JP3346583B2 - Infrared sensor and radiation thermometer - Google Patents

Description

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

BACKGROUND ART Conventionally, infrared rays emitted from a measurement target are detected by using a radiation thermometer, and the temperature of the measurement target is measured in a non-contact manner. 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 a non-contact ear thermometer that measures body temperature by detecting infrared rays is increasing.

One of the reasons why ear-type thermometers have attracted attention is that the eardrum is located deep in the human body and is less susceptible to the external environment, so it 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. A pyroelectric sensor is a sensor that detects, as an output, a change in surface charge of a pyroelectric body due to a temperature change when absorbing infrared energy radiated from a measurement target. The pyroelectric sensor outputs an output only when the temperature of the pyroelectric body changes. Therefore, the incident infrared ray is chopped and intermittently cut off to obtain a continuous output. On the other hand, a thermopile sensor is a sensor in which thermocouples are deposited using an integrated circuit technology, and a continuous output corresponding to a temperature difference between a hot junction and a cold junction is taken out by a large number of directly connected thermocouples.

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

As a thermopile sensor applied to a conventional ear thermometer, for example, there is a thermopile sensor shown in FIG. 10 and FIG. As shown in FIG. 10, such a thermopile sensor includes a thermopile element 1 for receiving infrared rays,
A heat sink 2 having a thermopile element 1 formed on its surface by vapor deposition or the like; electrode pins 3 and 4 electrically connected to a thermocouple of the thermopile element 1; a stem 5 having the electrode pins 3 and 4 inserted therein; A package 7 having a window 6.

The package 7 has a hollow cylindrical shape as shown in FIG. 11, and has a stem 5 attached to one end and an infrared receiving window 6 attached to the other end. The thermopile element 1 is circular, 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.

The above-described thermopile sensor converts infrared radiation energy into thermal energy by converting infrared radiation from the measurement target incident from the infrared light receiving window 6 provided in the package 7 to the hot junction of the thermopile element 1, and A thermoelectromotive force generated according to a temperature difference between the contact portion and the cold contact portion is output.

Further, as a conventional ear thermometer using the thermopile sensor as described above, there is an ear thermometer shown in FIG. Such an ear thermometer, as shown in FIG. 12,
It comprises a main body case 11, a probe 12 located at the tip of the main body case 11, an infrared detecting section 13 housed in the main body case 11 and the probe 12, and a temperature measurement circuit section.

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 a thermopile sensor 15 that detects infrared rays emitted from the eardrum,
A waveguide 16 is connected to the thermopile sensor 15 for efficiently transmitting weak infrared rays emitted 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. Note that 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 a thermopile sensor 15.
The thermopile is converted into thermal energy, and is generated according to the temperature difference between the hot junction part and the cold junction part of the thermopile sensor 15 and a thermopile detected by a temperature measuring element such as a thermistor attached to the thermopile sensor 15. Based on the temperature data of the sensor 15, the temperature measurement circuit performs arithmetic processing, and the temperature of the eardrum is displayed on the liquid crystal temperature display on a liquid crystal display.

Further, as an ear thermometer using the conventional thermopile sensor as described above, the applicant of the present invention has published PCT / JP98 / 0
A 2045 radiation thermometer has been proposed. Fig. 13 shows PCT / JP98 / 0
It is a block diagram which shows the temperature measurement circuit of the radiation thermometer of 2045.

In FIG. 13, 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 measurement target and the temperature of the thermopile sensor 21,
This output is output as a positive voltage when the temperature of the measurement target is higher than the temperature of the thermopile sensor 21, 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 object to be measured is equal to the temperature of the thermopile sensor 21, the output of the thermopile sensor 21 becomes zero.

The operational amplifier 22 connected to the thermopile sensor 21
The small voltage output from the thermopile sensor 21 is amplified to a predetermined magnitude. A comparator (voltage comparator) IC23 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 IC23 is connected to the thermopile sensor irrespective of the magnitude of the output of the thermopile sensor 21 and the sign thereof.
A signal indicating whether or not the output of 21 is 0 is sent to the microcomputer 27.

