JP2531698B2 - Rotating anticathode X-ray device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention circulates a cooling liquid inside a hollow rotating anticathode rotatably supported in a vacuum container and irradiates the surface with an electron beam. The present invention relates to a rotating anticathode X-ray device for generating X-rays, and in particular, enables the rotational speed of the rotating anticathode to be reasonably increased, while at the same time controlling the flow of the cooling liquid flowing inside the rotating anticathode. It relates to the one which improved and improved the allowable load.

[Prior Art] As a rotary anticathode X-ray device of this type, conventionally, for example,
The one described in Japanese Examined Patent Publication No. 52-46679 is known.

In the case of the one described in the above publication, in short, two fixed partition walls are provided inside the rotating anticathode, and cooling water discharged from the outer peripheral portion of the rotating anticathode toward the central portion is made to flow between the fixed partition walls. , The discharged cooling water is prevented from rotating together with the rotating anticathode so that centrifugal force does not act on the discharged cooling water, thereby improving the circulation of the cooling water, This is intended to improve the cooling efficiency.

[Problems to be Solved by the Invention] By the way, in the conventional example, by providing a fixed partition wall inside the rotating anticathode, the rotation of the cooling water rotating together with the rotating anticathode is stopped so that centrifugal force does not act. It was done.

Therefore, the rotating wall (inner wall of the rotating anticathode) and the stationary wall (fixed partition) face each other with the cooling water sandwiched inside the rotating anticathode.

Moreover, since the distance between the rotating wall and the stationary wall is usually set to the minimum necessary to secure the flow rate,
Shear stress due to the viscosity of water acts between these two walls, and an extremely large torque is required to increase the permissible load by increasing the rotation speed of the rotating anticathode.

Such a large torque can be obtained by using a powerful motor, but if the powerful motor forcibly increases the rotation speed, an unreasonable force is applied to the inside of the rotating anticathode, causing vibration or in extreme cases. May damage the rotating anticathode.

In addition, a structure in which a fixed body (fixed partition wall) fixed to one point outside is provided inside a rotating body (rotating anticathode) that rotates at high speed has various difficult problems from the viewpoint of a mechanical structure. It's not hard to imagine.

The object of the present invention is to provide a rotating anticathode X which eliminates the above-mentioned drawbacks.
To provide a wire device.

[Means for Solving the Problems] The present invention provides a hollow rotating anticathode with a cooling passage forming member that rotates together with the anticathode, the inner surface of the anticathode being an electron beam of the anticathode. A cooling liquid is circulated to a portion that will be the back surface of the irradiation section, while the cooling liquid will be applied to at least one of the portion that becomes the back surface of the electron beam irradiation section of the anticathode or the surface of the cooling passage forming member facing the portion. By forming a groove in the working liquid so as to have a velocity component opposite to the rotating direction of the rotating anticathode, the cooling liquid can be easily increased while not being adversely affected by shear stress of the cooling liquid and the like. It is possible to increase the flow rate of the cooling liquid. Specifically, the cooling liquid is circulated inside the hollow rotating anticathode rotatably supported in the vacuum container and the surface thereof is irradiated with an electron beam. By X-ray In the rotating anticathode X-ray device for producing the rotating anticathode, the rotating shaft of the rotating anticathode is formed in a hollow double-tube structure, and the cavity formed by the inner tube and the outer tube and the hollow portion of the inner tube are both described above. An inlet passage and an outlet passage for the cooling liquid are formed in communication with the hollow portion of the rotating anticathode, and a cooling passage forming member that rotates together with the rotating anticathode is provided inside the hollow portion of the rotating anticathode. A cooling passage is formed which circulates the cooling liquid flowing from the passage through the inner surface of the rotating anticathode, which is the back surface of the electron beam irradiation portion of the anticathode, and guides it to the discharge passage. A groove for allowing the cooling liquid to have a velocity component opposite to the rotating direction of the rotating anticathode on at least one of the portion of the back surface of the electron beam irradiation portion and the surface of the cooling passage forming member facing the portion. Shape It has a composition made.

