JP2001015294A - X-ray generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray generating device capable of certainly maintaining the optimum operating temp. of an X-ray tube even if the structure is such that the trunk of the X-ray tube is put inside a molding. SOLUTION: An X-ray generating device 1 is structured so as not to cool a target 5 directly but to cool a molded part 17 and cool the target 5 indirectly. To the molded part 17, a metal panel 19 is attached fast for enhancing the cooling efficiency, where the attachment is not made for a simple purpose but for the purpose of further enhancing the thermal conductivity between the molded part 17 and the panel 19. Tight attachment between the molded part 17 and an electric connector part 24 can also be enhanced by embedding the base 24A of the connector part 24 in the molded part 17, which prevents the connector part 24 from loosening or slipping off from the panel 19 in good workmanship. This type of connector 24 allows a high-voltage convertor unit to be provided separately, and the X-ray generating device 1 can be embodied in a lightweight compacted construction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an X-ray generator, and more particularly, to an X-ray generator for use as a microfocus X-ray source.

[0002]

2. Description of the Related Art Conventionally, techniques in such a field are disclosed in JP-A-6-162974, JP-A-6-84490, JP-A-6-36720 and JP-A-5-29.
No. 0768. The X-ray generators described in these publications disclose means for releasing high heat generated from an X-ray tube to the outside to maintain stable operation characteristics. Specifically, a cooling passage is formed in the target support body, and cooling water is passed through the passage to cool the target that is a heat source.

[0003]

However, the above-mentioned conventional X-ray generator has the following problems. That is, since a structure for cooling the target support is adopted, it is difficult to apply the method to a mold type X-ray tube. There is a problem that it is difficult to maintain the contact with the cooling medium and it is difficult to obtain a desired cooling efficiency.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and in particular, maintains an optimum operating temperature of an X-ray tube even when the body of the X-ray tube is housed in a mold portion. It is an object of the present invention to provide an X-ray generator that ensures the above.

[0005]

According to a first aspect of the present invention, there is provided an X-ray generating apparatus according to the present invention, wherein an electron emitted from an electron gun in a housing collides with a target, and the X-ray generated by the collision is converted into an X-ray. X having a structure for emitting light to the outside through an emission window
An X-ray tube, an electrically insulating mold portion surrounding and storing the body of the X-ray tube accommodating the target therein, a metal panel fixed to the mold portion, and an X-ray fixed to the panel. A base for electrically connecting to the target of the tube includes an electrical connector embedded in the mold.

In this X-ray generator, the target of the X-ray tube is housed in a body, which is charged to a high pressure and is stored in an electrically insulating mold part in consideration of electrical sealing. The target is difficult to cool. So instead of letting the target cool directly,
The target is indirectly cooled by cooling the mold portion. In this case, a metal panel for improving the cooling efficiency is fixed to the mold part. Further, by fixing the electrical connector portion to such a panel and embedding the base of the electrical connector portion in the mold portion, the adhesion between the mold portion and the electrical connector portion is improved, and the electrical connector portion is loosened or disconnected from the panel. Is properly prevented, and the panel is prevented from dropping from the mold portion. Such an electrical connector makes it possible to disconnect the high-voltage conversion unit from the X-ray generator,
Lightweight and compact are also achieved at the same time.

In the X-ray generator according to the present invention, it is preferable that the panel forms a part of a mold when the mold is molded. In this case, the metal panel for the purpose of improving the cooling efficiency is fixed to the mold part, but the metal panel is not simply fixed, but is intended to further improve the thermal conductivity between the mold part and the panel. It is used as a part of a mold frame at the time of molding of the mold portion to improve the adhesion between the mold portion and the panel.

The X-ray generator according to claim 3, wherein a metal front panel fixed to the mold portion, an electrically insulating oil storage portion formed by the mold portion, the housing of the X-ray tube, and the front panel; It is preferable to include a flange formed on the housing of the wire tube and fixedly in contact with the outer surface of the front panel. When such a configuration is adopted, the oil filled between the mold part and the X-ray tube becomes hot due to the influence of the target, but the metal front panel arranged at the end face of the mold part comes into contact with the oil. Therefore, heat radiation by the front panel can be promoted.

Preferably, the panel is a rear panel facing the front panel fixed to the mold portion. With this configuration,
The X-ray tube can be fixed using the front panel,
The electrical connector can be fixed using the rear panel, so that the heat radiation effect can be further enhanced by cooperation between the front panel and the rear panel, and the X-ray tube and the electrical connector are aligned in a line. X
It becomes easy to apply a high voltage to the target from behind the wire tube.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
One preferred embodiment of the line generator will be described in detail.

