JP5248973B2 - Temperature measuring device - Google Patents

Description

  The present invention relates to a temperature measurement device that measures the temperature of an object to be measured using a non-powered temperature sensor and calibrates the temperature calculation calibration device according to the non-powered temperature sensor.

  In recent years, a non-powered temperature sensor that can wirelessly transmit the temperature of an object to be measured without supplying electric power has attracted attention. In general, a SAW sensor is used as the non-powered temperature sensor (see Patent Document 1).

  In Patent Document 1, a burst wave is transmitted from a base station to be remotely measured, the burst wave is received by an antenna provided in the SAW sensor, a surface acoustic wave is excited by a comb electrode in the SAW sensor, and passes through another comb electrode. Radiated as electromagnetic waves from the antenna. In the SAW sensor, since the propagation speed of the surface acoustic wave varies depending on the temperature, the object to be measured is based on the phase difference (time difference) between the burst wave transmitted from the base station and the electromagnetic wave received by the base station. Temperature can be measured.

JP 2004-150860 A

  However, if the SAW sensor is used for a long time, the phase difference of the electromagnetic wave is different even at the same temperature due to a change with time, and the temperature of the object to be measured may not be measured accurately.

  The present invention has been made in consideration of the above-described problem, and is a temperature measuring device that can prevent the occurrence of a measurement error in the temperature of an object to be measured even when the non-powered temperature sensor changes with time. The purpose is to provide.

Temperature measurement apparatus according to the present invention, and the parasitic temperature sensor for outputting a signal corresponding to the temperature of the object to be measured, by calibrating their temperature based on the output signal from the passive temperature sensors, the object and a temperature calculation calibration device asking you to calibration data for correcting the temperature of the measured object, the passive temperature sensor, a wireless output signal corresponding to the temperature of the object to be measured to the temperature calculating calibration device The temperature calculation calibration device calculates the temperature of the measurement object based on the output signal corresponding to the temperature of the measurement object and the calibration data , and the electric field of the output signal corresponding to the temperature of the measurement object When the intensity is greater than or equal to a threshold, it is determined that the non-feed temperature sensor is placed on the temperature calculation calibration device, and the temperature of the temperature calculation calibration device is calibrated based on the output signal of the non-feed temperature sensor , Proofreading And wherein the Rukoto asked for over data.

  In the temperature measurement device, the temperature calculation calibration device determines that the non-powered temperature sensor is placed on the temperature calculation calibration device when the electric field strength of the output signal corresponding to the temperature of the object to be measured is greater than or equal to a threshold value. By calibrating according to the non-powered temperature sensor, it is possible to prevent the temperature measurement error from occurring due to the time-dependent change of the non-powered temperature sensor. Further, a person who measures the temperature of the object to be measured by the non-powered temperature sensor can calibrate the temperature calculation calibration device corresponding to the non-powered temperature sensor without being conscious of it.

  In addition, the calibration of the temperature calculation calibration device is performed by measuring the temperature of the temperature calculation calibration device measured by a temperature sensor provided in the temperature calculation calibration device and the temperature calculated by the non-powered temperature sensor placed on the temperature calculation calibration device. You may perform based on the temperature of a calculation calibration apparatus.

  Further, the temperature calculation / calibration apparatus may record the calculated temperature of the object to be measured, and display a temperature change of the object to be measured on a display unit based on the recorded temperature of the object to be measured.

  Furthermore, the non-powered temperature sensor is preferably a surface acoustic wave element.

