JP7502966B2 - Energy ray tube - Google Patents

Description

The present invention relates to an energy ray tube.

Energy ray tubes that irradiate or receive energy rays are known (for example, Patent Document 1). Patent Document 1 describes a transmission type energy ray tube that emits energy rays. This energy ray tube has a housing and a window provided in the housing. The window allows the energy rays to pass through.

JP 2002-042705 A

In the energy ray tube, the internal space of the housing is sealed. In the energy ray tube, the internal space is maintained in a vacuum state. However, the sealed state of the internal space may be damaged by stress caused by various factors. For example, a heating process is often performed when vacuum sealing. In this heating process, the energy ray tube is heated to a high temperature and then returned to room temperature. At this time, thermal stress caused by the difference in thermal expansion coefficient between the window portion and the housing portion may occur in the fixing portion that fixes the window portion to the housing portion. In this case, the thermal stress may cause distortion in the fixing portion. The occurrence of distortion in the fixing portion may damage the fixing portion, causing the sealing state of the internal space to be damaged. For example, if the sealed state is damaged during manufacturing, production efficiency may decrease.

One aspect of the present invention aims to provide an energy ray tube that can prevent the sealing of the internal space from being damaged.

The energy ray tube according to one embodiment of the present invention comprises a window, a housing, and a joint. The window includes a window that transmits energy rays. The housing has an opening that is covered by the window. The joint fixes the window to the housing. The joint includes a first joint and at least one second joint. The first joint is continuously formed in a frame shape along the edge of the opening, and seals the internal space surrounded by the housing and the window. The at least one second joint is formed along the first joint. A separation portion is disposed between the first joint and the at least one second joint.

In one of the above embodiments, at least one second joint is arranged along the first joint that seals the internal space. A spacer is arranged between the first joint and the at least one second joint. Therefore, the strength of the fixed portion between the housing portion and the window portion is ensured by the at least one second joint. For example, even if damage such as a crack occurs in the second joint, the spacer arranged between the first joint and the second joint makes it difficult for the damage caused in the second joint to affect the first joint. Therefore, the sealing state of the internal space is unlikely to be compromised.

In one of the above embodiments, at least one second joint may be disposed outside the area surrounded by the first joint when viewed from the opening direction of the opening. In this case, the sealing state at the first joint is further prevented from being impaired.

In one of the above embodiments, at least one second joint may be arranged in a continuous frame shape along the edge of the first joint outside the internal space. In this case, the stress applied to the first joint can be uniformly reduced by the second joint arranged in a continuous frame shape. As a result, while the structure is easy to form the first joint and the second joint, the sealing state of the internal space can be further prevented from being damaged.

In one of the above embodiments, at least one second joint may include a plurality of second joints that are arranged along an edge of the first joint and spaced apart from one another. In this case, since the plurality of second joints are spaced apart from one another, damage to the second joints is prevented from occurring continuously over a wide area. In other words, even if damage occurs to one second joint, this damage is unlikely to affect the occurrence of damage in other second joints.

In one of the above embodiments, the joint may further include a connecting portion that connects the first joint and at least one second joint. In this case, a structure that makes it easy to form the first joint, the second joint, and the separation portion is realized.

In one of the above embodiments, the width of at least one second joint may be smaller than the width of the first joint when viewed from the opening direction of the opening. In this case, damage occurs to the second joint before damage occurs to the first joint. Therefore, damage is less likely to occur in the vacuum-sealed first joint, and the sealed state of the internal space can be prevented from being impaired.

In one of the above embodiments, the area of the bonding region of at least one second bonding portion may be smaller than the area of the bonding region of the first bonding portion of the first bonding portion when viewed from the opening direction of the opening. In this case, damage occurs to the second bonding portion before damage occurs to the first bonding portion. Therefore, damage is less likely to occur in the vacuum-sealed first bonding portion, and the sealed state of the internal space can be prevented from being impaired.

In one of the above embodiments, the first joint and at least one of the second joints may be formed by a brazing material. In this case, the internal space can be sealed in a configuration that is easy to manufacture.

In one of the above embodiments, the window portion may include a groove facing the gap. In this case, a structure is realized that makes it easy to form a gap between the first joint portion and the second joint portion.

In one of the above embodiments, the device may further include a frame portion that is provided along the edge of the opening and is fixed to the housing portion by welding. The joint may fix the window portion to the frame portion. In this case, the internal space can be easily sealed.

In one of the above embodiments, the frame portion may include a groove facing the separation portion. In this case, a structure is realized that makes it easy to form the separation portion between the first joint portion and the second joint portion.

In one of the above embodiments, the frame may be fixed to the housing on the outer side of the window when viewed from the opening direction of the opening. In this case, the frame and the housing can be easily welded together.

In one of the above aspects, the housing may include an edge that defines the opening. The window may include an end that faces the edge in the opening direction of the opening. In this case, displacement between the window and the housing is suppressed. Therefore, the sealing state of the internal space is less likely to be compromised.

One aspect of the present invention is to provide an energy ray tube that can prevent the sealing of the internal space from being damaged.

