JP2011100637A - X-ray tube device and x-ray device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray tube device which, while having a micro focus, has little fear of causing a focal deviation even if a large current enabling a general photographing is supplied. <P>SOLUTION: The X-ray tube device 1 is provided with an X-ray tube container 2 enclosing an X-ray tube 4. The X-ray tube 4 has a negative electrode 44 containing three electron generation sources 446-448 generating electrons and focusing body 442 for focusing the electrons discharged from the electron generation sources into electron beams of a fine beam shape, and a focusing electrode 449, a positive electrode 46 which is arranged opposing the negative electrode and has a target 462 on the opposing surface of which the electron beam collides to form an X-ray source to emit X-rays, and an external envelope 42 for enclosing the negative electrode and the positive electrode in vacuum airtight. An X-ray source for large focuses is formed on the target 462 by two of the electron generation sources 446, 448 and moreover an X-ray generation source for micro focuse is formed by the one electron generation source 445. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an X-ray tube apparatus and an X-ray apparatus.

  An X-ray tube apparatus is mounted and used in an X-ray apparatus that performs examination or diagnosis of a subject. In the examination or diagnosis by the X-ray apparatus, first, X-rays are generated by the X-ray tube apparatus, the generated X-rays are irradiated to the subject, the dose of the X-rays transmitted through the subject is measured, and the measured dose is obtained. This is done by creating an X-ray image on the basis thereof.

  An X-ray apparatus equipped with an X-ray tube apparatus is widely used in a medical field for an X-ray fluoroscopy apparatus, an X-ray imaging apparatus, etc., and in an industrial field for a defect inspection or foreign object inspection of various products. .

  In such an X-ray tube apparatus, it is desirable to obtain an enlarged image of the inspection object as much as possible in order to perform a good inspection or diagnosis when the inspection object in the subject is very small. For this purpose, in the X-ray tube apparatus or the X-ray generator that interpolates the X-ray tube apparatus, it is necessary to reduce the size of the X-ray source (also referred to as a focal point) as an X-ray generation region as much as possible. Accordingly, there is an increasing demand for X-ray tube apparatuses having a micro focus.

  The conventional X-ray tube apparatus has a structure in which focal points having different sizes are formed on the anode. A small focal point is used for fluoroscopic imaging with a small X-ray dose, and a large focal point is used for general imaging with a high X-ray dose. In general photography, a large current is required compared to fluoroscopic photography.

  In the case of an X-ray tube apparatus having a micro focus, as an electron focusing method for obtaining an extremely small focus, an electron lens (hereinafter referred to as “focusing electrode”) is formed using a plurality of electrodes, and the electron beam is focused. The method is known. By adopting this structure, the small focal point can form a smaller micro focal point.

  However, the focus of an X-ray tube apparatus having a plurality of focal points is switched when switching from fluoroscopic imaging with different X-ray doses to general imaging and vice versa. At that time, it is necessary to reduce the deviation of the imaging position of the subject. For this reason, a method of reducing the focus shift by changing the shape of the focusing groove has been proposed (Patent Document 1).

JP 2001-135265 A

  However, with the conventional method described above, it is difficult to prevent large focal shifts in general imaging using a focusing electrode.

  In an X-ray tube apparatus having a micro focus, since X-ray tube apparatus lacks versatility only by fluoroscopic imaging, an X-ray tube apparatus capable of general imaging is desirable. Since the dose differs between fluoroscopic imaging and general imaging, a current several times that of fluoroscopic imaging is required for general imaging. A fluoroscopic filament usually does not have a wire diameter or number of turns sufficient to withstand a large current, and therefore cannot be used for general photography. For this reason, a filament for general photography is required in addition to the filament for fluoroscopy. However, when the fluoroscopic filament and the general imaging filament are each arranged in a single manner, the focusing electrode for forming a micro focus at the time of fluoroscopic imaging causes a focus shift of a large focal point at the time of general imaging. As a result, the positions of the micro focus and the large focus change, which hinders shooting.

  The problem to be solved by the invention is an X-ray tube apparatus that is less likely to cause a focus shift even when a large current is supplied so that general imaging can be performed while having a micro focus, and an X-ray apparatus including the apparatus Is to provide.

  The present invention solves the above problems by the following means. The following means for solving will be described with reference numerals corresponding to the drawings showing the embodiments of the invention. However, the reference numerals are only for facilitating the understanding of the invention and are not intended to limit the invention. .

