JP2001238880A - X-ray equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide X-ray equipment which has a preventive measure against hitting a top plate and an image receptor each other. SOLUTION: Equipment is provided with a top plate that can move horizontally with an examinee lying on it, an image receptor that receives X-ray images of the examinee, and a system that adjusts the horizontal position of the image receptor for the top plate and posture of the image receptor in relation to the top plate. When the posture of the image receptor is not kept horizontal against the top plate, the X-ray equipment has a measure that movements of the top plate in certain directions are restricted, or changing posture of the image receptor can be limited, depending on the position of the top plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for projecting radiation such as X-rays on a subject to capture a radiation image.

[0002]

2. Description of the Related Art Radiation imaging apparatuses are used in the medical field, such as medical diagnosis of a subject, and in the inspection field, such as nondestructive inspection of substances. There are several types of image receivers that receive radiation images. Exists.

The first method is a radiographic method in which an intensifying screen and a radiographic film are used in close contact. This is because when the radiation transmitted through the subject is incident on the intensifying screen, the phosphor contained in the intensifying screen absorbs the energy of the radiation and generates fluorescent light, which causes the radiographic film to be exposed, Is recorded as a visible image.

[0004] The second type is known as an image recording / reproducing apparatus provided with a radiation detector made of a stimulable phosphor. When the radiation penetrates the subject and enters the stimulable phosphor, the stimulable phosphor stores part of the radiation energy.
When the stimulable phosphor is irradiated with visible light, the stimulable phosphor emits stimulated light according to the stored energy. That is, the stimulable phosphor accumulates radiation image information of the subject, the scanning means scans the stimulable phosphor with excitation light such as laser light, and the signal reading means photoelectrically reads the stimulated emission light, and Or a display means such as a CRT or the like records or displays as a visible image.

As a third method, there is known a radiation detector that detects radiation in real time and directly outputs the radiation, and the principle thereof is described in, for example, Japanese Patent Application Laid-Open No. Hei 8-116444. Digital detectors have been made possible by advances in semiconductor process technology. A scintillator and a solid-state photodetector are stacked, the scintillator converts radiation into visible light, and the solid-state photodetector photoelectrically converts the visible light. The solid-state photodetector has a configuration in which a solid-state photodetector made of a transparent conductive film and a conductive film is arranged in a matrix on a substrate made of quartz glass with an amorphous semiconductor film interposed therebetween. Since the radiation detector is a flat panel having a thickness of several mm, it is easy to reduce the thickness and weight.

FIG. 6 shows an example of a specific device configuration. It is the figure which looked at the Bucky imaging stand used at the time of simple photography of a limb, a head, an abdomen, etc. of Examinee S from the longitudinal direction (an overhead direction of a subject). On this table, top 1
The tube T located above the subject S lying on top
X-rays are transmitted through the subject S and the X-rays transmitted through the subject S
To obtain a radiation image.

[0007]

At the medical site, there is a demand for obtaining images of a subject from various directions by a simple operation, and there is an apparatus as shown in FIG. In this apparatus, a cassette 3 containing a film or a stimulable phosphor sheet is covered instead of using the image receiver 2 below the top plate 1 to photograph the side surface of the subject S on the top plate 1. Put it on the side of the examiner S, and from the side X
The X-rays are emitted, and the X-rays transmitted through the subject S are received by the film of the cassette 3.

However, if possible, it is desirable to use the same image receiver regardless of the direction in which the image is taken. In doing so, safety and operability must not be impaired.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in order to meet the above-mentioned demands, and a radiation imaging apparatus according to one aspect of the present invention comprises a top plate on which a subject can be placed and movable in a horizontal direction, A receiver for receiving a radiographic image, a moving mechanism for changing a horizontal position of the receiver with respect to the top plate and a posture of the receiver with respect to the top plate, and a posture of the receiver with respect to the top plate Is provided with a restricting means for restricting movement of the top plate in a predetermined direction when is not horizontal.

According to another aspect of the present invention, there is provided a radiation imaging apparatus comprising: a top plate on which a subject can be placed and movable in a horizontal direction; a receiver for receiving a radiation image of the subject; and a horizontal direction of the receiver relative to the top plate And a moving mechanism for changing the position of the image receiver with respect to the tabletop and a restricting means for restricting a change in the position of the image receiver according to the position of the tabletop.