1 is a cross-sectional view showing an energy ray generating device in an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an energy ray tube. FIG. 2 is a diagram showing a portion of an energy ray tube. FIG. 4(a) to 4(c) are schematic diagrams showing the configuration of a joint portion. 4A and 4B are schematic diagrams showing the configuration of a joint portion. 13A and 13B are partial enlarged views of an energy ray tube in a modified example of the present embodiment. 1A to 1C are diagrams showing a manufacturing process of an energy ray tube. 1A to 1C are diagrams showing a manufacturing process of an energy ray tube. 1 is a diagram for explaining a stress applied to an energy ray tube. FIG.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings. In the description, the same elements or elements having the same functions will be designated by the same reference numerals, and duplicate descriptions will be omitted.

First, the configuration of the energy ray tube in this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic diagram showing the configuration of an energy ray generating device in this embodiment. Figure 2 is a vertical cross-sectional view of the energy ray tube in this embodiment. As shown in Figures 1 and 2, the energy ray generating device 100 is, for example, an X-ray generating device that irradiates X-rays. The X-axis direction, Y-axis direction, and Z-axis direction are mutually orthogonal. In this embodiment, X-rays are irradiated in the Z-axis direction. The energy ray generating device 100 includes a device housing 1, a power supply unit 2, and an energy ray tube 3.

The device housing 1 comprises a tubular member 10 and a power supply case 20. The tubular member 10 is made of metal. The tubular member 10 has a cylindrical shape with an opening 10a formed at one end and an opening 10b formed at the other end. A part of the energy ray tube 3 is inserted into the opening 10a of the tubular member 10.

The mounting flange 3a of the energy ray tube 3 is abutted against one end of the cylindrical member 10 and fixed with screws or the like. The energy ray tube 3 is fixed to the opening 10a of the cylindrical member 10, sealing the opening 10a. Inside the cylindrical member 10, insulating oil 11, which is a liquid electrical insulating material, is sealed.

The power supply unit 2 supplies power to the energy ray tube 3. In addition to the power supply unit case 20 described above, the power supply unit 2 has an insulating block 21, a boost circuit 22, and a control board 23. The power supply unit case 20 houses the insulating block 21, the boost circuit 22, and the control board 23. The insulating block 21 is made of a molded solid insulating material, for example, epoxy resin, which is an insulating resin. The boost circuit 22 is molded in the insulating block 21. The boost circuit 22 generates a high voltage V. The insulating block 21 seals the boost circuit 22 with an insulating material. The control board 23 controls the operation of the energy ray generator 100. The control board 23 performs control related to the generation of energy rays. The control board 23 controls, for example, the voltage or current supplied to the energy ray tube 3 and the drive of the boost circuit 22. The control board 23 has an internal board 23a molded in the insulating block 21 and an external board 23b arranged outside the insulating block 21.

The other end of the tubular member 10 is fixed to the power supply unit 2. This seals the opening 10b of the tubular member 10, and the insulating oil 11 is hermetically sealed inside the tubular member 10. The opening 10b is located on the opposite side to the opening 10a.

The energy ray generating device 100 further includes a high-voltage power supply unit 4. The high-voltage power supply unit 4 is disposed on an insulating block 21. The high-voltage power supply unit 4 includes a cylindrical socket electrically connected to a boost circuit 22 and a control board 23. The energy ray tube 3 is electrically connected to the power supply unit 2 via the high-voltage power supply unit 4. At the same time, the high-voltage power supply unit 4 is fixed to the insulating block 21 while being electrically connected to the boost circuit 22 and the control board 23.

The energy ray tube 3 is an X-ray tube that irradiates X-rays generated in the internal space R described later to the outside. The energy ray tube 3 includes an insulating bulb 6 and a head portion 7. The insulating bulb 6 is formed of an insulating material. Examples of insulating materials include glass and ceramics. The insulating bulb 6 is made of, for example, glass or ceramics. The insulating bulb 6 is inserted into a cylindrical member 10. The head portion 7 includes a metal. Examples of metal materials include stainless steel and Kovar. The head portion 7 is made of, for example, stainless steel or Kovar. The insulating bulb 6 and the head portion 7 form an internal space R. The internal space R is sealed to be a vacuum space. The energy ray tube 3 further includes an electron gun 110 in the internal space R. The electron gun 110 corresponds to the cathode of the energy ray tube 3 in terms of potential, and generates and emits an electron beam B.

The electron gun 110 is fixed to the insulating valve 6. The insulating valve 6 has a cylindrical shape extending along the tube axis of the energy ray tube 3. The insulating valve 6 has a bottom 6a facing the head portion 7. The bottom 6a is provided with a stem pin S used for power supply to the electron gun 110. The stem pin S penetrates the bottom 6a and supports the electron gun 110 at a predetermined position in the internal space R. The stem pin S protrudes from the bottom 6a of the insulating valve 6 of the energy ray tube 3 to the outside of the internal space R and is electrically connected to the high-voltage power supply unit 4.

The electron gun 110 has a heater 111, a cathode 112, a first grid electrode 113, and a second grid electrode 114. The heater 111 is formed of a filament that generates heat when electricity is applied. The cathode 112 emits electrons when heated by the heater 111. The first grid electrode 113 controls the amount of electrons emitted from the cathode 112. The second grid electrode 114 focuses the electrons that have passed through the first grid electrode 113 toward the target T. The second grid electrode 114 has a cylindrical shape. The first grid electrode 113 is disposed between the cathode 112 and the second grid electrode 114. The energy ray tube 3 is fixed to one end of the cylindrical member 10.

