JP2010194152A - Radiographic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of interfaces for positioning a radiation source in a radiographic apparatus. <P>SOLUTION: The radiographic apparatus includes the radiation source 16; a radiation detecting means; a radiographic element mounting part in which the radiation source 16 is mounted; first, second and third drive parts 33, 43 and 52 for moving the radiographic element mounting part in three-dimensional directions; and a rotationally holding means for switching the position of the radiographic element mounted part held in a guide mechanism to a plurality of rotational positions to change the direction of the radiation exposure axis. The radiographic apparatus also includes: first operating parts 21 and 91 and second operating parts 22 and 92 for adjusting the direction and quantity of driving of one or two of the first-third driving parts 33, 43 and 53; a rotation position detecting means 64 for detecting the rotation position of the radiographic element mounting part; and a control means 30 for selecting a target driving part to be operated from the first-third driving parts 33, 43 and 53, for the first operating parts 21 and 91 and the second operating parts 22 and 92 to adjust the direction and quantity of driving, respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a radiation imaging apparatus in which radiation is emitted from a radiation source toward a subject and the radiation transmitted therethrough is detected by a radiation detection means, and more specifically, the radiation source or the radiation detection means. The present invention relates to a radiographic apparatus having an improved configuration relating to positioning.

  2. Description of the Related Art Conventionally, as shown in, for example, Patent Document 1, a radiation imaging apparatus including a radiation source that irradiates a subject with radiation such as X-rays and radiation detection means that detects radiation transmitted through the subject. Is known. As the radiation detection means, a silver salt photographic film such as an X-ray film, a radiation conversion panel (storable phosphor sheet), a radiation solid detector, etc. shown in Patent Document 1 are known. .

  In this type of radiation imaging apparatus, as shown in Patent Documents 2 and 3 as an example, both or one of the radiation source and the radiation detection means suspended from the ceiling is moved in a two-dimensional direction within a horizontal plane. It has been proposed to improve the workability and efficiency of radiography by making it freely and further moving in the vertical direction. In many cases, such a radiation imaging apparatus basically includes a rail fixed to a ceiling in a state extending in one horizontal direction (Y direction), a Y-axis traveling unit that moves along the rail, and the Y-axis. A rail fixed in a state extending in the horizontal direction (X direction) perpendicular to the Y direction to the traveling unit, an X axis traveling unit moving along the rail, and a downward direction (Z direction) from the X axis traveling unit It is composed of an extendable portion that is variable in length and has a radiation source or radiation detection means mounted on the extendable portion.

  By the way, in order to move the radiation source or the radiation detection means in the three-dimensional direction and position it at a predetermined position as described above, an interface for controlling the three-dimensional movement is required. When particularly precise positioning is required, for example, as disclosed in Patent Document 4, a fine movement interface for moving the radiation source or the radiation detection means by a minute amount is often provided.

JP 2008-167948 A JP 2002-065655 A JP-T-2007-527763 JP 2002-045353 A

  Conventionally, three interfaces are usually provided corresponding to the driving means responsible for each movement in the three-dimensional direction. However, in actual radiography, especially in the case of precise positioning, the radiation source is mostly moved in a two-dimensional direction along the detection surface of the radiation detection means, and if so, three interfaces are provided. There may be situations where the radiographer is at a loss as to which of these two to use.

  Here, a general radiation imaging apparatus is often capable of supporting both standing-up imaging and lying-down imaging by changing the direction of the radiation irradiation axis and further imaging. Therefore, in each actual imaging, it is necessary to make the radiation source moving means movable in the three-dimensional direction even if the radiation source is moved only in the two-dimensional direction. In the past, only two interfaces were installed.

  The present invention has been made in view of the above circumstances, and can cope with a plurality of imaging methods in which the orientation of the radiation source or the radiation detection means is changed, while the movement for positioning the radiation source or the radiation detection means. An object of the present invention is to provide a radiation imaging apparatus capable of improving the operability by reducing the number of interfaces for controlling the camera.

The radiographic apparatus according to the present invention is:
A radiation source that emits radiation toward the subject;
Radiation detecting means for detecting radiation transmitted through the subject;
An imaging element mounting portion on which the radiation detection means or the radiation source is mounted;
A guide mechanism that holds the photographing element mounting portion so as to be movable in X, Y, and Z directions orthogonal to each other;
First, second, and third drive units that individually move the imaging element mounting unit along the guide mechanism in each of the X, Y, and Z directions;
In the radiation imaging apparatus comprising rotation holding means that can switch and set the imaging element mounting portion held by the guide mechanism to a plurality of rotation positions so as to change the radiation exposure axis direction,
First and second operation units (interfaces) each adjusting the driving direction and driving amount of one or two of the first to third driving units;
Rotational position detecting means for detecting the rotational position of the imaging element mounting unit;
In accordance with the rotational position detected by the rotational position detecting means, the first and second operation units, among the first to third drive units, each have an operation target drive unit that adjusts the drive direction and the drive amount. The control means to select is provided.

More preferably in the radiographic apparatus having the above-described configuration,
The rotation holding means sets the imaging element mounting portion to the Z direction as a vertical direction, a first rotation position where the radiation exposure axis direction is the Z direction, and a second rotation where the radiation exposure axis direction is the Y direction. Is supposed to be set to position,
When the control unit detects the first rotation position by the rotation position detection unit, one of the first and second drive units as each operation target drive unit of the first and second operation units, When the other rotation position is selected and the second rotation position is detected by the rotation position detection means, one of the first and third drive units as each operation target drive unit of the first and second operation units, The other is selected.

Alternatively, in the radiation imaging apparatus of the present invention,
The rotation holding means sets the imaging element mounting portion as the Z direction as a vertical direction, a first rotation position where the radiation exposure axis direction is the Z direction, and the radiation exposure axis direction is intermediate between the Y direction and the Z direction. It is supposed to be set to the second rotation position that becomes the direction,
When the control unit detects the first rotation position by the rotation position detection unit, one of the first and second drive units as each operation target drive unit of the first and second operation units, When the other is selected and the second rotational position is detected by the rotational position detecting means, the first drive unit, the second and the third are used as the operation target drive units of the first and second operation units. One of the driving units may be selected.

