JP6889619B2 - X-ray generator - Google Patents

Description

The present invention relates to an X-ray generator.

Patent Document 1 describes an X-ray source. This X-ray source includes an X-ray tube, a metal cylinder that houses a part of the X-ray tube in insulating oil, and a high-voltage power supply unit that supplies electric power to the X-ray tube. The high-voltage power supply unit has a high-voltage supply circuit and a connection line connected to the high-voltage supply circuit. The high voltage supply circuit and connecting wire are enclosed by being molded in an insulating block. The X-ray tube includes a rod-shaped anode and a bulb that holds and accommodates the anode in an insulated state. The base end of the anode projects downward from the bottom of the valve, to which one end of the compression spring is coupled. The other end of the compression spring is electrically connected to the high-voltage power supply unit to supply a high-voltage potential.

In the above-mentioned X-ray source, as a measure against electric discharge, the joint portion between the base end of the anode and the compression spring is surrounded by a high-pressure cap arranged on the insulating block, and these are further provided on the insulating block. Surrounded by walls. The lower part of the valve is arranged close to the wall portion of the insulating block so that the wall portion of the insulating block covers the enclosed area.

Japanese Patent No. 48899979

In recent years, a higher output X-ray source has been demanded. In order to increase the output, it is important to take measures against heat generated by the operation of the X-ray tube. For example, in the above-mentioned X-ray tube, improvement of heat dissipation efficiency via insulating oil is required. At this time, it is important that the insulating oil does not stay. In particular, it is important to suppress the retention of insulating oil in the region where the structure for discharge countermeasures is intricately arranged in order to improve the heat dissipation efficiency.

Therefore, an object of the present invention is to provide an X-ray generator capable of improving heat dissipation efficiency.

The X-ray generator according to the present invention includes an X-ray generator including an electron gun that generates an electron beam and a target that generates X-rays due to the incident of the electron beam, a vacuum housing that houses the X-ray generator, and a vacuum housing that houses the X-ray generator. An X-ray tube having a connection part held in a vacuum housing and used for electrical connection of the X-ray generation part, a power supply part having an insulating block for sealing a booster part for generating a high voltage voltage with an insulating material, and a power supply. A power supply unit that extends from the unit toward the connection unit and supplies a high voltage voltage to the X-ray tube via the connection unit, and at least a part of the X-ray tube including the connection unit, a power supply unit, and a power supply unit. A housing portion for accommodating the portion in insulating oil is provided, and a first wall portion protruding toward the power supply portion is formed in a part of the X-ray tube so as to surround the tip portion on the connection portion side of the feeding portion. A second wall made of an insulating material is formed in a part of the power supply unit so as to surround the base end portion on the power supply unit side of the power supply unit. It is a portion between and includes an intermediate portion exposed from the first wall portion and the second wall portion.

In this X-ray generator, a connecting portion used for electrical connection of the X-ray generating portion is held in the vacuum housing of the X-ray tube. A high voltage is supplied to the X-ray tube by a feeding portion extending from the power supply portion toward the connection portion. The vacuum housing is formed with a first wall portion that projects toward the power supply unit so as to surround the tip end portion of the power supply unit, and the power supply unit is made of an insulating material so as to surround the base end portion of the power supply unit. A second wall portion is formed, and the feeding portion includes an intermediate portion exposed from the first wall portion and the second wall portion between the tip end portion and the base end portion. In other words, the first wall portion and the second wall portion are separated from each other by the amount of the intermediate portion. As a result, the retention of insulating oil in the region between the first wall portion and the second wall portion is suppressed. Therefore, the heat dissipation efficiency of the insulating oil can be improved.

In the X-ray generator according to the present invention, the power feeding unit may include a wiring unit for electrically connecting the boosting unit and the connecting unit, and a tubular member made of a metal material and surrounding the wiring unit. Good. In this case, the wiring portion is protected by the tubular member.

In the X-ray generator according to the present invention, a high voltage may be applied to the tubular member. In this case, the discharge is suppressed by stabilizing the electric field around the wiring portion to which the high voltage voltage is applied.

In the X-ray generator according to the present invention, the wiring portion may include a plurality of cables electrically connected to the boosting portion and the connecting portion, and a base portion made of an insulating material and supporting the cables. In this case, the base portion can be used to stably extend the cable serving as the supply path of the high voltage voltage.

