JPH08128996A - Ultrasound imaging equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] Each amplifier, switching device, and controller connected to a piezoelectric element for transmitting and receiving ultrasonic waves are formed of vacuum microelements that are heat and radiation resistant, and are installed close to the piezoelectric elements to provide detection sensitivity An ultrasonic imaging device using an ultrasonic sensor unit having excellent resolution is provided. According to a first aspect of the present invention, there is provided an ultrasonic imaging apparatus in which an ultrasonic sensor unit 1 comprising a large number of piezoelectric elements 4 for emitting and receiving ultrasonic waves arranged regularly on a straight line or on the same plane is the piezoelectric element. The element 4, the amplifiers 21 and 23 for transmitting and receiving signals transmitted and received by each piezoelectric element 4, and the amplifier 2 for transmitting and receiving
Transmitter / receiver switch 2 that switches the signal to 1, 23
0, 22 and a controller 19 for controlling them, and the transmission and reception amplifiers 21, 23, the transmission and reception switchers 20, 22 and the controller 19 are all heat- and radiation-resistant. It is characterized in that it is provided in the vicinity of 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is directed to scanning an ultrasonic transducer in an opaque sodium in a liquid metal such as sodium contained as a coolant in a reactor vessel of a liquid metal cooled nuclear reactor such as a fast breeder reactor. Then, the present invention relates to an ultrasonic imaging apparatus for visualizing and inspecting a structure installed in a furnace.

[0002]

2. Description of the Related Art In a conventional ultrasonic imaging apparatus, FIG.
As shown in the block diagram of FIG. 1, the ultrasonic sensor unit 1 that is the in-furnace detection unit is attached to, for example, the tip of the inspection robot arm 2 and is immersed in the opaque liquid metal 3, for example, sodium. On the piezoelectric elements 4 which are regularly arrayed in a plane on the surface of the ultrasonic sensor unit 1, the oscillator 6 is operated based on a command from the signal processing device 5 installed outside the inspection robot arm 2. A voltage pulse signal is emitted.

Further, one of the transmission switching devices 9 is closed according to the switching control command 8 from the controller 7, and the voltage pulse signal from the transmitter 6 is amplified by the transmission amplifier 10 of the closed circuit, 1 as high voltage pulse
It is applied to two piezoelectric elements 4. As a result, the ultrasonic echo 11 is transmitted from the surface of the piezoelectric element 4 into the liquid metal 3. The transmitted ultrasonic echo 11 propagates in the liquid metal 3, is reflected by the object 12, and is received by another piezoelectric element 4.

The minute signal received by the piezoelectric element 4 is input to the receiving amplifier 14 via the circuit of the receiving switching device 13 closed according to the switching control command 8 from the controller 7, and after being amplified, analog, Digital converter 15
(Hereinafter abbreviated as A / D converter).

For example, when the number of the piezoelectric elements 4 is N, the controller 7 sequentially switches one piezoelectric element 4 for transmission for the above operation, and at the same time, the remaining N-1
The individual piezoelectric elements 4 are selected for reception. The received signal from the N-1 piezoelectric elements 4 is taken into the A / D converter 15 and converted into a digital signal to be processed by the signal processing device 5.
Output to. In the signal processing device 5, this signal is subjected to aperture synthesis to form an image, which is an object in an opaque liquid metal.
Twelve images are reproduced so that they can be viewed on the display device 16.

[0006]

In the conventional ultrasonic imaging apparatus, the switching device 13 for reception, which is connected to a large number of piezoelectric elements 4 in the ultrasonic sensor unit 1, the transmission amplifier 10, and the reception amplifier 14, Further, the transmission switching device 9 and the controller 7 are installed outside the inspection robot arm 2. Therefore, it is necessary to accommodate the same number of cables 17 as the many piezoelectric elements 4 inside the inspection robot arm 2, and the number of the piezoelectric elements 4 is increased due to the restriction on the accommodation space, and the ultrasonic sensor unit 1 is provided. There is a problem that the resolution cannot be improved.

Further, since the transmitting amplifier 10 and the receiving amplifier 14 are installed outside the inspection robot, a cable 17 having a long high voltage pulse applied to the piezoelectric element 4 attached to the tip of the inspection robot arm 2 is provided. While being attenuated inside, the weak ultrasonic signal received by the piezoelectric element 4 is also attenuated and the signal waveform is deformed.

