JP4334682B2 - X-ray generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
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]
[Prior art]
Conventionally, as techniques in such a field, there are JP-A-6-162974, JP-A-6-84490, JP-A-6-36720, and JP-A-5-290768. In the X-ray generators described in these publications, means for releasing high heat generated from the X-ray tube to the outside and maintaining stable operating characteristics is disclosed. Specifically, a cooling passage is formed in the target support body, and cooling water is passed through the passage to cool the target serving as a heat generation source.
[0003]
[Problems to be solved by the invention]
However, the conventional X-ray generator described above has the following problems. That is, since the structure for cooling the target support is adopted, it is difficult to apply to the mold type X-ray tube, and when the mold is formed so as to wrap the target support, the cooling pipe and the target support are used. There is a problem that it is difficult to maintain contact with the liquid crystal and it is difficult to obtain a desired cooling efficiency.
[0004]
The present invention has been made to solve the above-described problems. In particular, even when the body of the X-ray tube is housed in the mold portion, it is necessary to reliably maintain the optimum operating temperature of the X-ray tube. It is an object of the present invention to provide an X-ray generator configured to be fastened.
[0005]
[Means for Solving the Problems]
The X-ray generator of the present invention according to claim 1 causes electrons emitted from an electron gun in a casing to collide with a target, and emits X-rays generated by the collision to the outside through an X-ray emission window. An X-ray tube having a structure;
An electrically insulating mold part that surrounds and stores a body part of an X-ray tube that accommodates the target;
A metal panel fixed to the mold part;
An electrical connector portion fixed to the panel and having a base portion electrically connected to the target of the X-ray tube embedded in the mold portion ;
The panel is characterized in that it forms a part of the mold when molding the mold part .
[0006]
In this X-ray generator, the target of the X-ray tube is accommodated in a body portion, and since this body portion is charged to a high voltage, it is stored in an electrically insulating mold portion in consideration of electrical sealing properties. Is difficult to cool. Therefore, the target is indirectly cooled by cooling the mold part instead of directly cooling the target. In this case, a metal panel aimed at improving the cooling efficiency is fixed to the mold part. Furthermore, by fixing the electrical connector part to such a panel and embedding the base part of the electrical connector part in the mold part, the adhesion between the mold part and the electrical connector part is improved, and the electrical connector part is loosened or disconnected from the panel. Is prevented appropriately, and the panel is prevented from falling off from the mold part. Such an electrical connector part makes it possible to separate the high voltage conversion unit from the X-ray generator, and at the same time, light weight and compactness are achieved.
[0007]
Furthermore, the panel, to name some of the mold during molding of the molded part. In this case, although the metal panel aiming at the improvement in cooling efficiency is fixed to the mold part, it is not simply fixed, but the metal panel is used to further improve the thermal conductivity between the mold part and the panel. It is used as a part of the mold at the time of molding the mold part to improve the adhesion between the mold part and the panel.
[0008]
According to a third aspect of the present invention, an X-ray generator of the present invention collides electrons emitted from an electron gun in a housing with a target, and emits X-rays generated by the collision to the outside through an X-ray emission window. An X-ray tube having a structure;
An electrically insulating mold part that surrounds and stores a body part of an X-ray tube that accommodates the target;
A metal back panel fixed to the mold part;
An electrical connector part fixed to the back panel and having a base part electrically connected to the target of the X-ray tube embedded in the mold part;
A metal front panel fixed to the mold part;
An electrically insulating oil container formed by a mold part, an X-ray tube housing and a front panel;
And a flange portion that is formed on a housing of the X-ray tube and is fixed in contact with the outer surface of the front panel.
In this X-ray generator, the target of the X-ray tube is accommodated in a body portion, and since this body portion is charged to a high voltage, it is stored in an electrically insulating mold portion in consideration of electrical sealing properties. Is difficult to cool. Therefore, the target is indirectly cooled by cooling the mold part instead of directly cooling the target. In this case, a metal panel aimed at improving the cooling efficiency is fixed to the mold part. Furthermore, by fixing the electrical connector part to such a panel and embedding the base part of the electrical connector part in the mold part, the adhesion between the mold part and the electrical connector part is improved, and the electrical connector part is loosened or disconnected from the panel. Is prevented appropriately, and the panel is prevented from falling off from the mold part. Such an electrical connector part makes it possible to separate the high voltage conversion unit from the X-ray generator, and at the same time, light weight and compactness are achieved .
