JP6807998B1 - Manufacturing method of X-ray generator, power supply device, and X-ray generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray generator, a power supply device, and a method for manufacturing an X-ray generator capable of suppressing the occurrence of dielectric breakdown starting from a secondary coil of an isolation transformer. An X-ray generator 1 includes a power supply unit 7 that applies a voltage to an electron gun. The power supply unit 7 includes a first control unit, a booster unit 72, a primary coil 81 electrically connected to the first control unit, a secondary coil 82 electrically connected to the booster unit 72, and two. It has insulating transformers 8A and 8B including a support member 85 for supporting the next coil 82, and a sealing member 75 for sealing the step-up portion 72 and the insulating transformers 8A and 8B. The support member 85 is made of a first insulating resin material, and the sealing member 75 is made of a second insulating resin material. The absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material is 25% or less of the relative permittivity of the second insulating resin material. [Selection diagram] Fig. 2

Description

The present invention relates to an X-ray generator, a power supply device, and a method for manufacturing the X-ray generator.

Patent Document 1 describes an industrial X-ray generator including a cathode that emits electrons, an anode that generates X-rays when electrons collide with each other, and a high-voltage power supply unit that applies a high voltage to the cathode. ing.

Japanese Patent No. 5780644

In the power supply unit included in the X generator, a component having a high voltage may be sealed by a sealing member made of an insulating resin material. However, even when the material is sealed with an insulating resin material, the power supply unit may be damaged as a result of electric discharge due to dielectric breakdown in the power supply unit. As a result of diligent research by the present inventors, it has been confirmed that among the parts having a high voltage, there is a high possibility that dielectric breakdown occurs especially starting from the secondary coil of the isolation transformer.

An object of the present invention is to provide an X-ray generator, a power supply device, and a method for manufacturing an X-ray generator capable of suppressing the occurrence of dielectric breakdown starting from a secondary coil of an isolation transformer.

The X-ray generator of the present invention includes an electron gun that emits an electron beam, a target that emits X-rays when the electron beam is incident, and a power supply unit that applies a voltage to the electron gun. , The first control unit, the booster unit that boosts the voltage supplied from the first control unit, the primary side coil that is electrically connected to the first control unit, and the secondary side that is electrically connected to the booster unit. An insulating transformer that includes a coil and a support member that supports the secondary coil, a booster unit that is electrically connected to the electronic gun, and a power supply unit that applies a voltage boosted by the insulating transformer to the electronic gun, a booster unit, and a booster unit. It has a sealing member for sealing an insulating transformer, the support member is made of a first insulating resin material, and the sealing member is made of a second insulating resin material, and has a relative dielectric constant of the first insulating resin material. The absolute value of the difference from the relative dielectric constant of the second insulating resin material is 25% or less of the relative dielectric constant of the second insulating resin material.

In this X-ray generator, in the power supply unit, the secondary coil of the isolation transformer is supported by the support member made of the first insulating resin material, and the booster part and the isolation transformer are supported by the sealing member made of the second insulating resin material. Is sealed. In these first insulating resin material and second insulating resin material, the absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material is the relative permittivity of the second insulating resin material. It has a relationship of 25% or less of. As a result, it is possible to prevent dielectric breakdown from occurring from the secondary side coil via the support member. Therefore, according to this X-ray generator, it is possible to suppress the occurrence of dielectric breakdown starting from the secondary coil of the isolation transformer.

In the X-ray generator of the present invention, the insulating transformer further includes a bobbin around which a secondary coil is wound, and the bobbin is made of a third insulating resin material, and the relative permittivity of the first insulating resin material and the second insulation The absolute value of the difference from the relative permittivity of the resin material may be smaller than the absolute value of the difference between the relative permittivity of the second insulating resin material and the relative permittivity of the third insulating resin material. As a result, the absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material becomes the relative permittivity of the second insulating resin material and the relative permittivity of the third insulating resin material. As compared with the case where the difference is greater than or equal to the absolute value of, it is possible to more reliably suppress the occurrence of dielectric breakdown from the secondary coil via the support member.

In the X-ray generator of the present invention, the power supply unit further includes a booster unit and a second control unit that supplies a voltage boosted by an isolation transformer to the power supply unit, and the second control unit is made of a fourth insulating resin material. The sealing member seals the booster, the isolation transformer, and the second control unit, and the difference between the relative dielectric constant of the first insulating resin material and the specific dielectric constant of the second insulating resin material. The absolute value may be smaller than the absolute value of the difference between the specific dielectric constant of the second insulating resin material and the specific dielectric constant of the fourth insulating resin material. As a result, the absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material becomes the relative permittivity of the second insulating resin material and the relative permittivity of the fourth insulating resin material. As compared with the case where the difference is greater than or equal to the absolute value of, it is possible to more reliably suppress the occurrence of dielectric breakdown from the secondary coil via the support member.

In the X-ray generator of the present invention, the first insulating resin material and the second insulating resin material may be the same material. As a result, it is possible to more reliably suppress the occurrence of dielectric breakdown from the secondary side coil via the support member.