As a result, the S / N, which is the ratio of signal to noise, in the ultrasonic imaging apparatus is lowered, and the detection sensitivity and resolution are lowered. Further, since the piezoelectric element 4 cannot be downsized, it is difficult to integrate the piezoelectric element 4 to downsize the ultrasonic sensor unit 1 and improve the resolution.

According to the present invention, various amplifiers, switching devices, and controllers connected to a piezoelectric element for transmitting and receiving ultrasonic waves are formed by a heat-resistant and radiation-resistant vacuum micro element and are provided in the vicinity of the piezoelectric element, thereby achieving a small size. An object of the present invention is to provide an ultrasonic imaging device using an ultrasonic sensor unit having excellent detection sensitivity and resolution.

[0010]

In order to achieve the above object, an ultrasonic imaging apparatus according to the invention of claim 1 is installed in a reactor vessel of a liquid metal cooled reactor and immersed in the liquid metal. In a monitoring device for imaging a structure with ultrasonic waves, an ultrasonic sensor unit including a plurality of piezoelectric elements that emit and receive ultrasonic waves that are regularly arranged on a straight line or on the same plane is provided with the plurality of piezoelectric elements. A transmission and reception amplifier that amplifies signals transmitted and received by each piezoelectric element, a transmission and reception switcher that switches signals to the transmission and reception amplifier, and a controller that controls the transmission and reception switcher. The transmitting and receiving amplifiers, the transmitting and receiving switching devices, the controller, and the like are all provided in the vicinity of the piezoelectric element with heat resistance and radiation resistance.

In the ultrasonic imaging apparatus according to a second aspect of the present invention, in the ultrasonic sensor section, a transmission amplifier for amplifying signals supplied to a large number of piezoelectric elements for transmitting ultrasonic waves is heat resistant and radiation resistant. It is characterized in that it is composed of a vacuum micro-element. In the ultrasonic imaging apparatus according to the invention of claim 3, in the ultrasonic sensor section, a receiving amplifier for amplifying signals from a large number of piezoelectric elements that receive ultrasonic waves is a heat- and radiation-resistant vacuum micro It is characterized by being composed of an element.

In the ultrasonic imaging apparatus according to a fourth aspect of the present invention, in the ultrasonic sensor section, a transmission switch for switching the multiplex-transmitted signals and applying the signals to each piezoelectric element is heat-resistant and resistant. It is characterized in that it is composed of a radiation-type vacuum micro device. In the ultrasonic imaging apparatus according to the invention as set forth in claim 5, in the ultrasonic sensor section, a receiving switch for switching signals from each piezoelectric element for multiplex transmission is a heat- and radiation-resistant vacuum micro It is an element.

In an ultrasonic imaging apparatus according to a sixth aspect of the present invention, the controller for controlling the transmission / reception switch that switches the multiplex-transmitted signal and the signal from each piezoelectric element is heat and radiation resistant. It is a logic circuit configured by the vacuum micro element of. An ultrasonic imaging apparatus according to a seventh aspect of the invention is characterized in that a piezoelectric element for emitting and receiving ultrasonic waves is provided integrally with the transmitting amplifier composed of the heat-resistant and radiation-resistant vacuum micro element.

According to an eighth aspect of the invention, there is provided an ultrasonic imaging apparatus, wherein an oscillation and reception amplifier comprising the heat-resistant and radiation-resistant vacuum micro element, an oscillation and reception switcher,
It is characterized in that a controller and a piezoelectric element for emitting and receiving ultrasonic waves are integrated and integrated.

[0015]

According to the first aspect of the invention, the structure immersed in the liquid metal is generated by ultrasonic echoes generated and received by a large number of piezoelectric elements formed in the ultrasonic sensor section of the ultrasonic imaging apparatus. To be monitored. The piezoelectric element emits an ultrasonic echo when a high-voltage pulse amplified by a transmission amplifier is applied through a reception switching device controlled by a controller, and minute reception by an ultrasonic echo reflected from a structure. The signal is amplified by the receiving amplifier via a large number of piezoelectric elements.

