JPS6266838A - X-ray tomographic apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an X-ray cross section 'ff4 for performing linear tomography, for example.
1I! This invention relates to improvements to lighting devices.

[Technical background of the invention 1 Generally, an X-ray tomography W4 imaging device moves an X-ray tube along a non-focal trajectory in order to obtain a tomographic image of the inside of a subject, and at the same time has a certain relationship with the machine. While maintaining
A fixed point on the film is moved along a certain trajectory, and any point on a plane within the subject is configured so that the relative velocity between the projection projected onto the film surface and the film becomes zero. . Among such X-ray tomography devices,
Straight fault II! In the case of am for shadows, Fig. 2(a) (
In the case of the linear movement type shown in b), the X-ray tube 1 having the X-ray diaphragm 1a is placed relative to the film 3 with the subject 2 in between, and the In the case of the circular movement type shown in Fig. 3, the movement moves along an arcuate trajectory within a plane (in the paper) that includes the body axis and the X-ray focal point. I try to move it.

In order to obtain such a trajectory, generally, as shown in FIG. 2(b), which is a side view of FIG.
This connecting column 63 is rotated about a shaft 7 by a drive mechanism (not shown).

Furthermore, in such an apparatus, as shown in FIGS. 2 and 3, when the X-ray tube 1 is in front of the subject 2, the direction E of the rotation axis of the rotating anode.

Generally, the X-ray tube 1 is installed so that E' is parallel to the body axis of the subject 2.

Regarding the XSI tube 1, there is a tendency to increase the rotation speed of the rotating anode in order to increase the heat capacity, and the current rotation speed is usually 3.60 rpm, but the high speed type Many rotate at 9,000 to 10.00 rpm.

FIG. 4 shows the cross-sectional configuration of the rotating anode X-ray tube. In FIG. 4, 8 is a case made of lead or the like that houses the X-ray tube body 9, 10 is a stator, 11 is a rotor, 12 is a shaft (rotation shaft) of rotor 11, 13 is an anode attached to shaft 12, 14 1 is a filament, and 15 is a support portion (bearing) of the rotor.

[Problem 1 in the background art: In the conventional X-ray tomography '#i1 imaging device for straight section Ff4 imaging, Xl! As the tube moved, the direction of the x-ray tube's rotating anode was changing. That is, the X-ray tube is A-+B-C
(A'→B'→C'), the direction of the rotating anode of the X-ray tube becomes D-+E-4F (D'→E'-JF")
It was changing.

As is well known, a rotating object has the property of trying to keep its axis of rotation in a fixed direction, and this property becomes stronger as the rotation speed of the rotating body increases, and the speed at which the direction of the rotation axis changes increases. It has a so-called gyro effect that increases speed.

Therefore, in this type of X-ray linear tomography apparatus, the direction of the rotating anode changes while the X-ray tube is moving, so that a gyroscopic force acts on the anode rotating shaft and its support (bearing, etc.).

Especially in recent years, the rotation speed of the anode has been increased to further increase the heat capacity, and the negative effects of movement (blur, etc.)
There is a tendency to move the X-ray tube faster in order to reduce stress and reduce psychological distress for the patient.

This also strengthens the gyro effect described above, so rJA
We had no choice but to make the pole's rotating shaft thicker and increase the strength of the rotating support. These are all due to larger X-ray tubes,
The Chongyang power booster is IB, and it is not a good thing.

In addition, other devices that do not perform tomography do not have a gyroscopic effect, so there is no need to reinforce them. Therefore, the Xls tube for general imaging and the Xm tube for tomography must be made separately. There wasn't.

On the other hand, since there are limits to these reinforcements, there are restrictions on increasing the rotation speed of the anode to increase the heat capacity, and increasing the moving speed of the ×II tube to perform fault Vfi shadowing in a short time. was.

[Object of the Invention] The present invention was developed in view of the above circumstances, and is capable of rotating I! ! ! It is an object of the present invention to provide an X-ray tomography apparatus that can increase the number of rotations of the pole and increase the moving speed of the Xm tube by -F.

[Summary of the Invention] In order to achieve the above object, the present invention provides an X-ray tube such that the anode rotation axis of the X-ray tube is oriented in a direction perpendicular to the direction in which the Xl1l tube moves during tomography. By arranging the wire tube, the direction of the axis of rotation of the rotating anode does not change during tomography.

Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 4(a) and 4(b), in which the same parts as in FIGS. 2 and 3 are denoted by the same reference numerals. Figure 4(a) is a front view, Figure 4(b)
) is a side view, and Fig. 4 (tl) and Fig. 2 (b)
, and only the main parts are shown. As shown in Fig. 4, within a plane that includes the body axis of the subject 1 and the
In an X-ray linear tomography apparatus in which an Xm tube 1 moves in It is located.

With this configuration, the X-ray tube 1 becomes A //→B ″→
C'', the direction of the anodic rotation axis does not change at all, and no force is generated due to the gyroscopic effect, so there is no need to reinforce the anode rotation axis or its support. Although only the method in which the X-ray tube 1 moves on an orbit has been described, it goes without saying that it can be carried out in exactly the same way for a method in which the X-ray tube 1 moves on an arcuate orbit.

It is known that when the X-ray tube 1 is arranged as in this embodiment, the X-ray distribution becomes non-trapezoidal due to the so-called tilt effect of X-ray generation. By correcting the distribution using a filter that roughly matches the shape and creating a flat X-ray distribution, an X-ray shadow image that does not cause clinical failure can be obtained, so there is almost no difference in RFP and images compared to conventional models. It is something.

[Effects of the Invention] As detailed above, according to the present invention, the X-ray tube is rotated so that the direction of the anode rotation axis of the XII tube is perpendicular to the direction in which the X-ray tube moves during the section BWa shadow. By arranging the X1a tube, the direction of the axis of rotation of the rotating anode does not change during the rupture, and no force due to the gyroscopic effect of the rotating anode is generated while the X1a tube is moving, so the rotation speed of the anode can be reduced. It is possible to increase the heat 'FIN' by increasing the X-ray tube, and it is possible to increase the moving speed of the X-ray tube to perform short-time transport. Ii layerlli! Shadow equipment can be provided.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the XVA tomography apparatus according to the present invention, FIGS. 2 and 3 are diagrams each showing a conventional example, and FIG. 4 is a sectional view of an X-ray tube. DESCRIPTION OF SYMBOLS 1... X-ray tube, 2... Subject, 3... X-ray film, 4... Holding arm, 5... Holding body, 6... Connecting column, 7... Shaft. Applicant's agent Patent attorney Takehiko Suzue (a) (b) β1
L (a) (b)Figure 2Figure 3Figure 4

Claims (1)

[Claims] Using a rotating anode X-ray tube, in order to obtain a targeted tomographic image inside an object, the X-ray tube focal point is moved along a certain trajectory, and at the same time, while maintaining a certain relationship with this, a certain point on the film is In an X-ray tomography apparatus configured such that the relative velocity between the projection projected onto the film plane and the film becomes zero at an arbitrary point on one plane within the subject by moving along a certain trajectory. An X-ray tomography apparatus, characterized in that the X-ray tube is arranged so that the direction of the anode rotation axis of the X-ray tube is perpendicular to the direction in which the X-ray tube moves during tomography.