In the X-ray generator of the present invention, the support member may be a columnar member that supports the secondary coil. By using a columnar member as the support member, it is possible to facilitate the manufacture of the power supply unit.

In the X-ray generator of the present invention, the support member may support the secondary coil by sealing the primary coil and the secondary coil. As a result, since the secondary coil is covered with the first insulating resin material, it is possible to prevent dielectric breakdown from occurring from the secondary coil via the support member.

The power supply device of the present invention is a power supply device used for an electron gun that emits an electron beam and an X-ray generator including a target that emits X-rays when the electron beam is incident, and applies a voltage to the electron gun. The first control unit, the booster unit that boosts the voltage supplied from the first control unit, the primary side coil that is electrically connected to the first control unit, and the secondary unit that is electrically connected to the booster unit. An insulating transformer that includes a side coil and a support member that supports the secondary side coil, a booster unit that is electrically connected to the electronic gun, and a power supply unit that applies a voltage boosted by the insulating transformer to the electronic gun, and a booster unit. And a sealing member for sealing the insulating transformer, the support member is made of the first insulating resin material, and the sealing member is made of the second insulating resin material, and the relative dielectric constant of the first insulating resin material. The absolute value of the difference from the relative dielectric constant of the second insulating resin material is 25% or less of the relative dielectric constant of the second insulating resin material.

According to this power supply device, it is possible to suppress the occurrence of dielectric breakdown starting from the secondary coil of the isolation transformer for the same reason as the X-ray generator.

The method for manufacturing the X-ray generator of the present invention is the above-mentioned method for manufacturing the X-ray generator, in which the first step of forming an isolation transformer by supporting the secondary coil by a support member and the sealing member. A second step of sealing the booster and the isolation transformer is provided.

According to this method of manufacturing an X-ray generator, it is possible to obtain the X-ray generator in which the occurrence of dielectric breakdown is suppressed starting from the secondary coil of the isolation transformer.

In the method for manufacturing the X-ray generator of the present invention, in the first step, the secondary side coil is supported by the support member by attaching the secondary side coil to the support member which is a columnar member made of the first insulating resin material. Then, in the second step, the booster and the isolation transformer are arranged in the molding die, the second insulating resin agent made of the second insulating resin material is poured into the molding die, and the second insulating resin agent is cured. , The booster and the isolation transformer may be sealed by the sealing member. By using a columnar member as the support member, the first step can be facilitated.

In the method for manufacturing the X-ray generator of the present invention, in the first step, the primary side coil and the secondary side coil are arranged in the first molding mold, and the first insulating resin agent made of the first insulating resin material is first. The secondary coil is supported by the support member by pouring it into the 1 mold and curing the 1st insulating resin agent, and in the 2nd step, the booster and the isolation transformer are arranged in the 2nd mold. The booster portion and the isolation transformer may be sealed by pouring a second insulating resin agent made of a second insulating resin material into the second molding mold and curing the second insulating resin agent. As a result, the secondary coil can be covered with the first insulating resin material constituting the support member.

According to the present invention, it is possible to provide an X-ray generator, a power supply device, and a method for manufacturing an X-ray generator capable of suppressing the occurrence of dielectric breakdown starting from the secondary coil of an isolation transformer.

It is sectional drawing of the X-ray generator of 1st Embodiment. It is a perspective view of a part of the power-source part shown in FIG. It is a block diagram of the power-source part shown in FIG. It is sectional drawing which shows one process of the manufacturing method of the power-source part shown in FIG. It is sectional drawing which shows one process of the manufacturing method of the power-source part shown in FIG. It is a perspective view of the power-source part of the 2nd Embodiment. It is sectional drawing which shows one process of the manufacturing method of the power-source part shown in FIG. It is sectional drawing which shows one process of the manufacturing method of the power-source part shown in FIG. It is sectional drawing which shows one process of the manufacturing method of the power-source part shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding parts are designated by the same reference numerals, and overlapping parts are omitted.
[First Embodiment]
[Configuration of X-ray generator]

As shown in FIG. 1, the X-ray generator 1 includes an electron gun 2, a target unit 3, a housing 4, an exhaust pipe 6, and a power supply unit 7. The electron gun 2 emits an electron beam. At the tip of the target unit 3, a target 31 that emits X-rays when an electron beam is incident is provided. As an example, the target 31 is made of tungsten and has a disc shape. The housing 4 defines a passage 40 through which the electron beam and X-rays pass, and keeps the passage 40 in a vacuumed state. The housing 4 has a window portion 5. The window portion 5 allows the X-rays emitted from the target 31 to pass through the passage 40 to the outside. The exhaust pipe 6 is provided in the housing 4. A vacuum pump (not shown) is connected to the exhaust pipe 6. The power supply unit 7 applies a voltage to the electron gun 2 fixed to the tip (one end side) of the power supply unit 74, which will be described later.

