JPS60203828A - Remote measuring thermometer - Google Patents

Abstract

PURPOSE:To omit a cable or the like by detecting a resonance frequency from a response signal of a sensor for receiving a carrier including a sweeping signal having the resonance frequency to be changed by the temperature of a ceramic resonator and measuring the temperature of the ceramic resonator. CONSTITUTION:A sensor part 2 is constituted of the ceramic resonator 1 changing its resonance frequency f1 in accordance with temperature, a diode 5, an electromagnetic coupler 6, and an antenna 4 to output a carrier S0 of a microwave band having frequency f0 modulated by a sweeping signal S1 of an intermediate wave band, and a measuring device part 3 is constituted of a transmission/reception part 14 for analyzing a response signal S5 from the sensor part 2 and an antenna 15. The carrier S0 including the signal S1 from the antenna 15 is received by the antenna 4 and applied to the resonator 1 to generate a riging signal corresponding to the frequency f1 and the frequency f0, f1 components are radiated from the antenna 4 and received by the antenna 15 to detect the frequency f1 and detect the temperature of the resonator 1, e.g. an internal temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a remote measuring thermometer that measures the temperature inside a human body, the temperature in an isolated part such as a nuclear reactor, and the like.

[Technical Background of the Invention] The technical background of the present invention will be explained in the case of heat-sensitive therapy (hyperthermia) for the human body.

In the treatment of cancer, heat-sensitive therapy is known that kills cancer cells while keeping the cancer (tumor) area at about 42°C.

The heat source in this heat-sensitive therapy uses microwaves, ultrasound, etc.

The problem in this case is to know the temperature of the affected area accurately;
In the past, thermal lightning pairs were implanted inside the body to detect temperature.

However, with such means, it is necessary to connect the thermocouple to a measuring instrument, so that the thermocouple must be implanted in the human body each time the body is heated.

This situation also applies to thermometers using optical fibers.

This thermometer using an optical fiber coats the tip of the optical fiber with a phosphor that changes its fluorescence emission spectrum as the temperature changes, and stimulates light from outside the body by passing this optical fiber into the body. Body temperature is detected by analyzing changes in the fluorescence emission spectrum.

[Problems in the Background Art] In the conventional temperature measuring means described above, the measuring instrument and the temperature sensor part are connected by a cable, optical fiber, etc. There was also a problem in that there were restrictions on the placement of the stupid measuring device that needed to be embedded.

This situation applies not only to thermotherapy but also to remote measurement of the temperature of nuclear reactors and the like.

[Objective of the Invention] The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a remote measuring thermometer that does not require any connection using cables, optical fibers, etc. and is capable of measuring the temperature of a desired location from the outside as necessary. This is the purpose.

[Summary of the Invention] To achieve the above object, the present invention has a ceramic resonator whose resonant frequency changes with temperature changes, receives a carrier wave containing a sweep signal of the resonant frequency from the outside, and generates the resonant wave. a sensor section that sends out a response signal including a ringing signal corresponding to the frequency; a measurement section that sends the carrier wave to the sensor section and receives the response signal from the sensor section to detect the resonant frequency of the ceramic resonator; The present invention is characterized in that the temperature of the ceramic resonator is measured from the detection result of the measuring section.

[Embodiments of the Invention] Below, a case where the measurement principle and embodiments of the present invention are applied to the measurement of body temperature in the case of thermosensitive therapy will be described.

The temperature measurement principle of the present invention is to transmit a carrier wave of a predetermined frequency from the outside to a ceramic resonator whose resonant frequency changes depending on the temperature that is embedded in the body, and to transmit a response signal of a specific frequency determined by the resonant frequency of the ceramic resonator to the outside. By transmitting and identifying this specific frequency, the temperature of the ceramic resonator, that is, the temperature inside the body is measured.

That is, the resonance frequency of the ceramic resonator 1 shown in FIG. 1 is set to [i, and the sweep signal S1 is applied to the ceramic resonator 1 as shown in FIG. 2(a).

The ceramic resonator 1 receiving this sweep signal S1 starts to resonate, and as shown in FIG. 2(b), the resonant frequency f1 is
generates a ringing signal S2 corresponding to .

