JP2015146885A - X-ray imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong a life of a bulb by preventing excessive anode rotation and minimize delay between an imaging instruction and an imaging start.SOLUTION: An X-ray imaging apparatus includes an imaging part equipped with a rotary anode X-ray tube device and an X-ray detector, a control part for controlling operation of the imaging part, an operation tool operated by an operator, and an input device for causing the rotary anode X-ray tube device to be operated by the operation of the operation tool and sending a command to start X-ray exposure to the control part. Furthermore, the X-ray imaging apparatus includes a sensor for detecting the approach of an object in the operation tool itself or in its vicinity. The control part detects by the sensor that operation of an imaging instruction is performed before the operation is performed, and increases rotation speed of a rotary anode prior to the imaging instruction.

Description

  The present invention relates to an X-ray imaging apparatus using a rotating anode X-ray tube apparatus, and more particularly to a technique for optimizing the operation of the rotating anode.

  As an X-ray source of an X-ray imaging apparatus, an X-ray tube apparatus using a rotating anode is frequently used. The rotating anode has an advantage that the anode, which is a target that emits X-rays, is rotated at a high speed with respect to the electron beam to disperse the heat concentration caused by the electron beam hitting only one point of the target and prevent the target from being consumed. .

  A general X-ray imaging apparatus has both functions of a fluoroscopic mode in which X-ray exposure is continuously performed at a relatively low X-ray output and an imaging mode in which single X-ray exposure is performed at a relatively high X-ray output. Yes. In the imaging mode, since the electric power applied to the X-ray tube increases, it is necessary to rotate the anode at a higher speed than in the fluoroscopic mode from the viewpoint of heat capacity. Usually, the anode rotation speed at the time of photographing is about three times the rotation speed at the time of fluoroscopy. For this reason, for example, when imaging is performed when a target imaging target is determined while performing fluoroscopy, the rotation of the anode is performed from when an operation instructing imaging is performed until imaging (X-ray exposure) is actually performed. The speed needs to be increased to a speed at which shooting can be performed stably, and a certain delay occurs between the shooting instruction and the start of shooting. This delay leads to the operator not being able to shoot at the optimal timing, and for the subject to a longer breath holding time.

  In order to eliminate the delay in shooting, it is conceivable to rotate the anode at the same rotation speed during fluoroscopy, but in this case, the anode is rotated excessively in inspections with low imaging frequency. The service life is greatly reduced.

  On the other hand, Patent Document 1 proposes a technique for determining an allowable minimum value of the anode rotation speed at the time of photographing based on photographing conditions obtained from the fluoroscopic conditions at the time of fluoroscopy, and rotating the anode during fluoroscopy with this value. Has been.

JP 2007-179817 A

  The technique described in Patent Document 1 can reduce the rotation burden of the tube as compared with the case where the anode is rotated at the same rotational speed as when photographing at the time of fluoroscopy, but is required for fluoroscopy even during fluoroscopy. Since the anode is rotated at a higher speed than the rotating speed, the effect of preventing the life of the tube from being reduced is limited.

  An object of the present invention is to prevent the anode from rotating excessively, thereby extending the life of the tube, and to minimize the delay between the shooting instruction and the start of shooting.

  In order to solve the above problems, the X-ray imaging apparatus of the present invention detects an imaging instruction by an operator before the operation is performed, and thereby starts driving the rotating anode prior to the imaging instruction (rotating anode). (Means for increasing the rotation speed).

  That is, the X-ray imaging apparatus of the present invention includes an imaging unit including a rotary anode X-ray tube device and an X-ray detector, a control unit that controls the operation of the imaging unit, and an operating tool operated by an operator. An input device for operating the rotary anode X-ray tube device by the operation of the operation tool to send an instruction to start X-ray exposure to the control unit, and an object approaching the operation tool itself or in the vicinity thereof The control unit inputs a signal from the sensor, and controls the rotation of the rotary anode of the rotary anode X-ray tube device according to the signal.

