JPH0729427U - Online inspection device for radiation thermometer - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an online inspection device for a radiation thermometer, which has the same performance as a blackbody furnace and does not require skill and can be inspected in a short time. [Structure] A diffused antireflection coating is applied to the inside of the radiation thermometer 11 to be inspected. A light bulb 1 that is arranged with its optical axis aligned with 11.
5 and a stabilized power supply 16 for the temperature calibrator that lights the bulb 15.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an on-line detection device for a radiation thermometer, which can grasp the accuracy of the radiation thermometer in a short time.

[0002]

[Prior art]

 Conventionally, a radiation thermometer is used to measure the surface temperature of a hot object. This radiation thermometer is an instrument that consists of an optical system consisting of a lens and a spherical mirror, and a detection system that is determined by the temperature measurement range. In particular, as shown in FIG. 4 in the steel industry, a two-color thermometer, which is often used for measuring the temperature of a steel plate, uses a photoelectric detector typified by PbS, Ge and InSb in its detection system. . In FIG. 4, when the infrared ray 30 corresponding to the surface temperature is incident on the light receiving section of the radiation thermometer 31, the infrared detecting element in the light receiving section carries out opto-electric conversion, and a converted signal 32 is output. This output characteristic is an exponential curve (measured value) as shown in A of FIG. A polygonal line compensator 33 is provided to correct this exponential curve, and a linear compensation value C is provided. The compensated output is recorded by a temperature recording output meter 34 or further output as a control signal 35. .

The installation location of the radiation thermometer 31 is determined by the relationship between the measurement area and the light receiving area of the detector. Normally, the radiation thermometer 31 is placed in the immediate vicinity of the object to be measured, and therefore drift due to changes in the temperature around the detector is caused. In addition, measurement errors will occur due to dirt on the optical system due to dust and oil mist. However, in order to ensure quality, the measurement accuracy is always required to be the accuracy limit value peculiar to the instrument. Therefore, the radiation thermometer 31 needs to be calibrated, but at present, it is done by comparison with the reference temperature of the blackbody furnace. FIG. 6 is a system diagram for calibrating the radiation thermometer 31 of FIG. 4 by the blackbody furnace 36. In order to raise and lower the temperature of the black body furnace 36 and maintain it at a constant temperature, the black body furnace control power supply 37 is controlled to measure the temperature-output relationship.

[0004]

However, regarding the calibration of the conventional radiation thermometer, the black body furnace control power supply is controlled in order to raise and lower the temperature of the black body furnace and maintain it at a constant temperature. However, it took a long time to raise and lower the temperature of the blackbody furnace, and at the same time, it had to be removed from the line where the radiation thermometer was installed. Furthermore, the operation of the blackbody furnace required skill in measuring, for example, which part of the blackbody furnace and how to control the temperature. For this reason, a skilled person is required for the operation, and a long calibration time (about 12 hours / unit) is required. Therefore, in the worst case, the manufacturing process may have to be stopped. Therefore, the drift due to the change in the temperature around the detector and the temperature error due to the dirt on the optical system cannot be grasped in real time, and real-time accuracy grasp under operating conditions was a big problem from the viewpoint of quality assurance. The present invention has been made in view of such circumstances, and has a performance equivalent to that of a black body furnace, does not require online skill, and can perform an inspection in a short time with a radiation thermometer. The purpose is to provide an online inspection device of.

[0005]

[Means for Solving the Problems]

 The radiation thermometer on-line inspection device according to claim 1, which is in line with the above object, has an anti-diffuse coating applied inside, and the opening of the radiation thermometer to be inspected is removable in a sealed state. It is configured to have a measuring tube, a light bulb arranged on the measuring tube with the radiation thermometer aligned with the optical axis, and a temperature calibrator power source for lighting the light bulb.

[0006]

[Action]

 In the radiation thermometer online inspection device according to the present invention, since the diffuse reflection preventing paint is applied to the inside of the measuring tube in which the bulb is installed, noise due to diffuse reflection of infrared light emitted from the bulb causes No error is generated. In addition, since the input value radiated from the light bulb and input to the radiation thermometer is the value that was calibrated by the power supply for the temperature calibrator that was adjusted and set in advance, only the radiation light is input to the radiation thermometer. You can check the accuracy of the radiation thermometer.