[Operation] According to the above configuration, the cooling liquid flows into the inside of the rotating anticathode from the introduction passage of the cooling liquid, and passes through the cooling passage formed inside the rotating anticathode, and the electrons of the rotating anticathode are discharged. It reaches the part which becomes the back surface of the line irradiation part.

Since at least one of this portion or the cooling passage forming portion facing this portion is provided with a groove having a velocity component opposite to the rotating direction of the rotating anticathode, cooling reaching this portion is achieved. The working liquid has a velocity component with respect to the rotating anticathode and the cooling passage forming member in a direction opposite to their rotating direction.

Then, this velocity component is maintained in at least a part of the section in which the cooling liquid passes through the groove and reaches the discharge passage.

Considering this point from the viewpoint of the centrifugal force acting on the cooling liquid in the entire section of the cooling passage inside the rotating anticathode, the cooling liquid in the section up to the groove rotates at about the same speed as the rotating anticathode. On the other hand, on the other hand, the cooling liquid in the section from the groove to the discharge passage is rotating by the speed component.

Therefore, the centrifugal force acting on the cooling liquid in the section from the groove to the discharge passage is smaller by the difference in the rotation speed.

Therefore, the circulation of the cooling liquid is accelerated by the difference in the centrifugal force.

Moreover, since the cooling passage forming member inside the rotating anticathode rotates together with the rotating anticathode, there is no fixing member that causes shearing stress of liquid between the rotating anticathode and the anticathode. Unlike the conventional example, an unreasonable force is not applied to the inside of the rotating anticathode due to the rotation of the rotating anticathode, and the rotating torque is small.

[Embodiment] FIG. 1 is a partial sectional view showing an embodiment of the present invention.

In FIG. 1, reference numeral 1 is a vacuum container, and reference numeral 2 is a rotating anticathode rotatably supported in the vacuum container 1.

The rotating anticathode 2 has an outer cylinder portion 21 having a bottomed cylindrical shape,
The inner cylinder portion 23 is fitted in the outer cylinder portion 21 and forms a hollow portion 22 between the inner wall of the outer cylinder portion 21 and the inner wall.

A tubular rotary shaft 231 having a common central axis with the central axis of the outer tubular section 21 is formed in the inner tubular section 23 by extending the central section of the outer tubular section 21 to the right in the figure. .

The tubular rotary shaft 231 has a double tube structure, and the outer tube 2
An inner pipe 231b is coaxially arranged inside 31a, and a gap formed by the outer pipe 231a and the inner pipe 231b serves as an introduction passage 231c for a cooling liquid (for example, cooling water). The hollow portion of the inner pipe 231b has a discharge passage 231d for the cooling liquid.
It is said.

Further, the inner tube 231b is extended leftward in the figure to reach the hollow portion 22 of the rotating anticathode 2 , and further, in the hollow portion 22, the outer tubular portion 21 and the inner tubular portion 23 of the hollow portion 22. A cooling passage forming member 24 is formed so as to extend in a plate shape so as to partition an almost intermediate portion between the cooling passage forming member 24 and the cooling passage forming member 24.

The cooling passage forming member 24 divides the hollow portion 22 so as to guide the liquid introduced from the cooling liquid introducing passage 231c to a portion serving as the back surface of the electron beam irradiation unit 25 of the rotating anticathode 2 . Cooling passage 22a and the first cooling passage 22a
And a second cooling passage 22b that communicates with the cooling liquid and reaches the portion of the rotating anticathode 2 that is the back surface of the electron beam irradiation portion 25 to the cooling liquid discharge passage 231d.

Further, a groove 26 is formed on the back surface of the electron beam irradiation unit 25 so as to form an acute angle α in the counterclockwise direction with respect to the rotating direction of the anticathode 2 .

FIG. 2 is a partially developed view of the portion where the groove 26 is formed, as seen from the direction indicated by the line II-II in FIG.