And in each configuration as described above,
As said 1st, 2nd operation part, what has each a movable part which moves to a linear direction at least in part is used,
These movable parts are configured to change the orientation in the linear direction by changing the posture in conjunction with the rotation of the imaging element mounting part,
When the imaging element mounting unit is in each of the first rotation position and the second rotation position, the linear direction of the movement of the movable unit of the first and second operation units is determined by the operation target drive unit of each operation unit. It is desirable that the movable portion is disposed so as to be aligned with the moving direction of the imaging element mounting portion.

  The first and second operation units are preferably configured to change the drive direction of the operation target drive unit according to the direction of movement of the movable unit.

  In addition, it is desirable that each movable part of the first and second operation parts is made of a disk-like member that rotates about the central axis. When such a configuration is adopted, the movable parts made of the disk-like members of the first and second operation parts are arranged in the direction of the central axis with their central axes aligned. desirable. When the movable part is arranged in such a manner, the movable part is attached to the rod-shaped portion constituting the handle integrated with the photographing element mounting portion with the long axis and the central axis of the rod-shaped portion aligned. It is particularly desirable that

  In the radiation imaging apparatus of the present invention, the moving direction of the imaging element mounting unit that is moved by the operation target drive unit of each operation unit in correspondence with each movable unit of the first and second operation units is set as described above. It is desirable that display means for switching display according to the rotation position switching of the imaging element mounting unit is provided.

  More specifically, as the display means as described above, it is possible to employ a display that indicates the moving direction of the photographing element mounting portion by characters or a specific color that is determined according to the moving direction. When the display means having the latter configuration is adopted, a moving direction guide display is provided in the vicinity of the guide mechanism to indicate the moving direction of the photographing element mounting portion corresponding to each of the unique colors in the same color as the color. It is preferred that

  On the other hand, in the radiographic apparatus of the present invention, the control means stops the function of the other operation unit when one of the first and second operation units is operated, and operates the one operation unit. It is desirable that the function of the other operation unit is restored when it is detected that the operation has ended. More specifically, it is preferable that such a control means detects that one of the operations of the first and second operation units is completed when a predetermined time elapses after the operation is stopped. Can be used.

  In more detail, the radiation imaging apparatus of the present invention has the radiation exposure axis direction when the imaging element mounting unit mounts the radiation source and the rotational position of the imaging element mounting unit is changed. The irradiation axis direction of the radiation source is configured to change.

  Alternatively, in the radiation imaging apparatus of the present invention, the imaging element mounting unit is mounted with the radiation detection unit, and the rotation position of the imaging element mounting unit is changed, whereby the radiation detection unit that is in the radiation exposure axis direction. The detection surface normal direction may be changed.

  As described above, the radiation imaging apparatus of the present invention includes first and second operation units (interfaces) that adjust the driving direction and driving amount of one or two of the first to third driving units, respectively. Rotation position detection means for detecting the rotation position of the photographing element mounting section, and the first and second driving units among the first to third drive sections according to the rotation position detected by the rotation position detection means. Since the operation unit includes a control unit that selects an operation target drive unit that adjusts the drive direction and the drive amount, an interface that controls movement of the radiation source or the radiation detection unit for two-dimensional positioning is provided. It is possible to cope with a plurality of photographings in which the radiation irradiation direction is changed while keeping the minimum two.

  If the number of interfaces is two in correspondence with the two-dimensional positioning of the radiation source or the radiation detection means, it is possible to prevent a situation in which the imaging engineer is at a loss as to which interface should be used for radiography. If so, it is possible to position a radiation source or the like with good operability and perform many imagings in a short time even when imaging emergency patients that require urgent imaging.

In the radiographic apparatus of the present invention, in particular,
As said 1st, 2nd operation part, what has each a movable part which moves to a linear direction at least in part is used,
These movable parts are configured to change the orientation in the linear direction by changing the posture in conjunction with the rotation of the imaging element mounting part,
When the imaging element mounting unit is in each of the first rotation position and the second rotation position, the linear direction of the movement of the movable unit of the first and second operation units is determined by the operation target drive unit of each operation unit. When the movable part is arranged so as to match the moving direction of the imaging element mounting part,
Since the operator can intuitively know which movable part should be operated in which direction to move the radiation source or the radiation detection means, the operability is further improved.

  In the radiation imaging apparatus of the present invention, the imaging direction of the imaging element mounting unit that is moved by the operation target drive unit of each operation unit in correspondence with each movable unit of the first and second operation units is determined by the imaging. When there is provided a display means for switching display according to the rotation position switching of the element mounting part, it is clearly shown which movable part should be operated in which direction to move the radiation source or radiation detection means. The operability is further improved.

1 is an overall perspective view showing a radiation imaging apparatus according to an embodiment of the present invention. The perspective view which expands and shows a part of the said radiography apparatus Block diagram showing the electrical configuration of the radiation imaging apparatus The perspective view which shows the operation part in the said radiography apparatus The perspective view which shows the operation part in the said radiography apparatus Side view showing the imaging state of the radiation imaging apparatus The perspective view which shows the mode of the operation part in the state of FIG. Side view showing another imaging state of the radiation imaging apparatus The perspective view which shows the mode of the operation part in the state of FIG. Side view showing still another imaging state of the radiation imaging apparatus The perspective view which shows the mode of the operation part in the state of FIG. Side view showing still another imaging state of the radiation imaging apparatus The perspective view which shows the mode of the operation part in the state of FIG. The figure explaining the rotation state of the operation block in the said radiography apparatus The graph which shows the characteristic of the operation part in the said embodiment The flowchart which shows the flow of the positioning process in the said radiography apparatus

1 Radiography system
10 Y-axis rail
11 X-axis rail
12 Traveling cart
13 Tube elevator
14 Operation block
15 Telescopic mechanism
16 X-ray tube
19 Color touch panel
20 computers
21 First dial
22 Second dial
23 Handle
25 Rotation holding part
30 Control unit
31 X-axis control unit
32, 42, 52, 62, 72 AC servo amplifier
33, 43, 53, 63, 73 Servo motor
34, 44, 54, 64, 74, 91, 92 Potentiometer
35 X-axis operating force sensor
41 Y-axis control unit
45 Y-axis operation force sensor
50 X-ray generation circuit
51 Z-axis control unit
55 Z-axis operating force sensor
61 α-axis control unit
71 β-axis control unit
81, 82 LED unit
95 Bogie tilt sensor
96 Z-axis tilt sensor
97 tube switch
100 travel units
200 position
202, 303, 404 Radiation solid state detector
300 Standing stand
400 stand

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 and FIG. 2 are perspective views showing an overall configuration of a radiation imaging apparatus according to an embodiment of the present invention and a main part thereof, and FIG. 3 is a block diagram showing an electrical configuration of the radiation imaging apparatus. It is.

