WO2000022390A1

WO2000022390A1 - Infrared sensor and radiation thermometer

Info

Publication number: WO2000022390A1
Application number: PCT/JP1998/004653
Authority: WO
Inventors: Kazuhito Sakano
Original assignee: Kazuhito Sakano
Priority date: 1998-10-15
Filing date: 1998-10-15
Publication date: 2000-04-20
Also published as: JP3346583B2; AU3629899A; AU9461698A; WO2000022391A1

Abstract

A radiation thermometer having an infrared sensor, wherein the sensor, even when used in small electronic devices, can alleviate limitations on its position of installation. Specifically, a radiation thermometer comprising a body case (51), an infrared detection section (52) installed in the body case, and a temperature measuring circuit section (53), wherein the infrared detection section (52) has a sensor heating block (54) and a thermopile sensor (55), the temperature measuring circuit section (53) has printed circuit boards (56a, 56b), a switch (57), a liquid crystal display circuit (58), and a slide mechanism (59) and the slide mechanism (59) slides the thermopile (55) relative to the sensor heating block (54). The probe (60) at the tip is formed so that it becomes gradually narrower toward the front end. The infrared detection section (52) has the truncated cone-shaped thermopile sensor (55) and a hollow portion to accommodate the thermopile sensor (55).

Description

Specification

Infrared sensor and radiation thermometer

TECHNICAL FIELD The present invention relates to an infrared sensor and a radiation thermometer having the infrared sensor. More specifically, the present invention relates to an infrared sensor that detects infrared rays emitted from a measurement target and a radiation thermometer that detects infrared rays with the infrared sensor and measures the temperature of the measurement target in a non-contact manner.

BACKGROUND ART Conventionally, a non-contact measurement of a temperature of a measurement target has been performed by detecting infrared radiation radiated from the measurement target by using a radiation thermometer. For example, in recent years, thermometers emit more radiation from the eardrum and surrounding tissues than contact-type thermometers such as a sublingual thermometer that measures the temperature in the oral cavity and an axillary thermometer that measures the temperature of the axilla for reasons of hygiene and convenience. The demand for non-contact ear thermometers, which measure body temperature by detecting infrared radiation, is increasing.

Because the eardrum is located deep within the human body and is less susceptible to the external environment, one of the reasons why ear-type thermometers have attracted attention is that they can measure body temperature more accurately than other parts of the human body such as the oral cavity and axilla. It is.

Ear thermometers generally use a pyroelectric sensor or a thermopile sensor as an infrared sensor for detecting infrared radiation emitted from a measurement object. Pyroelectric sensors use a temperature change when they absorb infrared energy radiated from the object to be measured. The sensor detects a change in the surface charge of the pyroelectric body as an output. Since the pyroelectric sensor outputs an output only when the temperature of the pyroelectric element changes, the incident infrared ray is shoved to intermittently cut off and output continuously. On the other hand, a thermopile sensor is a sensor in which thermocouples are deposited using integrated circuit technology, and a continuous output for the temperature difference between the hot junction and the cold junction is obtained by a large number of directly connected thermocouples.

Hereinafter, a conventional infrared sensor and a radiation thermometer will be described as examples of a thermopile sensor and an ear thermometer using the thermopile sensor.

Conventional thermopile sensors include, for example, thermopile sensors shown in FIGS. 8 and 9. As shown in FIG. 8, such a thermopile sensor is electrically connected to a thermopile element 1 for receiving infrared rays, a heat sink 2 formed on the surface of the thermopile element 1 by vapor deposition or the like, and a thermocouple of the thermopile element 1. And a package 7 having an infrared receiving window 6.

The package 7 has a hollow cylindrical shape as shown in FIG. 9, and has a stem 5 attached to one end and an infrared receiving window 6 attached to the other end. The thermopile element 1 has a circular shape. Although not shown, a hot junction for receiving infrared rays is provided at the center of the thermopile element 1, and a cold junction is provided around the center.

The above-mentioned thermopile sensor converts infrared radiation energy into heat energy when infrared light from the measurement object that enters from the infrared light receiving window 6 provided in the package 7 enters the hot junction of the thermopile element 1. It outputs thermoelectromotive force generated according to the temperature difference between the hot junction and the cold junction.

Further, as a conventional ear thermometer using a thermopile sensor as described above, there is an ear thermometer shown in FIG. As shown in Fig. 10, such an ear thermometer includes a main body case 11, a probe 12 positioned at the tip of the main body case 11, an infrared detector 1 housed in the main body case 11 and the probe 12, and so on. 3 and a temperature measurement circuit section 14.