In the X-ray generator according to the present invention, the base portion includes a columnar portion along the cable and a plate-shaped portion provided at the end of the columnar portion on the connecting portion side, and the plate-shaped portion includes a plate-shaped portion. A plurality of connection terminals for electrically connecting the cable and the connection portion are provided, and a groove portion may be formed in the region between the connection terminals in the plate-shaped portion. In this case, the withstand voltage capability between the connection terminals is improved. As a result, it becomes possible to stably supply a high voltage.

In the X-ray generator according to the present invention, the connection portion is electrically connected to the electron gun, and the electron gun forms an electron emitting portion and an electric field for extracting electrons constituting an electron beam from the electron emitting portion. An electron amount control electrode, which is arranged between the electron emitting part and the drawing electrode and controls the amount of electrons drawn from the electron emitting part, may be included. As described above, it is possible to stably supply a high voltage to an electron gun having an extraction electrode and an electron amount control electrode that require control by a voltage difference smaller than that of the high voltage potential.

According to the present invention, it is possible to provide an X-ray generator capable of improving heat dissipation efficiency.

It is a vertical sectional view which shows the X-ray generator which concerns on embodiment. It is a vertical sectional view which shows the X-ray tube which concerns on embodiment. It is a schematic vertical sectional view which shows the high-voltage feeding part shown in FIG. 1 in an enlarged manner. It is a figure which shows the wiring part in the high voltage feeding part. It is a perspective view which shows the tubular member of a high voltage feeding part.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding elements may be designated by the same reference numerals, and duplicate description may be omitted.

FIG. 1 is a vertical cross-sectional view showing an X-ray generator according to an embodiment. FIG. 2 is a vertical cross-sectional view showing an X-ray tube according to an embodiment. As shown in FIGS. 1 and 2, the X-ray generator 100 is, for example, a microfocal X-ray source used for an X-ray nondestructive inspection for observing the internal structure of a subject. The X-ray generator 100 includes an X-ray tube 1, a housing C, and a power supply unit 80.

The X-ray tube 1 includes an X-ray generator G including an electron gun 110 and a target T. The X-ray tube 1 is a transmissive type that emits X-ray X that is generated by the electron beam B from the electron gun 110 incident on the target T and that has passed through the target T itself from the X-ray emission window 30. X-ray tube. The X-ray tube 1 is a vacuum-sealed X-ray tube provided with a vacuum housing 10 having a vacuum internal space R and which does not require replacement of parts or the like.

The vacuum housing 10 has a substantially columnar outer shape. The vacuum housing 10 includes a head portion 4 made of a metal material (for example, stainless steel) and an insulating valve 2 made of an insulating material (for example, glass). An X-ray emission window 30 is fixed to the head portion 4. An electron gun 110 is fixed to the insulating valve 2. The insulated valve 2 has a cylindrical outer diameter extending along the tube axis of the X-ray tube 1, and is directed toward the X-ray emitting window 30 on the end side facing the X-ray emitting window 30. It has a cylindrical recess 116 formed so as to extend along the tube axis of the X-ray tube 1 so as to be folded back.

Further, the insulating valve 2 is provided so as to seal the opening of the end portion of the recess 116 on the X-ray emission window 30 side, and has a stem portion 115 provided with a stem pin S used for power supply or the like. The stem portion (connecting portion) 115 holds the electron gun 110 at a predetermined position in the internal space R via the stem pin S. That is, the concave portion 116 extends the creepage distance between the head portion 4 and the electron gun 110 to improve the withstand voltage characteristic, and the electron gun 110 is arranged close to the target T in the internal space R, whereby the electron beam B Is easy to make microfocus.

The electron gun 110 controls the amount of electrons emitted from the heater 111 formed of filaments that generate heat by energization, the cathode (electron emission section) 112 that is heated by the heater 111 and becomes an electron emission source, and the cathode 112. The 1-grid electrode (electron amount control electrode) 113, the cylindrical second grid electrode 114 that focuses the electrons that have passed through the first grid electrode 113 toward the target T, and the second grid electrode 114 are electrically connected to each other. , The heater 111, the cathode 112, the first grid electrode 113, the stem portion 115, and the cover electrode 117 that surrounds a part of the recess 116 of the insulating valve 2. The second grid electrode 114 also functions as an extraction electrode that forms an electric field for extracting the electrons constituting the electron beam B. The first grid electrode 113 is arranged between the cathode 112 and the second grid electrode 114. The cover electrode 117 is an electrode including an inclined portion whose diameter increases from one end side to the other end side and a cylindrical portion extending along the tube axis of the X-ray tube 1, and is an insulating valve 2. It is arranged away from. One end of the cover electrode 117 is fixed to the second grid electrode 114, and at least the cylindrical portion of the other end side is the end region of the stem portion 115 (connection portion) and the recess 116 on the X-ray emission window 30 side. It extends to surround. The X-ray tube 1 is fixed to one end side of a tubular member 70 described later. An exhaust pipe (not shown) is attached to the X-ray tube 1, and the inside is evacuated through the exhaust pipe to be evacuated.

