JPH0864386A - Rotary anode x-ray tube device - Google Patents

Abstract

PURPOSE: To improve the cooling efficiency by interposing an insulating member outside of a bulb at a position opposite to the back of a rotary anode. CONSTITUTION: The insulating oil 18 is filled between an X-ray tube container 10 and a glass bulb 11. An insulating member 17 as a radiation heat absorber is provided outside of the bulb 11 near at a position opposite to the back surface 13a of a rotary anode 13. When the X-ray is generated, heating at the anode 13 is especially large. This heating is radiated, or transmitted to the surface 13a, and diverged as the radiation heat. This radiation heat is effectively absorbed by the insulating member 17 provided so as to be opposite to the surface 13a. In the case where a cooling ring 19 is provided in the back side of the insulating member 17, the X-ray tube is effectively cooled. Inside of the hollow ring 19 is filled with the coolant (for example, insulating oil), and the coolant is circulated between the ring 19 and a heat exchanger. In the case where the insulating member 17 is extended to a part opposite to a rotor 15, heating of the rotor part can be effectively absorbed, and the cooling efficiency is more improved. Radiation heat from the anode 13 is thereby effectively absorbed so as to improve the cooling efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary anode X-ray tube apparatus used in the medical field, and more particularly to cooling of a rotary anode X-ray tube apparatus.

[0002]

2. Description of the Related Art A rotating anode X-tube generates a large amount of heat when generating X-rays, and therefore must be cooled. Therefore, conventionally, the heat of the rotating anode (target) is radiated to be radiated to each member of the tube container of the X-ray tube and the insulating oil filled in the tube container.

Further, in order to improve the efficiency of heat dissipation from the rotating anode, a ceramic coating having a high emissivity or a high emissivity is applied to the rear surface of the rotating anode, that is, the rear surface of the surface facing the cathode (target surface). Of graphite has been provided.

[0004]

[Problems to be Solved by the Invention] With the advancement of diagnostic technology in recent years, the rotating anode X-ray tube device has been used more and more frequently, and it is necessary to improve the cooling capacity of the X-ray tube container. Is increasing. However, there is a limit to the heat dissipation from the rotating anode, and if the operating temperature of the rotating anode is raised to improve the heat dissipation, the gas discharge from the rotating anode increases, and discharge occurs in the tube, or the bearing of the rotating mechanism of the rotating anode. There was a case where the temperature of the part increased and abnormal rotation noise occurred. It is an object of the present invention to solve such a problem and to provide a rotating anode X-ray tube device which is more excellent in cooling efficiency than the conventional cooling method.

[0005]

The rotary X-ray tube apparatus of the present invention made to solve the above-mentioned problems is an X-ray tube in which a rotary anode and a cathode are arranged to face each other in a glass bulb. In the rotating anode X-ray tube device housed in the tube container, an insulating member for absorbing radiant heat is interposed outside the glass bulb and at a position facing the back surface of the rotating anode. The following is a description of how this device works.

[0006]

In the rotary anode X-ray tube device of the present invention, the heat generated by the rotary anode and dissipated by radiation is absorbed by the insulating member which is provided in the vicinity of the outside of the glass bulb and which absorbs the radiant heat. Due to the presence of this insulating member, the heat from the rotating anode can be efficiently absorbed, and the cooling efficiency can be improved without raising the operating temperature of the target. In particular, since the rotating anode has the highest temperature, the heat absorption efficiency is improved by providing an insulating member that promotes heat absorption at a position facing the back surface of the rotating anode.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional view of an embodiment of a rotary anode X-ray tube device according to the present invention. This X-ray tube device includes an X-ray tube 12 whose inside is sealed by a glass bulb 11 in an X-ray tube container 10.
Is included. In the X-ray tube 12, a rotary anode 13 and a cathode 14 are arranged so as to face each other, and the rotary anode 13 is rotatably supported by a motor mechanism including a rotor 15 and a stator 16. The surface of the rotating anode 13 facing the cathode side is the target surface, and the back surface 13a thereof is coated with a ceramic coating having a high emissivity in order to improve the radiation efficiency. Similarly, the outer surface 15a of the rotor 15 is also coated with a ceramic coating for improving the radiation efficiency. This is to efficiently dissipate the heat generated in the rotor. Ceramic coating is Al2 O3, TiO2, ZnO
It is generally applied by spraying at least one of the two on the surface to be coated, but other than this may be applied. For example, instead of coating the back surface 13a of the rotating anode, a graphite member may be joined by brazing.

An insulating member 17, which is a radiant heat absorber, is provided outside the glass bulb 11 in the vicinity of a position facing the back surface 13a of the rotary anode 13. Although ceramics or resin is used as the material of the insulating member 17, for example, AlN is preferable from the viewpoint of electrical insulation, heat resistance, and thermal conductivity. The insulating member 17 may be provided with the same ceramic coating as the back surface of the target so that the radiant heat can be absorbed more efficiently.

In this embodiment, the insulating member 17 is extended to a portion facing the rotor 15 so that the radiant heat on the outer surface of the rotor can be absorbed. In this case, it is necessary to insulate between the rotor 15 having a high voltage and the stator 16 having a ground potential, but since the insulating member 17 originally has an insulating property, no particular problem occurs.

The space between the X-ray tube container 10 and the glass bulb 11 is filled with insulating oil 18 and is cooled by this insulating oil. The insulating member 1
In order to effectively release the heat absorbed by 7, the insulating member 17
It is more preferable to provide a cooling ring 19 on the back side of the. The cooling ring 19 has a hollow shape, and the inside thereof is filled with a refrigerant (for example, insulating oil) so that the refrigerant circulates between it and a heat exchanger (not shown). The cooling ring 19 may be at ground potential and is made of copper, aluminum or alloys thereof.

Heat is generated by generating X-rays by the rotating X-ray tube device having the above-mentioned configuration. In particular, the heat generation at the rotating anode 13 as a target facing the cathode is large. The heat generated here is radiated or transferred to the back surface 13a of the anode and radiated from here as radiant heat. The emitted radiant heat is effectively absorbed by the insulating member 17 provided outside the glass bulb 11 so as to face the back surface 13a. Furthermore, the insulating member 1
If is cooled by the cooling ring 19, this effectively cools the X-ray tube. If the insulating member 17 is extended to the portion facing the rotor 15, the heat generated in the rotor portion can be effectively absorbed, and the cooling efficiency is further improved.

[0012]

As described above, according to the present invention,
By arranging an insulating member that absorbs radiant heat near the outside of the glass bulb that faces the radiating surface of the rotating anode, it is possible to effectively absorb the radiant heat from the rotating anode, which generates a large amount of heat, and improve cooling efficiency. You can

[Brief description of drawings]

FIG. 1 is a sectional view showing a rotary X-ray tube device according to an embodiment of the present invention.

[Explanation of symbols]

 10: X-ray tube container 11: Glass bulb 12: X-ray tube 13: Rotating anode (target) 13a: Rotating anode back surface 14: Cathode 15: Rotor 15a: Rotor outer surface 16: Stator 17: Insulating member 18: Insulating oil

Claims (1)

[Claims] 1. A rotary anode X-ray tube apparatus in which an X-ray tube having a rotary anode and a cathode arranged in a glass bulb so as to face each other is housed in an X-ray tube container. A rotary anode X-ray tube device, wherein an insulating member for absorbing radiant heat is interposed at a position facing the back surface of the.