X-ray imaging device

Abstract

The present invention provides an X-ray imaging apparatus that can avoid contact with the monitor when moving the X-ray generator. [Solution] The X-ray imaging unit comprises a top plate on which a subject is mounted, an X-ray generator that irradiates the subject with X-rays, an X-ray detector that detects the X-rays that have passed through the subject, a support column that supports the X-ray generator, and a drive mechanism that moves the position of the X-ray generator. The calculation unit receives the drive amount of the drive mechanism from the control unit and determines the distance between the end of the X-ray imaging unit closest to the monitor and the monitor. If the distance is smaller than a predetermined reference distance, the unit instructs the control unit to stop the operation of the drive mechanism.

Description

Technical Field

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[0001] The present invention relates to an X-ray fluoroscopic imaging apparatus for performing X-ray imaging of a subject.

Background Art

[0002] Devices that display a fluoroscopic image of a subject on a monitor while taking a fluoroscopic image of the subject in an X-ray imaging apparatus are disclosed in Patent Documents 1 and 2.

[0003] In the X-ray imaging apparatus of Patent Document 1, an X-ray source and an X-ray detector are mounted on a rotatable C-arm. At the same time, a monitor is suspended from a ceiling rail, and the monitor is movable along the rail. Further, when controlling the position and orientation of the monitor, in order to eliminate the need for adjustment by manual operation of the operator, the position information of the operator is detected by a sensor, and based on the detection result, the position of the monitor is adjusted.

[0004] On the other hand, the X-ray fluoroscopic imaging apparatus of Patent Document 2 has a configuration in which a support column and a top plate on which a subject is placed are supported by a stand placed on the floor surface, and an X-ray generator is mounted at the upper end of the support column. The support column is movable in the longitudinal direction of the top plate and is structured to be tiltable with respect to the top plate. Further, the top plate is capable of tilting from a state horizontal to the floor surface to a vertical state. An arm for supporting a monitor is attached to the upper surface of the stand.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the X-ray imaging apparatus described in Patent Document 1, the operator's position is detected by a sensor, and the monitor's position is adjusted to match the operator's position, but it does not have a function to prevent contact between the C-arm and the monitor.

[0007] On the other hand, the X-ray fluoroscopy apparatus described in Patent Document 2 does not have a function to avoid contact between the monitor and the X-ray imaging unit.

[0008] The present invention aims to provide an X-ray imaging apparatus that can avoid contact with the X-ray imaging unit when moving the monitor. [Means for solving the problem]

[0009] One aspect of the present disclosure provides an X-ray imaging apparatus having an X-ray imaging unit, a monitor for displaying images, a monitor arm for supporting the monitor, and a processor. The X-ray imaging unit includes an X-ray generator for irradiating a subject with X-rays and an X-ray imaging unit drive mechanism for moving the X-ray generator. The monitor arm includes an arm mechanism for movably supporting the monitor and a brake for stopping the movement of the arm mechanism. The processor receives the amount of movement of the monitor from the arm mechanism and the amount of movement of the X-ray generator from the drive control unit, determines the distance between the monitor and the X-ray imaging unit, and if the distance is smaller than a predetermined reference distance, operates the brake to stop the movement of the monitor arm. [Effects of the Invention]

[0010] According to the present invention, it is possible to avoid contact with the X-ray imaging unit when moving the monitor. [Brief explanation of the drawing]

[0011] [Figure 1] A block diagram showing the overall configuration of an X-ray imaging apparatus according to Embodiment 1 of the present invention. [Figure 2] A top view showing the distance d between the monitor 132 and the X-ray generator 113 of the X-ray imaging apparatus of Embodiment 1. [Figure 3]Perspective view of the monitor arm 131 of the X-ray imaging apparatus according to Embodiment 1. [Figure 4] Perspective view of the X-ray imaging unit 1 of the X-ray imaging apparatus according to Embodiment 1. [Figure 5] Block diagram of the X-ray imaging unit drive mechanism section 220 of the X-ray imaging apparatus according to Embodiment 1. [Figure 6] Flowchart showing the operation of the processor 117 of the X-ray imaging apparatus according to Embodiment 1. [Figure 7] Diagram for explaining the distance d between the monitor 132 and the X-ray generator 113 of the X-ray imaging apparatus according to Embodiment 1. [Figure 8] Diagram for explaining the distance d between the monitor 132 and the X-ray generator 113 when the tilting mechanism tilts the support column 112 in the X-ray imaging apparatus according to Embodiment 1. [Figure 9] Diagram for explaining the distance d between the monitor 132 and the top plate 110 when the lifting mechanism raises the top plate in the X-ray imaging apparatus according to Embodiment 1. [Figure 10] Diagram for explaining the distance d' between the monitor 132 and the X-ray generator 113 when the tilting mechanism tilts the top plate and the X-ray generator 113 in the X-ray imaging apparatus according to Embodiment 2. [Figure 11] Flowchart showing the operation of the processor 117 of the X-ray imaging apparatus according to Embodiment 2. [Figure 12] Perspective view showing two types of brakes 150-1 and 150-2 arranged at the joint part in the X-ray imaging apparatus according to Embodiment 3. [Figure 13] Flowchart showing the operation of the processor 117 of the X-ray imaging apparatus according to Embodiment 3. [Figure 14] Flowchart showing the operation of the processor 117 of the X-ray imaging apparatus according to Embodiment 4.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0013] <<Embodiment 1>> The X-ray imaging apparatus 100 according to Embodiment 1 of the present invention will be described.

[0014] FIG. 1 is a diagram showing an overall overview of the X-ray imaging apparatus 100. FIG. 2 is a top view of the X-ray imaging apparatus 100. FIG. 3 is a perspective view showing the monitor arm 131.

