JP6443994B2 - Portable X-ray inspection equipment - Google Patents

Description

  The present invention relates to a portable X-ray inspection apparatus with high resolution used for a small, thin, and light X-ray nondestructive inspection.

  Many buildings and structures that have been built during the period of high growth and are the foundations of society and industry are still in use. In order to ensure these safety, the need for nondestructive inspection in the field is increasing.

  For example, as shown in FIG. 12, in a pipeline 10 such as a chemical plant or power plant constructed and manufactured in a high growth period, corrosion or thinning of the inner pipe 10b of the pipe 10a with the heat insulating material 10c becomes a problem. Yes. Therefore, an X-ray transmission method is used to inspect the corrosion of the pipe 10a without removing the heat insulating material 10c.

  However, the conventional X-ray source 2 'is large in size, heavy, and has poor workability on site due to the limitations of the need for power supply wiring, and a narrow space (70 mm) where many pipes are installed. However, it was difficult to use in FIG. Therefore, a small X-ray source 2 that can be used even in a narrow space has been demanded.

  In addition, a structure such as a plant such as a pipeline 10 has a long and large number of inspection targets, and is mounted on a robot or the like for inspection while moving to reduce the X-ray exposure of workers and increase work efficiency. A compact and lightweight X-ray source 2 is also desired. Furthermore, there is a need for a long-life X-ray source that does not require long-term replacement even if the X-ray source is overused and a large number of non-destructive inspections are performed.

  On the other hand, Patent Document 1 is disclosed as a nondestructive inspection apparatus for nondestructive inspection of piping. The nondestructive inspection apparatus 1a of Patent Document 1 radiates radiation such as X-rays and γ rays to the pipe 2 to be inspected in order to reduce the installation space of the nondestructive inspection apparatus for piping and shorten the inspection time. Radiation source 3, a color image intensifier 6 that receives the radiation emitted from the radiation source 3 and transmitted through the pipe 2, and the radiation source 3 to be opposed to each other across the pipe 2. I. A positioning mechanism 5 for positioning the relative position and posture with respect to 6; I. 6 includes an image processing device 7 that performs image processing by decomposing the color signal output from each wavelength component.

  However, the invention of Patent Document 1 can be inspected as long as the pipe has a specific shape and structure, but there is a problem in that it is not versatile. In addition, the application range to other inspection objects is also narrow. Regarding the X-ray source, there is no disclosure regarding the specific structure and characteristics regarding long life, high resolution, and low running cost.

JP 2008-51653 A JP 2012-133897 A

http://beam-physics.kek.jp/bpc/procs/suzuki.pdf “Development and application of dry cell-powered micro-electron accelerator and high-energy X-ray source” 29 March 2009 Ryoichi Suzuki Industrial Technology Center Institute " http://www.aist.go.jp/aist_j/press_release/pr2014/pr20140603/pr20140603.html "Development of a compact and lightweight pulse X-ray source for nondestructive inspection"

  Therefore, the present invention is a portable X that is versatile and can be applied to various shapes and structures to be inspected, which is used for X-ray non-destructive inspection which is small, thin and light, has high resolution and low running cost. An object is to provide a line inspection apparatus.