  As shown in FIG. 1, the radiation imaging apparatus 1 includes an overhead traveling unit 100, a recumbent photographing stand 200 for photographing a lying subject, and a stand for photographing a standing subject. It is composed of a position photographing stand 300.

  The overhead traveling unit 100 includes a pair of Y-axis rails 10 and 10 that are horizontally fixed to a hospital ceiling or the like so as to extend in one direction (Y direction), and a horizontal direction orthogonal to the Y-axis rails 10 and 10. A pair of X-axis rails 11, 11 extending in the direction (X direction), and traveling along these X-axis rails 11, 11 are attached to each X-axis rail 11 and attached to the Y-axis A driving carriage 12 is applied to a wheel (not shown) that engages with the rail 10, thereby causing the X-axis rails 11, 11 to travel along the Y-axis rails 10, 10, and extends downward from the traveling carriage 12. The tube elevating unit 13 attached in a state and an operation block 14 as a photographing element mounting unit attached near the lower end of the tube elevating unit 13 are configured.

  The tube lifting / lowering unit 13 includes an expansion / contraction mechanism 15 in which a plurality of cylindrical members having different sizes are coaxially combined, and the expansion / contraction length, that is, the length in the vertical direction by a drive mechanism disposed in the traveling carriage 12. Can be changed. In the present embodiment, this vertical direction is defined as the Z direction.

  A part of the surface of the expansion / contraction mechanism 15 is painted red in the vertical direction. On the other hand, the Y-axis rails 10 and 10 are painted yellow, and the X-axis rails 11 and 11 are painted green.

  The recumbent photographing table 200 includes a bed 201 and a radiation solid detector 202 arranged horizontally so that the radiation detection surface 202a faces upward below the bed 201. The radiation exposure axis direction of the radiation solid detector 202 arranged in this way, that is, the direction in which the normal G of the radiation detection surface 202a extends is the vertical direction (Z direction).

  On the other hand, the upright imaging table 300 includes a guide unit 301, a lifting table 302 that is movable in the vertical direction along the guide unit 301, and a radiation detection surface 303a in a horizontal direction inside the lifting table 302. And a radiation solid state detector 303 disposed therein. The radiation exposure axis direction of the radiation solid detector 303 arranged in this way, that is, the direction in which the normal H of the radiation detection surface 303a extends is the horizontal direction (Y direction).

  Next, the operation block 14 will be described in detail with reference to FIG. The operation block 14 is emitted from an X-ray tube 16 that emits X-rays as an example of radiation toward a subject, a tube holder 17 that holds the X-ray tube 16, and the X-ray tube 16. A collimator 18 for controlling the X-ray beam spreading direction and the like, a computer 20 having a color touch panel 19 as a display means and an input / output interface, and operations such as moving the operation block 14 and changing its direction. A handle 23 made of a rod-shaped member for performing the operation, and a disk-shaped first dial 21 and a second dial 22 attached to a part of the handle 23 with the long axis and the central axis aligned.

  The first dial 21 and the second dial 22 are movable parts of first and second operation parts that adjust the drive direction and drive amount of the drive part described later, respectively. They are arranged side by side in the direction of the central axis so that they can be rotated in reverse. In particular, in the present embodiment, the operation unit is configured such that both the dials 21 and 22 function as a fine adjustment dial for finely adjusting the driving amount.

  When the first dial 21 and the second dial 22 are arranged in this manner, as shown in FIGS. 4 and 5, when the operator rotates the handle 23 while holding the handle 23 with his / her hand, Naturally from the structure, the first dial 21 on the upper side extends the thumb P and moves the front peripheral surface portion (that is, the portion in which the arrow A direction in FIG. 4 is a tangential direction) in the left-right linear direction, while the lower side The second dial 22 located at the side moves the thumb P slightly and moves the peripheral surface portion on the side (that is, the portion where the arrow B direction in FIG. 5 is a tangential direction) in the front-rear linear direction. The arrow A direction and the arrow B direction are substantially perpendicular to each other.

  As shown in FIG. 1, the operation block 14 having the above-described configuration is attached to the lower end of the tube lifting / lowering unit 13 via a rotation holding unit 25. The rotation holding unit 25 holds the operation block 14 with respect to the tube raising / lowering unit 13 so as to be rotatable in the α direction and the β direction in FIG. Here, the β direction is a rotation direction centered on an axis extending in the Z direction, and the α direction is an axis extending in the horizontal direction (the direction depends on the rotation position of the operation block 14 in the β direction). The direction of rotation.

  Next, the electrical configuration of the radiation imaging apparatus 1 will be described with reference to FIG. In the traveling carriage 12 (see FIG. 1) described above, a servomotor 33 that drives the traveling carriage 12 along the X-axis rails 11 and 11 to drive forward and reverse rotation of wheels not shown in the figure, and an X-axis rail. Servo motor 43 for driving wheels 11 and 11 running along Y-axis rails 10 and 10 to drive forward and reverse rotation of a wheel (not shown), and servo motor 53 for moving up and down tube raising and lowering unit 13 by extending and retracting telescopic mechanism 15 The drive amount and drive direction of the servo motors 33, 43, 53 are respectively controlled by the X-axis control unit 31, the Y-axis control unit 41, and the Z-axis control via the AC servo amplifiers 32, 42, 52. Controlled by the unit 51. The operations of the control units 31, 41, 51 are controlled by the control unit 30 connected via the control wiring 60.

  In addition, there are provided potentiometers 34, 44, 54 for detecting the driving amount and driving direction of the servo motors 33, 43, 53, that is, the moving amount and moving direction of the operation block 14 in the X, Y, Z directions, respectively. Are input to the X-axis control unit 31, the Y-axis control unit 41, and the Z-axis control unit 51, and are also input to the control unit 30.