[0015] The X-ray imaging apparatus 100 according to Embodiment 1 includes an X-ray imaging unit 1 and a monitor 132 for displaying an image. The monitor 132 is supported by a monitor arm 131. The X-ray imaging apparatus 100 also includes a processor 117 for controlling the monitor arm 131.

[0016] The X-ray imaging unit 1 includes an X-ray generator 113 for irradiating an object 101 with X-rays and an X-ray imaging unit drive mechanism unit 220 (see FIG. 5) for moving the X-ray generator 113. Details of the structural example of the X-ray imaging unit 1 will be described later.

[0017] The monitor arm 131 includes an arm mechanism unit 130 for movably supporting the monitor 132 and a brake 150 for stopping the operation of the arm mechanism unit. The monitor 132 is attached to the tip of the monitor arm 131. The base of the monitor arm 131 can be installed on the stand 121 of the X-ray imaging unit 1 by an installation unit 140. Also, the base of the monitor arm 131 can be installed on the ceiling or the floor surface of the room where the X-ray imaging unit 1 is arranged.

[0018] The arm mechanism 130 has a structure in which multiple rod-shaped arm members 144, 145 are rotatably connected by joints 141, 142, 143. Here, the arm members 144, 145 are straight rods and there are two of them. The joints 141, 142, 143 are located at the connection point between arm member 145 and the monitor 132, the connection point between arm member 144 and arm member 145, and the connection point between arm member 144 and the mounting part 140. The joints 141, 142, 143 are structured to be rotatable around at least one axis (two axes in this case). For example, each of the multiple joints 141 to 143 is structured to rotate around an axis perpendicular to the floor and an axis parallel to the floor. Furthermore, the arm members 144 and 145 that make up the monitor arm 131 are not limited to two, and the number of joints 141, 142, and 143 may be more or less than three.

[0019] The joints 141, 142, and 143 are equipped with potentiometers 141a, 142a, and 143a, respectively, which are sensors for detecting the rotation angle of the rotatable axis.

[0020] A handle 133 is attached to the monitor 132 as shown in Figures 1 and 3. The handle 133 is equipped with a release button 134 for releasing the brake 150 of the monitor arm 131 and an indicator lamp that shows the on / off status of the brake 150. When the operator releases the release button 134, the brake 150 is turned off (brake released). By releasing the brake by operating the release button 134, the operator can grasp the handle 133 and pull or push it. When the operator pulls or pushes the handle 133, the joints 141, 142, and 143 of the monitor arm 131 rotate, changing the orientation of the arm members 144 and 145 of the monitor arm 131, so that the monitor 132 can be moved to the desired location.

[0021] The processor 117 captures the moving amount of the monitor 132 from the arm mechanism unit 130 and the moving amount of the X-ray generator 113 from the X-ray imaging unit drive mechanism unit 220. The processor 117 calculates the distance d between the monitor 132 and the X-ray generator 113. When the distance d is smaller than a predetermined reference distance D, the brakes 150 of the joint parts 141, 142, 143 are operated to stop the movement of the monitor 132. Thereby, since the monitor 132 does not approach the X-ray generator 113 to a distance closer than the reference distance D, it is possible to prevent the monitor 132 from colliding with the X-ray generator 113.

[0022] It is also possible to arrange a drive unit such as a motor inside the joint parts 141 to 143 and operate the drive unit under the control of the control unit 118.

[0023] <Configuration of the X-ray imaging unit 1> Here, the X-ray imaging unit 1 will be described. In the present embodiment, the X-ray imaging unit 1 is a fluoroscopic imaging table.

[0024] FIG. 4 is a perspective view of the X-ray imaging unit 1 with the monitor 132 and the monitor arm 131 of the X-ray imaging apparatus 100 removed. FIG. 5 is a diagram showing the drive mechanism of the X-ray imaging unit 1.

[0025] As shown in FIG. 4, the X-ray imaging unit 1 includes a stand 121 placed on the floor surface, a support column support arm 20 protruding horizontally in the x-axis direction from one side surface of the stand 121 to the floor surface, a support column 112 mounted on the support column support arm 20, a support frame 30 supported at the tip of the support column support arm 20, an X-ray support arm 90 mounted on the upper end of the support column 112, and an X-ray generator 113 supported by the X-ray support arm 90.

[0026] A top plate 110 for mounting the subject 101 is supported on the support frame 30. The long axis direction of the top plate 110 is orthogonal to the x-axis. Inside the support frame 30, an X-ray detector 111 such as a Flat Panel Detector (FPD) is arranged.

[0027] The X-ray generator 113 is supported by an X-ray support arm 90, spaced apart from the top plate 110. The X-ray generator 113 has a built-in X-ray tube and generates X-rays from the X-ray tube by receiving power from a high-voltage generator 115. The X-ray generator 113 is fitted with an X-ray movable diaphragm 114 that limits the irradiation range of the X-rays. Inside the X-ray movable diaphragm 114 are built-in X-ray filters that selectively transmit X-rays of a specific energy.

[0028] X-rays generated from the X-ray generator 113 are irradiated onto the subject 101 mounted on the top plate 110, and the X-rays that pass through the subject 101 are detected by the X-ray detector 111.

[0029] The support arm 20 has an oblique insertion mechanism 224 mounted on its upper surface between the stand 121 and the support frame 30, and the lower end of the support column 112 is mounted on the oblique insertion mechanism 224. Inside the oblique insertion mechanism 224 is a mechanism that rotates the lower end of the support column 112 (in the direction of arrow A6). As a result, the central axis of the support column 112 rotates around a rotation axis parallel to the x-axis and tilts with respect to the normal of the top plate 110. Therefore, the X-ray generator 113 causes X-rays to be incident on the X-ray detector 111 from an oblique direction (hereinafter also referred to as oblique insertion).