Based on this ringing signal S2, a ringing response signal S corresponding to the resonance frequency f1 as shown in FIG.
s, a ringing response signal S as shown in Fig. 2(d)
If the resonant frequency 11 of the Semiconductor resonator 1 is detected by applying the pulse signal S4 corresponding to
Since the relationship between and temperature is known in advance, that temperature, that is, the temperature inside the body, can be measured.

Next, a first embodiment for realizing the above-mentioned measurement principle will be described with reference to FIG.

The telemetry thermometer shown in the figure includes a sensor section 2 and a measuring device section 3.

The sensor section 2 has a C configuration including an antenna 4, a diode 5, an electromagnetic coupler 6, and the ceramic resonator 1 whose resonance frequency f1 changes depending on temperature.

A specific example of the configuration of the ceramic resonator 1 will be explained with reference to FIG.

In the figure, 11 is, for example, Pb Ti Os -Pb
It is a ceramic piezoelectric element formed by Zr 03-Pb (Cow > t /20s, etc.) and whose polarization axis is set in the long direction.Usually, a ceramic piezoelectric element that has been refined in consideration of temperature characteristics is used, but in this example By adding a small amount of additives such as silicon (St), the temperature characteristics correspond to the temperature inside the body.

12a and 12B are electrodes provided on both sides of this ceramic voltage element 11, and 13a is a terminal for connecting this electrode 12a to the outside. Electrode 12b also has a similar terminal.

This ceramic resonator 1 can be constructed extremely simply and compactly, and moreover, can be constructed as a so-called passive element that does not require a power source. Therefore, the sensor section 2 as a whole can also be configured as an all-solid-state element with excellent reliability and shock resistance.

The measuring device section 3 is configured to operate in a medium wave band (for example, 1.0~2°5MH).
2) A transmitting/receiving unit 14 that outputs a microwave band carrier wave So (frequency fO; for example, 2.45 GHz) modulated by the sweep signal S1 of 2) and analyzes a response signal Ss (described later) from the sensor unit 2, and a carrier wave. So, and an antenna 15 for transmitting and receiving a response signal S5.

Next, the operation of the telemetry thermometer having the above configuration will be explained in the case where the sensor section 2 is implanted in the body.

The microwave band carrier wave So transmitted from the antenna 15 of the measuring instrument section 3 is received by the antenna 4 of the sensor section 2 inside the body.

The sweep signal S1 included in this carrier wave So is transmitted to the diode 5.
This sweep signal S1 is applied to the ceramic resonator 1 via the electromagnetic coupler 6.

Based on this sweep signal S1, the ceramic resonance frequency f1
A ringing signal S2 corresponding to this is generated.

This ringing signal S2 is continuously modulated again by the carrier wave So sent to the center section 2, and as a result, a response signal S including the frequency fo acid component resonance frequency f1 configuration is obtained.
5 is radiated to the outside from the antenna 4.

This response signal S5 is received by the antenna 15 of the measuring instrument section 3, and synchronously detected together with the sweep signal S1 in the transmitter/receiver section 14, resulting in a ringing response signal S3 shown in FIG. 2(0).
is converted to By detecting the frequency of this ringing response signal S3, the resonance frequency 11 can be measured, and therefore the temperature of the ceramic resonator 1 corresponding to this, that is, the temperature inside the body can be known.

Further, the ringing response signal S3 is converted into a pulse signal S4 as shown in FIG. 2(d') by, for example, a matched filter.
It is also possible to determine the temperature relative to the ceramic vibration by converting the pulse signal S4 to the sweep signal S1 and determining the position of the pulse signal S4 on the time axis with respect to the sweep signal S1.

Note that the frequency of the carrier wave So mentioned above is not particularly limited, but may be in the so-called 18M band (915MHz, 2
．． 45 GHz, etc.) is advantageous due to radio law regulations.

Next, a second embodiment for realizing the measurement principle described above will be described with reference to FIG.

The telemetry thermometer shown in the figure includes a sensor section 2A consisting of an antenna coil 21, a high-frequency coupling capacitor 22, and a ceramic resonator 1, and a measuring instrument section 3A consisting of a transmitting/receiving section 14A and an antenna coil 23. has been done.