The outer shape of the thermopile sensor 21 has a metal can package 25 having excellent heat conductivity, and the thermistor 24 is attached to the metal can package 25. The thermistor 24 is 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 outputs the voltage. . An 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 comparator IC 23 and the output signal from the thermistor 24 and sends the temperature value output of the measurement target to the liquid crystal temperature display 28. . The liquid crystal temperature display 28 digitally displays the temperature of the measurement target.

The heater 29 is wound around the metal can package 25 to heat the thermopile sensor 21. Drive IC30
Is a heater command signal from the microcomputer 27
Communicate to 29.

How the temperature of the measurement target is measured by the temperature measurement circuit described above will be described.

In the radiation thermometer of PCT / JP98 / 02045, a heating command signal is sent from the microcomputer 27 to the heater 29 so that the temperature of the thermopile sensor 21 becomes a preset temperature, for example, about 32 ° C. before the temperature measurement is started. Therefore, at the start of temperature measurement, the temperature of the thermopile sensor 21 has risen to the set temperature.

An instruction to start temperature measurement is issued from an external microcomputer.
When transmitted to the heater 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 heater 29 via the drive IC 30. Further, 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 rapidly decreases. When the 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. Since the output signal of the thermopile sensor 21 is sent to the microcomputer 27 by the comparator IC23, the temperature of the thermopile sensor 21 at the time when the output of the thermopile sensor 21 becomes 0 is based on the output from the thermistor 24. The microcomputer 27 performs arithmetic processing to detect the temperature of the eardrum to be measured. The detected eardrum temperature is a liquid crystal temperature indicator
Recognized by being displayed by 28.

As described above, the radiation thermometer of PCT / JP98 / 02045 uses the detection device having the comparator IC23 as the detection device for detecting the presence or absence of 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, there is no need for a temperature adjusting means for feedback-controlling the temperature of the thermopile sensor 21. Therefore, the radiation thermometer of PCT / JP98 / 02045 has the advantages that the measurement accuracy can be improved, the measurement time can be shortened, and the number of parts can be reduced.

However, the conventional thermopile sensor shown in FIGS. 10 and 11 and the conventional ear thermometer shown in FIG.
Due to the following problems, the PCT / JP98 / 02045 radiation thermometer shown in Fig. 13 has room for improvement as follows.

In the conventional thermopile sensor shown in FIGS. 10 and 11, 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 arrangement position of the thermopile sensor is There were cases where it was restricted. In particular, when used in an ear thermometer, as shown in FIG. 12, the probe 12 becomes thinner toward the tip so as not to be inserted deeply into the ear hole. It could not be provided at the tip. 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. 12, and support plates 17, 18 and the like for supporting the waveguide 16 and the thermopile sensor 15 are provided. Was needed. In addition to the increased cost of the ear thermometer due to the increase in the number of parts, 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, resulting in a significant sensitivity of the thermopile sensor 15 Lowering the output,
This is a factor that causes errors and the like.

On the other hand, the ear thermometer of PCT / JP98 / 02045 mentioned above has room for improvement in the following points. That is, PC
In the ear thermometer of T / JP98 / 02045, 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 at the start of temperature measurement, the heater 29
It takes a certain period of time for the heat to be transmitted to the thermopile sensor 21 via the metal tube package 25 and to be transferred to the thermopile sensor 21.

The present invention solves the above-mentioned problems in the prior art, and includes an infrared sensor capable of relaxing the restriction of the arrangement position, even when used in a small electronic device, to improve measurement accuracy, and It is an object of the present invention to provide a radiation thermometer that has a small number of points, is inexpensive, and in particular, can shorten the measurement time.

