JPH09304184A - Temperature detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a temperature detector by which a temperature at a long distance and in a wide range can be detected precisely in a gigantic space such as a refuse pit or the like. SOLUTION: A temperature detector is provided with at least three temperature detectors which are provided with a plurality of pyroelectric thin-film heat detection element groups, with a chopper which opens and closes the passage of infrared rays incident on the pyroelectric thin-film heat detection element groups and with an infrared transmitting window material part 2 which is situated in the front part of the chopper. It is provided with a moving part 4 in which at least the three temperature detectors 1 are arranged on the same plane and with a scanning drive part 8 which turns the moving part 4. Temperature detectors 1b, 1v, 1d, 1e whose visual field range is small are situated on the center side of the moving part 4, temperature detectors 1a, 1f whose visual field range is larger than that of the temperature detectors situated on the center side of the moving part 4 are situated io both end sides of the moving part 4, and they are tilted at angles which take charge of respectively different visual field ranges.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature detecting device in a huge space such as a dust pit provided in association with an incinerator for incinerating municipal waste or the like.

[0002]

2. Description of the Related Art Conventionally, as a temperature detecting device for the entire surface of dust stored in a dust pit, there are a quantum infrared sensor and a thermal infrared sensor.
The quantum infrared sensor has high sensitivity and high response speed, but it requires cooling, which is expensive and difficult to maintain.

On the other hand, a thermal infrared sensor has a relatively low sensitivity and a slow response speed, but it is often put into practical use because it does not require expensive cooling. Among them, the pyroelectric infrared sensor utilizing the pyroelectric effect is often used.

In the case of using a pyroelectric infrared sensor, 2
As a means for obtaining a two-dimensional thermal image, there is a method of rotating a single array sensor having a one-dimensionally arranged pyroelectric heat detecting element. The outline is shown in FIG. In this, a temperature detector having a condenser mirror 25 for condensing infrared rays in front of the pyroelectric heat detection element 24 is rotated by a scan drive 8 to detect a temperature in a disk-shaped range. .

Further, there is one in which a reflection mirror is combined with a quantum infrared sensor and a two-dimensional thermal image is obtained by rotating the reflection mirror.

[0006]

However, the number of pyroelectric heat detecting elements that can be arranged within one centimeter is limited, and it is difficult to cover the field of view over a wide range. If you try to cover a wide field of view using a wide-angle lens,
At a long distance, the area occupied by each pyroelectric heat detection element becomes large, and the temperature of a high-temperature object in a small range is averaged with the ambient temperature, and accurate temperature measurement cannot be performed. Further, even if a rotation mechanism is added, there is a limit to the accurate temperature measurement of a wide range over a long distance with a single array sensor for the same reason.

A system using a quantum infrared sensor is
It is very expensive and requires tedious maintenance.

According to the present invention, temperature measurement over a long distance and a wide range in a huge space such as a dust pit can be detected with high accuracy by a relatively simple system configuration, and durability reliability of components is improved. The system provides easy maintenance.

[0009]

In order to solve the above-mentioned problems, the present invention provides a plurality of pyroelectric thin film heat detecting element groups, and an infrared transmitting lens integrated with the pyroelectric thin film heat detecting element groups. A chopper that opens and closes a path of infrared rays incident on the pyroelectric thin film heat detection element group through the infrared transmission lens, and a chopper drive motor that drives the chopper,
An infrared transparent window material portion located on the front surface of the chopper,
A reference temperature detecting means for detecting the temperature of the chopper, a control processing section for controlling the chopper, and for processing an output signal from the pyroelectric thin film heat detecting element group and a detection signal from the reference temperature detecting means. At least three or more temperature detectors each including a temperature calculation unit that calculates the temperature signal from the signal from the infrared detection processing unit are provided.

The temperature detector having a small field of view has a movable portion in which the three or more temperature detectors are arranged on the same plane, and a scan drive portion for rotating the movable portion. Of the temperature detector having a larger visual field range than the temperature detector located on the center side of the movable part,
It is located at both ends of the movable part and is tilted at an angle which covers different visual field ranges, and measures temperature over a long distance and a wide range.

Further, the present invention is characterized in that the air is blown to the infrared transmitting window material portion of the temperature detector to blow air to the outer wall portion of the temperature detector.

