JP5880285B2 - Radiography equipment - Google Patents

Description

  The present invention relates to a radiation imaging apparatus including a radiation generator, a radiation detection unit that detects radiation emitted from the radiation generator and passed through a subject, and a bucky mechanism that swings a scattered radiation removal grid. As this radiation, for example, X-rays are used.

  The scattered radiation removal grid used in such an X-ray imaging apparatus as a radiation imaging apparatus is for improving the contrast of an image captured by removing scattered X-rays during X-ray imaging. An X-ray absorbing member such as foil and an X-ray transmissive intermediate member such as aluminum are alternately arranged. When X-ray imaging is performed using this scattered radiation removal grid, the scattered radiation removal grid is reciprocated in a direction orthogonal to the fringes in order to prevent the grid of the grid from appearing in stripes in the X-ray image. A bucky mechanism that performs X-ray imaging by irradiating X-rays in a moved (swinged) state is employed.

  However, the scatter removal grid is not always used. Since this scattered radiation removal grid absorbs part of the X-rays, for example, when performing imaging by automatic exposure control using a phototimer, the exposure X-ray dose to the subject is increased. For this reason, when imaging a child whose X-ray exposure is particularly desired to be reduced, gridless imaging in which X-ray imaging is performed with the scattered radiation removal grid removed may be performed. In addition, since the focusing grid of the scattered radiation removal grid has a focusing distance suitable for imaging, the focusing grid may be replaced with one having an appropriate focusing distance according to the imaging distance. Furthermore, the scattered radiation removal effect may be adjusted by changing the grid ratio or grid density of the scattered radiation removal grid. For this reason, in the Bucky mechanism, it is necessary to make the scattered radiation removal grid detachable.

  In Patent Document 1, a convex part in which a long hole extending in the vertical direction is formed in the upper center of the grid is provided, and a crank pin connected to the long hole of the convex part in an eccentric state with respect to the rotation shaft of the motor is provided. An apparatus for processing radiation image information is disclosed in which a grid is reciprocated through a crankpin by engaging and rotating a rotating shaft of a pulse motor.

  Patent Document 2 includes an improper timing in an X-ray imaging apparatus that includes a lock mechanism that restricts the operation of attaching and detaching the grid unit, and a sensor group that monitors the operation of the lock mechanism. An X-ray imaging apparatus that prohibits the grid attachment / detachment operation is disclosed.

  In Patent Document 3, the grid unit is provided with a locking unit that locks the grid so as not to move with respect to the housing, and the photographing apparatus body has a release unit that acts on the locking unit to release the locked state. There is disclosed an X-ray imaging apparatus that is provided and enables safe attachment / detachment of a grid and stable driving of the grid.

JP 2003-334182 A JP 2003-250797 A JP 2001-333895 A

  By the way, in such a bucky mechanism, the swinging operation of the scattered radiation removal grid is started before the X-ray irradiation is started, and the swinging operation of the scattered radiation removal grid is stopped when the X-ray irradiation is completed. For this reason, the stop position of the scattered radiation removal grid when the swinging operation ends is different depending on the imaging time. Accordingly, when performing the attachment / detachment work of the scattered radiation removal grid, the operator may feel uncomfortable with the operation due to the difference in the amount of insertion and attachment position of the scattered radiation removal grid. Further, when the scattered radiation removal grid stops at a position far from the vicinity of the entrance, there is a problem that it is difficult to take out the scattered radiation removal grid.

  Further, in such a bucky mechanism, generally, as described in Patent Document 1 described above, the scattered radiation removing grid is formed by a crank slider mechanism using a crank pin and a slider that are rotated by driving a motor. The same operation is realized. When the scattered radiation removal grid is fixed to the bucky mechanism, a spring that urges the scattered radiation removal grid inserted from the entrance in the direction of the entrance is provided, and the scattered radiation that is about to jump out of the entrance by the action of the spring. The structure which fixes a removal grid with a fixed nail | claw is employ | adopted. When the scattered radiation removal grid is taken out from the bucky mechanism, the fixed claw is moved to an extraction position separated from the scattered radiation removal grid by pressing the movement mechanism of the fixed claw via an extraction button arranged near the entrance. I am letting. In such a case, if the scattered radiation removal grid stops at a position far from the vicinity of the entrance, the fixed claw moving mechanism cannot be pressed even if the extraction button is pressed, and the fixed claw is moved to the extraction position. It may not be possible.