  In the present embodiment, the X-axis control unit 31, the AC servo amplifier 32, and the servo motor 33 constitute a first drive unit, and the Y-axis control unit 41, the AC servo amplifier 42, and the servo motor 43 constitute a second drive unit. The third drive unit is configured by the Z-axis control unit 51, the AC servo amplifier 52, and the servo motor 53.

  On the other hand, a servo motor 63 that rotates the operation block 14 in the α direction in FIG. 1 and a servo motor 73 that rotates the operation block 14 in the β direction in FIG. 1 are arranged in the operation block 14 (see FIG. 1). It is installed. The drive amounts and drive directions of the servo motors 63 and 73 are controlled by the α-axis control unit 61 and the β-axis control unit 71 via AC servo amplifiers 62 and 72, respectively. The operations of the control units 61 and 71 are controlled by the control unit 30 connected via the control wiring 60.

  Further, there are provided potentiometers 64 and 74 for detecting the drive amount and drive direction of the servo motors 63 and 73, that is, the rotation amount and the rotation direction of the operation block 14 in the α and β directions, respectively. The signals are input to the axis control unit 61 and the β-axis control unit 71 and also input to the control unit 30.

  The computer 20 (see FIG. 1) described above is connected to the control unit 30 via the control wiring 60. The computer 20 is connected to the color touch panel 19 shown in FIG. 1 and a speaker 29 with an amplifier for issuing various voice guidance and alarms.

  The operation block 14 is automatically moved as will be described later, and can be stopped at a desired position by the operator holding the handle 23 and moving it in the X, Y, and Z directions. The operation block 14 is provided with an X-axis operation force sensor 35, a Y-axis operation force sensor 45, and a Z-axis operation force sensor 55 that detect operation forces in the X, Y, and Z directions when moved in this manner. These detection outputs are input to motor speed information generation circuits 37, 47, 57 via variable LPFs (low pass filters) 36, 46, 56, respectively. The motor speed information generated by these motor speed information generation circuits 37, 47, 57 is input to the control unit 30 via the control wiring 60.

  An acceleration sensor 83 for detecting the acceleration applied when the operation block 14 is moved is attached to a part of the operation block 14, and the detection output thereof is input to the variable LPFs (low pass filters) 36, 46, 56. It is like that.

  The X-ray tube 16 shown in FIG. 1 is driven by an X-ray generator 50 to generate X-rays. The operations of the X-ray generator 50 and the collimator 18 (see FIG. 1) are controlled by the control unit 30 via the control wiring 60. Further, a tube switch 97 is connected to the control unit 30 through a control wiring 60, and a trigger signal for causing the X-ray tube 16 to emit light is input from the tube switch 97 to the X-ray generator 50.

  The operation block 14 is provided with potentiometers 91 and 92 for detecting the rotation amount and the rotation direction of the first dial 21 and the second dial 22, respectively, and their detection outputs are controlled via the control wiring 60, respectively. This is input to the part 30. In the present embodiment, the first dial 21, the potentiometer 91 and the control unit 30 constitute a first operation unit, and the second dial 22, the potentiometer 92 and the control unit 30 constitute a second operation unit.

  The first dial 21 and the second dial 22 are formed of, for example, a semi-transparent member, and an LED unit in which an LED (light emitting diode) that emits green light and an LED that emits red light are combined as an example. 81 and 82 are installed. These LED units 81 and 82 are controlled to be lit by the control unit 30 via the control wiring 60, and the LEDs to be lit are selected from the above, so that they can emit light in red, yellow, or green as a whole. It has become.

  Further, the traveling carriage 12 is attached with a carriage inclination sensor 95 which is a biaxial inclination sensor for detecting the inclination in the X direction (inclination in the XZ plane) and the inclination in the Y direction (inclination in the YZ plane). A Z-axis tilt sensor 96, which is a biaxial tilt sensor that detects the X-direction tilt and the Y-direction tilt of the long axis, is also installed near the lower end of the ball elevating unit 13, and the detection outputs of these sensors 95 and 96 are respectively The signal is input to the control unit 30 via the control wiring 60.

  Note that the control wiring 60 is connected to a main computer (not shown), and the main computer controls the overhead traveling unit 100 in conjunction with the upright photographing stand 200, the standing photographing stand 300, etc. Since the point is not directly related to the present invention, a detailed description is omitted.

  Hereinafter, the operation of the radiation imaging apparatus 1 of the present embodiment having the above-described configuration will be described. Basically, the radiation imaging apparatus 1 is configured to perform imaging using a supine imaging table 200 as shown in FIG. 6, imaging using a standing imaging table 300 as shown in FIG. 8, and imaging as shown in FIG. Any of the photographing using the standing position photographing stand 300 arranged in the opposite direction to the case of 8 can be performed.

  In the case shown in FIG. 6, the subject F is placed while lying on the bed 201, and the operation block 14 is arranged with the X-ray tube 16 (see FIG. 2) facing downward. By pushing the ball switch 97, the X-ray tube 16 is driven. Thereby, radiation emitted from the X-ray tube 16 and transmitted through the subject F is detected by the radiation solid detector 202, and a signal carrying transmission radiation image information of the subject F is obtained from the radiation solid detector 202. It is done.

  In the case shown in FIG. 8, the subject F is placed in a state of standing in front of the lifting platform 302, and the operation block 14 is placed in a state where the X-ray tube 16 (see FIG. 2) is turned sideways. The X-ray tube 16 is driven by pressing the tube switch 97 in this state. Thereby, the radiation emitted from the X-ray tube 16 and transmitted through the subject F is detected by the radiation solid detector 303, and a signal carrying the transmission radiation image information of the subject F is obtained from the radiation solid detector 303. It is done. The same applies to the case shown in FIG.

  When the state shown in FIG. 6 is changed to the state shown in FIG. 8, the operation block 14 is rotated in the α direction in FIG. 1 by manual operation performed by grasping the handle 23 or by driving the servo motor 63. At this time, since the postures of the first dial 21 and the second dial 22 change in conjunction with the rotation of the operation block 14, a linear direction (in the direction of arrow A in FIG. 4) for operating the first dial 21 and the second dial 22 The direction of the straight line (in the direction of arrow B in FIG. 5) is also changed.