In order to solve the above problems, the present invention provides:
(1)
A portable X-ray inspection device that generates X-rays with high output pulses while being small, thin and light, and is used for X-ray non-destructive inspection.
A power source, an X-ray tube that irradiates the inspection target with X-rays, a high-voltage circuit group that generates a pulse high voltage to be applied to the X-ray tube by a plurality of booster circuits, An X-ray source having a built-in drive circuit that variably controls the generation timing and pulse width to determine the X-ray irradiation timing;
A digital X-ray detector that senses the X-ray transmitted through the inspection object in synchronization with the X-ray generation timing of the X-ray source;
A control device for processing the detection signal of the X-ray detector so as to be displayed and stored as a digital image;
A monitor for displaying the digital image;
Tona is,
The high voltage circuit group is:
A first-stage high-voltage circuit including a DC-DC converter circuit that boosts 1.2 V to 6 V to DC 50 V to 80 V;
A second-stage anode high-voltage circuit including a DC-AC converter circuit of a winding small transformer that further boosts the voltage boosted to DC 50 V to 80 V to AC 8 kV to 15 kV;
A second-stage cathode high-voltage circuit including a DC-AC converter circuit of a winding small transformer that further boosts the voltage boosted to DC 50 V to 80 V to AC 5 kV to 10 kV;
A third-stage anode high voltage comprising a multi-stage Cockcroft-Walton circuit, which is composed of a capacitor and a diode, further boosting the voltage on the anode side boosted to 8 kV to 15 kV to 50 kV to 100 kV, and optimized for the X-ray tube Circuit,
A third-stage cathode including a multistage Cockcroft-Walton circuit, which is composed of a capacitor and a diode, further boosting the cathode-side voltage boosted to 5 kV to 10 kV to 40 kV to 80 kV, and optimized for the polar X-ray tube A high voltage circuit,
A portable X-ray inspection apparatus characterized by comprising:
( 2 )
The portable X-ray inspection apparatus according to (1), wherein the X-ray detector detects an X-ray by a wired or wireless synchronization signal in synchronization with an X-ray irradiation timing.
( 3 )
In the synchronization, the control device sends a trigger, which is an X-ray inspection start signal, to the X-ray source and the X-ray detector by wire or wirelessly, receives the trigger, and the X-ray source emits X-rays. The portable X-ray inspection apparatus according to ( 2 ), wherein the X-ray detector starts detection of the X-ray.
( 4 )
The drive circuit performs control to vary one or more of the value of the pulse high voltage, the pulse width, and the number of pulses, and makes the X-ray dose variable (1) Portable X-ray inspection apparatus as described in 1.
( 5 )
The X-ray source is
The X-ray tube, a main body made of an insulating mold that covers the X-ray tube, and a final-stage booster circuit of the plurality of booster circuits, an operation unit including the power supply and the drive circuit,
The main body and the operation unit are separated, connected by wire or wirelessly, by remote operation,
Control is performed to vary the value of the pulse high voltage, the pulse width, and the number of pulses, X-rays are generated at a location distant from the operation unit, and the X-ray irradiation dose is variable ( The portable X-ray inspection apparatus according to 1).
It was.

  Since this invention is the above structure, the following effects are exhibited. A compact, lightweight and portable X-ray inspection device that is small, thin and light, used for non-destructive X-ray inspection, can be applied to various shapes and structures of inspection objects with high resolution and low running cost. Can provide.

  More specifically, by synchronizing X-ray irradiation and detection, the detector is operated only when X-rays are irradiated, so the detector background noise that occurs while X-rays are not irradiated is reduced. Since the noise component is reduced and the S / N (Signal / Noise) is improved, the inspection result can be acquired as a high resolution image (beautiful image). In addition, a compact and lightweight X-ray source with a thickness of 70 mm or less and a weight of 6 kg or less can be realized. Furthermore, if an X-ray detector and a monitor are combined and mounted on a robot, etc., X-ray generation and data communication are made wireless communication. Efficient nondestructive X-ray inspection can be performed safely even in high places and narrow spaces. This greatly reduces inspection costs and running costs.

  By using an aged carbon nanostructure as an electron source, it is possible to irradiate X-rays immediately without the need for preheating, power savings that can be driven by a dry cell, and further extending the life of the carbon nanostructure X-ray tube. Even if the site is used frequently, it is not necessary to replace the X-ray tube for a long time.

  In addition, by optimizing the high voltage circuit with a multi-stage booster circuit, even a power source such as a dry battery can generate high output pulse X-rays in a short time on the order of milliseconds, and for pulse irradiation, The power supply and booster circuit are small and external leakage can be minimized, so that moving objects can be imaged and X-ray sources can be moved while moving, expanding the application range of X-ray inspection.

