lock pin entry, then ease of operation is improved, but device complexity increases
Solution Approach 1:
The invention eliminates the guide groove and eccentric bearing structure entirely. Instead, pins are simply inserted into holes drilled at specific angular positions in the connecting rod, achieving the same functional result without adding structural complexity or requiring guided movement paths.
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 solution provides a simple, reliable, and controllable method to adjust compression ratio, optimizing engine performance for dual fuel operation and reducing knocking limits when switching between liquid and gaseous fuels, while minimizing engine load and operational complexity.
Implementation Method 1
a hydraulically operated actuator, allowing for the offset of central axes and controlled change in compression ratio through rotational movement
Data Source
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AI summary
Invention relates toa piston pinassembly for an internal combustion piston engine, in which piston pinassembly the first and the second ends(14.1, 14.2)having a common first central axis(14.4)and the center area having a second central axis (14.6) which axes are offset at a distance from each other. The assembly comprises a mechanism which includes at least a first setting and a second setting, in which first setting the mechanism locks the position of the second central axis (14.4)in respect to the first central axis and in which second setting the mechanism actuates a change in the position of the second central axis in respect to the first central axis when in use and assembled to a cranking or operating internal combustion piston engine.