DISCLOSURE OF THE INVENTION An infrared sensor according to a first invention of the present application 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 having a package with an infrared receiving window for enclosing the infrared sensor, a block for heating the infrared sensor having a hollow portion, a heating device for heating the block for heating the infrared sensor, and heating the infrared sensor to the infrared sensor. And a slide mechanism for sliding with respect to the application block.

With this configuration, since the infrared sensor can be heated by sliding the infrared sensor on the sensor heating block that has been heated in advance, the measurement time can be reduced as the heating time is reduced.

Further, a radiation thermometer according to a second aspect of the present invention 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, and an infrared detecting element attached to the stem. A heating device for heating the infrared sensor, a sensor heat-dissipating block having a hollow portion, and sliding the infrared sensor with respect to the sensor heat-dissipating block. And a slide mechanism for causing the radiation thermometer to be provided.

By adopting such a configuration, it is possible to slide the pre-heated infrared sensor to the sensor heat radiation block and cool it down. Cooling (temperature adjustment) can be performed in a short time. Therefore, the measurement time can be reduced.

An infrared sensor according to a third aspect of the present 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 mounted on the stem to encapsulate the infrared detecting element. The side surface of the package provided with the infrared receiving window has a hollow portion which fits the tapered portion of the radiation thermometer provided with the infrared sensor having a tapered portion in which the diameter of the infrared receiving window side of the package is smaller than the diameter of the stem side. A radiation thermometer comprising a sensor 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.

With such a configuration, even when the electronic device is used for a small electronic device, the restriction on the arrangement position can be relaxed. In particular, when the infrared sensor is used for an ear thermometer, the infrared sensor can be arranged at a position close to the eardrum because it conforms to the shape of the probe. In addition, with such a configuration, the infrared sensor can be slid to the previously heated sensor heating block to heat the sensor, so that the measurement time can be shortened as the heating time is shortened.

An infrared sensor according to a fourth aspect of the present invention, which is provided to solve the above 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. A hollow part that fits the cone or truncated pyramid shape of a radiation thermometer equipped with an infrared sensor that is a cone or truncated pyramid with the diameter of the infrared receiving window side of the package with the infrared receiving window to be enclosed smaller than the diameter of the stem side A radiation thermometer comprising a sensor 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.

With such a configuration, even when the electronic device is used for a small electronic device, the restriction on the arrangement position can be relaxed. In particular, when the infrared sensor is used for an ear thermometer, the infrared sensor can be arranged at a position close to the eardrum because it conforms to the shape of the probe. In addition, if a truncated pyramid shape is adopted, it is possible to prevent the infrared sensor from rotating at the arrangement position. In addition, with such a configuration, the infrared sensor can be slid to the previously heated sensor heating block to heat the sensor, so that the measurement time can be shortened as the heating time is shortened.

Further, a radiation thermometer according to a fifth aspect of the present invention provided to solve the above-described problems includes an infrared detecting element, a stem having an electrode connected to the infrared detecting element inserted therein, and an infrared detecting element attached to the stem. Of a radiation thermometer provided with an infrared sensor having a tapered portion in which the diameter of the package on the side of the infrared receiving window is smaller than the diameter of the stem on the side of the package having the infrared receiving window for enclosing the package. A radiation temperature, comprising: a device, a sensor heat-dissipating block having a hollow portion adapted to the tapered portion of the infrared sensor, and a slide mechanism for sliding the infrared sensor with respect to the sensor heat-dissipating block. It is total.

With such a configuration, even when the electronic device is used for a small electronic device, the restriction on the arrangement position can be relaxed. In particular, when the infrared sensor is used for an ear thermometer, the infrared sensor can be arranged at a position close to the eardrum because it conforms to the shape of the probe. In addition, by adopting such a configuration, the pre-heated infrared sensor can be slid to the sensor heat radiation block and cooled, so that, 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 sixth aspect of the present invention provided to solve the above 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. A heating device for heating the infrared sensor of the radiation thermometer including an infrared sensor having a cone or truncated pyramid shape in which the diameter of the infrared light receiving window side of the package having the infrared light receiving window enclosing is smaller than the diameter of the stem side, A radiation thermometer, comprising: a sensor heat radiation block having a hollow portion conforming to the truncated cone shape of the infrared sensor; and a slide mechanism for sliding the infrared sensor with respect to the sensor heat radiation block. is there.