[0030] Meanwhile, the stand 121 incorporates a lifting mechanism 221 that raises and lowers the support arm 20 (in the direction of arrow A1), and a tilting mechanism 222 that rotates the support arm 20 around its central axis (parallel to the x-axis) (referred to as tilting: in the direction of arrow A2). The lifting mechanism 221 and the tilting mechanism 222 raise and lower (in the direction of arrow A1) and tilt (in the direction of arrow A2) respectively while maintaining the relative position of the X-ray generator 113 and the top plate 110.

[0031] Between the lower end of the support column 112 and the oblique insertion mechanism 224, a support column x-direction sliding mechanism 51m is positioned to slide the lower end of the support column 112 in a direction parallel to the x-axis direction (arrow A4 direction).

[0032] Furthermore, an X-ray generator x-direction sliding mechanism 52m (X-ray generator sliding mechanism) 52m is positioned between the upper end of the support column 112 and the X-ray support arm 90, which slides the X-ray generator 113 in the x-direction by sliding the X-ray support arm 90 in a direction parallel to the x-axis direction with respect to the upper end of the support column 112 (direction of arrow A5).

[0033] Furthermore, between the upper end of the support column 112 and the X-ray support arm 90, there is a variable SID mechanism 225 (see Figure 5, not shown in Figure 4) that adjusts the distance (SID) between the X-ray generator 113 and the X-ray detector 111 by moving the X-ray support arm 90 in a direction along the central axis of the support column 112 (direction of arrow A10).

[0034] The column x-direction sliding mechanism 51m slides the entire column 112 parallel to the x-axis direction (arrow A4 direction). The X-ray generator x-direction sliding mechanism 52m slides the X-ray support arm 90, to which the X-ray generator 113 is connected, parallel to the x-axis direction relative to the column 112 (arrow A5 direction).

[0035] Furthermore, an X-ray generator rotation mechanism 226 (see Figure 5, not shown in Figure 4) is positioned at the connection between the X-ray support arm 90 and the X-ray generator 113. The X-ray generator rotation mechanism 226 rotates the X-ray generator 113 around an axis parallel to the y-axis (direction of arrow A9). Although not specifically shown, the X-ray generator 113 may also be configured to rotate around an axis parallel to the x-axis.

[0036] Furthermore, the support column 112 incorporates a support column y-direction sliding mechanism 223 (see Figure 3) that moves the support column 112 in the longitudinal direction of the top plate 110 (direction of arrow A3). The support column y-direction sliding mechanism 223 moves the support column 112 in the longitudinal direction of the top plate (direction of arrow A3) while maintaining the inclination angle of the support column 112 toward the top plate 110.

[0037] Furthermore, the support frame 30 incorporates a detector sliding mechanism 227 that slides the X-ray detector 111 in the short axis direction (arrow A7 direction: parallel to the x-axis) and the long axis direction (arrow A8 direction: parallel to the y-axis) of the top plate 110.

[0038] Furthermore, as shown in Figure 1, the X-ray imaging unit 1 is connected to an image processing unit 116 that generates an image from the X-ray signal output from the X-ray detector 111, a processor 117, a control unit 118 that controls the operation of the drive mechanisms (51m, 52m, 221~227), a display device 119 that displays images, etc., and an operation unit 120 that receives settings for imaging conditions, etc., from the operator. The control unit 118 operates the drive mechanisms (51m, 52m, 221~226), causing each part of the X-ray imaging unit 1 to move in the directions of arrows A1~A10.

[0039] <Processing by processor 117>

[0040] In this embodiment, each process performed by the processor 117 is executed on any computer. Alternatively, any computer may perform these processes using a processor as hardware, a program as software, or a combination thereof. In that case, the processor is configured to work in cooperation with the program to perform the various processes in this embodiment, and can function as a unit or means in this embodiment. Furthermore, the execution order of the processes by the processor is not limited to the order described and may be changed as appropriate. Any computer may be a general-purpose computer, a computer designed for a specific purpose, a workstation, or any other system capable of performing the processes.

[0041] A processor may consist of one or more hardware components, and the type of hardware is not limited. For example, a processor may consist of a CPU (Central Processing Unit), an MPU (Micro Processing Unit), a programmable logic device such as an FPGA (Field Programmable Gate Array), a dedicated circuit for executing a specific process such as an ASIC (Application Specific Integrated Circuit), a GPU (Graphic Processing Unit), or an NPU (Neural Processing Unit). Furthermore, the type of hardware may be a combination of different types of hardware. When multiple hardware components are configured to execute one or more processes of a processor, these components may reside in physically separate devices or in the same device. Also, in any embodiment, the order of each process performed by the processor is not limited to the order described above and may be changed as appropriate. Hardware is composed of electrical circuits (circuitry) that combine circuit elements such as semiconductor elements.

[0042] Furthermore, the program may be firmware or software such as microcode. Alternatively, the program may be, for example, a set of program modules, each function of which may be implemented by a processor configured to perform its respective function. The program may be program code or multiple code segments stored on one or more non-temporary computer-readable media (e.g., storage media or other storage). The program may be divided and stored on multiple non-temporary computer-readable media located on physically separate devices. Program code or code segments may represent any combination of procedures, functions, subprograms, routines, subroutines, modules, software packages, classes, or instructions, data structures, or program statements. Program code or code segments may be connected to other code segments or hardware circuits by sending and receiving information, data, arguments, parameters, or memory contents.

[0043] The processing of processor 117 will be explained in detail using the flow chart in Figure 6. In the following explanation, as shown in Figure 7, the short side of the top plate 110 is defined as the x-axis, the long side as the y-axis, and the direction perpendicular to the floor as the z-axis. The end 110a of the top plate 110 is defined as the reference position d0.