The probe 12 is formed so as to become thinner toward the tip so as not to be inserted deeply into the ear canal, so that the user can use it safely. The infrared detector 13 is composed of a thermopile sensor 15 for detecting infrared rays radiated from the eardrum and a thermopile sensor. And a waveguide 16 connected to the sensor 15 for efficiently transmitting weak infrared rays radiated from the eardrum. The waveguide 16 and the thermopile sensor 15 are fixed to the main body case 11 by support plates 17 and 18, respectively. The temperature measurement circuit section 14 includes a printed circuit board 16 in which a temperature measurement circuit is incorporated, a start switch (not shown), and a liquid crystal temperature display. The thermopile sensor 15 and the printed circuit board 16 are electrically connected.

In the ear thermometer described above, the infrared radiation radiated from the eardrum and taken in from the waveguide 16 is converted into thermal energy by the thermopile sensor 15, and the hot junction and the cold junction of the thermopile sensor 15 are converted. Temperature based on the thermoelectromotive force generated in accordance with the temperature difference between the thermopile sensor and the temperature data of the thermopile sensor 15 detected by a temperature measuring element such as a thermostat attached to the thermopile sensor 15. The measurement circuit performs arithmetic processing, and the temperature of the eardrum is displayed on a liquid crystal display.

Furthermore, as an ear thermometer using the conventional thermopile sensor as described above, the present applicant has proposed a radiation thermometer of PCT / JP98 / 0245. FIG. 11 is a block diagram showing a temperature measuring circuit of a radiation thermometer of PCT / JP98 / 0245.

In FIG. 11, the thermopile sensor 21 provided in the radiation thermometer outputs a voltage depending on the amount of infrared rays radiated from the eardrum and the temperature of the thermopile sensor 21. That is, the thermopile sensor 21 outputs a voltage corresponding to the difference between the temperature of the object to be measured and the temperature of the thermopile sensor 21, and this output is output when the temperature of the object to be measured is higher than the temperature of the thermopile sensor 21. It is output as a positive voltage, and is output as a negative voltage when the temperature of the measurement target is lower than the temperature of the thermopile sensor 21. When the temperature of the thermopile sensor 21 is equal to the temperature of the thermopile sensor 21, the output of the thermopile sensor 21 is 0.

The operational amplifier 22 connected to the thermopile sensor 21 amplifies the minute voltage output from the thermopile sensor 21 to a predetermined magnitude. A comparator (voltage comparator) IC 23 connected to the operational amplifier 22 detects the presence or absence of the output of the thermopile sensor 21 amplified by the operational amplifier 22. That is, the comparator IC 23 is connected to the thermopile sensor irrespective of the magnitude of the output of the thermopile sensor 21 and its sign. A signal is sent to the microcomputer 27 as to whether the output of the sensor 21 is 0 or not.

Mono- Mopairusensa 2 1 profile is a good metal can package 2 5 structure in thermal conductivity, mono- miss evening 2 4 This metal can package 2 5 any installed _c This mono mistake evening 2 Reference numeral 4 denotes a temperature measuring element for measuring the temperature of the thermopile sensor 21 via the metal can package 25, and converts a change in the resistance value in the thermistor 24 due to a change in the temperature of the thermistor 24 into a voltage. And output. The operational amplifier 26 connected to the thermistor 24 amplifies the output of the thermistor 24.

The microcomputer 27 has a built-in AD converter, and the microcomputer 27 performs arithmetic processing based on the output signal from the IC 23 and the output signal from the monitor 24 to perform liquid crystal temperature processing. Send the temperature value output of the measurement target to display 28. The liquid crystal temperature display 28 digitally displays the temperature of the object to be measured.

The heater 29 is wound around a metal can package 25 to heat the thermopile sensor 21. The drive IC 30 transmits a heating command signal from the microcomputer 27 to the microcomputer 29.

The following describes how the temperature of the measurement target is measured by the temperature measurement circuit described above.

In the radiation thermometer of PCT / JP980 / 0205, before the temperature measurement is started, the temperature of the thermopile sensor 21 is set to a preset temperature, for example, about 32 ° C. A heating command signal is sent on evening 29. Therefore, at the start of the temperature measurement, the temperature of the thermopile sensor 21 has risen to the set temperature.

When a command to start temperature measurement is transmitted from the outside to the microcomputer 27, a heating command signal for heating the thermopile sensor 21 with the heating amount per unit time being substantially constant is sent from the microcomputer 27 to the drive IC 30. Is sent to the heater 29 via. During the temperature measurement, the thermopile sensor 21 is heated by open loop control, that is, without changing the heating amount of the heater 29.

