JPS61198537A - X-ray tube with rotary anode - Google Patents

Abstract

PURPOSE:To provide a rotary-anode X-ray tube having a vibration suppressing mechanism which produces a vibration suppressing effect as an oil film damper, is easy to mount and has a simple construction and a low cost, by supporting a bearing with a support and elastic rings each having a plurality of teeth oriented toward the axis of the ring and a groove defined between the teeth. CONSTITUTION:Elastic rubber rings 28, each of which has a U-shaped cross section and includes two teeth 22, a bottom 23 and a groove 27, are fitted in the openings of the support 29 of an X-ray tube. The tips of the teeth 22 are located in contact with the peripheral surface of a round bar 25 located at the end of a bearing box 6. The teeth 22 have numerous small holes 24, through which insulating foil 17 in a sealed container 8 enters into the groove 27. When a rotary body including the target, motor rotor, shaft, etc. of the X-ray tube performs a large vibration due to mechanical imbalance, the round bar 25 is vibrated through the bearing box 6. The capacity of the groove 27 is changed depending on the vibration to absorb it.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to improvements in rotating anode X-ray tube devices.

[Background of the invention]

FIG. 3 shows a conventional rotary anode X-ray tube device disclosed in Japanese Patent Application Laid-Open No. 57-78756. First, an outline of the overall structure will be explained according to FIG. 3. An anode target 2, which is an anode member, is fastened to one end of a drive motor rotor 3, which is a rotating member, and a shaft 4 is fastened to the other end. 4 is rotatably supported by two ball bearings 5 spaced apart from each other. The ball bearing 5 is mounted in a bearing box 6, and includes a part of the bearing box 6 and a bulb 12, an anode target 2, a cathode body 1 facing the anode target 2, a motor rotor 3, a shaft 4, and a ball bearing 5. An X-ray tube is constructed by covering these members in a vacuum. Further, this X-ray tube is fixed in a closed container B filled with insulating oil 17. That is, a rotating magnetic field generating bag f for driving the motor rotor 3 is provided at one end of the closed container 8.
A frame 13 is provided to support t7, and a thin elastic plate 16 is fixed to the frame 13 with a retaining ring 15. A bearing box 6 is fastened to one center of the elastic plate 16, and a movable body 19 is fastened to the other. has been done. Further, a so-called oil film damper 21 is provided on the outer periphery of the movable body 19, in which a ring 18 is disposed with a minute gap 20 filled with oil. Note that 21a and 12b are holes provided in the frame 13 and the elastic plate 16 for insulating oil to flow in.

In such a configuration, an electron beam is emitted from the cathode body 1 to the rotating anode target 2 to generate X-rays in the direction of the arrow, but in this case, the anode target 2 is heated to about 1000C, The ball bearing 5 that supports this is also 5
The temperature will be about 0.00 [.

For this reason, the anode target 2, motor rotor 3 and shaft 4
The axis of the rotating body, which is composed of several components, is slightly eccentric due to thermal deformation and damage of each element, and mechanical misalignment occurs, resulting in large vibrations during rotation, especially when the shaft system passes through critical speeds. However, the oil film damper 21 causes p
Vibration is suppressed.

This damper 21 utilizes the squeezing action of oil, and its distribution effect is extremely good, resulting in stable rotation and ball←1 (receiver 5).
However, improvements are needed in terms of simpler structure, lower cost, and easier installation and adjustment.

[Object of the Invention] The present invention focuses on the above-mentioned improvements, and provides a rotary positive Jl'li X-ray tube device that has a vibration damping effect as an oil film damper, has a simple structure, is low in cost, and is easy to install. The purpose is to provide

[Summary of the invention]

In the present invention, an elastic ring having a U-shaped cross section is inserted between a bearing box and a support body, and the space formed by the opening of the elastic ring and the outer periphery of the bearing box is completely filled with oil. The chisel performs elastic action and oil squeezing action.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A further embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a partial cross-sectional view of a rotating anode X-ray tube device according to the present invention.
Components in the figure that are the same as those in FIG. 3 are given the same reference numerals, and their explanation will be omitted, and only the different parts will be explained. Note that the X-ray tube has the same structure as the conventional one.

