JPH08136350A - Temperature distribution measuring device of temperature and system - Google Patents

Abstract

PURPOSE: To provide a two-dimensional temperature distribution measuring device capable of accurately measuring a temperature of a slit plate working as a chopper end of accurately obtaining a heat source to be measured without having a movable section such as the chopper or the like. CONSTITUTION: An infrared radiation detection means 1 is rotated to be scanned on a slit plate 2 consisting of an infrared radiation penetrating section and an infrared shading section which are substantially fixed, thereby executing temperature measuring. The slit plate 2 can be moved by a distance of a width of the infrared radiation penetrating section with the infrared radiation detection means 1 as the center.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature distribution measuring device and system using a pyroelectric sensor for detecting infrared rays, especially heat rays.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for means for measuring non-contact temperature distribution in human body detection in a room, detection of abnormal heat generation of electric equipment such as a switchboard and boiler, and temperature control of precision processing machines.

Conventionally, as a means for measuring the temperature distribution, there is a method of using a quantum type sensor, but these sensors require cooling means and the apparatus becomes large and expensive. The method using the thermal pyroelectric sensor does not require cooling and is relatively inexpensive.

In this pyroelectric sensor, a material having a pyroelectric effect is used as a pyroelectric element, and the temperature of the surface of the pyroelectric element is changed by irradiation of infrared rays, and a change in surface charge resulting from the change is measured as a sensor output. Therefore, these sensors have a general structure in which a Fresnel lens or a chopping mechanism is installed in front of the pyroelectric element.

A Fresnel lens is a combination of an infrared transmitting part and an infrared non-transmitting part.
A change in the sensor output occurs and the heat source can be detected. Therefore, a stationary heat source cannot be detected.

On the other hand, the chopping mechanism is intended to make infrared rays intermittently incident, and is also capable of detecting a stationary heat source. For this mechanism, various mechanisms such as a shutter type, a lever type, a disc type, and a cylinder type of a camera have been developed, but actuators such as motors and solenoids are all required, and reliability is a problem. Also, it is difficult to measure the temperature of this part, which is the reference temperature,
The measurement temperature accuracy was lower than that of thermopile.

[0007]

As described above, the conventional method has a complicated structure because the chopper is used for detecting the static heat source. Further, since it is difficult to measure the temperature of the chopper, which is the reference temperature in the temperature measurement of the object, it is common to measure the temperature of a portion similar to this to obtain the chopper temperature. Therefore, there is a problem that the accuracy of the temperature is low.

An object of the present invention is to provide a temperature distribution measuring device and system capable of accurately measuring temperature with a simple structure in consideration of such problems of conventional temperature measurement.

[0009]

According to the present invention, there are provided a slit plate having at least one pair of an infrared transmitting portion and an infrared shielding portion, an infrared detecting means arranged behind the slit plate, and the infrared detecting means. A temperature distribution measuring device, comprising: rotating means for rotating and scanning.

[0010]

According to the present invention, with the above-described structure, by rotating and scanning the pyroelectric sensor with respect to the slit plate composed of the infrared transmitting portion and the infrared shielding portion, it is possible to detect a stationary heat source without having a movable portion such as a chopper. It is possible to measure the temperature distribution in the space.

Further, since the temperature of the slit plate acting as the chopper can be accurately measured, the temperature of the heat source to be measured can be accurately obtained.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 shows a schematic configuration of a temperature distribution measuring apparatus according to one embodiment of the present invention. The infrared sensor 1 of the pyroelectric type rotates left and right around a rotating shaft 8, and a slit plate 2 having a transmitting part for transmitting infrared rays and a shielding part for shielding infrared rays is provided on the front surface of the infrared sensor. It is provided in a cylindrical shape centering on. When the infrared sensor 1 is rotated about the rotating shaft 8, when an object having a radiation temperature different from the radiation temperature of the slit plate 2 is faced, a sensor output corresponding to the temperature difference between the slit plate 2 and the object is obtained.

