X-ray generator and X-ray imaging system

Abstract

An X-ray generation device according to the present invention comprises: a housing container; an insulating container which comprises a main container body and a lid body and which is housed in the housing container; an X-ray tube which is housed in the insulating container and which generates X-rays through the impingement of electrons; and a plurality of electrical components housed in the insulating container, wherein the lid body covers at least a portion of the main container body, a first space in which at least the X-ray tube is disposed, a second space between the main container body and the lid body, and a third space between the insulating container and the housing container are formed, the second space is connected to each of the first space and the third space, and at least one of the plurality of electrical components is disposed in the second space.

Description

Technical Field

[0001] The present invention relates to an X-ray generating apparatus and an X-ray imaging system.

Background Art

[0002] As one of industrial non-destructive inspection apparatuses, an X-ray imaging system is known. For example, for the inspection of electronic devices typified by semiconductor integrated circuit boards, an X-ray generating apparatus equipped with a microfocus X-ray tube is used. The X-ray tube is an X-ray source that applies a high voltage of a predetermined potential difference corresponding to X-ray energy between an anode and a cathode, and emits X-rays from a target by irradiating the target with electrons accelerated by this high voltage. In such an X-ray source, since a plurality of high-voltage members are used, an abnormal discharge problem may occur between a storage container having a different voltage and the high-voltage members. In Patent Document 1, a lid body using a fitting structure is described in order to suppress abnormal discharge at the joint of an insulating container that houses a high-voltage member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, improvement of the insulation performance between a plurality of high-voltage members arranged in the insulating container was not considered. For this reason, there was a risk that abnormal discharge in the insulating container could not be sufficiently suppressed.

[0005] An object of the present invention is to provide an X-ray generating apparatus and an X-ray imaging system capable of improving the insulation performance between a plurality of high-voltage members arranged in an insulating container.

Means for Solving the Problems

[0006] According to one aspect of the present invention, an X-ray generator is provided, comprising a storage container, an insulating container comprising a container body and a lid and housed in the storage container, an X-ray tube housed in the insulating container that generates X-rays by electron collision, and a plurality of electrical components housed in the insulating container, wherein the lid covers at least a part of the container body and forms a first space in which at least the X-ray tube is arranged, a second space between the container body and the lid, and a third space between the insulating container and the storage container, the second space communicating with the first space and the third space, and at least one of the plurality of electrical components being located in the second space. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an X-ray generator and an X-ray imaging system that can improve the insulation performance between multiple high-voltage components arranged in an insulating container. [Brief explanation of the drawing]

[0008] [Figure 1] This is a block diagram showing the schematic configuration of an X-ray generator according to the first embodiment of the present invention. [Figure 2] This diagram schematically shows the inside of the housing container for an X-ray generator according to the first embodiment of the present invention. [Figure 3] Figure 2 shows a cross-sectional view along the line I-I'. [Figure 4] This figure schematically shows the inside of the housing container for an X-ray generator according to a second embodiment of the present invention. [Figure 5] Figure 4 shows a cross-sectional view along the line II-II'. [Figure 6] This figure schematically shows the inside of the housing container for an X-ray generator according to a third embodiment of the present invention. [Figure 7] Figure 6 shows a cross-sectional view along the line III-III'. [Figure 8]This figure schematically shows the inside of the housing container for an X-ray generator according to the fourth embodiment of the present invention. [Figure 9] Figure 8 shows a cross-sectional view along the line IV-IV'. [Figure 10] This is a block diagram showing the schematic configuration of an X-ray imaging system according to a fifth embodiment of the present invention. [Modes for carrying out the invention]

[0009] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, the same or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0010] [First Embodiment] Figure 1 is a block diagram showing the schematic configuration of an X-ray generator 100 according to a first embodiment of the present invention. As shown in Figure 1, the X-ray generator 100 according to this embodiment includes an X-ray tube 20, a high-voltage generation circuit 30, an electron gun drive circuit 40, and a control unit 50. Of these, at least the X-ray tube 20, the high-voltage generation circuit 30, and the electron gun drive circuit 40 are arranged in a housing container 10. The housing container 10 is filled with insulating oil 80 to ensure the dielectric strength between the parts arranged inside. As the insulating oil 80, an electrical insulating oil such as mineral oil, silicone oil, or fluorine-based oil is preferred. For an X-ray generator using an X-ray tube 20 with a rated tube voltage of about 100kV, mineral oil, which is easy to handle, is preferably used.

[0011] The X-ray tube 20 includes an electron source 22, a grid electrode 26, and an anode 28. The electron source 22 and the grid electrode 26 are connected to an electron gun drive circuit 40, to which a desired control voltage is applied. The anode 28 is connected to a housing 10 held at ground potential. The anode 28 is provided with a target (not shown) that generates X-rays when irradiated with an electron beam. Although only one grid electrode 26 is shown in Figure 1, typically multiple grid electrodes 26 are provided.

[0012] The electron source 22 is not particularly limited, but for example, a hot cathode such as a tungsten filament or an impregnated cathode, or a cold cathode such as a carbon nanotube can be used. The material constituting the target is preferably a material with a high melting point and high X-ray generation efficiency, and for example, tungsten, tantalum, molybdenum and their alloys can be used. In this specification, the electron source 22 and the grid electrode 26 may be collectively referred to as the "electron gun".