  According to the present invention, prior to the operator operating the operating tool that directs shooting, the anode rotation speed is set to the rotational speed required for shooting when a part of the body such as a finger or a foot is brought close to the operating tool. By changing to, it is possible to shorten the time from the actual operation of the operation tool to the anode rotation speed at which X-ray exposure is possible, and to prevent the deviation of the imaging timing. Further, since the state in which the anode rotation speed is excessively increased can be eliminated, it is possible to prevent a decrease in the life of the tube.

1 is an overall block diagram showing an embodiment of an X-ray imaging apparatus of the present invention. Functional block diagram of control unit Perspective view showing the outline of the input unit The figure which shows the example of arrangement of an operation tool and a sensor Graph showing the relationship between the detection voltage of the sensor and the distance between the object and sensor Flow chart showing the operation of the first embodiment It is a figure which shows the change of the anode rotation angle by imaging | photography instruction | indication, (a) is the case of the X-ray imaging device of 1st embodiment, (b) shows the case of a prior art. Flow chart showing the operation of the second embodiment The graph which shows the relationship between the detection voltage of two sensors, and the object-sensor distance. Flow chart showing the operation of the third embodiment The figure which shows the example of arrangement of an operation tool and a sensor Table showing correspondence between switch function switching and sensor signal on / off switching in the fourth embodiment

  The X-ray imaging apparatus of this embodiment includes an imaging unit (10) including a rotating anode X-ray tube device (11) and an X-ray detector (15), and a control unit (10) that controls the operation of the imaging unit (10). 30), and an input unit (20) having an operation tool (21) operated by the operator, operating the rotary anode X-ray tube device by the operation of the operation tool (21), and starting X-ray irradiation, And a sensor (40) for detecting the approach of an object in the vicinity of the operation unit (20). The control unit (30) receives a signal from the sensor (40) and controls the rotation of the rotating anode of the rotating anode X-ray tube device according to the signal.

  Hereinafter, the configuration and operation of the X-ray imaging apparatus of the present embodiment will be described with reference to the drawings. FIG. 1 shows the overall configuration of the X-ray imaging apparatus. In this X-ray imaging apparatus, an X-ray tube 11 that is an X-ray source and an X-ray plane detector (hereinafter simply referred to as an X-ray detector) 15 that detects X-rays are disposed opposite to each other with a subject 70 interposed therebetween. The X-ray emitted from the X-ray tube 11 and transmitted through the subject 70 is detected by the X-ray detector 15 to obtain a transmitted X-ray image. Transmission X using the imaging unit 10 composed of a line detector 15, an X-ray high voltage device 12 for driving the X-ray tube 11, and a signal indicating transmitted X-rays detected by the X-ray detector 15. An image processing calculation unit 50 that generates a line image, a display unit 60 that displays image data generated by the image processing calculation unit 50 as an image, a control unit 30 that controls the entire apparatus, and an operator that includes the control unit 30 System operation unit (input unit) for inputting and instructing the necessary commands and conditions to each unit And a 20.

  The X-ray tube 11 is not shown in detail, but a predetermined space is placed in the tube, a cathode for irradiating an electron beam, and an anode with a target are arranged, and the anode is rotated at high speed. However, it consists of a rotating anode X-ray tube device having a structure in which X-rays emitted from a target upon irradiation with an electron beam are extracted from an X-ray window, and an X-ray high voltage device 12 is connected thereto. Further, the X-ray tube 11 is provided with a diaphragm device 13 for controlling the X-ray irradiation direction.

  The X-ray high voltage apparatus 12 includes a high voltage generator 121 that applies a high voltage between the cathode and anode of the X-ray tube 11 and an anode rotation drive unit 123 that controls the rotation of the anode.

  The X-ray plane detector 15 is for detecting X-rays irradiated from the X-ray tube 11 and transmitted through the subject 70, and is a flat panel detector (FPD) using a commonly used TFT element. Can be used. An X-ray image intensifier that converts an X-ray transmission image into a visible light image, an optical lens that forms an image of the X-ray image intensifier, and an X-ray image intensifier formed by the optical lens. You may use the two-dimensional X-ray detector comprised from the combination of the CCD television camera etc. which image | photograph a visible light image. The X-ray flat panel detector 15 is connected to a read control unit 16 that controls a read operation of data from the X-ray flat panel detector 15.

