JPH0450026B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for vertically moving and horizontally driving a rotary chair for a linearly accelerated irradiation device, which allows radiation therapy to be performed while a patient is in a comfortable sitting position.

In recent years, for example, patients with tumors or arteriovenous malformations (hereinafter, in this specification, the affected area to be treated with radiation will simply be referred to as the affected area) are not treated with surgery, but with ionization such as x-axis and gamma rays. Progress has been made in the treatment of chemically altering the cell tissue of the affected area by irradiating it with radiation (hereinafter, all ionizing radiation used for treatment is simply referred to as radiation).

[Conventional technology]

For example, treatment for brain tumors was performed by locating the tumor using a CT scan while the patient was lying on a bed, and then irradiating the affected area with radiation. Since radiation also destroys cell tissue in areas other than the affected area, the linearly accelerated irradiation device was moved in a fan-shape in a straight line to reduce the impact of the radiation dose on cells outside the affected area. Then, the radiation from the linearly accelerated irradiation device is applied to the patient's affected area once every day.
The treatment used was to chemically alter the cell tissue in the affected area by irradiating the area for 2 to 2 minutes and repeating this for several weeks.

If the center position of the affected area does not coincide with the rotation center of the linearly accelerated irradiation device, the radiation irradiation area will be inaccurate, which may cause damage to tissues other than the affected area.

Therefore, even the slightest deviation is not allowed between the position of the affected area when scanned by CT and the position of radiation irradiated by the linear acceleration irradiation device after lying in bed.

An example of a rotary chair for performing such treatment will be described with reference to FIG. 3, as proposed by the present applicant.

In FIG. 3, a rotating chair base 32 with a horizontal surface is placed on a floor 31. The housing 33 on the rotating chair base 32 is moved by the housing movement screw 4 with the help of x-axis flat rollers 49 and y-axis flat rollers 50.
After the positioning is performed in step 5, the housing is fixed to the rotary chair base 32 with housing fixing screws 51.

The housing 33 has a cylindrical main shaft 3
4 is rotatably supported via cross roller bearings and radial bearings. Moreover, inside the housing 33,
A motor 35 is attached to rotate the cylindrical main shaft 34. The motor 35 is
For example, the rotational speed of the cylindrical main shaft 34 is controlled to be constant using a flat servo motor by a control circuit (not shown) and the rotational speed detected from an encoder 36 into which the shaft of the cylindrical main shaft 34 is inserted.

The rotation of rotor 37 in motor 35 is also transmitted to cylindrical main shaft 34 .

In the lower center of the cylindrical main shaft 34,
One end of the vertically movable screw 38 is fixed.

Further, a screw is cut on the circumferential surface of the vertically movable screw 38, and the cylindrical telescopic shaft 4 is connected to the screw and the ball screw nut 39.
0 is rotatably attached.

A pedestal body attachment fringe 41 is provided at the upper end of the cylindrical telescopic shaft 40, and a pedestal body 42 is placed thereon. A seat portion 43 is attached to the base body 42 so as to be slidable and replaceable in the left-right direction.

A clutch 44 is attached to the upper end of the cylindrical main shaft 34 so as to be slidable in the vertical direction. When the clutch 44 is to be slid upward, a clutch lever 47 is attached to the side support 46 of the seat main body 42 having an armrest 45'.
Pull it up as shown in Figure 3. Kuratsuchi・
When the lever 47 is pulled upward, the wire connected to the clutch lever 47 pulls the clutch 44 upward against the spring force.

As a result of this action, the clutch concave portion provided on the clutch 44 disengages from the clutch convex portion provided on the cylindrical main shaft 34, and the rotation of the cylindrical main shaft 34 is caused by the rotation of the cylindrical telescopic shaft 40. It will no longer be transmitted.

Therefore, the rotation of the cylindrical main shaft 34 is controlled by the vertically moving screw 38 and the ball screw.
It is transmitted via the nut 39 to the cylindrical telescopic shaft 40 . At this time, the cylindrical telescopic shaft 40 rises without rotating.

When the clutch lever 47 is pulled down, the cylindrical main shaft 34 and the cylindrical telescopic shaft 4 are moved by the engagement between the clutch concave portion and the clutch convex portion.
0, and the rotation of the motor 35 causes the rotary chair to rotate horizontally.

Note that the rotary chair for the linearly accelerated irradiation apparatus can be transported to a predetermined location by inserting a suspension support rod of a moving trolley (not shown) into the suspension support hole 48.