When the temperature measurement is started, the thermopile sensor 21 is rapidly heated, and the output of the thermopile sensor 21 decreases rapidly. When heating proceeds and the temperature of the thermopile sensor 21 becomes equal to the temperature of the eardrum to be measured, the output of the thermopile sensor 21 becomes 0. The output signal of the thermopile sensor 21 is sent to the comparator IC 23. The temperature of the thermopile sensor 21 at the time when the output of the thermopile sensor 21 becomes 0 is sent to the microcomputer 27 based on the output from the thermistor 24. By performing arithmetic processing, the temperature of the eardrum to be measured is detected. The detected temperature of the eardrum is recognized by being displayed on the liquid crystal temperature indicator 28.

As described above, the radiation thermometer of PCT / JP 98/0 205 uses the detector with Comparator IC 23 as a detector to detect the output of the thermopile sensor 21. Since the temperature of the thermopile sensor 21 at the time when the output of the thermopile sensor 21 is 0 can be detected by an inexpensive circuit, the temperature at which the temperature of the thermopile sensor 21 is feedback-controlled is reduced. No adjustment is required. Therefore, the radiation thermometer of PCT / JP980 / 0245 can improve the measurement accuracy, shorten the measurement time, and reduce the number of parts. Has advantages.

However, the conventional thermopile sensor shown in FIGS. 8 and 9 and the conventional ear thermometer shown in FIG. 10 have the following problems, and the PC TZJ P98 / There was room for improvement in the radiation thermometer of 0 2 0 4 5 as follows.

In the conventional thermopile sensor shown in FIGS. 8 and 9, since the package 7 has a cylindrical shape as described above, for example, when the thermopile sensor is used in a small electronic device, the thermopile sensor is arranged. The arrangement position was sometimes restricted. In particular, when used in an ear thermometer, the probe 12 becomes thinner toward the tip so as not to be inserted deeply into the ear canal as shown in Fig. 10, so depending on the size of the package 7, a thermopile may be used. Sensor 15 could not be provided at the tip of probe 12. Therefore, in the conventional ear thermometer, it is necessary to provide a waveguide 16 for guiding infrared rays to the thermopile sensor 15 as shown in Fig. 10, and to support the waveguide 16 and the thermopile sensor 15 Support plates 17 and 18 were required. These are not only due to the increased cost of the ear thermometer due to the increase in the number of parts, but also because the distance between the thermopile sensor 15 and the eardrum is so large that the infrared energy attenuates in proportion to the square of the distance. 5 caused a significant drop in sensitivity and output, causing errors and the like. PC P 53

On the other hand, the ear thermometer of PCT / JP98 / 0205 above mentioned above had room for improvement in the following points. That is, in the ear thermometer of PCT / JP980 / 0245, the thermopile sensor 21 is heated by the heater 29 as shown in FIG. Although the temperature of the thermopile sensor 21 has risen to the set temperature, after the temperature measurement is started, the heater 29 is heated to conduct heat to the thermopile sensor 21 via the metal tube package 25 for a certain period of time. Was required. It is an object of the present invention to solve the above-mentioned problems in the prior art and to provide an infrared sensor capable of relaxing the restriction on the arrangement position even when used in a small electronic device.

Another object of the present invention is to provide an inexpensive radiation thermometer with improved measurement accuracy and a reduced number of parts.

It is another object of the present invention to provide a radiation thermometer capable of shortening the measurement time.

DISCLOSURE OF THE INVENTION The infrared sensor according to the first invention provided to solve the above-described problems includes an infrared detecting element, a stem through which an electrode connected to the infrared detecting element is inserted, and an infrared detecting element attached to the stem. An infrared sensor comprising: a package having an infrared receiving window for enclosing the element; and an infrared sensor having: a side surface of the package having a tapered portion in which a diameter of the package on the infrared receiving window side is smaller than a diameter of the stem on the stem side. It is.

With such a configuration, even when used for a small electronic device, the restriction on the arrangement position can be relaxed. In particular, when used in an ear thermometer, the infrared sensor can be placed close to the eardrum because it conforms to the probe shape.

Further, an infrared sensor according to a second invention of the present application provided to solve the above-described problems includes an infrared detecting element, a stem having an electrode connected to the infrared detecting element inserted therethrough, A package provided with an infrared receiving window that is mounted on the system and encloses the infrared detecting element; and an infrared sensor having the above, wherein the package has a truncated cone whose diameter on the infrared receiving window side of the package is smaller than the diameter on the stem side. This is an infrared sensor characterized by having a shape.

With such a configuration, even when used for a small electronic device, the restriction on the arrangement position can be relaxed. In particular, when used in an ear thermometer, the infrared sensor can be arranged near the eardrum because it conforms to the shape of the probe.