The housing C of the X-ray generator 100 includes a tubular member 70 and a power supply unit case 84 that houses an insulating block 81 described later as a part of the power supply unit 80. The tubular member 70 is made of metal and constitutes the main body of the accommodating portion H, which will be described later. The tubular member 70 has a cylindrical shape with openings at both ends thereof, and has an internal space I. In the tubular member 70, the insulating valve 2 of the X-ray tube 1 is inserted into the opening 70a on one end side thereof. As a result, the tubular member 70 accommodates at least a part of the X-ray tube 1. More specifically, the tubular member 70 accommodates at least a portion of the stem portion 115 and the insulated valve 2 that holds the stem portion 115 in the internal space I, and in the present embodiment, accommodates the entire insulated valve 2. doing.

The mounting flange 3 of the X-ray tube 1 is in contact with one end surface of the tubular member 70 and is fixed with screws or the like. As a result, the X-ray tube 1 is fixed at the opening 70a of the tubular member 70 while sealing the opening 70a. Insulating oil 71, which is a liquid electrically insulating substance, is sealed in the internal space I of the tubular member 70.

The power supply unit 80 has a function of supplying electric power to the X-ray tube 1. The power supply unit 80 includes an insulating block 81 made of a molded solid insulating material, for example, an epoxy resin which is an insulating resin, a boosting unit 82 molded in the insulating block 81, and a power supply that accommodates them and exhibits a rectangular box shape. It has a part case 84 and. The booster unit 82 generates a high voltage voltage V by adjusting the boost voltage v generated by boosting the introduction voltage introduced from the outside of the X-ray generator 100 as necessary based on various conditions. The insulating block 81 seals the booster portion 82 with an insulating material (epoxy resin). The other end side of the tubular member 70 (the side opposite to the one end side on the X-ray tube 1 side) is fixed to the power supply unit 80 (power supply unit case 84). As a result, the opening 70b on the other end side of the tubular member 70 is sealed, and the insulating oil 71 is airtightly sealed in the internal space I of the tubular member 70. The tubular member 70 accommodates a part (at least a wall portion 83, which will be described later) of the insulating block 81 on the stem portion 115 side in the internal space I.

A high-voltage power feeding unit (feeding unit) 90 including a cylindrical metal member electrically connected to the boosting unit 82 is arranged on the insulating block 81. The power supply unit 80 is electrically connected to the X-ray tube 1 via the high voltage power supply unit 90. More specifically, one end (the tip 90t, which will be described later) side of the high-voltage power feeding portion 90 on the X-ray tube 1 side is inserted into the recess 116 of the insulating valve 2 of the X-ray tube 1, and the stem portion 115 is evacuated. It is electrically connected to the stem pin S protruding from the internal space R. At the same time, the other end (base end 90b, which will be described later) side of the high voltage power feeding unit 90 on the power supply unit 80 side is fixed to the insulating block 81 in a state of being electrically connected to the boosting unit 82. The tubular member 70 accommodates the high-voltage power feeding unit 90 in the internal space I.