Furthermore , a metal front panel fixed to the mold part, an electrically insulating oil housing part formed by the mold part, the X-ray tube housing and the front panel, and an X-ray tube housing and the outside of the front panel are formed. Ru and a flange portion to be fixed in contact with the surface. 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 placed on the end face of the mold part contacts the oil. Therefore, it is possible to promote heat dissipation by the front panel.
[0009]
Moreover , it is preferable that a panel is a back panel which faces the front panel fixed to the mold part. If comprised in this way, since an X-ray tube can be fixed using a front panel and an electrical connector part can be fixed using a back panel, heat dissipation is carried out by cooperation with a front panel and a back panel. The effect can be further enhanced, and the X-ray tube and the electrical connector portion can be aligned in a row, making it easy to apply a high voltage to the target from behind the X-ray tube.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of an X-ray generator according to the present invention will be described below in detail with reference to the drawings.
[0011]
FIG. 1 is a perspective view showing an X-ray generator according to the present invention. The X-ray generator 1 shown in the figure is of a type in which an X-ray tube 3 is housed in a metal case 2 and does not incorporate a high-voltage generator, thereby achieving compactness and weight reduction. . In other words, the X-ray generator 1 is separated from the 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 built, thereby simultaneously reducing the weight and size. Maintenance is also facilitated, 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 convenience is greatly improved.
[0012]
As shown in FIG. 2, the X-ray tube 3 accommodated in the case 2 is configured as a microfocus X-ray tube used for nondestructive inspection or the like. There is an end window type, but this is an end window type. The X-ray tube 3 accommodates 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.
[0013]
The housing S is divided into a plurality of parts and extends in the horizontal direction to receive a glass barrel 7 for receiving the target 5, a metal electron gun receiving portion 8 for receiving the electron gun 4, the barrel 7, and the electron It consists of a metal head portion 9 that connects the gun housing portion 8. That is, the electron gun housing part 8 forms a part of the housing S on the electron gun 4 side, and the head part 9 and the body part 7 form a part of the housing S on the target 5 side. Are connected and fixed to each other to form one housing S.
[0014]
Further, a ceramic stem 11 is fitted on the top of the electron gun housing portion 8, and an X-ray emission window 14 is formed on the end surface of the head portion 9 so as to face the target 5. The electron gun 4 includes a heater electrode 15a, a cathode 15b, a grid electrode 15c, and a focus electrode 15d, and is fixed in the electron gun accommodating portion 8 via a support column 15e. The tip of the target 5 is cut obliquely at about 25 °, and the target member 5b is brazed.
[0015]
Therefore, when the cathode electrode 15b is heated by the heater electrode 15a, electrons are emitted from the cathode electrode 15b at a constant temperature. 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 are emitted to the outside through the X-ray exit window 14.
[0016]
As shown in FIG. 3, the body portion 7 of such an X-ray tube 3 is accommodated in a rectangular parallelepiped mold portion 17 formed of an electrically insulating resin mold material. A front panel 18 and a back panel 19 made of nickel, chromium, copper, etc. plated on brass are fixed. The front panel 18 is integrated with the mold part 17 by an adhesive or the like, and the back panel 19 is used as a mold at the time of molding and is integrally formed with the mold part 17. The mold part 17 is provided with an opening 20 for inserting the body part 7 of the X-ray tube 3 from the front panel 18 side.
[0017]
Further, when the body portion 7 of the X-ray tube 3 is inserted into the opening 20 and the X-ray tube 3 is fixed to the front panel 18, the inner wall surface of the mold portion 17, the inner wall surface of the front panel 18, and the outer surface of the body portion 7. A desired electrically insulating oil accommodating portion 21 is formed with the wall surface. The housing portion 21 is filled with electrically insulating oil 22, and the oil 22 prevents the high voltage of the target 5 from being transmitted to the outside through the mold portion 17.
