JPH02144836A - Rotary anode x-ray tube - Google Patents

Abstract

PURPOSE:To restrain temperature rise of a bearing by lengthening a thermal path between an anode target and the bearing even if when X-rays is produced the anode target is at high temperature. CONSTITUTION:An anode target 3 is firmly attached to the upper portion of a supporting member 4, which has the side of the anode target 3 of a cylindrically-formed rotor 5 integrally bonded at the lower portion thereof, and to the inner periphery on the opposite side of the anode target 3 a cylindrically-formed rotary shaft 6 is bonded at the lower portion and supported by a supporting shaft 8 via ball bearings 7a, 7b so as to be rotationally moved. In such a manner that the rotary shaft 6 and the rotor 5 are bonded together on the opposite side of the anode target 3, a thermal path to be conducted from the anode target 3 through a connecting shaft, the rotor 5 and the rotary shaft 6 to the bearing can be lengthened. It is thus possible to restrain temperature rise of the bearing, corresponding to only lengthened thermal path.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a rotating i-pole Xa tube.

(Prior Art) FIG. 5 is a schematic sectional view showing a conventional rotating anode XIl tube. As shown in this figure, a cathode 101 that emits electrons and an anode target 103 fixed to a rotating shaft 102 are arranged facing each other in a vacuum container 100 that is airtight to a high vacuum. are ball bearings 104a, 104
A fixing part 1 fixed to the lower part of the vacuum container 100 via b
It is rotatably supported by 05. A rotor 106 is fixed to the rotating shaft 102, and a vacuum container 1 located outside the rotor 106 is attached to the rotor 106.
A stator (not shown) is disposed on the outer periphery of the rotor 106, and the rotor 106 and the stator constitute a drive motor.

The conventional rotating anode Xli tube is constructed as described above, and the rotor 106 is rotated by electrode guidance of a stator (not shown), and the rotating shaft 102. vA pole target 103 rotates as one! Ru. And the rotating anode Targera! -103 is collided with electrons emitted from the negative l4i101 hl + to generate X-rays.

At this time, Yotachi Tagutsu! -1034! The heat generated along with the X-rays raises the temperature to over 1000°C, and most of this heat is radiated outside the vacuum container 100 by radiation.
A part of it is conducted to the rotating shaft 102, so the ball bearing 104a
, 104b, the heat is also transferred to the fixed part 105. Therefore, ball bearings 104a, 104b (7) tWli are 300~
Since the temperature is about 500℃, the ball bearings 104a, 1
04b (especially l1i111i targtsu l-103
of the side ball bearing 104a)! ? 1. Sliding ability is reduced and rotational failures are more likely to occur, which is a factor in shortening the lifespan of rotating rotary X-ray tubes.

(Problems to be Solved by the Invention) As described above, in the conventional rotating anode X-ray tube, the C ball bearings 104a, 104b (especially , the double bearing 104a) becomes high temperature 1. Therefore, the solid lubricant such as the two Km bearing 104a, 104b (7) Therefore, there is a problem in that the ball bearings 104a and 104b are more likely to malfunction, and the life of the rotating anode X-ray tube is shortened.

The present invention aims to solve the above-mentioned problems by: 1. , is, X
An object of the present invention is to provide a rotating anode X-ray tube that can suppress the upper limit of the temperature of the bearing during radiation generation.

[Structure of the Invention] (First stage for solving the problem) In order to solve the above-mentioned problem, the present invention provides a cathode that emits electrons in a t4 empty container, and a cathode that emits electrons by collision with the cathode. an anode targeter 1- that generates X-rays; a support member to which the anode target is physically fixed to one end;
A stator, one end of which is integrally fixed to the other end of the support member, is disposed facing the outside of the vacuum container.
A rotor constituting the rotor, a cylindrical rotating shaft whose one end is connected to the anode target on the opposite side of the rotor, and a cylindrical rotating shaft whose one end is fixed to the empty container and which is connected to the anode target through a plurality of bearings. The spindle was configured to include a support shaft that supports the rotating shaft so as to be freely spinning.

Further, the rotor may be formed by laminating a plurality of members, and furthermore, a hole may be formed in the support member to penetrate in the axial direction.

(Function) According to the present invention, the rotating shaft and the rotor are connected to the anode target roller 1-
By joining on the opposite side of the anode, it is possible to improve the heat path by conduction from the anode to the bearing through the connecting shaft, rotor, and rotating shaft, so the temperature of the bearing increases by the length of the heat path. can suppress the world.

(Embodiment) The present invention will be described in detail below based on the illustrated embodiment (21 Situation 46°). Figure 1 is a sectional view showing a rotating anode X-ray tube according to the first embodiment of the present invention. J shown in this figure, sea urchin, vacuum container 1
Inside, a cathode 2 that emits electrons and a vA pole target 3 that generates X-rays due to collision of electrons emitted from the cathode 2 are placed facing each other. , cathode 2 is vacuum container 1
The support member 4 is attached to the -F portion of the support member 4, and the support member 4 is fixed to the upper part of the support member 4. Further, at the lower part of the support member 4, an anode target plate 1-311114 of the rotor 5 formed in a cylindrical shape is joined to the body, and on the outer periphery of the vacuum plate I located outside the rotor 5, the rotor 5 A stator (not shown) is provided to drive Tanabata horizontally.

