Scanning radiation thermometer

Abstract

To detect a self-temperature by a simple configuration.SOLUTION: A scan-type radiation thermometer 1 includes: a 4-plane rotary mirror 11 driven to rotate by a motor and having frame-like 4 reflection surfaces 11a for reflecting radiation light from a measurement target W; scan means 2 for scanning the radiation light from the measurement target W in a scan range A; and detection means 4 for detecting the radiation light from the measurement target W scanned by the scan means 2. The 4-plane rotary mirror 11 reflects the radiation light from the detection means 4 toward a detection surface of the detection means 4 when the reflection surface 11a faces the detection surface of the detection means 4.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention is a scanning method for measuring the temperature at each position on the object by scanning the light emitted from the object in a predetermined scanning range. dismissal This relates to a thermometer. [Background technology]

[0002] Running dismissal A radiation thermometer is conventionally known as a thermometer that measures the temperature at each position on a measurement object by scanning the radiation from the measurement object over a predetermined scanning range.

[0003] For example, the following Patent Document 1 dismissal In a thermometer, to measure the temperature at each position on the object, a polygon mirror with multiple reflective surfaces at different inclination angles on its side is rotated by a motor to scan the object surface in two dimensions, and the infrared light from the object surface is reflected by the polygon mirror. The measurement light reflected by this polygon mirror is then focused on the detection surface of an infrared detector by a focusing lens.

[0004] In addition, the running of the following Patent Document 1 dismissal In the infrared thermometer, a chopper with eight blades that is rotated by a motor is placed between the infrared detector and the polygon mirror, and one of the chopper blades has a mirror on the surface facing the infrared detector to detect infrared rays that are reflected from the infrared detector itself. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 04-002929 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the running speed of the above-mentioned Patent Document 1 dismissalIn a configuration that uses a chopper, such as a pyrometer, when reflecting and detecting infrared rays from the infrared detector itself, not only the polygon mirror but also the chopper must be rotated by a motor, which poses the problem of requiring a separate motor and increasing the number of components.

[0007] Therefore, the present invention has been made in consideration of the above problems, and provides a driving device capable of detecting its own temperature with a simple configuration. dismissal The present invention aims to provide a radiation thermometer. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention provides a driving dismissal The radiation thermometer scans the radiation from the object to be measured in a predetermined scanning range to measure the temperature at each position on the object. dismissal In the pyrometer, a scanning means that is rotationally driven by a motor and includes a four-sided rotating mirror having four frame-shaped reflecting surfaces that reflect the radiation from the measurement object, and that scans the radiation from the measurement object within the scanning range; a detecting means for detecting radiation from the measurement object scanned by the scanning means; The four-surface rotating mirror is positioned outside the rotation path of the four-surface rotating mirror, and faces the detection surface of the detecting means in parallel. On the inner wall of the part or housing that fixes the motor and an auxiliary reflecting means for reflecting, when the reflecting surface of the four-face rotating mirror faces the detecting surface of the detecting means, the radiated light emitted by the detecting means and not reflected by the reflecting surface of the four-face rotating mirror, toward the detecting surface of the detecting means, The four-facet rotating mirror is characterized in that when the reflecting surface faces the detection surface of the detection means, it reflects the radiation emitted by the detection means toward the detection surface of the detection means. [Effects of the Invention]

[0009] According to the present invention, when the detection means measures its own temperature by reflecting the radiated light emitted by the detection means, the four-sided rotating mirror can also be used to reflect the radiated light from the surface of the object to be measured. Compared to a conventional configuration in which a chopper with a mirror installed in part is rotated by a motor, the components can be simplified without adding an extra motor. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing the overall configuration of a scanning radiation thermometer according to the present invention; [Figure 2] FIG. 2 is a partial cross-sectional view of a scanning means of the scanning radiation thermometer according to the present invention. [Figure 3] 3A and 3B are diagrams showing an example of the configuration of the visualizing means of the scanning radiation thermometer according to the present invention and the emitted light; [Figure 4] 5A and 5B are diagrams showing other configuration examples of the visualizing means of the scanning radiation thermometer according to the present invention and the emitted light; [Figure 5] 5A and 5B are diagrams showing other configuration examples of the visualizing means of the scanning radiation thermometer according to the present invention and the emitted light; DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0012] As shown in FIG. dismissal The pyrometer 1 scans the radiation from the surface of the object W over a predetermined scanning range A (e.g., 90°) to measure the temperature at each position on the surface of the object W, and is generally composed of a scanning means 2, a focusing means 3, a detection means 4, a visual determination means 5, and an auxiliary reflection means 6.