According to still another aspect of the present invention, there is provided a radiation imaging apparatus comprising: a top plate on which a subject is mounted and movable in a horizontal direction; a receiver for receiving a radiation image of the subject; and a horizontal position of the receiver relative to the top plate. And a moving mechanism for changing the position of the receiver and the attitude of the image receiver with respect to the table, and moving the table in a direction of the image receiver when the image receiver is not horizontal with respect to the table. Or when the position of the image receiver is changed from horizontal when the table is located in a predetermined range, the position between the table and the image receiver is directly It is characterized by having a buffer member for avoiding.

According to still another aspect of the present invention, there is provided a radiation imaging apparatus including a top plate on which a subject is mounted and movable in a horizontal direction, a receiver for receiving a radiation image of the subject, and a horizontal position of the receiver with respect to the top plate. A moving mechanism for changing a position in a direction and a posture of the image receiver with respect to the tabletop, and a method in which the position of the image receiver is not horizontal with respect to the tabletop and the tabletop is in a predetermined range. It is characterized by having limiting means for limiting the movement of the top plate in a predetermined direction.

According to still another aspect of the present invention, there is provided a radiation imaging apparatus comprising: a top plate on which a subject is mounted and movable in a horizontal direction; a receiver for receiving a radiation image of the subject; and a horizontal position of the receiver with respect to the top plate. Direction position, and has a moving mechanism to change the attitude of the image receiver with respect to the top plate,
The moving mechanism includes a mechanism for preventing the horizontal movement of the image receiver when the attitude of the image receiver is not horizontal with respect to the top plate.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings. In the following description, an example in which a digital radiation detector is used as an example of an image receiver that receives a radiation image will be described. However, the present invention is not limited to this, and a cassette containing a radiographic film or a stimulable phosphor sheet is used. Can be replaced with a receiver that uses a.

FIG. 1 is an overall schematic diagram of the radiation imaging apparatus. An X-ray tube, which is an X-ray generator, can be selectively installed at any of the positions T and T ', and projects X-rays toward the subject S from above or from the side. The top plate 101 of the imaging stand such as a table or bed mounts the subject S to be imaged, and is made of an acrylic plate, a carbon plate, or wood. Top board
101 is movably supported on a support 110 in a horizontal plane. An image receiver 113 having a built-in X-ray digital detector is arranged below the top plate 101 and on the upper surface of the support table 110. For a specific example of the X-ray digital detector, see JP-A-8-11604.
See No. 4. Photographer (operator) 10
1 From the bottom, the image receiver 113 is lateral to the subject, that is, the horizontal direction in the horizontal plane (hereinafter, this is defined as “first direction”, and the direction orthogonal to the first direction in the horizontal plane is defined as “second direction”). To be exposed to the outside (state H in FIG. 1), and can be rotated to a vertical state (state V in FIG. 1) after being exposed to the side from inside the top plate 101. It has a moving mechanism. The moving mechanism includes a guide mechanism 114 composed of guide rails for guiding the image receiver 113 in a direction along the horizontal direction of the table 101, and a receiver 11 exposed to the side of the table 101.
And a rotation connection mechanism 115 including a rotation shaft that allows the rotation of the third unit 3 from a horizontal state to a vertical state. The receiver 113 is a top plate 101
Therefore, the subject can be set in any of the horizontal state H and the vertical state V, so that the subject can be imaged by the same image receiver 113 from different directions.

Further, an elevating mechanism capable of moving the top plate 101 up and down and changing the height from the floor is built in the imaging stand. This allows the height of the tabletop to be lowered to a position where the burden on the patient is small when the subject climbs and descends on the tabletop, and that the height of the tabletop is adjusted to a level that is easy for the caregiver to work when transferring from the stretcher. Is possible. In addition, at the time of photographing, the photographing technician can set the height at which it is easy for the photographing technician to perform operations such as positioning of the subject, so that the burden on the photographing technician itself is reduced.

