JPS5876731A - Temperature measuring device - Google Patents

Abstract

PURPOSE:To make it possible to measure the temperature of a material to be measured accurately in a short time, by detecting the difference in temperature between the material to be measured and a temperature detector from the changing rate with time of the output from the temperature detector. CONSTITUTION:A measurement starting command is given at a time T1 when the temperature detector 10 is contacted with or immersed in the material to be measured. The output of the detector 10 is written in a sample and hold circuit 11 at a time T2. The output of the detector 10 is written in a sample and hold circuit 12 at a time T3. The deivation of each stored temperature in the circuits 11 and 12 is computed and the difference in the temperatures of the material to be measured W and the detector 10 at the time T3 is computed by multiplying a constant. The output of the circuit 12 and the temperature difference data from the circuit 17 are added 18. The added output is transferred to a sample and hold circuit in response to the signal of a timer 16. After the A/D conversion 21, the result is displayed 22 as the temperature of the material to be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature measuring device in which humidity detection Jr'j is determined by contacting or immersing the object to be measured only in measurement 1 [3] to determine the humidity of the object to be measured. I-ru.

A general temperature sensor has a heat capacity 111 of 11 to some extent, and before measurement there is a temperature difference between the temperature sensor and the object to be measured. If a certain amount of time does not pass even if you touch or immerse yourself in the temperature sensor, the temperature detector's 1111i If +: J i skin measurement -1! The temperature of the object is not the same, and before the 411i degrees of both are turned, the output of Wlltll altitude is detected and 4111 degrees is changed to 1.
When li11 is constant, a difference 1ill+constant+jl;j will occur corresponding to the temperature difference between the two.

Therefore, in the conventional device, the iIW degree of the object is measured by waiting until the n111 degrees of the image are the same, and then detecting the output of t9. However, in this way, -4゛d broke the 7!11 W detector! 11 After contacting or immersing in a fixed object, l'll
There was a problem in that it took a long time to complete the l'1 degree 7111I determination, making it impossible to measure the temperature in a short time.

The present invention has been made in consideration of the points j, lr, and i between the conventional methods, and the magnitude of the rate of change over time in the temperature detector output is determined by the temperature difference between the object to be measured and the temperature detector. The humidity difference between the measured object and the temperature sensor is detected from the rate of change in the temperature sensor output over time, and the humidity difference between the measured object and the temperature sensor is calculated based on both this and the temperature sensor output. The temperature of the object is calculated, thereby making it possible to accurately measure the temperature of the object even when there is a temperature difference between the object and the temperature detector.

First, the measurement principle of the temperature measuring device according to the present invention will be explained based on FIGS. 1 and 2.
The figure is a graph showing the change in the temperature Or of the temperature sensor after the temperature sensor is in contact with or immersed in the object to be measured at time To, and as shown in Figure 1, the temperature θW of the object to be measured is If it is relatively low, the temperature of the humidity detector or
As shown in Figure 2, when the temperature of the object to be measured θW is high, the rate of increase in the temperature sensor temperature θr becomes faster, and as a result of experiments, the temperature of the temperature sensor Or increases. It has been found that the speed is approximately proportional to the magnitude of the temperature difference between the object to be measured and the temperature sensor. shi/kogatte, n11)
After touching or immersing the temperature detector into the object to be measured, detect the rate of increase in temperature Or of the temperature sensor, calculate the temperature difference θd between the object to be measured and the temperature sensor from this, and calculate the temperature difference θd between the object and the temperature sensor. If you add the temperature O1 of the device and the temperature sensor, I'! Even if there is a difference of 4 in ll', the temperature of the object to be measured can be measured by 47rrIf.

-1-min of the temperature sensor temperature or It can be detected by measuring how much the output has changed in a fixed unit 11, and how much it has changed during the r interval Δ, and then a predetermined constant K is added to this.
By multiplying , 4111 degree difference 04 complete table ゎ14'' data can be calculated.

Next, consider the above measurement principle. IiA degree i1+11
An embodiment in which >i2 is performed will be explained based on the drawings-4-. In FIG. 3, ]0 is the sense of the thermistor etc. 1t1i! It is a temperature sensor with a built-in element, and is
l! If the treasure W is solid, break the temperature detector 1111.
If the treasure W to be measured is a liquid, the entire temperature detector 10 is immersed in the object W to be measured.

1.1. , :L2 is a sample bold circuit that reads and holds the signal output from the temperature sensor 1o at a predetermined timing, and the sample hold circuit 1] is a sample bold circuit that reads and holds the signal output from the temperature sensor 1o at a predetermined timing. A timer that is deenergized by pressing the measurement start command switch SW that is pressed immediately after, and times out after a certain period of time]-3
The sample and hold circuit 12 is activated in response to the time-up signal of timer 3, and is activated in response to the time-up signal of timer 5, which times up after a certain unit time Δ. It looks like this.