FIG. 1 is a perspective view showing an X-ray generator according to the present invention. The X-ray generator 1 shown in FIG. 1 accommodates the X-ray tube 3 in a metal case 2 and does not incorporate a high-voltage generator, thereby achieving compactness and light weight. . That is, a high-voltage conversion unit (not shown) in which a transformer, a high-voltage generation circuit, a control circuit, and the like, which are high heat generation sources, are incorporated and the X-ray generator 1 are separated from each other. Maintenance becomes easy, and even when the X-ray tube 3 is brought close to the sample, the influence of heat on the sample can be reduced, and the convenience is greatly improved.

As shown in FIG. 2, an X-ray tube 3 housed in a case 2 is configured as a microfocus X-ray tube used for nondestructive inspection and the like. And end-wind type, but this is end-wind type. The X-ray tube 3 contains an electron gun 4 that emits electrons and a target 5 that generates X-rays by collision of electrons as main components in a housing S.

The housing S is divided into a plurality of parts, extends in the lateral direction, and has a glass body 7 for accommodating the target 5.
And a metal electron gun housing 8 for housing the electron gun 4, and a metal head 9 for connecting the body 7 and the electron gun housing 8. That is, the electron gun accommodating section 8 stores the electron gun 4
The head part 9 and the body part 7 form a part of the housing S on the target 5 side, and each member 7, 8, 9
Are connected and fixed to each other to form one housing S.

A stem 11 made of ceramics is fitted on the top of the electron gun accommodating section 8, and the head 9
An X-ray emission window 14 is formed on the end face of the substrate so as to face the target 5. The electron gun 4 has a heater electrode 15
a, a cathode 15b, a grid electrode 15c, and a focus electrode 15d, and are fixed in the electron gun accommodating portion 8 via a support 15e. The tip of the target 5 is cut obliquely at about 25 °, and the target member 5b is brazed.

When the cathode electrode 15b is heated by the heater electrode 15a, the cathode electrode 1b is heated at a constant temperature.
Electrons are emitted from 5b. The emitted electrons are accelerated by the grid electrode 15c, converged by the focus electrode 15d, and collide with the target 5. The collision converts the electrons into X-rays and heat, and the generated X-rays
The light is emitted outside through the X-ray emission window 14.

As shown in FIG. 3, the body 7 of the X-ray tube 3 is accommodated in a rectangular parallelepiped mold portion 17 formed of an electrically insulating resin mold material.
The front panel 18 and the rear panel 1 made of metal (brass plated with nickel, chromium or copper, etc.)
9 is fixed. The front panel 18 is integrated with the mold part 17 by an adhesive or the like, and the rear panel 19
Is used as a mold frame during molding, and is integrally formed with the mold portion 17. Further, an opening 20 for inserting the body 7 of the X-ray tube 3 from the front panel 18 side is formed in the mold portion 17.

Further, the body 7 of the X-ray tube 3 is
When the X-ray tube 3 is fixed to the front panel 18 by inserting
A desired electrically insulating oil storage portion 21 is formed by the inner wall surface of the mold portion 17, the inner wall surface of the front panel 18, and the outer wall surface of the body portion 7. An electric insulating oil 22 is provided in the housing 21.
The oil 22 prevents the high voltage of the target 5 from being transmitted to the outside via the mold portion 17.

Then, the temperature of the oil 22 filled between the mold part 17 and the X-ray tube 3 becomes high due to the influence of the target 5. However, since the metal front panel 18 disposed on the end face of the mold portion 17 is brought into contact with the oil 22, the heat radiation effect of the oil 22 by the metal front panel 18 is enhanced. Further, in order to improve the heat radiation effect of the mold portion 17, the upper plate 26 is arranged so as to be in contact with the upper surface of the mold portion 17. It goes without saying that the back panel 19 also has the same heat radiation effect.

The X-ray tube 3 is fixed via screws 25 so that the flange 23 provided on the head 9 is brought into contact with the front panel 18 (see FIG. 2).
After the X-ray tube 3 is fixed to the front panel 18, filling is performed from a predetermined location. An electric connector 24 for inserting a plug P extending from a separate high-voltage conversion unit is fixed to the rear panel 19 so as to be tightened from the inside by a nut 27. The electric connector 24 is connected via a connecting portion 28. Connected to the rear end 5 a of the target 5.

Here, assuming that the mold portion 17 is cooled to indirectly cool the target 5, the front panel 1
8 and the rear panel 19 are adopted.
In order to further improve the heat conductivity and the electrical conductivity between the mold portion 17 and the panel 19, instead of simply fixing them to the mold portion 17, the metal panel 19 is used when the mold portion 17 is molded. Used as part of the formwork of
The adhesion between the mold part 17 and the panel 19 is improved.