Further, the present invention has a blower circuit for blowing air to the scanning drive unit for rotating the movable portion of the temperature detector.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 is a plurality of pyroelectric thin film heat detecting element groups, an infrared transmitting lens integrated with the pyroelectric thin film heat detecting element group, and the infrared transmitting lens. A chopper that opens and closes a path of infrared rays incident on the pyroelectric thin film heat detection element group through the chopper, a chopper drive motor that drives the chopper, an infrared transmission window member portion located on the front surface of the chopper, and A reference temperature detecting means for detecting the temperature of the chopper, a control processing part for controlling the chopper, and for processing an output signal from the pyroelectric thin film heat detecting element group and a detection signal from the reference temperature detecting means, At least three or more temperature detectors configured by a temperature calculation unit that calculates and processes the signal of the infrared detection processing unit into temperature data are provided, and the three or more temperature detectors are arranged on the same plane. The temperature detector having a movable part and a scanning drive part for rotating the movable part, and having a small visual field range, is located on the center side of the movable part, and has a field of view from the temperature detector located on the center side of the movable part. The temperature detector having a large range is characterized in that it is located at both ends of the movable part and is inclined at an angle which covers different visual field ranges.

According to this structure, in a large rectangular space such as a dust pit whose height direction is longer than its width direction, the bottom of the dust pit located at the farthest distance can be measured by a temperature detector having a small visual field range. In addition, the measurement of both side wall surfaces of the garbage pit, which does not require long-distance measurement,
The temperature detector having a large field of view is responsible for the measurement, and the minimum number of temperature detectors can accurately measure the temperature in a long distance and a wide range.

According to a second aspect of the present invention, there is provided an air blowing circuit for blowing air to the infrared transmitting window material portion of the temperature detector and the outer wall portion of the temperature detector.

According to this structure, it is possible to prevent dust in the dust pit from adhering to the infrared transmitting window member.

Further, an air blowing circuit for blowing air to the outer wall portion of each temperature detector shuts off the ambient temperature in which the temperature detecting device is attached, so that the ambient temperature outside the device affects the temperature detector. Can be reduced.

At the same time, it is possible to prevent the temperature rise due to heat generation during the operation of the control processing section of the temperature detector, the temperature calculation section and the chopper driving motor.

According to a third aspect of the present invention, there is provided a blower circuit for blowing air to the scanning drive unit that rotates the movable portion of the temperature detector. As a result, it is possible to prevent the temperature from rising during the operation of the scan driver.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A temperature detecting device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention. In FIG. 1, 1a to 1f are temperature detectors, 2 is an infrared transmitting window member, 3 is a rotary shaft, 4 is a rotating body case covering the temperature detectors, and 5a to 5f are air in the infrared window of the temperature detectors. A blow-off port for blowing, 6 is a blower circuit section provided between the temperature detector and the rotating body case 4, and 7 is an air supply means for supplying air to the blower circuit section. Rotation of the scanning drive unit 8 causes the rotating body case 4 containing the individual temperature detectors to rotate around the rotation shaft 3, and the temperature of each of the temperature detectors is measured. The two-dimensional thermal image is sequentially transmitted to the thermal image processing unit 10. Further, the temperature detectors 1a to 1f are arranged in an array having a small visual field range.
Is located in the center of the rotating body case 4, and
The temperature detectors 1a and 1f, which have a larger visual field range than the temperature detectors located in the central part, are located on both ends of the rotating body case 4 and are inclined at angles to cover different visual field ranges.

Further, an air blowing circuit 11 is provided between the fixed case 12 and the scan driving unit 8 so that air can be blown to the scan driving unit 8.

FIG. 2 shows the state of attachment and the viewing angle in the dust pit of the detection device according to this embodiment. The temperature detecting device 13 is provided in the ceiling part 1 of the dust pit.
It is installed in the center of 4. The temperature detectors 1a to 1f have the respective viewing angles θa, θb, θc, θ.
It takes charge of d, θe, and θf and forms the entire visual field θ of the temperature detection device 13. Reference numeral 15 indicates dust, and 16 indicates a wall portion of the dust pit.