[0013] Electrons emitted from the electron source 22 are accelerated by a high voltage between it and the anode 28 and collide with a target provided on the anode 28, causing the target to emit X-rays. The amount of X-rays emitted from the target can be controlled by the electron dose irradiated onto the target, that is, by the supplied current in the case of a hot cathode type electron source 22. The trajectory of the electron beam irradiating the target can be controlled by the grid voltage applied to the grid electrode 26. In this sense, the electron source 22 and the grid electrode 26 are control mechanisms that control the electron beam emitted from the electron gun.

[0014] The high-voltage generation circuit 30 includes a step-up transformer 32 and a step-up circuit 34. The step-up circuit 34 is, for example, a Cockcroft-Walton circuit. The high-voltage generation circuit 30 generates a negative high voltage relative to the housing container 10, which is held at ground potential. The high-voltage generation circuit 30 is connected to the electron gun drive circuit 40. The negative high voltage generated by the high-voltage generation circuit 30 is applied to the electron gun drive circuit 40. This voltage is supplied to the electron source 22 and grid electrode 26 of the X-ray tube 20.

[0015] The electron gun drive circuit 40 includes a rectifier circuit 42, a logic circuit 44, an electron source drive circuit 46, and a grid voltage control circuit 48. The rectifier circuit 42 is connected to the logic circuit 44, the electron source drive circuit 46, and the grid voltage control circuit 48. Thereby, the voltage supplied to the rectifier circuit 42 via the high insulation transformer 36 is rectified and can be supplied to the logic circuit 44, the electron source drive circuit 46, and the grid voltage control circuit 48. One of the input terminals of the rectifier circuit 42 is connected to the output terminal of the high voltage generation circuit 30. That is, in each circuit of the electron gun drive circuit 40, the negative potential supplied from the high voltage generation circuit 30 becomes the reference potential of the electron gun drive circuit 40.

[0016] The electron source drive circuit 46 controls the voltage or current supplied to the electron source 22 according to a control signal supplied from the control circuit 52 via the logic circuit 44. The grid voltage control circuit 48 controls the grid voltage applied to the grid electrode 26 according to a control signal supplied from the control circuit 52 via the logic circuit 44.

[0017] The control unit 50 includes a control circuit 52 and an inverter circuit 54. The control circuit 52 is connected to the electron gun drive circuit 40 and the inverter circuit 54. The inverter circuit 54 includes an inverter 56 connected to the boost transformer 32 disposed in the storage container 10 and an inverter 58 connected to the high insulation transformer 36 disposed in the storage container 10. The control circuit 52 supplies a predetermined control signal to the electron gun drive circuit 40 and the inverter circuit 54. The inverter circuit 54 controls the inverters 56 and 58 according to the control signal supplied from the control circuit 52 and supplies a predetermined drive voltage to the boost transformer 32 and the high insulation transformer 36. The control circuit 52 monitors the output voltage of the high voltage generation circuit 30 and adjusts the drive voltage of the boost transformer 32 by the control signal supplied to the inverter circuit 54 so that the output voltage of the high voltage generation circuit 30 becomes a predetermined voltage.

[0018] As shown in Figure 1, the control unit 50 and the high-voltage generation circuit 30 are connected, i.e., isolated, via a step-up transformer 32. Similarly, the control unit 50 and the electron gun drive circuit 40 are connected, i.e., isolated, via a high-isolation transformer 36. In one example, the control unit 50 is connected to ground potential. The electron gun drive circuit 40 is connected to the high-voltage generation circuit 30. Therefore, a potential difference equivalent to the negative high voltage generated by the high-voltage generation circuit 30 is generated between the control unit 50 and the electron gun drive circuit 40 via the step-up transformer 32. In other words, an electric field is generated between the control unit 50 and the electron gun drive circuit 40.

[0019] Of the paths governing communication between the control circuit 52 and the electron gun drive circuit 40, at least a portion of the path within the housing container 10 is constructed using optical fiber cables 60 to maintain electrical insulation. This allows the control signals from the control circuit 52, which operates with ground potential as the reference potential, to control the electron source drive circuit 46 and the grid voltage control circuit 48 within the electron gun drive circuit 40, which operate with the negative potential supplied by the high-voltage generation circuit 30 as the reference potential. The optical fiber cables 60 are connected to the control circuit 52 and the logic circuit 44 via photoelectric conversion elements 74. The reference potential is the potential treated as a reference in each circuit.

[0020] Figure 2 is a schematic diagram showing the inside of the housing container 10 of the X-ray generator 100 according to this embodiment. Figure 3 is a cross-sectional view along the line I-I' shown in Figure 2, and shows the X-ray generator 100 shown in Figure 2 as viewed from the position along the line I-I' in the positive Z-axis direction.

[0021] The storage container 10 may be made of a conductive material. The storage container 10 houses the insulating container 110. The inside of the storage container 10 is filled with insulating oil 80.

[0022] The insulating container 110 may be formed from a solid insulating material. Preferably, the material of the insulating container 110 is a resin-impregnated glass cloth laminate (e.g., a laminated board, a laminated tube) that has been heat-pressurized. The resin-impregnated glass cloth laminate can be formed, for example, by laminating a member (prepreg) impregnated with a resin such as epoxy resin or phenolic resin onto a glass nonwoven fabric, or by winding a member (prepreg) onto a glass nonwoven fabric and then heat-pressurizing it. Glass epoxy is an example of a material for the insulating container 110.