In the insulating block 81, the tubular member 70 and the power supply unit 80 (power supply unit) have an annular wall portion (second wall portion) 83 coaxial with the X-ray tube 1 separated from the X-ray tube 1 and the tubular member 70. It is provided so as to project toward the stem portion 115 so as to shield the connection portion with the case 84) from the high voltage feeding portion 90. As a result, the wall portion 83 is arranged and accommodated in the internal space I of the tubular member 70. Further, the inner circumference and the outer circumference of the wall portion 83 have a structure recessed inside the insulating block 81 (on the boosting portion 82 side) from the fixed portion of the high voltage feeding portion 90 in the insulating block 81. As a result, in the insulation block 81, the creepage distance from the fixed portion of the high-voltage power feeding portion 90, which is a high-voltage potential due to the high-voltage voltage V, to the tubular member 70, which is a ground potential, and the power supply portion case 84 is further increased, and the withstand voltage capacity is improved. I'm letting you. In the present embodiment, the target T (anode) is set as the ground potential, and the boost voltage v (-100 kV in the present embodiment) included in the range of −10 kV to −500 kV from the power supply unit 80 is based on various conditions. The high-voltage voltage V, which is a negative voltage adjusted in the above manner, is supplied to the X-ray tube 1 (electron gun 110) via the high-voltage power feeding unit 90. As described above, in the tubular member 70 provided with the internal space I, the opening 70a on one end side thereof is sealed by the X-ray tube 1, and the opening 70b on the other end side is sealed by the power supply unit 80 (insulation block 81 and power supply unit case 84). It is stopped, and the insulating oil 71 is sealed in the sealed space. Then, in the space, at least a part (insulation valve 2) of the X-ray tube 1 including the stem part 115, a high-voltage power supply part 90, and a part (wall part 83) of the power supply part 80 (insulation block 81) are insulated. By accommodating in the oil 71, the space becomes the accommodating portion H.

The X-ray tube 1 includes a vacuum housing 10 and a target portion 20. In the description of the present embodiment, the side in the direction in which the X-ray tube 1 emits X-rays is simply referred to as "X-ray emitting side" or "upper side". On the X-ray emitting side of the vacuum housing 10, a head portion 4 is provided as a wall portion that defines the internal space R. The head portion 4 is formed of a metal material (for example, stainless steel) and potentially corresponds to the anode of the X-ray tube 1. The head portion 4 has openings at both ends and exhibits a substantially cylindrical shape coaxial with the emission direction axis of X-ray X. The head portion 4 communicates with the insulating valve 2 coaxial with the emission direction axis at the opening on the other end side of the electron gun 110 side (see FIG. 2).

The target portion 20 is fixed to the head portion 4. The target portion 20 is provided on the surface of the X-ray emission window 30 provided so as to seal the opening 14 of the vacuum housing 10 (head portion 4) and the internal space R side of the X-ray emission window 30. It has a target T and. The target T generates X-rays due to the incident of the electron beam B. As the target T, for example, tungsten is used. The X-ray emission window 30 has a disk shape. The X-ray emission window 30 is made of a material having high X-ray transparency such as beryllium or diamond.

Subsequently, the structure of the high-voltage power feeding unit 90 in the X-ray generator 100 will be specifically described. FIG. 3 is a schematic vertical sectional view showing an enlarged view of the high-voltage power feeding unit shown in FIG. FIG. 4 is a diagram showing a wiring unit in the high voltage power feeding unit. FIG. 4A is a side view, and FIG. 4B is a plan view. FIG. 5 is a perspective view showing a tubular member of the high-voltage power feeding unit. As shown in FIGS. 1, 3 to 5, the high voltage power feeding unit 90 extends from the insulating block 81 of the power supply unit 80 toward the stem portion 115 of the insulating valve 2, and transmits the high voltage voltage V from the boosting unit 82 to the X-ray tube. Supply to 1. The high-voltage power supply unit 90 is not only a voltage supply member from the booster unit 82 to the X-ray tube 1 but also a current supply member.

As described above, a wall portion (second wall portion) 83 is formed at one end of the insulation block 81 on the insulation valve 2 side. The base end portion 90b of the high-voltage power feeding portion 90 is arranged in the recess 83c defined by the wall portion 83, and is surrounded by the wall portion 83. In other words, the insulating block 81 is formed with a wall portion 83 projecting toward the stem portion 115 so as to surround the base end portion 90b of the high-voltage power feeding portion 90.

On the other hand, as described above, the insulating valve 2 is provided with a recess 116. The tip 90t, which is the end opposite to the base end 90b of the high-voltage power feeding portion 90, is arranged in the recess 116 and is surrounded by the wall portion 2a that defines the recess 116. In other words, the insulating valve 2 is formed with a wall portion (first wall portion) 2a protruding toward the insulating block 81 so as to surround the tip portion 90t on the stem portion 115 side of the high voltage feeding portion 90. Further, in the internal space R of the region formed by the wall portion 2a, together with the stem portion 115, at least the periphery of the connection portion with the stem portion 115 at the tip portion 90t of the high-voltage power feeding portion 90, more preferably a recess at the tip portion 90t. The other end side of the cover electrode 117 extends so as to surround about half of the region arranged in the 116.