It is a block diagram of the portable X-ray inspection apparatus which is this invention. It is explanatory drawing of the imaging method in the portable X-ray inspection apparatus which is this invention. It is the test result of the pipe | tube which coat | covered the inner pipe | tube with the jacket and the heat insulating material image | photographed with the portable X-ray inspection apparatus which is this invention. Artificial scratches (slits) can be confirmed in the white frame. It is a block diagram of the portable X-ray inspection apparatus which is this invention. It is the external appearance of a X-ray source, and the photograph of a storage thing. It is explanatory drawing and a photograph of high voltage. It is an example of a third stage anode / cathode booster circuit diagram. It is explanatory drawing of a synchronization of X-ray irradiation and the detection timing of an X-ray detector. It is an X-ray imaging result of imaging objects other than piping. (A) is a board | substrate accommodated in the housing | casing, (B) is a picked-up image of a human hand. It is explanatory drawing of an X-ray tube (carbon nanostructure triode-type cold cathode X-ray tube). It is a microscope picture of the carbon nanostructure cold cathode electron source surface. It is explanatory drawing of the inspection method of piping by the conventional nondestructive X-ray inspection apparatus. It is description (A) of a separated X-ray source, and a real photograph (B).

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to these embodiments.

  As shown in FIGS. 1 and 4 and the like, a portable X-ray inspection apparatus 1 which is an example of the present invention includes an X-ray source 2, an X-ray detector 3, and a PC 4 including a monitor 4d and a control device 4a. In the present invention, for example, the X-ray 2a is irradiated to the pipe 10a without removing the jacket 10d and the heat insulating material 10c from the pipe 10a, and the deterioration of the internal tube 10b covered with the heat insulating material 10c is X-ray photographed ( The inspection image 4e) can be confirmed (X-ray nondestructive inspection). The X-ray source 2 and the X-ray detector 3 can also be controlled by the wireless communication 6 and 7 by the PC 4.

  As shown in FIG. 2, when the inspection object is a pipe 10a, the whole pipe is irradiated with the X-ray 2a from the X-ray source 2 as shown in FIG. It is also possible to take an image through the vessel 3, and as shown in (B), to take an image of the edge 10e and inspect the thickness of the inner tube 10b. The imaging result (inspection image 4e) of the edge 10e shown in FIG. 2B is shown in FIG.

  As shown in FIG. 3, in the X-ray nondestructive inspection (imaging) of the pipe 10a using the X-ray source 2 and the X-ray detector 3, the boundary between the inner tube 10b covered with the heat insulating material 10c and the heat insulating material 10c. The edge 10e portion can be clearly confirmed as a boundary between the inner tube image 4f and the heat insulating material image 4g, and a flaw (slit 4h) artificially formed in the inner tube 10b can also be clearly confirmed.

Hereinafter, the configuration of the portable X-ray inspection apparatus 1 which is an example of the present invention will be described in detail.

  The X-ray source 2 irradiates the inspection object 11 with the X-ray 2a. As shown in FIG. 4-6, the battery 2b, the drive circuit 2q, the high-voltage circuit group 2c, and the X-ray tube 5 Become. They are covered with an insulating mold and built in the housing 2r. The housing 2r is provided with an operation unit 2f and an antenna 2e. The antenna 2 e of the X-ray source 2 is used for wireless communication 6 between the PC 4 and the X-ray source 2.

  The X-ray source 2 is also driven by a voltage (1.2 V) of one dry battery (battery 2b), and outputs an X-ray 2a having a radiation energy level sufficient to take a clear X-ray image of the pipe 10a (100 keV). However, in order to withstand driving for a longer time, a lithium battery of 6V or the like may be employed.