  According to the present invention, the temperature measuring device determines that the non-powered temperature sensor is placed on the temperature calculation calibration device when the electric field strength of the output signal corresponding to the temperature of the object to be measured is greater than or equal to the threshold value. By calibrating the temperature calculation / calibration device based on the output signal from the power supply temperature sensor, it is possible to prevent the temperature measurement error from occurring due to the time-dependent change of the non-power supply temperature sensor. Further, a person who measures the temperature of the object to be measured by the non-powered temperature sensor can calibrate the temperature calculation calibration device corresponding to the non-powered temperature sensor without being conscious of it.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is an explanatory diagram of the entire temperature measuring device 10 according to the embodiment of the present invention, FIG. 1B is an explanatory diagram of calibration of a temperature calculation calibration device 40 based on the non-powered temperature sensor 20, and FIG. FIG. 3 is an explanatory diagram of the configuration of the non-powered temperature sensor 20 and the configuration of the temperature calculation / calibration device 40, and FIG. 3 is a diagram illustrating the relationship between the phase difference used to calculate the temperature of the patient 32 and the temperature.

  The temperature measuring device 10 includes a non-powered temperature sensor 20 and a temperature calculation calibration device 40, and wireless communication is performed between the non-powered temperature sensor 20 and the temperature calculation calibration device 40. The parasitic power temperature sensor 20 includes an antenna 22 for receiving a burst wave radiated from the temperature calculation calibration device 40 and a surface acoustic wave element 24.

The surface acoustic wave element 24 includes a comb electrode 26 and a reflector 28, which are formed on the piezoelectric substrate 30. The comb electrode 26 is an electrode for exciting the surface acoustic wave based on the burst wave received by the antenna 22. The reflector 28 includes a plurality of convex portions formed by vapor-depositing a metal film on the piezoelectric substrate 30 so as to extend in a direction perpendicular to the propagation direction of the surface acoustic wave output from the comb electrode 26. The The piezoelectric substrate 30 is not particularly limited as long as it can propagate a surface acoustic wave, but is preferably a 36 ° Y-plate X propagation LiTaO ₃ .

  The temperature calculation calibration device 40 includes an antenna 42, a transmission unit 44 that transmits a burst wave to the parasitic temperature sensor 20, a reception unit 46 that receives a signal from the parasitic power sensor 20, and a transmission unit 44. A transmitter / receiver 48 for sharing the antenna 42 at the time of transmission and reception at the reception unit 46, and a phase difference (time difference) between the transmission signal transmitted from the transmission unit 44 and the reception signal received by the reception unit 46 The phase difference detector 50 for detecting φ, the electric field intensity detector 52 for detecting the electric field intensity E of the received signal, and the temperature detected by the patient (measurement object) 32 and the level detected by the phase difference detector 50. A controller 54 that corrects the phase difference, a memory 56 that records the temperature of the patient 32, a display 58 that displays the temperature (body temperature) of the patient 32, and a temperature used for temperature calibration of the temperature calculation calibration device 40. Sensor 60

  The antenna 42 is preferably provided in the center of the upper surface of the casing of the temperature calculation calibration device 40 in consideration of the electric field strength, and is not provided in the calibration region 62 centered on the position where the antenna 42 is provided. A power supply temperature sensor 20 is placed.

  The transmitter / receiver 48 is configured to be switched by a switch at the time of signal transmission and reception in order to prevent the transmission signal from the transmission unit 44 from entering the reception unit 46.

  The control unit 54 calculates the temperature of the patient 32 based on the phase difference between the transmission signal from the transmission unit 44 detected by the phase difference detection unit 50 and the reception signal from the reception unit 46. The temperature of the patient 32 is calculated using the relationship between the phase difference and temperature prepared in advance in the control unit 54. For example, the temperature of the patient 32 can be obtained based on the detected phase difference φ using a diagram showing the relationship between the phase difference and temperature as shown in FIG. Further, the control unit 54 compares the electric field strength E of the reception signal output from the electric field strength detection unit 52 with a preset threshold value Eth of the electric field strength. When the electric field intensity E is larger than the threshold value Eth, it is determined that the non-feed temperature sensor 20 is placed on the temperature calculation calibration device 40 and the temperature calculation calibration device 40 is based on the output signal from the non-feed temperature sensor 20. Start temperature calibration. When the electric field strength E is smaller than the threshold value Eth, the temperature of the patient 32 is calculated by the control unit 54.