[0044] <Step S101> The processor 117 acquires the rotation angles α1, α2, α3 for the rotation axis parallel to the floor (y-axis) and the rotation angles β1, β2, β3 for the rotation axis perpendicular to the floor (z-axis) of each joint 141 to 143 by taking the output of potentiometers 141a, 142a, 143a built into the joints 141 to 143 of the monitor arm 131.

[0045] <Step S102> Next, the processor 117 obtains the current drive amount of the drive mechanism (51m, 52m, 221, 223~226) of the X-ray imaging unit 1 from the control unit 118.

[0046] <Step S103> As shown in Figure 7, the processor 117 determines the distance db between the end of the X-ray generator 113 of the X-ray imaging unit 1 closest to the monitor 132 and the reference position d0 (the end 110a of the top plate 110).

[0047] For example, if the column y-direction sliding mechanism 223 moves the column 112 in the direction of arrow A3 (y-axis direction) in Figure 4, the processor 117 calculates the distance dc in the y-axis direction from a predetermined reference position d0 (end 110a of the top plate 110) to the central axis 112a of the column 112 (central axis of the X-ray generator 113) from the amount of drive of the column y-direction sliding mechanism 223 acquired in step S102.

[0048] Next, the processor 117 calculates the distance db from the reference position d0 to the end 113a of the X-ray generator 113 by subtracting the previously determined distance L between the central axis 112a of the support column 112 and the end 113a of the X-ray generator 113 on the side closer to the monitor 132 from the distance dc (db = dc - L).

[0049] <Step S104> Next, the processor 117 determines the distance da from the X-ray generator 113 side end 132a of the monitor 132 to the reference position d0.

[0050] Specifically, the processor 117 calculates, as shown in Figure 2, the angles θ1 and θ2 of the arm members 144 and 145 with respect to the y-axis, the angle θ3 of the main plane of the monitor 132 with respect to the y-axis, and the lengths of the arm members 144 and 145 in the xy-plane parallel to the floor, based on the amount of rotation (rotation angle) of each joint 141 to 143 acquired in step S101 with respect to the rotation axis parallel to the floor. From the angles θ1 and θ2 and the lengths of the arm members 144 and 145 in the xy-plane, the processor 117 calculates the distance dp in the y-axis direction between joint 141 and joint 143 (see Figure 2). Furthermore, the processor 117 assigns a negative sign to the distance dp if the center of the joint 143 is located closer to the reference position d0 (end 110a) of the top plate 110 than the center of the joint 141, and assigns a positive sign to the distance dp if the center of the joint 143 is located further from the reference position d0 than the joint 141.

[0051] Furthermore, based on the angle θ3 and the previously determined width of the monitor 132, the distance dq between the joint 143 and the end 132a of the monitor 132 on the X-ray generator 113 side is calculated (see Figure 2).

[0052] The processor 117 calculates the distance da in the y-axis direction of the end 132a of the X-ray imaging unit 1 on the X-ray generator 113 side of the monitor 132 relative to the reference position d0, based on the previously determined distance dr between the end 110a of the top plate 110 and the joint 141, the calculated distance dp, and the distance dq (da = dr + dp + dq).

[0053] <Step S105> The processor 117 uses the distances db and da obtained in steps S104 and S105 to determine the distance d (see Figure 7) in the y-axis direction between the monitor 132 and the X-ray generator 113. d=db-ba It is calculated by [method].

[0054] <Steps S106, S107> The processor 117 determines whether the unlock button 134 on the handle 133 of the monitor 132 is pressed (on) by the operator (step S106). If the unlock button 134 is on, the lock is released, so the process proceeds to step S107, where the brakes 150 of the joints 141, 142, and 143 are all turned off, and the indicator lamp on the handle 133 is turned off to indicate that the brakes 150 are off, before returning to step S101 (step S107).

[0055] On the other hand, if the unlock button 134 is not turned on (not unlocked) in step S106, the process proceeds to step S108.

[0056] <Steps S108, S109> In step S108, the processor 117 determines whether the distance d between the monitor 132 and the X-ray generator 113, calculated in step S105, is smaller than a predetermined reference distance D. If the distance d is greater than or equal to the reference distance D, the process returns to step S101 (step S108).

[0057] On the other hand, if in step S108 the distance d is smaller than the reference distance D, the processor 117 proceeds to step S109, turns on all the brakes 150 of the joints 141, 142, and 143, and illuminates the indicator lamp on the handle 133 to indicate that the brakes 150 are on, and then returns to step S101 (step S109).

[0058] As a result, the rotation of the joints 141, 142, and 143 of the monitor arm 131 is stopped by the brake 150, so even if the operator pushes or pulls the handle 133, the monitor 132 cannot move. Therefore, the monitor 132 does not come closer to the X-ray generator 113 than the reference distance D, and it is possible to prevent the monitor 132 from colliding with the X-ray generator 113.

[0059] In the flow of FIG. 6, in steps S101 to S105, an example of calculating the distance d between the monitor 132 and the X-ray generator 113 by calculation has been described. However, for each combination of the angles of the joint portions 141 to 143 and for each combination of the driving amounts of the drive mechanisms (51m, 52m, 221, 223 to 226) of the X-ray imaging unit 1, the distance d may be calculated in advance and stored in a memory or the like built in the processor 117 in the form of a table or the like. Thereby, without performing the calculations in steps S103 to S105, in step S106, the distance d corresponding to the combination of the rotation angle and the driving amount obtained in steps S101 and S102 can be obtained by referring to the table.

[0060] In the present embodiment, the processor 117 calculates the distance between the X-ray generator 113 and the monitor 132. However, when the X-ray movable aperture 114 or the support column 112 is closer to the monitor 132, the distance between the X-ray movable aperture 114 or the support column 112 and the monitor 132 may be calculated as the distance d.

