Air Conditioner Rotating Infrared Sensor for Self-Heat Compensation

Solution Overview

Problem

Existing air-conditioning apparatuses with infrared sensors struggle to accurately detect temperature changes in air-conditioned spaces due to the sensors' self-generated heat, which affects the precision of temperature detection.

Innovation Solution

An air-conditioning apparatus with a heat-source detection unit featuring a rotating infrared sensor that exposes only the necessary part to the air-conditioned space while concealing it when not in use, allowing for compensation of self-generated heat in temperature readings.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a highly sensitive infrared sensor is used to detect temperature changes in the air-conditioned space, then the detection precision of air temperature is improved, but the sensor's self-generated heat affects the temperature detection accuracy

Engineering Contradiction:

Improveair temperature detection precisionVSAvoidsensor self-generated heat

Core Design Contradiction:

Measurement precisionVSObject-generated harmful factors

Solution Approach 1:

The infrared sensor detection function is segmented into two distinct operational modes: air temperature detection mode and sensor self-heat detection mode. The rotating cover physically separates these two detection targets, allowing the sensor to alternately measure air temperature and its own self-generated heat without interference from the other measurement.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The rotating cover implements periodic action by alternately exposing the infrared sensor to the air-conditioned space and concealing it to detect self-heat. This periodic switching between external temperature detection and self-heat detection enables the system to collect both types of data sequentially, then compensate for self-heat effects in the air temperature measurements.

Inventive Principle:

Principle #19Periodic action

2Measurement precision

If the infrared sensor is continuously exposed to the air-conditioned space for temperature detection, then the temperature detection function is maintained, but the sensor's self-generated heat continuously interferes with the measurement

Engineering Contradiction:

Improvetemperature detection accuracyVSAvoiddetection reliability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The rotating cover implements periodic action by alternately exposing the infrared sensor to the air-conditioned space and concealing it to detect self-heat. This periodic switching between external temperature detection and self-heat detection enables the system to collect both types of data sequentially, then compensate for self-heat effects in the air temperature measurements.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The system uses feedback by measuring the sensor's self-generated heat in a controlled state (when concealed) and then using this self-heat value to compensate for temperature readings taken when the sensor is exposed. This feedback mechanism continuously corrects the air temperature detection accuracy by subtracting the measured self-heat component.

Inventive Principle:

Principle #23Feedback

3Measurement precision

If the infrared sensor is concealed to detect self-generated heat, then the self-heat measurement is achieved, but the sensor cannot simultaneously detect air temperature

Engineering Contradiction:

Improveself-heat detection accuracyVSAvoiddetection time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The rotating cover implements periodic action by alternately exposing the infrared sensor to the air-conditioned space and concealing it to detect self-heat. This periodic switching between external temperature detection and self-heat detection enables the system to collect both types of data sequentially, then compensate for self-heat effects in the air temperature measurements.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The system performs preliminary action by first measuring the sensor's self-generated heat when concealed, then using this pre-obtained self-heat value to compensate for subsequent air temperature measurements. This preliminary measurement of self-heat allows for accurate correction of temperature readings without requiring simultaneous measurement of both parameters.

Inventive Principle:

Principle #10Preliminary action

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 design enhances the versatility and accuracy of temperature detection by isolating the sensor's self-generated heat, enabling effective air-conditioning control despite the sensor's self-heating characteristics.

Implementation Method 1

an infrared sensor that detects a heat source in an air-conditioned space

Methodology Applied

Scientific EffectInfrared radiation detection: Infrared Radiation

Data Source

PatentUS11994315B2Air-conditioning apparatus

Publication Date: 2024.05.28 MITSUBISHI ELECTRIC CORP

AI summary

An air-conditioning apparatus includes a heat-source detection unit provided at the front of a housing. The heat-source detection unit includes an infrared sensor that detects a heat source in an air-conditioned space and a supporting member that supports the infrared sensor. The supporting member is rotated about an axis that extends in a vertical direction. Part of the infrared sensor that corresponds to the field of view thereof is exposed when the infrared sensor faces the air-conditioned space, and the part of the infrared sensor is concealed when the infrared sensor does not face the air-conditioned space.