[0013] The scanning means 2 has a frame-shaped four-faceted rotating mirror 11, in which adjacent reflecting surfaces 11a form a right angle, as a rotating body that is rotated by the motor 7 in Fig. 2. When the rotational force of the motor 7 is transmitted to the rotation axis 11b via a pair of magnetic couplings 15 (described later), the four-faceted rotating mirror 11 is rotated around the rotation axis 11b in the direction of arrow B in Fig. 1. The scanning means 2 scans a predetermined scanning range A by the rotation of the four-faceted rotating mirror 11, and reflects the radiation from the surface of the measurement object W toward the light collecting means 3.

[0014] Furthermore, the configuration of the scanning means 2 will be described with reference to the cross-sectional view of Fig. 2. The four-facet rotating mirror 11 of the scanning means 2 has a cylindrical portion 12 having a flange 12a on which four reflecting surfaces 11a are erected, and is connected to a rotation shaft 11b via a bearing 13.

[0015] The four-face rotating mirror 11 is connected to the motor 7 via a pair of magnetic couplings 15 in which an elastic body 14 is sandwiched in the gap portion.

[0016] The pair of magnetic couplings 15 consists of a rotating body side magnetic coupling 16 and a motor side magnetic coupling 17. The rotating body side magnetic coupling 16 is attached to the tip end (upper end in FIG. 2) of the rotating shaft 11b inside the cylindrical portion 12, and is composed of a magnet portion 16a and a holder portion 16b that holds the magnet portion 16a.

[0017] The motor-side magnetic coupling 17 is attached to the tip end (lower end in Figure 2) of the rotating shaft 7a of the motor 7, and is composed of a magnet part 17a having the same configuration as the rotating body-side magnetic coupling 16, and a holder part 17b that holds the magnet part 17a.

[0018] The elastic body 14 is made of, for example, rubber, sponge, or the like, and is formed in a shape (shape having a substantially similar outer shape) that matches the end face shapes of the magnet portion 16a of the rotor-side magnetic coupling 16 and the magnet portion 17a of the motor-side magnetic coupling 17, with their centers aligned so that they can fit inside the magnet portions 16a, 17a. Specifically, if the end face shapes of the magnet portion 16a of the rotor-side magnetic coupling 16 and the magnet portion 17a of the motor-side magnetic coupling 17 are circular, the elastic body 14 is formed in a ring shape so that they can fit inside the magnet portions 16a, 17a with their centers aligned, and if the end face shapes of the magnet portion 16a of the rotor-side magnetic coupling 16 and the magnet portion 17a of the motor-side magnetic coupling 17 are rectangular, the elastic body 14 is formed in a frame shape so that they can fit inside the magnet portions 16a, 17a with their centers aligned.

[0019] In other words, the elastic body 14 is not shaped to match the end face shape of the magnet parts 16a, 17a, and if it protrudes from the magnet parts 16a, 17a, the protruding parts will not be compressed and will become meaningless, and when compressed, it will deform into an irregular shape, dispersing the force and preventing even pressure from being applied, which is a concern as it may cause malfunctions during long-term use, so the elastic body 14 is shaped to match the end face shape of the magnet parts 16a, 17a and is contained within the magnet parts 16a, 17a with its centers aligned.

[0020] The elastic body 14 prevents the bearing inside the motor 7 from being damaged by a thrust load (a load acting in the direction of the rotation shaft 7a of the motor 7) due to magnetic force, and is pressed against the magnet portion 16a of the rotor-side magnetic coupling 16, and is provided in close contact and crushed state between the magnet portion 16a of the rotor-side magnetic coupling 16 and the magnet portion 17a of the motor-side magnetic coupling 17. As a result, when the rotational force of the motor 7 is transmitted to the four-sided rotating mirror 11 by the pair of magnetic couplings 15 and drives it to rotate, the magnetic attractive force between the magnet portion 16a of the rotor-side magnetic coupling 16 and the magnet portion 17a of the motor-side magnetic coupling 17 is canceled by the repulsive force of the elastic body 14, thereby reducing the load on the motor 7.