With such a configuration, even when the electronic device is used for a small electronic device, the restriction on the arrangement position can be relaxed. In particular, when the infrared sensor is used for an ear thermometer, the infrared sensor can be arranged at a position close to the eardrum because it conforms to the shape of the probe. In addition, if a truncated pyramid shape is adopted, it is possible to prevent the infrared sensor from rotating at the arrangement position. In addition, by adopting such a configuration, the infrared sensor that has been heated in advance can be cooled by sliding the sensor on the sensor heat radiation block.
The cooling (temperature adjustment) of the infrared sensor can be performed in a shorter time than when the previously heated infrared sensor is cooled by natural heat radiation. Therefore, the measurement time can be reduced.

Further, in the above radiation thermometer, the heating device,
A thermo module using a Peltier element and 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 radiation block.

With this configuration, it is possible to heat the infrared sensor in advance 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.

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

FIG. 2 is a perspective view showing a thermopile sensor applied to the radiation thermometer 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. 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 an external view of a radiation thermometer module using a thermopile sensor according to still another embodiment of the present invention as viewed from the side.

FIG. 9 is a configuration diagram of a radiation thermometer module using a thermopile sensor according to still another embodiment of the present invention.

FIG. 10 is a sectional view showing a conventional thermopile sensor.

FIG. 11 is a perspective view showing a conventional thermopile sensor.

 FIG. 12 is a sectional view showing a conventional radiation thermometer.

FIG. 13 is a block diagram showing a temperature measuring circuit of a conventional radiation thermometer.

EXPLANATION OF SYMBOLS 45 Stem 47 Package 54 Sensor heating block 55 Thermopile sensor 59 Slide mechanism 72 Sensor heat dissipation block 74 Thermo module 75 Peltier element BEST MODE FOR CARRYING OUT THE INVENTION One embodiment of the present invention is described below with reference to the drawings. It will be described with reference to FIG.

The infrared sensor applied to the radiation thermometer according to one embodiment of the present invention is a thermopile sensor, and as shown in FIG. 1, a thermopile element 41 that receives infrared light,
A heat sink 42 having a thermopile element 41 formed on its surface by vapor deposition or the like, electrode pins 43 and 44 electrically connected to a thermocouple of the thermopile element 41, a stem 45 inserted through the electrode pins 43 and 44, and an infrared light receiving element. Package with window 46
Consists of 47.

The package 47 is formed of a steel plate or the like, 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. 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 of the stem 45. 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 applied to the radiation thermometer according to the present embodiment, infrared rays from the measurement object incident from the infrared light receiving window 46 provided in the package 47 enter the hot junction of the thermopile element 41, Radiant energy is converted into heat energy, and a thermoelectromotive force generated according to a temperature difference between the hot junction and the cold junction is output.

As described above, the thermopile sensor applied to the radiation thermometer according to the present embodiment can be arranged even when used in a small electronic device because the package 47 has a truncated cone shape. Position restrictions can be relaxed. In particular, when the thermopile sensor is used for an ear thermometer, the thermopile sensor can be arranged at a position close to the eardrum because it conforms to the shape of the probe. Therefore, parts such as a support plate for supporting the waveguide and the thermopile sensor are not required, and since the distance between the thermopile sensor and the eardrum is short, the infrared energy increases in proportion to the square of the distance, and as a result, the thermopile A large increase in the sensitivity of the sensor leads to a large increase in output, resulting in an improvement in measurement accuracy and an inexpensive high-accuracy radiation thermometer with a small number of components.

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 measuring circuit section.
53. The infrared detecting section 52 includes a sensor heating block 54 and a thermopile sensor 55, and the temperature measuring circuit section 53 includes printed circuit boards 56a and 56b and a switch 57.
, A liquid crystal temperature indicator 58, and a slide mechanism 59.