In addition to the window portion 5, the housing 4 has a lower tubular portion 41, an upper tubular portion 42, and a head portion 43. As an example, the lower tubular portion 41 and the upper tubular portion 42 are each made of stainless steel and have a cylindrical shape. A power supply unit 7 is attached to the lower end of the lower tubular portion 41. The lower tubular portion 41 accommodates the electron gun 2 erected on the power supply portion 7. An exhaust pipe 6 is provided on the side wall of the lower tubular portion 41. The upper tubular portion 42 is erected on the upper end portion of the lower tubular portion 41 via the hinge portion 4a. By tilting the upper tubular portion 42 with respect to the lower tubular portion 41, the filament or the like provided in the electron gun 2 can be replaced from the upper opening of the lower tubular portion 41. A plurality of coil portions 49 are provided inside the upper tubular portion 42. The plurality of coil portions 49 function as electromagnetic deflection lenses, and focus the electron beam traveling in the passage 40 from the electron gun 2 toward the target 31 on the target 31.

The head portion 43 is provided on the upper end portion of the upper tubular portion 42. The head portion 43 is formed with a target insertion portion 48 that communicates the outside with the passage 40. The target unit 3 is inserted into the target insertion unit 48. The target portion 3 is removable from the head portion 43. The target 31 is exposed to the passage 40 in a state of being inclined so as to face each of the electron gun 2 and the window portion 5. In the passage 40, the portion where the electron gun 2 and the target 31 face each other is the electron beam passage 40a, and the portion where the target 31 and the window portion 5 face each other is the X-ray passage 40b. The electron beam passage 40a is formed in the lower tubular portion 41, the upper tubular portion 42, and the head portion 43. The X-ray passage 40b is formed in the head portion 43. The electron beam passage 40a and the X-ray passage 40b are connected at the head portion 43. A plurality of O-rings 32 are provided on the side surface of the target portion 3. As a result, the space between the target portion 3 and the target insertion portion 48 is airtightly sealed.

In the X-ray generator 1, a voltage is applied to the electron gun 2 by the power supply unit 7 in a state where the passage 40 is evacuated through the exhaust pipe 6 by the vacuum pump, and electrons are applied from the electron gun 2 to the electron beam passage 40a. When the beam is emitted, the electron beam is focused on the target 31 by the plurality of coil portions 49. When the electron beam is incident on the target 31 and X-rays are emitted from the target 31 into the X-ray passage 40b, the X-rays pass through the window portion 5 and are emitted to the outside.
[Power supply configuration]

As shown in FIGS. 2 and 3, the power supply unit 7 is sealed with a first control unit 71, a booster unit 72, a plurality of isolation transformers 8A and 8B, a second control unit 73, and a power supply unit 74. It has a stop member 75, a high-voltage transformer 76, and a case 77.

The first control unit 71 is electrically connected to an external PC (Personal Computer) or the like. The first control unit 71 controls the output voltage and the like of the power supply unit 7 according to the instruction transmitted from the PC or the like.

The boosting unit 72 is a cockcroft that boosts the voltage supplied from the first control unit 71. The booster portion 72 is electrically connected to the high voltage transformer 76. The high-voltage transformer 76 is electrically connected to the first control unit 71, and boosts the AC voltage supplied from the first control unit 71. The boosting unit 72 further boosts the voltage boosted by the high-voltage transformer 76. In the booster unit 72, the voltage that was alternating current at the time of boosting is converted to direct current.

The isolation transformer 8A applies a voltage to the Wenert electrode 21 of the electron gun 2. The isolation transformer 8B applies a voltage to the thermal cathode 22 of the electron gun 2. Since the configuration of the isolation transformer 8B is the same as the configuration of the isolation transformer 8A, the configuration of the isolation transformer 8A will be described below, and the description of the configuration of the isolation transformer 8B will be omitted. The isolation transformer 8A includes a primary coil 81, a secondary coil 82, an iron core 83, a bobbin 84, and a support member 85. The primary coil 81 is electrically connected to the first control unit 71. The secondary coil 82 is electrically connected to the booster 72. As an example, the iron core 83 is made of ferrite and has a square frame shape. At least the first side portion 83a of the iron core 83 is made of an insulating material. The first side portion 83a is fixed to the support plate 86 having a ground potential. A primary coil 81 is wound around the second side 83b of the iron core 83 opposite to the first side 83a. The primary coil 81 and the iron core 83 are covered with a cover (not shown) made of an insulating material.

The bobbin 84 is made of a third insulating resin material and has, for example, an annular shape. The secondary coil 82 is wound around the outer peripheral surface of the bobbin 84 along the circumferential direction of the bobbin 84. The support member 85 is a columnar member that supports the secondary coil 82, and is made of a first insulating resin material. The support member 85 has a shape in which the withstand voltage capability is improved by increasing the creepage distance at the time of discharge by extending, for example, a plate-shaped member made of the first insulating resin material in a zigzag shape. One end side of the support member 85 is fixed to the support plate 86. A bobbin 84 around which a secondary coil 82 is wound is attached to the other end side of the support member 85 by a bolt made of an insulating material (for example, the same material as the bobbin 84, the support member 85, etc.). The support member 85 supports the secondary coil 82 by supporting the bobbin 84 so that the second side portion 83b of the iron core 83 passes through the inner center of the bobbin 84.