  Further, when the crank arm in the crank slider mechanism is not at the dead point, that is, when the posture of the crank is not the posture corresponding to the position of the both ends of the swing of the scattered radiation removal grid, the extraction button is pressed. However, the moving mechanism of the fixed claw may move with the scattered radiation removal grid and the like, and the fixed claw may not be moved to the removal position. In such a case, it is possible to limit the movement of the fixed claw moving mechanism and the scattered radiation removal grid by adopting a configuration such as disposing a speed reducer between the motor and the crankpin. The apparatus becomes large and becomes an obstacle to X-ray imaging work.

  For this reason, it is preferable that the grid attachment / detachment position for attaching / detaching the scattered radiation removal grid is a position where the scattered radiation removal grid is closest to the entrance.

  On the other hand, in the Bucky mechanism, when preparation for X-ray imaging is completed, the scattered radiation removal grid starts to swing, and when the speed of the scattered radiation removal grid reaches the maximum, the Bucky mechanism gives an X-ray imaging permission signal. Sent. Therefore, in order to generate an X-ray imaging permission signal in as short a time as possible after preparation for X-ray imaging is completed, the scattered radiation removal grid is made to wait at a standby position that is optimal for acceleration of the scattered radiation removal grid. It is preferable to keep it. However, since this standby position is different from the grid attachment / detachment position described above, it takes a long time from when preparation for X-ray imaging is completed until the speed of the scattered radiation removal grid becomes maximum and X-ray imaging starts. There is a problem that is necessary.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide a radiation imaging apparatus capable of quickly performing radiation imaging after preparation for radiation imaging is completed. The present invention also provides a radiation imaging apparatus capable of quickly performing radiation imaging without installing a new signal line, even when an apparatus for attaching / detaching a scattered radiation removal grid is added to an existing radiation imaging apparatus. The second object is to provide the above.

The invention described in claim 1 includes a radiation generation source, a radiation detection unit that detects radiation irradiated from the radiation generation source and passed through the subject, and a bucky mechanism that swings the scattered radiation removal grid. In the radiation imaging apparatus, the scattered radiation removal grid is disposed in the Bucky mechanism and is driven by a motor to swing in a reciprocating path including a standby position suitable for acceleration of the scattered radiation removal grid. A swing mechanism for disposing the scattered radiation removal grid at a grid attachment / detachment position for attaching / detaching the bucky part, a first operation part for preparing for radiation irradiation, and for irradiating radiation from a radiation source A high voltage device for applying power to the radiation generation source, and when the first operation unit is operated, The line-grid, characterized in that a grid moving means for moving said standby position from said grid detaching position.

  The invention described in claim 2 is the grid attachment / detachment position in the invention described in claim 1, wherein the scattered radiation removal grid created when the first operation unit is operated to prepare for radiation irradiation is arranged in the grid attachment / detachment position. A grid standby position movement signal for moving from the standby position to the standby position, and a swing operation of the scattered radiation removal grid created when the second operation unit is operated to irradiate radiation A grid movement signal is generated by superimposing the swing operation start signal, and the grid movement signal is transmitted to a signal line extending from the high voltage device to the bucky mechanism.

  According to a third aspect of the present invention, in the second aspect of the present invention, the first switch that closes when the second operation unit is operated is connected to the signal line, and the first operation unit is operated. A second switch that closes when connected is connected to the signal line in parallel with the first switch via a capacitor.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the swing mechanism is connected to a crankshaft that rotates by driving the motor, and the crankshaft is centered on the crankshaft. A slider that rotates and has a crank arm provided with a crankpin, a long hole that engages with the crankpin, and a slider that is connected to a grid support that supports a scattered radiation removal grid inserted from a grid insertion port And a crank slider mechanism that reciprocates the grid support portion in a direction intersecting a long hole in the slider by rotating the crank arm around the crankshaft, The crank pin is a position closest to the grid insertion port.

  According to the first aspect of the present invention, since the scattered radiation removal grid is moved from the grid attachment / detachment position to the standby position when the first operation unit is operated, the scattered radiation removal grid is disposed at the standby position after completion of preparation for radiation imaging. The scattered radiation removal grid can be accelerated quickly to perform radiography rapidly.