  In performing radiography as described above, it is necessary to set the X-ray tube 16 at a predetermined position with respect to the radiation solid detector 202 or 303. Hereinafter, the movement of the X-ray tube 16 for that purpose will be described.

  The operation block 14 holding the X-ray tube 16 can be moved in the X, Y, and Z directions by driving the servo motors 33, 43, and 53. When moving the operation block 14 in such a manner, for example, stop position information of the X-ray tube 16 is input via the color touch panel 19, and the control unit 30 drives the servo motors 33, 43, 53 based on the information. The amount and the driving direction are determined, and information regarding the driving amount and the driving direction is input to the X-axis control unit 31, the Y-axis control unit 41, and the Z-axis control unit 51.

  The X-axis control unit 31, the Y-axis control unit 41, and the Z-axis control unit 51 control the drive amount and drive direction of the servo motors 33, 43, and 53 based on the input information. The X-ray tube 16 is set to a desired position in the X, Y, and Z directions. The X, Y, and Z direction positions of the X-ray tube 16 set in this way are detected by potentiometers 34, 44, and 54, and the detected position information is displayed on the color touch panel 19. Therefore, the operator can stop the X-ray tube 16 at a desired position while confirming this display.

  The movement mode of the X-ray tube 16 as described above is hereinafter referred to as “coarse movement mode”. Note that the position of the X-ray tube 16 is defined by, for example, two-dimensional coordinates with the center position of the radiation solid detector 202 or 303 arranged facing the X-ray tube 16 as the origin. Before the X-ray tube 16 is driven for radiography, a laser beam for position confirmation is emitted from the X-ray irradiation port or the collimator 18 and is emitted from the bed 201 of the irradiation position imaging table 200. Alternatively, the position of the X-ray tube 16 may be confirmed by irradiating the lifting platform 302 of the standing imaging table 300 and observing the irradiation position of the laser beam.

  The X-ray tube 16 can also be moved in a mode called “PA (power assist) mode”. The PA mode is a mode in which the operator moves the operation block 14 by manual operation while assisting the movement of the operation block 14 by the driving force of the servomotors 33, 43, and 53. That is, in this case, the operator holds the handle 23 (see FIG. 2) with one hand, and moves the operation block 14 in any direction in the X, Y, and Z directions, or in the synthesis direction thereof.

  At this time, the X-axis operating force sensor 35, the Y-axis operating force sensor 45, and the Z-axis operating force sensor 55 shown in FIG. 3 detect the directions and magnitudes of the operating forces in the X, Y, and Z directions, respectively. The detection outputs are input to motor speed information generation circuits 37, 47, and 57 through variable LPFs 36, 46, and 56, respectively. The motor speed information generating circuits 37, 47 and 57 basically issue motor speed information for instructing higher speed as the operating force is larger. The control unit 30 receives this motor speed information, and sends an instruction signal for rotating the servo motors 33, 43, 53 in the rotation direction corresponding to the speed and the rotation direction corresponding to the direction of the operation force. 31, input to the Y-axis control unit 41 and the Z-axis control unit 51.

  When the operator confirms that the X-ray tube 16 has reached the desired position by the above operation in the same manner as in the coarse motion mode described above, the operator stops the operation of moving the operation block 14. Then, the motor speed information generated by the motor speed information generating circuits 37, 47, 57 indicates the speed 0 “zero”, and the operation block 14 stops. Note that the acceleration sensor 83 shown in FIG. 3 detects the acceleration of the operation block 14 that is manually moved, and the characteristics of the variable LPFs 36, 46, and 56 can be changed according to the detected acceleration. .

  It is quite difficult to accurately stop the X-ray tube 16 at a desired position with respect to the radiation solid state detector 202 or 303 only by the operation in the coarse motion mode or PA mode described above. Positioning errors often occur. For example, in the diagnosis of cancer tumors, the tumor size after a certain period of time is an important index, and therefore, the change in tumor size is observed by superimposing the images before and after the period. . In that case, if the actual irradiation position is shifted by about 2 mm from the radiation irradiation position intended by the engineer, the imaging position is shifted between the two images, and accurate tumor size comparison becomes impossible.

  Therefore, in this apparatus, the “fine adjustment mode” that can position the X-ray tube 16 with higher accuracy can be executed. Hereinafter, this fine adjustment mode will be described. FIG. 16 shows the flow of processing instructed by the control unit 30 when entering the fine adjustment mode. First, when the process starts in step S1, the X-ray tube 16 is positioned in the coarse motion mode or the PA mode described above in step S2.

  Then, in step S3, the rotation angles of the first dial 21 and the second dial 22 are measured by the potentiometers 91 and 92. Next, in step S4, it is determined by the measurement whether one of the dials is rotating. When it is determined that neither dial 21 or 22 is rotating, the flow of processing returns to step S3 and the same processing is repeated.

  If it is determined in step S4 that one of the dials is rotating, that is, the operator is in the fine adjustment mode, then in step S5, the coarse motion mode or PA mode processing that has been performed is performed. In addition to being prohibited, the control unit 30 is prohibited from accepting an operation input from the other dial, that is, an output signal from the potentiometer 91 or 92.

  In step S6, the servo motor 33, 43 or 53 is rotated at a relatively low speed in accordance with the rotation of the rotating dial 21 or 22. At this time, the rotation direction and the rotation speed (rotation amount) of the dial 21 or 22 are detected by the potentiometers 91 or 92, respectively, and the forward / reverse rotation direction of the servo motor 33, 43 or 53, that is, X, according to the detected rotation direction. The direction of movement of the tube 16 is determined, and the number of rotations of the servomotor 33, 43 or 53, that is, the amount of movement of the X-ray tube 16 is determined in proportion to the detected number of rotations.

  When the servo motor 33, 43 or 53 is thus rotated, the operation block 14 moves at a very low speed, so that the operator can stop the X-ray tube 16 at a desired position with high accuracy. The correspondence between the dial 21 or 22 operated at this time and the servomotors 33, 43 or 53 to be driven will be described in detail later.

  Next, in step S7, it is determined whether or not the one dial 21 or 22 continues to rotate. If the rotation continues, the process flow returns to step S6 and the same process is repeated.