Now, consider a case in which the subject is imaged from the side while the image receiver 113 is pulled out to the side and installed vertically (state V). At this time, the top plate 113 on which the subject is placed
Is greatly moved in the first direction (right direction in the figure).
There is a possibility that the side surface of 101 and the image receiving surface of the image receiver 113 may collide with each other. The mass of the top plate 113 is usually about 30 to 40 kg, and if a subject of 70 kg is put on this, it exceeds 100 kg. Therefore, even if the moving speed is low, the impact at the time of collision is large,
In the worst case, the receiver 113 is damaged or broken. Meanwhile, receiver 1
When the posture of the image receiver 113 is incompletely extracted when the posture of the image receiver 113 is changed when the attitude of the image receiver 113 is changed from the horizontal state (state H) to the vertical state (state V) (that is, the horizontal If it remains under the top plate 101), the edge of the side surface of the top plate 101 may collide with and interfere with the side surface of the image receiver 113, causing the damage or failure of the image receiver 113 at worst. The device of the present embodiment has been devised to solve these problems, and will be described in detail below.

FIG. 2 is a more detailed block diagram of the apparatus shown in FIG. The metal rail 102 is for moving the top plate 101 in the horizontal direction, and a groove is formed inside the rail 102. Linear bearing 104 mounted on movable frame 103
The top plate 101 smoothly and freely moves relative to the subject in a second longitudinal direction (front-back direction in the figure). Further, a linear bearing 105 is provided at a lower portion of the movable frame 103, and the movable frame 103 is moved in a first direction (side direction) with respect to the subject along a shaft 107 attached to a fixed frame 106 fixed to a support table 110. (In the left-right direction in the figure). The combination of the movement in two directions orthogonal to each other in this horizontal plane allows the top plate 101
The operator can move the top board 101 freely on the horizontal plane by hand while the subject S is placed on the top. On the other hand, the movable frame 103 has a lock mechanism 108 for fixing the movement of the rail 102 in the second direction. Similarly, the fixed frame 106 has a lock mechanism 109 for fixing the movement of the movable frame 103 in the first direction. . These lock mechanisms 108 and 109 are respectively connected to the electromagnet 13
1, the top plate 101 can be prevented from freely moving by being magnetically attracted and fixed to the rail 102 / movable frame 103 and locked. The control of the presence or absence of the lock is performed by the first controller 111. In the normal state, the top plate 101 is locked so as not to move in either of the first and second directions. However, if necessary, the lock can be released by the photographer's intention, so that operation is easy and safe. Are compatible. This unlocking operation is performed by a foot technician operating a foot switch 112 including a micro switch provided below the support base 110 as shown in FIG.

On the other hand, as described above, the guide mechanism 114 for horizontally and rotationally moving the image receiver 113 with respect to the top plate 101.
And a rotation connecting member 115. Rotating connection member 115
Is provided with a posture detector 116 composed of a micro switch or a photo interrupter. FIG. 3 is a perspective view of the periphery of the rotation connection member 115, and illustrates the arrangement of the posture detector 116. A rotation connecting member 115 serving as a rotation shaft of the image receiver 113 is provided on the block member 121, and a projection 115a is formed on a cylindrical surface. When the receiver 113 is in the horizontal state, the protrusion 115a is connected to the lever 117 of the microswitch 117.
Press a, and when the receiver 113 is in the vertical state,
So that the micro switch 117 moves away from the lever 117a.
Has been arranged. Thereby, whether the image receiver 113 is in the horizontal state or the vertical state, that is, the attitude of the image receiver 113 with respect to the top plate is detected. The signal from the attitude detector 116 is input to the first controller 111 together with the signal from the foot switch 112 described above. Then, according to the detection result of the attitude detector 116,
The input operation from the foot switch 112 is restricted. Specifically, when the attitude detector 116 detects that the image receiver 113 is in the vertical state, the first controller 111 moves the top 101 without releasing the lock even if the foot switch 112 is operated. Ban. Conversely, when the attitude detector 116 detects that the image receiver 113 is in the horizontal state, the lock is released in accordance with the input from the foot switch 112, and control is performed so that the top board 101 can be moved.