  According to the second aspect of the present invention, the standby position movement signal and the swing operation start signal can be superimposed and transmitted via a single signal line. For this reason, even when a device for attaching / detaching a scattered radiation removal grid is added to an existing radiation imaging apparatus, it is not necessary to install a new signal line to move the scattered radiation removal grid, and the configuration is simplified. It becomes possible.

  According to the third aspect of the present invention, it is possible to create a standby position movement signal by the action of the capacitor and superimpose it on the swing operation start signal. For this reason, it is possible to transmit the grid movement signal with a simple configuration.

  According to the fourth aspect of the present invention, the scattered radiation removal grid arranged at the grid attaching / detaching position by the crank slider mechanism can be moved to the standby position by the grid moving means.

1 is a schematic diagram of an X-ray imaging apparatus as a radiation imaging apparatus according to the present invention. 3 is a schematic diagram of a hand switch 80. FIG. It is a block diagram which shows the control system of the X-ray imaging apparatus as a radiography apparatus concerning this invention. 2 is a schematic plan view of the bucky mechanism 1. FIG. FIG. 4 is an enlarged view of the vicinity of a grid fixing mechanism in the bucky mechanism 1. FIG. 4 is an enlarged view of the vicinity of a grid fixing mechanism in the bucky mechanism 1. 4 is an enlarged view of the vicinity of a crank slider mechanism in the bucky mechanism 1. FIG. 4 is an enlarged view of the vicinity of a crank slider mechanism in the bucky mechanism 1. FIG. 4 is an enlarged view of the vicinity of a crank slider mechanism in the bucky mechanism 1. FIG. It is a schematic diagram which shows a grid movement signal superimposing means. It is a time chart which shows X-ray imaging operation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of an X-ray imaging apparatus as a radiation imaging apparatus according to the present invention.

  The X-ray imaging apparatus according to the present invention includes a table-type X-ray imaging table 2 for imaging a subject on the top board 11 in a lying position, and a stand-type X-ray for imaging the subject in a standing position. An imaging table 3, an X-ray irradiation unit 4, and a high voltage device 5 for an operator to perform an X-ray imaging operation are provided. The table type X-ray imaging table 2 and the stand type X-ray imaging table 3 are each provided with a bucky mechanism 1. The table-type X-ray imaging table 2, the stand-type X-ray imaging table 3, and the X-ray irradiation unit 4 are installed in an imaging room for performing imaging on a subject. The high voltage device 5 is installed in an operation room for an operator to perform an X-ray imaging operation. The photographing room and the operation room are blocked by a partition wall 22.

  The table-type X-ray imaging table 2 includes a top plate 11 for placing the subject in a lying position, a bucky mechanism 1, and a moving mechanism 12 for moving the top plate 11 and the bucky mechanism 1. Is provided. On the other hand, the stand-type X-ray imaging table 3 includes a bucky mechanism 1 similar to the table-type X-ray imaging table 2, and an elevating member 23 that lifts and lowers the bucky mechanism 1 according to the height and imaging region of the subject. Is provided. Note that an X-ray detector such as a flat panel detector or a cassette containing an X-ray film is disposed as a radiation detection unit inside these Bucky mechanisms 1.

  The X-ray irradiation unit 4 includes an X-ray tube 15 as a radiation generation source, a collimator 16, and an operation handle 17. These X-ray tube 15, collimator 16, and operation handle 17 can be moved horizontally in the X, Y, and Z directions by an arm 14 that hangs down from a support portion 13 fixed to the ceiling, and have a horizontal axis and a vertical axis. It is rotatably supported at the center. Therefore, the X-ray tube 15 and the collimator 16 can be disposed opposite to both the table-type X-ray imaging table 2 and the stand-type X-ray imaging table 3.

  On the other hand, the high voltage device 5 installed in the operation room includes an operation panel 18 having a liquid crystal display unit 19, a plurality of operation switches 21, and an indicator 84 indicating that the X-ray tube 15 is ready for imaging, And a hand switch 80 having a two-stage push button.

  FIG. 2 is a schematic diagram of the hand switch 80.

  The hand switch 80 includes a grip portion 83 that is gripped by an operator, and a first operation button 81 and a second operation button 82 that are disposed at one end of the grip portion 83. These first and second operation buttons 81 and 82 are buttons that can be pressed continuously in two stages. When the first operation button 81 is pressed, an X-ray irradiation preparation start signal is transmitted from the high voltage device 5 to the X-ray tube 15 and the second operation button 82 is pressed, as will be described later. Then, a swaying operation start signal of the scattered radiation removal grid is transmitted from the high voltage device 5 to the bucky mechanism 1. The X-ray tube 15 emits X-rays when the speed of the scattered radiation removal grid becomes maximum in the bucky mechanism 1.