[0061] <Inclination of the X-ray generator 113> In the example of FIG. 7 described above, only the movement of the X-ray generator 113 of the X-ray imaging unit 1 in the y-axis direction (the longitudinal direction of the top plate 110) is considered, and the distance d between the monitor 132 and the X-ray generator 113 is calculated in the y-axis direction. However, the X-ray generator 113 can be inclined as shown in FIG. 8 by the oblique insertion mechanism 224. In this case, the X-ray generator 113 and the monitor 132 approach each other in the y-axis direction more than when they are not inclined. Therefore, when the processor 117 grasps that the oblique insertion mechanism 224 is inclining the support column 112 by the driving amount obtained in step S102, in step S103, the processor 117 calculates the distance d in consideration of the inclination of the support column 112 of the X-ray generator 113.

[0062] Specifically, in step S103, the processor 117 calculates the angle θ4 of the central axis of the support column 112 with respect to the vertical direction (z-axis direction) (see Figure 8). Also, similar to step S103 in Figure 6, the processor 117 calculates the distance db of the end 113a of the X-ray generator 113 when the support column 112 is not tilted. Furthermore, using the angle θ4 and the length L of the X-ray generator 113, the processor 117 calculates the distance W that the X-ray generator 113 approaches the monitor 132 when the X-ray generator 113 is tilted at an angle θ4.

[0063] The processor 117 calculates the distance db' of the end 113a of the X-ray generator 113 closest to the monitor 132 by subtracting the distance w due to the slope from the distance db obtained in step S103 of Figure 6.

[0064] The processor 117 uses the distances db' and da obtained in steps S104 and S105 to determine the distance d between the monitor 132 and the X-ray generator 113. d=db'-ba It is calculated by [method].

[0065] From step S106 onward, the process is the same as the flow shown in Figure 6. This allows the processor 117 to calculate the distance d between the monitor 132 and the X-ray generator 113, even if the support column 112 of the X-ray generator 113 is tilted. If the calculated distance d is smaller than the reference distance D, the brake 150 can be activated to stop the movement of the monitor 132.

[0066] <Height adjustment of the tabletop (110cm)> In the X-ray imaging apparatus 100, when the top plate 110 is raised and the monitor 132 is lowered by the operation of the drive mechanism (lifting mechanism 221) of the X-ray imaging unit 1, as shown in Figure 9, the monitor 132 approaches the top plate 110 in the vertical direction (z-axis direction).

[0067] In this case, if the processor 117 obtains in step S102 that the lifting mechanism 221 is raising the top plate 110, it is configured to calculate not only the distance d in the y-axis direction, but also the vertical distance d between the lower end 132b of the monitor 132 and the upper surface 110b of the top plate 110 in steps S103 to S105.

[0068] Specifically, in step S103, the processor 117 calculates the distance ds between the top surface 110b of the top plate 110 and the floor surface dB from the drive amount of the lifting mechanism 221.

[0069] Furthermore, in step S104, the processor 117 calculates the distance dt between the lower end 132b of the monitor 132 and the floor surface dB based on the rotation angles of the joints 141 to 143, the lengths of the arm members 144 and 145, the height dimensions of the monitor 132, and the height information of the stand 121.

[0070] In step S105, the processor 117 uses the distances ds and dt obtained in steps S104 and S105 to determine the vertical distance d between the monitor 132 and the X-ray generator 113 in the z-axis direction. d = dt - bs It is calculated by [method].

[0071] From step S106 onward, the flow is the same as in Figure 6. This allows the system to calculate the distance d between the monitor 132 and the top plate 110 when the top plate 110 is raised, and if the distance d is smaller than the reference distance D, activate the brake 150 to stop the movement of the monitor 132.

[0072] <Tilt of tabletop 110> As shown in Figures 10(a) and (b), when the top plate 110 is rotated (tilted) in the direction of arrow A2 in Figure 4 by the tilting mechanism 222, the distance d in the y-axis direction between the X-ray generator 113 and the monitor arm 131 may be a different distance d than the distance d when the top plate is not tilted.

[0073] The processor 117 takes into account the rotation (tilting) of the top plate 110 by the tilting mechanism 222 and calculates the distance d between the monitor 132 and the X-ray generator 113.

[0074] Specifically, the processor 117 first performs steps S101 to S105 in the same way as when the top plate 110 is not tilted, and the distance d in the y-axis direction between the monitor 132 and the X-ray generator 113 (see Figure 10(a)) d=db-ba It is calculated by [method].

[0075] Next, the processor 117 determines whether the tilting mechanism 222 is rotating (tilting) the top plate 110 based on the amount of drive of the tilting mechanism 222 obtained in step S102. If the top plate 110 is being tilted, the processor corrects the distance d calculated in step S105 to a distance (d') that takes into account the rotation of the top plate 110 (see Figure 10(b)).

[0076] Specifically, the processor 117 calculates the angle θ5 of the central axis of the support column 112 relative to the vertical direction (z-axis direction) (see Figure 10(b)) based on the amount of drive of the tilting mechanism 222. Furthermore, the processor 117 uses the angle θ5 and the length L of the support column 112 of the X-ray generator 113 to calculate the distance Q at which the X-ray generator 113 approaches the monitor 132 due to the tilt of the top plate 110.

[0077] The processor 117 calculates the corrected distance d' by subtracting the distance Q due to the slope from the distance d obtained in step S105 as shown in the following formula.

[0078] d'=dQ From step S106 onward, the flow is the same as in Figure 6. This allows the system to calculate the distance d' between the monitor 132 and the top plate 110 if the top plate 110 is tilted, and if the distance d' is smaller than the reference distance D, activate the brake 150 to stop the movement of the monitor 132.

