JP3518573B2 - X-ray inspection equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to an X-ray inspection apparatus used for medical diagnosis and the like, and more particularly to an X-ray apparatus capable of freely determining the X-ray fluoroscopic direction and position. The present invention relates to a line inspection device. 2. Description of the Related Art Conventionally, an X-ray image system (comprising an X-ray tube, an image intensifier, a television camera, etc.) is held by a mechanism combining various mechanisms such as a linear motion mechanism and a rotary motion mechanism. An X-ray inspection apparatus is known in which an X-ray fluoroscopic direction and position are freely determined by changing the position and direction of an X-ray beam (perspective field) with respect to a subject. In such an X-ray inspection apparatus, in order to prevent the respective movements of the mechanisms from interfering with each other or colliding with the subject, the movements in other movement axes are considered in each of the various movement directions. The operation is controlled. In this case, after setting a target final position and direction, an operation start switch is pressed and the set position and direction are set.
It is configured to start operation in each motion axis in the direction, and when the lever is tilted, it moves in the direction in which it is tilted, at a speed according to the tilt angle, and by operating the lever There is a method of performing various trials by arbitrarily moving and determining an optimum position and angle. [0004] However, the conventional X-ray inspection apparatus has a problem that it is inconvenient depending on how to use it. That is, in the usage method in which the final position / direction is set and the operation is performed in each axis toward it, the final position / direction cannot be set in the interference area in consideration of the interference in each axis. When setting the final position / direction in the warning area near the interference area, start moving toward it and accidentally enter the interference area when approaching the target position / direction in the warning area. It is possible to perform control such as lowering the speed so as not to make it go away. However, if the user moves the lever arbitrarily without determining the final position and direction, it is not possible to know where the final position and direction will be. There is a danger of entering (because it cannot be stopped suddenly due to inertia). Therefore, in such a usage in which the lever is arbitrarily moved by lever operation or the like, the operation time at a low speed is increased for danger avoidance, resulting in poor operability and inconvenience. In view of the above, the present invention predicts the amount of movement when arbitrarily moving by lever operation or the like, and decelerates only when the predicted position / direction falls within the interference area. Thus, an object of the present invention is to provide an X-ray inspection apparatus in which the operation time at low speed is shortened and the operability is improved. In order to achieve the above object, in an X-ray inspection apparatus according to the present invention, an X-ray imaging device and the X-ray imaging device are moved in respective directions of a plurality of axes. Moving means for moving, a lever which can be tilted at an arbitrary angle in any direction corresponding to each axis of the movement of the X-ray imaging means, and a tilt angle in the tilt direction of the lever following the movement of the lever Control means for controlling the moving means so as to move the X-ray imaging means at a speed corresponding to the above, means for detecting the position of the X-ray imaging means in each direction at regular time intervals, and A means for holding information indicating a restricted area for the movement of the means, and a movement distance obtained based on the current speed to the current detection position, and the expected position at the next detection time and when decelerating and stopping there And a means for performing a deceleration stop operation by comparing the expected stop position with the above-described restricted area information. [0007] When the lever is operated, following it,
That is, the X-ray imaging unit moves at a speed corresponding to the tilt angle in the direction in which the lever is tilted. The position of the moving X-ray imaging means (the position in each direction) is detected at regular intervals. As a result, when the current position is detected, the position to be stopped by the deceleration stop started at the next detection time is predicted, and it is determined whether or not the predicted stop position is within the restricted area. Start the deceleration stop operation. That is, the X-ray imaging means can be moved in a free direction and at a free speed until it is determined that the stop position when the deceleration stop operation is started after a certain period of time in the future will enter the restricted area. . Therefore, it can be moved quickly and the operability is improved. In addition, the deceleration stop operation is performed in response to the stop position of the deceleration stop operation that is started at the next detection time entering the restricted area. The risk of entering the restricted area in a timely manner is avoided, and safety is enhanced. Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of a control system of an X-ray inspection apparatus according to an embodiment of the present invention. The X-ray inspection apparatus is as shown in FIG. That is, this X-ray inspection apparatus is a type of C-arm type X-ray fluoroscope, and is of a type that can be used for inspection of a circulatory organ. For convenience of explanation,
FIG. 2 will be described. In FIG. 2, a television camera 23 is attached to an X-ray tube 21 and an image intensifier (II) 22.
Are attached to both ends of the C-arm 24, and the bed top plate 11 for laying down the subject is arranged between them. The C-arm 24 is held by an arm holding block 25, and the arm holding block 25 is attached to a slide block 26. The slide block 26 is a slide rail 27
The slide rail 27 is attached to a semicircular upside down frame 28. The raising frame 28 is held by a base 29. The bed top plate 11 is attached to the upside-down frame 28. The operation (moving direction) of each part will be described.