  The subject 70 is usually placed in the space of the imaging unit 10 composed of the X-ray tube 11 and the X-ray detector 15 while being laid on the table 17 of the fluoroscopic table.

  The image processing calculation unit 50 performs necessary processing, noise reduction processing, contrast correction processing, and the like on the data read from the X-ray detector 15 under the control of the reading control unit 16, and transmits the transmitted X-ray image. Get. When the apparatus is operating in the fluoroscopic mode, a moving image that is a time-series image of a transmitted X-ray image is created.

  The control unit 30 includes the above-described X-ray high voltage device 12 (the high voltage generation unit 121 and the anode rotation driving unit 123), a fluoroscopic table (not shown) including the table 17, the read control unit 16, the image processing calculation unit 50, and the like. As shown in FIG. 2, the X-ray control unit 31 that controls the operation of the X-ray high-voltage device 12 and the fluoroscopy / imaging that controls the start / end of the fluoroscopy / imaging operation, as shown in FIG. An operation control unit 32, a fluoroscopic table operation control unit 33 that controls the operation (movement, rotation, etc.) of the fluoroscopic table, and an image processing control unit 34 that controls image processing in the image processing calculation unit 50 are provided. Further, the fluoroscopic / imaging operation control unit 32 is provided with an imaging operation detection unit 35 that inputs a signal from the sensor 40 disposed in the vicinity of the system operation unit 20 and detects the operation of the operator based on the signal. Yes.

  The control unit 30 can be configured by one CPU together with the image processing calculation unit 50, and is realized by a control program incorporated in advance in the CPU. The control program is executed by the operator operating the system operation unit 20, and predetermined control is performed. Control conditions and parameters and data necessary for program execution are input to the control unit 30 via the system operation unit 20. Although not shown in the illustrated embodiment, a memory unit that records necessary data and data that is being processed by the control unit 30 or the image processing calculation unit 50 may be provided in the CPU or separately from the CPU.

  The X-ray control unit 31 operates the high-voltage generation unit 121 and the anode rotation driving unit 123 of the X-ray high-voltage device 12 according to preset fluoroscopy conditions, imaging conditions, or conditions input from the system operation unit 20. X-rays are irradiated from the X-ray tube 11 under conditions of a predetermined tube voltage and a predetermined anode rotation speed. In the case of imaging, single or multiple X-ray irradiation is performed, and in the case of fluoroscopy, continuous X-ray irradiation is performed.

  When the operation tool provided in the system operation unit 20, specifically, the fluoroscopic start switch or the imaging start switch is operated, the fluoroscopic / imaging operation control unit 32 commands to start and end fluoroscopy and start imaging. Is sent to the X-ray control unit 31. Further, the fluoroscopic / imaging operation control unit 32 sends a command to the anode rotation control unit 123 when the imaging operation detection unit 35 receives a signal from the sensor 40, and the anode drive unit so that the anode rotation angle becomes a predetermined rotation angle. (Not shown) is operated.

  The fluoroscopic table operation control unit 33 operates the driving mechanism of the fluoroscopic table by operating an operation tool provided in the system operation unit 20, for example, a joystick, and moves the table 17 on which the subject 70 is arranged to the imaging unit 10. , Move or rotate horizontally or vertically.

  The image processing control unit 34 receives input of image processing conditions by operating an operation tool provided in the system operation unit 20, for example, a keyboard or a mouse, and performs image processing such as gain adjustment, threshold processing, and various corrections. The image processing includes display image processing, and controls enlargement / reduction, rotation, movement, simultaneous display or superimposition display of other images, and the like.

  The system operation unit 20 includes an operation tool for an operator to operate. The system operation unit 20 is used to input an instruction to the control unit 30 described above, and is mounted on a console table integrated with the display unit 60. An appearance of a configuration example of the system operation unit 20 is shown in FIG. As shown in FIG. 3, the system operation unit 20 includes an upper surface of a console table 120 formed integrally with a housing 110 that houses a control unit 30, an image processing arithmetic unit 50, and the like configured by a CPU, 110 is arranged near the floor surface. On the console table 120, a display (display unit) 60 for displaying a transmission X-ray image, a GUI, and the like is installed.