Specifically, as shown in FIGS. 4 and 5,
In molding the rectangular parallelepiped mold portion 17 with resin, the side frames 50A, 50B, the bottom frame 50C, and the front frame 5 are formed.
0D and the back panel 19 define a rectangular parallelepiped cavity A whose upper part is open. In the cavity A, a core (not shown) for forming the opening 20 for accommodating the body 7 of the X-ray tube 3 and the oil 22 and a diaphragm 55 for adjusting the oil pressure (see FIG. 6). And a core (not shown) for forming an opening 54 for accommodating therein. In order to form the communication passage 56 for the oil 22 in the mold portion 17, the cores on both sides are connected via a connecting core.

Further, before molding, an electrical connector portion 24 is fixed to the back panel 19 in advance. The electrical connector section 24 is exposed to the outside of the rear panel 19 at the ground potential, and an adapter section 24 </ b> B used as a plug P insertion section, and a back panel 19.
And a base 24A disposed inside the cavity A on the inner side of the base. The base 24A has a screw groove 51 and is inserted into an opening 52 formed in the back panel 19 via a packing 57. Then, the nut 53 is tightened toward the rear panel 19, and the rear panel 19 is sandwiched by the cooperation of the nut 53 and the adapter portion 24B. As a result, the electrical connector section 24 is firmly fixed to the back panel 19.

In this state, when a resin is poured into the cavity A from above, a desired mold portion 17 is formed. At this time, the base portion 24A of the electric connector portion 24 is Embedded in Then, the nut 52 is also embedded in the mold portion 17. Accordingly, the loosening or detachment of the electric connector portion 24 is reliably prevented by the curing of the molding material.

Further, after the resin in the cavity A is cooled and solidified, the side frames 50A, 50B, the bottom frame 50C, and the front frame 50 are formed.
D, but the back panel 19 is
7, the mold portion 17 and the back panel 19 maintain extremely high adhesion. Therefore, the mold part 17 and the back panel 1
9 is significantly improved. Further, a conductive paint is applied to the entire surface of the mold portion 17, and the paint is kept in contact with the back panel 19 at the ground potential, so that electrical conductivity is ensured.
7 contributes to antistatic. Then, the electrical connector section 24
Is embedded in the mold part 17 as a result,
The rear panel 19 does not fall off the mold section 17.

The body 7 of the X-ray tube 3 is housed by such a mold part 17. Considering that the body 7 is charged to a high voltage, the mold part 17 is made of an electrically insulating resin. Used. Also, the electron gun housing 8 on the side of the electron gun 4.
Are at the ground potential and are exposed from the mold portion 17. In this case, since the body 7 is stored in the mold part 17, it is hardly affected by the heat fluctuation of the outside air, and a high temperature but a thermally stable state is maintained. On the other hand, the electron gun 4 is affected by heat radiated from the mold portion 17. As a result, in the X-ray tube 3,
It is necessary to thermally stabilize the part exposed from the mold part 17.

Therefore, as shown in FIGS. 1, 3 and 6, a copper cooling pipe as an example of a first cooling pipe is brought into contact with the surface of the electron gun housing 8 surrounding the electron gun 4. The coolant 30 (for example, water or oil) flows in the cooling pipe 30 by spirally winding the 30.

For example, one end of the cooling pipe 30 is connected to a vinyl pipe 32 via a joint 31, and the other end of the cooling pipe 30 is connected to a vinyl pipe 34 via a joint 33. On the back side of the case 2, a pipe end 35 for refrigerant inflow is fixed on the upper side, and a pipe end 36 for refrigerant outflow is fixed on the lower side. Each of the pipe ends 35, 36 has a T-shape. It is configured to be a bite outside the case 2, but is branched into two branches inside the case 2. Therefore, the upper pipe end 35
Then, the end of one vinyl pipe 32 is fixed, and the other vinyl pipe 34 is fixed to the lower pipe end 36.

As a result, the refrigerant flowing through the upper pipe end 35 by the circulating supply from a refrigerant pump (not shown) or the direct supply from a water pipe flows through the cooling pipe 30 while flowing through the cooling pipe 30 to the electron gun 4 side. The electron gun housing 8 is cooled and discharged to the outside via the pipe end 36. In this way, the coolant flows around the electron gun 4, whereby the temperature on the electron gun 4 side can be quickly stabilized. Then, while controlling the temperature of the refrigerant, the cooling pipe 3
The optimum operating temperature of the X-ray tube 3 is reliably maintained by adjusting the amount and flow rate of the refrigerant within 0 by controlling the pump.

Similarly, a copper cooling pipe 40, which is an example of a second cooling pipe, is crawled so as to come into contact with the outer surface of the front panel 18, and a coolant (for example, water, oil, etc.) ) To flow. As an example of this crawling, cooling pipes 40 are provided on the left and right of the head 9.
The cooling pipe 40 is bent in a U-shape while being attached to the head portion 9 and turned over, and the cooling pipe 40 is attached to the peripheral surface of the flange portion 23 so as to connect the left and right sides.
Contact.