An X-ray tube device (1, 1a, 1b, 1c) according to the invention is an X-ray tube device including an X-ray tube container (2) including an X-ray tube (4).
The X-ray tube (4) includes three or more electron generation sources (446 to 448) that emit electrons, and a focusing system (442, 442a,...) That focuses the electrons emitted from the electron generation sources into a narrow beam of electron beams. Cathodes (44, 44a) including 442b, 449, 449a);
An anode (46) having a target (462) disposed opposite to the cathode and forming an X-ray source that collides with an electron beam and emits X-rays on the opposite surface;
An envelope (42) for sealing the cathode and the anode in a vacuum-tight manner,
Two or more electron generation sources (446, 448) form a large focus X-ray source on the target, and one or more electron generation sources (447) form a microfocus X-ray source on the target. It is characterized by being formed.

In a first aspect, the focusing system of the cathode (44) is
A focusing body (442) in which focusing grooves (443 to 445) recessed backward with respect to the anode (46) are formed in the same number as the number of electron generation sources;
A focusing electrode (449) connected to the anode side end of the focusing body;
The first cathode (447) for forming a micro focus is disposed in the central groove (444) of the plurality of focusing grooves, and the grooves (symmetrical with respect to the central groove) ( 443, 445) are provided with second cathodes (446, 448) for forming a large focal point, respectively.

In the second aspect, the focusing system of the cathode (44a) is:
A first focusing body (442a) formed with a single focusing groove recessed backward with respect to the anode (46);
A focusing electrode (449a) connected to the anode side end of the first focusing body;
A second focusing body (442b) having a plurality of focusing grooves recessed backward with respect to the anode (46),
The first groove (447) for forming the micro focus is arranged in the single groove formed in the first focusing body, and the plurality of grooves formed in the second focusing body are in the plurality of grooves formed in the second focusing body. The second cathodes (446, 448) for forming a large focal point are arranged.

  The X-ray apparatus according to the invention is equipped with any X-ray tube apparatus (1, 1a, 1b, 1c).

  According to the above invention, since the X-ray source is formed by a plurality of electron generation sources, the X-rays formed by the plurality of electron generation sources to enable a large current required for general imaging. By using the source for the large focal point and using the X-ray source formed by the remaining electron generation source for the micro focal point, it is possible to prevent the occurrence of defocusing at both focal points.

  By providing multiple electron sources for large focal points, it is possible to prevent defocusing of both the large focal point and fine focal point X-ray sources on the anode from colliding with the electron beam from multiple directions of the cathode toward the anode. By doing so, it is possible to prevent the deviation of the focal spot for the large focal point at the anode, and to create a region A where the focal spot for the large focal point overlaps in the vicinity of the center of the focal spot for the fine focal point. It seems (see Fig. 6). As shown in FIG. 6, the center point of the region A becomes the center Cb1 of the focal plane with the large focal point, which coincides with the center Cs1 of the focal plane with the minute focal point, thereby preventing the focus shift.

  According to the above-described invention, it is possible to flow a large current for performing general imaging in an X-ray tube having a minute focus, and since the focus shift is small, a highly versatile X-ray tube can be realized.

FIG. 1 is a schematic view showing an X-ray tube apparatus according to an example of the present invention. FIG. 2 is an enlarged view of the main part showing the vicinity of the cathode constituting the X-ray tube used in the X-ray tube apparatus of FIG. 3 is a cross-sectional view of the main part of FIG. FIG. 4 is a view showing the vicinity of the cathode when FIG. 3 is viewed from the IV direction. FIG. 5 is an electron trajectory diagram when the cathode of FIGS. 2 to 4 is used. FIG. 6 is a diagram for explaining the focal trajectory of each focal point on the target inclined surface (focal plane) when FIG. 3 is viewed from the VI direction. FIG. 7 is an explanatory view corresponding to FIG. 6 in the case of using a conventional cathode. FIG. 8 is a schematic view showing an X-ray tube apparatus according to another example of the present invention. FIG. 9 is a view showing the vicinity of the cathode when FIG. 8 is viewed from the IX direction. FIG. 10 is a plan view of FIG. 8 viewed from the X direction. FIG. 11 is a left side view of FIG. 8 viewed from the XI direction. FIG. 12 is a schematic view showing an X-ray tube apparatus according to another example of the present invention. FIG. 13 is a schematic view showing an X-ray tube apparatus according to another example of the present invention. FIG. 14 is a schematic view showing an X-ray tube apparatus according to another example of the present invention.