  As the system operation unit 20, various switch buttons, a joystick, a mouse, a keyboard, and the like for inputting shooting conditions, shooting parameters, commands, and the like are installed on the upper surface of the console table 120 in a predetermined arrangement. In the embodiment shown in FIG. 2, the switch 21 for instructing photographing is a cylindrical switch. A switch installed near the floor of the housing 110 is a switch for instructing the start of photographing or fluoroscopy, and includes one or a plurality of foot switches 22.

  A switch (operation tool) for starting photographing is provided with a sensor (not shown) for detecting an operation by the operator before the photographing switch is operated, that is, a sensor for detecting the approach of an object. . A signal from the sensor is input to the imaging operation detection unit 35 of the fluoroscopic / imaging operation control unit 32, and the rotation speed of the anode is controlled. Thus, the anode rotation speed is switched to a high speed before the imaging switch is actually operated, and the time from the operation of the imaging switch 21 to the rotation speed at which the anode rotation speed can be irradiated with X-rays is shortened.

  FIG. 4 shows an embodiment in which the sensor 40 is fixed to the photographing switch 21 provided on the upper surface of the console table 120. The photographing switch 21 shown in the figure is a cylindrical switch erected on the upper surface of the console table 120, and a push button 21a for generating a photographing start control signal by an operator's push-down operation is provided on the inclined surface of the tip. . The sensor 40 is fixed to a portion of the push button 21a that is touched by the operator's finger. 4 shows a case where the sensor 40 is fixed on the upper surface of the push button 21a. However, the location where the sensor 40 is fixed is appropriately changed according to the shape and position of the photographing switch 21. be able to. 4 shows a state where a single sensor 40 is fixed, the sensor 40 may be a combination of a plurality of sensors or a plurality of types of sensors.

  Specifically, as the sensor 40 that detects the proximity of an object, an infrared sensor that includes a capacitance sensor that detects a change in capacitance and an infrared light transmitting / receiving element, and that detects a change in the amount of infrared light entering the light receiving element. Use a known displacement sensor or distance sensor such as a sensor, an ultrasonic transmission / reception circuit, an ultrasonic sensor that detects a change in the return time of the reflected wave, and a triangulation sensor that combines a light emitting element and a light receiving element. Can do. These sensors can measure the distance between an object and the sensor by changing the capacitance, the amount of received infrared light, the ultrasonic feedback time, etc. to the voltage, and the resolution of the response frequency and detection distance of each sensor. Appropriate ones can be selected and used according to.

  FIG. 5 shows a relationship (VL curve) between the detection voltage V and the object-sensor distance L in a typical distance sensor. As shown in the figure, the detection voltage has a maximum value Vp at a predetermined distance, and has a characteristic that attenuates as the distance increases. Based on the VL curve of the sensor, a detection voltage Vd obtained at the distance Ld to be detected is set in the photographing operation detection unit 35 as a threshold value. The photographing operation detection unit 35 detects that the distance between the object and the sensor is equal to or less than the distance Ld, that is, that the object has approached the sensor 40 when the detection voltage V becomes equal to or greater than the set threshold value. Note that the distance Ld to be detected can be arbitrarily set in consideration of the detection distance suitability of the sensor 40. In order to shorten the time from when the photographing switch is actually operated to when the anode rotation speed reaches the predetermined rotation speed, it is preferable that the distance Ld is long. In order to reduce it as much as possible, about 10 cm or less is preferable.

  Next, based on the above-described configuration of the X-ray imaging apparatus, a processing procedure by the control unit 30 will be described.

<First Embodiment>
FIG. 6 shows an embodiment of the processing procedure. This figure shows a procedure after the conditions for fluoroscopy and photographing have already been input through the system operation unit 20.

  Description will be made centering on a case where fluoroscopy and imaging are continuously performed, which is common in an examination using an X-ray imaging apparatus. First, when a fluoroscopy start switch (not shown) is operated (S101), fluoroscopy in which X-ray exposure is continuously performed with a relatively low X-ray output is started (S102). At this time, the rotation speed of the anode of the X-ray tube 11 is set to a low speed. A transmission X-ray image obtained by fluoroscopy is displayed on the display unit 60. The operator performs imaging by single X-ray exposure at a desired timing while confirming the transmitted X-ray image of the subject displayed on the display unit 60.