[0018]
The oil 22 filled between the mold part 17 and the X-ray tube 3 becomes high temperature due to the influence of the target 5. However, since the metal front panel 18 disposed on the end surface of the mold part 17 is brought into contact with the oil 22, the heat dissipation effect of the oil 22 by the metal front panel 18 is enhanced. Further, in order to improve the heat dissipation effect of the mold part 17, the upper plate 26 is disposed so as to contact the upper surface of the mold part 17. Needless to say, the back panel 19 also has a similar heat dissipation effect.
[0019]
The X-ray tube 3 is fixed via screws 25 so that the flange portion 23 provided on the head portion 9 is brought into contact with the front panel 18 (see FIG. 2), and the oil 22 After being fixed to the front panel 18, it is filled from a predetermined location. Further, an electrical connector portion 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, and the electrical connector portion 24 is connected via a connecting portion 28. The target 5 is connected to the rear end 5a.
[0020]
Here, the front panel 18 and the back panel 19 are adopted as the one that cools the mold part 17 and indirectly cools the target 5, but the back panel 19 is not simply fixed to the mold part 17, but a mold. In order to further improve the thermal conductivity and electrical conductivity between the portion 17 and the panel 19, the metal panel 19 is used as a part of a mold for molding the mold portion 17. Adhesion with the panel 19 is improved.
[0021]
Specifically, as shown in FIGS. 4 and 5, when the rectangular parallelepiped mold portion 17 is molded with resin, the side frames 50A, 50B, the bottom frame 50C, the front frame 50D, and the back panel 19 are A rectangular parallelepiped cavity A having an opening is defined. Further, in the cavity A, a core (not shown) for forming the body 7 of the X-ray tube 3 and the opening 20 for accommodating 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 the same. And in order to shape | mold the communication path 56 of the oil 22 in the mold part 17, the cores of both sides are connected via the connection core.
[0022]
Further, the electrical connector portion 24 is fixed to the back panel 19 in advance before molding. The electrical connector portion 24 is exposed to the outside of the back panel 19 that is at the ground potential, and is used as an insertion portion for the plug P, and inside the cavity A on the inner side of the back panel 19. And a base portion 24A. The base portion 24 </ b> A has a thread 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 back panel 19, and the back panel 19 is sandwiched by the cooperation of the nut 53 and the adapter portion 24B. As a result, the electrical connector portion 24 is firmly fixed to the back panel 19.
[0023]
In this state, when 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 electrical connector portion 24 is embedded in the mold portion 17. . The nut 52 is also embedded in the mold part 17. Therefore, the hardening of the molding material reliably prevents the electrical connector portion 24 from being loosened or pulled out.
[0024]
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 50D are removed, but the back panel 19 is left attached to the mold part 17. Therefore, extremely high adhesion is maintained between the mold part 17 and the back panel 19. Therefore, the thermal conductivity between the mold part 17 and the back panel 19 is remarkably improved. In addition, a conductive paint is applied to the entire surface of the mold portion 17, and this paint is kept in contact with the back panel 19 having a ground potential, thereby ensuring electrical conductivity and preventing the mold portion 17 from being charged. Contribute. As a result of the base portion 24 </ b> A of the electrical connector portion 24 being embedded in the mold portion 17, the back panel 19 does not fall off from the mold portion 17.
[0025]
Although the barrel portion 7 of the X-ray tube 3 is stored by such a mold portion 17, in consideration of the fact that the barrel portion 7 is charged to a high voltage, an electrically insulating resin is used for the mold portion 17. . Further, the electron gun housing portion 8 on the electron gun 4 side is at a ground potential and is exposed from the mold portion 17. In this case, since the body part 7 is stored in the mold part 17, it is hardly affected by the heat fluctuation of the outside air and is kept in a thermally stable state even at a high temperature. On the other hand, the electron gun 4 side is affected by heat emitted from the mold part 17. As a result, in the X-ray tube 3, it is necessary to thermally stabilize the part exposed from the mold part 17.