During treatment, in order to irradiate radiation to the center of the affected area, the patient's affected area is aligned with the rotating axis of the rotating chair.
Further, the rotation axis of the rotary chair is made to coincide with the rotation center of the linear acceleration irradiation device (not shown).

The patient sits on a rotating chair and is rotated about the center of the affected area in a horizontal plane at a constant angular velocity of, for example, 1/2 revolution per second. A linearly accelerated irradiation device (not shown) is used, for example, in a vertical plane at the center of the affected area.
Radiation is irradiated to the center of the affected area for several minutes to several tens of minutes while rotating within a 90-degree range. The affected area is treated by repeating this process for several days to several weeks to destroy the cell tissue in the affected area.

[Problem to be solved by the invention]

Even if the bed is moved in a pendulum-like manner in a horizontal plane around the patient's lesion, rotating the bed around the patient's lesion not only requires a large amount of space but also poses problems in the accuracy of rotation. Ta. If the rotation of the bed and linear acceleration irradiation device is incorrect, the radiation will be concentrated in a large oval position centered on the affected area, which may damage normal tissue around the affected area. .

In addition, after deciding where to sleep in bed, you will need to use a CT scan to determine the center position of the affected area, and then return to the bed to undergo long-term radiation therapy.
Too much effort for the patient.

Furthermore, the rotation of the servo motor is designed to control the rotary chair at about 1/2 rotation per second, but the rotation of the servo motor also needs to move the seat itself up and down. If one servo motor is used to rotate the swivel chair and move the seat body up and down in this way, there will be a large difference in the load.
The rotation was accompanied by vibration.

The present invention is intended to solve the above-mentioned problems, and is designed for use in a linearly accelerated irradiation device that not only can improve rotation accuracy without taking up much space, but also does not cause damage to normal tissue other than the affected area. The purpose of the present invention is to provide a device for vertically moving and horizontally driving a rotating chair.

Another object of the present invention is to provide a vertical movement and horizontal drive device for a rotary chair for a linearly accelerated irradiation device that can maintain a natural sitting posture so as to reduce patient pain during treatment time.

Furthermore, it is an object of the present invention to provide a vertical and horizontal drive device for a rotary chair for a linearly accelerated irradiation device that stably rotates not only when rotating the rotary chair horizontally but also when vertically moving.

[Means to solve the problem]

In order to achieve the above object, the vertical drive device for a rotary chair for a linearly accelerated irradiation device according to the present invention includes a cylindrical main shaft attached to the rotor of a servo motor that horizontally rotates the rotary chair;
It rotates together with the cylindrical main shaft, and slides in the vertical direction via a vertically movable ball screw provided inside the cylindrical main shaft and a vertically movable ball screw nut rotatably connected to the vertically movable ball screw. a cylindrical telescopic shaft that is movable and rotates horizontally together with the cylindrical main shaft, and is provided between the cylindrical main shaft and the vertically movable ball screw; and one end is fixed to the vertically movable ball screw nut. a cylindrical rotation transmission shaft, the other end of which is connected to the rotating shaft of the seat main body, and which is provided between the vertical motion ball screw and the cylindrical telescopic shaft, and a seat main body mounting flange that is connected to the cylindrical telescopic shaft. a geared motor that is attached to the lower part of the seat body and moves the seat body up and down; and a transmission means that transmits the rotation of the geared motor to a cylindrical rotation transmission shaft. It consists of

Further, the transmission means is constituted by a bevel gear spirally connected to the output shaft of the geared motor.

Further, the cylindrical telescopic shaft rotates together with the cylindrical main shaft by a keyed flange attached to the cylindrical main shaft, and is driven in the vertical direction by a keyway escaping the keyed flange. It is composed of

Further, at the lower part of the pedestal body, there is a lower limit sensor that detects the lower limit position of the pedestal body by contacting the pressing plate attached to the cylindrical main shaft, and a reflection angle from the pressing plate. and an upper limit sensor that detects the upper limit position of the seat body.

Furthermore, the rotating chair is configured to be freely driven in the horizontal direction with the aid of x- and y-axis flat rollers.

[Effect]

A case where the base body is horizontally rotated will be explained.

First, rotation of the servo motor causes a cylindrical main shaft attached to the rotor of the servo motor to rotate. Rotation of the cylindrical main shaft is transmitted to the cylindrical telescoping shaft by means of a keyed flange. The rotation of the cylindrical telescopic shaft is transmitted to the seat main body via the seat main body mounting flange.