FIG. 2 shows a person 21 standing in front of the sensor 1.
An operation time chart in the case of measuring is shown. As the motor starts rotating, a sensor output corresponding to the temperature difference between the facing visual field and the slit plate 2 is generated. Human body 21 in advance
Measure the sensor output threshold that matches the temperature difference between
If an output above that value is observed, the comparator output should be triggered. It can be seen that the heat source exists in the direction facing any of the transmission parts of the slit plate 2 when the time taken for the trigger from the start of rotation of the motor is obtained. In this case, it can be seen that a person was present in the direction facing the fifth transmissive portion counting from the position when the motor was started. (Embodiment 2) FIG. 3 shows a schematic structure of a temperature distribution measuring apparatus according to an embodiment of the present invention. The pyroelectric infrared sensor 1, the infrared condensing lens 5 that condenses infrared rays incident on the infrared sensor 1, and the photocoupler 10 that detects the timing when the sensor crosses the slit plate 2 are configured in the same unit, and the rotary shaft A motor 9 rotates left and right around 8 as a center. Here, the photocoupler 5 is composed of a photodiode section 14 that emits light and a phototransistor section 15 that detects the light. On the other hand, a slit plate 2 having an infrared transmitting portion 3 and an infrared shielding portion 4 is installed on the front surfaces of the infrared sensor 1, the infrared condensing lens 5, and the photocoupler 10. A polyethylene cover 11 is installed for the purpose of preventing the entry of dust and the like. The motor 9, the slit plate 2, and the polyethylene cover 11 are supported by the sensor support 6.

FIG. 4 is a spread view of the slit plate 2. The slit plate 2 shown in the figure is a view seen from the infrared sensor 1 side. Observation is made in 10 horizontal directions by one-way scanning, that is, chopping is performed 10 times. It is possible to measure the temperature in the horizontal N direction at some points. The visual field measured by one chopping is determined by the distance between the infrared transmitting portion 3 and the infrared shielding portion 4 and the visual characteristic of the infrared condenser lens 5. Thermistor 12
Is used to measure the temperature of the infrared shielding portion 4 of the slit plate 2 and obtain an accurate temperature of a heat source to be described later, and a thermocouple or a platinum temperature measuring element may be used as long as it is a temperature sensor. Further, the reflection plate 13 is provided at equal intervals with the infrared shielding portion 4,
The light emitted from the photodiode section 14 of the photocoupler 10 is reflected, and the reflected light is received by the phototransistor section 15 to detect chopping ON / OFF signals when the lens crosses the slit plate 2. ing.

Now, when the motor 9 is driven in a state where the infrared sensor 1 is in the form of an array and the major axis direction thereof is set vertically, the infrared ray condensing lens 5 is incident when the infrared condensing lens 5 crosses the slit plate 2. The distribution of the amount of radiant heat in the column in the direction in which the infrared condenser lens 5 faces can be measured in order to give a change in In FIG. 5, the infrared condenser lens 5 has a slit plate 2
6 is a time chart showing the relationship between the chopping signal of the photocoupler 10 and the signal of the infrared sensor 1 when the infrared sensor 1 is traversed. When the signal of the infrared sensor 1 was sampled in synchronization with the chopping signal, the amount of radiant heat could be measured accurately.

The temperature of the heat source to be measured can be easily obtained by considering the temperature of the thermistor 12 provided on the slit plate 2 and the sensor output. (Embodiment 3) FIG. 6 is a schematic configuration diagram showing a structure for moving a slit plate in a temperature distribution measuring apparatus according to an embodiment of the present invention. Pawls 14 and 16 are provided on the lower left and right sides of the slit plate 2. Also, the slit plate 2 has a groove 1
It can be rotated by 5. Now, the motor is rotated in the same direction as the rotation direction of the timepiece (in the drawing), the infrared sensor 1 is rotated from left to right, and the data of each field of view is acquired. After completing the acquisition of the data of the entire visual field of one way, a part of the sensor rotation scanning unit hits the right pawl 16,
The slit plate 2 is moved by the width of the infrared transmitting portion 3. At that time, the rotation of the motor 9 is stopped. Next, when the motor 9 is rotated in the reverse direction to acquire data, the visual field corresponding to the one-way infrared shielding portion 4 is measured. After the data of the entire field of view has been acquired, a part of the rotary scanning unit 7 of the sensor now hits the left claw 14, the slit plate 2 moves by the width of the infrared transmitting unit 3, and if it returns to the initial state, it is a motor. Stop the rotation of 9. The rotation angle of the rotary scanning unit 7 of this sensor could be easily realized by using an electric contact or a photocoupler.