[0026]
Therefore, as shown in FIGS. 1, 3, and 6, a copper cooling pipe 30, which is an example of a first cooling pipe, is spiraled so as to come into contact with the surface of the electron gun housing portion 8 that surrounds the electron gun 4. The refrigerant (for example, water or oil) is caused to flow in the cooling pipe 30.
[0027]
For example, one end of the cooling pipe 30 is connected to the vinyl pipe 32 via the joint portion 31, and the other end of the cooling pipe 30 is connected to the vinyl pipe 34 via the joint portion 33. Further, a pipe end 35 for inflow of refrigerant is fixed on the upper side on the back side of the case 2, and a pipe end 36 for outflow of refrigerant is fixed on the lower side, and each of the pipe ends 35, 36 has a T shape. It is configured and is a mouthful outside the case 2, but is bifurcated inside the case 2. Therefore, the end of one vinyl pipe 32 is fixed to the upper pipe end 35, and the other vinyl pipe 34 is fixed to the lower pipe end 36.
[0028]
As a result, the refrigerant that has flowed in through the upper pipe end 35 by circulation supply from a refrigerant pump (not shown) or direct supply from a water pipe flows through the cooling pipe 30 and accommodates the electron gun on the electron gun 4 side. The part 8 is cooled and discharged to the outside through the pipe end 36. Thus, the temperature of the electron gun 4 can be quickly stabilized by allowing the refrigerant to flow around the electron gun 4. And while controlling the temperature of a refrigerant | coolant, the optimal operating temperature of the X-ray tube 3 is reliably maintained by adjusting the refrigerant | coolant amount and the flow velocity in the cooling pipe 30 with pump control.
[0029]
Similarly, a copper cooling pipe 40 that is an example of the second cooling pipe is wound around so as to contact the outer surface of the front panel 18, and a refrigerant (for example, water or oil) flows in the cooling pipe 40. Let As an example of this scooping, the cooling pipe 40 is bent in a U shape while being attached to the head portion 9 on the left and right sides of the head portion 9 and inverted, and the cooling pipe 40 has a flange portion so as to connect the left and right sides. The front panel 18 is brought into contact with the peripheral surface 23.
[0030]
One end of the cooling pipe 40 thus wound is connected to the vinyl pipe 42 via the joint portion 41, and the other end of the cooling pipe 40 is connected to the vinyl pipe 44 via the joint portion 43. Then, the end of one vinyl pipe 42 is fixed to the upper pipe end 35, and the other vinyl pipe 44 is fixed to the lower pipe end 36.
[0031]
As a result, the refrigerant flowing in through the upper pipe end 35 cools the front panel 18 and the head portion 9 while flowing in the cooling pipe 40, and is discharged to the outside through the pipe end 36. Thus, cooling the front panel 18 can promote heat dissipation by the front panel 18, and by cooling the oil 22, the target 5 can be indirectly cooled.
[0032]
Further, the heat transfer adhesive R may be applied to the electron gun housing portion 8 so as to wrap the spiral cooling pipe 30. This is because it may be difficult to contact and fix the surface of the cooling pipe 30 to the electron gun housing portion 8, so that the adhesive R having good thermal conductivity is cooled between the electron gun housing portion 8 and the cooling pipe 30 or adjacent thereto. The space between the pipes 30 is filled. Therefore, the cooling pipe 30 is reliably driven on the electron gun 4 side, and the adhesive area R increases the cooling area.
[0033]
Similarly, a heat conductive adhesive R may be applied to the head portion 9 so as to wrap the cooling pipe 40. This is because it may be difficult to contact and fix the surface of the cooling pipe 40 to the metal front panel 18, so that the adhesive R having good thermal conductivity is applied between the front panel 18 and the cooling pipe 40 or adjacent to the cooling pipe 40. Between 40 is filled. Therefore, the cooling pipe 40 is reliably wound around the front panel 18 side, and the cooling area is increased by the adhesive R. Here, examples of the conductive adhesive R to be used include an adhesive containing metal powder and a silicone-based adhesive. Also, a conductive paint may be used.
