JPH0956710A - X-ray computer tomography apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray computer tomograohy apparatus capable of rotating a rotating frame at a high speed, to a frame support and realizing a high speed scanning. SOLUTION: A rotating frame is supported to be freely rotatable to a frame support. On the frame rotating unit, various kinds of units 200 -204 , namely an X-ray tube irradiating a subject disposed on a top board with X-ray beam of sector form and detector arrays detecting X-ray transmitted through the subject on multichannel comprising plural detectors radially arranged surrounding a force of the X-ray tube as the enter. The rotating frame has a cylindrical supporting part 10 which installs each of units 200 -204 in the inside wall part. By using the structure, the rotating frame rotates at a high speed and each unit can firmly maintain the firmly fixed to the supporting part even if a strong centrifugal force is applied to the units by high speed rotation of the rotating frame.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray computed tomography apparatus, and more particularly to an X-ray computed tomography apparatus having a gantry rotating unit rotatably provided with respect to a gantry fixed unit.

[0002]

2. Description of the Related Art Conventionally, a gantry of an X-ray computed tomography apparatus of this type (hereinafter sometimes abbreviated as an X-ray CT apparatus) has a fixed part and a rotating part, and the gantry rotating part is fixed to the gantry. It is provided so as to be rotatable with respect to the section. Then, as shown in FIG. 12, the gantry rotating part has a disc-shaped supporting member 30 having a hole, and on the surface of the disc-shaped supporting member 30,
For example, an X-ray tube 200 that radiates X-rays, and a detector 202 that detects transmitted X-rays that have been radiated from the X-ray tube and transmitted through the subject.
In addition, booster circuits, counter weights 201, 203, etc.
, 204 are provided. These devices 200
.About.204 (various devices provided in the gantry rotating unit will be referred to as a unit 20 hereinafter) rotate together with the gantry rotating unit during photographing.

Further, the unit 20 provided on the gantry rotating section and various devices (for example, an image reconstructing apparatus) provided on the gantry fixing section are electrically connected by a slip ring device, and the gantry rotating section is connected to the gantry fixing section. In contrast, it can be continuously rotated. Further, when the bed (top) on which the subject is placed is configured to be continuously moved in the body axis direction of the subject during continuous rotation of the gantry rotating unit, so-called helical scanning can be performed. it can. The helical scan enables high-speed acquisition of images of a wide area of the subject.

In recent years, in X-ray CT apparatuses, shortening the scan time is considered to be a major technical problem.
Therefore, if the gantry rotating unit is rotated at a high speed in order to shorten the scanning time, there is a problem that the acceleration in the centrifugal direction applied to the unit increases. More specifically, when the angular velocity and radius of the gantry rotating part are ω and r, respectively,
The acceleration α in the centrifugal direction of the gantry rotating part is given by the following expression (1), and the acceleration α increases as the angular velocity ω increases.

Α = rω ² (1) In this way, when the acceleration in the centrifugal direction increases due to the high-speed rotation of the gantry rotating part, as shown in FIG.
In a conventional X-ray CT apparatus having a configuration in which each unit 20 is arranged, each unit 20 is shaken in the centrifugal direction as indicated by a wavy line in the figure, and each unit 20 maintains a strong fixation to the disk-shaped member 30. There is a problem that you cannot do it. As a result, the operation of each unit 20 is affected to a considerable extent, which causes a problem that the quality of the captured image is deteriorated.

[0006] Generally, in an X-ray CT apparatus, as a measure against heat (mainly heat generation of an X-ray tube), a ceiling fan is attached to a mount fixing part to perform forced air cooling.
There is also a problem such as noise when the ceiling fan operates.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to address the above-mentioned circumstances, and its purpose is to achieve the following X.
A line computed tomography apparatus is provided. (1) An X-ray computed tomography apparatus capable of rotating the gantry rotating unit at a high speed with respect to the gantry stationary unit and realizing a high scanning speed. (2) An X-ray computed tomography apparatus having a simple structure that can be cooled with appropriate air circulation with low noise and does not require a ceiling fan.

[0008]

An X-ray computed tomography apparatus according to claim 1 of the present invention is provided so as to be rotatable with respect to a gantry fixed part, and has an gantry rotating part to which a unit is attached. In the tomography apparatus, the gantry rotating unit has a cylindrical supporting member, and the unit is attached to the inner wall of the supporting member.

An X-ray computed tomography apparatus according to a second aspect of the present invention is an X-ray computed tomography apparatus including a gantry rotating section rotatably provided with respect to a gantry fixed section. It is characterized in that it includes a blade member to be attached, and is provided with a blowing unit that blows air by rotating the blade member together with the gantry rotating part.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 11 is an external view of the X-ray CT apparatus according to the embodiment of the present invention. This embodiment includes a gantry 1, a bed 2, and a console 3. An opening 4 into which the subject is inserted is provided in the center of the gantry 1.
A bed 2 is arranged on the front of the gantry 1. The bed 2 is configured to be electrically adjustable in height. A top plate 5 on which the subject is placed is provided on the upper surface of the bed 2. The top plate 5 is configured to be able to slide electrically with respect to the fixed base 1. A keyboard 6 (which may include a mouse) and a CRT monitor 7 are arranged on the console 3, and a controller is housed in the console 3. This control unit is connected to both the gantry 1 and the bed 2 and controls the operations thereof.

The gantry 1 is composed of a gantry stationary part and a gantry rotating part, and the gantry rotating part is rotatably supported with respect to the gantry stationary part. The gantry rotating part has various units (200 to 204) described above, that is, an X-ray tube for irradiating a subject placed on the top plate 5 with a fan-shaped X-ray beam and a focus of the X-ray tube. A plurality of detectors are arranged in an arc shape centering on the center, and a detector array or the like for detecting the X-rays transmitted through the subject in multiple channels is provided.