The top portion 2p of the wall portion 2a of the insulation valve 2 and the top portion 83p of the wall portion 83 of the insulation block 81 are separated from each other in the extending direction of the high-voltage power feeding portion 90. Therefore, the high-voltage power feeding unit 90 includes a portion other than the tip end 90t and the base end 90b, which is not surrounded by the wall portion 2a and the wall portion 83 when viewed from the direction intersecting (orthogonal) in the extending direction of the high-voltage feeding unit 90. I'm out. In other words, the high-voltage power feeding unit 90 is a portion between the tip end portion 90t and the base end portion 90b, and includes an intermediate portion 90m exposed from the wall portion 2a and the wall portion 83. The base end portion 90b, the intermediate portion 90m, and the tip end portion 90t are arranged in order from the insulating block 81 toward the insulating valve 2 (hereinafter, may be referred to as “height direction”).

The high-voltage power supply unit 90 includes a wiring unit 91 for electrically connecting the booster unit 82 and the stem unit 115, and a tubular member 92 made of a metal material (for example, stainless steel, aluminum, etc.) and surrounding the wiring unit 91. ,including. The wiring unit 91 includes a plurality of (for example, five) cables 93 that are electrically connected to the booster unit 82a and the stem unit 115, and a base unit 94 that is made of an insulating material and supports the cables 93. The base portion 94 includes a columnar portion 95 along the cable 93, a plate-shaped portion 96 provided at the end of the columnar portion 95 on the stem portion 115 side, and an end of the columnar portion 95 opposite to the stem portion 115. Includes a plate-shaped portion 97 provided in the portion. In the present embodiment, the cable 93 is connected to each configuration of the electron gun 110 via the stem pin S (heater 111, cathode 112, first grid electrode 113, second grid electrode 114 (and cover electrode 117)). A high voltage voltage V for supplying to is supplied. More specifically, the boost voltage v generated by the booster 82 is supplied by the control unit provided in the booster 82 to the heater 111, the cathode 112, the first grid electrode 113, and the second grid electrode 114 (and the cover electrode). A high voltage V is appropriately adjusted as necessary so that the voltage value corresponds to the function of 117), and is supplied to each cable 93. That is, the high voltage voltage V is not limited to a predetermined one voltage based on the boosted voltage v, and indicates a voltage in which the difference from the reference is included in the predetermined range L with the boosted voltage v as a reference. For example, the absolute value of the boost voltage v is preferably 10 kV or more and 500 kV or less. In this case, the high-voltage voltage V is a voltage in a range in which the difference from the reference is 4% or less of the boost voltage v with respect to the boost voltage v, and the absolute value in the predetermined range L including the difference from the reference. The maximum value is preferably 25 V or more and 20 kV or less. More preferably, the absolute value of the boosted voltage v is 10 kV or more and 300 kV or less, and the high voltage voltage V is a voltage in a range in which the difference from the reference is 2% or less of the boosted voltage v with respect to the boosted voltage v. Moreover, the maximum value of the absolute value in the predetermined range L including the difference from the reference is 50 V or more and 6 kV or less. Since the difference from the reference is 0% (that is, 0V) of the boosted voltage v, the case where the high voltage V is equal to the boosted voltage v is also included. In this case, the boosted voltage v may be directly supplied without adjustment by the control unit.

The columnar portion 95 is formed in a columnar shape by, for example, an insulating material. The cable 93 extends along the columnar portion 95 in a state of having a predetermined deflection. Both ends of the cable 93 are connected to the plate-shaped portion 96 and the plate-shaped portion 97. The columnar portion 95 rotatably supports at least one of the plate-shaped portion 96 and the plate-shaped portion 97. Therefore, for example, the bending of the cable 93 can be adjusted by rotating the plate-shaped portion 96 with respect to the columnar portion 95. Further, since the cable 93 can be wound around the columnar portion 95, it is possible to prevent the cable 93 from coming into contact with the inner wall surface of the tubular member 92. Therefore, it is also preferable for the withstand voltage characteristic between the tubular member 92 and the cable 93.

