Diesel Engine Piston Gap Control for Combustion Efficiency

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Solution Overview

Problem

Existing diesel engine technologies face challenges in maintaining a minimal gap between the piston and engine head across varying operating conditions, leading to inefficiencies in fuel consumption and combustion efficiency due to non-optimal clearance volumes.

Innovation Solution

Implementing a gap control system that adjusts the distance between the piston and engine head based on engine temperature, speed, and noise sensor feedback, using a look-up table to maintain the gap as close to zero, thereby minimizing clearance volume and accounting for mechanical wear.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the gap between piston and engine head is minimized to improve combustion efficiency, then fuel consumption is reduced, but the risk of collision between piston and engine head increases at high speed

Engineering Contradiction:
Improvecombustion efficiencyVSAvoidcollision risk
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent implements a dynamic gap control system that adjusts the clearance volume between piston and engine head based on real-time operating conditions. The control unit modifies the gap size according to engine speed, temperature, and load parameters, allowing the system to maintain optimal combustion efficiency at low speeds while preventing piston-head collision at high speeds. This dynamic adjustment resolves the contradiction by making the gap a variable parameter rather than a fixed dimension.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the physical parameter of clearance volume dynamically based on operating conditions. By using sensors to detect engine speed, temperature, and piston position, the control unit adjusts the gap size through actuated mechanisms (such as adjustable engine head position or variable piston rod length). This parameter change approach allows optimization of combustion efficiency when small gap is beneficial while maintaining safety margins when collision risk increases.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the gap is reduced to minimize clearance volume, then combustion efficiency improves, but mechanical wear increases leading to tolerance accumulation over time

Engineering Contradiction:
Improvecombustion efficiencyVSAvoidmechanical wear
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent incorporates a feedback mechanism where noise sensors and position sensors continuously monitor the engine operation and piston-head clearance. The control unit processes this feedback information and adjusts the gap dynamically to maintain optimal values. This feedback system compensates for mechanical wear over time by detecting changes in piston position or impact noise and automatically adjusting the clearance volume, thereby maintaining combustion efficiency despite tolerance accumulation from wear.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system performs preliminary adjustments to the gap based on predicted operating conditions and wear patterns. By proactively adjusting the clearance volume before significant wear occurs or based on pre-programmed wear compensation schedules, the system maintains optimal combustion efficiency while accounting for the inevitable accumulation of tolerances over the engine's service life.

Inventive Principle:
Principle #10Preliminary action

3Device complexity

If a fixed gap is used to simplify the system, then device complexity is reduced, but the system cannot adapt to varying operating conditions such as temperature and speed

Engineering Contradiction:
Improvecontrol system complexityVSAvoidadaptation to operating conditions
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent implements a multi-functional control system that simultaneously manages multiple parameters (engine speed, temperature, piston position, gap size) using a single integrated control unit. This universal controller adjusts the clearance volume based on combined inputs from various sensors, allowing the system to adapt to diverse operating conditions without requiring separate control mechanisms for each parameter. The look-up table approach provides pre-calculated optimal gap values for different operating scenarios, simplifying the real-time decision-making process while maintaining high adaptability.

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

Data Source

PatentEP3636903B1Cold start management system for a diesel combustion engine
Publication Date: 2021.08.25 FPT MOTORENFORSCHUNG AG
  • EP3636903B1 patent drawingFigure 1

AI summary

Cold start management system for a diesel combustion engine (E), the combustion engine comprising a cylinder, a piston (P) mounted for reciprocating movement in the cylinder, a cylinder head (H) mounted to overlie the cylinder and with the primary cylinder and a face (F) of the piston defining a combustion chamber (CH) and a surface (CR) surrounding the combustion chamber; wherein said reciprocating movement defines a gap (G) between said surface (CR) and said cylinder head (H), the system comprising minimization means to minimize said gap on the basis of an engine temperature.