When the subject is placed on the top 101 and the image is taken from above, the image receiver 113 is positioned horizontally below the top 101. The horizontal state of the image receiver means that the attitude detector 11
Since the operation is performed at step 6 and the operation of the foot switch 112 is enabled, the top panel 101 can be moved if the operator releases the lock. On the other hand, when the subject is imaged from the side, the attitude of the image receiver 113 is switched from the horizontal state to the vertical state after the image receiver 113 is fully pulled out to the side (first direction) of the top board 101. The fact that the receiver 113 is in the vertical state indicates that the attitude detector 1
Since the detection is performed at 16, the lock is not released even if the foot switch 112 is pressed under the control of the first controller 111. Since the operator cannot move the top plate 101 even when trying to move it, it is prevented from colliding with the image receiver 113 by mistake. In addition, since the top plate 101 does not interfere with the image receiver 113 even when the top plate 101 is moved in the second direction, instead of locking both the first direction and the second direction of the top plate 101 as a modification, only the first direction is used. Lock control, that is, only the lock mechanism 119 is controlled and the lock mechanism 118 is not controlled, and the second direction may be movable independently of the attitude of the image receiver 113. In this way, even if the image receiver 113 is in the vertical state, the photographer can
Can be moved only in the second direction, and the imaging region can be changed or corrected in this direction.

Note that the image receiver 113 which is in the vertical state
However, if it is possible to move in the horizontal direction (first direction), the image receiver 113 may collide with the side surface of the top plate 101. In order to prevent this, the moving mechanism of the image receiver 113 has a lock structure such that it cannot be moved in the horizontal direction when the image receiver 113 is in a vertical state. This may be a mechanical locking mechanism or an electromagnetic locking mechanism using a sensor and electromagnetic means (actuator or solenoid).

On the other hand, as described above, when rotating the image receiver 113 from the horizontal state to the vertical state to change the attitude of the image receiver 113, the image receiver 113 may collide with the side surface of the top plate 101. The device of the present embodiment also has a mechanism for preventing this before it occurs. 2, the position detector 118 detects the position of the movable frame 103. Movable frame 103 and top plate 10
The positional relationship with 1 changes in the second direction due to the movement of the top 101, but does not change in the first direction. As a result, the position detector 118 detects the position of the top 101 in the first direction. Will be. The position detector 118 has a micro switch 119, and a lever 119a extending from the micro switch 119 detects the movement of the movable frame 103. When the top plate 101 is in a positional relationship that does not interfere with the image receiver 113 in the vertical state, the lever 119a is pushed on the bottom surface of the movable frame 103 to be turned ON. On the other hand, in a positional relationship where the top plate 101 interferes with the vertical image receiver 113, the lever 119a is disengaged from the bottom surface of the movable frame 103, and the switch is turned off. Thus, the position detector 118 detects the allowable range of the movement of the top board 101 in the first direction when the image receiver 113 is vertical.

Further, a rotation lock mechanism 120 is provided near the rotation connecting member 115 for rotating the image receiver 113 to change the attitude. This changes the receiver 113 from a horizontal state to a vertical state.
This rotation is restricted when the posture is switched, and has a structure as shown in FIG. In the figure, a block member 121 attached to an image receiver 113 is a rotation connecting member.
It has a hole 121a for fixing 115. In opposition to this, a solenoid 122 is disposed on the guide mechanism 114, and the image receiving device 11
When 3 is in the horizontal state, the hole 121a of the block member 121 and the linear motion shaft 122a of the solenoid 122 match. The solenoid 122 is driven by the second controller 123, and locks the rotation of the block member 121 by inserting the linear motion shaft 122a into the hole 121a.
The posture change from the horizontal state to the vertical state cannot be performed.

The signal from the position detector 118 is also input to the second controller 123, and controls the rotation lock mechanism 120 based on the detection by the position detector 118. Position detector 118 is ON
In other words, when the top board 101 is located at a position where the top board 101 and the image receiver 113 do not interfere with each other as shown in FIG. 2, the rotation lock is released, and the photographing technician changes the attitude of the image receiver 113 as necessary. It can be performed. Conversely, when the position detector 118 detects OFF, that is, when the top plate 101 is at a position where the top plate 101 and the image receiver 113 interfere with each other, the rotation is locked by the driving of the solenoid, and the rotation of the image The posture cannot be changed, and interference with the side surface (rail 102) of the top plate 101 does not occur. When the image receiver 113 is set in the vertical state, the top plate 101 is moved to a position where it does not interfere with the top plate 101 and released, whereby the solenoid 122 is driven to change the posture.