Further, a radiation thermometer according to a third invention of the present application provided to solve the above-mentioned problem is characterized in that the infrared sensor according to the first invention of the present application is provided at a probe tip for receiving infrared rays. It is a thermometer.

With this configuration, components such as a waveguide and a support plate for supporting the thermopile sensor become unnecessary, and the distance between the thermopile sensor and the eardrum becomes shorter, so that infrared energy increases in proportion to the square of the distance. As a result, a significant increase in the sensitivity of the thermopile sensor results in a large improvement in output, resulting in an inexpensive high-accuracy radiation thermometer with a small number of components while improving measurement accuracy.

Further, a radiation thermometer according to a fourth invention of the present application provided to solve the above-mentioned problem is characterized in that the infrared sensor according to the second invention of the present application is provided at a probe tip for receiving infrared rays. It is a thermometer.

Further, a radiation thermometer according to a fifth invention of the present application provided to solve the above-mentioned problem is a sensor having an infrared sensor according to the first invention of the present application, and a hollow portion adapted to a taper portion of the infrared sensor. A radiation thermometer comprising: a heating block; a heating device for heating the sensor heating block; and a slide mechanism for sliding the infrared sensor with respect to the sensor heating block. is there. With this configuration, the infrared sensor can be heated by sliding the infrared sensor on a pre-heated sensor heating block, so that the measurement time can be shortened with the shortened heating time.

Further, a radiation thermometer according to a sixth aspect of the present invention provided to solve the above-mentioned problem is a sensor having a infrared sensor according to the second invention of the present application, and a hollow portion adapted to the truncated cone shape of the infrared sensor. A radiation thermometer comprising: a heating block; a heating device that heats the sensor heating block; and a slide mechanism that slides the infrared sensor with respect to the sensor heating block. is there.

With this configuration, the infrared sensor can be heated by sliding the infrared sensor on a pre-heated sensor heating block, so that the measurement time can be shortened with the shortened heating time.

Further, a radiation thermometer according to a seventh invention of the present application provided to solve the above-mentioned problems includes an infrared sensor according to the first invention of the present application, a heating device for heating the infrared sensor, and a tapered portion of the infrared sensor. A radiation thermometer, comprising: a sensor heat radiation block having a hollow portion conforming to the above; and a slide mechanism for sliding the infrared sensor with respect to the sensor heat radiation block.

By adopting such a configuration, it is possible to slide the pre-heated infrared sensor on the sensor radiating block and cool the sensor. For example, the infrared sensor is cooled more than the case where the pre-heated infrared sensor is cooled by natural heat radiation. Cooling (temperature adjustment) in a short time. Therefore, measurement time can be reduced.

In addition, a radiation thermometer according to an eighth invention of the present application provided to solve the above-mentioned problems includes an infrared sensor according to the second invention of the present application, a heating device for heating the infrared sensor, and a truncated cone of the infrared sensor. A radiation thermometer, comprising: a sensor heat radiation block having a hollow portion conforming to a shape; and a slide mechanism for sliding the infrared sensor with respect to the sensor heat radiation block.

By adopting such a configuration, it is possible to slide the pre-heated infrared sensor on the sensor radiating block and cool the sensor. For example, the infrared sensor is cooled more than the case where the pre-heated infrared sensor is cooled by natural heat radiation. Cooling (Temperature adjustment) can be performed in a short time. Therefore, measurement time can be reduced.

Further, a radiation thermometer according to a ninth invention of the present application provided to solve the above-mentioned problem is a radiation thermometer according to the seventh or eighth invention of the present application, wherein the heating device uses a Peltier element. The radiation thermometer is a thermo module having a heating surface and a cooling surface, wherein the heating surface is connected to the infrared sensor, and the cooling surface is connected to the sensor radiating block.

With this configuration, it is possible to previously heat the infrared sensor and simultaneously cool the sensor radiation block. Therefore, cooling (temperature adjustment) of the infrared sensor can be performed in a shorter time. Therefore, the measurement time can be further reduced.

The radiation thermometer according to the fifth to ninth aspects of the present invention has the above-described configuration, and the infrared sensor in the shape of a taper or a truncated cone is housed at the probe tip. The maximum contact area can be obtained by simply sliding the sensor heating block or the sensor heat radiation block having the same taper hollow portion as that of a small distance. Therefore, the maximum heating or heat radiation effect can be obtained with the minimum slide amount.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a thermopile sensor according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a thermopile sensor according to one embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view showing a radiation thermometer according to one embodiment of the present invention.

FIG. 4 is a perspective view showing a slide mechanism of the radiation thermometer according to one embodiment of the present invention.

FIG. 5 is a block diagram showing a temperature measuring circuit of the radiation thermometer according to one embodiment of the present invention. FIG.