  Shooting is started when the operator presses the push button 21 a of the shooting start switch 21. At that time, the sensor 40 fixed to the upper surface of the push button 21a detects the operation of the operator, that is, that the hand is brought close to the push button 21a (S103). The fluoroscopic / imaging operation control unit 32 determines that an object has approached when the detection voltage from the sensor 40 input by the imaging operation detection unit 35 is equal to or higher than a preset threshold value Vd, and the control signal is transmitted to the X-ray. The data is sent to the control unit 31. The X-ray control unit 31 thereby controls the rotary anode driving unit 123 to switch the rotation speed of the anode from the low-speed rotation during fluoroscopy to the high-speed rotation during imaging (S104). Depending on the performance of the sensor 40, for example, when it is detected that the operator's finger has approached the push button 21a by several tens of millimeters, the rotation speed of the anode is switched.

  Next, when the operator actually operates the push button 21a (S105), the X-ray control unit 31 drives the high voltage generation unit 4 when the anode rotation speed increases to the speed set as the rotation speed at the time of imaging. X-ray exposure is performed under predetermined conditions (S106). Although not shown in the flow of FIG. 5, X-ray exposure (imaging) is repeated once or a plurality of times as necessary, and the anode rotation is stopped after one or a plurality of times of X-ray exposure ( S107).

  FIG. 7A shows changes in the anode rotation speed from step S102 to step S106. In the figure, the horizontal axis represents time, and the vertical axis represents anode rotation speed. Further, the anode rotation speed Ra is the fluoroscopic rotation speed, Rb is the imaging rotation speed, t1 is the time when the sensor 40 detects the approach of the operator (the time when the detection signal is output from the sensor 40), and t2 is pressed by the operator. The time when the button 21a is operated, t3 is the time when the X-ray exposure is performed. For comparison, FIG. 7B shows changes in the anode rotation speed from the conventional imaging switch operation to X-ray exposure.

  As shown in FIG. 7B, conventionally, when the photographing switch is operated at t2, the rotation speed of the anode is increased from that point, and at time t3 when it is detected that the rotation speed has reached a predetermined speed Rb. X-ray exposure is performed, and the interval ΔT0 between t2 and t3 is about 1 second. On the other hand, the time from when the operator's finger approaches the push button 21a about several tens of mm to when the operator actually presses the push button 21a is about several tens of milliseconds to several hundreds of milliseconds. Accordingly, when the anode rotation speed is increased simultaneously with the detection signal from the sensor 40 as shown in FIG. 7A, the time ΔT1 from when the actual push button 21a is pressed until the target anode rotation speed Vb is reached. Can reduce the time difference ΔT0 in FIG. 7B by several% to several tens of%.

  Returning to the flow of FIG. 6, after the detection voltage from the sensor 40 becomes equal to or higher than the threshold value and the anode rotation speed is switched to high speed rotation (S104), the photographing switch 21 is not operated even after a predetermined time has elapsed (S105). The process proceeds to step S108. Here, it is determined whether or not fluoroscopy is being performed. If fluoroscopy is being performed (S108), the anode rotation speed is returned to the low-speed rotation state, and fluoroscopy is continued until the fluoroscopy end switch is operated (S109). Thus, for example, when an operator or other person or object approaches the photographing switch 21 during fluoroscopy and the sensor 40 detects it, if the photographing switch 21 is not operated, the anode rotation speed is set at the time of fluoroscopy. It returns to a low-speed rotation state and fluoroscopy is continued. The fluoroscopy ends when the fluoroscopy end switch is operated (S109).

  The above is a flow when shifting from fluoroscopy to photographing, but when not performing fluoroscopy, the process proceeds from step S101 to S103. If the approach of the object is detected by the sensor 40 in step S103, the rotation speed of the anode starts to be increased (S104). When the imaging switch is operated (S105), the X-ray exposure is performed when the anode rotation speed reaches a predetermined speed. Performing the shooting (S106) is the same as when performing fluoroscopy. If the photographing switch 21 is not operated even after a predetermined time has elapsed after increasing the anode rotation speed, the process proceeds to step S108. However, since fluoroscopy is not performed in this flow, the process proceeds from step S108 to step S107. Transition to stop the rotation of the anode. After the anode rotation is stopped, if the photographing is not finished (S110), the process returns to the beginning.

