JPH0633036U - Temperature sensor - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an inexpensive and high-performance non-contact temperature sensor. [Configuration] In a temperature sensor that measures the temperature of an object by detecting infrared rays emitted from the object with an infrared sensor,
The light path from the opening of the temperature sensor to the infrared sensor is bent at a right angle. [Effect] By bending the optical path at a right angle, the outer shape of the temperature sensor becomes thin. Therefore, an effective temperature sensor can be obtained by using the temperature measurement using infrared rays in a narrow place like the temperature measurement of the charging part of GIS.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a temperature sensor that detects infrared energy and measures the temperature of an object.

[0002]

[Prior art]

 9 and 10 show principle diagrams of a conventional example. Infrared radiation emitted from the object to be measured 30 according to the temperature of the object to be measured is condensed by the optical system including the lens 31 or the reflecting mirrors 38 and 39, and the infrared energy is detected by the infrared sensor 32. Normally, due to the improvement of the SN ratio or the restriction of the infrared sensor 32 (radiation energy change detection type), the chopper 33 is used to intermittently input the infrared sensor 32. Next, the temperature of the infrared sensor is corrected by the temperature correction circuit 34, and the emissivity correction unit 35 performs emissivity correction according to the emissivity of the surface of the DUT 30. After that, the temperature output is obtained through the linearizer 36 for converting the radiant energy into the temperature output. Reference numeral 37 is a temperature sensor for infrared output correction, and 40 is a protective window. If necessary, the lens and reflector are coated and filters are used to limit the detection infrared region.

[0003]

[Problems to be solved by the device]

The conventional temperature sensor described above is usually formed in a camera type. Therefore, for example, as shown in FIG. 11, the temperature sensor 40 is used for measuring the temperature of the internal charging unit 41 of a gas insulated switchgear (hereinafter referred to as “GIS”) in which an electric device is enclosed in a metal container 42 together with SF ₆ gas. If it is intended to use, the length Lc of the temperature sensor 40 is large with respect to the insulation distance L between the ground-side metal container 42 and the high-voltage charging section 41, so that the substantial insulation distance 1 becomes short. Therefore, in order to install the temperature sensor 40 in the GIS, the size of the actual insulation distance l is set to a predetermined distance, and the size of the entire GIS device becomes unnecessarily large.

In addition to the above problems, the conventional temperature sensor must use an expensive optical system such as the lens 31, the mirrors 38 and 39, and the chopper 33 is also expensive. It has problems such as large external shape and large power consumption. An object of the present invention is to provide an inexpensive and high-performance non-contact temperature sensor.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention is a temperature sensor that measures the temperature of an object by detecting the infrared rays emitted from the object with an infrared sensor, and the optical path from the opening of the temperature sensor to the infrared sensor is perpendicular. A bending mirror is provided.

[0006]

[Action]

 By bending the optical path at a right angle, the outer shape of the temperature sensor becomes thin, the length Lc becomes small, and the substantial insulation distance l is less likely to be shortened. Therefore, an effective temperature sensor can be obtained by using the temperature measurement using infrared rays in a narrow place like the temperature measurement of the charging part of GIS.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. In each drawing, the same reference numerals are given to those performing the same operation, and duplicate description will be omitted.

Example 1 An example in which the temperature sensor of the present invention is applied to measure the temperature of a charging part of a GIS (gas insulated switchgear) will be described as Example 1 with reference to FIGS. 1 to 3. FIG. 1 is a side sectional view of a temperature sensor of this example, and FIG. 2 is a perspective view thereof. The temperature sensor 1 is configured by accommodating an infrared sensor 2, a concave mirror 3, and a pinhole 4 in an outer box 5, which has an opening 6 and is attached to a ground plane 8. Reference numeral 7 is a charging part of an object whose temperature is measured, and infrared rays corresponding to the temperature are emitted. The emitted infrared rays enter the outer box 5 through the opening 6 of the temperature sensor 1, and are converged by the off-axis concave mirror 3 to change the optical path to a right angle. The collected infrared rays pass through the pinhole 4 and reach the infrared sensor 2. If necessary, a cover made of an infrared transmitting material may be used for the opening 6 so that the mirror does not become dirty. Here, the pinhole 4 is provided to eliminate the influence of infrared rays coming from other directions than the charging section 7 or reflection inside the outer box 5. As the infrared sensor 2, a sensor such as a thermopile that does not require a chopper is used.