FIG. 7 schematically shows the field of view of the sensor. It is assumed that the horizontal detection viewing angle is 180 degrees and that it is divided into 10. The first step, the second step, the third step, ... When the infrared sensor 1 is first rotated in the order of 1 to 10 steps, the field of view from which data is obtained is an odd step of 1, 3, 5, 7, 9. Next, the slit plate 2 is shifted by the width of the infrared transmitting portion 3 and the infrared sensor 1 is rotated in the order of 1 step from 10 so that the field of view for which data is obtained becomes an even step of 2, 4, 6, 8, 10. Finally, synthesizing these data gives a two-dimensional temperature distribution in a space with no blind spots. As described above, the slit plate 2 can be slightly moved by the length of the infrared ray transmitting portion 3 about the rotation shaft 8 on the groove formed on the sensor support 6, and the reciprocating rotary scanning can be performed. Then, after performing the one-way measurement, the slit plate 2 is moved by the length of the infrared ray transmitting portion 3, the one-way blind spot is measured, and the two-dimensional temperature of the space is calculated by synthesizing the field of view. Distribution can be measured. (Embodiment 4) FIG. 8 is a block diagram of a temperature distribution measuring system according to the present invention. The analog signal obtained from the infrared sensor 1 is A / D converted by the signal processing unit 31.
To be converted. Furthermore, the server provided on the infrared shielding unit 4
An accurate temperature of the object is calculated in consideration of the temperature information from the mister 12. Color display suitable for each temperature is displayed on the thermal image display unit 32. Moreover, the human body detection algorithm using the fuzzy inference rule was able to obtain the number of human bodies, the position, and the movement state in the room from the obtained temperature distribution. This information can be applied to the control of air conditioning and lighting systems.

[0018]

As is apparent from the above description,
According to the present invention, by rotating and scanning the pyroelectric sensor with respect to the slit plate composed of the infrared transmitting part and the infrared shielding part, the static heat source can be detected and the temperature distribution of the space can be determined without having a movable part such as a chopper. It becomes possible to measure. Moreover, since the temperature of the slit plate that functions as a chopper can be accurately measured, the temperature of the heat source to be measured can be accurately obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a temperature distribution measuring device according to an embodiment of the present invention.

FIG. 2 is a diagram showing an operation time chart of the temperature distribution measuring apparatus in the embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing an outline of a temperature distribution measuring device in one embodiment of the present invention.

FIG. 4 is a schematic view of a slit plate according to an embodiment of the present invention.

FIG. 5 is a time chart showing the relationship between the chopping signal and the infrared sensor signal confirmed in the present invention.

FIG. 6 is a schematic configuration diagram showing a slit moving structure of the temperature distribution measuring device in one embodiment of the present invention.

FIG. 7 is a schematic view of a visual field of a temperature distribution measuring device according to an embodiment of the present invention.

FIG. 8 is a block diagram of a temperature distribution measuring system according to an embodiment of the present invention.

[Explanation of symbols]

 1 Infrared sensor 2 Slit plate 3 Infrared transmitting part 4 Infrared shielding part 5 Infrared condensing lens 6 Sensor support 7 Rotating scanning part 8 Rotating shaft 9 Motor 10 Photocoupler 11 Polyethylene cover 12 Thermistor 13 Reflector 14 Photodiode part 15 Photo Transistor section 16 Nail 21 Person 31 Signal processing section 32 Thermal image display section

Claims (9)

[Claims] 1. A slit plate having at least one pair of an infrared transmitting part and an infrared shielding part, an infrared detecting means arranged behind the slit plate, and a rotating means for rotating and scanning the infrared detecting means. A temperature distribution measuring device characterized by being provided. 2. The temperature distribution measuring device according to claim 1, wherein the light receiving portion of the infrared detecting means is a pyroelectric element. 3. The temperature distribution measuring device according to claim 1, further comprising means for moving the slit plate around the infrared detecting means. 4. The temperature distribution measuring device according to claim 3, wherein the slit plate has an arc shape and is provided with a rotating means. 5. The temperature distribution measuring device according to claim 1, further comprising means for measuring the temperature of the infrared shielding portion of the slit plate. 6. The temperature distribution measuring device according to claim 1, further comprising an infrared condenser lens on the front surface of the infrared detecting means. 7. The temperature distribution measuring device according to claim 6, wherein the infrared condenser lens has a width equal to or less than the width of the infrared transmitting portion of the slit plate. 8. A slit plate having at least one pair of an infrared transmitting part and an infrared shielding part, an infrared detecting means arranged behind the slit plate, and a rotating means for rotating and scanning the infrared detecting means. A temperature distribution measuring system characterized by displaying a temperature distribution of a space as a thermal image using a temperature distribution measuring device provided. 9. The temperature distribution measuring system according to claim 8, wherein the number, position and movement state of human bodies are detected by analyzing a thermal image obtained from the temperature distribution system.