  As described above, by switching the anode rotation speed from a low speed to a high speed prior to the pressing operation of the imaging switch (push button) 21 based on the sensor signal from the sensor 40, the X-ray exposure is performed after the imaging switch is pressed down. Can be shortened. In addition, during fluoroscopy, the anode only needs to be rotated at a low anode rotation speed necessary for fluoroscopy, so that excessive anode rotation can be prevented and the life of the tube can be extended.

  In the above description, the case where the shooting switch is a cylindrical switch provided on the upper surface of the console table has been described as an example. However, the same applies to the case where the shooting switch is the foot switch 22 installed near the floor surface. It is possible to apply. However, since the foot switch is generally operated by the operator's foot, the area where the foot contacts is wide. Therefore, it is preferable that the sensor for detecting the approach of the object to the foot switch is a sensor group consisting of a plurality of sensors 40, which are equally arranged on the surface operated by the foot of the foot switch 22. When the detection voltage of any of the sensors constituting the sensor group becomes equal to or higher than the threshold value, the imaging operation detection unit 35 determines that there is a foot switch operation and changes the anode rotation speed.

Second Embodiment
This embodiment is also the same as the first embodiment in that a sensor for detecting the approach of an object is provided in the photographing switch itself or in the vicinity thereof, and the anode rotation speed is changed according to the detection voltage from the sensor. However, in this embodiment, the anode rotation speed is not changed immediately when the detection voltage from the sensor 40 exceeds the threshold value, but an additional condition is added to change the anode rotation speed to change the anode rotation speed. Prevents malfunction. FIG. 8 shows an embodiment in which the number of detections is added as an additional condition. FIG. 8 shows a portion (portion surrounded by a dotted line) corresponding to steps S103 and S104 in the flow of FIG. The other steps shown in FIG. 6 are the same in this embodiment, and illustration and description thereof are omitted.

  First, the photographing operation detection unit 35 determines whether or not the detection voltage V from the sensor 40 is equal to or higher than a preset threshold value Vd (S201). Next, when the number n of times when the detected voltage is equal to or higher than the threshold is the preset number nd (S202), it is determined that the photographing operation is performed (S203), and a control signal is sent to the anode rotation drive control unit 123 to Is rotated (S104). The number of times nd is not particularly limited. However, since the number of times nd varies depending on the examination place, the operator, and the like, it is preferable that the operator can set the number nd in advance via the system operation unit 20.

  In this embodiment, when the imaging switch is pushed down immediately after one approach to the imaging switch (push button) 21, the time from the pressing operation to the X-ray exposure is conventional (FIG. 6B). )), But, for example, when an object held by the operator in the vicinity of the photographing switch 21 or the hand itself moves frequently during fluoroscopy, it is possible to prevent unnecessary changes in the anode rotation speed, thereby It is possible to prevent the life of the sphere from decreasing.

<Third Embodiment>
This embodiment is similar to the second embodiment in that the condition for changing the anode rotation speed is the same as that of the second embodiment, but this embodiment is characterized by using a plurality of sensors having different detection distances. The detection voltage is determined in combination, and the photographing operation of the operator is reliably detected.

  FIG. 9 shows detection voltage characteristics of a plurality of sensors having different detection distances. In the figure, for example, the sensor 41 is a sensor having high detectability at a relatively short distance (for example, several mm), and the sensor 42 is sensor having high detectability at a relatively long distance (for example, several cm). For the sensor 41, the distance to detect that the object has approached is Ld1, and for the sensor 42, the distance to detect that the object has approached is Ld2, and the detection voltages corresponding to these distances Ld1 and Ld2 are the threshold values Vd1 and Vd2. This is set in the shooting operation detection unit 35.

  FIG. 10 shows an example of a procedure when two sensors having different detection distances are used as sensors. FIG. 10 shows a portion (portion surrounded by a dotted line) corresponding to steps S103 and S104 in the flow of FIG. The other steps shown in FIG. 6 are the same in this embodiment, and illustration and description thereof are omitted.