A sweep signal Ss in a frequency range of 269 to 532 KH2 is transmitted from the transmitting/receiving section 14A via the antenna coil 23.
' will be sent directly. This sweep signal Ss' is received by the antenna coil 21 and applied to the ceramic resonator 1 via the high frequency coupling capacitor 22. As a result, a resonance phenomenon with a resonance frequency f1 occurs in the ceramic resonator 1, and a ringing signal 82' corresponding to this resonance frequency f1 is sent from the antenna coil 21 to the antenna coil 23.

The transmitting/receiving section 14A analyzes the frequency of this ringing signal 32' and measures the resonant frequency f1 of the ceramic resonator 1.

The detected resonance frequency f1 causes the ceramic resonator 1 to
temperature, that is, the temperature inside the body.

In addition to detecting the internal temperature by measuring the resonant frequency 11 as described above, it is also possible to detect that the ringing signal 82' is generated from the moment the frequency of the sweep signal 81' matches the resonant frequency 11 of the ceramic resonator 1. The internal temperature of the body can also be determined by detecting the position of the ringing signal S2' on the time axis relative to the sweep signal 81'.

The above-mentioned remote measuring thermometer has various uses in addition to measuring the temperature of the human body.

For example, the temperature of a required part can be measured by attaching a sensor section to a trolley set of electron tube exhaust/aging device.

In this case, if the resonant frequency of each ceramic resonator built in the sensor section installed in each electron tube exhaust/aging device is set to be slightly different,
Even if the frequency of the sweep signal from the measuring instrument is the same, its response i
Since the frequencies of the = signs are different, it becomes possible to identify each electron tube exhaust/aging device.

It is also possible to measure the temperature of parts of nuclear reactors, radiation therapy rooms, etc. that are inaccessible to workers, and to measure the temperature of objects while running on large ceilings, such as TV sets during heat runs.

Ru.

For example, in the above-described embodiment, the case where the sensor unit has one ceramic resonator has been described, but by using a plurality of ceramic resonators, it is also possible to obtain a plurality of temperatures in one measurement.

[Effects of the Invention] According to the present invention described in detail above, there is no need to connect the sensor section and the measuring instrument section with cables, optical fibers, etc., and there is no need for a driving power source for the sensor section 9, and the sensor section can be connected to the inside of the human body. It is possible to provide a telemetry thermometer that can remotely measure the temperature of a desired location, such as a location that cannot be accessed by one worker.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of a ceramic resonator, Figure 2 (a) is a waveform diagram of a sweep signal showing the measurement principle of the present invention, and Figure 2 (b) is a waveform diagram of a sweep signal showing the measurement principle of the present invention.
) is a waveform diagram of the ringing signal as above, FIG. 2(C) is a waveform diagram of the ringing response signal as above, FIG. 2(d) is a waveform diagram of the pulse signal as above, and FIG. FIG. 4 is a perspective view showing a specific configuration example of a ceramic resonator, and FIG. 5 is a circuit diagram showing a second embodiment of the present invention. 1...Ceramic resonator, 2.2A...Sensor section, 3,3A...
・Measuring instrument section, Sl...Sweep signal, S2...Ringing signal, S3...Ringing response signal, S4...
・Pulse signal. ) Snout 2nd figure (b) f+ (C) S4-1''■-1

Claims (3)

[Claims] (1) A sensor unit that has a ceramic resonator whose resonant frequency changes with temperature changes, receives a carrier wave containing a sweep signal of the resonant frequency from the outside, and sends out a response signal that includes a ringing signal corresponding to the resonant frequency. and a measurement section that transmits the carrier wave to the sensor section and receives a response signal from the sensor section to detect the resonant frequency of the ceramic resonator, and measures the temperature of the ceramic resonator from the detection result of the measurement section. A remote sensing thermometer characterized by: (2) The measurement unit is configured to measure the temperature of the ceramic resonator from the positional relationship on the time axis between the ringing signal in the received response signal and the sweep signal. A remote sensing thermometer according to scope 1. (3) The telemetry thermometer according to claim 1, wherein the frequency of the sweep signal is a medium wave band, and the carrier wave is a microwave.