The second control unit 73 converts the voltage boosted by the isolation transformers 8A and 8B into direct current, and supplies the converted voltage and the voltage boosted by the booster unit 72 to the feeding unit 74. The second control unit 73 includes the substrate 73a. The substrate 73a is a circuit board on which electronic components are mounted. The substrate 73a is made of a fourth insulating resin material.

In the power feeding portion 74, the electron gun 2 is fixed at the tip end portion (one end side), and is fixed to the sealing member at the base end portion (other end side). The power feeding unit 74 has a tubular shape and is made of an insulating material. The power feeding unit 74 encloses a power feeding wiring (not shown) in which the voltage boosted by the boosting unit 72 and the isolation transformers 8A and 8B is applied to the electron gun 2 via the second control unit 73 (not shown). The insulating material constituting the power feeding unit 74 may be the same as the material of the sealing member 75, or may be different from the material of the sealing member 75. Further, when the insulating material of the feeding portion 74 is the same as the material of the sealing member 75, the feeding portion 74 and the sealing member 75 may be integrally molded, or the feeding portion 74 and the sealing member 75 may be integrally molded. Each may be formed into a separate body and then joined.

Here, an example of applying a voltage to the electron gun 2 by the power supply unit 7 will be described in detail. As shown in FIG. 3, the high-voltage transformer 76 boosts an AC voltage signal of up to about 100 V supplied from the first control unit 71 from −s to several kV to −10s kV. The boosting unit 72 further boosts the voltage signal boosted by the high-voltage transformer 76 to −several hundred kV. In addition, the voltage signal that was alternating current at the time of boosting is converted to direct current. The isolation transformers 8A and 8B apply, for example, a maximum of -1500 V to the Wenert electrode 21 on the reference potential based on the voltage (-several hundred kV) boosted by the booster unit 72 via the second control unit 73 and the power supply unit 74. Apply. Further, the isolation transformers 8A and 8B are placed on the thermal cathode 22 via the second control unit 73 and the feeding unit 74, for example, on the reference potential based on the voltage (-several hundred kV) boosted by the booster unit 72. Apply V. In FIG. 3, the portion of the power supply unit 7 that has a high voltage is indicated by a thick line.

The sealing member 75 seals the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73. Further, in the support plate 86, at least the surface on the side facing the secondary coil 82 is sealed by the sealing member 75. The sealing member 75 is made of a second insulating resin material and has, for example, a substantially rectangular parallelepiped shape. The sealing member 75 has a function of maintaining electrical insulation of the boosting unit 72, the isolation transformers 8A and 8B, and the second control unit 73, which have a high voltage. The first control unit 71 and the high-voltage transformer 76 are provided outside the sealing member 75 in the power supply unit 7. Further, the sealing member 75 is housed in the case 77 as shown in FIG. As an example, the case 77 is an outer housing of the power supply unit 7 made of a metal material, and has a rectangular box shape.

Here, the first insulating resin material constituting the support member 85 (hereinafter, simply referred to as “material of the support member 85”) and the second insulating resin material constituting the sealing member 75 (hereinafter, simply “the material of the sealing member 75”). Material), a third insulating resin material constituting the bobbin 84 (hereinafter, simply referred to as “material of bobbin 84”), and a fourth insulating resin material constituting the substrate 73a of the second control unit 73 (hereinafter, simply referred to as “material”). The relationship of "material of the substrate 73a") will be described. The relative permittivity in this embodiment is a value obtained by dividing the permittivity of the target substance by the permittivity of vacuum.

The absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is 25% or less of the relative permittivity of the material of the sealing member 75. In other words, the relative permittivity of the material of the support member 85 is included in the range of 75% or more and 125% or less of the relative permittivity of the material of the sealing member 75. Specifically, for example, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 may be 0 or more and 1.0 or less. The absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the bobbin 84. Is less than the absolute value of the difference. Further, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the substrate 73a. Is less than the absolute value of the difference. The absolute value of the difference between the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 is 1 × 10 ¹⁵ [Ω · m] or less. The absolute value of the difference between the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 is the volume resistivity of the material of the sealing member 75 and the volume resistivity of the material of the bobbin 84. Is less than the absolute value of the difference. Further, the absolute value of the difference between the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 is the volume resistivity of the material of the sealing member 75 and the volume resistivity of the material of the substrate 73a. Is less than the absolute value of the difference.

In the present embodiment, the material of the support member 85 and the material of the sealing member 75 are the same materials, for example, epoxy resin. That is, in the present embodiment, the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 are equal to each other. Further, the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 are equal to each other. The material of the bobbin 84 is, for example, PEEK, and the material of the substrate 73a is, for example, a glass epoxy resin.
[Manufacturing method of power supply]

First, as shown in FIG. 4, the isolation transformers 8A and 8B are configured by supporting the secondary coil 82 by the support member 85 (first step). Specifically, first, a primary coil 81, a secondary coil 82, an iron core 83, and a bobbin 84 are prepared. An iron core 83 is passed through the hole of the bobbin 84, and the first side portion 83a of the iron core 83 is fixed to the support plate 86. Next, one end side of the support member 85 is fixed to the support plate 86, and the bobbin 84 around which the secondary coil 82 is wound is fixed to the other end side of the support member 85. As a result, the secondary coil 82 is supported by the support member 85, and the isolation transformers 8A and 8B are configured.