A rotating chair is attached to the main body of the seat,
The rotating chair rotates horizontally at a constant angular velocity necessary for medical treatment under the control of servo motors.

Next, an explanation will be given of the operation for raising the seat body to which the rotary chair is attached to a height suitable for medical treatment.

When the geared motor rotates, this rotation is transmitted from the output shaft of the geared motor to the cylindrical rotation transmission shaft via the transmission means. The rotation of the cylindrical rotation transmission shaft is transmitted to a vertically movable ball screw/nut coupled to the cylindrical rotation transmission shaft. The vertical ball screw/nut rotates by moving the vertical ball screw/nut in the vertical direction by the screw of the vertical ball screw. Vertical movement The vertical movement of the ball screw/nut moves the cylindrical telescopic shaft in the vertical direction.

The pedestal body is attached to the upper end of the cylindrical telescoping shaft via the pedestal body mounting flange, so the vertical movement of the cylindrical telescoping shaft also moves the rotating chair attached to the pedestal body in the vertical direction. do.

Further, the transmission means for transmitting the rotation of the geared motor to the cylindrical rotation transmission shaft is configured to transmit the rotation of the geared motor to the cylindrical rotation transmission shaft.
By using a spiral bevel gear, the rotational force of a geared motor can be smoothly transmitted from the output shaft of the motor.

Further, the cylindrical telescopic shaft rotates together with the cylindrical main shaft by means of a keyed flange attached to the cylindrical main shaft, and when moving in the vertical direction, a key escapes from the keyed flange. A groove is provided.

Further, a lower limit sensor is provided at the lower part of the seat body to detect the lower limit position of the seat body by contacting a pressing plate attached to the cylindrical main shaft. Since it is not possible to use a mechanical switch to reach the upper limit position due to the rise of the base body, the light emitted from the optical sensor is applied to the press plate, and the time when the reflected light from there reaches a specified angle is determined. Detected as the upper limit position.

Furthermore, between the rotating chair and the rotating chair base,
Because of the intervening x- and y-axis flat rollers, the swivel chair can move freely in the horizontal direction either manually or by motor drive.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is an explanatory diagram of a vertical drive device for a rotary chair for a linear acceleration irradiation device, and FIG. 2 is a plan view of FIG. 1.

A rotary chair base 1 is placed horizontally on a floor 31 (not shown). On the rotating chair base 1 are flat rollers 4 in the x-axis and y-axis directions.
9 and 50 slidably fasten the housing 2 of the swivel chair. The housing 2 is fixed by positioning it with the housing moving screw 45, and by fixing the housing 2 with the housing fixing screw 51.
Fixed to.

Crossed roller bearing 3 in housing 2
A cylindrical main shaft 5 is rotatably attached to the radial bearing 4.

The cylindrical main shaft 5 is fixed to the housing 2 via a cross-roller bearing 3, and is equipped with, for example, a flat servo shaft.
It is fixed to the rotor 7 of the motor 6. Further, a vertically movable ball screw 8 is fixed to the center of the cylindrical main shaft 5, and a screw is cut around the vertically movable ball screw 8. Further, a cylindrical telescopic shaft 9 and a cylindrical rotation transmission shaft 10 are inserted between the cylindrical main shaft 5 and the vertically movable ball screw 8.

The cylindrical telescopic shaft 9 can be rotated together with the cylindrical main shaft 5 by means of a keyed flange 11 and can be moved upward by means of a keyway 12. The lower end of the cylindrical rotation transmission shaft 10 is fixed to a vertically moving ball screw nut 13,
Its upper end is attached to a rotating arm 14.

A geared motor 1 is installed at the bottom of the base body 15.
6 is attached, and its output shaft is connected to the first bevel gear assembly 17. The first bevel gear assembly 17 is, for example, as shown in FIG.
It is connected to a central bevel gear assembly 19 via a bevel gear assembly 18 . And, for example, the first
and the second bevel gear assembly 17, 18 is 1:1,
The central bevel gear assembly 19 has a gear ratio of 1:3.

A gear box 23 is located at the bottom of the base body 15.
A pedestal main body mounting flange 24 is attached via. The rotating arm 14 is rotatably attached to the base body mounting flange 24 via a cross roller bearing 25. The upper end of the rotating arm 14 is fixed to the central bevel gear assembly 19, and the lower end is fixed to the cylindrical rotation transmission shaft 10, respectively.

