US 4,364,676 AGranted

Heat transfer meter

AssigneeMemoteknik AB

InventorsViktor Oja, Sigvard Wikstrom

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Abstract

The invention relates to a portable, battery-driven device for measuring heat transfer coefficients (k-values). It uses an amplifier (1), which forms the quotient between the inner temperature minus the inner wall temperature on one hand and the inner temperature minus the outer temperature on the other hand. The temperature values of the first-mentioned substraction are obtained by thermal elements (7, 8), which are connected to the device. The difference according to the second one of the substractions is adjustable connected in a feed back circuit of the amplifier (1). The output quantity of the latter is supplied to an instrument (3) graduated in k-value. The thermal element for the measuring of the inner wall temperature can be provided at the tip of a probe (9), and may consequently be conveniently applied to different places of a wall to be investigated.

Claims9

Dependent claims

A device for measuring a heat transmission coefficient for a wall portion separating an inner media having a temperature t.sub.i and an outer media having a temperature t.sub.u, comprising:

an amplifier having an input and an output;
an indicator coupled to said output for indicating the measured heat transfer coefficient;
first thermal sensor means adapted for sensing a temperature t.sub.v of said wall portion at a surface thereof on its inner media side;
second thermal sensor means for sensing said temperature t.sub.i of said inner media, said first and second thermal sensors being connected by an input circuit coupled to said amplifier input to provide a signal proportional to (t.sub.i -t.sub.v);
and
feedback circuit means coupled at least in part from said output to said input, said circuit being adjustable to provide a feedback signal to said input for causing the gain of said amplifier to be proportional to 1/(t.sub.i -t.sub.u), whereby there is developed at said output a signal proportional to A(t.sub.i -t.sub.v)/(t.sub.i -t.sub.u) indicative of said heat transmission coefficient, where A is a constant selected for calibrating said indicator to a predetermined scale.

3 more elements

Dependencies are inferred from the claim text.