The plate-shaped portion 96 and the plate-shaped portion 97 are formed in a disk shape by, for example, an insulating material, and the diameter thereof is larger than the diameter of the columnar portion 95 and smaller than the inner diameter of the tubular member 92. There is. The plate-shaped portion 96 is formed with a plurality of groove portions 96g extending radially from the center 96c of the plate-shaped portion 96. The groove 96g extends from the outer edge 96e of the plate-shaped portion 96 toward the center 96c of the plate-shaped portion 96, and ends without reaching the center 96c. As a result, the outer edge portion of the plate-shaped portion 96 is divided into a plurality of fan-shaped portions 96p. An opening is provided in each of the fan-shaped portions 96p. The opening of a part of the fan-shaped portion is made into a connection terminal 96a by fitting a conductive terminal member or forming a conductive film (for example, a metal film). One end of the cable 93 and the stem pin S are connected to the connection terminals 96a, respectively.

As a result, the connection terminal 96a electrically connects the cable 93 and the stem portion 115 to each other. As described above, the groove portion 96g is formed in the region between the connection terminals 96a in the plate-shaped portion 96, and the insulation between the connection terminals 96a is secured. The plate-shaped portion 97 is arranged on an electrical connection portion (not shown) provided on the insulating block 81 in a state where the other ends of the cable 93 are connected, so that the cable 93 is electrically connected to the booster portion 82. Is connected to. That is, the wiring portion 91 functions as a socket for electrically connecting the X-ray tube 1 and the power supply unit 80, and the plate-shaped portion 96 and the plate-shaped portion 97 each function as the stem portion 115 (stem pin S) of the X-ray tube 1. ) And the electrical connection portion of the power supply unit 80 so as to be detachably fitted.

The tubular member 92 surrounds the wiring portion 91 by accommodating the wiring portion 91 inside. The tubular member 92 also functions as an electrode to which a high voltage voltage V is applied by being electrically connected to, for example, the boosting unit 82. Specifically, a high-voltage voltage V equal to or close to any high-voltage voltage V supplied to the cable 93 is applied, and in the present embodiment, the high-voltage voltage is equal to the potential of the cover electrode 117. V is applied. The tubular member 92 is a cylindrical metal member, and has a fixed diameter portion 92a having a substantially constant diameter along the height direction and an expansion in diameter that increases as the distance from the fixed diameter portion 92a along the height direction increases. Includes a diameter portion 92b. The fixed diameter portion 92a is located on the stem portion 115 side, and the enlarged diameter portion 92b is located on the insulating block 81 side.

Like the tubular member 92, the tubular member 92 is attached to the insulating block 81 via a mounting member 120 made of a metal material (for example, stainless steel, aluminum, etc.). The mounting member 120 includes a cylindrical first portion 121 having a first outer diameter, a cylindrical second portion 122 having a second outer diameter larger than the first outer diameter, and a first portion 121 to a second portion. It consists of a disc-shaped third portion 123 extending to reach 122. The first outer diameter is a diameter corresponding to the inner diameter of the enlarged diameter portion 92b of the tubular member 92, and a thread is formed on the outer surface of the first portion 121. As a result, the enlarged diameter portion 92b of the tubular member 92 is screwed and fixed to the first portion 121.

Further, the entire internal space of the high-voltage power feeding portion 90 and the mounting member 120 is filled with the insulating oil 71, and the wiring portion 91 is also immersed in the insulating oil 71. The insulating oil 71 flows in through, for example, a gap between the tubular member 92, the plate-shaped portion 96, and the stem portion 115. If even a small amount of air (air bubbles) remains in the accommodating portion H, the withstand voltage capacity is likely to decrease. Therefore, when the insulating oil 71 is used to seal the mixture, an area where air does not easily escape, for example, the mounting member 120 It is necessary to exhaust the air in the region between the insulation block 81 and the insulation block 81. Therefore, in the third portion 123, in addition to the screw hole 123r for attaching the mounting member 120 to the insulating block 81, a relief for releasing air when the mounting member 120 is mounted on the insulating block 81 and sealed with the insulating oil 71 is provided. Holes 123h and are formed. The bottom portion 92c of the tubular member 92 does not come into contact with the third portion 123, and forms a gap 92s with the third portion 123. Therefore, the air released from the relief hole 123h can be discharged through the gap 92s. Further, the screw hole 123r and the relief hole 123h are arranged on the lower side of the enlarged diameter portion 92b of the tubular member 92 (position facing the bottom portion 92c of the tubular member 92). As a result, the disturbance of the electric field due to the screw hole 123r and the relief hole 123h is suppressed.

