Temperature Determination Device Using Ambient Sensor Compensation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Temperature determination devices face systematic measurement errors due to the influence of ambient temperature on surface temperature sensors, which measure a mixed temperature between the medium and ambient temperatures, rather than the actual medium temperature.

Innovation Solution

Incorporating both surface and ambient temperature sensors with a computing unit using an approximation formula that accounts for the thermal relationship between these temperatures, allowing for the calculation of an accurate medium temperature by storing calibration values and using them to linearly interpolate or extrapolate the medium temperature from measured mixed and ambient temperatures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a surface temperature sensor is used to measure medium temperature, then the measurement is non-invasive and simple, but the measurement precision deteriorates due to ambient temperature influence

Engineering Contradiction:
Improvenon-invasive measurementVSAvoidtemperature measurement accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent introduces an ambient temperature sensor as an intermediary measurement element that indirectly captures the environmental temperature influence. By measuring the ambient temperature separately and using it as a correction parameter in the approximation formula, the system compensates for the thermal interference without requiring direct contact between the surface sensor and the medium, thus maintaining non-invasive operation while improving precision.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the measurement parameters by not only measuring the surface temperature but also measuring the ambient temperature. These two parameters are then combined through an approximation formula that accounts for the thermal relationship between them. This parameter expansion allows the system to distinguish between temperature changes caused by the medium versus those caused by ambient conditions, thereby improving measurement accuracy.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If an approximation formula with calibration factors is used, then the measurement precision improves, but the device complexity increases due to additional sensors and computing requirements

Engineering Contradiction:
Improvetemperature measurement accuracyVSAvoidsystem structure complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The computing unit performs multiple functions: it stores the approximation formula, processes surface temperature measurements, processes ambient temperature measurements, and calculates corrected medium temperatures. By consolidating these functions into a single computing unit rather than using separate dedicated devices for each function, the patent reduces overall system complexity while maintaining the precision benefits of the approximation formula approach.

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

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 approach effectively minimizes systematic errors by providing precise predictions of medium temperature, even when the mixed temperature equals the ambient temperature, ensuring accurate measurements by accounting for thermal properties and calibration factors.

Implementation Method 1

the surface temperature sensor interacts thermally not only with the surface but also with its environment

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

the surface temperature sensor does not measure the temperature of the medium or the surface in practice, but rather a mixed temperature that lies between the temperature of the medium and the ambient temperature

Methodology Applied
Scientific EffectThermal convection: Convection

Implementation Method 3

an ambient temperature sensor arranged in the area surrounding the surface, for measuring an ambient temperature

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 4

the approximation formula being the sum of the mixed temperature and a product of two factors, with the first factor resulting from the difference between the mixed temperature and the ambient temperature

Methodology Applied
Scientific EffectLinear interpolation:

Data Source

PatentEP3446086B1Temperature-determining device and method for calibrating same and for determining a medium temperature
Publication Date: 2023.06.21 ABB (SCHWEIZ) AG
  • EP3446086B1 patent drawingFigure 1
  • EP3446086B1 patent drawingFigure 2~3

AI summary

The invention relates to a temperature-determining device (19) for determining a medium temperature (9) (TMED), comprising an ambient temperature sensor (7) which is arranged in the surroundings (6) of the surface (1) for measuring an ambient temperature (8) (TU), a surface temperature sensor (4) which lies on the surface (1) surrounding the medium for measuring a mixed temperature (3) (TM) lying between the medium temperature (9) (TMED) and the ambient temperature (8) (TU), and a calculating unit (10) with an approximation formula (16) electronically stored therein. The approximation formula (16) provides a medium temperature approximation (11) (TMEDN) and is stored as the sum of the mixed temperature (3) (TM) and the product of two factors, the first factor resulting from the difference between the mixed temperature (3) (TM) and the ambient temperature (8) (TU) and the second factor resulting from the ratio of a dividend to a quotient. The dividend results from the difference between a calibration medium temperature (13) (TMEDKAL) and a calibration mixed temperature (15) (TMKAL), and the divisor results from the difference between the calibration mixed temperature (15) (TMKAL) and a calibration ambient temperature (14) (TUKAL). The invention further relates to a method for calibrating (12) a temperature-determining device (1) and to a method for determining a medium temperature (9) (TMDE).