Subsequently, as shown in FIG. 5, the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73 are sealed by the sealing member 75 (second step). Specifically, first, the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73 are arranged in the mold M. Next, the second insulating resin agent r2 made of the second insulating resin material is poured into the mold M to cure the second insulating resin agent r2. As a result, the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73 are sealed by the sealing member 75, and the power supply unit 7 shown in FIG. 2 is obtained.
[Action and effect]

In the X-ray generator 1, in the power supply unit 7, the secondary side coils 82 of the isolation transformers 8A and 8B are supported by the support member 85, and the booster unit 72 and the isolation transformers 8A and 8B are sealed by the sealing member 75. Has been done. The absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is 25% or less of the relative permittivity of the material of the sealing member 75. As a result, it is possible to prevent dielectric breakdown from occurring from the secondary coil 82 via the support member 85. Therefore, according to the X-ray generator 1, it is possible to suppress the occurrence of dielectric breakdown starting from the secondary coil 82 of the isolation transformers 8A and 8B. In particular, when the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is 0 or more and 1.0 or less, the support member 85 is removed from the secondary coil 82. It is possible to further suppress the occurrence of dielectric breakdown. In order to suppress dielectric breakdown from the secondary coil 82 via the support member 85, the absolute value of the difference between the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 is 1 ×. It is particularly effective when it is 10 ¹⁵ [Ω · m] or less.

Here, a comparison with the conventional example will be described. For example, when the material of the conventional support member 85 is a commonly used glass epoxy resin, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is It is about 30% of the relative permittivity of the material of the sealing member 75. In that case, dielectric breakdown may occur from the secondary coil 82 via the support member 85. On the other hand, according to the X-ray generator 1, it is possible to suppress the occurrence of dielectric breakdown starting from the secondary coil 82 of the isolation transformers 8A and 8B. It should be noted that the suppression of the occurrence of dielectric breakdown starting from the secondary coil 82 is particularly effective when the voltage used in the power supply unit 7 is 100 kV or more in absolute value, and particularly 200 kV or more in absolute value. ..

Further, in the X-ray generator 1, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the bobbin 84. It is smaller than the absolute value of the difference from the relative permittivity of the material of. As a result, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the bobbin 84. Compared with the case where the difference is greater than or equal to the absolute value of, it is possible to more reliably suppress the occurrence of dielectric breakdown from the secondary side coil 82 via the support member 85. In order to suppress insulation failure from the secondary coil 82 to the support member 85, the absolute value of the difference between the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 is sealed. It is particularly effective when it is smaller than the absolute value of the difference between the volume resistivity of the material of the member 75 and the volume resistivity of the material of the bobbin 84.

For example, when the material of the conventional support member 85 is a commonly used glass epoxy resin, since the material of the bobbin 84 is PEEK, the relative permittivity of the material of the support member 85 and the ratio of the material of the sealing member 75 The absolute value of the difference from the dielectric constant is larger than the absolute value of the difference between the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the bobbin 84. In that case, dielectric breakdown may occur from the secondary coil 82 via the support member 85. According to the X-ray generator 1, it is possible to more reliably suppress the occurrence of such dielectric breakdown.

Further, in the X-ray generator 1, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the substrate 73a. It is smaller than the absolute value of the difference from the relative permittivity of the material of. As a result, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the substrate 73a. Compared with the case where the difference is greater than or equal to the absolute value of, it is possible to more reliably suppress the occurrence of dielectric breakdown from the secondary side coil 82 via the support member 85. In order to suppress insulation failure from the secondary coil 82 to the support member 85, the absolute value of the difference between the volume resistivity of the material of the support member 85 and the volume resistivity of the material of the sealing member 75 is sealed. It is particularly effective when it is smaller than the absolute value of the difference between the volume resistivity of the material of the member 75 and the volume resistivity of the material of the substrate 73a.

For example, when the material of the conventional support member 85 is the same glass epoxy resin as the material of the substrate 73a, the absolute value of the difference between the relative permittivity of the material of the support member 85 and the relative permittivity of the material of the sealing member 75. Is equal to the absolute value of the difference between the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the substrate 73a. In that case, dielectric breakdown may occur from the secondary coil 82 via the support member 85. According to the X-ray generator 1, it is possible to more reliably suppress the occurrence of such dielectric breakdown.

Further, in the X-ray generator 1, the material of the support member 85 and the material of the sealing member 75 are the same material. As a result, it is possible to more reliably suppress the occurrence of dielectric breakdown from the secondary coil 82 via the support member 85.

Further, in the X-ray generator 1, the support member 85 is a columnar member that supports the secondary coil 82. By using a columnar member as the support member 85, it is possible to facilitate the manufacture of the power supply unit 7. Further, even though the support member 85 is a columnar member erected inside the sealing member 75, it is possible to prevent dielectric breakdown from occurring from the secondary coil 82 via the support member 85.

