KR20190080801A - Miniature X-ray tube - Google Patents

Abstract

The present invention relates to a small X-ray tube, which comprises: a filament for emitting electrons when voltage is applied; a base for fixing the filament and having two filament through-holes to connect power to both poles of the filament; a cylindrical extractor closely attached to the base, and surrounding the filament without being in contact with the filament; a cutoff voltage providing unit for applying the cutoff voltage between the extractor and one of the poles of the filament; a target for receiving the electrons emitted from the filament, and emitting X-rays; a body of a ceramic material, having the filament connected to one side thereof and a target connected to the other side thereof to allow a gap between the filament and the target to be in a sealed state; an extraction pipe for extracting air inside the body by penetrating the target to form the same in a vacuum state; and a cap closely attached to the target at the opposite of the body, and surrounding an end of the extraction pipe.

Description

Miniature X-ray tube

The present invention relates to a compact x-ray tube, and more particularly, to a compact x-ray tube capable of minimizing radiation exposed to a body to be photographed using a compact x-ray tube which can be inserted into the body.

Of the techniques for diagnosing a patient's disease, X-ray technology, which can capture the inside of a patient's body, is becoming widespread. Particularly in the past, due to the size of the X-ray imaging apparatus, it was possible to photograph only a large area such as a chest, an arm, a leg, etc. In the dental treatment and the like, x- have.

The prior art Korean Patent No. 10-1915523, "X-ray tube", describes the basic shape of such a compact X-ray tube. When electrons are emitted from the emitter, electrons collide with the anode electrode to emit X-rays Respectively.

However, when X-rays are generated in such a manner, there is a problem that electrons are generated in the emitter and high heat is generated in the process of electrons colliding with the electrodes and X-rays are generated, resulting in damage to the device or inefficiency .

In addition, it is difficult to emit the same level of x-rays in all directions of emission of the x-rays, no matter how uniform x-rays are emitted when the x-rays are emitted from the x-ray tube, have.

Thus, by efficiently discharging the heat generated from the compact X-ray tube to the outside, it is possible to increase the lifetime of the X-ray apparatus and improve the performance thereof, and to uniformly radiate the X- A technique for minimizing the unnecessary exposure to radiation is required.

Korean Patent No. 10-1915523

It is an object of the present invention to provide a small x-ray apparatus and to facilitate x-ray imaging of a small area.

SUMMARY OF THE INVENTION The present invention aims at maximizing the efficiency of heat emission from compact x-ray tubes that generate x-rays.

In addition, the present invention aims at facilitating heat shrinkage by filling the space between the body and the sleeve in the X-ray tube with oil.

In addition, the present invention aims to prevent the arching effect from being generated by the pointed portion by pinching off the extraction tube with the cap to surround the sharp portion generated.

According to an aspect of the present invention, there is provided a compact X-ray tube, comprising: a filament that emits electrons when a voltage is applied; a target that receives electrons emitted from the filament and emits an X-ray; A body of ceramic material connected to the other side of the target to seal the space between the filament and the target, an extraction pipe for extracting the air inside the body through the target to make it into a vacuum state, And a cap surrounding the end of the extraction tube.

Further, it may further comprise a connection part between the body and the target in the form of a ring, the ceramic part constituting the body, and the connection part made of a metal having a thermal expansion coefficient within a predetermined range.

At this time, the connection portion may be formed of a kovar.

At this time, the cap may be made of a metal material, and may be configured to form a plurality of wrinkles on the outer wall to discharge heat generated from the target to the outside.

It is also possible to further include a sleeve which surrounds both the body and the cap, and the inner space of the sleeve may be configured to fill up with oil.

According to the present invention, it is possible to obtain an effect of facilitating X-ray imaging of a small area by providing a compact X-ray device.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to obtain an effect of maximizing the efficiency of heat emission generated in a compact X-ray tube generating an X-ray.

Further, according to the present invention, the space between the body and the sleeve in the X-ray tube is filled with oil, so that the effect of facilitating the heat radiation can be obtained.

