DD295415A5 - DEVICE FOR DETERMINING THERMOTOMETERES WITH SEMICONDUCTOR TEMPERATURE SENSORS - Google Patents

Abstract

The invention relates to a Meszverfahren for the determination of heat flows. The aim is to obtain a Meszanordnung that works exactly and with a low Meszaufwand. For this purpose, a plurality of semiconductor temperature sensors were mounted on a printed circuit board on the top and bottom, which were connected by suitable Leiterzuege with the power supply and Meszgroeszenverarbeitung and potted in a monolithic layer. If a heat flow flows through the layer, then the thermal states of the semiconductor temperature sensors are different, a difference signal forms which can be electronically processed and displayed. If the semiconductor temperature sensors are measured individually, in pairs and in groups, then local, differential and integral information can be obtained. Due to the high sensitivity of the semiconductor temperature sensors, a simple, accurate and practical Meszgroeszenbestimmung is possible. Fig. 1 {difference signal; Difference measurement; Semiconductor temperature sensors; Measurement; Meszwertverarbeitung; Meszwertverfaelschung; Temperature; Temperature difference; thermoelectric converters; Waermedurchlaszwiderstand; HEAT FLOW; Waermeverlust}

Description

For this 2 pages drawings

Field of application of the invention

The invention relates to a device for determining heat flows. The method can be used anywhere where heat flows occur that can be measured in a surface area.

Characteristic of the known state of the art

The heat flow Q through an area A is characterized by the amount of energy transported in the time unit. For the thermoelectric measurement of this heat flow, an additional thermal resistance R is introduced into the heat flow in the hitherto known methods and the heat flow in accordance with the temperature difference At, which can be measured with thermoelectric converters such as thermocouples and semiconductor strain gauges

calculated.

The previously known technical solutions either have a relatively low sensitivity, a high thermal resistance, so that the measured heat flow is distorted or require a high production cost, since the thermoelectric converter must be linked in complex chain circuits.

Object of the invention

The aim of the invention is to provide a measuring method that allows a sensitive and accurate determination of heat flows.

Explanation de-. Essence of the invention

The object of the invention is the measurement of the temperature differences by means of highly sensitive semiconductor temperature sensors and an easy and practical measured value processing.

According to the invention the object is achieved in that on the top and bottom of a circuit board, which has the necessary Leiteri'üge, several pairs of semiconductor temperature sensors are soldered and formed by encapsulation with a mass of high thermal conductivity, a monolithic layer.

The essence of the invention is that in the heat flow, this layer is brought with a small, the measured variable insignificant influencing thermal resistance. The temperature difference arising in this layer is a measure of the flowing heat flow and is detected by the semiconductor temperature sensors.

The semiconductor temperature sensors are interconnected via interconnects and flexible line individually, in pairs or groups with a suitable evaluation circuit.

A point, pair or group measurement of thermoelectric signals is possible, whereby local, differential and integral information can be obtained.

If the semiconductor temperature sensors on both sides of the layer are suitably selected and supplied with circuitry and adjusted, no differential current flows at the connection point of the sensors if no temperature gradient occurs in the layer. If a heat flow flows through the layer, a temperature gradient forms and the semiconductor temperature sensors have different temperatures. Depending on the switching, this results in a current or voltage difference signal at the connection point of the sensors, which can be boosted via DC voltage amplifiers and displayed with conventional devices.

The high sensitivity of the semiconductor temperature sensors allows use at low heat flows, allows the use of simple evaluation circuits and leads to high accuracies.

Ausführungsbnlsplel

Fig. 1: shows in cross section the structure of the heat flow sensor

 Fig. 2: shows the electrical supply and signal processing. ,

In the example shown in FIG. 2, five temperature-current transformers on the upper b * w. Bottom side connected in parallel.

If a temperature difference arises due to a heat flow between the upper side and the lower side, a differential current forms between the sensors which can be fed as a signal to an operational amplifier, amplified and displayed by a voltmeter or a digital LCD line. The display value resulting from the differential current represents a measure of the heat flow.

On the printed circuit board 2, pairs of high-sensitivity temperature-current transformers 4 are installed at the predetermined soldering points as semiconductor temperature sensors.

In order to achieve a good heat exchange and a low thermal resistance, the system is potted with a good heat conducting mass 3, so that a quasi-monolithic layer is formed.

Claims (2)

1. A device for measuring heat flows by means of highly sensitive semiconductor temperature sensors, characterized in that the semiconductor temperature sensors (4) mounted on a printed circuit board (2), at the top and at the bottom of a layer consisting of a potting compound with high thermal conductivity, are arranged. 2. Device according to claim 1, characterized in that the semiconductor temperature sensors are used individually, in pairs and in groups for the measurement, whereby local, differential and integral information is obtained.