In FIG. 2, the grooves 26 are substantially parallel to the back surface of the electron beam irradiation unit 25 at intervals of 1 to several mm so as to form an acute angle α in the counterclockwise direction with respect to the rotation direction R of the rotating anticathode 2. Multiple ridges with a generally triangular cross section (height of 1 to several mm)
Formed between 27. Note that FIG. 3 is a sectional view taken along line III-III in FIG.

Further, in the portion of the cooling passage forming member 24 facing the cooling passage 22b, that is, in the portion formed in parallel with the surface of the cooling passage forming member 24 orthogonal to the rotation axis 231 in FIG. A spirally formed groove 28 is provided which gradually decreases in diameter when tracing from the outer peripheral end portion in the direction opposite to the rotating direction R of the rotating anticathode 2 .

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1, in which the spiral groove 28 is formed on the surface of the cooling passage forming member 24 by a plurality of spiral protrusions 29 provided at regular intervals. It is formed between.

The rotating shaft 231 of the rotating anticathode 2 is the vacuum container.
1 is rotatably supported via a bearing 11, and a pulley 231e that is rotationally driven by an external drive device (not shown) is provided at the right end of the rotary shaft 231 in the drawing,
Further, a shaft seal 12 is provided on the vacuum side of the bearing 11, that is, on the left side portion in the drawing to maintain the vacuum.

An X-ray transmission window 13 is provided in a portion of the vacuum container 1 near the side of the electron beam irradiation unit 25 in the rotating anticathode 2 , and a beryllium (Be) foil or other material having excellent X-ray transmittance. The foil film 13a composed of is provided to maintain a vacuum.

Next, the operation of the rotating anticathode X-ray apparatus according to the above embodiment will be described.

First, while circulating the cooling liquid to said rotating anticathode 2, the pulley 231e rotating anticathode 2 rotationally driven by an external driving member (not shown) through, the electron beam irradiation section 25 of the rotating anticathode 2 When the electron beam e is irradiated, X-rays are generated from the electron beam irradiation unit 25, and the X-ray x can be taken out through the X-ray transmission window 13.

In this case, the cooling liquid introduced from the cooling liquid introduction passage 231c as shown by the arrow i in the drawing follows the respective paths indicated by the arrows j, k, l, m in the drawing to discharge the cooling liquid. The rotating anticathode 2 discharged from the passage 231d to the outside as shown by the arrow o and heated by the electron beam e is cooled.

At this time, until the cooling liquid reaches k from the path i, in particular, in a section extending from j to k is rotated together with the rotary anticathode 2, with velocity components with respect to the rotating anode 2 There is no such thing.

On the other hand, in the section from the path k to m, due to the action of the groove 26 and the groove 28, the cooling liquid has a velocity component opposite to the rotating direction of the rotating anticathode 2. .

Considering this point from the viewpoint of the centrifugal force acting on the cooling liquid, the centrifugal force acting on the section from the path j to k is larger than the centrifugal force acting on the section from the path k to m, and The difference in centrifugal force promotes the circulation of the cooling liquid flowing in the cooling passage 22.

 The above embodiment has the following advantages.

That is, by providing the groove 26, the cooling liquid can have a velocity component opposite to the rotating direction of the rotating anticathode 2 , and by providing the groove 28, the velocity component is not attenuated. Can be kept effective,
Therefore, the action of the centrifugal force promotes the circulation of the cooling liquid. Moreover, since the groove 26 is provided in the portion corresponding to the back surface of the electron beam irradiation unit 25, the surface area is large by that amount. As a result, the rotating anticathode 2 can be efficiently cooled.

The rotary anticathode 2 inside the cooling passage forming member 24 is rotated together with the rotary anticathode 2, fixing members such as to cause the shear stress of the liquid between the pair cathode 2 in the inside of the rotating anode 2 Therefore, unlike the above-mentioned conventional example, an unreasonable force is not applied to the inside of the rotating anticathode by the rotation of the rotating anticathode, and the rotating torque is small. As a result, the rotating anticathode 2 can be rotated at a higher speed to improve the allowable load, and at that time, there is no fear of vibration or damage.