As shown in FIG. 1, the predetermined time tn is set to approximately the ratio of Σ to the time t6 required for the temperatures of both objects to become equal (σ) after the temperature detector 10 is brought into contact with or immersed in the object W to be measured. The unit time Δt is a time sufficiently shorter than the fixed time tn, for example, 0. It is set to about 10 seconds.

Therefore, as shown in FIG. 1 or FIG. 2, it is assumed that the measurement start command is received at time T]- immediately after the temperature measuring device 10 touches the object to be measured WKJ'ij, and bL< is immersed in the object WKJ'ij. Then, constant lI & 1f from this time T]
Temperature 1σ detection company 1 at time T2 when flt O has elapsed
Output J of No. 1G is the temperature of temperature detector 1o at time T2 as 0]-→Non-pull hold circuit]-1 is read 1
R7i 1-n l/) The temperature sensor at time 11 when a unit time Δt has elapsed from this time, the output of 〇 is output from the temperature sensor at time T3. 12, it will be read J5.

On the other hand, 17 is the temperature sensor stored in the sample hole circuit 11.1.2] 1111 degrees (h) of 0, the deviation △θ of 02 is calculated, this is multiplied by the constant K, and the temperature is turned on at 115 increments T3. 5 Humidity difference O between measured object W and temperature sensor] 0
It is a temperature difference calculation circuit that calculates d, and the constant I (is
Length of unit time △t, temperature sensor] 0 heat capacity f + t 4
．． 71: Temperature calculated by a constant determined by 1;!
') The data Od is equal to the actual temperature difference at the 113th interval T3': determined experimentally.

Roughly speaking, 18 is the output θ2 of the sample bold circuit 2.
and temperature difference data θ output from the temperature difference calculation circuit 17
d and the temperature θ of the object W at time T3.
The output value of this adder circuit]8 is transferred to the sample and hold circuit 20 in response to the time-up signal KI6 of the timer 16 which times up a certain period after the time-up of the timer 15, and is transferred to the sample and hold circuit 20. The output value is converted into a digital quantity by the AD converter 21, and this is displayed on the display 2 as the temperature of the measured object W.
2.

In the above embodiment, a certain unit time Δ1. The temperature difference data 0d was fully calculated by setting a constant to the output change Δθ of the temperature sensor 10 between
The temperature difference data Od may be calculated by detecting the time required for the output to change by a constant value and dividing a constant by the detected time.

As described above, in the present invention, the temperature difference between the object to be measured and the temperature sensor is detected from the rate of change in the output of the temperature sensor over time, and this is combined with the output value of the temperature sensor. Since I am trying to calculate the temperature of the covered ii+o treasure,
The temperature of the measured object can be accurately measured even when there is a temperature difference between the measured object and 111 It has the advantage of being accurate in a short period of time.

It is still possible to reduce the temperature difference between the object to be measured and the temperature sensor by turning off the current to the temperature sensor and heating the sensor by 1IIlli degrees to shorten the time required for measurement completion J5. If you make it so, it will be a disaster! thing'fIi
! d measurement 11 if the temperature is lower than the temperature of the temperature sensor
However, the method of the present invention has the advantage of being able to shorten the measurement time even in such cases.

[Brief explanation of drawings]

Figures 1 and 2 are graphs showing changes in temperature sensor humidity over time based on the rllll'1 degree measurement principle of the present invention. 2 shows a case where the object to be measured is washed (high degree), and FIG. 3 is a block diagram of a dimensional wetness measuring device according to an embodiment of the present invention. 10...Temperature detection device, IJ 1.2... - ripple hold circuit, 17... humidity difference calculation circuit, ]8...
7- Adding circuit, 22...Display device, W...Measurement object. Patent applicant Toyota Machinery Co., Ltd. 8-f'l field

Claims (1)

[Claims] 0) Only when the temperature should be measured! In a temperature measuring device that measures the temperature of a measured object by touching or immersing a temperature sensor into a fixed object, the temperature sensor may emit a signal in response to contacting or immersing the temperature sensor into the object to be measured. A first detection means detects the entire output of the temperature sensor after a certain period of time has elapsed since the measurement start signal is sent, and the temperature sensor detects the temperature after the certain period of time. a second detection means for detecting a rate of change in the output of the IPI device relative to the elapsed time as a value representing a temperature difference between the object to be measured and the temperature detector; and the first detection means. A temperature measurement device @ characterized in that it is provided with calculation means for calculating the temperature of the object to be measured from the output of the temperature detector and the value representing the humidity difference detected by the second detection means.