  Note that the threshold Eth is transmitted after a burst wave is transmitted from the transmission unit 44 and received by the non-powered temperature sensor 20 when the non-powered temperature sensor 20 is placed in the calibration region 62 of the temperature calculation calibration device 40. The value is set to be slightly smaller than the electric field strength of the signal transmitted from the non-powered temperature sensor 20 to the temperature calculation calibration device 40. Further, the temperature of the patient 32 calculated by the non-powered temperature sensor 20 can be recorded in the memory 56, and the recorded temperature of the patient 32 is displayed on the display 58 or the result of statistical processing is displayed on the display. 58 can also be displayed.

  Measurement of the temperature of the patient 32 using the temperature measurement device 10 and calibration of the temperature calculation calibration device 40 based on the output signal from the non-powered temperature sensor 20 are performed as follows.

  First, the temperature of the temperature calculation calibration device 40 is calibrated based on the output signal of the non-powered temperature sensor 20. For this calibration, the non-powered temperature sensor 20 is placed in the calibration area 62 of the temperature calculation calibration device 40 (see FIG. 1B). Next, a burst wave is generated in the transmission unit 44 and transmitted from the antenna 42 via the transducer 48, and at the same time, the burst wave is transmitted from the transmission unit 44 to the phase difference detection unit 50.

  The transmitted burst wave is received by the antenna 22 of the parasitic temperature sensor 20. The received burst wave is excited by the comb electrode 26, propagates as a surface acoustic wave on the piezoelectric substrate 30, is reflected by the reflector 28, and reaches the comb electrode 26. The surface acoustic wave that has reached the comb electrode 26 is converted into a radio wave by the antenna 22 and transmitted to the temperature calculation calibration device 40 as a detection signal. The detection signal is a signal corresponding to the temperature detected by the non-powered temperature sensor 20 and calculated by the temperature calculation calibration device 40.

  The detection signal is received by the receiving unit 46 via the antenna 42 and the transducer 48 of the temperature calculation calibration device 40, and output to the phase difference detection unit 50 and the electric field strength detection unit 52. In the phase difference detection unit 50, the phase difference φ 0 between the burst wave transmitted from the transmission unit 44 and the detection signal is detected and output to the control unit 54. In the electric field strength detection unit 52, the electric field strength E of the detection signal output from the reception unit 46 is detected and output to the control unit 54.

  In the control unit 54, the electric field strength E is compared with the threshold value Eth, and when the non-powered temperature sensor 20 is mounted on the temperature calculation calibration device 40, the electric field strength E is larger than the threshold value Eth, so that the temperature calculation is performed. The temperature of the calibration device 40 is calibrated. In the temperature calibration of the temperature calculation calibration device 40, the temperature t0 of the temperature calculation calibration device 40 itself measured by the temperature sensor 60 is output to the control unit 54, and this temperature t0 is calculated from the relationship between the phase difference and the temperature as shown in FIG. Is read out. A difference Δφ (= φ0−φt0) between the phase difference φt0 and the phase difference φ0 of the detection signal is stored in the control unit 54 as calibration data. In the subsequent measurement of the temperature of the patient 32 by the non-powered temperature sensor 20, the control unit 54 determines the temperature of the patient 32 based on the phase difference obtained by correcting the phase difference φ of the detection signal from the non-powered temperature sensor 20 with the calibration data Δφ. Calculated.

  After calibration of the temperature calculation calibration device 40, the non-powered temperature sensor 20 is installed in the patient 32 (see FIG. 1B), and measurement of the temperature of the patient 32 is started. In the measurement of the temperature of the patient 32, a burst wave is transmitted from the transmitter 44 and received by the non-powered temperature sensor 20 and then excited by the comb electrode 26, as in the temperature calibration of the temperature calculation calibration device 40 described above. It propagates as a surface acoustic wave on the piezoelectric substrate 30, is reflected by the reflector 28, and reaches the comb-shaped electrode 26. The surface acoustic wave that has reached the comb electrode 26 is converted into a radio wave by the antenna 22 and transmitted to the temperature calculation calibration device 40 as a detection signal.

