Heater Wire Branch Line Design for Accurate Temperature Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional heater devices mounted in vehicles face a challenge in accurately detecting temperature due to a significant difference between the temperature of the heater wire and the temperature detection element, leading to reduced response speed in temperature control, and increasing the resistance of the heater wire to address this issue is not feasible as it slows down heating.

Innovation Solution

The heater device incorporates an insulating base material with a heater wire, a temperature detection element, and a branch line that extends around the temperature detection element, allowing heat from the heater wire to be transmitted to the branch line and thus reducing the temperature difference between the heating surface and the detection element without increasing the total length of the heater wire.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the heater wire is extended to surround the temperature detection element, then the temperature detection accuracy is improved, but the resistance of the heater wire increases

Engineering Contradiction:

Improvetemperature detection accuracyVSAvoidheater wire resistance

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The heater wire is divided into a main line and a branch line. The branch line extends around the temperature detection element to improve temperature detection accuracy, while the main line maintains low resistance for efficient heating. This segmentation allows different portions of the heater wire to serve different functions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The branch line is specifically positioned around the temperature detection element to locally improve temperature detection accuracy in that critical area, while the rest of the heater wire (main line) maintains its primary heating function with low resistance. This local quality enhancement resolves the contradiction by applying the extended configuration only where needed.

Inventive Principle:

Principle #3Local quality

2Measurement precision

If the resistance of the heater wire is increased to improve temperature detection, then the temperature detection accuracy improves, but the heating speed decreases

Engineering Contradiction:

Improvetemperature detection accuracyVSAvoidheating speed

Core Design Contradiction:

Measurement precisionVSSpeed

Solution Approach 1:

The heater wire is segmented into main line and branch line configurations. The main line maintains low resistance to ensure fast heating speed, while the branch line provides the extended path around the temperature detection element for accurate temperature sensing, thus resolving the contradiction between heating speed and temperature detection accuracy.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The extended configuration is applied locally only to the branch line surrounding the temperature detection element, while the main heating line maintains its original low-resistance properties. This ensures that heating speed is not compromised while achieving improved temperature detection accuracy in the critical sensing area.

Inventive Principle:

Principle #3Local quality

3Measurement precision

If the total length of the heater wire is increased to improve temperature detection, then the temperature detection accuracy improves, but the response speed of temperature control decreases

Engineering Contradiction:

Improvetemperature detection accuracyVSAvoidresponse speed of temperature control

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The heater wire is segmented into main line and branch line. The branch line is specifically extended around the temperature detection element to improve temperature detection accuracy, while the main line keeps the total heating path short to maintain fast temperature control response speed. This segmentation resolves the contradiction by minimizing the length increase only where needed for sensing.

Inventive Principle:

Principle #1Segmentation

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 configuration enhances the accuracy of temperature detection and improves the response speed of temperature control while maintaining a low resistance value for the heater wire, preventing a decrease in the rate of temperature increase when energized.

Implementation Method 1

a heater wire (11), forms a path through which current flows when energized, and generates heat when energized

Methodology Applied

Scientific EffectJoule heating: Joule Heating

Implementation Method 2

allowing heat from the heater wire to be transmitted to the branch line and thus reducing the temperature difference between the heating surface and the detection element

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS20230382190A1Heater device

Publication Date: 2023.11.30 DENSO CORP

AI summary

A heater device includes an insulating base material, a heater wire, a temperature detection element, a line and a branch line. The heater wire is provided on the insulating base material, forms a path through which current flows when energized, and generates heat when energized. The temperature detection element is provided on the insulating base material and has an electrical characteristics that change according to temperature. The line is provided on the insulating base material and is electrically connected to the temperature detection element. The branch line is provided on the insulating base material, has one end connected to the heater wire and the other end not connected to the heater wire, and extends around the temperature detection element.