  FIG. 3 is a block diagram showing a control system of an X-ray imaging apparatus as a radiation imaging apparatus according to the present invention. In FIG. 3, only one of the bucky mechanisms 1 provided on the table type X-ray imaging table 2 and the stand type X-ray imaging table 3 is shown as a representative. The device 5 is also connected to another bucky mechanism 1, and these pair of bucky mechanisms 1 are selectively used.

  The bucky mechanism 1, the high voltage device 5, and the X-ray tube 15 are each provided with control units 95, 96, and 97 having a CPU and the like, and their operations are controlled by these control units 95, 96, and 97. The The bucky mechanism 1 and the high voltage device 5 are connected by a signal line 91 and a signal line 92, and the high voltage device 5 and the X-ray tube 15 are connected by a signal line 93. The bucky mechanism 1 is provided with a stepping motor 40 for swinging the scattered radiation removal grid, as will be described later. The rotation of the stepping motor 40 is controlled by the control unit 95 of the bucky mechanism 1.

  In such an X-ray imaging apparatus, the scattered radiation removal grid is housed in the Bucky mechanism 1 to perform X-ray imaging, and the scattered radiation removal grid is removed from the Bucky mechanism 1 to perform X-ray imaging. There is a case. Even when the scattered radiation removal grid is used, it is necessary to exchange the scattered radiation removal grid in accordance with the imaging mode. For this reason, in these Bucky mechanisms 1, the structure which can perform suitably the attachment or detachment operation | work of a scattered radiation removal grid is employ | adopted.

  Hereinafter, the configuration of the bucky mechanism 1 will be described. FIG. 4 is a schematic plan view of the bucky mechanism 1.

  The bucky mechanism 1 includes a grid support portion 31 including a pair of guide members 33 that support the scattered radiation removal grid 32 inserted from the grid insertion port 10. In the state where the scattered radiation removal grid 32 is supported, the grid support section 31 inserts the scattered radiation removal grid 32 from the grid insertion port 10 with respect to the support plate 59 of the bucky mechanism 1 (the horizontal direction in FIG. 4). Can be moved back and forth.

  A handle 34 for attaching / detaching the scattered radiation removing grid 32 is attached to the side of the scattered radiation removing grid 32 having a rectangular shape on the grid insertion port 10 side. Further, a magnet member 35 in which a permanent magnet is enclosed is disposed on the side opposite to the handle 34 in the scattered radiation removal grid 32. Further, a plurality of proximity sensors 36 are disposed at positions facing the magnet member 35 on the support plate 59 of the bucky mechanism 1. Different magnets are encapsulated in the magnet member 35 disposed on the scattered radiation removal grid 32 depending on the type of the scattered radiation removal grid 32. Each proximity sensor 36 identifies the type of the scattered radiation removal grid 32 by detecting the magnetic force in the magnet member 35. Further, an urging member 37 having a spring therein is disposed at a position facing the side opposite to the handle 34 on the support plate 59 of the bucky mechanism 1. The urging member 37 is configured to urge the scattered radiation removal grid 32 toward the grid insertion port 10 (right direction in FIG. 4).

  A grid fixing mechanism is disposed at one end of the bucky mechanism 1 on the grid insertion port 10 side. 5 and 6 are enlarged views of the vicinity of the grid fixing mechanism in the bucky mechanism 1. FIG. 5 shows a case where the fixing claw 53 in the grid fixing mechanism is arranged at a fixed position of the scattered radiation removing grid 32 that contacts the scattered radiation removing grid 32, and FIG. 6 shows a fixing claw in the grid fixing mechanism. 53 shows a case where 53 is arranged at an extraction position of the scattered radiation removal grid 32 that is separated from the scattered radiation removal grid 32.

  The grid fixing mechanism includes a lever 51 that swings about a shaft 52 disposed on the grid support portion 31, a fixing claw 53 that swings about a shaft 54 disposed on the lever 51, and a lever 51. A take-out button 55 having a pin 56 capable of abutting on is provided. The take-out button 55 is urged in the direction away from the lever 51 (the right direction in FIGS. 5 and 6) by the action of the spring 57. The lever 51 is urged clockwise about the shaft 52 by a spring (not shown).