The probe 60 at the tip of the main body case 51 inserted into the ear canal,
Since it is formed so as to become thinner toward the tip so as not to be inserted deeply into the ear canal, the user can use it safely. Further, the infrared detecting section 52 is disposed in the probe 60 at the tip of the main body case 51, and detects infrared rays incident from a hole provided at the tip of the probe 60.

The infrared detector 52 has a frusto-conical thermopile sensor 55 for detecting infrared radiation emitted from the eardrum, and a hollow portion for housing the thermopile sensor 55 therein, and has a hole at the tip for taking in infrared light. It comprises a sensor heating block 54 having a truncated cone shape with excellent thermal conductivity. Electrode pins 61 of thermopile sensor 55 are connected to printed circuit board 56a, and sensor heating block 54 is fixed to probe 60. As shown in FIG. 3, the sensor heating block 54 has a thermopile sensor on its bottom surface.
Small holes 62 for holding the electrode pins 61 of the thermopile sensor 55 are provided so that the 55 and the printed board 56a can slide in the longitudinal direction of the main body case 51.
In addition, a heating device such as a heater (not shown) is provided in the sensor heating block 54, and a heating command signal from the temperature measurement circuit is transmitted from the cable 63 to the sensor heating block 54.
, The sensor heating block 54 is heated. Further, when the thermopile sensor 55 and the printed circuit board 56a advance toward the distal end of the main body case 51 by the slide mechanism 59 described later, the hollow portion of the sensor heating block 54 is formed between the outer peripheral surface of the thermopile sensor 55 and the sensor heating block 54. It is configured to be cut into a truncated cone shape so that the peripheral surfaces contact each other.

On the other hand, the temperature measurement circuit unit 53 includes printed circuit boards 56a and 56b in which the temperature measurement circuit is incorporated, a switch 57 directly attached to the printed circuit board 56b, and a liquid crystal temperature display 58.
And a slide mechanism 59. The printed board 56b is fixed to the main body case 51, and the printed boards 56a and 56b are
As shown in the figure, they are connected by a spring 64 and a cable 65. The switch 57 and the liquid crystal temperature indicator 58 are exposed to the outside of the main body case 51 through holes provided in the main body case 51, respectively. When the switch 57 is pressed, the body temperature measurement starts, and the liquid crystal temperature display 58 digitally displays the measured body temperature.

In addition, the slide mechanism 59 includes electromagnets 66a and 66b provided on opposing surfaces of the printed boards 56a and 56b, respectively.
And a spring 64 connecting the printed boards 56a and 56b. Normally, the thermopile sensor 55 and the printed board 56a are urged toward the printed board 56b 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 direction of the sensor heating block 54 due to the repulsive force due to electromagnetic induction, and as shown in FIG. The sensor 55 and the sensor heating block 54 come into contact with each other. After the temperature measurement, when the power to the electromagnets 66a and 66b is released, the thermopile sensor
55 and the printed board 56a are urged in the direction of the printed board 56b by the elastic force of the spring 64, and return to the original position.

Here, the temperature measurement circuit will be described with reference to the block circuit diagram of FIG.

In FIG. 5, a thermopile sensor 55 provided in the ear thermometer outputs a voltage depending on the amount of infrared rays 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,
This output is output as a positive voltage when the temperature of the measurement target is higher than the temperature of the thermopile sensor 55, and is output as a negative voltage when the temperature of the measurement target is lower than the temperature of the thermopile sensor 55. 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
A comparator (voltage comparator) IC 68 connected to the operational amplifier 67, which amplifies the minute voltage output from the thermopile sensor 55 to a predetermined magnitude, 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 is connected to the thermopile sensor 55 regardless of the magnitude of the output of the thermopile sensor 55 and the sign of the output.
A signal indicating whether or not the output of 55 is 0 is sent to the microcomputer 69.