As described above, in the X-ray generator 100, the stem portion 115 used for the electrical connection of the X-ray tube 1 is held in the vacuum housing 10 (insulation valve 2) of the X-ray tube 1. There is. A high-voltage voltage V is supplied to the X-ray tube 1 by a high-voltage power supply unit 90 extending from the power supply unit 80 toward the stem unit 115. The vacuum housing 10 (insulation valve 2) is formed with a wall portion 2a protruding toward the power supply unit 80 (insulation block 81) so as to surround the tip 90t of the high voltage power supply unit 90, and the power supply unit 80 (insulation). The block 81) is formed with a wall portion 83 made of an insulating material so as to surround the base end portion 90b of the high-voltage power feeding portion 90.

Then, in the X-ray generator 100, the high-voltage power feeding unit 90 includes an intermediate portion 90m exposed from the wall portion 2a and the wall portion 83 between the tip end portion 90t and the base end portion 90b. In other words, the wall portion 2a and the wall portion 83 are separated from each other in the height direction by the amount of the intermediate portion 90 m. As a result, the retention of the insulating oil 71 in the region between the wall portion 2a and the wall portion 83 is suppressed. Therefore, the heat dissipation efficiency of the insulating oil 71 can be improved.

Further, in the X-ray generator 100, the high-voltage power feeding unit 90 includes a wiring unit 91 for electrically connecting the boosting unit 82 and the stem unit 115, and a tubular member made of a metal material and surrounding the wiring unit 91. 92 and. Therefore, the wiring portion 91 is protected by the tubular member 92. In particular, since the tubular member 92 used to protect the wiring portion 91 is made of a metal material, the insulating oil 71 is used as compared with the case where the tubular member 92 is made of a resin material, for example. The heat dissipation efficiency can be further improved.

Further, in the X-ray generator 100, a voltage corresponding to the high voltage voltage V is applied to the tubular member 92. Therefore, the discharge is suppressed by stabilizing the electric field around the wiring portion 91 to which the high voltage voltage V is applied. Further, in the present embodiment, the cover electrode 117 having the same voltage (same potential) as the tubular member 92, together with the stem portion 115, is connected to the stem portion 115 at least at the tip portion 90t of the high-voltage power feeding portion 90. Since the periphery is surrounded, the electric potential around the connection portion with the stem portion 115 can be more stabilized. Therefore, the discharge is further suppressed. Further, by generating an electric field in the insulating oil 71 around the tubular member 92, the convection of the insulating oil 71 can be promoted and the heat dissipation efficiency can be further improved.

Further, in the X-ray generator 100, the wiring unit 91 includes a plurality of cables 93 electrically connected to the booster unit 82 and the stem unit 115, a base unit 94 made of an insulating material and supporting the cable 93, and the like. Includes. Therefore, the base portion 94 can be used to stably extend the cable 93 which is the supply path of the high voltage voltage V.

Further, in the X-ray generator 100, the base portion 94 includes a columnar portion 95 along the cable 93 and a plate-shaped portion 96 provided at the end portion of the columnar portion 95 on the stem portion 115 side. The plate-shaped portion 96 is provided with a plurality of connection terminals 96a for electrically connecting the cable 93 and the stem portion 115, and a groove portion is provided in the region between the connection terminals 96a in the plate-shaped portion 96. 96 g is formed. Therefore, the withstand voltage capability between the connection terminals 96a is improved. As a result, the high voltage V can be stably supplied.

Further, in the X-ray generator 100, the stem portion 115 is electrically connected to the electron gun 110, and the electron gun 110 has a cathode 112 that functions as an electron emitting unit and electrons constituting the electron beam B from the cathode 112. An electron arranged between the cathode 112 and the second grid electrode 114 and controlling the amount of electrons drawn from the cathode 112 and the second grid electrode 114 which also functions as a pull-out electrode for forming an electric field for pulling out the electron. It includes a first grid electrode 113 that functions as a quantity control electrode. In this way, the high-voltage voltage V is stably supplied to the electron gun 110 having the extraction electrode and the electron amount control electrode that require control by a voltage difference (within the predetermined range L described above) that is smaller than the high-voltage voltage V. It is possible.

The above-described embodiment describes one embodiment of the X-ray generator according to the present invention. Therefore, the X-ray generator according to the present invention is not limited to the above-mentioned X-ray generator 100. The X-ray generator according to the present invention may be an arbitrary modification of the above-mentioned X-ray generator 100 as long as the gist of each claim is not changed.