  As shown in FIG. 5, when the fixed claw 53 is disposed at a fixed position of the scattered radiation removal grid 32, the edge on the grid insertion port 10 side of the scattered radiation removal grid 32 comes into contact with the fixed claw 53. Regardless of the urging force of the urging member 37 shown in FIG. 4, the scattered radiation removal grid 32 is fixed at a position in contact with the fixed claw 53.

  In this state, when the eject button 55 is pressed, the pin 56 presses the lever 51, and the lever 51 rotates counterclockwise about the shaft 52. Along with this, the shaft 54 moves together with the fixed claw 53 in a direction away from the scattered radiation removal grid 32 (upward direction in FIGS. 5 and 6), and the fixed claw 53 is separated from the scattered radiation removal grid 32 shown in FIG. Move to the removal position. Thereby, a part of the scattered radiation removal grid 32 is exposed to the outside from the grid insertion port 10 by the urging force of the urging member 37. Note that when the scattered radiation removal grid 32 is taken out, the grid support portion 31 is fixed at the attachment / detachment position of the scattered radiation removal grid 32 as described later.

  In this state, the lever 51 is urged clockwise about the shaft 52 by a spring (not shown), so that the tip of the fixing claw 53 is held at the grid insertion port 10 even when the eject button 55 is stopped. To the side of the scattered radiation removal grid 32 exposed to the outside. In this state, as shown in FIG. 6, the contact portion formed at one end of the lever 51 presses the micro switch 58. Thereby, it can be detected that the scattered radiation removal grid 32 is in the middle of extraction, that is, that the scattered radiation removal grid 32 is in a half-inserted state.

  A crank slider mechanism as a swing mechanism for reciprocating the scattered radiation removal grid 32 is disposed at one end of the bucky mechanism 1 opposite to the grid insertion port 10. 7 to 9 are enlarged views of the vicinity of the crank slider mechanism in the bucky mechanism 1. 7 shows a state in which the crank pin 42 is arranged at the attachment / detachment position of the scattered radiation removal grid 32, FIG. 8 shows a state in which the crank pin 42 is arranged in the fastest position, and FIG. Reference numeral 42 denotes a state where it is arranged at a standby position before the start of X-ray imaging.

  As shown in these drawings, the crank slider mechanism is connected to a crankshaft 41 that rotates by driving of a stepping motor 40 fixed to a support plate 59, and a crank arm 43 that rotates around the crankshaft 41 (see FIG. 8). A crankpin 42 is attached to the tip of the crank arm 43. In addition, a slider 44 having a long hole 45 that can be engaged with the crank pin 42 is attached to the grid support portion 31. The long hole 45 is formed with a direction (vertical direction in FIGS. 7 to 9) orthogonal to the attaching / detaching direction of the scattered radiation removal grid 32 as a longitudinal direction. In this crank slider mechanism, when the stepping motor 40 is driven, the crank pin 42 rotates about the crankshaft 41, so that the grid support 31 together with the scattered radiation removal grid 32 is a long hole 45 formed in the slider 44. Reciprocate in the direction orthogonal to the direction, that is, the left-right direction in FIGS. When the rotation of the crankshaft 41 continues, the grid support portion 31 swings together with the scattered radiation removal grid 32. This standby position is set in advance by experiments or the like.

  The moving speed of the scattered radiation removal grid 32 at this time is as follows when the crankpin 42 is arranged near the edge of the long hole 45 as shown in FIG. 8 when the stepping motor 40 rotates at a constant speed ( 8 is the earliest when the crank pin 42 is arranged near the center of the long hole 45 as shown in FIG. Further, as shown in FIG. 9, when the crank pin 42 is disposed at the standby position between the grid attaching / detaching position shown in FIG. 7 and the fastest position shown in FIG. The removal grid 32 can be arranged at the fastest position shown in FIG. 8 in the shortest time. This standby position is determined in advance by experiments or the like.