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 thermistor 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. 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 sends the temperature value output of the measurement target to the liquid crystal temperature display 58. . The liquid crystal temperature display 58 digitally displays the temperature of the measurement target.

The drive IC 71 transmits a heating command signal from the microcomputer 69 to the 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 microcomputer is set 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 from 69 to the sensor heating block 54. Therefore, at the start of temperature measurement, the temperature of the sensor heating block 54 has risen to the set temperature.

An instruction to start temperature measurement is issued from an external microcomputer.
When transmitted to 69, the slide mechanism 59 operates and the thermopile sensor 55 contacts the sensor heating block 54 as described above. Then, the thermopile sensor 55 is rapidly heated by the heat conducted from the previously heated sensor heating block 54, and the output of the thermopile sensor 55 is rapidly reduced. When 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 signal indicating the presence or absence of the output of the thermopile sensor 55 is sent to the microcomputer 69 by the comparator IC 68, the thermopile sensor 55
The microcomputer calculates the temperature of the thermopile sensor 55 when the output of the
The temperature of the eardrum to be measured is detected by the 69 performing the arithmetic processing. The detected temperature of the eardrum is indicated by the LCD temperature indicator 58.
It is recognized by being displayed by.

As described above, the ear thermometer according to the present embodiment includes a thermopile sensor 55 having a truncated cone shape and a case body.
51 Providing at the tip eliminates the need for parts such as a waveguide and a support plate to support the thermopile sensor, and also reduces the distance between the thermopile sensor and the eardrum, so infrared energy is proportional to the square of the distance. As a result,
A large improvement in the sensitivity of the thermopile sensor leads to a large improvement in output, resulting in a high-precision radiation thermometer with a low number of parts and a low number of parts while improving the measurement accuracy.

Also, by providing 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 59. In addition, since the thermopile sensor 55 can be heated by sliding the thermopile sensor 55 on the sensor heating block 54 that has been heated in advance, 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 thermopile sensor 55 having a truncated cone shape with respect to the sensor heating block 54 by a small distance. Therefore, a maximum heating or heat radiation effect can be obtained with a minimum slide amount.

In the ear thermometer according to the present embodiment, the slide mechanism is the slide mechanism 59 using the electromagnets 66a, 66b and the spring 64, but is not limited thereto.
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 only by sliding the frusto-conical thermopile sensor 55 with respect to the sensor heating block 54 by a small distance. Therefore, a maximum heating or heat radiation effect can be obtained with a 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 above-described ear thermometer does not include a heating device, and is a sensor heat radiation block 72. . The heating device is attached to the thermopile sensor 55. For example, as shown in FIG. 6, a heating device 73 is wound on the outer peripheral surface of the thermopile sensor 55.
Further, the cable 63 in the above-mentioned ear thermometer 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,
The thermopile sensor 55 contacts the sensor heat radiation block 72. Then, the heat of the thermopile sensor 55 is conducted to the sensor heat radiating block 72, whereby the heat is rapidly radiated and the output of the thermopile sensor 55 increases rapidly. When 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 zero. After that, 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 has the heating device 73 wound on the outer peripheral surface of the thermopile sensor 55 as described above, but is not limited thereto. Instead, 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. 7 (a) is a perspective view showing a thermo module 74 attached to the ear thermometer according to the present embodiment, and FIG. 7 (b) is a perspective view showing a state where the thermo module 74 is attached to the thermopile sensor 55. FIG. In FIG. 7 (b),
For convenience of explanation, the bottom surface portion of the sensor heat dissipation block 72 having a truncated cone shape is omitted.

As shown in FIG. 7A, the thermo module 74 has a Peltier device 75 and a lead wire 76. The upper surface of the Peltier device 75 is a cooling surface 77 and the lower surface is a heating surface 78. 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, the heating surface 78 of the Peltier element 75 is adhered substantially to the center of the stem 45 of the thermopile sensor 55 as shown in FIG. The tip 80 of the flat plate 79 is adhered to the inner peripheral surface of the sensor heat radiation block 72. The lead wire 76 is connected to the printed board 56a. The flat plate 79 is formed of a metal having good heat conductivity, and has elasticity so as not to hinder the sliding of the thermopile sensor 55.

