JPH0586218B2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to a multi-orbit X-ray tomography apparatus.

[Technical background of the invention]

In general, an X-ray tomography device moves an X-ray tube along a certain trajectory in order to obtain a tomographic image of the inside of a subject, and while maintaining a certain relationship with the X-ray tube, a fixed point on the X-ray film is set at a certain point. The X-ray film is moved along a trajectory so that the relative speed between the projection of an arbitrary point on a plane of the subject onto the X-ray film surface and the X-ray film is zero.

Among such X-ray tomography devices, multi-orbit X
In the case of a linear tomography apparatus, the X-ray tube is generally moved in a plane parallel to a plane containing the subject's body axis so as to draw a trajectory such as a straight line, circle, or spiral.

A conventional example of such a device will be explained with reference to FIGS. 4 and 5.

This device has a rotary motion mechanism 2 that provides a circular trajectory for the X-ray tube 1, a linear motion mechanism 3 that provides a linear trajectory for the X-ray tube 1, and separate mechanisms for the rotational motion mechanism 2 and the linear motion mechanism 3. The driving force generating mechanism 6 includes first and second driving force generating sections 4 and 5 that transmit driving force.

The rotational movement mechanism 2, as shown in FIG.
A first bearing 7 is provided in the center, and the central shaft body 8 is rotatably held by the bearing 7. An upper disk 9 whose outer periphery is formed into a pulley shape and a cylindrical shape integral with the upper disk 9 are provided. It consists of a lower disk 10 fixed to a portion 9a, and the upper disk 9 and the central shaft body 8 are connected and released within a hollow portion 9b formed between the upper disk 9 and the lower disk 10. It is composed of a rotating body 12 equipped with a brake 11.

The linear motion mechanism 3 includes a first pulley 13 fixed to the central shaft body 8 projecting upward from the center of the rotating body 12, a first sprocket 14 fixed to the central shaft body 8 within the hollow portion 9b, and the first sprocket 14 fixed to the central shaft body 8 within the hollow portion 9b. An internal shaft body 15 that is rotatably supported by a second bearing 15a attached to the lower disk 10 within the hollow portion 9b, and a second sprocket 16 that is fixed to the internal shaft body 15 within the hollow portion 9b.
, the first sprocket 14, the second sprocket 1
An internal chain 17 stretched between 6 and a lower disc 1
A third sprocket 18 fixed to an internal shaft body 15 protruding downward from the cylindrical portion 9a, and a first external bearing 19a and a second external bearing 19b symmetrically attached to the lower disk 10 further outward from the cylindrical portion 9a. The first external shaft body 20a and the second external shaft body 20b are respectively pivotally supported by
8. an external chain 22 stretched between the fourth sprocket 21;
6th sprockets 23a, 23b, 5th and 6th sprockets
It has a linear drive chain 24 stretched between sprockets 23a and 23b.

As shown in FIG. 1, the X-ray tube 1 is attached to a rotating body 12 via an X-ray tube holder 25, and is linked to a linear motion mechanism 2 and a rotary motion mechanism 3.

That is, the X-ray tube holding section 25 has a U-shaped shaft support 26 rotatably attached to the rotating body 12, and one end is held by the shaft support 26 and the other end is attached to the rotating body 12. a first cylindrical body 27 facing in a direction intersecting the chain 24; and a holding member 28 that is slidably fitted onto the outer periphery of the first cylindrical body 27 and holds the X-ray tube 1 at its tip. The second prepared
a cylindrical body 29; and a third cylindrical body 31 that projects vertically upward from the second cylindrical body 29 and rotatably relative to the second cylindrical body 29, and has a rectangular connecting plate 30 attached to its upper end. By connecting the connecting plate 30 and the chain 24, the second cylindrical body 29 slides against the first cylindrical body 27 which rotates about the shaft support 26 as the chain 24 rotates. As the third cylindrical body 31 moves, the third cylindrical body 31 rotates to apply a linear motion to the X-ray tube 1 in the direction of the arrow X shown in FIG.

The first driving force generating mechanism 4 of the power generating mechanism 6
A first motor 35, a first driving pulley 36 attached to the driving shaft 35a of the first motor 35,
There is a tension between the first driven pulley 38a and the second driven pulley 38b, to which the driving force is transmitted from the first driving pulley 36 via the first strip 37, and the second driven pulley 38b and the upper disc 9. Article 2 established 39
and gives rotational motion to the rotating body 12.