  In this X-ray imaging apparatus, when the X-ray imaging is finished and the reciprocating movement of the grid support unit 31 is stopped, the control unit 95 in the Bucky mechanism 1 controls the stepping motor 40, whereby the crank in the crank slider mechanism As shown in FIG. 7, the arm 43 is disposed at a position where the crank pin 42 is closest to the grid insertion port 10. This position is a position where the crank arm 43 becomes a dead point. By disposing the crank arm 43 at this position and disposing the scattered radiation removing grid 32 at the grid attaching / detaching position, the scattered radiation removing grid 32 can be suitably attached to and detached from the Bucky mechanism 1.

  That is, when the crank arm 43 is disposed at the position shown in FIG. 7, the grid support portion 31 that supports the scattered radiation removal grid 32 is disposed closest to the grid insertion port 10. When the scattered radiation removal grid 32 is always arranged on the grid insertion port 10 side, the attachment / detachment work of the scattered radiation removal grid 32 can always be suitably performed in the same state. Therefore, when performing the attaching / detaching operation of the scattered radiation removal grid 32, the operator does not feel uncomfortable due to a difference in the insertion amount and the attachment / detachment position of the scattered radiation removal grid 32. Further, in this case, since the grid support portion 31 that supports the scattered radiation removal grid 32 is disposed closest to the grid insertion port 10 side, when the takeout button 55 in the grid fixing mechanism is pressed, the pin 56 is The lever 51 is pressed, and the lever 51 can be rotated counterclockwise about the shaft 52.

  When the crank arm 43 is disposed at the position shown in FIG. 7, the crank arm 43 is disposed at the dead point, and the movement of the grid support portion 31 is limited. For this reason, even when the extraction button 55 is pressed to take out the scattered radiation removal grid 32, the grid support portion 31 does not move. On the other hand, when the crank arm 43 is arranged at the position shown in FIGS. 8 and 9, the crank arm 43 is not arranged at the dead point. It is executed only with a small holding torque of the motor 40. Therefore, when the extraction button 55 is pressed to take out the scattered radiation removal grid 32, the grid support portion 31 moves even if the pin 56 presses the lever 51, and the lever 51 is centered on the shaft 52. Thus, it cannot be rotated counterclockwise. In the bucky mechanism 1 according to the present invention, when the X-ray imaging is finished and the reciprocation of the grid support portion 31 is stopped, the crank arm 43 is disposed at a position where the crank pin 42 is closest to the grid insertion port 10. This prevents the occurrence of such a problem.

  On the other hand, when the scattered radiation removal grid 32 is arranged at the grid attachment / detachment position, it is suitable for the attachment / detachment of the scattered radiation removal grid 32, but in order to perform X-ray imaging quickly, the scattered radiation removal grid 32 is used. Is preferably held at a standby position optimum for acceleration of the scattered radiation removal grid 32. For this reason, in the X-ray imaging apparatus according to the present invention, when the first operation button 81 in the hand switch 80 is pressed in preparation for X-ray irradiation, the scattered radiation removal grid 32 is changed to the grid shown in FIG. The structure which moves to the stand-by position shown in FIG. 9 from the attachment / detachment position is adopted.

  In addition, even when a device for attaching / detaching a scattered radiation removal grid is added to an existing X-ray imaging apparatus, the X-ray imaging apparatus is not required to install a new signal line when adopting such a configuration. Creates a grid movement signal by superimposing a swing operation start signal for starting the swing operation of the scattered radiation removal grid 32 and a standby position movement signal for moving the scattered radiation removal grid 32 from the grid attachment / detachment position to the standby position. In addition, grid movement signal superimposing means for transmitting the grid movement signal to the signal line 91 is provided.

  FIG. 10 is a schematic diagram showing the grid movement signal superimposing means.

  As will be described later, the high voltage device 5 includes a first switch 85 that closes when the operator presses the second operation button 82 in the hand switch 80 and the swing operation start signal B2 of the scattered radiation removal grid 32 is output. And a second switch 86 that closes when the operator presses the first operation button 81 in the hand switch 80 and outputs an X-ray irradiation preparation start signal. Further, the Bucky mechanism 1 is provided with a +5 volt power source and a photocoupler 88. The photocoupler 88 is used to maintain an insulation state between the high voltage device 5 and the bucky mechanism 1.

  The first switch 85 disposed in the high voltage device 5 is connected to the +5 volt power source and the photocoupler 88 by two lines 91 a and 91 b constituting the signal line 91. The second switch 86 is connected to the two lines 91 a and 91 b constituting the signal line 91 via the capacitor 87 while being in parallel with the first switch 85. When the first switch 85 is closed, a current flows through the signal line 91. On the other hand, when the second switch 86 is closed, a current flows for a short time until the charging of the capacitor 87 is completed.