  If it is determined in step S7 that the rotation of the one dial 21 or 22 has stopped, that is, the fine adjustment by the dial has already been completed, then in step S8, a predetermined time has elapsed since the detection of the rotation stop. It is determined whether or not. If the predetermined time has not elapsed, the processing flow returns to step S6. At this time, however, the one dial 21 or 22 has already stopped, so that the rotation of the motor is not commanded.

  If it is determined in step S8 that the predetermined time has elapsed, then in step S9, it is determined whether or not the flow of processing has come to this step for the first time. If it is determined to be the first time, then in step S10, input from the one dial 21 or 22 that has been operated so far is prohibited, and switching is made to accept input from the other dial 22 or 21. Is made.

  Next, the process flow returns to step S3, and the operation block 14, that is, the X-ray tube 16 is moved at a slow speed in the same manner as described above by rotating the other dial 22 or 21. Note that the second movement of the X-ray tube 16 is different in direction from the first movement of the X-ray tube 16 for reasons described later.

  In this way, when the X-ray tube 16 is moved at a very low speed for the second time and stopped at a desired position, the flow of processing has come to this step in step S9 in the same manner as the previous time. It is determined whether or not. Since this is not the first time, the process moves to step S11, where the series of processes ends.

  Next, the correspondence between the operated dial 21 or 22 and the driven servomotor 33, 43 or 53 will be described. In this example, as shown in FIG. 6, photographing using the standing photographing table 200 and photographing using the standing photographing table 300 as shown in FIG. 8 are selectively performed. In the state of FIG. 6, the rotation holding unit 25 holds the operation block 14 in the direction in which the direction of the radiation irradiation axis R of the X-ray tube 16 is the Z direction, and in the state of FIG. The operation block 14 is held in such a direction that the direction of the irradiation axis R is the Y direction. Here, the rotation position of the operation block 14 in the former case is defined as a first rotation position, and the rotation position of the operation block 14 in the latter case is defined as a second rotation position.

  Whether the operation block 14 is in the first rotational position or the second rotational position is detected by a potentiometer 64 as rotational position detecting means shown in FIG. At this time, the determination of the first rotation position and the second rotation position may be performed under the following conditions after defining the rotation angle of the radiation irradiation axis R of the X-ray tube 16 as shown in FIG.

(1) If this rotation angle is in the range of −90 ° to 90 ° in the initial state, the first rotation position is set.

(2) If the rotation angle is −90 °, which is larger than the absolute value by 90 °, the second rotation position is set.

(3) If the rotation angle has passed 0 °, it is determined that the rotation position has returned from the second rotation position to the first rotation position.

  The potentiometer 64 inputs a signal indicating the rotational position to the control unit 30 via the control wiring 60. Note that the operation block 14 can be set to the respective rotational positions by the operator manually grasping the handle 23 and set to the respective rotational positions by driving the servo motor 63 shown in FIG. You can also.

  When the signal indicating the first rotational position is input from the potentiometer 64, the control unit 30 is based on the detection output of the potentiometer 91 that detects the rotation of the first dial 21, and the Y-direction moving servo motor 43 (FIG. 3) and the X-direction moving servo motor 33 (see FIG. 3) is driven based on the detection output of the potentiometer 92 that detects the rotation of the second dial 22. Therefore, as shown in FIG. 7, when the first dial 21 is operated substantially in the Y direction (the A direction described with reference to FIG. 4), the operation block 14, that is, the X-ray tube 16 is moved in substantially the same Y direction. To move. Further, when the second dial 22 is operated substantially in the X direction (the B direction described with reference to FIG. 5), the operation block 14, that is, the X-ray tube 16 moves in the X direction substantially the same as that direction.

  On the other hand, when a signal indicating the second rotational position is input from the potentiometer 64, the control unit 30 is based on the detection output of the potentiometer 91 that detects the rotation of the first dial 21, and the Z-direction moving servo motor 53 ( 3) is driven, and the X-direction moving servo motor 33 (FIG. 3) is driven based on the detection output of the potentiometer 92 that detects the rotation of the second dial 22. Therefore, as shown in FIG. 9, when the first dial 21 is operated substantially in the Z direction, the operation block 14, that is, the X-ray tube 16, moves in the Z direction substantially the same as that direction. When the second dial 22 is operated in the X direction, the operation block 14, that is, the X-ray tube 16, moves in the X direction substantially the same as that direction.

  As described above, if the operation direction of the first dial 21 and the second dial 22 and the movement direction of the X-ray tube 16 substantially coincide with each other, the operator makes a mistake in the direction in which the X-ray tube 16 is moved. In addition, the X-ray tube 16 can be quickly moved in this fine adjustment mode.

  Further, in the present embodiment, when the signal indicating the first rotational position is input from the potentiometer 64, the control unit 30 causes the LED unit 81 disposed in the first dial 21 to emit light yellow as a whole. The LED unit 82 disposed in the second dial 22 is entirely made to emit green light. As described above, the Y-axis rails 10 and 10 are painted yellow, and the X-axis rails 11 and 11 are painted green. The operator operates the first dial 21 by comparing these colors. Then, the X-ray tube 16 can be moved in the Y direction in which the Y-axis rails 10 and 10 extend. If the second dial 22 is operated, the X-ray tube 16 is moved in the X direction in which the X-axis rails 11 and 11 extend. It can be moved and intuitively understood.

  Instead of displaying the first dial 21 and the second dial 22 in different colors as described above, a character display device such as a liquid crystal display device is arranged corresponding to each dial, and according to the function switching of each dial. For example, characters such as “for movement in the Y direction” and “for movement in the X direction” may be displayed.

  In addition, when the signal indicating the second rotational position is input from the potentiometer 64, the control unit 30 causes the LED unit 81 disposed in the first dial 21 to emit light in red as a whole, and the second dial. The LED unit 82 disposed in 22 is made to emit green light as a whole. As mentioned earlier, part of the surface of the telescopic mechanism 15 is painted red in the vertical direction, and the X-axis rails 11 and 11 are painted green, so the operator should compare these colors. Thus, if the first dial 21 is operated, the X-ray tube 16 can be moved in the Z direction in which the telescopic mechanism 15 extends, and if the second dial 22 is operated, the X-ray tube 16 is moved to the X-axis rails 11, 11. It can be intuitively understood that it can be moved in the X direction in which is extended.