[0023] In this embodiment, the X-ray generator 100 employs two methods as insulating means: an insulating oil method and a solid insulation method using resin or the like. Generally, the solid insulation method using resin or the like has higher insulating capacity than the insulating oil method. In this embodiment, the invention will be explained using a sealed X-ray generator 100, but the present invention is not limited to sealed types and can also be applied to open types.

[0024] Furthermore, the insulating container 110 may be placed between the inner wall surface of the storage container 10 and at least a portion of the X-ray tube 20. In Figure 2, the insulating container 110 houses the entire X-ray tube 20. The insulating container 110 consists of a container body 120 and a lid 130.

[0025] The container body 120 includes a first insulating member 122, a second insulating member 124, and a ceiling portion 126. The first insulating member 122 and the second insulating member 124 constitute the side walls of the container body 120. Figure 3 shows that the first insulating member 122 is composed of three plates. The first insulating member 122 may be composed of multiple plates as shown in Figure 3, or it may be composed of a single plate.

[0026] Furthermore, as shown in Figure 2, the container body 120 has a bottomed box-shaped recess formed by a part of the ceiling portion 126, the first insulating member 122, and the second insulating member 124. The ceiling portion 126 of the container body 120 has a portion that extends in the positive Y-axis direction from the side wall portion of the recess. In this embodiment, the extension region of the ceiling portion 126 from the side wall portion of the recess is called the extension portion.

[0027] Furthermore, as shown in Figure 2, the recess of the container body 120 has a first opening OP1 that opens in the negative Z-axis direction. On the other hand, the lid 130 has a second opening OP2 that opens in the positive Z-axis direction.

[0028] The container body 120 has at least five surfaces, including the inner wall surface of the first insulating member 122 and the inner wall surface of the second insulating member 124. For example, in Figures 2 and 3, the container body 120 has five surfaces: the inner wall surfaces 122a to 122c of the first insulating member 122, the inner wall surface 124a of the second insulating member 124, and the inner wall surface 126a of the ceiling portion 126.

[0029] One possible method for manufacturing the container body 120 is to join and fill the gaps between adjacent edges of each glass epoxy plate constituting the container body 120 with adhesive. With this configuration, the discharge pressure resistance of the container body 120 can be met by combining the discharge pressure resistance of the glass epoxy plate itself and the discharge pressure resistance of the adhesive embedded in the gaps. When using glass epoxy plates, it is desirable to use epoxy adhesive.

[0030] The lid 130 is constructed in the shape of a bottomed box and includes a bottom portion 132 and side wall portions 134. Figure 3 shows that the side wall portions 134 are composed of four plates. The lid 130 has at least five surfaces, including the walls of the bottom portion 132 and the side wall portions 134. The lid 130 may be configured to cover at least a portion of the container body 120. In this embodiment, the lid 130 is positioned to cover at least the first opening OP1 of the container body 120. The lid 130 is preferably constructed in the same way as the container body 120, by joining multiple glass epoxy plates with epoxy resin adhesive.

[0031] In this embodiment, the internal space enclosed by the recess of the container body 120 and the lid 130 is referred to as the "first space SP1". The first space SP1 is a space enclosed by six surfaces: the inner wall surfaces 122a to 122c of the first insulating member 122 (container body 120), the inner wall surface 124a of the second insulating member 124 (container body 120), the inner wall surface 126a of the ceiling portion 126 (container body 120), and the inner wall surface 132a of the bottom portion 132 (lid 130).

[0032] In this embodiment, the first space SP1 can be formed when the inner wall surface 126a of the top portion 126 (container body 120) and the inner wall surface 132a of the bottom portion 132 (lid 130) face each other, and the lid 130 covers at least the first opening OP1 of the container body 120. At least a portion of the area of ​​the container body 120 located outside the first space SP1 in the positive Y-axis direction can be covered by the lid 130.

[0033] In this embodiment, the internal space enclosed by the inner wall surfaces 122d to 122e of the first insulating member 122 of the container body 120, the outer wall surface 124b of the second insulating member 124, the inner wall surface 126b of the ceiling portion 126, the inner wall surface (bottom surface) 132a of the bottom portion 132 of the lid 130, and the inner wall surface 134b of the side wall portion 134 is called the "second space SP2". The second space SP2 is located outside the first space SP1 in the container body 120. In Figures 2 and 3, the second space SP2 is located in the positive Y-axis direction relative to the first space SP1.

[0034] The second space SP2 is formed when the lid 130 covers the container body 120, with the top portion 126 of the container body 120 and the bottom portion 132 of the lid 130 facing each other. In Figure 3, the first insulating member 122 is formed to extend in the positive Y-axis direction beyond the second insulating member 124 (side wall portion of the recess), similar to the top portion 126, but the position of the second insulating member 124 may be considered the end point. In this case, the second space SP2 may be a space enclosed by the outer wall surface 124b of the second insulating member 124, the inner wall surface 132a of the bottom portion 132 of the lid 130, and the inner wall surfaces 134b to 134d of the side wall portion 134.

[0035] The second space SP2 is in communication with the first space SP1 through the gap between the tip surface 124t of the second insulating member 124 and the inner wall surface 132a of the lid 130 (bottom portion 132) (hereinafter referred to as "first gap Gap1"). In this embodiment, the space formed between the insulating container 110 and the storage container 10, and the outer peripheral space of the insulating container 110, is referred to as "third space SP3". The third space SP3 is in communication with the second space SP2 through the gap between the surface 126b of the extension portion of the container body 120 and the tip surface 134t of the lid 130 (side wall portion 134) (hereinafter referred to as "second gap Gap2").