A lower limit switch 26 for detecting the lower limit position of the seat body 15 is provided at the lower part of the seat body 15. This lower limit switch 2
6 comes into contact with the pressing plate 28 provided at the upper end of the keyed flange 11, so that the seat main body 1
Detect the lower limit position of 5. Further, since the upper limit sensor 27 (see FIG. 2) cannot be a mechanical switch, it is installed in the lower part of the seat body 15 as a switch composed of, for example, an emitting element and a light receiving element.

The operation of the vertical drive device for a rotary chair for a linearly accelerated irradiation device configured as above will be explained.

First, a case will be described in which the seat main body 15 is horizontally rotated.

The rotation of the servo motor 6 causes the cylindrical main shaft 5 attached to the rotor 7 of the servo motor 6 to rotate. The servo motor 6 is controlled based on the rotation speed detected by the encoder 36 so that it always has a desired rotation speed. Since there is a keyed flange 11 as shown in FIG. 1, the cylindrical telescopic shaft 9 rotates as the cylindrical main shaft 5 rotates. Cylindrical telescopic shaft 9
The rotation is transmitted to the seat main body 15 via the seat main body mounting flange 24 and the gear box 23.

A rotating chair (not shown) is attached to the seat main body 15. Therefore, the rotating chair rotates in the horizontal direction under the control of the servo motor 6 at a constant angular velocity necessary for medical treatment. The rotation speed is, for example, 1/2 rotation per second.

Next, a description will be given of an operation for raising the seat main body 15 to which the rotary chair is attached to a height suitable for medical treatment.

When rotating the geared motor 16, rotation from the output shaft of the geared motor 16 is transmitted from the first gear assembly 17 and the second bevel gear assembly 18 to the central bevel gear assembly 19. Depending on the ratio of bevel gears in the bevel gear assembly, geared
The rotational force of the motor 16 can be amplified. Further, by using a spiral bevel gear as the bevel gear of the bevel gear assembly, the rotation of the geared motor 16 can be smoothly transmitted. Central bevel gear assembly 1
The rotating arm 14 fixed to the gear 9 is connected to the cylindrical rotation transmission shaft 10.
The rotation of the motor 16 is transmitted to the cylindrical rotation transmission shaft 10.

The rotation of the cylindrical rotation transmission shaft 10 is transmitted to a vertically movable ball screw nut 13 coupled to the cylindrical rotation transmission shaft 10. Vertical ball screw/nut 1
3, the screw of the vertically movable ball screw 8 moves the vertically movable ball screw/nut 13 in the vertical direction. The vertical movement of the vertically movable ball screw/nut 13 moves the cylindrical telescopic shaft 9 in the vertical direction.

Since the seat main body 15 is attached to the upper end of the cylindrical telescopic shaft 9 via the seat main body attachment flange 24, the rotating chair is attached to the seat main body 15 by vertical movement of the cylindrical telescopic shaft 9. also moves up and down.

Further, the cylindrical telescoping shaft 9 is connected to the cylindrical main shaft 5 by means of a keyed flange 11 attached to the cylindrical main shaft 5.
The vertical movement of the cylindrical telescopic shaft 9 avoids the keyed flange 11 by the keyway 12.

Furthermore, a lower limit switch 26 is provided at the lower part of the seat main body 15 to detect the lower limit position of the seat main body 15 by contacting a press plate 28 attached to the keyed flange 11.

Since it is not possible to use a mechanical switch to reach the upper limit position due to the rise of the seat main body 15, the light emitted from the optical sensor is applied to the press plate 28, and the reflected light from there reaches a specified angle. The hour is detected as the upper limit position.

Furthermore, an x is provided between the rotating chair and the rotating chair base 1.
Axial and y-axis flat rollers 49,50 are interposed. The rotary chair is freely driven in the horizontal direction by screws 45 for moving the housing in the x-axis and y-axis directions or by a drive motor (not shown).

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments. Various design changes can be made without departing from the scope of the invention as set forth in the claims.

For example, the transmission mechanism such as the shape of the bevel gear in a bevel gear assembly, and the limit sensor,
It goes without saying that other known means may be used.

〔Effect of the invention〕

According to the present invention, since the horizontal rotation and vertical movement of the rotary chair are driven by separate motors, it is possible to eliminate abnormal vibrations caused by differences in load.

Further, according to the present invention, the four-layer structure of the cylindrical main shaft, the cylindrical telescoping shaft, the cylindrical rotation transmission shaft, and the vertically movable ball screw allows stable horizontal rotation of the swivel chair and It is now possible to move the main body up and down smoothly.