Is held so as to be able to rotate in the direction of arrow 08 along the semicircle of the arrow. Therefore, when the frame 28 rotates, the bed top plate 11 also rotates integrally therewith. The bed top plate 11 can be moved in the directions indicated by arrows 01, 02, and 03 while being held by the tilting frame 28. In other words, the right and left direction of the bed top plate 11 (the left and right direction of the subject lying thereon) 01, the length direction of the bed top plate 11 (the height direction of the subject) 02, and the plane perpendicular to the surface of the bed top plate 11 It can move in the direction 03. These directions 01, 02, and 03 correspond to the X direction, the Y direction, and the Z direction which is the vertical direction in the horizontal plane in the state shown in the figure, but rotate with the rotation of the tilting frame 28. . [0011] The slide block 26 is a
8 can be moved linearly along the slide rail 27 fixed to 8 as indicated by an arrow 07. The direction of the arrow 07 rotates with the rotation of the tilting frame 28. Then, the arm holding block 25 is held by the slide block 26 so as to be rotatable in the arrow 06 direction. That is, the arm holding block 25 is
It is rotatable around an axis (horizontal axis) perpendicular to (sliding direction indicated by arrow 07). The C-shaped arm 24 is held by the arm holding block 25 so as to be rotatable in the direction of arrow 05 along the C-shape. Therefore, the direction of the X-ray beam emitted from the X-ray tube 21 and incident on the image intensifier 22 is rotatable around three axes as indicated by arrows 05, 06 and 08, and the position of the X-ray beam is Can be moved linearly with respect to the bed top plate 11 (the subject thereon) as indicated by an arrow 07. Further, the image intensifier 22 and the television camera 23 coupled thereto are
At the tip of the mold arm 24, it can move linearly as shown by an arrow 04 to approach or move away from the X-ray tube 21. In this X-ray inspection apparatus, there are eight moving axes as described above, and the position and direction of the X-ray beam can be arbitrarily determined by freely moving with these eight axes. The control system for the movement in these eight axes is configured as shown in FIG. FIG. 1 shows only a control system for movement of the C-arm 24 in the directions of arrows 05 and 06. The direction of arrow 05 is the direction of rotation around the body axis of the subject lying on the bed top 11 and is called the LAO-RAO direction, and the direction of arrow 06 is within a vertical plane including the body axis of the subject. The direction of rotation is called the CRAN-CAUD direction. In FIG. 1, a joystick-like lever 41 for operating the C-arm 24 is provided on an operation panel 40.
Is provided. When the lever 41 is tilted in the LAO-RAO direction or the CRAN-CAUD direction (or an intermediate direction thereof), the tilt angle in the LAO-RAO direction is changed by the angle detector 42 to the tilt angle in the CRAN-CAUD direction. The angles are detected by the angle detectors 43, and the detection outputs are input to the CPU 31. These angle detectors 42 and 43 are constituted by potentiometers and the like. As described above, since information regarding the tilt direction and angle of the lever 41 is input to the CPU 31, the CPU 31 generates a movement command while referring to the operation range table (shown in FIG. 4) stored in the memory 37. The signal is input to the driving device 33 via the D / A converter 32, and the motor 34 is rotated. The movement command is generated for each of the LAO-RAO direction and the CRAN-CAUD direction,
Each motor 34 causes the C-arm 24 to move in those directions. The rotation direction of the motor 34 in each direction corresponds to the tilt direction of the lever 41 in each direction, and the rotation speed corresponds to the angle in each direction. On the other hand, the position in each direction is detected at a fixed sampling time interval by a position detector 35 composed of a potentiometer or the like, and sent to the CPU 31 via an A / D converter 36. The CPU 31
As shown in the flowchart of FIG. 3, a future position is predicted based on the detected information on the current position and the current moving speed, and control is performed by comparing the predicted position with an operation range table in the memory 37. . As shown in FIG. 4, this operating range table shows the possibility of collision with the bed top plate 11 and the examinee thereon when tilted at a certain angle or more in both the LAO-RAO direction and the CRAN-CAUD direction. This shows a certain collision area 51 and a warning area 52 in the vicinity thereof. These regions 51 and 52 can be determined in advance if the mechanism as shown in FIG. 2 is determined. Since the collision area 51 and the warning area 52 change depending on the position of the bed top 11,
It is desirable to prepare an operation range table as shown in FIG. 4 for each position of the bed top plate 11, or to make corrections according to the position of the bed top plate 11. The operation of the lever 41 causes the C-arm 24
Are moved, and the trajectory becomes like an arrow 61 on the operation range table of FIG. CPU31