  The detection signal is received by the reception unit 46 via the antenna 42 and the transducer 48 and output to the phase difference detection unit 50 and the electric field strength detection unit 52. In the phase difference detection unit 50, the phase difference φ between the burst wave transmitted from the transmission unit 44 and the detection signal is detected and output to the control unit 54. In the electric field strength detection unit 52, the electric field strength E of the detection signal output from the reception unit 46 is detected and output to the control unit 54.

  In the control unit 54, the electric field strength E is compared with the threshold value Eth, and when the non-powered temperature sensor 20 is attached to the patient 32, the electric field strength E is smaller than the threshold value Eth. Temperature is required. The temperature of the patient 32 is obtained from the phase difference obtained by correcting the phase difference φ with the calibration data Δφ and the relationship between the phase difference and the temperature as shown in FIG.

  The obtained temperature is recorded in the memory 56 and also output to the display 58, and the temperature of the patient 32 is displayed.

  When the non-powered temperature sensor 20 is used, the characteristics of the detection signal may change due to changes over time, and an error may occur in the measurement temperature. In order to prevent the measurement error from occurring, the temperature calibration of the temperature calculation calibration device 40 is performed. Necessary.

  The temperature calibration of the temperature calculation calibration device 40 is performed by placing the non-powered temperature sensor 20 in the calibration region 62 of the temperature calculation calibration device 40 in the same manner as the temperature calibration before the measurement of the temperature of the patient 32 described above. By this calibration, the calibration data before the measurement of the temperature of the patient 32 is updated to become calibration data Δφ ′. In the subsequent measurement of the temperature of the patient 32 by the parasitic power temperature sensor 20, the phase difference as shown in FIG. 3 is based on the phase difference obtained by correcting the phase difference φ of the detection signal from the parasitic temperature sensor 20 with the calibration data Δφ ′. The temperature of the patient 32 is obtained by the control unit 54 from the relationship between the temperature and the temperature.

  As described above, the temperature measuring apparatus 10 according to the embodiment of the present invention is calibrated based on the parasitic power sensor 20 that outputs a signal corresponding to the temperature of the patient 32 and the output signal from the parasitic power sensor 20. The temperature calculation calibration device 40 includes a non-powered temperature sensor 20 that wirelessly transmits an output signal corresponding to the temperature of the patient 32 to the temperature calculation calibration device 40. The temperature of the patient 32 is calculated based on the output signal corresponding to the temperature, and when the electric field strength of the output signal corresponding to the temperature of the patient 32 is equal to or greater than the threshold value, the non-powered temperature sensor 20 is placed on the temperature calculation calibration device 40. It is determined that it has been performed, and calibration is performed based on the output signal of the non-powered temperature sensor 20.

  In this way, the temperature calculation calibration device 40 is calibrated, so that it is possible to prevent the temperature measurement error from occurring due to the time-dependent change of the non-powered temperature sensor 20. Further, a person who measures the temperature of the patient 32 by the non-powered temperature sensor 20 can calibrate the temperature calculation calibration device 40 corresponding to the non-powered temperature sensor 20 without being conscious of it.

  Further, the calibration of the temperature calculation calibration device 40 is performed by measuring the temperature of the temperature calculation calibration device 40 measured by the temperature sensor 60 provided in the temperature calculation calibration device 40 and the temperature calculated by the non-feed temperature sensor 20 mounted. This is performed based on the temperature of the calculation calibration device 40.

  Further, the temperature measuring device 10 records the calculated temperature of the patient 32 in the memory 56 in the temperature calculation / calibration device 40, and the temperature change of the patient 32 is displayed on the display device 58 based on the recorded temperature of the patient 32. By displaying, physical condition management can also be performed efficiently.