  The photographing operation detection unit 35 detects the detection voltage from the sensors 41 and 42 (S103). The fluoroscopic / imaging operation control unit 32 performs an imaging operation when the imaging operation detection unit 35 has a detection voltage from the sensor 41 equal to or higher than Vd1 and a detection voltage from the sensor 41 is equal to or higher than Vd2 (S301, S302). (S303), a control signal is sent to the anode rotation drive control unit 123, and the rotation speed of the anode is changed (S304).

  According to the present embodiment, similarly to the second embodiment, it is possible to prevent malfunction due to movement other than the button operation of the operator.

<Fourth embodiment>
The present embodiment is applied to an X-ray imaging apparatus including a foot switch to which a plurality of functions can be assigned and a switch for switching the function of the foot switch. In such an X-ray imaging apparatus, the foot switch is provided. In addition, the sensor signal from the sensor 40 that detects the approach of the object is turned ON / OFF in conjunction with the changeover switch.

  As described with reference to FIG. 2, the imaging switch 21 for issuing an imaging (X-ray exposure) command is provided on the upper surface of the console table 120, but the foot switch also has the function. be able to. Before the foot switch is operated, the operation of the operator is detected and the anode rotation speed is controlled. In the present embodiment, as in the first embodiment, the sensor 40 may be provided on the push button 21a of the photographing switch 21. Hereinafter, this embodiment will be described in detail. Also in this embodiment, the overall configuration and the configuration of the system operation unit 20 are the same as those shown in FIGS. The elements shown in FIGS. 1 and 3 are cited.

  FIG. 11 shows a configuration example of the foot switch of the X-ray imaging apparatus of the present embodiment and a state in which a sensor is arranged on the foot switch. The foot switch 22 is installed in the part near the floor surface of the console table 120 (FIG. 2) so that it may show in figure. In the example shown in FIG. 11, a pair of left and right foot switches 221 and 222 and a changeover switch 223 that switches between the fluoroscopic and photographing functions are provided. The left and right foot switches 221 and 222 are fluoroscopic switches or photographing switches. When one is a fluoroscopic switch and the other is a photographing switch, both foot switches are fluoroscopic switches having different fluoroscopic conditions or photographing switches having different photographing conditions. I can take the case. The function assignment to the left and right foot switches can be arbitrarily selected by the operator from those set as defaults in advance, and the changeover switch 223 is used for switching the functions of both switches. The functions assigned to the left and right foot switches 221 and 222 are displayed on the display unit 60 and can be confirmed by the operator.

  Each of the left and right foot switches 221 and 222 is provided with a sensor 40 that detects the approach of an object. In general, since the foot switch is operated by an operator's foot, the area with which the foot contacts is wide. For this reason, in this embodiment, a sensor group consisting of a plurality of sensors 40 is fixed to the surfaces of the foot switches 221 and 222 so that even when a foot approaches a part of the foot switch, it can be detected.

  Also in the present embodiment, the detection voltage of the sensor 40 is input to the photographing operation detection unit 35. The photographing operation detection unit 35 turns the detection operation on and off based on the function assigned to the foot switch. That is, only when one of the foot switches is assigned the function of the photographing switch, the detection signal from the sensor group fixed to the foot switch is input, and the approach of the object is determined by the threshold value. FIG. 12 shows a correspondence table between the functions assigned to the left and right foot switches and the detection functions of the photographing operation detection unit 35. In the example shown in FIG. 12, each of the fluoroscopic mode and the photographing mode operates under two different conditions A and B, and the left and right foot switches 221 and 222 are assigned functions so as to instruct fluoroscopic and photographing under these different conditions. ing.

  Next, since the outline of the processing procedure in the present embodiment is the same as that in FIG. 6, the following description will be given with reference to each step in FIG.