When the predicted future position enters the collision area 51 or the warning area 52, the CPU 31 issues a command for a sudden stop or a deceleration stop operation to stop the motor 34 suddenly or decelerate. This will be described in detail with reference to the flowchart of FIG. First, the current position is A as shown in FIG. 5, and if this position A is detected, if the vehicle immediately starts decelerating and stopping at this position A, the moving distance b required from the current speed to the stop is Is calculated. Next, an expected moving distance c until the next sampling time is calculated based on the current speed. By adding this distance c to the current position A, the position C that will have reached at the next sampling is known (see FIG. 5). Further, by adding the deceleration movement distance b to the position C, an expected stop position D (FIG. 5) at the time of immediately decelerating and stopping at the position of the next sampling is obtained (the same as the present at the next sampling). Assuming you are moving at speed). Then, the predicted stop position D is compared with the operation range table, and it is determined whether stop preparation is necessary based on whether or not the position D is within the warning area 52. If it is determined that the position D has not entered the warning area 52 and preparation for stopping is not necessary, the operation of detecting the current position is performed again after a predetermined sampling time has elapsed. When it is determined that the stop preparation is necessary because the position D is in the warning area 52, an expected stop position B (FIG. 5) when the deceleration stop operation is immediately started at the current position is obtained. This is calculated by adding the deceleration movement distance b obtained as described above to the current position A (see FIG. 5). Then, the position B is compared with the operation range table, and it is determined whether or not the sudden stop is necessary based on whether or not the position B is in the collision area 51. If it is determined that the position B is in the collision area 51 and an abrupt stop is required, an abrupt stop operation command is issued immediately. Otherwise, a deceleration stop command is issued and the C-arm 24 decelerates and stops. At this time, the expected stop position D in the future is the warning area 5
Since the position B is determined to be in the collision area 51, the position B normally does not enter the collision area 51, and therefore, the deceleration stop operation is performed. And
This deceleration stop always stops before the collision area 51, which is safe. Such a sudden stop is an exception, and the expected stop position D in the future is usually the warning area 52.
In other words, conversely, the expected stop position D at the future time is changed to the warning area 5.
Until the movement enters 2, the movement of the lever 41 can be performed at an increased speed by free operation, and good operability can be maintained. The above description and FIG. 5 show the LAO-R
Although the description has been made with respect to either the AO direction or the CRAN-CAUD direction, the above-described operation is actually performed in each of the two directions. Although only the movement of the C-arm 24 has been described above, the X-ray inspection apparatus having the mechanism shown in FIG. It can be configured as follows. Further, the information indicating the operation range (restricted area such as a collision area or a warning area) is not limited to being held in the above-described table format. As described above, according to the X-ray inspection apparatus of the present invention, the lever is operated and follows the operation, that is, at the speed corresponding to the inclination angle in the inclination direction. , The X-ray imaging means can be moved, and in such a case following the lever operation, if a deceleration stop operation is started after a certain time from the present time, a position that will be stopped is predicted, The deceleration stop operation is performed by determining that the predicted stop position enters the restriction area. In other words, since the deceleration stop operation starts according to the expected stop position in the future,
The deceleration stop operation is started with ample time at an early point, and it is possible to avoid a dangerous situation from a delay in the start of the deceleration stop operation, thereby enhancing safety. As described above, since the deceleration stop operation is started at an early point and the safety is enhanced, it is safe to move at an arbitrarily high speed, and it is possible to freely move at a high speed. The operability does not deteriorate.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a control system of an X-ray inspection apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view schematically showing the entire appearance of the X-ray inspection apparatus. FIG. 3 is a flowchart illustrating an operation. FIG. 4 is a diagram showing an operation range table. FIG. 5 is a diagram showing each position. [Explanation of Signs] 11
Bed top plate 21
X-ray tube 22
Image intensifier 23
TV camera 24
C-arm 25
Arm holding block 26
Slide block 27
Slide rail 28
Semicircular falling frame 29
Base 31
CPU 32
D / A converter 33
Drive unit 34
Motor 35
Position detector 36
A / D converter 40
Operation panel 41
Lever 42, 43 Angle detector 51
Collision area 52
Warning area 61
Trajectory

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hirotaka Isono 1 Shiwazu Works, Sanjo Plant, Nishinokyo Kuwabaracho, Nakagyo-ku, Kyoto-shi, Kyoto (56) References JP-A-4-245598 (JP, A) 1-161710 (JP, U) WO 96/03078 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61B 6/00-6/14

Claims (1)

(57) Claims 1. X-ray imaging means, moving means for moving the X-ray imaging means in respective directions of a plurality of axes, and X-ray imaging means A lever capable of being tilted at an arbitrary angle in a corresponding direction, and a movement following the movement of the lever to move the X-ray imaging means at a speed corresponding to the tilt angle in the tilt direction of the lever. Control means for controlling the means, means for detecting the position of the X-ray imaging means in each direction at regular time intervals, means for holding information representing a restricted area for movement of the X-ray imaging means, Means for obtaining the expected position at the next detection time and the expected stop position when decelerating and stopping thereat by adding the moving distance obtained based on the current speed to the current detection position, Pair with restricted area information X-ray examination apparatus, characterized in that it comprises a means for causing a deceleration stop operation by.