  Next, an X-ray imaging operation by the above-described X-ray imaging apparatus will be described. FIG. 11 is a time chart showing the X-ray imaging operation.

  When the subject is ready for imaging on the table-type X-ray imaging table 2 or the stand-type X-ray imaging table 3, the operator presses the first operation button 81 on the hand switch 80. Thereby, the X-ray irradiation preparation start signal KC is created in the high voltage apparatus 5. This X-ray irradiation preparation start signal KC is a signal for instructing the X-ray tube 15 to prepare for X-ray irradiation, and this X-ray irradiation preparation start signal KC is sent via a signal line 93 shown in FIG. It is transmitted to the X-ray tube 15. When receiving the X-ray irradiation preparation start signal KC, the X-ray tube 15 starts rotating the rotor for irradiating X-rays and prepares for X-ray irradiation.

  Further, when the X-ray irradiation preparation start signal KC is generated in the high voltage apparatus 5, the second switch 86 shown in FIG. 10 is closed, and a current flows through the signal line 91 for a short time until the capacitor 87 is completely charged. A standby position movement signal A shown in FIG. 11 is generated. This signal is transmitted from the high voltage device 5 to the bucky mechanism 1 via the signal line 91 shown in FIGS. When receiving the short standby position movement signal A, the control unit 95 of the bucky mechanism 1 rotates the stepping motor 40 to move the scattered radiation removal grid 32 from the grid attaching / detaching position shown in FIG. 7 to the standby position shown in FIG. Move.

  When a predetermined lag time elapses after the X-ray tube 15 receives the X-ray irradiation preparation start signal KC, the X-ray tube 15 is ready to emit X-rays. This lag time is stored in advance in the high voltage device 5. And if this lag time passes, the indicator 84 shown in FIG. 1 will light. The lag time is a time during which the rotor in the X-ray tube 15 rotates to a constant speed and X-rays can be irradiated. It takes at least about 1 second for the lag time to elapse. The movement of the scattered radiation removal grid 32 described above is completed during this lag time.

  If the operator confirms that the indicator 84 is lit after the lag time, the operator presses the second operation button 82 on the hand switch 80. Thereby, in the high voltage device 5, the swing operation start signal B2 is created. The swing operation start signal B2 is transmitted to the bucky mechanism 1 via the signal line 91 to which the standby position movement signal A is transmitted. When the control unit 95 of the bucky mechanism 1 receives the swing operation start signal B2 longer than the standby position movement signal A, the controller 95 continuously rotates the stepping motor 40 to start the swing operation of the scattered radiation removal grid 32. .

  That is, as shown in FIG. 11, the scattered radiation removal grid 32 moves based on a grid movement signal C created by superposing the standby position movement signal A and the swing operation start signal B2. Then, the grid movement signal C created by superimposing the standby position movement signal A and the swing operation start signal B2 is transferred from the high voltage device 5 to the bucky mechanism by a single signal line 91 as shown in FIG. 1 is transmitted.

  When the scattered radiation removal grid 32 moves to the position shown in FIG. 8 and the speed of the scattered radiation removal grid 32 reaches the maximum, the bucky mechanism 1 creates the imaging permission signal B1. The photographing permission signal B1 is transmitted to the high voltage device 5 through the signal line 92. When the high voltage device 5 receives the imaging permission signal B1, a high voltage is applied to the X-ray tube 15. Thereby, X-rays are emitted from the X-ray tube 15. That is, when the operator presses the second operation button 82 in the hand switch 80, the swing operation start signal B2 and the imaging permission signal B1 are sequentially generated in a short time, and X-rays are emitted from the X-ray tube 15. Will be.

  As described above, according to the X-ray imaging apparatus described above, when the operator presses the first operation button 81 on the hand switch 80, the scattered radiation removal grid 32 arranged at the grid attachment / detachment position moves to the standby position. Therefore, X-ray imaging can be performed promptly by pressing the second operation button 82 thereafter. At this time, a grid movement signal is created by superimposing the standby position movement signal A for instructing the movement of the scattered radiation removal grid 32 and the swing operation start signal B2 from the high voltage device 5 to the bucky mechanism 1. Since the configuration is such that the movement signal is transmitted to the signal line 91, it is not necessary to install a new signal line even when an attachment / detachment device for the scattered radiation removal grid is added to the existing X-ray imaging apparatus.