[0079] As described above, in the X-ray imaging apparatus of Embodiment 1, when moving the monitor 132, the distance to the X-ray generator 113 and the distance to the tabletop 110 are calculated, and if either is smaller than a predetermined distance D, the brake 150 is activated to stop the movement of the monitor 132. This makes it possible to automatically avoid the monitor 132 coming into contact with the X-ray generator 113 or the tabletop 110.

[0080] In Embodiment 1, the distance between the monitor 132 and the X-ray generator 113, and the distance between the monitor 132 and the tabletop 110 are calculated. However, the monitor arm 131 may be closer to the X-ray generator 113 or the tabletop 110 than the monitor 132. Therefore, it is also possible to further calculate the distance d between the monitor arm 131 and the X-ray generator 113 or the tabletop 110, and configure the system to activate the brake 150 if the distance d is smaller than the reference distance D. In this case, in step S104, the processor 117 calculates the positions of each joint 141, 142, and 143 of the monitor arm 131 from the rotation angles of the joints 141, 142, and 143. Furthermore, as shown in Figure 10(b), it is also possible to tilt the support column 112 relative to the top plate 110 using the inclined insertion mechanism 224, while tilting the top plate 110 using the tilting mechanism 222, as shown in Figure 8. In that case, the distance d can be calculated by combining the method for calculating distance d explained using Figure 8 and the method for calculating distance d explained using Figure 10(b).

[0081] <<Embodiment 2>> The X-ray imaging apparatus of Embodiment 2 will be described with reference to Figure 11.

[0082] The X-ray imaging apparatus of Embodiment 2 has the same configuration as Embodiment 1, but in step S108, even if the distance d between the monitor 132 and the X-ray generator 113 is smaller than the reference distance D, if the time change of the calculated distance d indicates that the distance d is increasing (in the direction that the monitor 132 moves away from the X-ray generator 113), the brake 150 is not turned on.

[0083] The operation of the X-ray imaging apparatus of Embodiment 2 will be explained using the flowchart in Figure 11. In the flowchart in Figure 11, steps S101 to S109 perform the same processing as steps S101 to S109 in the flowchart in Figure 6, and are denoted by the same reference numerals. Steps S99, S100, and S110 have been newly added to the flowchart in Figure 11.

[0084] (Step S99) In the flow shown in Figure 11, the processor 117, as step S99, executes the processes of steps S101 to S105 in Figure 6 and calculates the distance d in the y-axis direction between the monitor 132 and the X-ray generator 113 (see Figure 7).

[0085] (Step S100) The processor 117 assigns the value of distance d calculated in step S99 to the distance dp in the memory of the processor 117 and stores it.

[0086] (Steps S101-S107) The processor 117 executes steps S101 to S105 in Figure 6 and calculates the distance d in the y-axis direction between the monitor 132 and the X-ray generator 113 (see Figure 7). Then, it proceeds to step S106 to determine whether the unlock button is on (step S106). If the unlock button 134 is on, it proceeds to step S107, where it turns off all the brakes 150 of the joints 141, 142, and 143, and turns off the indicator lamp on the handle 133 to indicate that the brakes 150 are off, and then returns to step S100. On the other hand, if the unlock button 134 is not turned on (the lock is not released) in step S106, the process proceeds to step S108. (Step S108) The processor 117 determines whether the distance d between the monitor 132 and the X-ray generator 113, calculated in step S105, is smaller than the reference distance D. If the distance d is smaller than the reference distance D, the process proceeds to step S110. (Steps S110, S109) The processor 117 reads the distance dp value stored in memory in step S100, compares it with the distance d calculated in step S105, and determines whether distance d is smaller than distance dp (step S110). If distance d is smaller than distance dp, the movement is changing in the direction that distance d decreases (the direction in which the monitor 132 approaches the X-ray generator 113), so the process proceeds to step S109, where the brakes 150 on the joints 141, 142, and 143 are all turned on, stopping the movement of the monitor 132. The indicator lamp on the handle 133 is also turned on to show the operator that the brakes 150 are on, and the process returns to step S100. In step S100, the processor 117 stores the value of distance d calculated in step S106 by substituting it into the distance dp in the memory of the processor 117, and then repeats steps S101 and below. On the other hand, in step S108 above, if distance d is greater than or equal to the reference distance D, the brake 150 is not turned on, and the process returns to step S100. Furthermore, in step S110, if the distance d is greater than or equal to the previous distance dp, the distance d is increasing (the monitor 132 is moving away from the X-ray generator 113), so the brake 150 is not turned on and the process returns to step S100.

[0087] Thus, in the X-ray imaging apparatus of Embodiment 2, even if the distance d between the monitor 132 and the X-ray generator 113 is smaller than the reference distance D, if the time change of the distance d indicates that the distance d is increasing (the monitor 132 is moving away from the X-ray generator 113), there is no risk of the monitor 132 colliding with the X-ray generator 113, and therefore the brake 150 is not turned on. On the other hand, if the time change of the distance d is decreasing, the brake 150 is turned on.

[0088] Thus, in Embodiment 2, even if the distance d is smaller than the reference distance D, the brake 150 is not turned on if there is no risk of the monitor 132 colliding with the X-ray generator 113.

[0089] <<Embodiment 3>> The X-ray imaging apparatus of Embodiment 3 will be described with reference to Figures 12 and 13.

[0090] The brake 150 of the X-ray imaging apparatus in Embodiment 3 is configured to allow the braking force to be changed to at least two levels: strong and weak. Specifically, as shown in Figure 12 as an example, two or more brakes 150 are arranged at each of the joints 141, 142, and 143 of the arm mechanism 130. The processor 117 achieves a weak braking force by operating the second brake 150-2 of the two or more brakes 150. A strong braking force is achieved by operating both the first brake 150-1 and the second brake 150-2. Two types of reference distances D are used: a first reference distance D1 and a second reference distance D2 (D2 > D1). Note that if the braking force of the first brake 150-1 is greater than the braking force of the second brake 150-2, a strong braking force may be achieved by operating only the first brake.