  Hereinafter, an X-ray tube apparatus according to an embodiment of the present invention will be described with reference to the drawings.

<< First Embodiment >>
As shown in FIG. 1, an X-ray tube apparatus 1 according to the present embodiment includes a housing 2 that is a substantially cylindrical hollow body. The housing 2 (X-ray tube container) has a rectangular parallelepiped shape or a cylindrical shape, and is formed of a steel plate, an aluminum alloy casting, or the like. In the present embodiment, the housing 2 has an X-ray tube 4 capable of emitting X-rays with a predetermined intensity in a predetermined direction, and a high voltage X-ray between the anode 46 and the cathode 44 of the X-ray tube 4. A high voltage power source (not shown) for supplying the tube voltage, a cathode power source (not shown) for supplying the cathode heater heating voltage and other various voltages to the cathode 44 of the X-ray tube 4, and an anode of the X-ray tube 4 A stator 6 for rotating, a stator power source (not shown) for driving the stator 6, an X-ray tube support (not shown) for supporting the X-ray tube 4 on its inner wall, etc., an X-ray tube 4 and insulating oil (not shown) filled to insulate and cool the high voltage power source and the like, and bellows (not shown) attached to buffer expansion and contraction of the insulating oil are accommodated. The size of the cylindrical side surface of the housing 2 is adjusted so that the radiation window 43 of the X-ray tube 4 is disposed directly or in proximity to the cylindrical side surface. In addition, at least a portion close to the X-ray tube 4 on the inner wall surface of the housing 2 is subjected to X-ray prevention treatment.

  The stator 6 is disposed in the vicinity of the outer periphery of the rotor 464 of the anode 46 that is a constituent member of the X-ray tube 4 and is supported by the X-ray tube support.

  The high voltage power source includes a transformer, a rectifier circuit, and the like, and generates a positive high voltage supplied to the anode 46 of the X-ray tube 4 and a negative high voltage supplied to the cathode 44.

  The cathode power source includes a cathode heater power source (not shown) for heating a cathode (described later) heater of the cathode 44, a voltage power source, and the like. The cathode heater power source is composed of a transformer or the like, and the voltage power source is composed of a transformer and a rectifier circuit, or a transformer, a rectifier circuit, and a voltage regulator circuit. Since the output voltage from the cathode power supply is maintained at a negative high potential, an insulation transformer is usually used as the transformer used here.

  A high voltage (X-ray tube voltage) generated by the high voltage power source is supplied to the anode 46 and the cathode 44 of the X-ray tube 4 by a high voltage lead wire (not shown), and various voltages generated by the cathode power source are supplied from the high voltage power source. A high voltage of negative potential is supplied to the cathode 44 of the X-ray tube 4 by a high-voltage lead wire.

  The configuration of the stator power supply varies depending on the type of the stator 6 (whether it is single-phase or three-phase, etc.). Since the output voltage from the stator power supply is a low voltage, it is supplied to the stator 6 via a low-voltage lead wire (not shown).

  The bellows has, for example, a bowl shape, is made of rubber or the like, and is oil-tightly attached to the inner wall surface of the housing 2 to buffer the expansion and contraction of the insulating oil.

  In the above description, the high voltage power source, the cathode power source, and the stator power source are included in the housing 2, but some or all of these power sources may be disposed outside the housing 2. In that case, a high voltage cable or a cable receptacle for introducing a high voltage into the housing 2 is required.

  The X-ray tube 4 according to the present embodiment includes a cathode 44, a rotating anode (hereinafter abbreviated as an anode) 46, and an envelope 42 that encloses the cathode 44 and the anode 46 in a vacuum-tight manner and supports them in an insulating manner. .

  The cathode 44 of the present embodiment has a beam-like electron for forming each focal point of a micro focal point (micro focus) having a focal dimension of less than 0.1 mm, for example, and a large focal spot having a focal dimension of, for example, more than 0.3 mm. A line (hereinafter also referred to as “electron beam”) is generated, and this electron beam is made to collide with the inclined surface 462a of the disk-shaped target 462 of the anode 46 to generate X-rays having a predetermined wavelength. X-rays are emitted from the opening (not shown) provided in the envelope 42 to the outside of the envelope 42. The detailed structure of the cathode 44 will be described later.