A transmitter / receiver switch connected to the plurality of piezoelectric elements, a transmitter / receiver amplifier whose signals can be switched by the transmitter / receiver switch, and a controller for controlling the transmitter / receiver switch. Are provided near the piezoelectric element in liquid metal for heat resistance and radiation resistance.

For this reason, since the connection distance between the respective devices is short and the number of cables is small, the attenuation of the signals to be transmitted and received and the influence of noise are reduced, the S / N is improved, and the received signal is reproduced. The image of the object can be obtained clearly. Further, the ultrasonic sensor unit is downsized, and the inspection robot can be downsized by housing it in the inspection robot.

According to a second aspect of the present invention, the transmission amplifier installed in the vicinity of the piezoelectric element of the ultrasonic sensor section is a vacuum micro element having heat resistance and radiation resistance. Therefore, this transmission amplifier can be miniaturized with heat resistance and radiation resistance, and the ultrasonic sensor unit can be miniaturized.

According to a third aspect of the present invention, the receiving amplifier installed near the piezoelectric element of the ultrasonic sensor unit is heat-resistant,
Since the radiation-resistant vacuum micro element is used as an amplification amplifier due to its circuit configuration, the reception amplifier can be miniaturized with heat resistance and radiation resistance, and the ultrasonic sensor unit can be miniaturized.

According to a fourth aspect of the present invention, a heat transmission switch is installed near the piezoelectric element of the ultrasonic sensor unit,
Since it is a radiation-resistant vacuum micro-element and has a switching structure due to its circuit configuration, this transmission switching device can be miniaturized by heat resistance and radiation resistance, and the ultrasonic sensor unit can be miniaturized.

According to a fifth aspect of the present invention, the switch for reception installed near the piezoelectric element of the ultrasonic sensor unit is heat-resistant,
Since the radiation-resistant vacuum micro element is used as a switching device due to its circuit configuration, the receiving switching device can be miniaturized by heat resistance and radiation resistance, and the ultrasonic sensor unit can be miniaturized.

According to a sixth aspect of the present invention, the controller installed near the piezoelectric element of the ultrasonic sensor unit is heat-resistant,
Since the logic circuit is formed as a radiation-resistant vacuum micro element, the controller can be miniaturized with heat resistance and radiation resistance, and the ultrasonic sensor unit can be miniaturized.

According to a seventh aspect of the present invention, since the piezoelectric element of the ultrasonic sensor unit is integrally formed with a transmission amplifier composed of a heat- and radiation-resistant vacuum micro element, the function of transmitting and receiving ultrasonic echoes is provided. It is possible to improve the size of the ultrasonic sensor unit.

According to an eighth aspect of the present invention, the transmitter / receiver amplifier, the transmitter / receiver switch, and the controller are formed of heat- and radiation-resistant vacuum microelements, and the piezoelectric device emits and receives ultrasonic waves. By integrating and integrating with the element, the ultrasonic sensor portion is downsized and the S / N is improved, and the high density makes the directivity angle of the ultrasonic wave wide and the resolution improved.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. Note that the same components as those of the above-described related art are denoted by the same reference numerals, and detailed description thereof is omitted. The first embodiment is
As shown in the block diagram of FIG. 1, the ultrasonic wave transmission / reception control for each piezoelectric element 4 and the signal from each piezoelectric element 4 are combined outside the liquid metal 3 outside the inspection robot arm 2 by aperture synthesis. A signal processing device 5 for imaging is installed.

Further, the oscillator 6 is connected to the signal processing device 5 and multiplexes the voltage pulse signal of the ultrasonic wave based on the command of the signal processing device 5 and outputs it by one cable 17, and the piezoelectric elements. The received signals of No. 4 are multiplexed and input by one cable 17, and the A / D converter 15 for converting the analog signal into the digital signal and transmitting it to the signal processing device 5 and the image processing in the signal processing device 5. A display device 16 is provided for reproducing the image signal and making it observable.

The ultrasonic sensor 18 having a structure in which the portion immersed in the liquid metal 3 is resistant to high temperature and high level radiation due to the liquid metal 3 is attached to the tip of the inspection robot arm 2, for example. , Is immersed in the liquid metal 3 together with the inspection robot arm 2. On the surface of the ultrasonic sensor unit 18, a large number of piezoelectric elements 4 are regularly arranged in a plane.
The heat and radiation resistant controller 19 is also installed on the inspection robot arm 2 in the same manner.

