Glow Plug Heater With Inclined Heating Element
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ceramic heaters for glow plugs experience reduced durability due to high thermal stress caused by rapid temperature increases, which result from high current flow and localized heat generation.
Innovation Solution
A heater design featuring an insulating ceramic base with a heating element and lead buried within, where the heating element is inclined relative to the lead, reducing thermal stress by managing thermal expansion and heat distribution, and using materials like silicon nitride and tungsten carbide to match thermal expansion coefficients.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If high current is applied to the heating element to increase temperature rapidly, then the heating speed is improved, but local thermal stress increases and durability decreases
Solution Approach 1:
The heating element is designed with non-uniform cross-sectional area along its length, creating different local resistances. This causes the current to generate heat differently at various positions, preventing localized overheating and thermal stress concentration while maintaining overall heating effectiveness
Solution Approach 2:
The cross-sectional area parameter of the heating element is varied along its length rather than being uniform. This parameter change creates a resistance gradient that distributes heat generation more evenly, allowing high current application without causing localized thermal stress that would reduce durability
2Temperature
If high current flows through the heating element to achieve rapid heating, then the temperature increase speed is improved, but thermal expansion stress increases and durability decreases
Solution Approach 1:
The heating element features varying local properties along its length, with different cross-sectional areas creating distinct thermal characteristics at different positions. This prevents uniform heat concentration and reduces thermal expansion stress that would otherwise compromise structural strength and durability
Solution Approach 2:
The non-uniform cross-sectional design anticipates and prevents thermal stress concentration before it occurs. By creating intentional variations in heat generation along the element, the design cushions against the development of excessive thermal stress that would reduce durability under rapid heating conditions
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 design effectively reduces thermal stress and improves durability by evenly distributing heat and minimizing temperature differences between the heating element and insulating base, enhancing the heater's reliability and performance.
Implementation Method 1
a heating element 3 and a lead 4 which are buried in the insulating base 2. The heating element 3 is inclined relative to the lead 4
Implementation Method 2
using materials like silicon nitride and tungsten carbide to match thermal expansion coefficients
Data Source
Figure 1(a)~1(b)
Figure 2(a)~2(b)
Figure 3~4
AI summary
Disclosed is a heater including: an insulating base; a heating element buried in the insulating base and formed of a first linear section, a second linear section provided in parallel with the first linear section, and a folded section configured to connect the first linear section and the second linear section; a first lead buried in the insulating base and connected to the first linear section; and a second lead buried in the insulating base and connected to the second linear section. The first linear section is inclined relative to the first lead.