  In this embodiment, the anode 46 is composed of a rotating anode, and includes a disk-shaped target 462, a rotor 464 that supports the target 462, and a rotating shaft that supports the rotor 464 (not shown; included inside the rotor 464). A bearing (not shown, included inside the rotor 464) that rotatably supports the rotating shaft, and a fixing portion (not shown, target 462 of the rotor 464) that fixes the outer ring of the bearing. Connected to the opposite end). As the bearing, a ball bearing, a slide bearing, a fluid bearing, or the like can be used.

  The rotor 464 receives a rotating magnetic field from the stator 6 and generates a rotational driving force.

  The target 462 has an umbrella-shaped disk shape and is usually made of a metal material having a high atomic number and a high melting point such as tungsten or a tungsten alloy. In the case where the heat capacity of the target 462 is large, in order to reduce the weight of the target 462, a portion other than the surface layer of the inclined surface 462a serving as an X-ray generation source is a high melting point, high melting point metal material (such as molybdenum). Or a non-metallic material (such as graphite). The target 462 rotates with the center axis m of the anode 46 as the rotation center axis. When an electron beam from the cathode 44 collides with an inclined surface (also referred to as a focal plane) 462a of the target 462, the colliding portion becomes an X-ray source (focal point), and X-rays are emitted from the focal point. Since the target 462 is rotating, the focal point sequentially rotates and forms a circular orbit as a whole. This circular orbit is called a focal orbit 10 (see FIGS. 6 and 7).

  The envelope 42 includes a large-diameter portion 422 that surrounds the target 462 and the cathode 44 of the anode 46, an anode insulating portion 426 that insulates and supports the anode end 424 of the anode 46, and the like. A portion surrounding the cathode 44 of the large-diameter portion 422 includes a cathode insulating portion that supports and insulates the cathode 44. The large-diameter portion 422 has a cylindrical portion 422a and is made of a metal material having relatively high heat resistance such as stainless steel or copper. A circular opening (not shown) is provided in a portion close to the focal point on the target 462 on the side surface of the cylindrical portion 422a, and a radiation window 43 is attached to this opening. The radiation window 43 is made of beryllium or the like having good X-ray transparency, and is coupled to the opening by welding or brazing via a window frame (not shown). As described above, since the radiation window 43 is dimensionally adjusted so as to be arranged directly or close to the cylindrical side surface of the housing 2, the generated X-rays are transmitted through the radiation window 43 to the housing 2. Radiated to the outside.

  The anode insulating portion 426 has a cylindrical shape with one end expanding in a cone shape, and the opening end portion of the cylindrical portion 422a is connected to the portion expanded in the cone shape. The anode insulating portion 426 is made of an insulating material such as heat resistant glass or ceramic.

  As shown in FIGS. 1 to 4, the back surface of the cathode 44 is supported by a support member 48. The support member 48 has a cylindrical and electrically insulating cathode holder 48a, and the cathode 44 is fixed to a predetermined position inside the envelope 42 via the cathode holder 48a.

  The cathode 44 of this embodiment includes a cathode (electron generation source) that generates thermoelectrons, a focusing system that focuses the generated thermoelectrons to form an electron beam, and an insulating support for the cathode and the focusing system. The support member 48 is provided with a high-voltage lead wire (noted above) for supplying power to both.

  The support member 48 is made of, for example, an insulator such as glass or ceramic, and a high-voltage lead wire for power supply is embedded in the insulator. The support member 48 includes a portion that supports a focusing body 442 as a focusing system and a portion that is connected to the envelope 42. A high voltage on the cathode side and a voltage for heating a cathode heater (not shown) are supplied to the high-voltage lead wire from an external power source (high voltage power source, cathode power source, etc.).

  A focusing body 442 as one of the focusing systems encloses a cathode and a heater for heating the cathode. The focusing body 442 includes a plurality (three in this embodiment) of focusing grooves 443 to 445 having a substantially rectangular cross section that is recessed rearward (upward in FIG. 2) with respect to the anode 46. Each focusing groove 443 to 445 is provided with a cathode for generating and emitting thermoelectrons heated to a high temperature. Examples of the cathode include a coiled filament, an oxide cathode, and an impregnated cathode. In this embodiment, a case where a directly heated coiled filament is used is illustrated. By arranging the filaments 446 to 448 in the focusing grooves 443 to 445, an electron beam generated by the heated filaments 446 to 448 and applied to the anode 46 is applied with a high voltage from a high voltage power source (not shown). The radiation area is controlled.