[0021] The elastic body 14 can be attached to the pair of magnetic couplings 15 by fixing only with the compressive force of the pair of magnetic couplings 15, by fixing with double-sided tape to the constant rotation side magnetic coupling 16 or the rotating body side magnetic coupling 17, or by fixing with adhesive to the constant rotation side magnetic coupling 16 or the rotating body side magnetic coupling 17. Using double-sided tape or adhesive increases the adhesion of the elastic body 14 to the pair of magnetic couplings 15 and also makes assembly easier.

[0022] The light collecting means 3 is composed of a collecting lens, and collects the light emitted from the measurement object W scanned by the scanning means 2 onto the detection means 4.

[0023] The detection means 4 has a detection element (single element or multiple elements) arranged thereon, and detects the light emitted from the measurement object W, which is collected by the light collecting means 3, on the detection surface of the detection element. The light emitted from the measurement object W, detected by the detection means 4, is converted into an electrical signal, and the temperature at each position on the surface of the measurement object W is calculated by conventionally well-known signal processing (including correction for temperature drift, which will be described later).

[0024] The visualizing means 5 is configured with a laser diode 5a and an optical system 5b that appropriately combines a collimating lens, a rod lens, and a triangular mirror so as to obtain a laser visual range angle C (e.g., 90°) that matches the scanning range A (e.g., 90°) of the scanning means 2 in Figure 1.

[0025] In order to visually confirm the scanning range A of the measurement object W, the visual determination means 5 converts the optical path of laser light (visible light: for example, red light) from the laser diode 5a using an optical system 5b, and emits the laser light whose optical path has been converted toward the measurement object W at a laser visual range angle C that matches the scanning range A. The visual determination means 5 can have any of the configurations shown in Fig. 3(a), Fig. 4(a), and Fig. 5(a).

[0026] 3(a) is configured with a laser diode 5a and an optical system 5b including a collimator lens 5b1 and a rod lens 5b2, and is arranged so that the centers of the emission surface of the laser diode 5a and the incidence surface of the collimator lens 5b1 coincide with the optical axis L. The rod lens 5b2 is arranged on the emission surface side of the collimator lens 5b1 and above the optical axis L. The rod lens 5b2 may also be arranged on the emission surface side of the collimator lens 5b1 and below the optical axis L.

[0027] In the visualizing means 5A shown in Fig. 3(a), the laser light (visible light: for example, red) emitted from the laser diode 5a is narrowed down to a parallel beam R1 by a collimating lens 5b1, and then a part of the parallel beam R1 is made incident on a rod lens 5b2, while the remaining parallel beam R1 is allowed to pass through. As a result, as shown in Fig. 3(b), the light beam incident on the rod lens 5b2 is emitted as a linear beam R2, and the remaining parallel beam R1 is condensed at the center.

[0028] The visualizing means 5B in Fig. 4(a) is configured with a laser diode 5a, a collimating lens 5b1 as an optical system 5b, and a triangular prism mirror 5b3, and is arranged so that the centers of the emission surface of the laser diode 5a and the incidence surface of the collimating lens 5b1 coincide with the optical axis L. The triangular prism mirror 5b3 is arranged above the optical axis L with its acute angle facing the collimating lens 5b1. The triangular prism mirror 5b3 may also be arranged below the optical axis L with its acute angle facing the collimating lens 5b1.

[0029] In the visualizing means 5B in Fig. 4(a), the laser light (visible light: for example, red) emitted from the laser diode 5a is narrowed down to a parallel beam R1 by a collimating lens 5b1, and then a part of the parallel beam R1 is incident on two side surfaces of a triangular prism mirror 5b3, while the remaining parallel beam R1 is allowed to pass through. As a result, as shown in Fig. 4(b), the light rays incident on the two side surfaces of the triangular prism mirror 5b3 are reflected outward at a predetermined angle (for example, 22.5° when the angle of the acute angle of the triangular prism mirror 5b3 facing the emission surface of the laser diode 5a is 45° and the scanning range A is 90°), and are emitted as light R3 and R4, and the remaining parallel beam R1 is condensed at the center.