In the ear thermometer to which the thermo module 74 shown in FIG. 7 is attached, the thermopile sensor 55
At the same time, the cooling surface 77 of the Peltier element 75 absorbs the heat of the sensor radiation block 72 via the flat plate 79, that is, cools the sensor radiation block 72, so that the sensor radiation block 72 is cooled in advance. You can keep. Therefore, when the slide mechanism 59 is operated by the instruction to start temperature measurement and the thermopile sensor 55 comes into contact with the sensor radiation block 72, the thermopile sensor 55 can be efficiently cooled in a short time.

As described above, the ear thermometer according to the present embodiment is a thermopile sensor 55 having a truncated cone shape, a heating device for heating the thermopile sensor 55, and a sensor heat radiation device having a hollow portion adapted to the truncated cone shape. Block 72,
By having the slide mechanism 59, the pre-heated thermopile sensor 55
To cool down, for example,
The cooling (temperature adjustment) of the thermopile sensor can be performed in a shorter time than when the thermopile sensor heated in advance is cooled by natural heat radiation. Therefore, the measurement time can be reduced.

Also, 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 a sensor radiation block.
If it is connected to 72, the thermopile sensor 55 can be heated in advance and the sensor radiation block 72 can be cooled at the same time. Therefore, cooling (temperature adjustment) of the thermopile sensor 55 can be performed in a shorter time. Therefore, the measurement time can be further reduced.

FIG. 8 is an external view showing an embodiment of a radiation thermometer module provided by incorporating a Peltier element 75 used as a thermo module in a package 47. The package has a tapered shape such as a truncated cone or a truncated pyramid that tapers toward the infrared transmission window 46. This is the same as the infrared sensor module using the thermopile shown in FIG.

FIG. 9 shows the internal configuration of the radiation thermometer shown in FIG. In the present embodiment, a thermopile sensor 55 and a thermomodule having a conventional cylindrical package 47 are provided inside a package having a tapered shape such as a truncated conical shape or a truncated pyramid shape tapered toward the infrared transmission window 46. I have. The thermo module has an infrared transmission window 46
Since it is provided inside the package 47 having a tapered shape such as a truncated conical shape or a truncated pyramid shape, it is not necessary to pay attention to the space outside the package.
A Peltier element 75 is used for the thermo module. Whether to select the heat absorption side or the heat generation side for the heat connection surface is determined by the conditions such as the surrounding environment and the reference temperature setting. Since the Peltier element 75 has the characteristic that the heat absorbing surface and the heat generating surface are switched only by inverting the polarity of the power supply,
Even if an operation of switching between cooling and heating occurs during the operation of the radiation thermometer of the present embodiment, it can be realized without major changes in hardware. A comparator and a controller (not shown) provided separately perform the determination and operation for the polarity inversion of the Peltier element 75.

The conventional thermopile sensor 55 has a stem 45 as a constituent element through a terminal. However, in the radiation thermometer module according to the present embodiment, a truncated cone and a pyramid taper toward an infrared transmission window 46. The peripheral edge of the stem 45 of the conventional thermopile sensor 55 extends to the inner surface of the package 47 having a tapered shape such as a trapezoid, and halves the internal space of the module. In the present embodiment, a cooling / heating device using a Peltier element 75 is included in each of the two divided spaces. The Peltier element 75 thermally connected to the terminal is used to efficiently change the temperature of the cold junction of the electrode pins 3 and 4 of the thermopile sensor 55.
The Peltier element 75 provided above the stem 45 is thermally connected to the side surface of the package 47 of the conventional thermopile sensor 55 and plays a role as a preheating device until the start of temperature measurement. The Peltier element 75, which is a thermo module, may be thermally connected to the inner surface of the package 47 having a tapered shape such as a truncated cone or a truncated pyramid toward the infrared transmission window 46 with the stem 45 as a boundary. In this case, although not shown, a module can be provided without the package 47 of the conventional thermopile sensor 55. The package 47 having a tapered shape such as a truncated cone or a truncated pyramid that tapers toward the infrared transmission window 46 is made of a material such as a metal having good thermal conductivity for a portion including the Peltier element 75 for preheating with the stem 45 as a boundary. The portion including the Peltier element 75 thermally connected to the cold junctions of the electrode pins 3 and 4 of the thermopile sensor 55 is made of a resin material having excellent heat insulation.