  A focusing electrode 449 as another focusing body is connected to the anode 46 side of the focusing body 442. As shown in FIG. 5, the focusing electrode 449 has a shape capable of creating an electric field for forming each focal point (large focal point, minute focal point) at a predetermined position on the anode 46. In particular, the focusing electrode 449 is used as an effective one for forming a micro focus used for fluoroscopic imaging.

  Returning to FIGS. The focusing body 442 is made of, for example, pure iron, and the focusing electrode 449 is made of, for example, a heat resistant metal such as stainless steel.

  In the present embodiment, the filaments 446 to 448 are divided into a large focus filament for general imaging and a micro focus filament for fluoroscopic imaging, and are arranged separately. In particular, when the filaments 446 and 448 are used as the large focus filament and the filament 447 is used as the micro focus filament, that is, the micro focus filament 447 is disposed in the center and the large focus filaments 446 and 448 are disposed on both sides thereof. is doing.

  In the present embodiment, it is desirable that the large focus filaments 446 and 448 have a larger number of coil turns and / or a larger coil wire diameter than the micro focus filament 447. .

  Further, the converging grooves 443 and 445 where the filaments 446 and 448 for large focal points are arranged are cut toward the vicinity of the center of the converging body 442 (see FIG. 3).

Next, the operation will be described.
In the X-ray tube apparatus 1 shown in FIGS. 1 to 5, when the stator 6 is driven through the stator power source, the rotor 464 rotates at a predetermined speed in response to the rotating magnetic field from the stator 6. 462 also rotates. In this state, when the electron beam emitted from the cathode 44 collides with the inclined surface (focal plane) 462a of the target 462, X-rays having a predetermined wavelength are output from the colliding portion (focal point). The outputted X-ray is radiated to the outside of the housing 2 through a radiation window 43 provided at a predetermined position of the cylindrical portion 422a of the envelope 42.

  In the present embodiment, the filaments 446 and 448 for large focal points are arranged so as to be symmetric with respect to the filament 447 for minute focal points, so that the center of the focal plane at the minute focal point of the target 462 is large. It is possible to prevent the focal point from being displaced from the center of the focal plane. By providing a plurality of filaments for large focal points, the target 462 can be prevented from being displaced from the center of the focal plane of the large focal point and the focal point of the target 462. The electron beam collides from the plural directions of the cathode 44 toward the target 462. By this, the bias of the focal track 10 for large focus on the target 462 is prevented, and an overlapping region A can be created (see FIG. 6). As shown in FIG. 6, the center point of the region A becomes the center Cb1 of the focal plane of the large focal point, which coincides with the center Cs1 of the focal plane of the minute focal point.

  Further, as shown in FIG. 3, by forming the focusing grooves 443 and 445 so as to be grooved toward the vicinity of the center of the focusing body 442, the center of the focal plane of the target 462 at a large focal point can be further increased. It is possible to prevent a deviation from occurring between the center of the focal plane at the micro focus.

  In the conventional configuration, even when the large-focus filament and the micro-focus filament are provided in the cathode of the X-ray tube apparatus, a single large-focus filament is provided. In such a configuration, the electron beam is emitted only from one direction of the cathode toward the target, and the focal track for large focus is biased. As a result, there was a deviation between the focal plane center Cs2 at the micro focus and the focal plane center Cb2 at the large focus (see FIG. 7).

<< Second Embodiment >>
As shown in FIGS. 1 to 4, unlike the first embodiment exemplifying the case where the large focus filaments 446 and 448 and the micro focus filament 447 are provided in a single focusing body 442, In the embodiment, a case where a plurality of converging bodies are provided on the support member 48 and one of them is used for a large focus and the other is used for a micro focus is illustrated. In all the following embodiments, the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIGS. 8 and 9, the X-ray tube apparatus 1a according to the present embodiment includes a cathode 44a having a structure different from that of the first embodiment. Specifically, the cathode 44a includes a first focusing body 442a and a second focusing body 442b disposed at predetermined positions of the support member 48. The second focusing body 442b is disposed about 90 ° away from the first focusing body 442a with the central axis m of the anode 46 as the center. The arrangement of the two focusing bodies 442a and 442b is not limited to 90 °, and can be determined as appropriate within a range of 30 ° to 150 °, for example.