Further, at the end of one cable 17 connected to the transmitter 6, a heat-resistant and radiation-resistant transmitter switch 20 composed of a plurality of switches corresponding to the plurality of piezoelectric elements 4 is provided. Are connected to the respective piezoelectric elements 4 via heat-resistant and radiation-resistant transmission amplifiers 21 each composed of a large number of amplification amplifiers. ing.

Further, the plurality of piezoelectric elements 4 and the A
Between the tip of one cable 17 connected to the D / D converter 15, a heat-resistant and radiation-resistant receiving switch 22 composed of a large number of switches corresponding to each piezoelectric element 4 and a large number of amplifiers. A heat-resistant and radiation-resistant reception amplifier 23, which is composed of a power amplifier, is connected. In addition, the heat and radiation resistant switching device
Both the heat-resistant and radiation-resistant receiving switch 20 and the heat-resistant and radiation-resistant receiving switch 22 are constructed so that their opening and closing are controlled by the heat-resistant and radiation-resistant controller 19.

Next, the operation of the above configuration will be described. A multiplexed voltage pulse signal is output from the transmitter 6 via the cable 17, and one of the heat and radiation resistant switching devices 20 is activated by the switching control command 8 from the heat and radiation resistant controller 19. Further, the heat-resistant and radiation-resistant receiving switch 22 other than the circuit corresponding to the heat-resistant and radiation-resistant transmitting switch 20 is closed.

For this purpose, one closed heat-resistant,
The voltage pulse signal output from the oscillator 6 is amplified by the heat-resistant and radiation-resistant transmission amplifier 21 in the circuit of the radiation-resistant transmission switch 20, and the high voltage pulse is immersed in the liquid metal 3. One of the many piezoelectric elements 4 in the ultrasonic sensor unit 18 installed at the tip of the inspection robot arm 2,
It is applied to the piezoelectric element 4 corresponding to the circuit.

As a result, the ultrasonic echo 11 is transmitted from the surface of the piezoelectric element 4 into the liquid metal 3, and the transmitted ultrasonic echo 11 is reflected from the object 12 and the plurality of ultrasonic sensor units 18 are provided. Alternatively, it is received by all the piezoelectric elements 4.
Note that the switching control command 8 from the heat and radiation resistant controller 19 is such that a plurality of switches in the heat and radiation resistant transmitting switch 20 and the heat and radiation resistant receiving switch 22 are combined in a predetermined combination. Open and close accordingly.

As a result, the large number of piezoelectric elements 4 in the ultrasonic sensor section 18 transmit and receive the ultrasonic echo 11 each time, and the received minute received signals are the circuits corresponding to the respective piezoelectric elements 4. Is input to the heat and radiation resistant reception amplifier 23 via the heat and radiation resistant receiving switch 22, and is amplified and multiplexed in each cable to form a single cable.
It is transmitted from 17 to the A / D converter 15 installed outside the liquid metal 3.

The signal converted by the A / D converter 15 is
The image of the object 12 is imaged in the signal processing device 5, and this image signal can be reproduced on the display device 16 to observe the image of the object 12.
The state of various objects 12 installed in the opaque liquid metal 3 in the furnace can be monitored.

In the above operation, the heat and radiation resistant controller 19 sequentially switches one piezoelectric element 4 for transmission when the number of the piezoelectric elements 4 in the ultrasonic sensor section 18 is N, for example. At the same time, the remaining N-1 piezoelectric elements 4 are always selected for reception, and these received signals are taken into the A / D converter 15 and transmitted to the signal processing device 5.

As a result, an image can be reproduced and displayed on the display device 16 by subjecting the enormous amount of captured ultrasonic echo 11 data to aperture synthesis. Also,
Heat resistant / radiation resistant transmitter 20 and heat resistant / radiation resistant amplifier 21 and heat resistant / radiation resistant receiver 22 and heat resistant,
The radiation-resistant receiving amplifier 23 and the heat-resistant and radiation-resistant controller 19 are all arranged close to the ultrasonic sensor section 18 in the inspection robot arm 2, and the S / N is improved by shortening the mutual wiring distance. To do.