The temperature sensor 1 configured as described above is provided at a required position of the GIS, and the output from each temperature sensor 1 is input to the CPU 10 through the amplifier 9, as shown in FIG. Further, although the correction temperature sensor 11 for detecting the ambient temperature is provided to correct the temperature characteristic of the infrared sensor 2, the ambient temperature may be measured only at one representative point of the entire GIS. The output of the correction temperature sensor 11 is also input to the CPU 10 through the amplifier 9. When the distance between the temperature sensor 1 and the CPU 10 becomes long, the amplifier 9 may be housed in each temperature sensor 1.

In the temperature sensor 1 of the present embodiment described above, the distance from the light collecting portion 7 to the infrared sensor 2 is changed from the distance L 1 between the charging section 7 and the ground plane 8 by bending the infrared optical path at a right angle. Since the temperature sensor 1 can be excluded, the length of the temperature sensor 1 can be reduced, and the dimension inside the GIS does not have to be increased. Furthermore, in this example, since the off-axis concave mirror 3 is used, the space for the optical path after the temperature sensor 1 is bent at a right angle becomes small, and the thickness of the temperature sensor 1 can be further reduced. Therefore, the distance 1 between the charging unit 7 and the ground potential portion can be increased. Further, the concave mirror 3 can be manufactured by a press iron plate and chrome plating, etc., and since the number of parts is smaller than that of the conventional one, the cost is further reduced. Since the infrared sensor 2 can also be covered by the metal outer box 5, it is not affected by high voltage induction. As shown in FIG. 4, it is preferable that the outer case 5 has rounded corners so that the electric field around the temperature sensor 1 is relaxed.

[Embodiment 2] In the example described above, the concave mirror 3 bends the optical path at a right angle and collects light at the same time. However, bending the optical path at a right angle and condensing light are different members. This may be carried out by the above method, which will be described as a second embodiment with reference to FIG. In the figure, infrared rays radiated from the charging section 7 enter the outer box 5 through the opening 6 of the temperature sensor 1, are bent at a right angle by the plane mirror 26, and are converged on the infrared sensor 2 by the concave mirror 3. The second embodiment is the same as the first embodiment except that the plane mirror 26 and the concave mirror 3 are different, and the length of the temperature sensor is shortened by bending the infrared optical path at a right angle, and the inside of the GIS. It does not increase the size. However, in this example, since the plane mirror 26 only bends the optical path and does not collect light, the thickness of the temperature sensor 1 is thicker than that of the first embodiment, but its outer shape is significantly thinner than that of the conventional one. It can be done.

[Third Embodiment] In the first and second embodiments, since the temperature sensor 1 is fixedly installed, the measured portion is also fixed. On the other hand, an example in which the measured portion is variable will be described as a third embodiment with reference to FIGS. 6 and 7. In FIG. 6, reference numeral 12 is a mounting frame for mounting the opening 6 of the temperature sensor 1 in a variable direction. The mounting frame 12 includes an inner frame 13 and an outer frame 14. Shafts 15 and 16 are provided on both side surfaces of the outer box 5 of the temperature sensor 1, and the shafts are inserted into a hole 17 and a long hole 18 provided in the inner frame 13. Further, shafts 20 and 21 are provided on the other side surfaces of the inner frame 13 and are inserted into the holes 22 and the long holes 23 provided in the outer frame 14. The shafts 16 and 21 inserted into the long holes 18 and 23 are fixed to predetermined positions of the long holes by thumbscrews 19 and 24.