For example, the length of the intermediate portion 90m in the height direction is at least outside the high-pressure feeding portion 90 in a direction intersecting (orthogonal) in the extending direction of the high-pressure feeding portion 90 (the direction of the X-ray tube 1). The diameter S2 of the recess 116 in a direction larger than the distance S1 between the wall surface and the recess 116, more preferably in a direction intersecting (orthogonal) in the extending rubbing direction (tube axis direction of the X-ray tube 1) of the high-pressure feeding portion 90. It is 0.5 times or more and 5 times or less of.

Further, the wall portion 83 is not limited to the one integrated with the insulating block 81, and the wall portion 83 may be formed of an insulating member different from the insulating block 81. Further, the second wall portion formed in the power supply portion 80 is not limited to a structure such as the wall portion 83 in which a plate-like structure protruding toward the stem portion 115 is erected, and for example, an insulating block 81 may be used. The wall surface of the recess may be the second wall portion by providing the high-voltage power feeding portion 90 and the electrical connection portion on the bottom surface of the recess formed so as to be dug down. The insulating material constituting the insulating block 81 is not limited to the insulating resin, and for example, an insulating material other than the resin such as ceramic may be used. Further, the high-voltage voltage V is supplied not only to the electron gun 110 but also to the target T, and is not limited to the transmissive X-ray tube but a reflective X-ray tube using a reflective target. You may use it.

1 ... X-ray tube, 2 ... Insulated valve, 2a ... Wall part (first wall part), 10 ... Vacuum housing, 80 ... Power supply part, 81 ... Insulated block, 82 ... Boosting part, 83 ... Wall part (2nd) Wall part), 90 ... High-voltage power supply part (power supply part), 90t ... Tip part, 90b ... Base end part, 90m ... Intermediate part, 91 ... Wiring part, 92 ... Cylindrical member, 93 ... Cable, 94 ... Base part, 95 ... Columnar part, 96 ... Plate-shaped part, 96a ... Connection terminal, 96g ... Groove part, 110 ... Electron gun, 112 ... Cathode (electron emission part), 113 ... First grid electrode (electron amount control electrode), 114 ... 2 grid electrode (drawing electrode), 115 ... stem part (connection part), B ... electron beam, T ... target, X ... X-ray.

Claims (5)

An X-ray generator including an electron gun that generates an electron beam and a target that generates X-rays due to the incident of the electron beam, a vacuum housing that houses the X-ray generator, and the vacuum housing that is held in the vacuum housing. An X-ray tube having a connection part used for electrical connection of the X-ray generation part, and
A power supply unit having an insulating block that seals the booster unit that generates high voltage with an insulating material,
A power supply unit extending from the power supply unit toward the connection unit and supplying the high voltage voltage to the X-ray tube via the connection unit.
It includes at least a part of the X-ray tube including the connection part, the power supply part, and a storage part for accommodating a part of the power supply part in the insulating oil.
A first wall portion protruding toward the power supply unit is formed in a part of the X-ray tube so as to surround the tip end portion of the power supply unit on the connection portion side.
A second wall portion made of an insulating material is formed in a part of the power supply unit so as to surround the base end portion of the power supply unit on the power supply unit side.
The feeding portion is a portion between the tip and the base end portion, viewed including the intermediate portion exposed from the first wall portion and the second wall portion,
The feeding portion includes a wiring portion for electrically connecting the boosting portion and the connecting portion, and a tubular member made of a metal material and surrounding the wiring portion.
X-ray generator. The high voltage is applied to the tubular member.
The X-ray generator according to claim 1. The wiring portion includes a plurality of cables electrically connected to the booster portion and the connection portion, and a base portion made of an insulating material and supporting the cable.
The X-ray generator according to claim 1 or 2. The base portion includes a columnar portion along the cable and a plate-shaped portion provided at an end portion of the columnar portion on the connecting portion side.
The plate-shaped portion is provided with a plurality of connection terminals for electrically connecting the cable and the connection portion.
A groove is formed in the region between the connection terminals in the plate-shaped portion.
The X-ray generator according to claim 3. The connection is electrically connected to the electron gun and
The electron gun is arranged between an electron emitting section, a drawing electrode for forming an electric field for drawing electrons constituting the electron beam from the electron emitting section, and the electron emitting section and the drawing electrode. Includes an electron amount control electrode that controls the amount of electrons drawn from the electron emitting unit.
The X-ray generator according to any one of claims 1 to 4.

Images