  Further, as described above, even if there are three directions in which the X-ray tube 16 is moved in total, only two dials 21 and 22 respectively corresponding to the two directions that need to be moved in each imaging method are provided. If it is provided, it is possible to prevent the occurrence of problems such as an erroneous operation due to the presence of an extra interface and a troublesome operation. This can be said to be a very beneficial effect when it is required to perform radiography quickly and appropriately, for example, when radiographs of emergency patients are taken.

  FIG. 15 shows a preferred example of the relationship between the rotational speeds of the dials 21 and 22 and the movement amount of the X-ray tube 16 in the fine adjustment mode. In the field of radiography, there is a demand for precise positioning within 2 seconds within an error of 2 mm. Since the speed at which a human rotates the dial is approximately 1 rotation / second, it is desirable that the amount of movement of the X-ray tube 16 be approximately 2 mm when the dials 21 and 22 are rotated once (360 °). This relationship is obtained by adjusting the gain when a predetermined gain is given to the angle detection signals of the potentiometers 91 and 92 to determine the number of rotations of the servo motors 33, 43 and 53 for moving the X-ray tube. It is possible to obtain a relationship that provides a comfortable feeling of operation.

  According to the radiation imaging apparatus 1 of this embodiment, the X-ray tube 16 can be positioned with respect to the radiation solid detector 202 or 303 with an accuracy of less than 2 mm by using the “fine adjustment mode”. it can. In the diagnosis of tumors such as cancer, confirmation of tumor size is an important point of diagnosis. Although the level of precision positioning with the conventional power assist is about 2 mm, as described above, the radiographic apparatus 1 can achieve positioning with higher accuracy than that. Since a radiographic apparatus is a highly anticipated device for diagnosing minute tumors of 2 mm or less that are difficult to visually recognize, the clinical significance of being able to irradiate a precise position with radiation is great.

  Next, a case where shooting is performed as shown in FIGS. 6 and 10 will be described. That is, in this case, the rotation position of the operation block 14 in the state of FIG. 6 is the first rotation position, and the rotation position of the operation block 14 in the state of FIG. 10 is the second rotation position.

  In this example, the functions given to the first dial 21 and the second dial 22 in the state of FIG. 6 may be the same as those described above. When radiography is performed as shown in FIG. 10, the first dial 21 and the second dial 22 are operated as shown in FIG. 11, which is the same as that shown in FIG. Therefore, when shooting is performed as shown in FIG. 10, the correspondence between the dial 21 or 22 to be operated and the servomotors 33, 43, or 53 to be driven may be the same as in the case of shooting as shown in FIG. .

  Next, a case where shooting is performed as shown in FIGS. 6 and 12 will be described. In this case, the rotation position of the operation block 14 in the state of FIG. 6 is defined as a first rotation position, and the rotation position of the operation block 14 in the state of FIG. 12 is defined as a second rotation position. In the state shown in FIG. 12, the imaging table 400 holding the radiation solid detector 404 is used obliquely, and the operation block 14 is rotated at a rotation position (second position) where the radiation irradiation axis R faces the intermediate direction between the Y direction and the Z direction. Rotation position).

  Also in this example, the functions given to the first dial 21 and the second dial 22 in the state of FIG. 6 may be the same as those described above. On the other hand, when radiography is performed as shown in FIG. 12, the first dial 21 and the second dial 22 are operated as shown in FIG. 13. At this time, the operation block 14, that is, the X-ray tube 16 is moved. There are generally two types. One is moved in two of the X, Y, and Z directions, and the other is moved along the radiation solid detector 404, that is, the X direction and the YZ direction (Y direction and Z direction). In-plane direction including).

First, the former case will be described. At this time, since the X-ray tube 16 is moved in two orthogonal directions, the correspondence between the operated dial 21 or 22 and the driven servo motor 33, 43 or 53 is as follows: For example, it may be the same as in FIG. Next, the latter case will be described. At this time, if the angle formed between the direction of the radiation irradiation axis R of the X-ray tube 16 and the Z direction is θ and the input values from the first dial 21 and the second dial 22 are D1 and D2, respectively, the X movement amount , Y movement amount and Z movement amount are given by the following equations.

  That is, at this time, since the Y movement amount corresponding to the value obtained by multiplying the input value D1 by the first dial 21 by cos θ and the Z movement amount corresponding to the value obtained by multiplying the input value D1 by sin θ, these movement amounts are obtained. Are driven, the Y movement servomotor 43 and the Z movement servomotor 53 of FIG. 3 are driven. Further, in the X direction, the X movement amount corresponding to the input value D2 by the second dial 22 is obtained, and the X movement servomotor 33 in FIG. 3 is driven so as to obtain the movement amount. As a result, the X-ray tube 16 moves in the X direction and the YZ direction along the radiation solid detector 404.

  As described above, the embodiment having the configuration in which the X-ray tube 16 is mounted on the operation block 14 which is the imaging element mounting unit has been described. However, the present invention mounts radiation detection means such as a radiation solid detector on the imaging element mounting unit. Thus, the present invention can also be applied to a radiation imaging apparatus having a configuration for moving the radiation detection means. For example, in the case where the radiation solid detector 202 shown in FIG. 1 is mounted on the imaging element mounting portion, the radiation solid instead of the direction of the X-ray tube 16 being defined by the direction of the radiation irradiation axis R in the above embodiment. The direction of the detector 202 may be defined by the direction of the detection surface normal line G.

  Further, the radiation detection means is not limited to the radiation solid detector, and the present invention can also be applied to a radiation imaging apparatus including the above-described stimulable phosphor sheet or silver salt X-ray film as the radiation detection means.

  Further, the guide mechanism and the drive unit are not limited to the ceiling-suspended type in the above-described embodiment, and it is of course possible to apply, for example, a robot arm or the like installed on the floor.

  Furthermore, as an operation unit for adjusting the drive direction and drive amount of the drive unit such as the servo motors 33, 43, and 53 described above, in addition to the above-described disk-shaped dials 21 and 22 as movable units, a joystick or a mouse Further, it is possible to use a ball roller or the like. However, the structure having the disk-shaped dials 21 and 22 as movable parts as described above is simple in structure, and even if both of them have the same configuration, the operation direction is combined with the structure of a human hand. Since it can be changed between the two, it is particularly suitable for the radiation imaging apparatus of the present invention.