The head unit 7 corresponds to the anode of the energy ray tube 3 in terms of potential. The head unit 7 has a cylindrical shape coaxial with the emission direction axis of the X-rays. The emission direction axis of the X-rays corresponds to the Z-axis. The head unit 7 has a hollow portion 7a that constitutes a part of the internal space R. The head unit 7 communicates with an insulating valve 6 that is coaxial with the emission direction axis on the electron gun 110 side of the hollow portion 7a. In this embodiment, the head unit 7 is at ground potential, and a negative high voltage is supplied from the power supply unit 2 to the electron gun 110 of the energy ray tube 3 via the high voltage power supply unit 4. The voltage applied to the energy ray tube 3 by the power supply unit 2 is, for example, -10 kV to -500 kV.

Next, the structure of the energy ray tube will be described in more detail with reference to Figures 2 to 4. Figure 3 shows the head portion 7 of the energy ray tube 3. Figure 4 is a partially enlarged view of the head portion 7. As shown in Figures 3 and 4, the head portion 7 comprises a housing portion 40, a window portion 50, and a frame portion 60. An internal space R is surrounded by the housing portion 40 and the window portion 50. The housing portion 40, the window portion 50, and the frame portion 60 form a part of the internal space R.

The housing 40 has a tubular shape. For example, the housing 40 has a cylindrical shape. The housing 40 extends in the Z-axis direction. An opening 40a is formed on one end of the housing 40, and an opening 40b is formed on the other end. The housing 40 includes an edge 41 that defines the opening 40a. The edge 41 is an annular flat portion that is countersunk to a depth d around the entire circumference of one end face of the housing 40. The edge 41 includes a flat bottom surface 45 that extends along a direction intersecting with the tube axis direction of the energy ray tube 3, and a side surface 46 that extends along the tube axis direction of the energy ray tube 3. In this embodiment, the tube axis direction of the energy ray tube 3 corresponds to the Z-axis direction. The openings 40a and 40b open in the Z-axis direction. In other words, the opening direction of the openings 40a and 40b is the Z-axis direction. The openings 40a and 40b of the housing 40 are continuous with the internal space R. The opening 40a is located at the edge of the internal space R. The housing 40 contains metal. The housing 40 is mainly made of a metal material. An example of the metal material is stainless steel. The housing 40 is made of stainless steel, for example.

The window portion 50 constitutes a window through which energy rays pass. When viewed from the Z-axis direction, the window portion 50 covers the opening 40a. The window portion 50 includes an end portion 51 and a central portion 52. The end portion 51 is an edge region. The central portion 52 is surrounded by the end portion 51 and is a central region in which a window 53 described later is disposed. A through hole H is formed in the window portion 50 at approximately the center of the central portion 52. The through hole H is a passage hole for the electron beam B. The central portion 52 is continuous with the end portion 51. The end portion 51 is a frame-shaped region and faces the edge portion 41 when viewed from the Z-axis direction. For example, the end portion 51 has a circular ring shape. When viewed from the Z-axis direction, the central portion 52 covers the opening 40a. In this embodiment, the end portion 51 and the central portion 52 are an integral member and are not divided by a strict boundary, but rather define an approximate region in the window portion 50. The central portion 52 does not face the edge portion 41 in the Z-axis direction. The window portion 50 includes a target T, a window 53, and a window holding member 54. As shown in FIG. 2, the target T is provided on the surface of the window 53 facing the internal space R, and generates X-rays by irradiation with an electron beam B from the electron gun 110. The target T is made of, for example, a metal material. Examples of metal materials include tungsten. The target T is made of, for example, tungsten.

The window 53 transmits energy rays. The window 53 is disposed in the central portion 52. The window 53 blocks and seals the through hole H. In other words, the window 53 constitutes a part of the central portion 52. The window 53 has a disk shape. The window 53 holds the target T on the side of the internal space R. In this embodiment, the energy ray tube 3 is a transmission type X-ray tube, and the X-rays generated in the target T transmit through the window 53 and are irradiated to the outside. The window 53 is formed of, for example, a material that is highly transparent to energy rays. Examples of materials for the window 53 include beryllium and diamond. The window 53 is made of, for example, beryllium or diamond.

The window holding member 54 constitutes the main body of the window portion 50 and holds the window 53. The window 53 is positioned by the window holding member 54. The window holding member 54 has a disk shape. In this embodiment, the window holding member 54 is composed of an end portion 51 and a central portion 52. That is, when viewed from the Z-axis direction, the window holding member 54 faces the edge portion 41 at the end portion 51 and covers the opening 40a at the central portion 52. The window holding member 54 is made of, for example, a metal material. Examples of metal materials include molybdenum. The window holding member 54 is made of, for example, molybdenum.