  Each of the focusing bodies 442a and 442b includes a cathode and a heater for heating the cathode.

  The second focusing body 442b includes a plurality of (two in the present embodiment) focusing grooves 443a and 445a having a substantially rectangular cross section that is recessed rearward (rightward in FIG. 8, deep in FIG. 9) with respect to the anode 46. Yes. In each of the converging grooves 443a and 445a, coiled filaments 446 and 448 used for a large focal point as a cathode are arranged, respectively, as in the first embodiment.

  The first focusing body 442 a includes a focusing groove 444 a having a substantially rectangular cross section recessed backward with respect to the anode 46. In the focusing groove 444a, a coiled filament 445 used for a micro focus as a cathode is arranged, as in the first embodiment.

  A focusing electrode 449a effective for forming a micro focus used for fluoroscopic imaging is connected to the anode 46 side of the first focusing body 442a. The focusing electrode 449 a has a shape capable of generating an electric field for forming a micro focus at a predetermined position on the anode 46.

  Unlike the cathode 44 (see FIGS. 1 to 5) of the first embodiment, the cathode 44a of the present embodiment generates filaments 446 and 448 that generate an electron beam for large focus and an electron beam for micro focus. Since the filament 447 is spaced apart as described above, the large-focus electron beam by the filaments 446 and 448 and the micro-focus electron beam by the filament 447 are separately provided on the target 462. Form the focus of.

  Therefore, in the present embodiment, as shown in FIG. 10, a first opening (not shown) is provided at a predetermined position of the cylindrical portion 422a of the envelope 42, and the opening from the filaments 446, 448 is provided in this opening. A radiation window 43a for outputting X-rays for general imaging (for large focus) generated based on the electron beam is formed. Similarly, a second opening (not shown) different from the first opening is provided at a predetermined position of the cylindrical portion 422a of the envelope 42, and an electron beam from the filament 447 is provided in this opening. A radiation window 43b for outputting X-rays for fluoroscopic imaging (for micro focus) generated on the basis of this is formed. The radiation window 43b is generally formed at a predetermined position on the side surface of the cylindrical portion 422a that is about 90 ° apart from the radiation window 43a with the central axis m of the anode 46 as the center.

  Along with this, the X-ray tube apparatus 1 a includes imaging switching means for switching the type of X-rays emitted to the outside of the housing 2. By this switching means, it is possible to radiate an appropriate X-ray according to the imaging use to the outside of the housing 2.

  As shown in FIGS. 8, 10, and 11, the imaging switching unit of the present embodiment is configured by a casing rotation device 100 installed outside the casing 2, and is centered on the central axis m of the anode 46. It is comprised so that the housing | casing 2 can be rotated. Specifically, the casing rotation device 100 includes, for example, a gear 102 such as a gear, a belt 103, and the like, and transmits a driving force through a rod 106 using a motor 104 as a driving unit, and the casing 2 is connected to a central axis. It is configured to be rotatable around m. Note that the casing rotation device 100 also includes a rotation angle recognition sensor 107 of the casing 2 for enabling the above alignment.

  Information detected by the sensor 107 is sent to a control device (not shown) that controls the driving of the motor 104, where the operation start and stop of the motor 104 are controlled. Specifically, the control by the control device automatically stops the driving of the motor 104 when the housing 2 rotates by a predetermined angle. A marker (not shown) for the sensor 107 to detect the rotation of the housing 2 is attached to the housing 2. This marker is composed of irregularities, a reflecting plate, and the like, and is used for accurately detecting the rotation angle of the housing 2.

  In the X-ray tube apparatus 1a having such a configuration, the same operational effects as those of the first embodiment described above can be achieved. Further, in the cathode 44a, an X-ray source formed by the plurality of electron generation sources (filaments 446, 448) is used for a large focal point so as to enable a large current necessary for general imaging, and the remaining electron generation sources are used. Since the X-ray source formed by the (filament 447) is used for a micro focus, switching between fluoroscopic imaging at the micro focus and other general imaging can enable a large current.