The above heat and radiation resistant switching device
20 and a heat / radiation resistant transmission amplifier 21, a heat / radiation resistant receiving switch 22, a heat / radiation resistant receiving amplifier 23, and a heat / radiation resistant controller 19 are arranged as close to the piezoelectric element 4 as possible. The integration with the ultrasonic sensor unit 18 is facilitated.

Further, since the signals are multiplexed and transmitted and received with a small number of cables 17, the inspection robot arm 2
It is possible to suppress the number of cables 17 penetrating through the housing and the storage space as much as possible, and the resolution can be improved by increasing the number of the piezoelectric elements 4 arranged in the ultrasonic sensor section 18.

Further, since the heat-resistant / radiation-resistant receiving amplifier 23 and the heat-resistant / radiation-resistant transmitting amplifier 21 are close to the ultrasonic sensor section 18, signal attenuation is small, and conventionally, the capacitance of the cable 17 causes a piezoelectric element. Although there was a limit to miniaturization of 4, it will not be affected. As a result, the piezoelectric element 4 can be downsized and integrated, so that the directivity angle can be widened and the frequency can be increased to improve the ultrasonic waveform.
Moreover, the resolution of the ultrasonic image is improved by improving the S / N.

In the second embodiment, the heat-resistant and radiation-resistant transmitting switch 20 and the heat-resistant and radiation-resistant receiving switch 22 arranged in the liquid metal 3 and the heat-resistant and radiation-resistant receiving amplifier 23 and the heat-resistant, Since the radiation resistant transmission amplifier 21 and the heat and radiation resistant controller 19 receive a high level of radiation at a high temperature due to the liquid metal 3 of the core coolant, it is necessary to endure this environment.

Further, by miniaturizing and integrating each device as much as possible, the above-described effect of improving the function can be obtained. As a means for this, as shown in the sectional configuration diagram of FIG. 2, all the equipment and functions can be achieved by the vacuum micro device 24.

The vacuum micro-element 24 faces the flat-plate anode 25 in vacuum and has an emitter 26 having a sharp tip.
A gate 27 is provided between the gate and the gate, and they are electrically insulated from each other by an insulating layer 28. Further, since a minute space of the vacuum space 30 is formed between the tip of the emitter 26 and the anode 25, and a DC voltage is applied by the DC power supply 29, the emitter 26
A strong electric field is formed between the tip of the anode and the anode 25.

Therefore, the current between the anode 25 and the emitter 26 changes greatly only by applying a weak point pressure to the gate 27, so that it is possible to perform a signal amplifying action and a switching function. Also, the anode 25 and the emitter
Since the vacuum micro-elements 24 such as 26 and the insulating layer 28 are all made of metal or ceramic, they are characterized by excellent heat resistance and radiation resistance. It has the ability to withstand high levels of radiation.

The circuit diagram of FIG. 3 (a) and the characteristic diagram of FIG. 3 (b) are examples of the basic type configuration for amplifying and switching the vacuum micro device 24. In this vacuum micro device 24, the input to the circuit is the gate input voltage Y as shown in FIG. 3A, and the output takes out the current between the anode 25 and the emitter 26 as the output voltage Z by the load resistor 31. Note that reference numeral 32 indicates ground.

The operating characteristics of this circuit are shown in FIG. 3B. When the gate input voltage Y is applied in the amplification region U, it functions as an amplifier for amplification, and when the gate input voltage Y is added to the switching region V, the switching device is operated. Work as. Thus, by adjusting the gate input voltage Y of the vacuum micro element 24, the heat-resistant / radiation-resistant transmitting switch 20 and the heat-resistant / radiation-resistant receiving switch 22 and the heat-resistant / radiation-resistant transmitting amplifier
It is easy to realize 21 and the heat-resistant and radiation-resistant receiving amplifier 23.

In order to realize the heat-resistant and radiation-resistant controller 19 with this vacuum micro-element 24,
It is necessary to form a logic circuit. Generally, a logic circuit can be configured by combining AND, OR and inversion logic. Next, a configuration example of AND, OR and inversion logic by the vacuum micro element 24 will be shown.

The circuit diagram of FIG. 4A and the characteristic diagram of FIG.
In an example in which an inversion logic circuit is configured by the vacuum micro device 24, two DC power supplies 29a and 29b, and the load resistor 31, when the gate input voltage Y is not applied in the figure (logically 0), the anode is The output voltage Z is a positive power supply voltage (logically 1) because no current flows between 25 and the emitter 26.