The frame portion 60 fixes the window portion 50 to the housing portion 40. The frame portion 60 is provided continuously along the edge portion 41 and has a frame shape. The frame portion 60 is formed continuously in a frame shape without being divided. For example, the frame portion 60 has a circular ring shape. As shown in FIG. 4, the frame portion 60 is fixed to the window holding member 54 of the window portion 50 and the edge portion 41 of the housing portion 40. As a result, the internal space R is hermetically sealed. The frame portion 60 is made of, for example, a metal material. Examples of the metal material include Kovar. The frame portion 60 is made of, for example, Kovar. The thermal expansion coefficient of the housing portion 40 is greater than that of the window portion 50. At least the thermal expansion coefficient of the edge portion 41 of the housing portion 40 is greater than the thermal expansion coefficients of the window 53, the window holding member 54, and the frame portion 60. The thermal expansion coefficient of the frame portion 60 is approximately equal to the thermal expansion coefficient of the window holding member 54. The thermal expansion coefficient of the window 53 is smaller than the thermal expansion coefficients of the housing portion 40, the window holding member 54, and the frame portion 60.

The frame portion 60 includes a first frame portion 61 and a second frame portion 62. In this embodiment, the first frame portion 61 and the second frame portion 62 each have a frame shape and are integrally formed. The first frame portion 61 and the second frame portion 62 are located on the same plane along a direction perpendicular to the Z-axis direction.

The first frame 61 is fixed to the edge 41 of the housing 40. The first frame 61 forms an outer edge 61a of the frame 60 at the end away from the tube axis of the energy ray tube 3. The edge 41 has a bottom surface 45 facing the other side of the first frame 61 and a side surface 46 facing the outer edge 61a. The first frame 61 is joined to the housing 40 by, for example, welding. The first frame 61 is joined to the housing 40 by, for example, laser welding in the end region on the outer edge 61a side. At least a part of the first frame 61 is located outside the window 50 when viewed from the Z-axis direction. The end region on the outer edge 61a side is located outside the window 50 when viewed from the Z-axis direction. At least a part of the first frame 61 is exposed without being covered by the window 50 when viewed from the Z-axis direction. Therefore, in laser welding, the laser is irradiated to the welded portion without being blocked by the window 50.

The second frame portion 62 is arranged so as to overlap with the central portion 52 when viewed from the Z-axis direction. In other words, the second frame portion 62 is arranged in a region that overlaps with the opening 40a when viewed from the Z-axis direction. The second frame portion 62 does not overlap with the edge portion 41 when viewed from the Z-axis direction. The second frame portion 62 is fixed to the window portion 50. The second frame portion 62 is joined to a portion of the surface 50a of the window portion 50 on the internal space R side that corresponds to the central portion 52. The surface 50a is the surface of the surface 50a of the window portion 50 that faces the opening 40a.

In this embodiment, the head portion 7 further includes a joint portion 70. The joint portion 70 seals the internal space R and fixes the frame portion 60 and the window portion 50. The joint portion 70 is disposed between the second frame portion 62 and the window portion 50. The joint portion 70 joins one side of the second frame portion 62 to the surface 50a of the window portion 50. The joint portion 70 includes a first joint portion 71 and at least one second joint portion 72. A separation portion 75 is disposed between the first joint portion 71 and the at least one second joint portion 72. The separation portion 75 separates the first joint portion 71 and the at least one second joint portion 72. The separation portion 75 is a gap formed between the first joint portion 71 and the at least one second joint portion 72. The separation portion 75 is defined by the first joint portion 71 and the at least one second joint portion 72. The first joint portion 71 and the second joint portion 72 are formed, for example, by brazing. In other words, the frame portion 60 is joined to the window portion 50 by, for example, brazing. The first joining portion 71 and the second joining portion 72 are made of a brazing material. An example of the brazing material is an alloy. An example of the alloy is silver brazing.

FIGS. 5(a) to 5(c) and 6(a) to 6(b) are schematic diagrams showing the configuration of the joint 70. FIG. 5(a) shows the joint 70 in this embodiment. In the configuration shown in FIG. 5(a), the joint 70 includes a first joint 71 and at least one second joint 72.

The first joint 71 is a sealing part that hermetically seals the internal space R surrounded by the housing part 40 and the window part 50. The first joint 71 is arranged continuously in a frame shape along the edge of the opening 40a. The first joint 71 fixes the frame part 60 and the window part 50 in a frame-shaped region α1 of the surface 50a that is along the edge of the opening 40a. In other words, the first joint 71 continuously surrounds the tube axis of the energy ray tube 3 without being divided. The first joint 71 has, for example, a circular ring shape.

The second joint 72 is disposed along the first joint 71. The second joint 72 is a reinforcing portion that reinforces the joint between the window portion 50 and the frame portion 60 by the first joint 71. When viewed from the Z-axis direction, the second joint 72 is disposed outside the area 71a surrounded by the first joint 71.

In the configuration shown in FIG. 5(a), the second joint 72 has a frame shape. The second joint 72 is continuously arranged in a frame shape along the edge of the opening 40a. The second joint 72 fixes the frame portion 60 to the window portion 50 in a frame-shaped region α2 along the edge of the opening 40a on the surface 50a. In other words, the second joint 72 surrounds the tube axis of the energy ray tube 3 continuously without being divided. When viewed from the Z-axis direction, the region α2 surrounds the region α1. In other words, when viewed from the Z-axis direction, the second joint 72 surrounds the first joint 71. The second joint 72 has, for example, a ring shape. The width of the second joint 72 is smaller than the width of the first joint 71 when viewed from the opening direction of the opening 40a. The width of the first joint 71, the width of the second joint 72, and the width of the separation portion 75 are each a length that extends continuously in a direction perpendicular to the Z-axis direction. The area of the bonding region of the second bonding portion 72 is smaller than the area of the bonding region of the first bonding portion 71 when viewed from the opening direction of the opening 40a. The areas of the bonding region of the first bonding portion 71, the area of the second bonding portion 72, and the area of the bonding region of the separation portion 75 are each the areas of the bonding region when viewed from the Z-axis direction. The bonding region of the first bonding portion 71 is the area where the first bonding portion 71 and the window portion 50 are bonded, or the area where the first bonding portion 71 and the frame portion 60 are bonded. The bonding region of the second bonding portion 72 is the area where the second bonding portion 72 and the window portion 50 are bonded, or the area where the second bonding portion 72 and the frame portion 60 are bonded.