Furthermore, according to the present invention, a geared motor for moving the seat body and a transmission mechanism such as a bevel gear for transmitting rotation from the geared motor are provided at the bottom of the seat body, so the structure becomes compact. With,
The motor for moving the rotating chair up and down can be made smaller.

Further, according to the present invention, since the flat rollers in the x-axis and y-axis directions are interposed between the rotating chair and the rotating chair base, the rotating chair can be horizontally moved manually or by motor drive with a small amount of force. can be freely driven in any direction.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the vertical movement drive device of the rotary chair for the linear acceleration irradiation device, Fig. 2 is a plan view of the vertical movement drive device of the rotary chair for the linear acceleration irradiation device, and Fig. 3 is a diagram of the vertical movement drive device of the rotary chair for the linear acceleration irradiation device. It is a rotational drive explanatory diagram. 1... Rotating chair base, 2... Housing, 3...
...Cross roller bearing, 4...Radial bearing, 5...Cylindrical main shaft, 6...Servo motor, 7...Rotor, 8...
...Vertical ball screw, 9... Cylindrical telescopic shaft, 10... Cylindrical rotation transmission shaft, 11... Flange with key, 12... Keyway, 13... Vertical ball screw/nut, 14... Rotating arm, 15...
Base body, 16...Geared motor, 17...
First bevel gear assembly, 18...Second bevel gear assembly, 19...Central bevel gear assembly, 23...Gear box, 24...Seat body mounting flange, 2
6... Lower limit switch, 27... Upper limit sensor, 28... Pressing plate, 45...
Housing moving screw, 49...Flat roller in the x-axis direction, 50...Flat roller in the y-axis direction, 51...Housing fixing screw.

Claims (1)

[Scope of Claims] 1. A rotary chair for a linearly accelerated irradiation device for performing treatment by irradiating radiation to an affected area by aligning the center of rotation of the linearly accelerated irradiation device and the rotating chair with the center of the affected area, comprising: the rotating chair; A cylindrical main motor attached to the rotor 7 of a servo motor 6 horizontally rotates the
a shaft 5, rotating together with the cylindrical main shaft 5;
A vertically movable ball screw 8 provided inside the cylindrical main shaft 5, and a vertically movable ball screw nut 13 rotatably coupled to the vertically movable ball screw 8, are capable of sliding in the vertical direction, and are cylindrical. main shaft 5
A cylindrical telescopic shaft 9 is provided between the cylindrical main shaft 5 and the vertically movable ball screw 8, and one end is fixed to the vertically movable ball screw nut 13, and the other end is fixed to the vertically movable ball screw nut 13. A cylindrical rotation transmission shaft 10 connected to the rotation axis of the base body and provided between the vertically movable ball screw 8 and the cylindrical telescopic shaft 9; The pedestal body 15 attached
A geared motor 16 that is attached to the lower part of the base body 15 and moves the base body 15 up and down; Transmission means 17, 18 that transmits the rotation of the geared motor 16 to the cylindrical rotation transmission shaft 10. 1
9, 14, A vertical movement drive device for a rotary chair for a linearly accelerated irradiation device, characterized by comprising: 2 the transmission means is the geared motor 16;
2. The vertical movement drive device for a rotary chair for a linearly accelerated irradiation device according to claim 1, wherein a spiral bevel gear is used from the output shaft. 3 The cylindrical telescopic shaft 9 rotates together with the cylindrical main shaft 5 by means of a keyed flange 11 attached to the cylindrical main shaft 5, and is rotated in the vertical direction by means of a keyway 12 that escapes from the keyed flange 11. 2. The vertical movement drive device for a rotary chair for a linearly accelerated irradiation device according to claim 1, wherein the device is driven by: 4. A lower limit sensor 26 for detecting the lower limit position of the seat body 15 by contacting the pressure plate 28 attached to the cylindrical main shaft 5 is provided at the lower part of the seat body 15, and a lower limit sensor 26 for detecting the lower limit position of the seat body 15; 2. The vertical movement drive device for a rotary chair for a linearly accelerated irradiation apparatus according to claim 1, further comprising an upper limit sensor 27 for detecting the upper limit position of the seat main body 15 based on a reflection angle from the pedestal main body 15. 5. The horizontal drive device for a rotary chair for a linearly accelerated irradiation apparatus according to claim 1, wherein the rotary chair is freely driven in the horizontal direction with the help of x-axis and y-axis flat rollers.