[0036] It is preferable that the first gap Gap1 and the second gap Gap2 are formed such that the distance in the second space SP2 is maximized. This makes it possible to extend the distance of the electrical path from the electrical components placed in the first space SP1 and the second space SP2 to the ground potential member such as the storage container 10, i.e., the distance in the oil.

[0037] The structures of the first gap Gap1 and the second gap Gap2 can be arbitrarily changed. For example, the first gap Gap1 may be structured such that the entire portion of the second insulating member 124 facing the cover 130 does not come into contact with the cover 130. Alternatively, the first gap Gap1 may be structured such that some or more portions of the second insulating member 124 facing the cover 130 do not come into contact with the cover 130.

[0038] Similarly, the second gap 2 may be structured such that the entire portion of the side wall portion 134 of the lid 130 that faces the ceiling portion 126 does not come into contact with the ceiling portion 126 of the container body 120. Alternatively, the second gap 2 may be structured such that some or more portions of the portion facing the ceiling portion 126 do not come into contact with the ceiling portion 126 of the container body 120. For example, the first gap 1 and the second gap 2 may also be formed as one or more communication holes for passing a cable 16 or an optical fiber cable 60.

[0039] The first space SP1 houses the electron gun side of the X-ray tube 20 and some of the electrical components. Examples of electrical components include an electrical substrate that operates at a high potential (e.g., an electron gun drive circuit 40), a cable 16, an optical fiber cable 60, and a high isolation transformer 36. It is desirable that electrical components such as a circuit that operates at approximately the same potential as the anode 28 (e.g., an electron gun drive circuit 40) be placed in the first space SP1, which is surrounded by the recess of the container body 120 and the lid 130.

[0040] Furthermore, the second space SP2 can house electrical components such as substrates that generate an extreme potential difference at both ends (a potential difference similar to the potential difference between the anode 28 and cathode (electron source 22) of the X-ray tube 20) when electrically driven. Examples of electrical components that can be housed in the second space SP2 include a boost circuit 34 and a high-isolation transformer 36.

[0041] In Figure 2, the boost circuit 34 is housed in the second space SP2. The boost circuit 34 may have a potential in the Z direction (the direction of electrons emitted from the cathode (electron source 22) to the anode 28) that corresponds to the potential difference between the cathode (electron source 22) and the anode 28 in the X-ray tube 20. In this way, the second space SP2 can house the entirety of the desired electrical components. For example, the entire boost circuit 34 is contained within the second space SP2.

[0042] In Figure 2, only the boost circuit 34 is housed in the second space SP2. However, other electrical components that generate an extreme potential difference (a potential difference similar to that between the anode and cathode in the X-ray tube 20) at both ends of the substrate, etc., when electrically driven may be housed in the second space SP2. Furthermore, some of these other electrical components may be housed in the third space SP3.

[0043] The boost circuit 34 housed in the second space SP2 can have the boost circuit high-voltage section on the first gap Gap1 side and the boost circuit ground section on the second gap Gap2 side. The boost circuit high-voltage section is connected to the electron gun drive circuit 40 via cable 16. Therefore, a negative high voltage can be applied to the boost circuit high-voltage section. On the other hand, the boost circuit ground section can be connected via cable 16 to a member having a ground potential (hereinafter referred to as the "ground potential member"). In this embodiment, the ground potential member may be, for example, the housing container 10, the insulating container 110, the control unit 50, etc.

[0044] With this configuration, the side wall portion 134 of the lid 130 can be inserted between the first insulating member 122 and the storage container 10, and between the second insulating member 124 and the storage container 10, thereby creating a second space SP2 outside the first space SP1 where the container body 120 and the lid 130 overlap.

[0045] By providing this overlapping portion (second space SP2), the oil-immersion withstand voltage distance (hereinafter referred to as "oil-immersion distance") between the electron gun drive circuit 40, which is driven by a high voltage within the first space SP1, and the storage container 10, which is at ground potential, can be extended, thereby reducing the probability of discharge.

[0046] Furthermore, the third space SP3 is the space located between the insulating container 110 and the storage container 10, and is the outer periphery space of the insulating container 110. A second space SP2 exists between the first space SP1 and the third space SP3. Therefore, even if an electrical circuit (for example, an electron gun drive circuit 40) that is driven under a high voltage state is placed in the first space SP1, the presence of the second space SP2 allows the distance between the storage container 10, which is at ground potential as described above, to be extended. This prevents abnormal discharge caused by the potential difference between the electrical circuit such as the electron gun drive circuit 40 and the storage container 10.

[0047] Furthermore, by placing the boost circuit 34 in the second space SP2, the oil-submerged distance between the electron gun drive circuit 40 and the boost circuit ground of the boost circuit 34 can be extended. This prevents abnormal discharge caused by the potential difference between the electron gun drive circuit 40 and the boost circuit ground.

[0048] Furthermore, by placing the boost circuit 34 in the second space SP2, the distance between the high-voltage section of the boost circuit 34 and the ground potential member such as the housing container 10 can be extended. This also prevents abnormal discharge between the high-voltage section of the boost circuit 34 and the ground potential member.

[0049] Furthermore, the optical fiber cable 60 has a potential difference between the region near the photoelectric conversion element 74a located on the electron gun drive circuit 40 side, which is under high voltage, and the region near the photoelectric conversion element 74b located on the storage container 10 side, which is under ground potential. For this reason, as shown in Figure 2, the high-voltage side photoelectric conversion element 74a is located near the first gap Gap1 in the first space SP1, and the ground side photoelectric conversion element 74b is located near the second gap Gap2 in the third space SP3.