In this embodiment, the separation portion 75 is disposed along the edges of the first joint portion 71 and the second joint portion 72. The separation portion 75 is disposed continuously in a frame shape. The separation portion 75 surrounds the first joint portion 71 continuously without being interrupted. The width of the first joint portion 71 is greater than the width of the second joint portion 72. The width of the separation portion 75 is smaller than the width of the first joint portion 71 and the width of the second joint portion 72. The width of the separation portion 75 is the length extending in a direction perpendicular to the Z-axis direction in a cross section in the Z-axis direction.

Figures 5(b) to 5(c) and 6(a) to 6(b) respectively show joints 70A, 70B, 70C, and 70D in a modified example of this embodiment. The configurations of joints 70A, 70B, 70C, and 70D are generally similar or the same as joint 70 in the embodiment described above. Below, differences between the embodiment and the modified example will be mainly described.

The configuration of the joints 70A and 70B shown in Fig. 5(b) and Fig. 5(c) differs from the configuration of the joint 70 shown in Fig. 5(a) only in that the first joint 71 and the second joint 72 are connected by a connecting portion 76. The joints 70A and 70B are connected by a plurality of connecting portions 76. When viewed from the Z-axis direction, the plurality of connecting portions 76 are connected to a part of the outer edge of the first joint 71 and to a part of the inner edge of the second joint 72. In the joints 70A and 70B, the first joint 71, the second joint 72, and the connecting portion 76 form a plurality of separation portions 75. The first joint 71, the second joint 72, and the plurality of connecting portions 76 are integrally formed.

The configuration of the joint 70A shown in FIG. 5(b) differs from the configuration of the joint 70 shown in FIG. 5(a) only in that it includes a connecting portion 76. In the joint 70A, the region between the first joint 71 and the second joint 72 is divided by a plurality of connecting portions 76. A plurality of separation portions 75 of the same shape are formed by the first joint 71, the second joint 72, and the plurality of connecting portions 76. The joint 70A includes, for example, two connecting portions 76. The two connecting portions 76 are positioned in the same straight line.

5(c) is different from the configuration of the joint 70 shown in FIG. 5(a) only in that a plurality of circular separation portions 75 are formed by a plurality of second joint portions 72 and a plurality of connecting portions 76. A single circular separation portion 75 is defined by one second joint portion 72 and one connecting portion 76. A single second joint portion 72 and a single connecting portion 76 form a single annular portion. The multiple second joint portions 72 are spaced apart from each other and connected to each other via the first joint portion 71. The multiple connecting portions 76 are spaced apart from each other and connected to each other via the first joint portion 71 and the corresponding second joint portion 72. The multiple second joint portions 72 and the multiple connecting portions 76 are, for example, arranged at equal intervals along the outer edge of the first joint portion 71. The area of the joint region of one second joint portion 72 is smaller than the area of the joint region of the first joint portion 71 when viewed from the opening direction of the opening 40a. The area of the bonding region of the first bonding portion 71 and the area of the bonding region of one second bonding portion 72 are each the areas of the bonding regions when viewed from the Z-axis direction.

The configuration of the joints 70C, 70D shown in Fig. 6(a) and Fig. 6(b) differs from the configuration of the joint 70 shown in Fig. 5(a) only in that the joints 70C, 70D include a plurality of second joints 72 that are spaced apart from one another. The plurality of second joints 72 are spaced apart from one another. Gaps 77 are disposed between the plurality of second joints 72. Each second joint 72 is formed, for example, in the same shape. Each second joint 72 is disposed, for example, at equal intervals along the outer edge of the first joint 71.

In the configuration of the joint 70C shown in FIG. 6(a), the second joints 72 are spaced apart from one another and are arranged in a discontinuous frame shape. The second joints 72 are spaced apart from one another. The joint 70C includes, for example, four second joints 72. The four second joints 72 are arranged, for example, at equal intervals. The four second joints 72 form, for example, four gaps 77. Each gap 77 is formed by two adjacent second joints 72. Each gap 77 is continuous with the separation portion 75. For example, the interval between the adjacent second joints 72, i.e., the width of the gap 77, is smaller than the width of each second joint 72.

In the configuration of the joint 70D shown in FIG. 6(b), the multiple second joints 72 are arranged in a frame-shaped region surrounding the first joint 71. In the joint 70D, the multiple second joints 72 are also spaced apart from one another. The multiple second joints 72 are arranged independently of one another. The multiple second joints 72 are arranged, for example, at equal intervals. Each second joint 72 has, for example, a circular shape. Each gap 77 is formed by two adjacent second joints 72. Each gap 77 is continuous with the separation portion 75. The interval between the adjacent second joints 72, i.e., the width of the gap 77, is, for example, equal to or less than the diameter of each second joint 72.