  Furthermore, by transmitting burst waves having different frequencies from the transmitter 44, a plurality of non-powered temperature sensors 20 can be installed in the patient 32, and the temperature of the patient 32 can be measured in a multifaceted manner.

  Further, when the electric field intensity of the detection signal detected by the electric field intensity detection unit 52 exceeds the threshold Eth, the fact that the calibration is being performed is displayed on the display 58 of the temperature calculation calibration device 40, an LED or the like May be lit. Further, in addition to the threshold value Eth, a threshold value Ex larger than the threshold value Eth is set in the control unit 54 and compared with the electric field strength of the detection signal. When the electric field strength of the detection signal is larger than the threshold value Ex, If the electric field strength of the detection signal does not exceed the threshold Eth even though the temperature sensor 20 is mounted on the temperature calculation calibration device 40, the fact that the parasitic power temperature sensor 20 has failed is displayed in characters. Alternatively, it may be determined that the non-powered temperature sensor 20 is out of order by not displaying characters or turning on LEDs or the like.

  Further, in FIG. 1A, the patient is the target as the patient 32, but the present invention is not limited to this, and all of those that can measure the temperature are the target. In FIG. 1B, the non-feed temperature sensor 20 is provided in the wristband. However, the object to which the non-feed temperature sensor 20 is provided is not limited to this, and may be appropriately changed according to the patient 32. Can do.

  In addition, the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted without departing from the gist of the present invention.

FIG. 1A is an explanatory diagram of the entire temperature measurement calibration device according to the embodiment of the present invention, and FIG. 1B is an explanatory diagram of calibration of the temperature calculation calibration device by a non-powered temperature sensor. It is explanatory drawing of the structure of a non-power-supply temperature sensor and the structure of a temperature calculation calibration apparatus. It is a figure which shows the relationship between the phase difference used in order to calculate the temperature of a to-be-measured object, and temperature.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Temperature measuring device 20 ... Non-feed temperature sensor 22, 42 ... Antenna 24 ... Surface acoustic wave element 26 ... Comb-shaped electrode 28 ... Reflector 30 ... Piezoelectric substrate 32 ... Patient 40 ... Temperature calculation calibration device 44 ... Transmission part 46 ... Reception Unit 48 ... transducer 50 ... phase difference detection unit 52 ... electric field intensity detection unit 54 ... control unit 56 ... memory 58 ... display 60 ... temperature sensor 62 ... calibration area

Claims (4)

A non-powered temperature sensor that outputs a signal corresponding to the temperature of the object to be measured;
Wherein by calibrating their temperature based on the output signal from the parasitic temperature sensor, and temperature calculation calibration device asking you to calibration data for correcting the temperature of the object to be measured,
With
The non-powered temperature sensor wirelessly transmits an output signal corresponding to the temperature of the object to be measured to the temperature calculation calibration device,
The temperature calculation calibration device calculates the temperature of the measurement object based on the output signal corresponding to the temperature of the measurement object and the calibration data , and the electric field strength of the output signal corresponding to the temperature of the measurement object is a threshold value. In the above case, it is determined that the non-feed temperature sensor is placed on the temperature calculation calibration device, the temperature of the temperature calculation calibration device is calibrated based on the output signal of the non-feed temperature sensor, and the calibration data is temperature measurement apparatus characterized by Ru determined. The temperature measuring device according to claim 1,
The calibration of the temperature calculation calibration device is calculated by the temperature of the temperature calculation calibration device measured by the temperature sensor provided in the temperature calculation calibration device and the non-powered temperature sensor mounted on the temperature calculation calibration device. The temperature measurement device is performed based on the temperature of the temperature calculation calibration device. The temperature measuring device according to claim 1 or 2,
The temperature calculation calibration device records the calculated temperature of the measurement object, and displays a temperature change of the measurement object on a display unit based on the recorded temperature of the measurement object. apparatus. In the temperature measuring device according to any one of claims 1 to 3,
The non-power-feeding temperature sensor is composed of a surface acoustic wave element.

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