Further, the manufacturing method of the X-ray generator 1 includes the first step of forming the isolation transformers 8A and 8B by supporting the secondary coil 82 by the support member 85, and the booster portion 72 and the insulation by the sealing member 75. A second step of sealing the transformers 8A and 8B is provided. According to the manufacturing method of the X-ray generator 1, it is possible to suppress the occurrence of dielectric breakdown starting from the secondary coil 82 of the isolation transformers 8A and 8B for the same reason as the X-ray generator 1.

In the manufacturing method of the X-ray generator 1, in the first step, the secondary side coil 82 is attached to the support member 85, which is a columnar member made of the first insulating resin material, and the secondary side coil is formed by the support member 85. Support 82. In the second step, the booster portion 72 and the isolation transformers 8A and 8B are arranged in the molding die M, the second insulating resin agent made of the second insulating resin material is poured into the molding die M, and the second insulating resin agent r2. The booster portion 72 and the isolation transformers 8A and 8B are sealed by the sealing member 75. By using a columnar member as the support member 85, the sealing member 75 can be used to properly support the secondary coil 82, so that the first step can be facilitated.
[Second Embodiment]
[Power supply configuration]

The X-ray generator 1 of the second embodiment is different in the configuration of the power supply unit 7 (specifically, the support member 87 of the isolation transformer 8A seals the primary coil 81 and the secondary coil 82. It is different from the X-ray generator 1 of the first embodiment in that it supports the secondary coil 82). Hereinafter, the differences from the first embodiment will be mainly described.

The isolation transformer 8A shown in FIG. 6 includes a primary coil 81, a secondary coil 82, an iron core 83, a bobbin 84, and a support member 87. The support member 87 is secondary by sealing the primary coil 81 and the secondary coil 82 so that the secondary coil 82 is fixed to the primary coil 81 at a predetermined distance. It supports the side coil 82. More specifically, in the support member 87, the second side portion 83b of the iron core 83 inserts the inner center of the bobbin 84, and the secondary coil 82 is separated from the primary coil 81 by a predetermined distance. The primary coil 81, the secondary coil 82, the iron core 83, and the bobbin 84 are sealed so that the secondary coil 82 is fixed in the support member 87 in such an arrangement relationship. ing. That is, regarding the support of the secondary side coil 82 of the second embodiment, the secondary side coil 82 is sealed by the support member 87 instead of having an upright member like the support member 85 of the first embodiment. Also serves as support. The support member 87 is made of a first insulating resin material (hereinafter, simply referred to as “material of the support member 87”), and has, for example, a rectangular parallelepiped shape. In the present embodiment, the material of the support member 87 and the material of the sealing member 75 are the same materials, for example, epoxy resin.

The sealing member 75 seals the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73. In the sealing of the isolation transformers 8A and 8B, the support member 87 that seals the primary coil 81, the secondary coil 82, the iron core 83, and the bobbin 84 is further sealed by the sealing member 75. ..
[Manufacturing method of power supply]

First, as shown in FIG. 7, the isolation transformers 8A and 8B are configured by supporting the secondary coil 82 by the support member 87 (first step). Specifically, first, the primary coil 81, the secondary coil 82, the iron core 83, the bobbin 84, and the support plate 86 are arranged in the first molding die M1. Here, the holder H for holding the secondary coil 82 and the bobbin 84 is fixed to the first molding die M1. The secondary coil 82 and the bobbin 84 are attached to the holder H, and the primary coil 81, the iron core 83 and the support plate 86 are arranged so that the second side portion 83b of the iron core 83 passes through the center of the bobbin 84. 1 It is fixed to the molding die M1. Next, the first insulating resin agent r1 made of the first insulating resin material is poured into the first molding mold M1 and the first insulating resin agent r1 is cured to support the secondary coil 82 by the support member 87. .. In this way, as shown in FIG. 8, the isolation transformer 8A in which the secondary coil 82 is supported by the support member 87 so that the secondary coil 82 is fixed in the support member 87 in a floating state. , 8B is configured. The holder H is removed from the support member 87 after the first insulating resin agent r1 is cured. Therefore, the support member 87 has a recess C in a portion corresponding to the holder H on the surface 87A on a predetermined side (upper side in FIG. 8). Further, the portion of the secondary coil 82 that was covered with the holder H is not sealed by the support member 87 (first insulating resin agent r1) and is exposed from the recess C.

Subsequently, as shown in FIG. 9, the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73 are sealed by the sealing member 75 (second step). Specifically, first, the booster unit 72, the isolation transformers 8A and 8B, and the second control unit 73 are arranged in the second molding mold M2. For the isolation transformers 8A and 8B, the support member 87 in which the primary side coil 81, the secondary side coil 82, the iron core 83, the bobbin 84 and the support plate 86 are sealed is arranged in the second molding die M2. .. At that time, the support member 87 is arranged so that the surface 87A having the recess C faces the inside (center side) of the second molding die M2. Next, the second insulating resin agent r2 made of the second insulating resin material is poured into the second molding mold M2, and the second insulating resin agent r2 is cured to cure the booster portion 72, the insulating transformers 8A and 8B, and the second. The control unit 73 is sealed. At that time, since the recess C is also sealed with the second insulating resin agent r2, the secondary coil 82 exposed from the recess C is also sealed. As a result, the power supply unit 7 shown in FIG. 6 is obtained.
[Action and effect]

The X-ray generator 1 can suppress the occurrence of dielectric breakdown starting from the secondary coil 82 of the isolation transformers 8A and 8B for the same reason as the X-ray generator 1 of the first embodiment. Further, in the X-ray generator 1, the support member 87 supports the secondary coil 82 by sealing the primary coil 81 and the secondary coil 82. As a result, since the secondary coil 82 is covered with the material of the support member 85, it is possible to prevent dielectric breakdown from occurring from the secondary coil 82 via the support member 85.