In order to change the direction of the temperature sensor 1, loosen the thumbscrews 19 and 24 and then move the temperature sensor 1 to center the shafts 15 and 20 inserted in the holes 17 and 22 and the other shaft 16, 21 move in the long holes 18, 23, and the temperature sensor 1 changes the direction of the opening 6 freely. When the thumbscrews 19 and 24 are tightened in the desired direction, the temperature sensor 1 is fixed in the desired direction as it is. As a result, the temperature sensor 1 of the present example can move as shown by the arrow in the measurement portion of the hatched portion as shown in FIG. Therefore, it is possible to cover a location where temperature can be measured in a wide range like the matrix surface ω shown.

[Fourth Embodiment] In the first to third embodiments described above, one temperature sensor is provided with one infrared sensor. However, one temperature sensor has a plurality of infrared rays. By providing the sensor, it is possible to measure the temperature at a plurality of points with one temperature sensor. This example will be described as Example 5 with reference to FIG. The figure shows the principle of this example. When the matrix surface ω on which the object to be measured is placed is condensed by the concave mirror 3, a virtual matrix surface ω ′ is formed. By moving the infrared sensor 2 on the virtual matrix surface ω ′, the measured position moves on the matrix surface ω. Therefore, if multiple points to be measured are set on the matrix surface ω and multiple infrared sensors 2 are provided at the points on the virtual matrix surface ω'corresponding to the points, several points can be obtained with one sensor unit. The temperature of can be monitored.

[0015]

[Effect of device]

 According to the present invention, in a temperature sensor that measures the temperature of an object by detecting infrared rays emitted from the object with an infrared sensor, a reflecting mirror that bends the optical path from the opening of the temperature sensor to the infrared sensor at a right angle is provided. As a result, a thin temperature sensor can be obtained. Therefore, when this temperature sensor is used to measure the temperature of, for example, the charging part of a GIS, it is less likely that the substantial insulation distance between the charging part and the installation surface will be shortened. Therefore, an effective temperature sensor can be obtained by using the temperature measurement using infrared rays in a narrow place like the temperature measurement of the charging part of GIS. Further, the temperature sensor of the present invention has only a mirror and an infrared sensor in the sensor, and since there is only one temperature sensor to be corrected, the number of parts is small and the temperature sensor can be manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a side sectional view of a first embodiment of a temperature sensor of the present invention.

FIG. 2 is a perspective view of Embodiment 1 of the temperature sensor of the present invention.

FIG. 3 is a circuit diagram of a temperature sensor of the present invention.

FIG. 4 is a side sectional view of a modification of the temperature sensor according to the first embodiment of the present invention.

FIG. 5 is a side sectional view of a second embodiment of the present invention.

FIG. 6 is a perspective view of a temperature sensor according to a third embodiment of the present invention.

7 is a perspective view showing a range in which the temperature sensor of FIG. 6 can measure.

FIG. 8 is a principle diagram of Embodiment 4 of the temperature sensor of the present invention.

FIG. 9 is a principle diagram of a first example of a conventional temperature sensor.

FIG. 10 is a principle diagram of a second example of a conventional temperature sensor.

FIG. 11 is a side view in which a conventional temperature sensor is applied to GIS.

[Explanation of symbols]

 1 ... Temperature sensor 2 ... Infrared sensor 3 ... Concave mirror 5 ... Outer box 6 ... Opening 7 ... Charging part 9 ... Amplifier 10 ... CPU 11 ... Temperature correction temperature sensor 12 ... Mounting frame 26 ... Plane mirror

Claims (5)

[Scope of utility model registration request] 1. A temperature sensor for measuring the temperature of an object by detecting infrared rays radiated from the object by an infrared sensor, wherein a reflecting mirror for bending an optical path from an opening of the temperature sensor to the infrared sensor at a right angle is provided. A temperature sensor characterized by. 2. The temperature sensor according to claim 1, wherein a concave mirror is used as the reflecting mirror. 3. The temperature sensor according to claim 1, wherein the reflecting mirror is a plane mirror, and a concave mirror for collecting infrared rays reflected from the plane mirror on an infrared sensor is provided. 4. The temperature sensor according to claim 1, further comprising a structure for changing a direction of an opening of the temperature sensor. 5. The temperature sensor according to claim 1, wherein a plurality of infrared sensors are provided in one temperature sensor so that the temperature at a plurality of points can be monitored by one temperature sensor.