In the above example, when the image receiver 113 is in the vertical state, at least the movement of the top plate 101 in the first direction is completely locked.
By using the signal of 8, the top plate 101 is prevented from entering a range where interference with the image receiver 113 occurs, and the top plate 101 can be moved in the first direction and the second direction in other ranges. You may. Specifically, it is realized by logic for operating the lock mechanism 109 when the detection of the position detector 118 is turned off. Accordingly, even when the image receiver 113 is in the vertical state, the movable range of the top plate 101 is widened, and positioning of the subject becomes easier.

FIG. 5 shows a modification of the above example. In the above example, when the attitude of the receiver is not horizontal with respect to the top, the movement of the top in the lateral direction is restricted, or the solenoid is driven according to the position of the top to rotate the receiver. In contrast, in the example of FIG. 5, instead of restricting the movement of the top plate and the rotation of the image receiver, a protection means including a cushioning member is provided to restrict the posture change of the top plate 101. The edge of the side face is prevented from directly colliding with the image receiving surface of the image receiver 113.

A specific mechanism will be described below. As shown in FIG. 5, a small buffer member 132 is fixed to the block member 121, and its head projects beyond the outer frame and the image receiving surface of the image receiver 131. The cushioning member 132 is made of, for example, a material having flexibility such as rubber at least at its head or absorbing a shock by a shock absorber using a spring. As another form, a mechanism may be used in which the buffer member is protruded by the actuator based on the signal of the attitude detector 141. The buffer member 132 is provided at a position where the head of the buffer member is at the same height as the top plate 101 when the attitude of the image receiver 113 is changed to the vertical state. This temporarily creates a top plate
Even if the operator erroneously switches the receiver 131 from horizontal to vertical while the 101 is moved to the side, the head of the cushioning member 132 hits the side of the top plate 101 to absorb the impact, and the momentum The plate 101 is pushed back to a range where there is no interference. on the other hand,
Even if the operating technician erroneously moves the top plate 101 to the side when the image receiver 113 is in the vertical state, an indirect collision via the cushioning material occurs. For this reason, there is no direct impact on the image receiver 113, and damage or failure of the image receiving surface can be avoided. Note that the buffer member 132 may be provided on the top plate 101 side without being provided on the image receiver 113 side. That is, a buffering member may be provided at a position on the side surface of the top plate 101 that does not interfere with the image receiving surface of the image receiver 113, and at a position where direct collision between the image receiving surface of the image receiver 113 and the side surface of the top plate 101 is avoided. What is necessary is just to provide an interference member.

[0028]

According to the present invention, there is provided a radiation imaging apparatus having a movable top plate and a receiver capable of changing its position and attitude with respect to the top plate, the damage or failure due to interference between the top plate and the receiver. Can be prevented beforehand, and a highly reliable and safe device can be provided.

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram of an embodiment of a radiation imaging apparatus.

FIG. 2 is a detailed configuration diagram of the apparatus of FIG. 1;

FIG. 3 is a partial configuration diagram of the apparatus of FIG. 1;

FIG. 4 is a partial configuration diagram of the apparatus of FIG. 1;

FIG. 5 is a partial configuration diagram of a modified example.

FIG. 6 is a configuration diagram of a conventional example.

FIG. 7 is a configuration diagram of a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Top plate 102 Rail 103 Movable frame 104 First linear bearing 105 Second linear bearing 106 Fixed frame 108, 109 Lock mechanism 110 Support stand 111 First controller 112 Foot switch 113 Image receiver 114 Guide mechanism 115 Rotary connection member 116 Posture detection Device 118 Position detector 120 Rotation lock mechanism 121 Block member 122 Solenoid 123 Second controller 130 Moving mechanism 131 Electromagnet 132 Buffer member

Claims (18)