Further, according to the manufacturing method of the X-ray generator 1, dielectric breakdown starting from the secondary coil 82 of the isolation transformers 8A and 8B for the same reason as the manufacturing method of the X-ray generator 1 of the first embodiment. It is possible to obtain an X-ray generator 1 in which the generation of is suppressed.

Further, in the manufacturing method of the X-ray generator 1, in the first step, the primary side coil 81 and the secondary side coil 82 are arranged in the first molding mold M1, and the first insulating resin agent made of the first insulating resin material. The secondary coil 82 is supported by the support member 87 by pouring r1 into the first molding die M1 and curing the first insulating resin agent r1. In the second step, the step-up section 72 and the isolation transformers 8A and 8B are arranged in the second molding die M2, and the second insulating resin agent r2 made of the second insulating resin material is poured into the second molding die M2. 2 By curing the insulating resin agent r2, the booster portion 72 and the isolation transformers 8A and 8B are sealed. As a result, the secondary coil 82 can be covered with the first insulating resin material constituting the support member 85. In particular, in the second step, the support member 87 is arranged so that the surface 87A provided with the recess C faces the inside (center side) of the second molding die M2. As described above, the high voltage region in the power supply unit 7 (particularly, the region where the booster unit 72, the secondary coil 82 and the second control unit 73 are arranged), and the first insulating resin material and the second insulating resin in the high voltage region. By arranging the interface with the material inside (center side) of the support member 87, the withstand voltage capability can be improved and the occurrence of dielectric breakdown can be more reliably suppressed.
[Modification example]

The present invention is not limited to the embodiments described above. For example, in the materials of the support members 85 and 87 and the material of the sealing member 75, the absolute value of the difference between the relative permittivity of the material of the support members 85 and 87 and the relative permittivity of the material of the sealing member 75 is sealed. As long as it is 25% or less of the relative permittivity of the stopping member 75, it is not limited to the above. As an example, the materials of the support members 85 and 87 and the material of the sealing member 75 do not have to be the same material. Further, the absolute value of the difference between the relative permittivity of the materials of the support members 85 and 87 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the relative permittivity of the material of the bobbin 84. It may be greater than or equal to the absolute value of the difference from the rate. Further, the absolute value of the difference between the relative permittivity of the materials of the supporting members 85 and 87 and the relative permittivity of the material of the sealing member 75 is the relative permittivity of the material of the sealing member 75 and the material of the substrate 73a. It may be greater than or equal to the absolute value of the difference from the rate. Further, in the materials of the support members 85 and 87 and the material of the sealing member 75, the absolute value of the difference between the volume resistivity of the material of the support members 85 and 87 and the volume resistivity of the material of the sealing member 75 is 1. As long as it is x10 ¹⁵ [Ω · m] or less, it is not limited to the above. As an example, the materials of the support members 85 and 87 and the material of the sealing member 75 do not have to be the same material. Further, the absolute value of the difference between the volume resistivity of the materials of the support members 85 and 87 and the volume resistivity of the material of the sealing member 75 is the volume resistivity of the material of the sealing member 75 and the volume resistivity of the material of the bobbin 84. It may be greater than or equal to the absolute value of the difference from the rate. Further, the absolute value of the difference between the volume resistivity of the materials of the support members 85 and 87 and the volume resistivity of the material of the sealing member 75 is the volume resistivity of the material of the sealing member 75 and the volume resistivity of the material of the substrate 73a. It may be greater than or equal to the absolute value of the difference from the rate.

In the above-described embodiment, the support members 85 and 87 support the secondary coil 82 so that the primary coil 81 passes through the inside of the secondary coil 82. It may be configured to support the secondary coil 82. Further, the support member 85 of the first embodiment is not limited to a zigzag shape, and may be, for example, a linear columnar member, and may be a columnar, polygonal columnar, or the like, not limited to a plate shape. ..

The booster 72 is not limited to Cockcroft, and may be, for example, a booster circuit using a capacitor and a diode like Cockcroft, a Delon-Grinachel circuit, a Billard circuit, a Chimmelmann (or Witka) circuit, a Schenken multi-stage rectifier circuit, or the like. Good.

In the above-described embodiment, the configuration in which the power supply unit 7 has two isolation transformers 8A and 8B is illustrated, but the number of isolation transformers may be, for example, one or three or more. Further, by surrounding the secondary coil 82 with a cover made of an insulating material, the occurrence of dielectric breakdown starting from the secondary coil 82 may be further suppressed.