FIG. 6 is a perspective view showing a slide mechanism of a radiation thermometer according to another embodiment of the present invention.

FIG. 7 is a perspective view showing a heating device for a radiation thermometer according to another embodiment of the present invention.

FIG. 8 is a sectional view showing a conventional thermopile sensor.

FIG. 9 is a perspective view showing a conventional thermopile sensor.

FIG. 10 is a sectional view showing a conventional radiation thermometer.

FIG. 11 is a block diagram showing a temperature measuring circuit of a conventional radiation thermometer.

Explanation of reference numerals

4 5 Stem

4 7 Package

5 4 Sensor heating block

5 5 Thermopile sensor

5 9 Slide mechanism

7 2 Sensor heat radiation work

7 4 Thermo module

7 5 Peltier element

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

The infrared sensor according to one embodiment of the present invention is a thermopile sensor, and as shown in FIG. 1, a thermopile element 41 for receiving infrared rays and a thermopile element 41 are formed on the surface by vapor deposition or the like. Heat sink 4 2 and thermopile element 4 1 The thermocouple comprises electrode pins 43 and 44 electrically connected to the thermocouple, a stem 45 passing through the electrode pins 43 and 44, and a package 47 having an infrared receiving window 46.

The package 47 is formed of a steel plate or the like, and has a hollow truncated cone shape as shown in FIG. 2, and a stem 45 formed of a steel plate or the like is attached to one end of the package 47. The infrared receiving window 46 is attached to the other end. Also, the diameter of the package 47 on the side of the infrared receiving window 46 is smaller than the diameter of the stem 45 on the side. The thermopile element 41 has a circular shape, and although not shown, a hot junction for receiving infrared rays is provided at the center thereof, and a cold junction is provided around the center.

In the thermopile sensor according to the present embodiment, the infrared light from the measurement object incident from the infrared light receiving window 46 provided in the package 47 enters the warm junction of the thermopile element 41, thereby Radiant energy is converted to heat energy, and a thermoelectromotive force is generated that is generated according to the temperature difference between the hot junction and the cold junction.

As described above, in the thermopile sensor according to the present embodiment, the package 47 has the shape of a truncated cone, so that the restriction on the arrangement position is relaxed even when used in a small electronic device. can do. In particular, when used in an ear thermometer, it fits the shape of the probe, so this thermopile sensor can be placed near the eardrum. Therefore, components such as a waveguide and a support plate for supporting the thermopile sensor are not required, and the distance between the thermopile sensor and the eardrum is short, so that the infrared energy increases in proportion to the square of the distance. The drastic improvement in the sensitivity of the thermopile sensor leads to a large increase in output, which results in an inexpensive high-accuracy radiation thermometer with a small number of components while improving measurement accuracy.

Next, a radiation thermometer according to an embodiment of the present invention will be described with reference to the drawings. The radiation thermometer according to one embodiment of the present invention is an ear thermometer, and as shown in FIG. 3, a main body case 51, an infrared detecting section 52 housed in the main body case 51, and a temperature measurement circuit. And 53 parts. The infrared detector 52 includes a sensor heating block 54 and a thermopile sensor 55.The temperature measuring circuit 53 includes printed circuit boards 56a and 56b, a switch 57, and a liquid crystal temperature display 5. 8 and a slide mechanism 59.

Main body case 51 inserted into the ear canal The probe 60 at the tip must not be inserted deeply into the ear canal. It is formed so that it becomes thinner toward the tip so that the user can use it safely. The infrared detector 5 2 is placed in the main body case 5 1 end of the probe 6 in 0, _c infrared detector 5 2 for detecting the infrared radiation incident from provided hole on the tip of the probe 6 0, the radiation from the tympanic membrane It has a frusto-conical thermopile sensor 55 that detects the infrared rays that are emitted, and a hollow part that houses the thermopile sensor 55 inside, and has a hole at the tip end for taking in infrared rays. And a sensor heating block 5 having a truncated cone shape. The electrode pins 61 of the thermopile sensor 55 are connected to the printed circuit board 56 a, and the sensor heating probe 54 is fixed to the probe 60. As shown in FIG. 3, a thermopile sensor 55 and a printed circuit board 56a can be slid on the sensor heating block 54 in the longitudinal direction of the main body case 51 as shown in FIG. As described above, the small holes 62 for holding the electrode pins 61 of the thermopile sensor 55 are provided. In addition, sensor heating block

54 is provided with a heating device such as a heater (not shown), and when a heating command signal from the temperature measurement circuit is transmitted from the cable 63 to the sensor heating block 54 over a period of time, the sensor heating block 5 4 is heated. Further, when the thermopile sensor 55 and the printed board 56a are advanced toward the front end of the main body case 51 by the slide mechanism 59 described below, the thermopile sensor 55 The inner peripheral surface of the sensor heating block 54 is hollowed out into a truncated conical shape so that the inner peripheral surface of the sensor heating block 54 contacts each other.