Here, for example, the height is 50 m and the width is 30 m.
When trying to measure the temperature of the m dust pit within the range of 80 ° in the total field of view, the diagonal line position with the longest measurement distance is 5
It is 2 m long, and the measurement of the diagonal position and the bottom of the pit must be a temperature detector with a small field of view of about 10 °, and the area covered by each pyroelectric heating element will be large, and the temperature of a high temperature object in a small range will be measured. Cannot be measured accurately because it is averaged with the ambient temperature. However, the measurement of the wall part 16 of the dust pit is
The distance is at most about 30 to 40 m, and accurate temperature measurement is possible even with a rather large temperature detector having a visual field range of approximately 20 °. Viewing angle 10 °
If only one of the temperature detectors is used, a total of eight temperature detectors are required, but the temperature detectors 1a, 1 located at both ends are required.
If two of f are handled by a temperature detector with a viewing angle of 20 °,
A total of 6 temperature detectors can be used.

That is, a temperature detector having a small field of view is arranged on the center side of the rotating body, and a temperature detector having a larger field of view than the temperature detectors located at the center of the rotating body is provided on both ends of the rotating body. By arranging, temperature detection of a long distance and a wide range can be performed with high precision by the minimum number of temperature detectors.

FIG. 3 is a diagram showing the internal construction of each of the temperature detectors 1a to 1f. The chopper driving motor 21 is driven by the control processing unit 18 to open / close the chopper 22. By this opening / closing operation, the amount of infrared rays passing through the infrared transmissive lens 20 and reaching the pyroelectric thin film heat detection element group 19 is reduced. Change. The output signal of the pyroelectric thin film heat detection element group 19 corresponding to this amount of change is processed by the control processing unit 18 together with the signal of the reference temperature detection means 23, and the temperature calculation unit 17 converts the temperature. There is.

The temperature of the measuring object is the output voltage of the pyroelectric thin film heat detecting element group 19 caused by the chopper temperature and the pyroelectric thin film heat detecting element caused by the temperature difference between the temperature measuring object and the temperature of the chopper. It is measured by the output voltage difference of the group and the chopper temperature detected by the reference temperature detecting means. Therefore, to measure the temperature of the object with high accuracy,
The reference temperature detecting means is required to accurately measure the chopper temperature and be in a stable temperature environment that is not influenced by the ambient temperature change. However, since the chopper 22 is a movable body, it is difficult to directly detect its temperature. In the dust pit, the temperature and humidity are high and the temperature inside the temperature detector is higher than the chopper temperature because the heat of the chopper driving motor 21 and the heat of the control processing unit 18 and the temperature calculation unit 17 are detected. Means 2
3 is not detected, or the reference temperature changes due to a change in the environmental temperature of this device, which is not a stable temperature environment. However, according to this embodiment, the blower circuit section 6 provided between the rotating body case 4 and each of the temperature detectors is blown with the outside air outside the dust pit or the conditioned air is blown. Each temperature detector 1a, 1b, 1c, 1
It is possible to cool d, 1e, and 1f, and at the same time, it is possible to shut off the ambient temperature in which the temperature detecting device is attached. As a result, each temperature detector is placed in a stable temperature environment.

Further, dust and dust are constantly floating in the dust pit due to taking in and out of dust and stirring, and there is a risk that dust and dust will adhere to the infrared transmitting window of the temperature detector. The air circuit that blows air to the window of the detector can prevent dust from adhering to the dust pit.

By having the air blowing circuit 11 for blowing air to the scan driving unit 8 shown in FIG. 1, it is possible to prevent the temperature of, for example, a stepping motor used as the scan driving unit 8 from rising, and to improve the durability and reliability of the stepping motor. It is possible to improve the property.

[0030]

As is apparent from the above-described embodiment, the invention according to claim 1 includes a plurality of pyroelectric thin film heat detection element groups,
An infrared transmission lens integrated with the pyroelectric thin film heat detection element group, a chopper for opening and closing a path of infrared rays incident on the pyroelectric thin film heat detection element group through the infrared transmission lens, and a driving chopper for this. Drive motor for chopper,
An infrared transmitting window member located on the front surface of the chopper, a reference temperature detecting means for detecting the temperature of the chopper, an output signal from the pyroelectric thin film heat detecting element group for controlling the chopper, and detecting the reference temperature. At least three temperature detectors each including a control processing unit that processes a detection signal from the means and a temperature calculation unit that processes the signal of the infrared detection processing unit into temperature data are provided. The temperature detector having a small field-of-view range is located on the center side of the movable section, and has a movable section in which the temperature detector is arranged on the same plane and a scanning drive section for rotating the movable section. The temperature detectors having a larger visual field range than the temperature detectors located on the center side of the part are characterized in that they are located at both ends of the movable part and are inclined at angles to cover different visual field ranges. It is possible to perform long distance and a wide range of temperatures detected with high accuracy with a minimum number of temperature detectors According to this configuration. In addition, the system configuration is relatively simple, so it is inexpensive.