F section of rotation T-5, Ill '5, FIA pole target l
A cylinder formed in a cylindrical shape is connected to the inner circumferential surface on the opposite side of I/J, and the rotation width 6 is supported via ball bearings 7a and 7b. It is rotatably supported. The lower part of the support shaft 8 is fixed to the vacuum container 1.

Although not shown in FIG. 1, there is oil as a cold W medium between the outside of the vacuum container 1 and the X-ray tube storage container.

The rotary opening X-ray tube according to the present invention is constructed as described above 113.The rotating shaft 6 is connected to the electric current of the stator (not shown) by going up to one induction and rotating the rotor 5. , the support member 4, and the anode target 3 are rotated together. Then, electrons emitted from the cathode 2 collide with an anode target 3 rotating at high speed to generate X-rays.

XIi! At the time of occurrence, l! The l-pole target 3 reaches a high temperature of 1000° C. or more due to the heat generated together with XIQ.

Most of the heat generated in the anode target 3 is rA
Although heat is radiated to the outside of the vacuum vessel 1 by radiation, a portion of the heat is conducted to the support member 4, so that the heat is also transferred to the ball bearings 7a, 7b and the support shaft 8 through the rotor 5 and rotating shaft 6.

At this time, since the rotor 5 and the rotating shaft 6 are joined on the opposite side to the anode target 3, the heat path becomes long, and the ball bearing 7
The heat conducted to ball bearings 7a and 7b is significantly reduced, and
, 7b can be suppressed.

FIG. 2 is a sectional view showing a rotating anode X-ray tube according to a second embodiment of the present invention. In this example, the rotor 5 is
and an inner cylinder 5b, the outer cylinder 5a is made of a material with good thermal conductivity, such as copper, and the inner cylinder 5b is made of a material that is stronger than copper and has poor thermal conductivity, such as iron. This is the structure formed. Other structures are the same as those of the embodiment described above.

In this way, in this example, the rotor 5 has a two-layer structure, which is advantageous in terms of strength.Moreover, since the outer cylinder 5a and the inner cylinder 5b have different thermal conductivities, the ball bearing 7a can be inserted through the rotating shaft 6. , 7b side can be further reduced, and temperature rise can be suppressed.

FIG. 3 is a sectional view showing a rotating anode X-ray tube according to a third embodiment of the present invention. In this example, the support member 4 has a structure in which n holes 9 are formed through it in the axial direction.

As described above, in this example, by forming the hole 9 in the support member 4, the presser plate 11 can be fixed with the screw 10 to a part of the support shaft 8 to which the ball bearings 7a and 7b are attached through the hole 9. Since it is possible, ball bearings 7a, 7b,
After the rotating shaft 6, rotor 5, support shaft member 4, and anode target 3 are assembled, the ball bearing 7a can be easily and reliably fixed to the support shaft 8. Other configurations are similar to the embodiment shown in FIG. In addition, the hole 9 in which the presser plate 11 is fixed to the upper part of the support shaft 8 with the screw 1o may be closed with a heat shield plate.

FIG. 4 is a sectional view showing a rotating anode X-ray tube according to a fourth embodiment of the present invention. In this example, a flow path 8a is formed in the axial direction of the support shaft 8 for guiding cooling oil injected to the outside of the vacuum container 1. The other configurations are similar to the embodiment shown in FIG.

In this way, in this example, oil is allowed to flow into the flow path 8a formed in the support shaft 8, and the ball bearings 7a, 7 become hot due to this oil.
Since the ball bearings 7a and 7b can be efficiently cooled,
The temperature rise of 7b can be further suppressed.

[Effects of the Invention] As specifically explained above based on the embodiments, according to the present invention, the thermal path between the anode target and the bearing is lengthened even when the anode target becomes high temperature when X-rays are generated. This makes it possible to suppress the temperature rise of the bearing. Therefore,
Since deterioration of the aipt function of the bearing is suppressed, malfunction of the bearing and the like can be prevented and a rotating anode X-ray tube with a long life can be provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a rotating anode X-ray tube according to the present invention, and FIGS. 2, 3, and 4 are cross-sectional views showing rotating anode X-ray tubes according to other embodiments of the present invention, respectively. FIG. 5 is a sectional view showing a conventional rotating anode X-ray tube. 1... Vacuum container 2... Cathode 3...
Anode target 4... Support member 5... Rotor 5a... Outer cylinder 5b... Inner cylinder
6...Rotating shafts 7a, 7b...Ball bearings
8... Support shaft 9... Hole

Claims (3)

[Claims] (1) A cathode that emits electrons, an anode target that generates X-rays by collision of the electrons emitted from the cathode, and a support member having the anode target integrally fixed to one end thereof, in a vacuum container; a rotor that constitutes a drive motor with a stator whose one end side is integrally fixed to the other end side of the support member and which is disposed facing the outside of the vacuum container; and the anode target of the rotor. It is characterized by comprising a cylindrical rotating shaft whose one end side is joined on the opposite side, and a support shaft whose one end side is fixed to the vacuum container and rotatably supports the rotating shaft via a plurality of bearings. Rotating anode X-ray tube. (2) The rotating anode X-ray tube according to claim (1), wherein the rotor is formed by laminating a plurality of members. (3) The rotary anode X-ray tube according to claim 1 or 2, wherein a hole is formed in the support member to pass through the support member in the axial direction.