[0030] The visualizing means 5C in FIG. 5(a) is configured with a laser diode 5a and an optical system 5b including a collimating lens 5b1, a rod lens 5b2, and a triangular prism mirror 5b3, and is arranged so that the centers of the emission surface of the laser diode 5a and the incidence surface of the collimating lens 5b1 coincide with the optical axis L. The triangular prism mirror 5b3 is arranged above the optical axis L with its acute angle facing the collimating lens 5b1, and the rod lens 5b2 is arranged above the triangular prism mirror 5b3 on the emission surface side of the collimating lens 5b1. Alternatively, the triangular prism mirror 5b3 may be arranged below the optical axis L with its acute angle facing the collimating lens 5b1, and the rod lens 5b2 may be arranged below the triangular prism mirror 5b3.

[0031] In the visualizing means 5C in Fig. 5(a), the laser light (visible light: for example, red) emitted from the laser diode 5a is narrowed down to a parallel beam R1 by a collimating lens 5b1, and then a part of the parallel beam R1 is incident on a rod lens 5b2, another part of the parallel beam R1 is incident on two side surfaces of a triangular prism mirror 5b3, and the remaining parallel beam R1 is allowed to pass through as is. As a result, as shown in Fig. 5(b), the light beam incident on the rod lens 5b2 is emitted as a linear beam R2, and the light beam incident on the two side surfaces of the triangular prism mirror 5b3 is emitted as beams R3 and R4 reflected outward at a predetermined angle (for example, 22.5° when the angle of the acute angle of the triangular prism mirror 5b3 facing the emission surface of the laser diode 5a is 45° and the scanning range A is 90°), and the remaining parallel beam R1 is condensed at the center.

[0032] The auxiliary reflecting means 6 is placed parallel to and facing the detection surface of the detection means 4 at a position off the rotation trajectory of the four-facet rotating mirror 11 in order to measure the temperature drift when the radiant light from the measurement object W is not incident on the detection surface of the detection means 4. Specifically, the auxiliary reflecting means 6 is attached to a mirror cover 18 (the part that secures the motor 7 in FIG. 2 ) that prevents stray light from entering the four-facet rotating mirror 11 or to the inner wall surface of the housing in order to miniaturize the device in consideration of ease of assembly and an increase in the number of parts. When reflecting the radiation light emitted by the detecting means 4 (including the radiation light emitted by the focusing means 3) and measuring the reflected light incident on the detecting surface of the detecting means 4 as temperature drift, the auxiliary reflecting means 6 reflects the radiation light emitted by the detecting means 4 that cannot be reflected by the reflecting surface 11a of the four-facet rotating mirror 11, i.e., the radiation light that cannot be covered by the reflecting surface 11a of the four-facet rotating mirror 11 due to insufficient field of view, towards the detecting surface of the detecting means 4 at a position where the left reflecting surface 11a of the four-facet rotating mirror 11 shown by the solid line in Figure 1 faces parallel to the detecting surface of the detecting means 4.

[0033] The auxiliary reflecting means 6 is provided when the effective aperture of the lens of the focusing means 3 is large and it is not possible to reflect the emitted light from the detecting means 4 and make it incident on the detecting surface of the detecting means 4 using only the four-face rotating mirror 11 of the scanning means 2.

[0034] In addition, if the effective aperture of the lens of the focusing means 3 is small and the radiation light from the detecting means 4 can be reflected by only the four-face rotating mirror 11 of the scanning means 2 to be incident on the detecting surface of the detecting means 4, the auxiliary reflecting means 6 can be omitted.

[0035] In this way, in the above-described embodiment, when the detecting means 4 measures its own temperature by reflecting the radiation emitted by the detecting means 4 (including the radiation emitted by the collecting means 3), the four-faceted rotating mirror 11 also serves to reflect the radiation from the surface of the object to be measured W to the collecting means 3. This makes it possible to simplify the components without adding an extra motor, compared to a configuration in which a chopper with a mirror provided on one part is rotated by a motor, as in Patent Document 1.

[0036] Furthermore, even if the effective aperture of the lens of the focusing means 3 is large and it is not possible to measure the self-temperature as described above using only the four-face rotating mirror 11, this can be achieved by simply arranging a mirror using the auxiliary reflecting means 6.