  The case rotating device 100 can be incorporated in the system of the X-ray tube device 1a in addition to the case of being attached in the vicinity of the case 2 as in the present embodiment. Further, instead of the case rotating device 100, a case rotating device (not shown) that rotates the case 2 with a magnetic field generated by a coil (stator) may be used.

<< Third Embodiment >>
As shown in FIGS. 8, 10, and 11, a case rotating device 100 that is installed outside the housing 2 and rotates the housing 2 around the central axis m of the anode 46 is used as the photographing switching means. Unlike the second embodiment that exemplifies the above, in this embodiment, an example in which an X-ray tube rotating device 100a that rotates the X-ray tube 4 in the housing 2 is used as the imaging switching means is illustrated.

  As shown in FIG. 12, the X-ray tube apparatus 1 b according to this embodiment includes an imaging switching unit that switches the type of X-rays emitted to the outside of the housing 2. The imaging switching means of the present embodiment is configured by an X-ray tube rotating device 100a installed inside the housing 2 so that the X-ray tube 4 can be rotated around the central axis m of the anode 46. Configured. Specifically, the X-ray tube rotating apparatus 100a includes, for example, a gear 102a such as a gear, a belt, and the like, and transmits a driving force through a rod 106a using a motor 104a serving as a driving unit. It is configured to be rotatable around the axis m. Note that the X-ray tube rotating device 100a also includes a rotation angle recognition sensor 107a for the X-ray tube 4 for enabling the above alignment.

  Information detected by the sensor 107a is sent to a control device (not shown) that controls the driving of the motor 104a, where the operation start and stop of the motor 104a are controlled. Specifically, the control by the control device automatically stops the driving of the motor 104a when the X-ray tube 4 rotates by a predetermined angle. A marker (not shown) for the sensor 107 a to detect the rotation of the X-ray tube 4 is attached to the X-ray tube 4. This marker is for accurately detecting the rotation angle of the X-ray tube 4. Instead of the X-ray tube rotating device 100a, as shown in FIG. 13, an X-ray tube rotating device 100b that rotates the X-ray tube 4 with a magnetic field generated by the stator 6a may be used.

  Returning to FIG. 12, the rotation axis of the X-ray tube 4 is freely rotatable at the anode end 424 of the envelope 42 of the X-ray tube 4 so that the X-ray tube 4 can rotate within the housing 2. A fixing portion 5 is provided for fixing the outer ring of the bearing to be supported. As the bearing, a ball bearing, a slide bearing, a fluid bearing, or the like can be used.

  Also with the X-ray tube apparatus 1b having such a configuration, the same operational effects as those of the above-described embodiment can be obtained.

<< 4th Embodiment >>
As shown in FIGS. 12 and 13, X-ray tube rotating devices 100 a and 100 b that are installed inside the housing 2 and rotate the X-ray tube 4 about the central axis m of the anode 46 are used as imaging switching means. Unlike the third embodiment illustrating the case, in the present embodiment, a case where a cathode rotating device 100c that rotates the cathode 44a in the X-ray tube 4 is used as the imaging switching unit is illustrated.

  As shown in FIG. 14, the X-ray tube apparatus 1 c according to this embodiment includes an imaging switching unit that switches the type of X-rays emitted to the outside of the housing 2. The imaging switching means of the present embodiment is configured by a cathode rotating device 100c that rotates the cathode 44a in the X-ray tube 4 by a magnetic field generated by the stator 6b. The cathode rotating device 100c also includes a rotation angle recognition sensor 107b of the X-ray tube 4 for enabling the above alignment.

  In place of the cathode rotating device 100c, for example, gears such as gears, belts, and the like are provided, and a driving force is transmitted through the rod 106b using a motor as a driving means, and the cathode 44a is rotated about the central axis m. A cathode rotating device (not shown) configured to be possible can also be used. In this case, the information detected by the sensor 107b is sent to a control device (not shown) that controls the driving of the motor, where the operation start and stop of the motor are controlled. Specifically, the control by the control device is configured to automatically stop driving the motor when the cathode 44a rotates by a predetermined angle.

  The X-ray tube apparatus 1c having such a configuration can also provide the same operational effects as those of the above-described embodiment.

  The X-ray tube apparatuses 1, 1a, 1b, and 1c of the above-described embodiments are all mounted and used in an X-ray apparatus that performs examination or diagnosis of a subject. An X-ray apparatus equipped with an X-ray tube apparatus can be used for an X-ray fluoroscopy apparatus, an X-ray imaging apparatus, or the like in the medical field. Further, in the industrial field, it can be used for defect inspection and foreign matter inspection of various products.

