Multipoint Ignition Device Heat Value Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multipoint ignition engines, the electrode pair temperature must be maintained within a specific range to prevent carbon deposition and pre-ignition, necessitating a method to adjust the heat value of the ignition device effectively.
Innovation Solution
A multipoint ignition device with an interposed member between the cylinder head and block, featuring intermediate members connected to electrode pairs, where the exposure area of these members can be adjusted to control the heat received from combustion gases, allowing for heat value adjustment by modifying the projection amount, width, height, or surface area of the intermediate members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the electrode pair temperature is increased to prevent carbon deposition, then carbon cleaning is improved, but pre-ignition occurs causing ignition before spark flies
Solution Approach 1:
The intermediate member is designed with non-uniform exposure to combustion gases at different locations. The exposure area is strategically controlled so that some regions receive more heat while others receive less, creating a temperature distribution that prevents both carbon deposition and pre-ignition in different areas of the electrode pair assembly
Solution Approach 2:
The heat value of the ignition device is adjusted by changing the exposure area parameter of the intermediate member to combustion gases. By modifying this geometric parameter, the temperature of the electrode pair is controlled within an optimal range that prevents carbon deposition while avoiding pre-ignition
2Object-affected harmful factors
If the electrode pair temperature is decreased to prevent pre-ignition, then pre-ignition is avoided, but carbon deposits on the electrode pair
Solution Approach 1:
Different regions of the intermediate member have different exposure areas to combustion gases, creating localized temperature zones. This ensures that the electrode pair maintains sufficient temperature in critical areas to prevent carbon deposition while keeping other areas cooler to avoid pre-ignition
Solution Approach 2:
The exposure area of the intermediate member is optimized to achieve the minimum necessary temperature for carbon prevention without exceeding the threshold that causes pre-ignition. This parameter adjustment balances both opposing requirements
3Adaptability or versatility
If the exposure area of the intermediate member is increased to reduce heat value, then heat value control is improved, but the device structure becomes more complex
Solution Approach 1:
Rather than making the entire intermediate member complex, only specific local regions are designed with varying exposure areas. This localized approach achieves heat value control functionality while minimizing overall structural complexity
Solution Approach 2:
The heat value is controlled by adjusting geometric parameters of the intermediate member such as exposure area, projection amount, width, or height. These parameter variations provide versatile heat value control without requiring fundamentally different structural designs
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 method enables precise control of the heat value, preventing carbon deposition and pre-ignition by optimizing the temperature of the electrode pairs, thereby improving engine performance and fuel efficiency.
Implementation Method 1
by adjusting the exposure area of the intermediate member, the amount of heat received by the multipoint ignition device from the combustion gas can be adjusted
Implementation Method 2
the amount of heat received by the multipoint ignition device from the combustion gas can be adjusted
Data Source
AI summary
A multipoint ignition device comprises: a head gasket (1) interposed between a cylinder head and a cylinder block of an engine, having an opening (3) in a position corresponding to a cylinder opening portion; and a plurality of intermediate members (6) connected respectively to a plurality of electrode pairs (2) and held by the head gasket (1). A part of at least one of the plurality of intermediate members (6) is exposed to the opening (3).