By providing the radiation thermometer as a module, it is not necessary to design the combination part of the thermopile sensor and the thermomodule, so that the development cost and labor of applied products are reduced and versatility is improved.

Continuation of the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) G01J 5/00-5/62 G01J 1/00-1/60 JICST file (JOIS) WPI / L (QUESTEL) Practical file ( (PATOLIS) Patent file (PATOLIS) EUROPAT (QUESTEL)

Claims (7)

(57) [Claims] 1. An infrared sensor comprising: an infrared detection element; a stem having an electrode connected to the infrared detection element inserted therethrough; and a package attached to the stem and provided with an infrared receiving window for enclosing the infrared detection element. A radiation thermometer provided with a sensor 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. Total. 2. An infrared sensor comprising: an infrared detecting element; a stem having an electrode connected to the infrared detecting element inserted therethrough; and a package attached to the stem and having an infrared receiving window for enclosing the infrared detecting element. A radiation thermometer provided with a heating device for heating the infrared sensor, a sensor heat radiation block having a hollow portion, and a slide mechanism for sliding the infrared sensor with respect to the sensor heat radiation block. Radiation thermometer. 3. 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, is provided on the infrared receiving window side of the package. A sensor heating block having a hollow portion that fits a tapered portion of the infrared sensor in a radiation thermometer having an infrared sensor having a tapered portion whose diameter is smaller than the diameter of the stem side; and the sensor heating block. A heating device for heating the sensor and a slide mechanism for sliding the infrared sensor with respect to the sensor heating block. 4. 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 light receiving window attached to the stem and enclosing the infrared detection element. The package has an infrared sensor in the form of a cone or a truncated pyramid whose diameter on the infrared receiving window side of the package is smaller than the diameter on the stem side. A sensor heating block having a portion, a heating device for heating the sensor heating block,
A radiation mechanism provided with a slide mechanism for sliding the infrared sensor with respect to the sensor heating block. 5. 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, is provided on the infrared receiving window side of the package. A heating device for heating the infrared sensor to a radiation thermometer having an infrared sensor having a tapered portion whose diameter is smaller than the diameter of the stem side, and a sensor having a hollow portion adapted to the tapered portion of the infrared sensor A radiation thermometer comprising: a heat radiation block; and a slide mechanism for sliding the infrared sensor with respect to the sensor heat radiation block. 6. An infrared sensor comprising: an infrared detection element; a stem through which an electrode connected to the infrared detection element is inserted; and a package attached to the stem and provided with an infrared light receiving window for enclosing the infrared detection element. A heating device for heating the infrared sensor, wherein the package has a radiation thermometer having an infrared sensor in the shape of a cone or truncated pyramid in which the diameter of the package on the infrared receiving window side is smaller than the diameter of the stem side; A radiation thermometer comprising: a sensor heat-dissipating block having a hollow portion adapted to a truncated cone of an infrared sensor; and a slide mechanism for sliding the infrared sensor with respect to the sensor heat-dissipating block. 7. The thermo-module using a Peltier element having a heating surface and a cooling surface, wherein the heating device is connected to the infrared sensor, and the cooling surface is connected to the sensor radiating block. The radiation thermometer according to claim 2 or claim 5 or claim 6.