Next, an energy ray tube in a modified example of this embodiment will be described with reference to Figs. 7(a) and 7(b). Figs. 7(a) and 7(b) are partial enlarged views of an energy ray tube in a modified example of this embodiment. This modified example is generally similar or the same as the embodiment described above. The modified example shown in Fig. 7(a) differs from the embodiment described above in that a groove 55 is provided in the window portion 50. The modified example shown in Fig. 7(b) differs from the embodiment described above in that a groove 65 is provided in the frame portion 60. Below, the differences between the embodiment and the modified example described above will be mainly described.

In the configuration shown in FIG. 7(a), the window portion 50 includes a groove 55 formed to face the second frame portion 62 of the frame portion 60 in the Z-axis direction. The groove 55 has a depth in the thickness direction of the window portion 50. The thickness direction of the window portion 50 coincides with the Z-axis direction. The groove 55 is open toward the frame portion 60. In this embodiment, the groove 55 is formed, for example, continuously in a frame shape.

The region α1 in which the first bonding portion 71 is disposed and the region α2 in which the second bonding portion 72 is disposed are disposed so as to sandwich the groove 55. In other words, when viewed from the Z-axis direction, the first bonding portion 71 and the second bonding portion 72 are separated in the region in which the groove 55 is disposed. When viewed from the Z-axis direction, the bonding portion 70 is not disposed in the region in which the groove 55 is disposed. A separation portion 75 is disposed at a position opposite the groove 55. In other words, the separation portion 75 is disposed along the groove 55.

In the configuration shown in FIG. 7(b), the frame portion 60 includes a groove 65 formed to face the center portion 52 of the window portion 50 in the Z-axis direction. The groove 65 opens toward the surface 50a of the window portion 50. In this embodiment, the groove 65 is formed, for example, in a continuous ring shape.

When viewed from the Z-axis direction, the first joint 71 and the second joint 72 are arranged to sandwich the groove 65. In other words, when viewed from the Z-axis direction, the first joint 71 and the second joint 72 are separated in the region where the groove 65 is formed. When viewed from the Z-axis direction, the joint 70 is not arranged in the region where the groove 65 is formed. A separation portion 75 is arranged at a position opposite the groove 65. In other words, the separation portion 75 is arranged along the groove 65.

Next, a part of the manufacturing method of the energy ray tube will be described with reference to Figures 8 and 9. Figures 8 and 9 are diagrams showing the manufacturing process of the energy ray tube.

First, as shown in FIG. 8, the window 53 provided with the target T, the window holding member 54, and the frame 60 are connected to each other. Arrow A1 indicates the direction in which the window 53 is attached to the window holding member 54. Arrow A2 indicates the direction in which the window holding member 54 is attached to the frame 60. The window 53 is fixed to approximately the center of the central portion 52 of the window holding member 54. The frame 60 is fixed to the window holding member 54 by brazing. Specifically, one surface of the second frame 62 is fixed to the window holding member 54 by brazing. At this time, the window holding member 54 and the second frame 62 are overlapped in a direction perpendicular to the window 53. Brazing is performed, for example, at 600 to 1000°C.

Next, a vacuum heat treatment is performed on the unit 80 in which the window 53, the window holding member 54, and the frame 60 are connected to each other. The vacuum heat treatment is performed at a temperature of, for example, 200 to 1000°C.

Next, as shown in FIG. 9, the unit 80 is fixed to the housing part 40. Arrow A3 indicates the direction in which the unit 80 is attached to the housing part 40. This causes the unit 80 to be fitted into the edge part 41 of the housing part 40. With the unit 80 fitted into the edge part 41 of the housing part 40, the frame part 60 and the housing part 40 are fixed by welding. Specifically, the first frame part 61 of the frame part 60 and the housing part 40 are welded by a laser. The joining of the unit 80 and the housing part 40 is performed at room temperature.

Next, the insulation valve 6 and other components are combined with the unit 90, which is made by connecting the unit 80 and the housing 40, and the internal space R is then evacuated. The heating process is carried out at a temperature of, for example, 200 to 650°C. After the internal space R is evacuated by the heating process, the energy ray tube 3 is sealed and cooled to room temperature. The energy ray tube 3 is manufactured by carrying out the above processes.

Next, the effect of the energy ray tube 3 will be described. FIG. 10 shows a portion of an energy ray tube of a comparative example. In the configuration shown in FIG. 10, the energy ray tube has a joint 210 instead of the joint 70. The joint 210 differs from the joint 70 in that the separation portion 75 is not provided.

In FIG. 10, the force acting on the joint 210 of this energy ray tube is shown. For example, when the energy ray tube is placed in a high-temperature environment, the housing 40 thermally expands in a direction perpendicular to the Z-axis direction. The frame 60 is fixed to the housing 40 at the bottom surface 45. The frame 60 is fixed to the window 50 by the joint 210 in the region α. When the thermal expansion coefficient of the housing 40 is greater than that of the window 50 and the frame 60, the housing 40 expands relatively more than the window 50 and the frame 60 under the same heating conditions. In other words, the housing 40 deforms relatively more than the window 50 and the frame 60. In other words, the window 50 and the frame 60 are relatively less likely to deform due to heat than the housing 40. Therefore, the forces A4 and A5 due to the difference in thermal expansion coefficient between the housing 40 and the window 50 and the frame 60 are applied to the joint 210.