Further, the second driving force generating mechanism 5 includes a second motor 40, a second driving pulley 41 attached to the driving shaft 40a of the second motor 40, and an area between the second driving pulley 41 and the first pulley 13. It has a stretched third strip body 42 and drives the linear motion mechanism 3.

In the conventional device having the above configuration, the first pulley 13 is driven by the second driving force generating mechanism 5 with the brake 11 turned off, and thereby the first sprocket 14 → internal chain 17 → second sprocket 16
→Third sprocket 18 → external chain 22 → fourth sprocket 21 in the order of which the driving force is transmitted to rotate the chain 24 stretched between the fifth and sixth sprockets 23a and 23b to create a straight trajectory in the X-ray tube 1. I'm trying to get them to draw it.

Further, with the brake 11 turned off and the second driving force generating mechanism 5 stopped, the rotating body 12 is driven by the first power generating mechanism 4, thereby causing the X-ray tube 1 to draw a circular orbit. That's what I do.

Further, while appropriately setting the rotation speeds of the first motor 35 and the second motor 40, the rotating body 12 and the linear motion mechanism 3 are simultaneously driven by the first and second power generation mechanisms 4 and 5, and the X-ray tube 1 A spiral trajectory is given to the

[Problems with background technology]

The conventional device with the above configuration has the following problems.

First, when giving the X-ray tube 1 a circular orbit or a straight orbit, either one of the first and second power generating mechanisms 4 and 5 will be stopped, which is mechanically wasteful. .

Second, when generating a spiral trajectory, it is necessary to accurately match the rotation ratio and phase of both the first and second motors 35 and 40, but it is not difficult to control the two motors simultaneously in this way. Incurring an increase in circuit costs.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a multi-orbit X-ray tomography apparatus that can generate linear, circular, and spiral trajectories using a driving force generation mechanism using one motor. It is something to do.

[Summary of the invention]

Summary of the present invention for achieving the above object includes a rotating body rotatably supported, an X-ray tube attached to the rotating body so as to hold an A wire tube holding part;
a linear motion mechanism that is attached to the rotating body and gives linear motion to the X-ray tube, and drives the rotating body and the linear motion mechanism separately or simultaneously to
In a multi-orbit tomography apparatus in which a wire tube draws a circular orbit, a linear orbit, or a spiral orbit, a driving force using one motor capable of individually transmitting driving force to the rotating body and the linear motion mechanism. A generating mechanism is provided, the rotating body and the linear motion mechanism are in a connected state or a released state to give the X-ray tube a circular orbit or a linear trajectory, and the rotating body and the linear motion mechanism are in a released state to cause the rotating body to move. This is characterized in that the X-ray tube is given a spiral trajectory by utilizing the relative motion between the two caused by driving.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to FIGS. 1 to 3.

In the apparatus of this embodiment, parts having the same functions as those of the conventional apparatus shown in FIGS. 4 and 5 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The device of this embodiment differs from the conventional device in that a single motor 61 is used as the driving force generating mechanism 60, and there is a restriction on connecting and releasing the central shaft body 8 from the fixed portion 80 of this device. The brake 81 is provided.

As shown in FIG. 3, the driving force generation mechanism 60 includes a driving pulley 62 attached to a driving shaft 61a of a motor 61, a first driven pulley 64 fixed to a first driven shaft 63, and a driving pulley 62 and a first driven pulley. Pulley 64
A second driven pulley 67 which is rotatably supported by the first driven shaft 63 and provided with a clutch 66, and which is rotatably supported by the first driven shaft 63 and a third driven pulley 69 provided with a clutch 68; a second driven shaft 70 disposed at a predetermined distance from the first driven shaft 63; and a fourth driven pulley 71 fixed to the upper part of the second driven shaft 70.
, a fifth driven pulley 72 also fixed to the lower part of the second driven shaft 70, a brake 73 for regulating the rotation of the second driven shaft 70, and the third driven pulley 6.
9, a connecting strip 74 stretched between the fifth driven pulley 72, the second strip 39 being connected to the fourth driven pulley 71, and the third strip 42 being connected to the second driven pulley 6.
7, respectively.

Next, the operation of the apparatus having the above configuration will be explained.

First, a case in which a straight trajectory is given to the X-ray tube 1 will be explained. Turn clutch 66 on, clutch 6
8, the brake 73 and the regulation brake 81 are both turned off, and the motor 61 is started with the brake 11 also turned off.