One end of the cooling pipe 40 crawled in this way is connected to a vinyl pipe 42 through a joint 41.
The other end of the cooling pipe 40 is connected to the joint 4
3 is connected to a vinyl pipe 44. Then, one vinyl pipe 4 is attached to the upper pipe end 35.
2 is fixed, and the other vinyl pipe 44 is fixed to the lower pipe end 36.

As a result, the refrigerant flowing through the upper pipe end 35 flows through the cooling pipe 40,
The front panel 18 and the head section 9 are cooled and discharged to the outside via the pipe end 36. As described above, cooling the front panel 18 can promote heat radiation by the front panel 18, and also indirectly cooling the target 5 by cooling the oil 22.

Further, a heat conductive adhesive R may be applied to the electron gun housing 8 so as to surround the spiral cooling pipe 30. This may make it difficult to fix the surface of the cooling pipe 30 in contact with the electron gun accommodating portion 8. The space between the pipes 30 is filled. Therefore, the cooling pipe 30 can be reliably moved around on the electron gun 4 side, and the cooling area can be increased by the adhesive R.

Similarly, a heat conductive adhesive R may be applied to the head portion 9 so as to surround the cooling pipe 40. This is because it is sometimes difficult to fix the surface of the cooling pipe 40 in contact with the front panel 18 made of metal. Therefore, an adhesive R having good thermal conductivity is applied between the front panel 18 and the cooling pipe 40 or the adjacent cooling pipe. The space between 40 is filled. Accordingly, the cooling pipe 40 can be reliably moved around on the front panel 18 side, and the cooling area can be enlarged by the adhesive R. The conductive adhesive R used here includes an adhesive containing metal powder, a silicone-based adhesive, and the like. Further, a conductive paint may be used.

The present invention is not limited to the above-described embodiment. For example, a metal side panel (not shown) is used as a part of a mold at the time of molding a mold portion, and the side panel is electrically connected. The connector section 24 may be fixed. Note that a metal front panel or top panel may be integrally formed with the mold section 17 and the electric connector section 24 may be provided on this. Further, the electrical connector portion may be a drawer cord having a plug portion at the tip and a base portion 24 </ b> A embedded in the mold portion 17.

[0035]

Since the X-ray generator according to the present invention is configured as described above, the following effects can be obtained. That is, an electron emitted from an electron gun in the housing collides with a target, and an X-ray generated by the collision is emitted to the outside through an X-ray emission window. An electrically insulating mold part for surrounding and storing the body of the X-ray tube to be housed, a metal panel fixed to the mold part, fixed to the panel and electrically connected to a target of the X-ray tube The base to be provided with the electrical connector embedded in the mold,
Even if the body of the X-ray tube is housed in the mold section, the optimum operating temperature of the X-ray tube can be reliably maintained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an X-ray generator according to the present invention.

FIG. 2 is a sectional view showing an X-ray tube applied to the X-ray generator of FIG.

FIG. 3 is a sectional view of the X-ray generator.

FIG. 4 is a cross-sectional view showing a mold part.

FIG. 5 is a sectional view taken along line VV of FIG. 4;

FIG. 6 is a sectional view of the X-ray generator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... X-ray generator, 3 ... X-ray tube, 4 ... Electron gun, 5 ... Target, 7 ... Trunk, 8 ... Electron gun accommodating part, 9 ... Head part,
14: X-ray emission window, 17: molded part, 18: front panel (panel), 19: rear panel (panel), 21: electric insulating oil storage part, 23: flange part, 24: electric connector part, 24A: base part , 24B ... Adapter part.

Claims (4)

[Claims] 1. An electron emitted from an electron gun in a housing is caused to collide with a target, and X-rays generated by the collision are emitted from the electron gun.
An X-ray tube having a structure for emitting light to the outside via an X-ray emission window; an electrically insulating mold portion for surrounding and storing a body of the X-ray tube for housing the target therein; and the mold portion. A metal panel fixed to the panel; and an electrical connector section embedded in the mold section, the base section being fixed to the panel and electrically connecting to the target of the X-ray tube. X-ray generator. 2. The panel according to claim 1, wherein the panel forms a part of a mold frame when the mold section is molded.
The X-ray generator according to the above. 3. A metal front panel fixed to the mold section, an electrically insulating oil storage section formed by the mold section, the housing of the X-ray tube, and the front panel, 3. The X-ray generator according to claim 1, further comprising: a flange formed on the housing and in contact with and fixed to an outer surface of the front panel. 4. The X-ray generator according to claim 1, wherein the panel is a rear panel facing a front panel fixed to the mold portion.