Forces A4 and A5 are forces that occur in opposite directions perpendicular to the Z-axis direction. Therefore, stress due to forces A4 and A5 is applied to joint 210. This stress is, for example, shear stress. If the magnitude of this stress exceeds the mechanical strength of joint 210, damage such as cracks may occur in joint 210, and the sealing state of internal space R may be compromised.

In this embodiment, at least one second joint 72 is arranged along the first joint 71 that seals the internal space R. Between the first joint 71 and at least one second joint 72, a separation portion 75 defined by the first joint 71 and the second joint 72 is formed. Therefore, at least one second joint 72 ensures the strength of the fixed portion between the housing part 40 and the window part 50. For example, even if damage such as a crack occurs in the second joint 72, the damage caused in the second joint 72 is unlikely to affect the first joint 71 due to the separation portion 75 arranged between the first joint 71 and the second joint 72. Therefore, the sealing state of the internal space R is unlikely to be impaired. Since the window part 50 is fixed to the housing part 40 by the first joint 71 and the second joint 72, the strength of the joint portion between the housing part 40 and the window part 50 is adjusted, and cracks in the window part 50 are unlikely to occur. Therefore, the sealing state of the internal space R can be suppressed from being impaired.

At least one second joint 72 is disposed outside the area 71a surrounded by the first joint 71 when viewed from the opening direction of the opening 40a. As a result of intensive research and study, the inventors of the present application have found that when stress occurs in the joint 70 due to the difference in thermal expansion coefficient between the housing part 40 and the window part 50 and frame part 60, the stress applied to the outer edge of the first joint 71 is greater than the stress applied to the inner edge of the first joint 71. As a result of further research and study, they have found that the stress applied to the outer edge of the first joint 71 is reduced by forming the second joint 72 outside the area 71a surrounded by the first joint 71. Therefore, according to the joints 70, 70A, 70B, 70C, and 70D, the sealing state at the first joint 71 can be further prevented from being damaged.

In the joints 70 and 70A, at least one second joint 72 is arranged in a continuous frame shape along the edge of the first joint 71 outside the internal space R. In this case, the stress applied to the first joint can be uniformly reduced by the second joint formed in a continuous frame shape. As a result, while the structure is easy to form the first joint 71 and the second joint 72, the loss of the sealing state of the internal space R and the occurrence of cracks in the window portion 50 can be further suppressed.

At least one second joint 72 in joints 70B, 70C, and 70D includes a plurality of second joints 72 that are arranged along the edge of the first joint 71 and spaced apart from one another. In this case, because the plurality of second joints 72 are spaced apart from one another, the effects of damage to the second joints 72 are prevented from spreading over a wide area. In other words, even if damage occurs to one second joint 72, it is unlikely to affect the occurrence of damage in other second joints 72.

The joints 70A and 70B include a connecting portion 76 that connects the first joint 71 and at least one second joint 72. In this case, a structure is realized that makes it easy to form the first joint 71, the second joint 72, and the separation portion 75.

In this embodiment, the width of at least one second joint 72 is smaller than the width of the first joint 71 when viewed from the opening direction of the opening 40a. Therefore, the mechanical strength of the second joint 72 is weaker than that of the first joint 71. Therefore, when stress is applied to the joint 70, damage such as cracks may occur in the second joint 72 before the first joint 71. The first joint 71, which is disposed away from the second joint 72 by the separation portion 75, is less likely to be damaged. In other words, the second joint 72 is a sacrificial bonding portion in the joint 70, and the stress applied to the first joint 71 is relieved by the sacrificial destruction of the second joint 72. As a result, damage to the first joint 71 that hermetically seals the internal space R can be suppressed. Therefore, the sealing state of the internal space R can be suppressed from being impaired.

In this embodiment, the sum of the width of the first joint 71 and the width of the second joint 72 is, for example, 1.0 mm to 20 mm. Within this range, the sealing state of the internal space is prevented from being impaired.

In this embodiment, the area of the bonding region of at least one second bonding portion 72 is smaller than the area of the bonding region of the first bonding portion 71 when viewed from the opening direction of the opening 40a. Therefore, the mechanical strength of the second bonding portion 72 is weaker than that of the first bonding portion 71. Therefore, when stress is applied to the bonding portion 70, damage such as cracks may occur in the second bonding portion 72 before the first bonding portion 71. The first bonding portion 71, which is disposed away from the second bonding portion 72 by the separation portion 75, is less likely to be damaged. In other words, the second bonding portion 72 is a sacrificial bonding portion in the bonding portion 70, and the stress applied to the first bonding portion 71 is relieved by the sacrificial destruction of the second bonding portion 72. As a result, damage to the first bonding portion 71 that hermetically seals the internal space R can be suppressed. Therefore, the sealing state of the internal space R can be suppressed from being impaired.

In the joints 70, 70A, 70B, 70C, and 70D, the first joint 71 and at least one second joint 72 are formed from a brazing material. In this case, the internal space R can be sealed in a configuration that is easy to manufacture.