  In the embodiment described above, the grid movement signal C is created by the grid movement signal superimposing means using the capacitor 87 shown in FIG. On the other hand, if the control unit 96 of the high voltage apparatus 5 is programmable and can generate a short swing operation start signal B2 from the X-ray irradiation preparation start signal KC, a grid movement signal as shown in FIG. There is no need to use superimposing means.

  In the above-described embodiment, the scattered radiation removal grid 32 is moved in a reciprocating movement path including a standby position suitable for accelerating the scattered radiation removal grid 32 and a grid attachment / detachment position for attaching / detaching the scattered radiation removal grid 32. Although the rocking is performed, the grid attaching / detaching position may be a position outside the rocking path. That is, the grid attachment / detachment position may be disposed at a position off the swing path, and the scattered radiation removal grid 32 may be disposed at the grid attach / detach position off the swing path after the end of the swing operation.

  Furthermore, in the above-described embodiment, the scattered radiation removal grid 32 is swung using the crank slider mechanism, but the grid is obtained by converting the driving force of the motor into linear motion, for example, using a linear guide or the like. Other mechanisms may be used as long as the mechanism moves.

DESCRIPTION OF SYMBOLS 1 Bucky mechanism 2 X-ray imaging stand 3 X-ray imaging stand 4 X-ray irradiation part 5 High voltage apparatus 10 Grid insertion port 11 Top plate 12 Moving mechanism 15 X-ray tube 16 Collimator 22 Bulkhead 23 Lifting member 31 Grid support part 32 Scattering ray Removal grid 33 Guide member 34 Handle 37 Energizing member 40 Stepping motor 41 Crank shaft 42 Crank pin 43 Crank arm 44 Slider 45 Long hole 51 Lever 52 Axis 53 Fixing claw 54 Axis 55 Eject button 56 Pin 57 Spring 59 Support plate 80 Hand switch 81 First operation button 82 Second operation button 91 Signal line 92 Signal line 93 Signal line 95 Control unit 96 Control unit 97 Control unit

Claims (4)

In a radiation imaging apparatus comprising a radiation generation source, a radiation detection unit that detects radiation irradiated from the radiation generation source and passed through the subject, and a bucky mechanism that swings a scattered radiation removal grid,
The scattered radiation removal grid is disposed in the Bucky mechanism and is swung by a motor in a reciprocating path including a standby position suitable for accelerating the scattered radiation removal grid. A rocking mechanism that is disposed at a grid attachment / detachment position for attaching / detaching the hooky part to / from the bucky part ,
A high-voltage device including an input unit having a first operation unit for preparing radiation irradiation and a second operation unit for irradiating radiation from the radiation generation source, and applying power to the radiation generation source;
Grid moving means for moving the scattered radiation removal grid from the grid attachment / detachment position to the standby position when the first operation unit is operated;
A radiation imaging apparatus comprising: The radiographic apparatus according to claim 1,
A grid standby position movement signal for moving the scattered radiation removal grid, which is created when the first operation unit is operated to prepare for radiation irradiation, from the grid attachment / detachment position to the standby position, and radiation A grid movement signal is created by superimposing a rocking motion start signal for starting the rocking motion of the scattered radiation removal grid created when the second operation unit is operated for irradiation. A radiation imaging apparatus that transmits a grid movement signal to a signal line extending from the high-voltage device to the bucky mechanism. The radiation imaging apparatus according to claim 2,
A first switch that is closed when the second operation unit is operated is connected to the signal line;
A radiation imaging apparatus, wherein a second switch that is closed when the first operation unit is operated is connected to the signal line in parallel with the first switch via a capacitor. In the radiography apparatus in any one of Claims 1-3,
The swing mechanism is
A crank arm connected to a crankshaft that rotates by driving of the motor, rotates around the crankshaft, and is provided with a crankpin;
A long hole that engages with the crankpin is formed, and a slider connected to a grid support portion that supports the scattered radiation removal grid inserted from the grid insertion port,
A crank slider mechanism that reciprocally moves the grid support portion in a direction intersecting a long hole in the slider by rotating the crank arm around the crankshaft;
The grid attachment / detachment position is
A radiation imaging apparatus in which the crank pin is closest to the grid insertion port.

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