On the other hand, the temperature measurement circuit section 5 3 is a printed circuit board 5 with a built-in temperature measurement circuit.

6a and 56b, a switch 57 and a liquid crystal temperature indicator 58 directly attached to the printed circuit board 56b, and a slide mechanism 59 are provided. The printed circuit board 56b is fixed to the main body case 51, and the printed circuit boards 56a and 56b are connected by a spring 64 and a cable 65 as shown in FIG. The switch 57 and the liquid crystal temperature display 58 are exposed to the outside of the main body case 51 through holes provided in the main body case 51, respectively. Pressing the switch 57 starts the temperature measurement, and the LCD temperature display 58 digitally displays the measured temperature.

The slide mechanism 59 includes electromagnets 66a and 66b provided on the opposing surfaces of the printed circuit boards 56a and 56b, respectively, and printed circuit boards 56a and 56b. Concatenate Spring 64. Normally, the thermopile sensor 55 and the printed board 56 a are urged in the direction of the printed board 56 b by the elastic force of the spring 64. In such a case, the thermopile sensor 55 is located at a small distance from the sensor heating block 54 as shown in FIG. 4 (a). At the time of temperature measurement, by energizing the electromagnets 66a and 66b, the thermopile sensor 55 and the printed circuit board 56a are urged in the sensor heating block 54 direction due to the repulsion by electromagnetic induction. As shown in FIG. 4 (b), the thermopile sensor 55 comes into contact with the sensor heating block 54. After the temperature measurement, when the power to the electromagnets 66a and 66b is released, the thermopile sensor 55 and the printed circuit board 56a are attached in the direction of the printed circuit board 56b by the elastic force of the spring 64. Returned to the original position.

Here, the temperature measurement circuit will be described with reference to the block circuit diagram of FIG. In FIG. 5, the thermopile sensor 55 provided in the ear thermometer outputs a voltage that depends on the amount of infrared radiation radiated from the eardrum and the temperature of the thermopile sensor 55. That is, the thermopile sensor 55 outputs a voltage corresponding to the difference between the temperature of the measurement target and the temperature of the thermopile sensor 55, and the output is such that the temperature of the measurement target is higher than the temperature of the thermopile sensor 55. In this case, it is output as a positive voltage, and when the temperature of the measurement target is lower than the temperature of the thermopile sensor 55, it is output as a negative voltage. When the temperature of the measurement target is equal to the temperature of the thermopile sensor 55, the output of the thermopile sensor 55 becomes 0.

The operational amplifier 67 connected to the thermopile sensor 55 amplifies the small voltage output from the thermopile sensor 55 to a predetermined magnitude. A comparator (voltage comparator) IC 68 connected to the operational amplifier 67 detects the presence or absence of the output of the thermopile sensor 55 amplified by the operational amplifier 67. That is, the comparator IC 68 sends a signal to the microcomputer 69 whether or not the output of the thermopile sensor 55 is 0, regardless of the magnitude of the output of the thermopile sensor 55 and whether the output is positive or negative.

Although not shown, the temperature of the thermopile sensor 55 is output as a voltage due to a change in the resistance value of a temperature measuring element such as a thermometer attached to the thermopile sensor 55. An operational amplifier 70 connected to the thermopile sensor 55 amplifies the output from the temperature measuring element. The microcomputer 69 has a built-in AD converter, and the microcomputer 69 performs arithmetic processing based on the output signal from the comparator IC 68 and the output signal from the operational amplifier 70, and outputs the result to the liquid crystal temperature display 58. Sends the temperature value output of the measurement target. The liquid crystal temperature display 58 digitally displays the temperature of the object to be measured.

The drive IC 71 transmits a heating command signal from the microcomputer 69 to a sensor heating block 54 having a heater.

How the eardrum temperature is measured by the ear thermometer according to the present embodiment described above will be described.

In the ear thermometer according to the present embodiment, the sensor heating block 54 is heated from the micro computer 69 so that the temperature of the sensor heating block 54 becomes a preset temperature, for example, about 45 ° C before the temperature measurement is started. A heating command signal is sent to the block 54. Therefore, at the start of temperature measurement, the temperature of the sensor heating block 54 has risen to the set temperature.