[0091] Embodiment 3 will be explained in more detail using the flowchart in Figure 13.

[0092] (Steps S99~S107) Processor 117 performs steps S99 to S107 in the same manner as in Embodiment 2. In step S107, both brakes 150-1 and 150-2 are turned OFF.

[0093] (Steps S121, S110, S122) In step S121, the processor 117 determines whether the distance d between the monitor 132 and the X-ray generator 113, which was calculated in step S105, is smaller than the first reference distance D1. If it is smaller, the process proceeds to step S110.

[0094] In step S110, the distance dp stored in the memory of the processor 117 is read and compared with the calculated distance d to determine whether distance d is smaller than distance dp (step S110).

[0095] If distance d is greater than or equal to distance dp, it indicates that distance d is increasing (in the direction away from the X-ray generator 113), so brakes 150-1 and 150-2 are not turned on, and the process returns to step S100, where the value of distance d is assigned to distance dp in the memory of the processor 117 and stored.

[0096] On the other hand, in step S110, if the distance d between the monitor 132 and the X-ray generator 113 calculated this time is smaller than the previous distance dp, then the distance d is changing in the direction of decreasing (the direction in which the monitor 132 approaches the X-ray generator 113), so the process proceeds to step S122, where both brakes 150-1 and 150-2 are turned on to stop the movement of the monitor 132 with a strong braking force (step S122). In step S121 described above, if the distance d calculated this time is greater than or equal to the reference distance D1, proceed to step S123.

[0097] (Steps S123, S111, S124)

[0098] In step S123, the processor 117 determines whether the distance d is smaller than the second reference distance D2, and if it is smaller, proceeds to step S111.

[0099] In step S111, the distance dp stored in the memory of the processor 117 is read and compared with the distance d calculated this time to determine whether distance d is smaller than distance dp (step S111).

[0100] If distance d is greater than or equal to distance dp, it indicates that the direction in which distance d increases (the direction in which monitor 132 moves away from X-ray generator 113), so brake 150-2 is not turned on and the system returns to step S100.

[0101] On the other hand, if distance d is smaller than distance dp, the distance d is changing in the direction of decreasing distance d (the direction in which monitor 132 approaches X-ray generator 113), so the process proceeds to step S124, where only brake 150-2 is turned on, a weak braking force is applied to the movement of monitor 132, and the process returns to step S100 (step S124).

[0102] By performing this process, the processor 117 first turns on only brake 150-2 when it determines in step S123 that the distance d has become smaller than the second reference distance D2 (D2 > D1), thereby slowing the movement of monitor 132 with a weak braking force. Then, in step S121, when the distance d has become smaller than the first reference distance D1, it turns on both brakes 150-1 and 150-2, thereby stopping the movement of monitor 132 with a strong braking force.

[0103] As described above, in Embodiment 3, when the monitor 132 approaches the X-ray generator 113, the processor 117 first turns on only one brake 150-2 to apply a weak braking force, and then, when the monitor 132 approaches the X-ray generator 113, turns on two brakes 150-1 and 150-2 to apply a strong braking force, thereby stopping the monitor 132 in stages. Therefore, compared to the case where the processor 117 stops the monitor 132 with a single operation of the brake 150, as in Embodiments 1 and 2, the operator pushing and pulling the handle 133 can perceive that the monitor 132 stops smoothly, improving the comfort of operation.

[0104] Other configurations and operations of the X-ray imaging apparatus 100 in Embodiment 3 are the same as those in Embodiments 1 and 2, so their description will be omitted.

[0105] <<Embodiment 4>> The X-ray imaging apparatus of Embodiment 4 will be described with reference to Figure 14.

[0106] In the X-ray imaging apparatus of Embodiment 4, the processor 117 activates the brake 150 and then releases the brake 150 after a predetermined time (for example, 2 seconds) has elapsed.

[0107] As a result, even if the X-ray generator 113 approaches and collides with the monitor 132 due to the operation of the X-ray unit drive mechanism 220 of the X-ray imaging unit 1, the brake 150 of the monitor arm 131 is released, allowing the monitor 132 to be pushed backward by the X-ray generator 113. Therefore, damage to the monitor 132, monitor arm 131, and X-ray imaging unit 1 can be prevented.

[0108] This will be explained in more detail using the flow chart in Figure 14. In Figure 14, steps S99 to S107, S108, S110, and S109 are the same as the flow chart in Figure 11 of Embodiment 2. In the flow chart of Figure 14, steps S131 and S132 differ from the flow chart in Figure 11 of Embodiment 2.

[0109] (Steps S99~S107) Processor 117 executes steps S99 to S107 in the same manner as in Embodiment 2. If the unlock button is not turned on in step S106, proceed to step S131.

[0110] (Steps S131, S108, S110, S109) In step S131, the processor 117 determines whether the brake 150 is on. If it is not on, in step S108, it determines whether the distance d calculated in step S105 is smaller than the reference distance D. If it is smaller, the process proceeds to step S110.

[0111] In step S110, the distance dp stored in the memory of the processor 117 is read and compared with the distance d calculated this time to determine whether distance d is smaller than distance dp (step S110).

[0112] In step S110, if distance d is greater than or equal to the previous distance dp, it indicates that distance d is increasing (the monitor 132 is moving away from the X-ray generator 113). Therefore, the brake 150 is not turned on, and the process returns to step S100 to store the current distance d as distance dp in memory.