[0034]
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 forming the mold part, and the electric connector part 24 is used for the side panel. May be fixed. Alternatively, a metal front panel or top panel may be integrally formed with the mold part 17 and the electrical connector part 24 may be provided thereon. Further, the electrical connector portion may be a drawer cord having a plug portion at the tip and the base portion 24A embedded in the mold portion 17.
[0035]
【The invention's effect】
Since the X-ray generator according to the present invention is configured as described above, the following effects are obtained. That is, the X-ray generator of the present invention according to claim 1 causes electrons emitted from the electron gun in the enclosure to collide with the target, and the X-rays generated by the collision are externally transmitted through the X-ray emission window. An X-ray tube having a structure for emitting light, an electrically insulating mold portion surrounding and storing a body portion of the X-ray tube containing the target, a metal panel fixed to the mold portion, and a panel And a base part that is fixed and electrically connected to the target of the X-ray tube and an electrical connector part embedded in the mold part, and the panel forms a part of the mold when molding the mold part. Even if the tube body is housed in the mold, the optimum operating temperature of the X-ray tube can be reliably maintained.
According to a third aspect of the present invention, there is provided an X-ray generator according to the present invention, in which electrons emitted from an electron gun in a housing collide with a target, and X-rays generated by the collision are externally transmitted through an X-ray emission window. An X-ray tube having a structure that emits light, an electrically insulating mold portion that surrounds and stores a body portion of the X-ray tube that houses the target, a metal back panel fixed to the mold portion, and a back surface An electrical connector portion in which a base portion fixed to the panel and electrically connected to a target of the X-ray tube is embedded in the mold portion, a metal front panel fixed to the mold portion, a mold portion and an X-ray tube The body portion of the X-ray tube is provided with an electrically insulating oil housing portion formed by the housing and the front panel, and a flange portion that is formed on the housing of the X-ray tube and fixed to the outer surface of the front panel. mold Even those housed within, it is possible to reliably maintain the optimum operating temperature of the X-ray tube.
[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 cross-sectional view showing an X-ray tube applied to the X-ray generator of FIG.
FIG. 3 is a cross-sectional view of the X-ray generator.
FIG. 4 is a cross-sectional view showing a mold part.
5 is a cross-sectional view taken along line VV in FIG.
FIG. 6 is a cross-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 ... Body part, 8 ... Electron gun accommodating part, 9 ... Head part, 14 ... X-ray emission window, 17 ... Mold part , 18 ... front panel (panel), 19 ... back panel (panel), 21 ... electrical insulating oil accommodating part, 23 ... flange part, 24 ... electric connector part, 24A ... base part, 24B ... adapter part.

Claims (4)

An X-ray tube having a structure in which electrons emitted from an electron gun in a housing collide with a target and X-rays generated by the collision are emitted to the outside through an X-ray emission window;
An electrically insulating mold part that surrounds and stores a body part of the X-ray tube containing the target therein;
A metal panel fixed to the mold part;
A base part fixed to the panel and electrically connected to the target of the X-ray tube, and an electrical connector part embedded in the mold part ;
The X-ray generator according to claim 1, wherein the panel forms a part of a mold when the mold part is molded . Wherein the panels, X-rays generating apparatus according to claim 1, characterized in that a rear panel facing the front panel is secured to the mold portion. An X-ray tube having a structure in which electrons emitted from an electron gun in a housing collide with a target and X-rays generated by the collision are emitted to the outside through an X-ray emission window;
An electrically insulating mold part that surrounds and stores a body part of the X-ray tube containing the target therein;
A metal back panel fixed to the mold part;
An electric connector part fixed to the back panel and electrically connected to the target of the X-ray tube and embedded in the mold part;
A metal front panel fixed to the mold part;
An electrically insulating oil containing part formed by the mold part, the housing of the X-ray tube and the front panel;
An X-ray generation apparatus comprising: a flange portion that is formed on the housing of the X-ray tube and is fixed in contact with an outer surface of the front panel. The X-ray generator according to claim 3, wherein the back panel forms a part of a mold when the mold part is molded.

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