[0050] This arrangement prevents abnormal discharge due to the potential difference between the vicinity of the high-voltage side photoelectric conversion element 74a and the vicinity of the ground side photoelectric conversion element 74b. In other words, abnormal discharge can be prevented by extending the oil-covered distance between the vicinity of the photoelectric conversion element 74a and the vicinity of the photoelectric conversion element 74b. Similarly, abnormal discharge can be prevented by extending the oil-covered distance between the vicinity of the high-voltage side photoelectric conversion element 74a and the ground potential member such as the housing container 10.

[0051] Furthermore, in conventional X-ray generators, increasing the operating voltage necessitated a larger insulating container to ensure insulation within the insulating container housing the high-voltage components. This could lead to increased manufacturing costs and reduced design flexibility when attaching the insulating container to the X-ray generator. In contrast, the present invention, by adopting the structure shown in Figures 2 and 3, can improve insulation performance between multiple high-voltage components (e.g., electron gun drive circuit 40, boost circuit 34, optical fiber cable 60, etc.) arranged within the insulating container 110, while suppressing increases in manufacturing costs and the enlargement of the insulating container 110.

[0052] Furthermore, a first gap communicating with the first space SP1 is provided at one end of the second space SP2, and a second gap communicating with the third space is provided at the other end. By not sealing the second space SP2 in this way, it becomes possible to cool the first space SP1, the second space SP2, and the components housed in each space. Moreover, by not sealing the second space SP2, it is also possible to prevent abnormal discharge due to static charge buildup of the insulating oil 80 in the second space SP2.

[0053] In this embodiment, the X-ray generator 100 employs two methods of insulation: an insulating oil method and a solid insulation method. However, it is also possible to employ only the solid insulation method. That is, there may be a device configuration in which the housing container 10 is not filled with insulating oil 80. Even when the housing container 10 is not filled with insulating oil 80, a second space SP2 is provided within the insulating container 110 that communicates with the first space SP1 and the third space SP3 (the outer periphery space of the insulating container 110), and electrical components such as the boost circuit 34 are placed in the second space SP2. This increases the distance of the electrical paths between electrical components within the insulating container 110. This improves the insulation performance within the insulating container 110 while suppressing increases in manufacturing costs and the size of the insulating container 110.

[0054] Furthermore, in this embodiment, the X-ray generator 100 has a second space SP2 formed by being surrounded by two surfaces of the container body 120 and four surfaces of the lid 130, but the combination of surfaces forming the second space SP2 is not limited to this. That is, the second space SP2 can be formed by being surrounded by at least one surface of one of the container body 120 and the lid 130 and the surface of the other member when the container body 120 and the lid 130 are fitted together.

[0055] [Second Embodiment] The following describes an X-ray generator according to the second embodiment. The second embodiment is a modification of the first embodiment. Reference numerals that are the same as those used in the figures of the first embodiment indicate the same objects. The explanation of parts that are common with the first embodiment will be omitted, and the differences will be explained in detail.

[0056] Figure 4 is a schematic diagram showing the inside of the housing container 10 of the X-ray generator 100 according to this embodiment. Figure 5 is a cross-sectional view along the line II-II' shown in Figure 4, and shows the X-ray generator 100 shown in Figure 4 as viewed in the positive Z-axis direction from the position along the line II-II'.

[0057] As shown in Figures 4 and 5, the X-ray generator 100 according to this embodiment differs from the first embodiment in that it includes a relay circuit 19 in the second space SP2, the container body 120 further comprises a third insulating member 128, a third opening OP3 is formed between the first insulating member 122, the second insulating member 124, and the third insulating member 128, and the side wall portion 134 of the lid 130 is inserted into the third opening OP3, and the bottom portion 132 of the lid 130 is positioned to cover a part of the third opening OP3 in a plan view (XY plane viewed in the Z-axis direction).

[0058] The relay circuit 19 is a circuit driven by a voltage close to ground potential. Therefore, even if the relay circuit 19 is placed in the third space SP3 adjacent to the housing container 10 which has ground potential, there is a low possibility of inducing discharge. The relay circuit 19 may also be connected to a connector (not shown) of the housing container 10. The relay circuit 19 may include electrical components such as a photoelectric conversion element 74b.

[0059] Furthermore, as shown in Figures 4 and 5, the lid 130 is composed of one bottom portion 132 and four side wall portions 134. In the Z-axis direction, the lid 130 covers the three first insulating members 122 and second insulating members 124 of the container body 120. The first space SP1 in this embodiment is formed by six surfaces, similar to the first embodiment: the inner wall surfaces 122a to 122c of the first insulating member 122 (container body 120), the inner wall surface 124a of the second insulating member 124, the inner wall surface 126a of the ceiling portion 126, and the inner wall surface 132a of the bottom portion 132 (lid 130).

[0060] Furthermore, the second space SP2 in this embodiment is formed by six surfaces: the surface 126b of the extension portion of the container body 120, the outer wall surface 124b of the second insulating member 124, the inner wall surface 132a of the bottom portion 132 of the lid 130, and the inner wall surface 134b of the side wall portion 134. In Figure 5, the first insulating member 122 is formed to extend in the positive Y-axis direction beyond the second insulating member 124 (side wall portion of the recess), similar to the ceiling portion 126, but the position of the second insulating member 124 may be considered the end point. Alternatively, in Figure 5, the first insulating member 122 is formed to extend in the positive Y-axis direction beyond the side wall portion 134 of the lid 130, similar to the ceiling portion 126, but the position of the side wall portion 134 of the lid 130 may be considered the end point.