Further, the rotating anticathode 2 is composed of the outer cylinder portion 21 and the inner cylinder portion 2
3, the cooling passage forming member 24, the outer tube 231a and the inner tube 231b of the tubular rotary shaft 231 are integrally formed, so that the mechanical structure has an extremely strong structure, and the design and Very easy to manufacture.

In the above embodiment, an example is shown in which a groove 26 is formed in the back surface of the electron beam irradiation unit 25 so as to form an acute angle α in the counterclockwise direction with respect to the rotating direction of the rotating anticathode 2. However, according to the present invention, as shown in a partial cross-sectional view of the rotating anticathode 2 in FIG. 5, the surface of the cooling passage forming member 24 facing the rear surface of the electron beam irradiating section 25 is The groove 26a may be provided so as to make an acute angle α with the rotating direction of the rotating anticathode 2 in the clockwise direction. In addition, FIG. 6 shows V in FIG.
FIG. 7 is a partial development view seen from the direction of the line I-VI, and FIG. 7 is a partial sectional view taken along the line VII-VII in FIG.

EFFECTS OF THE INVENTION As described in detail above, according to the present invention, a cooling passage forming member that rotates together with the anticathode is provided inside a hollow rotating anticathode so that the inner surface of the anticathode can be The cooling liquid is circulated to the site that becomes the back surface of the electron beam irradiation unit, and on the other hand, at least one of the site that becomes the back surface of the electron beam irradiation unit of the anticathode or the surface of the cooling passage forming member that faces the site. By forming a groove in the cooling liquid so as to have a velocity component opposite to the rotating direction of the rotating anticathode, the number of rotations can be easily increased without being adversely affected by shear stress of the cooling liquid. It is possible to increase the flow rate of the cooling liquid as well as the above, and thereby, the excellent effect that the allowable load can be remarkably increased is obtained.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an embodiment of the present invention, and FIG. 2 shows a portion where the groove 26 is formed, taken along line II-I in FIG.
FIG. 3 is a partially developed view when viewed from the direction indicated by the line I, FIG. 3 is a sectional view taken along the line III-III in FIG. 2, FIG. 4 is a sectional view taken along the line IV-IV in FIG. 1, and FIG. FIG. 6 is a partial sectional view taken along line VI-VI in FIG. 5, and FIG. 7 is a partial sectional view taken along line VII-VII in FIG. 5 showing another embodiment of the present invention. 1 …… Vacuum container, 2 …… Rotating anticathode, 22 …… Rotating anticathode 2
Hollow part, 22a ... first cooling passage, 22b ... second cooling passage, 231 ... rotating shaft, 231a ... outer pipe, 231b ... inner pipe, 2
31c ... Cooling liquid introducing passage, 231d ... Cooling liquid discharging passage, 24 ... Cooling passage forming member, 25 ... Electron beam irradiation part, 26, 26a ... Groove, 28 ... Spiral groove.

Claims (1)

(57) [Claims] 1. A rotating anticathode X-ray for generating an X-ray by circulating a cooling liquid inside a hollow rotating anticathode rotatably supported in a vacuum container and irradiating the surface with an electron beam. In the device, the rotating shaft of the rotating anticathode is formed in a hollow double-tube structure, and the void portion formed by the inner tube and the outer tube thereof and the hollow portion of the inner tube are both formed in the hollow portion of the rotating anticathode. An inlet passage and an outlet passage for the cooling liquid are formed to communicate with each other, and a cooling passage forming member that rotates together with the anticathode is provided in the hollow inside of the rotating anticathode to cool the cooling liquid flowing from the inlet passage. While forming a cooling passage that leads to the discharge passage by circulating a portion that is an inner surface of the rotating anticathode and is a back surface of the electron beam irradiation unit of the anticathode, and a back surface of the electron beam irradiation unit of the anticathode. Part or facing the part A rotating anticathode X-ray, wherein a groove for allowing a cooling liquid having a velocity component opposite to the rotating direction of the rotating anticathode to flow without resistance is formed on at least one of the surfaces of the cooling passage forming member. apparatus.