The window portion 50A includes a groove 55 facing the separation portion 75. In this case, a structure is realized that makes it easy to form the separation portion 75 between the first bonding portion 71 and the second bonding portion 72. In particular, when the first bonding portion 71 and at least one second bonding portion 72 are formed of a brazing material, even if the brazing material gets into the separation portion 75, contact between the first bonding portion 71 and the second bonding portion 72 is suppressed.

The frame portion 60 is provided along the edge of the opening 40a and is fixed to the housing portion 40 by welding. The joint portion 70 fixes the window portion 50 and the frame portion 60. In this case, the internal space R can be easily sealed.

The frame portion 60A includes a groove 65 facing the separation portion 75. In this case, a structure is realized that makes it easy to form the separation portion 75 between the first bonding portion 71 and the second bonding portion 72. In particular, when the first bonding portion 71 and at least one second bonding portion 72 are formed of a brazing material, even if the brazing material gets into the separation portion 75, contact between the first bonding portion 71 and the second bonding portion 72 is suppressed.

When viewed from the Z-axis direction, the frame 60 is fixed to the housing 40 on the outside of the window 50. In this case, the frame 60 and the housing 40 can be easily welded together.

The housing 40 may include an edge 41 that defines the opening 40a. The window 50 includes an end 51 that faces the edge 41 in the Z-axis direction. In this case, even if an external force β is applied to the window 50, for example, as shown in FIG. 10, pressing the window 50 against the housing 40, the window 50 is supported by the edge 41. As a result, displacement between the window 50 and the housing 40 is suppressed. Therefore, the sealed state of the internal space R is less likely to be damaged. Furthermore, changes in the emission conditions of the energy rays that pass through the window 50 can also be suppressed.

The above describes the embodiments and variations of the present invention, but the present invention is not necessarily limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention.

For example, the energy ray tube is not limited to the energy ray tube 3 provided in the energy ray generating device. For example, it may be an energy ray detection tube in which energy rays are irradiated from the outside and detected. In this case, the energy rays enter the internal space R of the energy ray tube through the window portion 50.

In this embodiment, the window holding member 54 is fixed to the housing 40 via the frame 60. However, the window holding member 54 may be fixed directly to the housing 40. In this case, a groove similar to the groove 65 may be formed in the housing 40.

7(a) and 7(b) show a configuration in which groove 55 or groove 65 is formed. These grooves 55, 65 may be modified depending on the configuration of the joint 70. For example, grooves 55, 65 may be provided so as to form a plurality of spaced apart portions 75 as shown in Figs. 5(b) and 5(c). For example, grooves 55, 65 may be provided so as to form a plurality of second joint portions 72 as shown in Figs. 5(c), 6(a), and 6(b). Both grooves 55 and grooves 65 may be formed in the energy ray tube 3.

3...energy ray tube, 40...housing portion, 40a...opening, 41...edge portion, 50...window portion, 51...end portion, 53...window, 55, 65...groove, 60...frame portion, 70, 70A, 70B, 70C, 70D...joint portion, 71...first joint portion, 72...second joint portion, 75...separation portion, R...internal space, α1, α2...region.

Claims (11)

a window portion including a window that transmits an energy beam and a window holding member that holds the window ;
a housing portion having an opening covered by the window portion;
a joint portion that fixes the window holding member to the housing portion,
the window holding member is made of a metal material and has a through hole sealed in the window,
The joint is
a first joint portion that is continuously arranged in a frame shape along an edge of the opening and seals an internal space surrounded by the housing portion and the window portion;
and at least one second bonding portion disposed along the first bonding portion outside a region surrounded by the first bonding portion when viewed from an opening direction of the opening ,
a separation portion is disposed between the first bond portion and the at least one second bond portion ;
the first bonding portion and the at least one second bonding portion are formed of a brazing material and are arranged to overlap the window holding member so as to be spaced apart from an outer edge of the window holding member when viewed from the opening direction,
An energy ray tube, wherein the window does not overlap with the first joint portion and the second joint portion when viewed from the opening direction. The energy ray tube according to claim 1 , wherein the at least one second joint portion is disposed continuously in a frame shape along an edge of the first joint portion outside the internal space. 3. The energy ray tube of claim 1 , wherein the at least one second joint portion includes a plurality of second joint portions arranged along an edge of the first joint portion and spaced apart from one another. The energy ray tube according to claim 1 , wherein the joint portion further includes a connecting portion that connects the first joint portion and the at least one second joint portion. The energy ray tube according to claim 1 , wherein a width of the at least one second joint portion is smaller than a width of the first joint portion when viewed from an opening direction of the opening. 5. The energy ray tube according to claim 1, wherein an area of a bonding region of the at least one second bonding portion is smaller than an area of a bonding region of the first bonding portion when viewed from an opening direction of the opening. The energy ray tube of claim 1 , wherein the window portion includes a groove facing the spaced portion. a frame portion provided along an edge of the opening and fixed to the housing portion by welding;
The energy ray tube according to claim 1 , wherein the joint portion fixes the window portion to the frame portion. The energy ray tube of claim 8 , wherein the frame includes a groove facing the spaced apart portion. The energy ray tube according to claim 8 , wherein the frame portion is fixed to the housing portion on an outer side than the window portion when viewed from a direction in which the opening is opened. The housing portion includes an edge portion that defines the opening,
The energy ray tube according to claim 1 , wherein the window portion includes an end portion facing the edge portion in an opening direction of the opening.

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