[0061] This configuration allows the side wall portion 134 of the insulating lid 130 to be inserted between the second insulating member 124 and the storage container 10, and also creates a portion (second space SP2) where the container body 120 and the lid 130 overlap outside the first space SP1.

[0062] This overlapping portion (second space SP2) allows for an extension of the oil-submerged distance between the boost circuit 34 and the storage container 10, which is at ground potential, thereby reducing the probability of discharge. Therefore, even if an electrical circuit with a high voltage overall (for example, the boost circuit 34) is placed in the second space SP2, the oil-submerged distance to the storage container 10, which is at ground potential, can be extended as described above. Furthermore, by inserting the side wall portion 134 of the lid 130 into the third opening OP3, the oil-submerged distance between the electrical components and the ground potential member can be further extended.

[0063] Furthermore, by adopting a configuration like that of the second embodiment, the distance between electrical components in the oil and the distance between electrical components and the storage container 10 in the oil can be extended. This makes it possible to improve the insulation performance between multiple high-voltage components arranged inside the insulating container 110 while suppressing an increase in the size of the insulating container 110, thereby preventing abnormal discharge (discharge in oil).

[0064] [Third Embodiment] The following describes an X-ray generator according to the third embodiment. The third embodiment is a modification of the first embodiment. Reference numerals that are the same as those used in the figures of the first embodiment indicate the same objects. The explanation of parts that are common with the first embodiment will be omitted, and the differences will be explained in detail.

[0065] Figure 6 is a schematic diagram showing the inside of the housing container 10 of the X-ray generator 100 according to this embodiment. Figure 7 is a cross-sectional view along the line III-III' shown in Figure 6, and shows the X-ray generator 100 shown in Figure 6 as viewed from the position along the line III-III' in the positive Z-axis direction.

[0066] As shown in Figures 6 and 7, the X-ray generator 100 according to this embodiment differs from the first embodiment in that the high-isolation transformer 36 is located in the second space SP2 instead of the first space SP1.

[0067] As shown in Figure 6, when the high isolation transformer 36 is placed in the second space SP2, the high isolation transformer 36 can be configured to have a high-voltage section to which a negative high voltage is applied on the first gap Gap1 side, and a high-ground section to which the second gap Gap2 side is at ground potential.

[0068] In other words, when the high-isolation transformer 36 is placed in the second space SP2, the high-isolation transformer ground section, which is the primary wiring of the high-isolation transformer 36, may be placed in a location that is close to the storage container 10 in the oil. Conversely, the high-isolation transformer ground section may be placed in a location that is far from the electron gun drive circuit 40 in the oil. On the other hand, the high-isolation transformer high-voltage section, which is the secondary wiring of the high-isolation transformer 36, may be placed in a location that is far from the storage container 10 in the oil.

[0069] This arrangement prevents abnormal discharge caused by the potential difference between the electron gun drive circuit 40 and the high-isolation transformer ground section. In other words, abnormal discharge can be prevented by extending the oil-covered distance between the electron gun drive circuit 40 and the high-isolation transformer ground section. Similarly, abnormal discharge can be prevented by extending the oil-covered distance between the high-voltage section of the high-isolation transformer and a ground potential member such as the housing container 10.

[0070] [Fourth Embodiment] The following describes an X-ray generator according to the fourth embodiment. The fourth embodiment is a modification of the first embodiment. Reference numerals that are the same as those used in the figures of the first embodiment indicate the same objects. The explanation of parts that are common with the first embodiment will be omitted, and the differences will be explained in detail.

[0071] Figure 8 is a schematic diagram showing the inside of the housing of the X-ray generator according to this embodiment. Figure 9 is a cross-sectional view along the IV-IV' line shown in Figure 8, and shows the X-ray generator 100 shown in Figure 7 viewed from the position along the IV-IV' line in the positive Z-axis direction.

[0072] As shown in Figures 8 and 9, the X-ray generator 100 according to this embodiment differs from the first embodiment in terms of the combination of surfaces forming the first space SP1 and the second space SP2.

[0073] In this embodiment, the first space SP1 is formed by being surrounded by six surfaces: the inner wall surface 124a of the second insulating member 124 of the container body 120, the inner wall surface 126a of the ceiling portion 126, the inner wall surface 132a of the bottom portion 132 of the lid 130, and the inner wall surfaces 134a, 134c, and 134d of the side wall portion 134. It is assumed that a space is formed between the first insulating member 122 and the second insulating member 124 into which the side wall portion 134 of the lid 130 can be inserted in the Z-axis direction.

[0074] In this embodiment, unlike the first embodiment, the side wall portion 134 of the lid 130 is positioned inside the first insulating member 122 of the container body 120, so that the first insulating member 122 does not come into contact with the first space SP1. In Figure 9, it can be seen that in the XY plane, the container body 120 (first insulating member 122) covers the side wall portion 134 of the lid 130 from the outside. In this case as well, the first insulating member 122 is positioned between the side wall portion 134 and the storage container 10, so that an overlapping portion (second space SP2) can be formed outside the first space SP1 where the container body 120 and the lid 130 overlap.