  In addition, the dials 21 and 22 as described above have finer resolution than other input means and can reflect the subtle input of the operator in positioning, so that they can be used for positioning with high accuracy and good reproducibility in a short time. Thus, efficient shooting is realized. For example, assume that the time required for positioning can be reduced by 20 seconds per subject. In Japan, the frequency of shooting is high, and it is often the case that about 100 people take images a day. In that case, the engineer's working hours can be shortened by about 2000 seconds ≒ 33 minutes per day, and the economic effect is very large.

  Also, in the situation of emergency operation after being brought into a hospital due to an accident, being able to reduce the time by 20 seconds is very effective in protecting the patient's life. That is, to give a specific example, when the brain falls into anoxic state for 240 seconds after cardiac arrest, it often suffers irreversible damage, but the time of 20 seconds corresponds to 8% thereof.

  Furthermore, since the sense of precise positioning by rotation is familiar to many engineers, the use of this kind of disc-shaped dials 21 and 22 also has the effect of being able to master the operation in a shorter period of time. .

Claims (16)

A radiation source that emits radiation toward the subject;
Radiation detecting means for detecting radiation transmitted through the subject;
An imaging element mounting portion on which the radiation detection means or the radiation source is mounted;
A guide mechanism that holds the photographing element mounting portion so as to be movable in X, Y, and Z directions orthogonal to each other;
First, second, and third drive units that individually move the imaging element mounting unit along the guide mechanism in each of the X, Y, and Z directions;
In the radiation imaging apparatus comprising rotation holding means that can switch and set the imaging element mounting portion held by the guide mechanism to a plurality of rotation positions so as to change the radiation exposure axis direction,
First and second operation units, each of which adjusts the driving direction and driving amount of one or two of the first to third driving units;
Rotational position detecting means for detecting the rotational position of the imaging element mounting unit;
In accordance with the rotational position detected by the rotational position detecting means, the first and second operation units, among the first to third drive units, each have an operation target drive unit that adjusts the drive direction and the drive amount. A radiation imaging apparatus comprising a control means for selecting. The rotation holding means sets the imaging element mounting portion to the Z direction as a vertical direction, a first rotation position where the radiation exposure axis direction is the Z direction, and a second rotation where the radiation exposure axis direction is the Y direction. To set the position,
When the control unit detects the first rotation position by the rotation position detection unit, one of the first and second drive units as each operation target drive unit of the first and second operation units, When the other rotation position is selected and the second rotation position is detected by the rotation position detection means, one of the first and third drive units as each operation target drive unit of the first and second operation units, The radiation imaging apparatus according to claim 1, wherein the other is selected. The rotation holding means sets the imaging element mounting portion as the Z direction as a vertical direction, a first rotation position where the radiation exposure axis direction is the Z direction, and the radiation exposure axis direction is intermediate between the Y direction and the Z direction. Is set to the second rotation position that is the direction,
When the control unit detects the first rotation position by the rotation position detection unit, one of the first and second drive units as each operation target drive unit of the first and second operation units, When the other is selected and the second rotational position is detected by the rotational position detecting means, the first drive unit, the second and the third are used as the operation target drive units of the first and second operation units. The radiation imaging apparatus according to claim 1, wherein one of the driving units is selected. As said 1st, 2nd operation part, what has each a movable part which moves to a linear direction at least in part is used,
These movable parts are configured to change the orientation in the linear direction by changing the posture in conjunction with the rotation of the imaging element mounting part,
When the imaging element mounting unit is in each of the first rotation position and the second rotation position, the linear direction of the movement of the movable unit of the first and second operation units is determined by the operation target drive unit of each operation unit. The radiation imaging apparatus according to claim 2, wherein the movable part is disposed so as to be aligned with a moving direction of the imaging element mounting part.   The radiation imaging apparatus according to claim 4, wherein the first and second operation units are configured to change a drive direction of the operation target drive unit in accordance with a direction of movement of the movable unit. .   6. The radiation imaging apparatus according to claim 4, wherein each movable part of the first and second operation parts is made of a disk-like member that rotates about a central axis.   7. The radiation according to claim 6, wherein the movable parts made of the disk-shaped members of the first and second operation parts are arranged side by side in the direction of the central axis with the central axes aligned. Shooting device.   8. The radiation according to claim 7, wherein the movable portion is attached to a rod-shaped portion constituting a handle integrated with the imaging element mounting portion so that a long axis and a central axis of the rod-shaped portion are aligned. Shooting device.   Corresponding to the respective movable parts of the first and second operation parts, the moving direction of the imaging element mounting part moved by the operation target drive part of each operation part is changed according to the rotation position switching of the imaging element mounting part. The radiation imaging apparatus according to claim 1, further comprising display means for switching display.   The radiation imaging apparatus according to claim 9, wherein the display means indicates a moving direction of the imaging element mounting unit with characters.   The radiation imaging apparatus according to claim 9, wherein the display unit indicates a moving direction of the imaging element mounting unit with a unique color determined according to the moving direction.   12. A moving direction guide display is provided in the vicinity of the guide mechanism, which indicates a moving direction of the photographing element mounting portion corresponding to each of the unique colors in the same color as that color. Radiography equipment.   When the control means stops the function of the other operation unit when one of the first and second operation units is being operated, and detects that the operation of the one operation unit is completed, the other operation The radiation imaging apparatus according to claim 1, wherein the radiation imaging apparatus is configured to restore the function of the unit.   The control means detects that the operation of one of the first and second operation units is completed when a predetermined time elapses after the operation is stopped. 13. The radiographic apparatus according to 13. The imaging element mounting unit is mounted with the radiation source,
The radiation imaging apparatus according to claim 1, wherein an irradiation axis direction of the radiation source is changed by changing a rotation position of the imaging element mounting unit. The imaging element mounting unit is mounted with the radiation detection means,
15. The detection surface normal direction of the radiation detection means, which is the radiation exposure axis direction, is changed by changing the rotational position of the imaging element mounting portion. The radiation imaging apparatus of any one of Claims.

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