  The drive circuit 2q controls the generation of the pulse high voltage 2p applied to the X-ray tube 5, varies the value of the pulse high voltage, the pulse width, and the number of pulses, and variably controls the irradiation amount of the X-ray 2a. The operation unit 2f is a button for inputting installation of the drive circuit 2q.

  As shown in FIG. 6, the high voltage circuit group 2c is connected to a battery (B) a first stage high voltage circuit 2g, a second stage anode high voltage circuit 2h, and a second stage cathode high voltage circuit 2i; C) It comprises a third stage anode booster circuit 2k and a third stage cathode booster circuit 2n, and (D) a pulse high voltage 2p is applied to the X-ray tube 5. With reference to FIG. 6, a mechanism for generating a pulse high voltage 2p in the range of AC 100 kV to 150 kV from 1.2 V to 6 V in combination with the anode and the cathode will be described.

  The first stage high voltage circuit 2g includes a booster circuit using a DC-DC converter, and boosts the voltage (1.2V to 6V) of the dry battery (battery 2b) to DC50V to 80V.

  The second-stage anode high-voltage circuit 2h is a second-stage booster circuit for the voltage applied to the anode of the X-ray tube 5, includes a booster circuit using a DC-AC converter using a transformer, and has an input voltage of approximately DC80V. Is raised to approximately AC 15 kV.

  The second-stage cathode high-voltage circuit 2i is a second-stage booster circuit for the voltage applied to the cathode of the X-ray tube 5, and includes a booster circuit using a DC-AC converter using a transformer in the same manner as the anode. The input voltage of about DC80V is boosted to about AC10kV.

  The third-stage anode booster circuit 2k is a third-stage booster circuit for the voltage applied to the anode of the X-ray tube 5 and includes a circuit whose number of stages is optimized by a multistage Cockcroft-Walton circuit. The input voltage is boosted to approximately AC 100 kV.

  The third-stage cathode booster circuit 2n is a third-stage booster circuit for the voltage applied to the cathode of the X-ray tube 5 and, like the anode, is a circuit in which the number of stages is optimized by a multistage Cockcroft-Walton circuit. The input voltage of approximately AC 10 kV is boosted to approximately AC 80 kV.

  A circuit diagram of the third stage anode / cathode booster circuits 2k, 2n is shown in FIG. As shown in FIG. 7, the third stage anode / cathode booster circuits 2k, 2n are composed of capacitors and diodes, and are characterized in that the number of stages is optimized in accordance with the characteristics of the cold cathode X-ray tube.

  By passing through these circuits, the voltage (1.2V to 6V) of the dry battery is applied to the X-ray tube 5 as a pulse high voltage 2p of approximately AC 150 kV, and the X-ray 2 a of 150 keV can be emitted.

  As shown in FIG. 4, the X-ray detector 3 is arranged at a position sandwiching the inspection object 11 with the X-ray source 2, and senses the X-ray 2a transmitted through the inspection object 11 as digital two-dimensional image data. Then, the signal is transmitted to the control device 4a by the wireless communication 6 through the antenna 3a of the wired / X-ray detector 3.

  Examples of the X-ray detector 3 include a scintillator, a CCD, a CMOS, and a CdTe semiconductor.

  As shown in FIGS. 1 and 4, the PC 4 includes a monitor 4d and a control device 4a. Data acquired by the X-ray detector 3 is processed into data that can be displayed on the monitor 4d by the control device 4a. Thus, the X-ray image (inspection image 4e) of the inspection object 11 can be confirmed in real time. Of course, the acquired data and the inspection image 4e can be stored in a recording medium. The control device 4a includes a synchronization generation unit 4b that generates a trigger 4c that controls the synchronization of irradiation of an X-ray 2a described later and detection start of the X-ray detector 3.