[0113] On the other hand, in step S110, if the distance d is smaller than the previous distance dp, the process proceeds to step S109, where the brake 150 is turned on and the movement of the monitor 132 is stopped. Also, the indicator lamp on the handle 133 is illuminated (step S109).

[0114] (Step S132) On the other hand, if the brake 150 is turned on in step S131 described above, the processor 117 proceeds to step S132.

[0115] In step S132, the processor 117 determines whether 2 seconds have elapsed since the brake 150 was turned on in step S110. If 2 seconds have elapsed since the brake 150 was turned on, the process proceeds to step S107, and the brake 150 is turned off. On the other hand, in step S132, if 2 seconds have not elapsed since the brake 150 was turned on in step S110, the processor 117 returns to step S100.

[0116] Thus, in Embodiment 4, the brake 150 of the monitor arm 131 is released after 2 seconds have elapsed since it was turned on. Therefore, even if the X-ray generator 113 approaches the monitor 132 and collides with it, the monitor 132 can be pushed back by the X-ray generator 113. Thus, damage to the monitor 132, monitor arm 131, and X-ray imaging unit 1 can be prevented. [Explanation of Symbols]

[0117] 1 X-ray imaging unit 20 Support arm for support column 30 support slots 51m support column x-direction sliding mechanism 52m X-ray generator x-direction sliding mechanism 52m drive mechanism 90 X-ray support arm 100 X-ray imaging equipment 101 Subjects 110 Top plate 110a end 110b Top side 111 X-ray detector 112 Post 112a Center axis 113 X-ray generator 113a End 115 High-voltage generator 116 Image Processing Unit 117 Processors 118 Control Unit 119 Display device 120 Operation section 121 Stand 130 Arm mechanism 131 Monitor Arm 132 monitors 132a End 132b bottom end 133 Handle 134 Unlock button 140 Installation section 141, 142, 143 Joints 141a, 142a, 143a potentiometers 144, 145 Arm members 150 Brake 150-1, 150-2 Brake 150-1 First Brake 150-2 Second brake 220 X-ray imaging unit drive mechanism 221 Lifting mechanism 222 Lifting mechanism 223 Column y-direction sliding mechanism 224 Oblique entry mechanism 225 SID Variable Mechanism 226 X-ray generator rotation mechanism 227 Detector slide mechanism

Claims

1. The system comprises an X-ray imaging unit, a monitor for displaying images, a monitor arm for supporting the monitor, and a processor. The X-ray imaging unit comprises an X-ray generator for irradiating the subject with X-rays, and at least an X-ray imaging unit drive mechanism for moving the X-ray generator. The monitor arm includes an arm mechanism that movably supports the monitor, and a brake that stops the movement of the arm mechanism. The X-ray imaging apparatus is characterized in that the processor acquires the amount of movement of the monitor from the arm mechanism and the amount of movement from the X-ray imaging unit drive mechanism, determines the distance between the monitor and the X-ray imaging unit, and if the distance is smaller than a predetermined reference distance, operates the brake to stop the movement of the monitor.

2. An X-ray imaging apparatus according to claim 1, wherein the processor does not operate the brake when the time change of the calculated distance is in the direction of increasing distance, even when the distance is smaller than the reference distance.

3. An X-ray imaging apparatus according to claim 1, wherein the brake is capable of changing its braking ability to at least two levels: strong and weak. The processor has a first reference distance which is greater than the first reference distance and a second reference distance which is smaller than the first reference distance. The X-ray imaging apparatus is characterized in that the processor operates the brake with a weak braking force when the calculated distance is less than the first reference distance between the monitor and the X-ray generator and greater than or equal to the second reference distance, and operates the brake with a strong braking force when the calculated distance is less than the second reference distance.

4. An X-ray imaging apparatus according to claim 1, wherein the processor releases the brake after a predetermined time has elapsed since the brake was activated.

5. An X-ray imaging apparatus according to claim 1, wherein the X-ray imaging unit further comprises a top plate on which a subject is mounted, The X-ray imaging unit drive mechanism includes a mechanism for moving the X-ray generator parallel to the main plane of the top plate, a mechanism for tilting the top plate relative to the main plane of the top plate, a lifting mechanism for raising and lowering the top plate, and a tilting mechanism for tilting the top plate. The X-ray imaging apparatus is characterized in that the processor determines the distance between the monitor and the X-ray generator, and the distance between the monitor and the tabletop, and operates the brake if either of these distances is smaller than the reference distance.

6. An X-ray imaging apparatus according to claim 3, wherein two or more brakes, including a first brake and a second brake, are arranged in the same arm mechanism, and the processor achieves a weak braking force by operating the first brake among the two or more brakes, and achieves a strong braking force by operating the second brake, or the first brake and the second brake.

7. An X-ray imaging apparatus according to claim 1, wherein the arm mechanism includes a plurality of rod-shaped arm members, a joint that connects the ends of two arm members so as to be rotatable about at least one axis, and a sensor that detects the rotation angle of the joint, The monitor is supported at the tip of one of the multiple rod-shaped arm members, The X-ray imaging apparatus is characterized in that the brake has a structure that stops the rotation of the joint.

8. An X-ray imaging apparatus according to claim 7, wherein the processor acquires the rotation angle of the joint from the sensor as the amount of movement of the monitor.

9. An X-ray imaging apparatus according to claim 1, wherein the X-ray imaging unit includes a stand, An X-ray imaging apparatus characterized in that the base of the monitor arm is attached to the top of the stand, and the tip of the monitor arm is to which the monitor is attached.

10. An X-ray imaging apparatus according to claim 1, characterized in that the base of the monitor arm is attached to the ceiling of the room in which the X-ray imaging unit is located, the monitor is attached to the tip of the monitor arm, and the monitor is suspended and supported from the ceiling by the monitor arm.

Images