  When the fluoroscopic start switch is operated and fluoroscopy is performed (S101, S102), when the detection voltage of the sensor group in which the detection operation is ON in the photographing operation detection unit 35 is equal to or higher than the threshold value Vd, The anode rotation speed is changed to switch from low speed rotation to high speed rotation (S103). Here, the detection of the approach of an object may be determined as an approach when one sensor in the sensor group has a detection voltage equal to or greater than a threshold value, or an approach is present when the number of sensors is a predetermined number or more. You may judge. Similarly to the processing of FIG. 8, the number of times that the detected voltage becomes equal to or greater than the threshold value may be counted, and it may be determined that the photographing switch is operated when the number of times is equal to or greater than the predetermined number. Alternatively, sensors having different detection distances are used as a plurality of sensors constituting the sensor group, and it is determined that the photographing switch is operated when the detection voltage exceeds a threshold value from different types of sensors, as in the process of FIG. (S103).

  If it detects that an object is approaching, it changes the anode rotation speed, switches from low-speed rotation during fluoroscopy to high-speed rotation during shooting, and then reaches the predetermined high-speed rotation when the shooting switch is actually operated. The X-ray exposure at the time is the same as in the first embodiment (S104 to S107).

  On the other hand, a detection voltage corresponding to the distance of an approaching object is also output for a sensor fixed to a foot switch to which a function other than shooting is assigned. The detection power from this sensor is output by the shooting operation detection unit 35. Since it is OFF, the anode rotation speed is not changed. Further, when the function of the foot switch is switched by operating the changeover switch 225, the detection operation of the photographing operation detection unit 35 is switched ON / OFF according to the change in accordance with the table shown in FIG.

  According to this embodiment, even when the function of the foot switch is switched, the anode rotation speed can be appropriately switched using the sensor fixed to the switch to which the photographing switch function is assigned.

  According to the present invention, it is possible to provide an X-ray imaging apparatus capable of operating an imaging mode at an appropriate timing without imposing an excessive burden on the X-ray tube.

DESCRIPTION OF SYMBOLS 11 ... X-ray tube, 12 ... X-ray high voltage apparatus, 15 ... X-ray plane detector, 17 ... Table, 20 ... System operation part (input part), 21 ... Shooting switch (operating tool) 22, 221, 222 ... foot switch, 223 ... changeover switch, 30 ... control unit, 32 ... fluoroscopic / shooting operation control unit, 35 ... shooting operation Detection unit, 40, 41, 42 ... sensor, 50 ... image processing operation unit, 60 ... display unit, 70 ... subject, 120 ... console table.

Claims (7)

An imaging unit including a rotary anode X-ray tube device and an X-ray detector, a control unit that controls the operation of the imaging unit, and an operation tool that is operated by an operator. An X-ray imaging apparatus comprising: an input device that operates the X-ray tube device and starts an X-ray exposure to the control unit;
A sensor for detecting the approach of an object is provided in or near the operation tool itself,
The X-ray imaging apparatus, wherein the control unit inputs a signal from the sensor and controls the rotation of the rotating anode of the rotating anode X-ray tube apparatus according to the signal. The X-ray imaging apparatus according to claim 1,
The X-ray imaging apparatus, wherein the control unit increases the rotation speed of the rotary anode when the intensity of a signal from the sensor is equal to or greater than a threshold value. The X-ray imaging apparatus according to claim 2,
The X-ray imaging apparatus characterized in that the control unit increases the rotational speed of the rotating anode when the number of times that the intensity of the signal from the sensor is equal to or greater than a threshold value is equal to or greater than a predetermined number. The X-ray imaging apparatus according to claim 1,
The sensor includes two or more types of sensors having different detection distances,
The X-ray imaging apparatus, wherein the control unit increases the rotation speed of the rotary anode when the intensity of signals from the two or more types of sensors is equal to or greater than a threshold value. The X-ray imaging apparatus according to claim 1,
The X-ray imaging apparatus, wherein the operation tool is a switch or a button operated by the operator's hand or finger. The X-ray imaging apparatus according to claim 1,
The X-ray imaging apparatus, wherein the operation tool is a foot switch operated by the operator's foot. The X-ray imaging apparatus according to claim 6,
The input unit has a switching unit that switches the function of the foot switch to either a photographing mode or a fluoroscopic mode,
The control unit changes the rotational speed of the rotating anode in accordance with a signal from the sensor only when the function of the foot switch is switched to the imaging mode by the switching unit. apparatus.

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