Further, according to the present invention, it is possible to obtain the effect of preventing the arcing effect from being generated due to the pointed portion by pinching off the extraction tube with the cap to surround the sharp portion generated.

1 is a view showing a configuration of a compact x-ray tube according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating in detail a portion where an X-ray is emitted from a compact X-ray tube according to another embodiment of the present invention.
FIG. 3 is a view showing a window portion where an X-ray is emitted in a compact X-ray apparatus according to an embodiment of the present invention.
4 is a view showing an example of a planarization filter of a compact x-ray apparatus according to an embodiment of the present invention.
FIG. 5 is a block diagram illustrating a voltage application module of a compact X-ray tube according to an exemplary embodiment of the present invention. Referring to FIG.
6 is a diagram illustrating the operation of a compact X-ray tube according to an embodiment of the present invention.
Figure 7 is a more detailed view of a portion associated with a heat release cap in a compact x-ray tube in accordance with an embodiment of the present invention.
8 is a view showing an example of a heat radiation cap of a compact x-ray tube according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. Further, in describing the embodiments of the present invention, specific numerical values are merely examples and the scope of the invention is not limited thereby.

1 is a view showing a configuration of a compact x-ray tube according to an embodiment of the present invention.

The filament 101 emits electrons when a voltage is applied. The filament 101 is heated by applying electricity, and when it exceeds a certain temperature, it starts to emit electrons. The compact x-ray tube according to the embodiment of the present invention rapidly moves the electrons emitted from the filament 101 toward the target 102 by using a high voltage between the filament and the target 102, And collides with the target 106 to generate x-rays.

A portion that functions to generate electrons such as the filament 101 is called an emitter or a cathode and is not limited by such a term and may function as a filament 101). ≪ / RTI >

As described above, the filament 101 generates heat by electricity, and when the heat exceeds the critical point, the filament 101 emits electrons. Therefore, a preheating period is required to preheat the heat until the temperature becomes a certain temperature or more. Therefore, in the conventional X-ray tube, there is a problem that the inspectors or patients are exposed to the X-rays of a dose which is insufficient for capturing the X-ray image until the power is applied and the preheating of the filament is completed.

Since the filament 101 operates when a voltage is applied, it is obvious that a power supply module for applying a voltage to the filament is connected, and the X-ray imaging can be controlled by supplying and blocking power through the power supply module .

The target 102 is connected to the other end of the body 105 and receives electrons emitted from the filament 101 to emit x-rays. It is preferable that the target 106 is made of a metal material such as copper. If electrons moving at a high speed due to high voltage collide with a metal surface, x-rays may be generated and X- have.

The target 102 is also referred to as an anode. When the electrons emitted from the filament 101 collide with each other, as shown in the drawing, the target 102 is tilted in a direction in which the x- Can be configured to be released. Depending on the structure of the target 106, the inclination, the material, etc., it is possible to have different X-ray emission patterns for the same electrons and have different structures depending on the application method of X-rays and the like.

The filament 101 is connected to one side of the body 103 and the target is connected to the other side 102 to seal the space between the filament and the target. The inside of the X-ray tube is vacuumed so that electrons can move without being disturbed. To this end, a body 103 including the filament 101 and the target 102 and covering the entire X-ray tube is required.

Since the electrons move inside the body 103 and the x-rays are emitted, the body 105 is preferably made of a ceramic material so that a high voltage applied without affecting the movement of the electrons can be insulated. It is preferable to use a material having a thermal expansion coefficient similar to that of the ceramic material, such as a kovar, to contact the body 103 of the ceramic material.

The extraction tube 104 penetrates the target and extracts the air inside the body 103 to make it in a vacuum state. The filament 101 and the target 102 may be coupled to the body 103 and then the body 103 may be vacuumed so that the body 103 is not disturbed by the movement of the electrons. 103) The inside air must be extracted. To this end, an extracting tube 104 for extracting air is required. If the extracting tube is located anywhere inside the body 103, the shape of the sharp tube hinders the movement of electrons, and arching phenomenon occurs And it may be difficult to generate x-rays in a desired shape.

Accordingly, the extraction tube 104 is disposed in such a manner that the extraction tube 104 can penetrate the target 102 and extract the air inside the body 103. The extraction tube 104 is disposed at a position where electrons emitted from the filament 101 reach the target 102 It is possible to constitute the T-shape as shown in the drawing, and to suck air from the left and right sides of the target 102 and to draw it backward. With such a configuration, it is possible to suck air without causing any problem in the process of electrons emitted from the filament 101 reaching the target 102.

The shape of the extraction tube 104 is not limited to this form and it is possible to extract the air inside the body 103 to the outside without affecting the electron impacting the target 102 as described above Anything that can be done is possible.

The cap 105 is in close contact with the target on the opposite side of the body 103 and surrounds the end of the extraction tube 104. When electrons generated in the filament 101 move to the target 103, if there is a pointed portion in the periphery, arching may occur and electrons may move in a direction different from the intended direction. The extraction tube 104 is used to extract the air inside the body 103 when the x-ray tube is manufactured, and then sealed so that no air is introduced again. This sealing is referred to as pinch-off .

In the process, when the pinch-off process for cutting and sealing the end of the extraction pipe 104 is performed, the tip of the extraction pipe is forced to be pointed out, which may cause arching phenomenon. Accordingly, the cap 105 can be positioned behind the target 102, as shown in the drawing, to surround the pinch-off end portion of the extraction pipe 104, thereby preventing such a phenomenon in advance.

Further, the cap 105 is closely attached to the target 102 to emit heat. As described above, electrons generated in the filament 101 reach the target 102 and collide with each other, thereby generating x-rays. In this process, heat is generated due to the collision effect. Especially when a compact x-ray device, not a large x-ray device, emits a high energy x-ray, a lot of heat is generated in a narrow target area, which may cause deformation of the device or affect performance.

Accordingly, the cap 105 is connected to the target 102 where a lot of heat is generated, and serves to rapidly discharge the heat of the target 102. For this purpose, it is preferable that the cap 105 is made of a metal material having high electrical conductivity, and the outer surface of the cap 105 is formed with wrinkles, thereby maximizing an area for emitting heat, .

The cap 105 may preferably be made of the same material as the target to quickly release the heat of the target 103, and a metal such as copper that facilitates x-ray emission may be used as the material.

The connection part 106 is attached between the body 103 and the target 102 in the form of a ring and is composed of a ceramic constituting the body 103 and a metal having a thermal expansion coefficient within a predetermined range. As described above, the body 103 is preferably made of a ceramic material, and the target 102 connected to the other side of the body is made of a metal material such as copper that can easily radiate x-rays. When the ceramic and copper are directly connected , There is a high possibility that the device is damaged in the process of moving between the high temperature and the low temperature due to the difference in thermal expansion coefficient between the ceramic and the copper.

Therefore, it is possible to arrange the connecting portion 106 in the middle without directly connecting the body 103 and the target 102. In this case, a kovar having a thermal expansion coefficient similar to that of the ceramic constituting the body 103, The damage caused by heat is not generated between the body 103 and the connecting portion 106 and the possibility that the connecting portion 106 and the target 102 are damaged due to metal is low, . Kovar is an alloy of Fernico type alloy with Fe 54%, Ni 29% and Co 17% composition and has a thermal expansion coefficient similar to that of hard glass and is widely used in sealing parts with glass or ceramics Is the material.

Sleeves 107 and 108 enclose both the body 103 and the cap 105. As shown in the figure, the sleeve that encloses both the body 103 and the cap 105 can be composed of the polymer sleeve 107 and the lead sleeve 108. Since a high voltage is applied to the inside of the sleeve 103, In order to prevent exposure to unnecessary x-rays, the film is wrapped with lead having excellent radiation shielding performance so as to obtain both the effects of insulation and radiation shielding .

Due to the shielding effect due to the lead sleeve 108, a window through which the x-ray can be transmitted must be formed in the sleeves 107 and 108 in order to transmit the generated x-rays to a necessary place. In the x- So that x-ray exposure can be minimized.

The internal spaces of the sleeves 107 and 108 can be filled with oil, which is non-polar and can quickly cool high temperature heat generated in the x-ray tube without draining the electricity generated in the x- have. This makes it possible to provide a safer and more durable x-ray tube.

FIG. 2 is a diagram illustrating in detail a portion where an X-ray is emitted from a compact X-ray tube according to another embodiment of the present invention.

1, the filament 101, the target 102, the body 103 and the cap 105 are made according to the description of Fig. 1, and the shape of the extraction tube 104 is T The target 102 is not sucked from the left and right sides of the target 102 but the both ends of the T are bent again so that suction can be performed toward the filament 101. In the center portion of the target 102, It is not affected when this happens.

1 can be applied to a structure in which the target 102 is narrow and protruding. Since the portion to be sucked in air is toward the filament 101, it may be difficult to suck, whereas in the example of Fig. 2 A tube is formed in the direction of the filament 101, which makes it easier to suck, but there is a disadvantage that the tube is folded once more. Thus, the extraction tube 104 can be implemented in various forms.

2, an extractor 109 is additionally described, in which the extractor 109 does not contact the filament 101 and surrounds the filament. The extractor is made of metal and surrounds the filament 101, which can affect the movement of electrons when the filament 101 emits electrons. Therefore, it can be determined at which position of the target 102 the emitted electrons are to be focused according to the inner inclination of the extractor 109, the size of the hole, and the like.

Therefore, by adjusting the shape of the extractor 109, the shape in which the x-rays are generated can be implemented differently, and the sharpness of the x-ray image can be increased by concentrating the focus area.

Particularly, since the extractor 109 is not in contact with the filament 101, when a voltage is applied between the filament 101 and the extractor 109, an electric field is generated in the space between the filament 101 and the extractor 109. Using this electric field , Electrons generated in the filament 101 can be prevented from being emitted to the outside, and x-ray emission from the target 102 can be prevented. As described above, after the filament 101 has exceeded the threshold temperature, electrons are emitted in earnest and the preheating time is required. In the conventional technique, electrons generated little by little during the preheating time collide with the target and x-rays are generated , There is a problem that an unnecessary x-ray may be exposed to an inspector or a patient. In the present invention, if an electric field is generated by applying a cutoff voltage between the extractor 109 and the filament 101 as described above, It is possible to control the X-ray to occur only at the moment.

The extractor 109 must be made of a metal material in order to apply a high voltage. As shown in the drawing, the extractor 109 must be in close contact with the body 103 made of a ceramic material to make the internal space vacuum, Considering the characteristics of the X-ray tube, it is preferable to use a material having a thermal expansion coefficient similar to that of the ceramic in order to prevent an impact from being generated due to a difference in thermal expansion coefficient during heating. As mentioned above, there is a kovar.

As described above, the end portion 110 of the extraction tube 104 is configured to seal the extraction tube 104 after the air extraction is completed. As shown in the drawing, the tip portion 110 is sharpened, and arching phenomenon There is a possibility of occurrence. Therefore, it is preferable that the cap 105 is wrapped around it so that a sharp point is not exposed.

FIG. 3 is a view showing a window portion where an X-ray is emitted in a compact X-ray apparatus according to an embodiment of the present invention.

In the drawing, the area indicated by e is the window and the area indicated by f corresponds to the flattening filter. As shown in the figure, depending on the angle at which the X-ray is emitted, the flattening filter has a slope close to vertical at the center part, And a slope inclined in the corresponding direction toward the right end.

By forming the thickness in accordance with the direction in which the X-rays pass through the respective regions of the flattening filter, the X-rays passing through one region are allowed to pass through the filter in the corresponding region, More accurate planarization can be achieved.

4 is a view showing an example of a planarization filter of a compact x-ray apparatus according to an embodiment of the present invention.

As shown in the figure, the planarization filter is composed of a plurality of regions, and the thicknesses of the planarization filters may be different from each other. The planarization filter of this figure is configured to have the thickest central portion to make a lot of x-ray attenuation, and it can be seen that the left side portion is relatively thicker than the left side portion.

Also, it can be seen that the thickness of each region is not formed in the vertical direction but has an angle inclined according to the emitting direction of the X-rays passing through the respective regions, and is not inclined only in the lateral direction as shown in FIG. 2 , And the inclination is increased toward the edge in all directions with respect to the center point, so that it is possible to match the emitting direction of the actual x-ray.

5 is a block diagram illustrating a voltage application module of a compact X-ray tube according to an embodiment of the present invention.

As shown in the drawing, a compact X-ray tube according to the present invention basically comprises a filament heated by a voltage of a filament power supply part for applying a voltage to a filament, and electrons generated in the filament are moved in a target direction.

At this time, a high voltage difference is formed between the filament and the target due to the filament high voltage providing part and the target high voltage providing part, and the target becomes the anode so that the electrons generated from the filament move quickly in the target direction. The voltage formed between the filament and the target 106 can be as high as about 70 kV, depending on the use of the x-ray.

The present invention includes a cutoff voltage providing unit for adding a voltage to the extractor to apply a cutoff voltage between one pole of the filament and the extractor to prevent electrons generated in the filament from moving toward the target, .

6 is a diagram illustrating the operation of a compact X-ray tube according to an embodiment of the present invention.

As shown in the figure, when the voltage is applied to the filament, it takes time to preheat until the temperature of the filament reaches a temperature at which heating is started and electrons are emitted. As shown in the drawing, a preheating time of 2 seconds is required. At this time, a small amount of electrons may be emitted, which may unnecessarily cause the x-rays to be emitted.

It may take time for the high voltage between the filament and the target to reach the target voltage, and there has been no method for blocking the unnecessary X-rays generated in this process. However, when the cut-off voltage is applied to the extractor as in the case of the X-ray tube according to the present invention, the emission of electrons can be precisely controlled based on the cut-off voltage, thereby enabling the system to emit the X- It is possible to do.

Figure 7 is a more detailed view of a portion associated with a heat release cap in a compact x-ray tube in accordance with an embodiment of the present invention.

As shown in the figure, the cap 105 is configured to surround a sharp portion of the end portion of the extraction tube 104. [ As described above, arcing or the like occurs when a pointed portion occurs due to the pinch-off, so that electrons are prevented from moving as desired. Therefore, it is necessary to cover the capping as much as possible. I will do the same.

1 shows an example in which a T-shaped extraction pipe is formed, and between the target 102 made of copper (Cu) and the body 103 made of ceramic (Al 2 O 3) It can be seen that the connection part made of kovar is located.

8 is a view showing an example of a heat radiation cap of a compact x-ray tube according to an embodiment of the present invention.

As shown in the figure, the cap 105 may serve to discharge heat generated by collision of electrons in the target 102 to the outside. In order to discharge heat more effectively, The larger the surface area to meet, the better. Therefore, as shown in the drawing, the rear portion of the cap 105 may be formed in a wrinkled shape, and any shape can be applied as long as the surface area can be widened.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

101: filament 102: target
103: Body 104: Extraction tube
105: cap 106:
107, 108: Sleeve

Claims (1)

A filament that emits electrons when a voltage is applied;
A base including two filament through holes for fixing the filament and connecting power to both poles of the filament;
A cylindrical extractor in close contact with the base and surrounding the filament without contacting the filament;
A cutoff voltage supplier for applying a cutoff voltage between one of the poles of the extractor and the filament;
A target that receives electrons emitted from the filament and emits an x-ray;
A body of a ceramic material which has a filament connected to one side and a target connected to the other side to seal the filament and the target;
An extracting pipe for extracting the air inside the body through the target to make it into a vacuum state; And
A cap which is in close contact with the target on the opposite side of the body and surrounds the tip of the extraction tube,
A compact x-ray tube comprising:

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