However, when the gate input voltage Y is applied to the level of the switching region V (logically 1), the current between the anode 25 and the emitter 26 rises sharply, so that the load resistance 31 is set to an appropriate value or more. As a result, the output voltage Z becomes 0 (logically 0) and the inversion logic is established.

Based on the same principle, the circuit diagram of FIG.
The characteristic diagram of (b) shows two vacuum micro devices 24a and 24b.
The circuit diagram of FIG. 6A and the characteristic diagram of FIG. 6B show an example in which an OR logic circuit is configured by a DC power supply 29, a DC power supply 29, and a load resistance 31.
AND with 24a, 24b, DC power supply 29, and load resistance 31
The structural example of a logic circuit is shown.

As described above, the vacuum micro-element 24 is used to combine the basic circuits of inversion, OR, and AND logic of FIGS. Circuits can be built.

The third embodiment relates to the integration of the ultrasonic sensor section 18, and as shown in the circuit diagram of FIG. 7, the piezoelectric element 4 is incorporated in the heat-resistant and radiation-resistant receiving amplifier 22 by the vacuum micro-element 24. This is an example in which the vacuum micro-element 33 with a piezoelectric element is configured by.

Here, as a method of incorporating the piezoelectric element 4 into the anode 25 of the vacuum micro element 24, the piezoelectric element 4 is directly joined to the anode 25 (made of metal) by brazing, or niobate is placed on the anode 25. This is realized by a method of forming a piezoelectric element 4 by growing a material of a piezoelectric element such as a single crystal of lithium or lead titanate in a vapor phase or a liquid layer. As a result, the piezoelectric element 4 and the heat-resistant and radiation-resistant reception amplifier 22 in the ultrasonic sensor section 18 are easily integrated into a small size, and the S / N characteristic is also improved.

Further, by integrating the vacuum micro-elements 24, the heat-resistant and radiation-resistant transmission switch 20 and heat-resistant and radiation-resistant switching switches 20 which are composed of a large number of switches corresponding to a large number of piezoelectric elements 4 in the ultrasonic sensor section 18. Switch 21 for reception, and heat and radiation resistant amplifier 21 consisting of many amplifiers
The heat-resistant and radiation-resistant receiving amplifier 23 and the heat-resistant and radiation-resistant controller 19 can be downsized, and the ultrasonic sensor unit 18 can be integrated and downsized.

[0054]

As described above, according to the present invention, in the ultrasonic sensor unit of the ultrasonic imaging apparatus in the liquid metal cooling type fast breeder reactor, the switch for emitting and receiving, the amplifier for emitting and receiving and the controller are heat and radiation resistant. Since it can be downsized and the number of cables can be reduced, it can be integrated with the ultrasonic sensor unit, and can be housed in, for example, an inspection robot arm, which also contributes to downsizing of the inspection robot.

Further, by increasing the number of piezoelectric elements in the ultrasonic sensor section, the directivity angle of ultrasonic waves can be widened, the number of ultrasonic data for reproducing an ultrasonic image is increased, and the number of cables and their lengths are increased. Noise is further reduced by reducing the
There is an effect that N and the resolution of the image are improved.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an ultrasonic imaging apparatus according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional configuration diagram of a vacuum micro device according to an embodiment of the present invention.

FIG. 3A is a circuit diagram and FIG. 3B is a characteristic diagram of an amplification and switching circuit of a vacuum micro device according to an embodiment of the present invention.

FIG. 4A is a circuit diagram and FIG. 4B is a characteristic diagram of an inversion logic using a vacuum micro device according to an embodiment of the present invention.

5A and 5B are OR logics by a vacuum micro device of one embodiment according to the present invention, FIG. 5A is a circuit diagram, and FIG. 5B is a characteristic diagram.

6A and 6B are AND logics of a vacuum micro device according to an embodiment of the present invention, wherein FIG. 6A is a circuit diagram and FIG. 6B is a characteristic diagram.

FIG. 7 is a circuit diagram of a vacuum micro device with a piezoelectric device according to an embodiment of the present invention.

FIG. 8 is a block configuration diagram of a conventional ultrasonic imaging apparatus.