More specifically, in the present embodiment,
As shown in FIG. 1A, the gantry rotating part has a cylindrical supporting member 10, and each unit (20) is provided on the inner wall of the supporting member.
0 to 204) is attached. still,
Each unit 20 is screwed in the centrifugal direction as shown in FIG. Further, each unit 20 is electrically connected to the gantry fixing portion via a slip ring device. The gantry fixing part is provided with a device for supplying electric power, a control signal or the like to each unit 20 of the gantry rotating part via a slip ring device.

With the above-described structure, each unit 20 can maintain a strong fixation to the support member 10 even when the gantry rotating unit rotates at a high speed and a great centrifugal force is applied thereto. Therefore, the gantry rotating part can be rotated at a higher speed with respect to the gantry fixed part, and the scan time is shortened (for example, the scan time is within 1 second).
To contribute.

Another example of the structure of the supporting member 10 having a cylindrical shape and mounting the unit on its inner wall is shown in FIG.
4 is a frame-shaped support member 11 in which pipe-shaped members are combined, or a cylindrical support member 12 having a bottom surface as shown in FIGS. 3A and 3B, or FIG.
There is a supporting member 13 as shown in FIGS. 5A and 5B, or a supporting member 14 as shown in FIG.

By the way, when the unit is attached to the cylindrical support member as described above, the X-ray CT apparatus according to the present embodiment operates and heat generated by driving each unit is generated inside the cylinder. It becomes muddy and cannot be cooled by the ceiling fan provided in the conventional frame fixing part. Therefore, in the present embodiment, FIG.
As shown in (b), the support member 10 has a plurality of blade members 40.
.. 40n are arranged, and the blade members 40 are rotated together with the gantry rotating unit to blow air to radiate heat inside the cylinder. As a result, the cooling can be performed without providing the ceiling fan, and the noise due to the ceiling fan is removed. Even when the support member for mounting the unit is not the cylindrical shape but the disk-shaped support member 30, the blade members 500, 501, ... 50n are arranged as shown in FIGS. 7 (a) and 7 (b). By arranging and blowing air, it becomes possible to cool without using the ceiling fan.

The direction of blowing air is arbitrary depending on the direction of the blade member and the rotating direction of the gantry rotating part. For example, as shown in FIG. 8, it may be a white arrow direction or a black arrow direction. Regarding the intake of the outside air (or the discharge of the blown air), for example, as shown in FIG. 9, a duct 70 is provided so that the outside air is sucked in (or discharged) from a desired direction.

The air flow rate may be controlled according to the rotation speed of the gantry rotating part. FIG.
FIG. 6 is a block diagram showing an example of control of an air flow rate according to a rotation speed of a gantry rotating unit. The rotation speed of the motor 62 that rotationally drives the rotation part of the gantry is controlled by the gantry rotation control 60,
The rotation speed information at that time is supplied to the air volume control 64, and the air volume control 64 controls the blade member 66 configured such that the angle, size, and number of sheets can be controlled. With this configuration, more appropriate air volume control can be performed. It should be noted that the present invention is not limited to the above-described embodiments, and can be implemented with various modifications.

[0018]

As described above, according to the present invention, the following X-ray computed tomography apparatus can be provided. (1) An X-ray computed tomography apparatus capable of rotating the gantry rotating unit at a high speed with respect to the gantry stationary unit and realizing a high scanning speed. (2) An X-ray computed tomography apparatus having a simple structure that can be cooled with appropriate air circulation with low noise and does not require a ceiling fan.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a gantry rotating unit of an X-ray CT apparatus according to an embodiment of the present invention.

FIG. 2 is a view showing another example (1) of the cylindrical support member according to the above embodiment.

FIG. 3 is a view showing another example (2) of the cylindrical support member according to the above embodiment.

FIG. 4 is a view showing another example (3) of the cylindrical support member according to the above embodiment.

FIG. 5 is a view showing another example (4) of the cylindrical support member according to the above embodiment.

FIG. 6 is a view showing a structure in which a blade member for blowing air is attached to a cylindrical support member according to the above embodiment.

FIG. 7 is a view showing a structure in which a blade member for blowing air is attached to the disk-shaped support member according to the above embodiment.

FIG. 8 is a diagram showing an example of a direction of air blowing in the embodiment.

FIG. 9 is a diagram showing a structure for inhaling outside air (exhausting air blowing) in the embodiment.

FIG. 10 is a block diagram showing an example of controlling the air flow rate according to the rotation speed of the gantry rotating unit according to the above embodiment.

FIG. 11 is a perspective view showing the outer appearance of the embodiment.

FIG. 12 is a diagram showing a configuration of a conventional gantry rotating unit.

[Explanation of symbols]

10 ... Cylindrical support member, 20 ... Unit, 40 ... Blade member.

Claims (3)

[Claims] 1. An X provided with a gantry rotating part, which is rotatably provided with respect to a gantry stationary part and to which a unit is attached.
In the X-ray computed tomography apparatus, the gantry rotating section has a cylindrical support member, and the unit is attached to an inner wall of the support member. 2. An X-ray computed tomography apparatus comprising a gantry rotating part rotatably provided with respect to a gantry fixing part, comprising a blade member attached to said gantry rotating part, and said wing member together with said gantry rotating part. An X-ray computed tomography apparatus comprising: a blowing unit that blows air by rotating. 3. The X-ray computed tomography apparatus according to claim 2, further comprising control means for controlling the flow rate of air blown by the blowing means according to the rotation speed of the gantry rotating part. .