[Claims] 1. A top plate on which a subject is placed and movable in a horizontal direction; an image receiver for receiving a radiation image of the subject; a horizontal position of the image receiver with respect to the top plate; and the image receiver with respect to the top plate A radiographic system, comprising: a moving mechanism that changes a posture of the receiver; and limiting means that restricts movement of the top plate in a predetermined direction when the posture of the image receiver is not horizontal with respect to the top plate. apparatus. 2. The apparatus according to claim 1, wherein the restricting unit has a detector for detecting a posture of the image receiver, and restricts a movement of the tabletop based on the detection of the detector. Radiography equipment. 3. The moving mechanism according to claim 2, wherein the moving mechanism allows the image receiver to move horizontally in a lateral direction with respect to a subject, and enables the attitude of the image receiver to be either horizontal or vertical. The radiation imaging apparatus according to claim 1, wherein 4. The radiation imaging apparatus according to claim 3, wherein said restricting means restricts lateral movement of said top plate. 5. A top plate on which a subject is placed and movable in a horizontal direction; an image receiver for receiving a radiation image of the subject; a horizontal position of the image receiver with respect to the top plate; and the image receiver with respect to the top plate A radiographic apparatus comprising: a moving mechanism that changes a posture of the image receiver; and a restricting unit that restricts a change in the posture of the image receiver in accordance with a position of the top plate. 6. The apparatus according to claim 5, wherein the restricting unit has a detector for detecting a position of the top plate, and restricts a change in attitude of the image receiver based on the detection of the detector. Radiation imaging equipment. 7. The moving mechanism according to claim 1, wherein the image receiving device is horizontally movable with respect to a subject in a lateral direction, and the attitude of the image receiving device is set to be either horizontal or vertical. The radiation imaging apparatus according to claim 5, wherein: 8. The radiation imaging apparatus according to claim 7, wherein the limiting unit limits the attitude of the image receiver from horizontal to vertical. 9. A top plate on which a subject is placed and movable in a horizontal direction; an image receiver for receiving a radiation image of the subject; a horizontal position of the image receiver with respect to the top plate; and the image receiver with respect to the top plate A moving mechanism for changing the posture of the table, and restricting the movement of the table in a predetermined direction when the position of the image receiver is not horizontal with respect to the table and the table is in a predetermined range. A radiation imaging apparatus comprising: a limiting unit. 10. A limiting device comprising: a first detector for detecting an attitude of the image receiver; and a second detector for detecting a position of the top plate.
10. The apparatus according to claim 9, further comprising a detector, wherein the movement of the top plate is restricted based on the detection of the first and second detectors.
A radiation imaging apparatus according to claim 1. 11. The moving mechanism enables the image receiver to be horizontally movable in a lateral direction with respect to a subject, and enables the attitude of the image receiver to be either horizontal or vertical. The radiation imaging apparatus according to claim 10, wherein 12. The radiation imaging apparatus according to claim 11, wherein said restricting means restricts lateral movement of said top plate. 13. A top plate on which a subject is placed and movable in a horizontal direction; an image receiver for receiving a radiation image of the subject; a horizontal position of the image receiver with respect to the top plate; and the image receiver with respect to the top plate A moving mechanism that makes the posture of the receiver variable, and when the top is moved in a certain direction of the image receiver when the posture of the image receiver is not horizontal with respect to the top, or the top is in a predetermined range. When the attitude of the image receiver is changed from horizontal when it is located at a position, the radiation member is provided between the top plate and the image receiver to avoid a direct collision between them. Shooting equipment. 14. A top plate on which a subject is placed and movable in a horizontal direction, an image receiver for receiving a radiation image of the subject, a position of the image receiver with respect to the top plate in a horizontal direction, and the image reception on the top plate A moving mechanism for changing a posture of the receiver, wherein the moving mechanism includes a mechanism for preventing the horizontal movement of the receiver when the posture of the receiver is not horizontal with respect to the top plate. A radiographic apparatus characterized by the above-mentioned. 15. The radiation imaging apparatus according to claim 1, further comprising an elevating mechanism for elevating the top plate. 16. The radiation imaging apparatus according to claim 1, wherein the radiation is X-rays. 17. The radiation imaging apparatus according to claim 16, further comprising an X-ray generator that generates X-rays. 18. The radiographic film according to claim 18,
17. The radiation imaging apparatus according to claim 16, comprising one of a storage phosphor detector and a digital radiation detector.