  Next, with reference to FIG. 8, the synchronization mechanism of X-ray 2a irradiation and detection start of the X-ray detector 3 will be described. The synchronization generator 4b of the control device 4a receives the start signal, sends a trigger 4c, which is an X-ray inspection start signal, to the X-ray source 2 (drive circuit 2q) and the X-ray detector 3, and receives the trigger 4c. The X-ray source 2 irradiates the X-ray 2a, and the X-ray detector 3 starts detection of the X-ray 2a in anticipation of a time loss from the trigger 4c to the X-ray 2a irradiation. Thereby, while suppressing the noise of the test | inspection image 4e, it contributes to the exposure reduction of the surrounding environment.

  Thereafter, the acquired imaging data is sent to the PC 4 by the wireless communication 7 between the X-ray detector 3 and the PC 4, subjected to image processing by the control device 4a, and displayed on the monitor 4d as the inspection image 4e. .

  The present invention thus configured is not limited to the pipe 10a, but as shown in FIG. 9A, the photographing and inspection of the circuit housed therein, as shown in FIG. It can also be used for X-ray photography and has a very wide general-purpose range. In addition, the pulse interval can be arbitrarily set from 1 ms to 1000 ms, etc., so that a continuous still image of an inspection object that moves at high speed can be used to capture a clear still image, and a continuous reproduction of the inspection image makes it possible to It can also be confirmed.

  Next, the X-ray tube will be described. As shown in FIG. 10, as the X-ray tube 5, for example, there is a carbon nanostructure triode cold cathode X-ray tube 5a, etc., which is small in size and receives a pulse high voltage 2p, and on the cathode 5b side. Electrons 5e generated at the carbon nanostructure cold cathode 5d are irradiated onto the target 5f on the anode 5c side to generate X-rays 2a, which are emitted from the emission port 5g. Note that the principle and configuration in which the X-ray tube 5 is driven by a dry cell, a battery, and a commercial power source are described in detail in Patent Document 2 and Non-Patent Document 1.

  The carbon nanostructure tripolar cold cathode 5a used in the present invention is, for example, as shown in FIG. 11, tapered as a whole toward the tip where random carbon nanotubes, carbon nanowool, and nanodiamond are mixed. Electrons 5e are emitted to a target 5f that generates X-rays 2a. However, it is not limited to this shape. The lifetime of the carbon nanostructure cold cathode is extended by, for example, aging treatment that gradually applies voltage and current to the cold cathode to stabilize the properties of the cold cathode.

  FIG. 13 illustrates a second embodiment of the X-ray source separation type of the portable X-ray inspection apparatus 21 according to the present invention.

The X-ray source 22 includes an X-ray tube 5, a main body 22 a made of an insulating mold that covers the X-ray tube 5,
A final stage booster circuit among a plurality of stage booster circuits, a power source such as a battery 2b, and an operation unit 22f including a drive circuit 2q.
The main body 22a and the operation unit 2f are separated and connected, for example, by a wired or wireless connection such as a cord 22b.
Control is performed to vary the value of the pulse high voltage, the pulse width, and the number of pulses, X-ray 2a is generated at a location distant from the operation unit 22f, and the irradiation amount of X-ray 2a is varied. Thereby, versatility is high, exposure is avoided, and it becomes a safe X-ray inspection apparatus. The X-ray detector 3 can also be synchronized with the irradiation of the X-ray 2a by the wireless communication 6a, 7a via the PC 4 and the antenna 23a of the wireless device 23. The PC 4 and the wireless device 23 are electrically connected by communication 23b.