[0037] Furthermore, in the above-described embodiment, a configuration is adopted in which an elastic body 14 having a repulsive force is provided in the gap portion of a pair of magnetic couplings 15 that connect the motor 7 and the rotating body (four-face rotating mirror 11). As a result, the thrust load caused by the attraction of magnetic forces is reduced by the repulsive force of the elastic body 14, reducing the load on the motor 7 and preventing damage to the bearings inside the motor 7.

[0038] Furthermore, in the above-described embodiment, a pair of magnetic couplings 15 is used to connect the motor 7 and the rotating body (four-face rotating mirror 11). This solves the conventional problem of dust contamination due to wear of the timing belt, eliminates the need to realign the optical axis when replacing the motor, allows for rough positional repeatability, and allows for simple and easy motor replacement on-site, making it possible to take advantage of the advantages of magnetic coupling.

[0039] Furthermore, the above-described embodiment employs visualizing means 5A, 5B, and 5C having any of the configurations shown in FIGS. 3 to 5. According to visualizing means 5A of FIG. 3, a portion of the parallel light beam R1 is incident on rod lens 5b2, and the remaining parallel light beam R1 passes through as is, thereby enabling confirmation of the center position of scanning range (visual range) A. According to visualizing means 5B of FIG. 4, a portion of the parallel light beam R1 is incident on two side surfaces of triangular prism mirror 5b3, and the remaining parallel light beam R1 passes through as is, thereby enabling confirmation of not only the center position but also both end positions of scanning range (visual range) A. Furthermore, according to visualizing means 5C of FIG. 5, a configuration combining visualizing means 5A of FIG. 3 and visualizing means 5B of FIG. 4 allows confirmation of the center position and both end positions of scanning range (visual range) A.

[0040] In the above-described embodiment, the position where the elastic body 14 is provided is not limited to the gap portion of the pair of magnetic couplings 15 connecting the motor 7 and the four-face rotation mirror 11 in FIG. 2, but may be the gap portion of the pair of magnetic couplings when connecting the motor 7 and a rotating body to be rotated by the motor 7.

[0041] As described above, the driving dismissal Although the best mode of the pyrometer has been described, the present invention is not limited to the description and drawings of this mode. In other words, all other modes, embodiments, and operating techniques that can be made by those skilled in the art based on this mode are naturally included in the scope of the present invention. [Explanation of symbols]

[0042] 1 run dismissal radiation thermometer 2. Scanning means 3 Light collection means 4. Detection Methods 5A,5B,5C Visual means 5a laser diode 5b Optical system 5b1 Collimating Lens 5b2 Rod Lens 5b3 Triangular mirror 6 Auxiliary reflective means 6a Reflective surface 7 Motor 7a Rotation axis 11. 4-sided rotating mirror 11a Reflective surface 11b Rotation axis 12 Cylindrical part 12a flange 13 Bearings 14 Elastic Body 15 pairs of magnetic couplings 16 Rotor side magnetic coupling 16a Magnet part 16b Holder part 17 Motor side magnetic coupling 17a Magnet part 17b Holder part 18 Mirror Cover W Measurement target A Scanning Range B Rotation direction (four-sided rotating mirror) C Laser visibility angle L optical axis R1 parallel beam R2 Line of light R3,R4 Reflected light

Claims

[Claim 1] A scanning radiation thermometer measures the temperature at each position on a measurement object by scanning the radiation from the measurement object over a predetermined scanning range, a scanning means for scanning the radiation from the measurement object within the scanning range, the scanning means being rotated by a motor and including a four-surface rotating mirror having four frame-shaped reflecting surfaces that reflect the radiation from the measurement object; a detecting means for detecting radiation from the measurement object scanned by the scanning means; an auxiliary reflecting means that is arranged on an inner wall surface of a component or a housing that fixes the motor and faces parallel to the detection surface of the detection means at a position off the rotation locus of the four-faced rotating mirror, and that reflects, when the reflecting surface of the four-faced rotating mirror faces the detection surface of the detection means, radiation light that is emitted by the detection means and cannot be reflected by the reflecting surface of the four-faced rotating mirror toward the detection surface of the detection means; a scanning radiation thermometer, characterized in that the four-facet rotating mirror reflects the radiation emitted by the detecting means toward the detecting surface of the detecting means when the reflecting surface faces the detecting surface of the detecting means;

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