According to a second aspect of the present invention, there is provided an infrared transmitting window member portion of the temperature detector and an air blowing circuit for blowing air to the outer wall portion of the temperature detector. The temperature detector is less likely to be affected by the ambient temperature and the temperature inside the temperature detector can be prevented from rising. This enables stable reference temperature detection and accurate temperature detection. Furthermore, the durability reliability of each electronic component that is responsible for the chopper drive motor, the control processing unit, and the temperature calculation unit can be improved.

The invention according to claim 3 has a blower circuit for blowing air to the scan drive section for rotating the movable section of the temperature detector. According to this configuration, the scan drive section is cooled. For example, it is possible to prevent the temperature rise of the stepping motor which is in charge of the scan driving unit and improve the durability reliability of the stepping motor.

As described above, the present invention has an effect that it is possible to accurately detect a temperature in a long distance and a wide range in the dust pit with a relatively simple system configuration.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a temperature detection device showing an embodiment of the present invention.

FIG. 2 is a view showing a mounting state and a viewing angle in a dust pit of a temperature detector according to an embodiment of the present invention.

FIG. 3 is a configuration diagram of a temperature detector in one embodiment of the present invention.

FIG. 4 is a schematic diagram of a temperature detector and a temperature detection range diagram in a conventional example.

[Explanation of symbols]

 1a Temperature Detector 1b Temperature Detector 1c Temperature Detector 1d Temperature Detector 1e Temperature Detector 1f Temperature Detector 2 Infrared Transmission Window Material 3 Rotating Axis 4 Rotating Body Case 5a Air Blowout 5b Air Blowout 5c Air Blowout 5e Air blowout port 5f Air blowout port 6 Blower circuit unit 7 Air supply unit 8 Scan drive unit 9 Transmission unit 10 Thermal image processing unit 11 Blower circuit unit 12 Fixed side case 13 Temperature detector 14 Dust pit ceiling 15 Dust 16 Dust pit wall 17 Temperature Calculation Section 18 Control Processing Section 19 Pyroelectric Thin Film Heat Detection Element Group 20 Infrared Transmission Lens 21 Chopper Drive Motor 22 Chopper 23 Reference Temperature Detection Means 24 Pyroelectric Thermal Detection Element 25 Condenser Mirror 26 Air Blowout 27 Overall Temperature detection range 28 Temperature detection range

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location G08B 17/12 G08B 17/12 A

Claims (3)

[Claims] 1. A pyroelectric thin film heat detecting element group, a plurality of pyroelectric thin film heat detecting element groups, an infrared transmitting lens integrated with the pyroelectric thin film heat detecting element group, and the pyroelectric thin film heat detecting element via the infrared transmitting lens. A chopper that opens and closes a path of infrared rays incident on the group, and a chopper drive motor that drives the chopper,
An infrared transparent window material portion located on the front surface of the chopper,
A reference temperature detecting means for detecting the temperature of the chopper, a control processing section for controlling the chopper, and for processing an output signal from the pyroelectric thin film heat detecting element group and a detection signal from the reference temperature detecting means. And at least three temperature detectors each including a temperature calculation unit that calculates a signal of the infrared detection processing unit into temperature data.
A movable part in which at least two temperature detectors are arranged on the same plane, and a scan drive part for rotating the movable part, and the temperature detector having a small visual field range is located on the center side of the movable part, The temperature detectors having a larger visual field range than the temperature detectors located on the center side of the movable part are positioned at both ends of the movable part, and are inclined at angles to cover different visual field ranges. apparatus. 2. The temperature detecting device according to claim 1, further comprising an infrared ray transmitting window member portion of the temperature detector and an air blowing circuit for blowing air to the outer wall portion of the temperature detector. 3. A blower circuit for blowing air to a scan drive unit for rotating a movable portion of the temperature detector.
The temperature detection device described.