DESCRIPTION OF SYMBOLS 1 Portable X-ray inspection apparatus 2 X-ray source 2 'Conventional X-ray source 2a X-ray 2b Battery 2c High voltage circuit group 2e Antenna 2f Operation part 2g First stage high voltage circuit 2h Second stage anode high voltage circuit 2i Two-stage cathode high voltage circuit 2k Third stage anode boost circuit 2n Third stage cathode boost circuit 2p Pulse high voltage 2q Drive circuit 2r Housing 3 X-ray detector 3a Antenna 4 PC
4a Control device 4b Trigger generator 4c Trigger 4d Monitor 4e Inspection image 4f Inner tube image 4g Thermal insulation image 4h Slit 5 X-ray tube 5a Carbon nanostructure Tripolar cold cathode X-ray tube 5b Cathode 5c Anode 5d Carbon nanostructure Cold cathode 5e Electron 5f Target 5g Emission port 5h Middle pole 5i Hole 5k Ground 6 Wireless communication 6a Wireless communication 7 Wireless communication 7a Wireless communication 10 Pipeline 10a Pipe 10b Inner tube 10c Heat insulating material 10d Outer cover 10e Edge 11 Inspection object 21 Portable X X-ray source 22a Main body 22b Code 22f Operation unit 23 Radio 23a Antenna 23b Communication

Claims (5)

A portable X-ray inspection device that generates X-rays with high output pulses while being small, thin and light, and is used for X-ray non-destructive inspection.
A power source, an X-ray tube that irradiates the inspection target with X-rays, a high-voltage circuit group that generates a pulse high voltage to be applied to the X-ray tube by a plurality of booster circuits, An X-ray source having a built-in drive circuit that variably controls the generation timing and pulse width to determine the X-ray irradiation timing;
A digital X-ray detector that senses the X-ray transmitted through the inspection object in synchronization with the X-ray generation timing of the X-ray source;
A control device for processing the detection signal of the X-ray detector so as to be displayed and stored as a digital image;
A monitor for displaying the digital image;
Tona is,
The high voltage circuit group is:
A first-stage high-voltage circuit including a DC-DC converter circuit that boosts 1.2 V to 6 V to DC 50 V to 80 V;
A second-stage anode high-voltage circuit including a DC-AC converter circuit of a winding small transformer that further boosts the voltage boosted to DC 50 V to 80 V to AC 8 kV to 15 kV;
A second-stage cathode high-voltage circuit including a DC-AC converter circuit of a winding small transformer that further boosts the voltage boosted to DC 50 V to 80 V to AC 5 kV to 10 kV;
A third stage anode high voltage comprising a multi-stage Cockcroft-Walton circuit, which is composed of a capacitor and a diode, further boosting the voltage on the anode side boosted to AC8 k to 15 kV to AC 50 kV to 100 kV, and optimized for the X-ray tube Circuit,
A third-stage cathode including a multi-stage Cockcroft-Walton circuit, which is composed of a capacitor and a diode, and further optimizes the cathode-side voltage boosted to 5 to 10 kV AC to 40 to 80 kV, and is optimized for the polar X-ray tube A high voltage circuit,
A portable X-ray inspection apparatus characterized by comprising: The portable X-ray inspection apparatus according to claim 1, wherein the X-ray detector detects X-rays by a wired or wireless synchronization signal in synchronization with an X-ray irradiation timing. In the synchronization, the control device sends a trigger, which is an X-ray inspection start signal, to the X-ray source and the X-ray detector by wire or wirelessly, receives the trigger, and the X-ray source emits X-rays. The portable X-ray inspection apparatus according to claim 2 , wherein the X-ray detector starts detecting the X-ray. 2. The drive circuit performs control to vary any one or more of the value of the pulse high voltage, the pulse width, and the number of pulses, and makes the X-ray irradiation amount variable. Portable X-ray inspection apparatus as described in 1. The X-ray source is
The X-ray tube, a main body made of an insulating mold that covers the X-ray tube, and a final-stage booster circuit of the plurality of booster circuits, an operation unit including the power supply and the drive circuit,
The main body and the operation unit are separated, connected by wire or wirelessly, by remote operation,
The control is performed to vary the value of the pulse high voltage, the pulse width, and the number of pulses, X-rays are generated at a location away from the operation unit, and the X-ray irradiation amount is variable. Item 2. The portable X-ray inspection apparatus according to Item 1.