Support body 29 fixed to frame 13 with presser ring 15
A rubber thermal elastic ring 28 having a U-shaped cross section and consisting of two teeth 22, a bottom 23, and a groove 27 formed by them is fitted into the opening recess. elastic ring 2
8 is arranged such that the tip of its rim 22 comes into contact with the outer periphery of the cylindrical rod 25 at the end of the bearing box 6. The toothed portion 22 of the elastic ring 28 is provided with a large number of small holes 24 passing through the toothed portion 22. In this case, since the insulating oil 17 is sealed in the airtight container 8, the oil 17 flows from the small hole 24 to the groove 27 and the cylindrical rod 2.
It gets into the gap formed between 5 and 5.

When the rotating body composed of the target 2, motor rotor 3, shaft 4, etc. vibrates greatly due to mechanical misalignment, the cylindrical rod 25 also vibrates via the bearing box 6. Therefore, the tooth portion 22 of the elastic ring 28 also deforms and vibrates due to its own elasticity.

For this reason, the volume within the groove 27 also changes in response to the imaging, and therefore a pressure change occurs within the groove 27, causing the oil within the groove 27 to move in the axial and circumferential directions, further increasing the small hole 24 and the tooth. Part 22
Since the breathing action of oil also occurs in the minute gap at the contact portion between the cylinder rod 25 and the cylinder rod 25, the vibration energy becomes thermal energy and is dissipated.

The vibration damping effect due to this so-called squeeze effect effectively suppresses the vibration transmitted from the rotating body to the bearing box 6, and therefore the vibration of the rotating body such as the anode target 2 due to unbalance is also reduced. Dynamic loads acting on 5 are also reduced. In this case, the elastic ring 28
If the number of tooth portions 22 is set to two or more, the vibration damping effect of the oil becomes even greater.

FIG. 2 shows another embodiment of the present invention, and shows the positional relationship between the bearing box 6 and the closed container 8, that is, the positional relationship with the outlet 30 of the X-rays generated from the anode target 2 from the closed container 8. The cylindrical rod 25 is provided with a large diameter part 26 in order to maintain the bearing box 6, and the teeth 22'f of the elastic ring 28 are inserted into this large diameter part 26 to prevent the bearing box 6 from moving in the axial direction. It is something. In this embodiment, since the oil pressure in the groove 27 changes even when the large diameter portion 26 vibrates in the 60 directions, there is a damping effect not only in the radial direction but also in the axial direction.

As described above, the present invention is characterized in that a single elastic ring can simultaneously perform an elastic action and an oil squeeze photography action. In general, rubber members have a large internal damping effect, so they are widely used as elastic supports aiming at vibration damping effects, but in the present invention, as described above, in addition to the vibration damping effect of the rubber itself, the rubber member has a large internal damping effect. Since a highly effective oil film damper is formed, the vibration suppression effect is significantly increased.

Although a rubber member is used as the elastic ring in each of the embodiments of the present invention, it is of course possible to use any elastic material such as nylon, vinyl, II/fz, etc.

〔Effect of the invention〕

According to the present invention, an oil film damper with a large vibration damping effect can be formed by simply fitting a grooved rubber ring between the bearing box and the sealed container. A rotating anode X-ray tube device can be realized.

[Brief explanation of the drawing]

1 and 2 are partial sectional views of embodiments of a rotating anode X-ray tube device according to the present invention, and FIG. 3 is a longitudinal sectional view showing a conventional rotating anode X-ray tube device. 2... Anode target, 3... Motor rotor, 4...
... Shaft, 5... Ball bearing, 17... Insulating oil, 22...
・Tooth portion, 24...Small hole, 25...Cylindrical rod, 26...
・Large diameter part, 27...Groove part, 28...Elastic ring, 2
9...Support. 1st anti-2nd figure

Claims (1)

[Scope of Claims] 1. An anode target disposed to face the cathode body, a rotating member integrated with the anode target, a bearing device that rotatably supports this rotating member, a part of this bearing device, and a container. A rotating anode A rotating anode in a wire tube device, characterized in that the bearing device is supported via a support by an elastic ring having a plurality of teeth facing toward the center and a groove formed by the teeth. X-ray tube equipment. 2. The rotating anode X-ray tube device according to claim 1, wherein the teeth of the elastic ring have a large number of small holes passing through the teeth. 3. The rotating anode X-ray tube device according to claim 1, wherein the bearing device is provided with a large diameter portion, into which the groove of the elastic ring is fitted.