[0007]

【Example】

 Next, an embodiment of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 shows the entire structure of the online inspection device 10 for the radiation thermometer, which shows the relationship with the light receiving part 12 of the radiation thermometer 11, FIG. 2 shows the temperature inspection system diagram, and FIG. 3 shows the temperature after inspection. It is an adjustment point diagram of output characteristics. As shown in FIG. 1, the radiation thermometer online inspection device 10 according to the embodiment of the present invention is coated with diffused reflection preventing paint inside, and is sealed in the light receiving part 12 of the radiation thermometer 11 to be calibrated. The opening 13 has a detachable measuring cylinder 14, a light bulb 15 arranged on the measuring cylinder 14 so that the radiation thermometer 11 is aligned with the optical axis, and a temperature calibrator power supply 16 for lighting the light bulb 15. is doing. These will be described in detail below. The measuring tube 14 is provided with a seal material 17 on the inner surface on the side of the opening 13 so that the measuring tube 14 can be sealed with the light receiving part 12 of the radiation thermometer 11, and on the opposite side the radiation thermometer 11 and the optical axis. And the light bulb 15 is provided. The light bulb 15 has the same performance as a black body furnace and is connected to a temperature calibrator power source 16 outside the measuring cylinder 14. Further, the head of the light bulb 15 is configured such that infrared light is focused on the lens of the radiation thermometer 11 through a special lens 18, as shown in FIG. The power supply 16 for the temperature calibrator can be a small battery (DC12V) so that it can be used even when there is no AC power supply at AC100V and the inspection place. It weighs about 3Kg / unit and is light. It should be portable. Further, it is assumed that the output power supply variation rate of the temperature calibrator power supply 16 is + -0.1% of the maximum output, which can be kept within the accuracy as the light quantity variation and the temperature variation output of the light bulb 15. Here, it is also possible to use a stabilized power supply obtained by rectifying an AC power supply as the power supply.

A method of checking the radiation thermometer 11 will be described with reference to FIG. First, between the temperature calibrator power supply 16 and the light bulb 15, the surface temperature of the light bulb 15 is measured using a standard thermometer, and the relationship between the input voltage of the temperature calibrator power supply 16 and the temperature of the light bulb 15 is measured. Record. Next, when inspecting the radiation thermometer 11 in the line, as shown in FIG. 1, the light receiving portion 12 of the radiation thermometer 11 is hermetically sealed in the measuring tube 14, and both are fixed. As shown in, the voltage required for causing the light bulb 15 to generate a predetermined temperature is input to the temperature calibrator power supply 16 based on the data measured in advance. As a result, the infrared light emitted from the light bulb 15 having a predetermined temperature passes through the light receiving portion 12 of the radiation thermometer 11 that is hermetically coupled, is photo-electrically converted, and enters the temperature recording output meter 19 as a converted signal. I will be forced. As a result, the temperature-output characteristic of the radiation thermometer 11 that is inspected online is determined. Note that FIG. 3 shows a method of adjusting the temperature-output characteristic of the radiation thermometer 11 after inspection. As shown in the figure, perform 0 adjustment and span adjustment to the reference value adjusted by the blackbody furnace.

[0009]

[Effect of device]

 The radiation thermometer on-line inspection device according to claim 1, wherein a diffuse reflection preventing paint is applied to the inside thereof, and a measuring tube whose opening is detachably attached in a sealed state to a light receiving portion of the radiation thermometer to be inspected, Since the measuring tube has a light bulb arranged in alignment with the radiation thermometer and the optical axis and a power source for the temperature calibrator for lighting the light bulb, the radiation thermometer can be operated online in a short time and , It can be inspected accurately without requiring any skill.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an online inspection device for a radiation thermometer according to an embodiment of the present invention.

FIG. 2 is a temperature check system diagram.

FIG. 3 is a diagram showing an adjustment procedure of temperature-output characteristics after inspection.

FIG. 4 is a standard configuration diagram of temperature measurement using a conventional radiation thermometer.

FIG. 5 is a diagram showing a method of correcting measured values.

FIG. 6 is a temperature calibration system diagram using a blackbody furnace.

[Explanation of symbols]

 10 Online inspection device for radiation thermometer 11 Radiation thermometer 12 Light receiving part 13 Opening 14 Measuring tube 15 Light bulb 16 Power supply for temperature calibrator 17 Seal material 18 Lens 19 Temperature recording output meter 30 Infrared 31 Radiation thermometer 32 Conversion signal 33 Broken line compensator 34 Temperature recording output meter 35 Control signal 36 Blackbody furnace 37 Blackbody furnace control power supply

Claims (1)

[Scope of utility model registration request] 1. A measuring tube having an anti-diffuse reflection coating applied to the inside thereof, the opening of which is detachably attached in a sealed state to a light receiving part of a radiation thermometer to be inspected, and the radiation thermometer and the optical axis in the measuring tube. An on-line inspection device for a radiation thermometer, comprising: a light bulb arranged to match the light bulb and a power source for a temperature calibrator that lights the light bulb.