  The embodiments described above are described for facilitating the understanding of the invention, and are not described for limiting the invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the above invention.

1, 1a, 1b, 1c ... X-ray tube device 2 ... Housing (X-ray tube container)
DESCRIPTION OF SYMBOLS 22 ... Radiation window 4 ... X-ray tube 42 ... Envelope 422 ... Large diameter part 422a ... Cylindrical part 424 ... Anode end 426 ... Anode insulation part 43 ... Radiation window 44, 44a ... Cathode 442 ... Focusing body (focusing system)
442a ... first focusing body (focusing system)
442b ... second focusing body (focusing system)
443 to 445, 443a to 445a ... focusing groove 446 to 448 ... cathode, filament (electron generation source)
449, 449a ... Focusing electrode (focusing system)
46 ... Anode 462 ... Target 464 ... Rotor 48 ... Support member 5 ... Fixing portions 6, 6a, 6b ... Stator 10 ... Focal orbit 100 ... Case rotating device (imaging switching means)
100a, 100b ... X-ray tube rotating device (imaging switching means)
100c ... Cathode rotating device (photographing switching means)
102, 102a ... gear 103 ... belt 104, 104a ... motor 106, 106a, 106b ... rod 107, 107a, 107b ... rotation angle recognition sensor

Claims (9)

In an X-ray tube apparatus provided with an X-ray tube container including an X-ray tube,
The X-ray tube includes a cathode including three or more electron generation sources that emit electrons, and a focusing system that focuses the electrons emitted from the electron generation sources into a thin beam-shaped electron beam;
An anode having a target disposed opposite to the cathode and forming an X-ray source that radiates X-rays upon collision of the electron beam on the opposing surface;
An envelope for vacuum-tightly sealing the cathode and the anode,
A large-focus X-ray source is formed on the target by two or more electron generation sources, and a micro-focus X-ray source is formed on the target by one or more electron generation sources. An X-ray tube device characterized by comprising. The X-ray tube apparatus according to claim 1,
The focusing system of the cathode comprises a focusing body in which focusing grooves recessed backward with respect to the anode are formed in the same number as the number of the electron generation sources,
A focusing electrode connected to the anode side end of the focusing body;
Among the plurality of focusing grooves, a central cathode has a first cathode for forming a micro focus, and a groove at a symmetrical position across the central groove has a large focal point. The X-ray tube apparatus is characterized in that second cathodes for forming each are disposed. The X-ray tube apparatus according to claim 1, wherein
The focusing system of the cathode includes a first focusing body having a single focusing groove recessed backward with respect to the anode, and a focusing electrode connected to the anode side end of the first focusing body. A second focusing body having a plurality of focusing grooves recessed backward with respect to the anode,
In the single groove formed in the first focusing body, a first cathode for forming a micro focus is disposed, and in the plurality of grooves formed in the second focusing body, An X-ray tube apparatus, wherein a second cathode for forming a large focal point is disposed. The X-ray tube apparatus according to claim 3,
The X-ray tube apparatus, wherein the second focusing body is disposed at a position spaced about 90 ° from the first focusing body with a central axis of the anode as a center. The X-ray tube apparatus according to claim 3 or 4,
At each position of the X-ray tube container facing each focusing body, a radiation window capable of irradiating X-rays radiated from the X-ray source of the target to the outside is provided.
An X-ray tube apparatus comprising imaging switching means capable of switching the type of X-rays irradiated from the radiation window to the outside of the X-ray tube container. The X-ray tube apparatus according to claim 5, wherein
The X-ray tube apparatus characterized in that the imaging switching means comprises an X-ray tube container rotating device capable of rotating the X-ray tube container about a central axis of the anode. The X-ray tube apparatus according to claim 5, wherein
The X-ray tube apparatus characterized in that the imaging switching means is configured by an X-ray tube rotating device capable of rotating the X-ray tube around a central axis of the anode. The X-ray tube apparatus according to claim 5, wherein
The X-ray tube apparatus characterized in that the imaging switching means comprises a cathode rotating device capable of rotating the cathode in the X-ray tube around the central axis of the anode.   An X-ray apparatus equipped with the X-ray tube apparatus according to claim 1.

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