Cylinder Compression Ratio Adaptation via Cuff-Ring Selection

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Solution Overview

Problem

Internal combustion engines often experience deviations in cylinder compression ratios due to manufacturing and mounting inaccuracies, leading to suboptimal performance and efficiency, with higher actual ratios increasing load conditions and component wear.

Innovation Solution

A method involving the selection and arrangement of cuff-rings with varying inner circumferential face contours, inclinations, and surface areas to adapt the actual cylinder compression ratio by scraping deposits from the piston, allowing for volume adjustments to match a desired compression ratio.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If the cylinder compression ratio is increased to improve engine efficiency, then engine efficiency is improved, but load conditions and component wear increase

Engineering Contradiction:
Improveengine efficiencyVSAvoidcomponent wear
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The invention applies parameter changes by providing multiple cuff-rings with different volumes (varying inner circumferential face contours, inclinations, and surface areas) to adjust the cylinder compression ratio. This allows the compression ratio to be optimized for efficiency while preventing excessive load conditions that would cause component wear, effectively decoupling the trade-off between efficiency improvement and reliability degradation.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If manufacturing and mounting tolerances are reduced to achieve desired compression ratio, then compression ratio precision is improved, but manufacturing cost and complexity increase

Engineering Contradiction:
Improvecompression ratio precisionVSAvoidmanufacturing complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention segments the compression ratio adjustment function into multiple discrete cuff-rings, each with a specific volume characteristic. Instead of requiring high-precision manufacturing and mounting of a single cuff-ring, the system provides a selection of standardized cuff-rings that can be installed in sequence or individually, thereby achieving precise compression ratio control through modular selection rather than precision manufacturing.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention changes the approach from precision manufacturing to parameter selection by offering multiple cuff-rings with predetermined volume parameters. This allows the desired compression ratio to be achieved by selecting the appropriate cuff-ring from the plurality based on its volume characteristics, eliminating the need for tight manufacturing tolerances and complex mounting procedures.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If a single cuff-ring design is used for all cylinders, then device complexity is reduced, but compression ratio uniformity across cylinders deteriorates

Engineering Contradiction:
Improvecuff-ring design complexityVSAvoidcompression ratio uniformity
Core Design Contradiction:
Device complexityVSStability of the object's composition

Solution Approach 1:

The invention applies local quality by allowing different cylinders to be equipped with different cuff-rings from the plurality, each selected according to the specific compression ratio requirements of that cylinder. This enables each cylinder to have locally optimized compression ratio characteristics while using the same standardized cuff-ring designs, achieving uniformity across cylinders without requiring unique custom designs for each one.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention achieves universality by creating a plurality of standardized cuff-ring designs that can be applied across multiple cylinders. Instead of requiring unique custom designs for each cylinder, the same set of cuff-ring patterns can be universally used throughout the engine, with each cylinder receiving the appropriate type from the standardized set, thereby simplifying manufacturing while maintaining compression ratio uniformity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 approach enables individual adaptation of cylinder compression ratios to reduce deviations, ensuring optimal engine performance and uniform load conditions across cylinders, thereby extending component lifespan and improving efficiency.

Implementation Method 1

a scraping edge section configured for contacting deposits on an outer circumferential face of the piston during operation of the internal combustion engine

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3075997B1Adaption of cylinder compression ratio
Publication Date: 2021.06.02 CATERPILLAR ENERGY SOLUTIONS
  • EP3075997B1 patent drawingFigure 1
  • EP3075997B1 patent drawingFigure 2
  • EP3075997B1 patent drawingFigure 3A~3D

AI summary

The present disclosure relates to a method for adapting a cylinder compression ratio and a related internal combustion engine (1). The method includes determining a deviation between a value indicative of a desired cylinder compression ratio and a respective value indicative of an actual cylinder compression ratio of a piston (3) arranged in a cylinder (2). Further, a cuff-ring (22) is selected to provide a volume to adapt the actual cylinder compression ratio to reduce the deviation. By reducing the deviation, the internal combustion engine (1) is operable with a cylinder compression ratio that is closer to the desired cylinder compression ratio than before selecting the cuff-ring (22).