In the above-described embodiment, the X-ray generator 1 is a reflection type device in which the X-ray generated by the target 31 is emitted to the side where the electron beam is incident on the target 31, but the electron beam is emitted to the target 31. It may be a transmission type device in which X-rays generated by the target 31 are emitted on the side opposite to the incident side. Further, in the above-described embodiment, the X-ray generator 1 is an open type device capable of opening and closing the inside of the housing 4, but may be a vacuum sealed type device.

In the above-described embodiment, the power supply unit 7 is a component of the X-ray generator 1, but may be configured as a single power supply device, for example. Similar to the X-ray generator 1 of the first and second embodiments described above, the power supply device can also suppress the occurrence of dielectric breakdown starting from the secondary coil 82 of the isolation transformers 8A and 8B.

1 ... X-ray generator, 2 ... Electron gun, 7 ... Power supply unit, 8A, 8B ... Isolation transformer, 31 ... Target, 71 ... First control unit, 72 ... Booster unit, 73 ... Second control unit, 74 ... Power supply Part, 75 ... Sealing member, 81 ... Primary side coil, 82 ... Secondary side coil, 84 ... Bobbin, 85, 87 ... Support member, 73a ... Substrate, M ... Molding mold, M1 ... First molding mold, M2 ... 2nd molding mold, r1 ... 1st insulating resin agent, r2 ... 2nd insulating resin agent.

Claims (10)

An electron gun that emits an electron beam and
A target that emits X-rays when the electron beam is incident,
A power supply unit for applying a voltage to the electron gun is provided.
The power supply unit
1st control unit and
A booster that boosts the voltage supplied from the first control unit,
An isolation transformer including a primary coil electrically connected to the first control unit, a secondary coil electrically connected to the booster, and a support member for supporting the secondary coil.
A power supply unit that is electrically connected to the electron gun and applies a voltage boosted by the booster unit and the isolation transformer to the electron gun.
It has a booster and a sealing member that seals the isolation transformer.
The support member is made of a first insulating resin material.
The sealing member is made of a second insulating resin material.
The absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material is 25% or less of the relative permittivity of the second insulating resin material. .. The isolation transformer further includes a bobbin around which the secondary coil is wound.
The bobbin is made of a third insulating resin material.
The absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material is the relative permittivity of the second insulating resin material and the relative permittivity of the third insulating resin material. The X-ray generator according to claim 1, which is smaller than the absolute value of the difference between. The power supply unit further includes a booster unit and a second control unit that supplies a voltage boosted by the isolation transformer to the power supply unit.
The second control unit includes a substrate made of a fourth insulating resin material.
The sealing member seals the booster unit, the isolation transformer, and the second control unit.
The absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material is the relative permittivity of the second insulating resin material and the relative permittivity of the fourth insulating resin material. The X-ray generator according to claim 1 or 2, which is smaller than the absolute value of the difference from. The X-ray generator according to any one of claims 1 to 3, wherein the first insulating resin material and the second insulating resin material are the same material. The X-ray generator according to any one of claims 1 to 4, wherein the support member is a columnar member that supports the secondary coil. The X-ray generator according to any one of claims 1 to 4, wherein the support member supports the secondary coil by sealing the primary coil and the secondary coil. .. A power supply device used in an X-ray generator including an electron gun that emits an electron beam and a target that emits X-rays when the electron beam is incident, and applies a voltage to the electron gun.
1st control unit and
A booster that boosts the voltage supplied from the first control unit,
An isolation transformer including a primary coil electrically connected to the first control unit, a secondary coil electrically connected to the booster, and a support member for supporting the secondary coil.
A power supply unit that is electrically connected to the electron gun and applies a voltage boosted by the booster unit and the isolation transformer to the electron gun.
A sealing member for sealing the booster and the isolation transformer.
The support member is made of a first insulating resin material.
The sealing member is made of a second insulating resin material.
A power supply device in which the absolute value of the difference between the relative permittivity of the first insulating resin material and the relative permittivity of the second insulating resin material is 25% or less of the relative permittivity of the second insulating resin material. The method for manufacturing an X-ray generator according to claim 1.
The first step of forming the isolation transformer by supporting the secondary coil by the support member, and
A method for manufacturing an X-ray generator, comprising a second step of sealing the booster portion and the isolation transformer with the sealing member. In the first step, the secondary side coil is supported by the support member by attaching the secondary side coil to the support member which is a columnar member made of the first insulating resin material.
In the second step, the booster and the isolation transformer are arranged in the molding mold, the second insulating resin agent made of the second insulating resin material is poured into the molding mold, and the second insulating resin agent is used. The method for manufacturing an X-ray generator according to claim 8, wherein the booster and the isolation transformer are sealed by the sealing member by curing. In the first step, the primary coil and the secondary coil are arranged in the first molding mold, and the first insulating resin agent made of the first insulating resin material is poured into the first molding mold. By curing the first insulating resin agent, the secondary coil is supported by the support member.
In the second step, the booster and the isolation transformer are arranged in the second molding mold, and the second insulating resin agent made of the second insulating resin material is poured into the second molding mold, and the second molding is performed. The method for manufacturing an X-ray generator according to claim 8, wherein the booster and the isolation transformer are sealed by curing the insulating resin agent.

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