[0075] By adopting the configuration described in this embodiment, it is possible to improve the insulation performance between multiple high-voltage components arranged within the insulating container 110 while suppressing an increase in the size of the insulating container 110. Furthermore, by not sealing the second space SP2, it becomes possible to cool the first space SP1, the second space SP2, and the components housed within each space. Moreover, by not sealing the second space SP2, it is possible to prevent abnormal discharge due to the charging of the insulating oil 80 in the second space SP2.

[0076] [Fifth Embodiment] A fifth embodiment of the present invention, an X-ray imaging system, will be described with reference to Figure 10. Figure 10 is a block diagram showing the schematic configuration of the X-ray imaging system SYS according to this embodiment.

[0077] This embodiment shows an X-ray imaging system SYS using an X-ray generator according to the first to fourth embodiments.

[0078] As shown in Figure 10, the X-ray imaging system SYS according to this embodiment includes an X-ray generator 100, an X-ray detection device 200, a system control device 300, and a display device 400.

[0079] The X-ray generator 100 is an X-ray generator according to any of the first to fourth embodiments and includes an X-ray tube 20 and an X-ray tube drive circuit 102. The X-ray tube drive circuit 102 includes a high-voltage generation circuit 30, an electron gun drive circuit 40, a control unit 50, etc., in the X-ray generator of the first to fourth embodiments. The X-ray detection device 200 includes an X-ray detector 202 and a signal processing unit 204. The system control device 300 controls the entire system, including the X-ray generator 100 and the X-ray detection device 200. The display device 400 displays the image signal processed by the system control device 300 on a screen.

[0080] The X-ray tube drive circuit 102 of the X-ray generator 100 outputs various control signals to the X-ray tube 20 under the control of the system control device 300. The emission state of the X-rays emitted from the X-ray generator 100 is controlled by the control signals output from the system control device 300.

[0081] X-rays (XR) emitted from the X-ray generator 100 pass through the subject (target) TA and are detected by the X-ray detector 202. The X-ray detector 202 is equipped with multiple detection elements (not shown) and acquires a transmitted X-ray image. The X-ray detector 202 converts the acquired transmitted X-ray image into an image signal and outputs it to the signal processing unit 204. A slit, collimator, or the like (not shown) may be placed between the X-ray tube 20 and the subject TA to suppress irradiation of unwanted X-rays.

[0082] The signal processing unit 204, under the control of the system control unit 300, applies predetermined signal processing to the image signal and outputs the processed image signal to the system control unit 300. Based on the processed image signal, the system control unit 300 outputs a display signal to the display device 400 in order to display the image on the display device 400. The display device 400 displays the captured image of the subject TA based on the display signal on the screen.

[0083] Thus, according to this embodiment, by using the X-ray generator 100 according to the first to fourth embodiments, which is compact and has excellent discharge withstand voltage characteristics, a highly reliable X-ray imaging system SYS can be realized that can stably acquire captured images.

[0084] The present invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are attached to make the scope of the invention public. [Explanation of symbols]

[0085] 10 ... Storage containers 16… Cable 19 ... relay circuit 20...X-ray tube 22...electron source 26 ... Grid electrodes 28...anode 30... High-voltage generation circuit 32…Step-up transformer 34 ... Boost circuit 36... High isolation transformer 40 ...Electron gun drive circuit 42... Rectifier circuit 44...Logic circuits 46 ... Electron source drive circuit 48 ...Grid voltage control circuit 50 ... Control Unit 52 ...control circuit 54 ... Inverter circuit 56, 58... Inverter 60… Fiber optic cable 74, 74a, 74b... Photoelectric conversion elements 80 ... Insulating oil 100 ...X-ray generator 102 ...X-ray tube drive circuit 110 ...insulating container 120 ... Container body 122 ...First insulating member 124 ...Second insulating member 126 ... Ceiling 128 ... Third insulating member 130 ... Lid 132…Bottom 134 ... side wall section 200 ...X-ray detection device 202 ...X-ray detector 204 ... Signal Processing Unit 300 ... System control unit 400...display device SYS ...X-ray imaging system Gap1…1st gap Gap2…Second gap Gap3…3rd gap OP1…1st opening OP2 ... Second opening OP3…Third opening SP1…1st space SP2…Second space SP3…Third space TA ... Subject XR ... X-ray

Claims

1. Storage containers and It consists of a container body and a lid, and an insulating container is housed in the storage container, An X-ray tube, housed in the aforementioned insulating container, generates X-rays through electron collisions, Multiple electrical components housed in the aforementioned insulating container, An X-ray generator equipped with, The lid covers at least a part of the container body, At least the first space in which the X-ray tube is arranged, The second space between the container body and the lid, A third space is formed between the insulating container and the storage container. The second space is connected to the first space and the third space, respectively. At least one of the aforementioned plurality of electrical components is located in the second space. Each of the container body and the lid is formed in a concave shape, The container body includes a recess having an opening and an extension extending from a part of the recess in the direction of the outer circumference of the opening. The cover covers at least the opening, The first space is surrounded by the inner wall surface of the recess and the inner wall surface of the lid, The second space is surrounded by the outer wall surface of the recess, the extension, and the inner wall surface of the cover. The container body has a first insulating member, a second insulating member, and a ceiling portion. The first insulating member and the second insulating member constitute the side wall portion of the container body. The recess of the container body is composed of a part of the ceiling portion, the first insulating member, and the second insulating member. The extension portion is an extension region from the side wall portion of the recess of the container body in the ceiling portion, The extension intersects with a virtual plane that includes the inner wall surface of the lid. An X-ray generator characterized by the following features.