When a command to start temperature measurement is transmitted from the outside to the microcomputer 69, the slide mechanism 59 operates, and the thermopile sensor 55 comes into contact with the sensor heating work 54 as described above. Then, the thermopile sensor 55 is rapidly heated by the heat conducted from the preheated sensor heating block 54, and the output of the thermopile sensor 55 decreases rapidly. When the heating proceeds and the temperature of the thermopile sensor 55 becomes equal to the temperature of the eardrum to be measured, the output of the thermopile sensor 55 becomes 0. Since the output signal of the thermopile sensor 55 is sent to the micro computer 69 by the comparator IC 68, the temperature of the thermopile sensor 55 at the time when the output of the thermopile sensor 55 becomes 0 is obtained. The microphone computer 69 performs arithmetic processing based on the output from the temperature measuring element to detect the temperature of the eardrum to be measured. The detected temperature of the eardrum is recognized by being displayed on the liquid crystal temperature indicator 58.

As described above, the ear-type thermometer according to the present embodiment provides the waveguide and the thermopile sensor by providing the truncated cone-shaped thermopile sensor 55 at the tip of the case body 51. The need for supporting plates and other components is eliminated, and the distance between the thermopile sensor and the eardrum is reduced, so the infrared energy increases in proportion to the square of the distance. As a result, a significant improvement in the sensitivity of the thermopile sensor leads to a large increase in output, resulting in an inexpensive high-accuracy radiation thermometer with a small number of components while improving measurement accuracy.

A thermopile sensor 55 having a truncated cone shape, a sensor heating block 54 having a hollow portion conforming to the truncated cone shape, a heating device for heating the sensor heating block 54, and a slide mechanism 5 With the provision of (9), the thermopile sensor 55 can be heated by sliding the thermopile sensor 55 on the pre-heated sensor heating block 54, so that the measurement time can be reduced as the heating time is reduced. .

Further, with the above configuration, the maximum contact area can be obtained only by sliding the frusto-conical thermopile sensor 55 to the sensor heating block 54 by a small distance. Therefore, the maximum heating or heat radiation effect can be obtained with the minimum slide amount.

In the ear thermometer according to the present embodiment, the slide mechanism is the slide mechanism 59 using the electromagnets 66 a and 66 b and the spring 64, but is not limited thereto. Alternatively, for example, a manual slide mechanism that manually slides the thermopile sensor with respect to the sensor heating block may be used. Even with such a manual slide mechanism, the maximum contact area can be obtained simply by sliding the frusto-conical thermopile sensor 55 to the sensor heating block 54 a small distance. Is received. Therefore, the maximum heating or heat radiation effect can be obtained with the minimum slide amount.

Next, another embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG. However, description of the same parts as those of the above-described embodiment will be omitted, and only different parts will be described.

A radiation thermometer according to another embodiment of the present invention is an ear thermometer, and the sensor heating block 54 in the ear thermometer described above does not include a heating device and has a sensor heat radiation block 72. Has become. The heating device is attached to the thermopile sensor 55. For example, as shown in FIG. 6, a heating device 73 is wound around the outer peripheral surface of the thermopile sensor 55. In addition, the cable 63 in the ear thermometer described above is unnecessary.

In the ear thermometer according to the present embodiment, the temperature of the thermopile sensor 55 is a preset temperature, for example, about 42 ° C. before the start of temperature measurement.

The slide mechanism 59 is activated by the instruction to start temperature measurement, and the thermopile sensor 55 Contacts the heat dissipation block 72 of the sensor. Then, the heat of the thermopile sensor 55 is conducted to the sensor heat dissipating block 72, whereby the heat is rapidly dissipated, and the output of the thermopile sensor 55 increases rapidly. When the heat radiation proceeds and the temperature of the thermopile sensor 55 becomes equal to the temperature of the eardrum to be measured, the output of the thermopile sensor 55 becomes 0. Thereafter, the temperature of the eardrum to be measured is detected in the same procedure as the ear thermometer described above.

In the ear thermometer according to the present embodiment, the heating device attached to the thermopile sensor 55 is such that the heating device 73 is wound on the outer peripheral surface of the thermopile sensor 55 as described above. The invention is not limited to this. For example, a heating element or the like may be provided inside the package of the thermopile sensor 55. Further, for example, a thermo module using a Peltier element may be used.

Here, an embodiment in which a thermo module is attached as a heating device will be described with reference to FIG. FIG. 7A is a perspective view showing a thermo module 74 attached to the ear thermometer according to the present embodiment, and FIG. 7B is a perspective view showing the thermo module 74 with the thermo module 74. FIG. 6 is a perspective view showing a state where the display unit is attached to a fifth embodiment. In FIG. 7 (b), for the sake of convenience, the bottom of the truncated cone-shaped sensor heat-dissipating block 72 is omitted.