[Explanation of symbols]

1, 18 ... Ultrasonic sensor part, 2 ... Inspection robot arm, 3
... Liquid metal (sodium), 4 ... Piezoelectric element, 5 ... Signal processing device, 6 ... Oscillator, 7 ... Controller, 8 ... Switching control command, 9 ... Oscillating switch, 10 ... Oscillating amplifier, 11 ... Ultrasonic wave Echo, 12 ... Object, 13 ... Receiving switcher, 14 ... Receiving amplifier, 15 ... A / D converter, 16 ... Display device, 17 ... Cable, 19 ... Heat resistant, radiation resistant controller, 20 ... Transmitting heat resistant , Radiation resistant switch, 21 ... heat resistant for transmission, radiation resistant amplifier, 22 ... heat resistant for reception, radiation resistant switch, 23 ... heat resistant for reception, radiation resistant amplifier, 24, 24a, 24b ... vacuum micro device, 25 ... anode , 26 ... Emitter, 27 ... Gate, 28 ... Insulating layer, 29, 29a, 29b ... DC power supply, 30 ... Vacuum space, 31 ...
Load resistance, 32 ... Ground, 33 ... Vacuum micro device with piezoelectric element, U ... Amplification area, V ... Switching area, Y ... Gate input voltage, Y ₁ ... First gate input voltage, Y ₂ ... Second gate input voltage, Z ... Output voltage.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Takehiko Suzuki 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Toshiba Research & Development Center (72) Inventor Satoshi Nagai 2 Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa 4-chome, Toshiba Keihin Works (72) Inventor Yukinori Fumi, 8 Shinsita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Yokohama Corporation, Toshiba Corporation

Claims (8)

[Claims] 1. A monitoring device for ultrasonically imaging a structure immersed in a liquid metal, which is installed in a reactor vessel of a liquid metal cooled nuclear reactor, and is regularly arranged on a straight line or on the same plane. The ultrasonic sensor unit composed of a large number of piezoelectric elements for transmitting and receiving the ultrasonic waves, the large number of piezoelectric elements, a transmission and reception amplifier for amplifying signals transmitted and received by each piezoelectric element, and a transmission and reception amplifier It consists of a transmitter / receiver switcher that switches the signal to the amplifier and a controller that controls these transmitter / receiver switchers. The transmitter / receiver amplifier, transmitter / receiver switcher and controller are both heat-resistant and resistant. An ultrasonic imaging device, which is provided in the vicinity of the piezoelectric element due to radiation. 2. In the ultrasonic sensor section, a transmission amplifier for amplifying a signal supplied to a large number of piezoelectric elements for transmitting the ultrasonic wave is composed of a heat-resistant and radiation-resistant vacuum micro element. The ultrasonic imaging apparatus according to claim 1. 3. In the ultrasonic sensor section, a receiving amplifier for amplifying signals from a large number of piezoelectric elements that receive the ultrasonic wave is composed of a heat- and radiation-resistant vacuum micro element. The ultrasonic imaging apparatus according to claim 1. 4. In the ultrasonic sensor section, a transmission switching device for switching the multiplex-transmitted signals and applying them to each piezoelectric element comprises a heat- and radiation-resistant vacuum micro element. The ultrasonic imaging apparatus according to claim 1. 5. In the ultrasonic sensor section, a reception switch for switching signals from the respective piezoelectric elements for multiplex transmission is a heat-resistant and radiation-resistant vacuum micro element. Item 2. The ultrasonic imaging apparatus according to item 1. 6. A controller for controlling a switching device for transmitting and receiving, which switches between the multiplex-transmitted signal and the signal from each piezoelectric element, is a logic circuit composed of a heat-resistant and radiation-resistant vacuum micro element. The ultrasonic imaging apparatus according to claim 1, which is characterized in that 7. The ultrasonic imaging apparatus according to claim 2, further comprising a piezoelectric element for transmitting and receiving ultrasonic waves, which is integrated with the transmitting amplifier including the heat-resistant and radiation-resistant vacuum micro element. 8. A transmitter / receiver amplifier comprising the heat-resistant and radiation-resistant vacuum micro device, a transmitter / receiver switch, a controller, and a piezoelectric device for transmitting and receiving ultrasonic waves are integrated and integrated. The ultrasonic imaging apparatus according to any one of claims 2 to 7, wherein: