JPH07327973A - X-ray ct apparatus - Google Patents

Abstract

PURPOSE:To provide an X-ray CT apparatus which permits high-speed scanning and makes it possible to obtain diagnostic images having high image quality with high cooling efficiency and less temp. rise and change within an apparatus body. CONSTITUTION:This X-ray CT apparatus has a rotating section frame 2 which is freely turnably arranged in an apparatus body casing 1, an X-ray tube 3 which is integrally mounted at the rotating section frame 2 and a cooler 6a which feeds and discharges a refrigerant medium to and from the X-ray tube 3 via cooling pipings 5a, 5b and cools the X-ray tube 3. This cooler 6a is arranged in the fixing section of the apparatus body. A universally turnable pipe joint 10 is interposed between the cooling pipings 5a and 5b for connecting the X-ray tube 3 and the cooler 6a. The cooler 6a is preferably arranged in the fixing section on the outside of the apparatus body casing 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray CT apparatus,
In particular, the present invention relates to an X-ray CT apparatus capable of high-speed scanning, high cooling efficiency, and capable of obtaining a high-quality diagnostic image with little temperature rise or change in the apparatus body.

[0002]

2. Description of the Related Art An X-ray CT apparatus (X-ray CT scanner) is
Generally, as shown in FIG. 3, a rotating part frame 2 rotatably arranged in the apparatus main body casing 1, an X-ray tube 3 integrally mounted on the rotating part frame 2, and an X-ray tube 3 facing each other. Detector 4 mounted at rotating frame 2 position
And a cooling medium (cooling oil) through the cooling pipe 5 to the X-ray tube 3
Cooler (oil cooler) 6 that supplies and discharges to and from the X-ray tube 3
And is configured.

At the time of diagnosis, a patient as the subject 7 is placed in the exposure area of the X-ray tube 3, and the X-ray tube 3 emits X-rays while rotating the rotating part frame 2 so that the subject 7 can be exposed. The intensity of the X-ray transmitted through the detector is detected by the detector 4, and the detection data is processed by a computer to reconstruct a sliced tomographic image.

Further, if the X-ray tube 3 is continuously used for a long time, the temperature rise becomes large and exceeds the rating, so that the X-ray tube 3 is forcibly cooled by the cooler 6. The cooler 6 includes a cooling fin 8 and a cooling fan 9, and the X-ray tube 3 and the cooler 6
Are connected by two cooling pipes 5 on the high temperature side and the low temperature side, and the X-ray tube 3 is cooled by circulating the cooling oil cooled by the cooling fan 8 and the cooling fan 9. The cooler 3 is conventionally fixed to the rotating part frame 2 and
It is configured to rotate integrally with the wire tube 3.

[0005]

However, in the above-mentioned conventional X-ray CT apparatus, since the cooler and its auxiliary equipment are integrally fixed to the rotating part frame, the weight of the rotating part frame becomes large. However, there is a problem that it is not suitable for high speed rotation and it becomes difficult to set a high scan speed. In addition, since the inertial force of the entire rotary unit frame becomes large, it is necessary to increase the size of driving equipment and braking equipment, which causes a problem of increasing manufacturing cost.

On the other hand, since the cooler is arranged in the closed space in the casing of the main body of the apparatus and has a structure in which the exhaust heat from the cooling fins is released into the main body of the apparatus, the cooling efficiency of the X-ray tube is low and the Due to changes in radiation exposure conditions, temperature rises and changes within the device are likely to occur, which causes variations in the detection data in the detector, which deteriorates the image quality of the diagnostic image, and the electronic components for control and calculation that are installed in the device. There is a problem that the life and reliability are likely to decrease.

The present invention has been made in order to solve the above problems, and is capable of high-speed scanning, high cooling efficiency, and a high-quality diagnostic image with little temperature rise or change in the apparatus body. It is an object of the present invention to provide an X-ray CT apparatus capable of performing the above.

[0008]

In order to achieve the above object, an X-ray CT apparatus according to the present invention comprises a rotary frame rotatably arranged in a casing of a main body of the apparatus, and an integral body of the rotary frame. In an X-ray CT apparatus comprising an X-ray tube mounted on an X-ray tube and a cooler for cooling and cooling the X-ray tube by supplying / discharging a refrigerant medium to / from the X-ray tube via a cooling pipe, the cooler is fixed to a device body. And the rotatable pipe joint is interposed in the cooling pipe connecting the X-ray tube and the cooler. In particular, it is preferable to arrange the cooler at a fixed portion outside the apparatus main body casing.

[0009]

According to the X-ray CT apparatus having the above structure, since the cooler is arranged on the fixed portion of the apparatus main body without being fixed to the rotating portion frame, the weight of the entire rotating portion frame is reduced and the rotating portion Compact structure. Therefore, the rotating operation of the rotating unit is facilitated and high-speed scanning becomes possible.

Further, by disposing the cooler in the fixed portion outside the apparatus main body casing, the cooler can be increased in size without being restricted by the weight limitation of the rotating portion, and the cool air outside the main body of the apparatus can be used as intake air of the cooler. Since it can be used, the cooling efficiency of the X-ray tube can be significantly increased. Furthermore, since high-temperature exhaust heat from the cooler is released to the outside of the device body casing, the temperature rise and temperature change inside the device body are reduced,
Regardless of the frequency of scanning, the temperature inside the apparatus main body is stable, a high-quality diagnostic image can be obtained, and the operational reliability of the apparatus can be greatly improved.

[0011]

An embodiment of the present invention will now be described with reference to the accompanying drawings. FIG. 1 is a side sectional view showing an embodiment of the X-ray CT apparatus according to the present invention. The same components and parts as those of the conventional device shown in FIG. 3 are designated by the same reference numerals.

That is, the X-ray CT apparatus according to this embodiment is
A rotary medium frame 2 rotatably arranged in the apparatus main body casing 1, an X-ray tube 3 integrally attached to the rotary frame 2, and a cooling medium 5a, 5b are used to transfer the refrigerant medium to X-rays. In an X-ray CT apparatus equipped with a cooler 6a for supplying / discharging the tube 3 and cooling the X-ray tube 3, the cooler 6a is arranged at a fixed portion outside the apparatus main body casing 1, and the X-ray tube 3 And cooling pipes 5a, 5 that connect the
It is configured by interposing a rotatable pipe joint 10 in b.

Further, the rotatable pipe joint 10 is provided with a rotating trough 11 in which a flow path for cooling oil as a cooling medium is formed.
And the fixed-side trough 12 are fluid-tightly and rotatably fitted to each other via a seal member 13. The rotating trough 11 has a flow path 14a for circulating the low temperature side cooling oil.
And an annular flow path 14b for circulating the high temperature side cooling oil
And are formed concentrically, and are supported by a bracket protruding from the rotating unit frame 2. On the other hand, the fixed side annular trough 12 is configured by concentrically forming a flow path 15a for circulating the low temperature side cooling oil and an annular flow path 15b for circulating the high temperature side cooling oil. It is supported by a fixed portion such as the casing 1. In the rotatable pipe joint 10 according to the present embodiment, the central axis thereof is the rotating part frame 2
Device main body casing 1 so that it coincides with the rotation center axis C of
Is located on the side surface of the.

In the X-ray CT apparatus configured as described above, the cooling oil cooled by the cooling fins 8 and the cooling fan 9 of the cooler 6a passes through the low temperature side cooling pipe 5a by the circulation pump 16 and the rotatable pipe joint. It is fed to the fixed trough 12 of 10. Further, the supplied low temperature side cooling oil flows into the rotary side trough 11, passes through the low temperature side cooling pipe 5a and flows into the X-ray tube 3, and cools the X-ray tube 3. The high-temperature side cooling oil that has exchanged heat with the X-ray tube 3 and is heated is sequentially cooled through the high-temperature side cooling pipe 5b, the rotary side trough 11 and the fixed side trough 12 of the rotatable pipe joint 10, and the high temperature side cooling pipe 5b. Bowl 6
It is returned to a, cooled again by the cooling fin 8 and the cooling fan 9, and circulated by the circulation pump 16.

According to the X-ray CT apparatus according to the above embodiment,
Since the rotatable pipe joint 10 is interposed in the cooling pipes 5a and 5b for circulating the cooling oil from the cooler 6a to the X-ray tube 3, even when the rotating part frame 2 having the X-ray tube 3 rotated, It is possible to smoothly circulate the cooling oil without causing twists or the like in the cooling pipes 5a and 5b.
The wire tube 3 can be cooled efficiently.

Further, since the cooler 6a is not fixed to the rotating part frame 2 but is arranged on the fixed part outside the apparatus main body casing 1, the weight of the rotating part frame 2 as a whole is reduced and the structure of the rotating part is made compact. To do. Therefore, the rotating operation of the rotating unit is facilitated and high-speed scanning becomes possible.

Further, the cooler 6a is connected to the apparatus main body casing 1
Since the cooler 6a can be made larger without being restricted by the weight limit of the rotating part and the cool air outside the main body of the device can be used as the intake air of the cooler 6a, the X-ray tube 3 The cooling efficiency of can be significantly increased. Furthermore, since the high-temperature exhaust heat from the cooler 6a is released to the outside of the device body casing 1, the temperature rise and temperature change in the device body are reduced, and the temperature in the device body is stabilized regardless of the scan frequency. A high-quality diagnostic image can be obtained, and the operational reliability of the device can be significantly improved.

Since the characteristics of the detector 4, which is particularly sensitive to temperature changes in the apparatus body, can be stabilized, a high-quality diagnostic image with little disturbance can be obtained. Further, since the temperature rise in the apparatus body is effectively suppressed, the life of the electronic components for control calculation arranged in the apparatus body is not shortened, and C
The durability and reliability of the T device can be significantly improved.

Further, since the cooling efficiency of the X-ray tube can be remarkably enhanced, the temperature of the X-ray tube does not excessively rise even if the X-ray CT apparatus is continuously used for mass examination for a long time. Further, even if the temperature rises excessively, the waiting time for cooling (waiting for OLP) required for the X-ray tube temperature to drop to a predetermined value is shortened. Therefore, X-ray C
It is possible to smoothly carry out the group medical examination work by the T device for a long time.

Next, another embodiment of the present invention will be described with reference to FIG. In the X-ray CT apparatus shown in FIG.
Although the center axis of the rotatable pipe joint 10 is made to coincide with the rotation center axis C of the rotating part frame 2, in the X-ray CT apparatus shown in FIG. 2, the X-ray tube 3 is cooled to the rotation radius position. A major feature is that a large-diameter rotatable pipe joint 17 having an oil passage is adopted.

That is, in the rotatable pipe joint 17, the rotary side annular trough 18 and the fixed side annular trough 19 which respectively form the cooling oil flow passages on the low temperature side and the high temperature side are liquid-tightly provided via the sealing material 13. , And is rotatably fitted. The rotating-side annular trough 18 is formed by concentrically forming an annular flow path 20a for circulating the low temperature side cooling oil and an annular flow path 20b for circulating the high temperature side cooling oil. The rotating side annular trough 18 is supported by a bracket (not shown) protruding from the rotating portion frame 2. On the other hand, the fixed-side annular trough 19 similarly has a flow passage 21 for circulating the cooling oil on the low temperature side and the cooling oil on the high temperature side, respectively.
a and 21b are formed concentrically. The fixed-side annular trough 19 is fixed to the fixed frame 22. The rotating part frame 2 a is rotatably supported by the fixed frame 22 via a bearing 23. A pulley 24 is integrally fixed to an end portion of the rotating portion frame 2a, and the rotating portion frame 2a is configured to rotate in a predetermined direction by suspending a driving belt or the like on the pulley 24.

Also in the X-ray CT apparatus according to this embodiment,
Similar to the embodiment shown in FIG. 1, even if the rotating part frame 2a rotates, the cooling oil is supplied to the X-ray tube 3 through the rotatable pipe joint 17.
Therefore, the X-ray tube 3 can be efficiently cooled. Further, since the cooling unit 6a is not mounted on the rotating unit frame 2a, the rotating unit becomes light in weight and high-speed scanning becomes possible.

Particularly, in this embodiment, since the rotatable pipe joint 17 has a diameter larger than the diameter of the rotating portion frame 2a, it has the following advantages as compared with the X-ray CT apparatus shown in FIG. That is, in the X-ray CT apparatus shown in FIG. 1, since the rotatable pipe joint is arranged near the center of rotation of the rotating frame 2, one end of the X-ray exposure area is closed. Therefore, the subject (subject) 7
There is a possibility that the stroke (stroke length) of the top of the bed on which the subject 7 is placed is limited to a narrow range while giving a feeling of pressure to the subject.

However, in the X-ray CT apparatus shown in FIG. 2, since the hollow and large-diameter rotatable pipe joint 17 is used, the end of the X-ray exposure region is kept open.
Therefore, there is an advantage that the subject 7 is not given a feeling of pressure, the stroke length of the bed top can be lengthened, and an arbitrary part of the subject can be a scan target.

In each of the above embodiments, the X-ray CT apparatus has been described as an example, but the present invention is not limited to the above-mentioned embodiments, and has a mechanism for carrying out a rotating operation by mounting an X-ray tube. It can be applied to all X-ray apparatuses. For example, the present invention can be applied to an X-ray fluoroscopic diagnosis apparatus in which an X-ray tube is integrally mounted on a drive arm, an X-ray angiography apparatus (X-ray angiography apparatus), and the like.

[0026]

As described above, according to the X-ray CT apparatus of the present invention, since the cooler is arranged on the fixed portion of the apparatus body without being fixed to the rotary frame, the weight of the rotary frame as a whole is reduced. It is reduced, and the structure of the rotating part is made compact. Therefore, the rotating operation of the rotating unit is facilitated and high-speed scanning becomes possible.

Further, by disposing the cooler in the fixed portion outside the apparatus main body casing, the cooler can be increased in size without being restricted by the weight limit of the rotating portion, and the cool air outside the main body of the apparatus can be used as intake air of the cooler. Since it can be used, the cooling efficiency of the X-ray tube can be significantly increased. Furthermore, since high-temperature exhaust heat from the cooler is released to the outside of the device body casing, the temperature rise and temperature change inside the device body are reduced,
Regardless of the frequency of scanning, the temperature inside the apparatus main body is stable, a high-quality diagnostic image can be obtained, and the operational reliability of the apparatus can be greatly improved.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of an X-ray CT apparatus according to the present invention.

FIG. 2 is a side sectional view showing another embodiment of the X-ray CT apparatus according to the present invention.

FIG. 3 is a front view schematically illustrating the configuration of a conventional X-ray CT apparatus.

[Explanation of symbols]

 1 Device body casing 2, 2a Rotating part frame 3 X-ray tube 4 Detector 5, 5a, 5b Cooling pipe 6, 6a Cooler (oil cooler) 7 Subject (examinee) 8 Cooling fin 9 Cooling fan 10 Freely rotatable Pipe joint 11 Rotation side trough 12 Fixed side trough 13 Sealing material 14a, 14b Flow passages 15a, 15b Flow passage 16 Circulation pump 17 Rotatable pipe joint 18 Rotation side annular trough 19 Fixed side annular trough 20a, 20b Flow passages 21a, 21b Flow path 22 Fixed part frame 23 Bearing 24 Pulley C Rotation center axis

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideki Fujimoto 1385-1 Shimoishigami, Otawara-shi, Tochigi Stock company Toshiba Nasu factory

Claims (2)

[Claims] 1. A rotary unit frame rotatably arranged in a casing of an apparatus body, an X-ray tube integrally mounted on the rotary unit frame, and a cooling medium for transferring a refrigerant medium to an X-axis.
X-ray C provided with a cooler for feeding and discharging the X-ray tube to cool the X-ray tube
In the T-apparatus, the X-ray CT apparatus is characterized in that the cooler is arranged in a fixed portion of the apparatus main body, and a rotatable pipe joint is interposed in a cooling pipe connecting the X-ray tube and the cooler. 2. The X-ray CT apparatus according to claim 1, wherein the cooler is arranged in a fixed portion outside the apparatus main body casing.