Then, the driving force from the motor 61 is transferred from the driving pulley 62 to the strip 65 to the first and second driven pulleys 64,
67 → third thread body 42 → first pulley 13 → first sprocket 14 → internal chain 17 → second sprocket 16 → third sprocket 18 → external chain 22 → via fourth sprocket 21 to fifth and sixth sprockets The signal is transmitted to 23a and 23b, and drives the chain 24 to rotate.

At this time, since the clutch 68 is off, the driving force of the motor 61 is not transmitted to the rotating body 12, and therefore the rotating body 12 remains stopped.

As the chain 24 rotates, the X-ray tube holding section 2
5 operates in the same manner as conventional devices and can provide the X-ray tube 1 with a straight trajectory.

Second, a case will be described in which the X-ray tube 1 is given a circular orbit.

In this case, the clutch 66 is turned off, the clutch 68 is turned on, the brake 73 and the regulating brake 8 are turned off.
1 off and brake 11 on.

Then, the driving force from the motor 61 is applied to the driving pulley 62 → the strip 65 → the first driven pulley 63, the third driven pulley 69 → the fifth and fourth driven pulleys 72, 71.
→It is transmitted to the rotating body 12 via the second strip body 39. At this time, since the clutch 66 is off,
The driving force by the motor 61 is not transmitted to the linear motion mechanism 2, and the X-ray tube 1 is maintained at a constant position.

Therefore, the rotating body 12 can give the X-ray tube 1 a circular orbit.

Thirdly, a case in which a spiral trajectory is given to the X-ray tube 1 will be explained.

In this case, as in the case of circular orbit generation, the clutch 66 is turned off, the clutch 68 is turned on, and the brake 73 is turned off. On the other hand, regulation brake 8
1 is turned on and brake 11 is turned off. Then, the central shaft body 8 becomes unable to rotate.

At this time, the driving force by the motor 61 is transmitted to the rotating body 12 as in the case of circular orbit generation, but since the brake 11 is off, the first sprocket 1
4 is not affected by the rotational force of the rotating body 12.

Therefore, the linear motion mechanism 3 rotates together with the rotating body 12 without any driving force being transmitted from the motor 61 to the linear motion mechanism 3.

As a result, relative motion occurs between the rotating body 12 and the X-ray tube 1 connected to the linear motion mechanism 2 due to the difference in angular velocity, and the X-ray tube 1 moves in a spiral shape as the rotating body 11 rotates. It gradually moves toward the center of the rotating body 12 while drawing a trajectory of .

The present invention is not limited to the above embodiments,
It goes without saying that various modifications are possible within the scope of the gist.

〔Effect of the invention〕

According to the present invention described in detail above, linear, circular, and spiral trajectories can be generated in the X-ray tube by a driving force generation mechanism using one motor, simplifying the mechanism and facilitating control. Thus, it is possible to provide a multi-orbit X-ray tomography apparatus that can reduce the cost of the entire apparatus and also improve the accuracy when generating spiral trajectories.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing a device according to an embodiment of the present invention, FIG. 2 is a schematic plan view of the same device, FIG. 3 is a schematic sectional view of the same device, and FIG. 4 is a schematic perspective view of a conventional device. FIG. 5 is a schematic cross-sectional view of the device shown in FIG. 4. DESCRIPTION OF SYMBOLS 1... X-ray tube, 2... Rotating motion mechanism, 3... Linear motion mechanism, 12... Rotating body, 25... X-ray tube holding part, 60... Driving force generation mechanism, 61... Motor.

Claims (1)

[Claims] 1. A rotating body that is rotatably supported, an X-ray tube holder that holds an X-ray tube and is attached to the rotating body so that its relative position with respect to the rotating body can be varied, and and a linear motion mechanism that gives linear motion to the X-ray tube, and drives the rotating body and the linear motion mechanism separately or simultaneously to cause the X-ray tube to draw a circular trajectory, a linear trajectory, or a spiral trajectory. In the multi-orbital tomography device,
comprising a driving force generation mechanism using one motor capable of individually transmitting driving force to the rotating body and the linear motion mechanism, the rotating body and the linear motion mechanism being connected;
Alternatively, the rotating body and the linear motion mechanism are set in the released state to give the X-ray tube a circular orbit or a linear trajectory, and the rotating body is driven in the released state, using the relative motion between the two. A multi-orbit X-ray tomography device characterized by providing a spiral trajectory.