2. Storage containers and It consists of a container body and a lid, and an insulating container is housed in the storage container, An X-ray tube, housed in the aforementioned insulating container, generates X-rays through electron collisions, Multiple electrical components housed in the aforementioned insulating container, An X-ray generator equipped with, The lid covers at least a part of the container body, At least the first space in which the X-ray tube is arranged, The second space between the container body and the lid, A third space is formed between the insulating container and the storage container. The second space is connected to the first space and the third space, respectively. At least one of the aforementioned plurality of electrical components is located in the second space. The electrical components arranged in the second space are a Cockcroft-Walton circuit. An X-ray generator characterized by the following features.

3. A first gap is provided between the bottom of the lid and the container body, connecting the first space and the second space. A second gap is provided between the opening end of the recess of the lid and the extension, connecting the second space and the third space. The X-ray generator according to feature 1.

4. The first gap and the second gap are formed such that the distance in the second space is maximized. The X-ray generator according to feature 3.

5. The electrical components arranged in the second space are provided with a ground portion having a ground potential on the side of the second gap and a high-voltage portion having a potential higher than the ground potential on the side of the first gap. The X-ray generator according to claim 3 or 4.

6. Each of the container body and the lid has at least five surfaces, The second space is surrounded by at least one surface of the container body and the lid, and the surface of the other member. The X-ray generator according to any one of claims 1 to 4.

7. The entirety of the electrical components arranged in the second space is included in the second space. The X-ray generator according to any one of claims 1 to 4.

8. The electrical components arranged in the second space have a potential difference between the primary and secondary wiring that corresponds to the potential difference between the cathode and anode of the X-ray tube. The X-ray generator according to any one of claims 1 to 4.

9. The aforementioned storage container is made of a conductive material, The inside of the aforementioned storage container is filled with insulating oil. The X-ray generator according to any one of claims 1 to 4.

10. The electrical components arranged in the second space include at least one of a Cockcroft-Walton circuit, an isolation transformer, and an optical fiber cable. The X-ray generator according to any one of claims 1 to 4.

11. An X-ray generator according to any one of claims 1 to 4, An X-ray detection device for detecting X-rays emitted from the aforementioned X-ray generator and transmitted through the subject, A signal processing unit that converts the transmitted X-ray image of the subject, detected by the X-ray detection device, into an image signal. An X-ray imaging system characterized by having [a certain feature].

12. Storage containers and It consists of a container body and a lid, and an insulating container is housed in the storage container, An X-ray tube, housed in the aforementioned insulating container, generates X-rays through electron collisions, Multiple electrical components housed in the aforementioned insulating container, An X-ray generator equipped with, The lid covers at least a part of the container body, At least the first space in which the X-ray tube is arranged, The second space between the container body and the lid, A third space is formed between the insulating container and the storage container. The second space is connected to the first space and the third space, respectively. At least one of the aforementioned plurality of electrical components is located in the second space. Each of the container body and the lid is formed in a concave shape, The container body includes a recess having a first opening and an extension extending from a part of the recess in the direction of the outer circumference of the first opening. The cover covers at least the first opening, The first space is surrounded by the inner wall surface of the recess and the inner wall surface of the lid, The second space is surrounded by the outer wall surface of the recess, the extension, and the inner wall surface of the cover. The container body has a first insulating member, a second insulating member, and a ceiling portion. The first insulating member and the second insulating member constitute the side wall portion of the container body. The recess of the container body is composed of a part of the ceiling portion, the first insulating member, and the second insulating member. The extension portion is an extension region from the side wall portion of the recess of the container body in the ceiling portion, The container body has a third insulating member, The container body is provided with a second insulating member and a third insulating member. It has two openings, The inner wall surface of the cover is installed inside the second opening. An X-ray generator characterized by the following features.

13. A first gap is provided between the bottom of the lid and the container body, connecting the first space and the second space. A second gap is provided between the opening end of the recess of the lid and the extension, connecting the second space and the third space. The X-ray generator according to claim 12.

14. The first gap and the second gap are formed such that the distance in the second space is maximized. The X-ray generator according to feature 13.

15. The electrical components arranged in the second space are provided with a ground portion having a ground potential on the side of the second gap and a high-voltage portion having a potential higher than the ground potential on the side of the first gap. The X-ray generator according to claim 13 or 14.

16. Each of the container body and the lid has at least five surfaces, The second space is surrounded by at least one surface of the container body and the lid, and the surface of the other member. The X-ray generator according to any one of claims 12 to 14.

17. The entirety of the electrical components arranged in the second space is included in the second space. The X-ray generator according to any one of claims 12 to 14.

18. The electrical components arranged in the second space have a potential difference between the primary and secondary wiring that corresponds to the potential difference between the cathode and anode of the X-ray tube. The X-ray generator according to any one of claims 12 to 14.

19. The aforementioned storage container is made of a conductive material, The inside of the aforementioned storage container is filled with insulating oil. The X-ray generator according to any one of claims 12 to 14.

20. The electrical components arranged in the second space include at least one of a Cockcroft-Walton circuit, an isolation transformer, and an optical fiber cable. The X-ray generator according to any one of claims 12 to 14.

21. An X-ray generator according to any one of claims 12 to 14, An X-ray detection device for detecting X-rays emitted from the aforementioned X-ray generator and transmitted through the subject, A signal processing unit that converts the transmitted X-ray image of the subject, detected by the X-ray detection device, into an image signal. An X-ray imaging system characterized by having [a certain feature].

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