As shown in FIG. 7 (a), the thermo module 74 has a Peltier element 75 and lead wires 76. The upper surface of the Peltier element 75 has a cooling surface 77, and the lower surface has a heating surface 78. Has become. The Peltier element 75 is an element having a property of absorbing heat on the cooling surface 77 and releasing heat from the heating surface 78 by the Peltier effect when energized. In the ear thermometer according to the present embodiment, as shown in FIG. 7 (b), the heating surface 78 of the Peltier element 75 is adhered almost to the center of the stem 45 of the thermopile sensor 55, and cooling is performed. The tip 80 of the flat plate 79 attached to the surface 77 is adhered to the inner peripheral surface of the sensor heat radiation block 72. The lead wire 76 is connected to the printed circuit board 56a. The flat plate 79 is formed of a metal having good heat conductivity, and has elasticity so as not to hinder the slide of the thermopile sensor 55.

In the ear thermometer to which the thermo module 74 shown in FIG. 7 is attached, the Peltier element is simultaneously heated when the thermopile sensor 55 is preheated before the temperature measurement is started. CT / JP98 / 04653

The cooling surface 7 7 absorbs the heat of the sensor radiating block 72 through the flat plate 79, that is, cools the sensor radiating block 72, so the sensor radiating block 72 must be Can be kept cool. Therefore, when the thermopile sensor 55 is in contact with the sensor heat radiation block 72 when the slide mechanism 59 is activated by the instruction to start temperature measurement, the thermopile sensor 55 can be cooled efficiently in a short time. .

As described above, the ear thermometer according to the present embodiment includes a frusto-conical thermopile sensor 55, a heating device for heating the thermopile sensor 55, and a hollow portion adapted to the frusto-conical shape. By having the sensor heat dissipating block 72 having the following and the slide mechanism 59, the preheated thermopile sensor 55 can be cooled by sliding it on the sensor heat dissipating block 59. The thermopile sensor can be cooled (temperature adjusted) in a shorter time than when the previously heated thermopile sensor is cooled by natural heat radiation. Therefore, the measurement time can be shortened.

Also, if the heating device is a thermo module using a Peltier element, the heating surface of the thermo module is connected to the thermopile sensor 55, and the cooling surface is connected to the sensor radiation block 72. 5 can be heated and at the same time, the sensor heat radiation process 72 can be cooled. Therefore, cooling (temperature adjustment) of the thermopile sensor 55 can be performed in a shorter time. Therefore, the measurement time can be further reduced.

Claims

The scope of the claims

1. An infrared sensor having: a package having an infrared detecting element, a stem through which an electrode connected to the infrared detecting element is inserted, and an infrared receiving window attached to the stem and enclosing the infrared detecting element; An infrared sensor, characterized in that the side surface has a taper section in which the diameter of the package on the infrared light receiving window side is smaller than the diameter of the stem side.

2. An infrared sensor comprising: an infrared detection element; a stem having an electrode connected to the infrared detection element inserted therethrough; and a package having an infrared receiving window attached to the stem and enclosing the infrared detection element. However, the infrared sensor has a truncated cone shape in which the diameter of the package's infrared light receiving window is smaller than the diameter of the stem.

3. A radiation thermometer, wherein the infrared sensor according to claim 1 is provided at a tip of a probe that receives infrared rays.

4. A radiation thermometer, wherein the infrared sensor according to claim 2 is provided at a tip of a probe that receives infrared rays.

5. The infrared sensor according to claim 1, a sensor heating block having a hollow portion adapted to a tapered portion of the infrared sensor, a heating device for heating the sensor heating block, and the infrared sensor as the sensor. A radiation thermometer, comprising: a sliding mechanism for sliding the heating block.

6. The infrared sensor according to claim 2, a sensor heating block having a hollow portion adapted to the truncated cone shape of the infrared sensor, a heating device for heating the sensor heating block, and the infrared sensor. A radiation thermometer, comprising: a slide mechanism for sliding the sensor heating block.

7. The infrared sensor according to claim 1, a heating device for heating the infrared sensor, a sensor heat radiation block having a hollow portion that fits a tapered portion of the infrared sensor, and the sensor heat radiation block. A radiation mechanism, comprising: a slide mechanism that slides a pressure sensor;

8. The infrared sensor according to claim 2, a heating device that heats the infrared sensor, a sensor heat dissipation block having a hollow portion that fits the truncated cone shape of the infrared sensor, and the sensor for heat dissipation of the sensor. A radiation thermometer comprising: a slide mechanism for sliding a block; and a slide mechanism.

9. The heating device is a thermo module using a Peltier element having a heating surface and a cooling surface, wherein the heating surface is connected to the infrared sensor, and the cooling surface is connected to the sensor heat dissipation block. The radiant temperature according to claim 7 or 8, wherein