JP2021142145A - X-ray computer tomographic apparatus - Google Patents

Abstract

To reduce noise by a fan in an examination room.SOLUTION: An X-ray computer tomographic apparatus according to the embodiment includes a fixed frame, a bearing, a first tube, and a second tube. The fixed frame supports a rotation frame to which an X-ray tube for generating an X-ray is attached so that it can rotate around a rotation shaft. The bearing includes a first ring provided to the rotation frame along a circumferential direction of the rotation frame and a second ring provided to the fixed frame facing the first ring, and assists the rotation of the rotation frame. The first tube is provided to the rotation frame along a circumferential direction of the first ring, and a first heat medium is injected into it. The second tube is provided to the fixed frame along a circumferential direction of the second ring, and a second heat medium is injected into it.SELECTED DRAWING: Figure 6

Description

The embodiments disclosed in this specification and drawings relate to an X-ray computed tomography apparatus.

Conventionally, a gantry (also referred to as a gantry) in an X-ray computed tomography apparatus rotatably supports an X-ray tube by a rotating frame. The X-ray tube generates heat when X-rays are generated. The heat generated in the X-ray tube is released to the inside of the gantry via a radiator installed in the rotating frame. The heat inside the gantry is released into the inspection room by a fan mounted on the ceiling of the gantry.

When the procedure is performed in the laboratory, the wind noise of the fan may interrupt the doctor's conversation about the procedure or make it difficult for the content of the conversation to be communicated to other doctors.

Japanese Unexamined Patent Publication No. 8-10248

One of the problems to be solved by the embodiments disclosed in the present specification and the drawings is to reduce the noise caused by the fan in the examination room. However, the problems to be solved by the embodiments disclosed in the present specification and the drawings are not limited to the above problems. It is also possible to position the problem corresponding to each effect of each configuration shown in the embodiment described later as another problem.

The X-ray computed tomography apparatus according to the present embodiment includes a fixed frame, bearings, a first tube, and a second tube. The fixed frame rotatably supports a rotating frame to which an X-ray tube that generates X-rays is attached around a rotation axis. The bearing has a first ring provided on the rotating frame along the circumferential direction of the rotating frame and a second ring provided on the fixed frame facing the first ring and of the rotating frame. Assists rotation. The first tube is provided in the rotating frame along the circumferential direction of the first ring, and the first heat medium is injected. The second tube is provided in the fixed frame along the circumferential direction of the second ring, and the second heat medium is injected.

FIG. 1 is a diagram showing a configuration example of an X-ray CT apparatus according to an embodiment. FIG. 2 is a diagram showing an example of an examination room, an operation room, and a power supply room regarding the arrangement of an X-ray CT apparatus according to an embodiment. FIG. 3 is a perspective view showing an example of a gantry device from which the exterior cover has been removed according to the embodiment. FIG. 4 is a view of the rotating frame viewed from the front side with respect to the rotating inner cooling pipe and the first ring connected to the X-ray tube according to the embodiment. FIG. 5 is a view of the gantry device as viewed from the back side according to the embodiment. FIG. 6 is a diagram showing an example of the positional relationship between the bearing, the rotating inner cooling pipe, the rotating outer cooling pipe, the X-ray tube, and the radiator when the gantry device is viewed from the side according to the embodiment. FIG. 7 is an enlarged view of a part of FIG. 6 according to the embodiment. FIG. 8 is a view of the rotating frame viewed from the front side with respect to the rotating inner cooling pipe and the first ring connected to the X-ray tube according to the modified example of the embodiment. FIG. 9 is an enlarged view of a part of FIG. 8 according to a modified example of the embodiment.

Hereinafter, embodiments of an X-ray computed tomography apparatus (hereinafter referred to as an X-ray CT (computed tomography) apparatus) will be described in detail with reference to the drawings. In the following embodiments, the parts with the same reference numerals perform the same operation, and duplicate description will be omitted as appropriate.

(Embodiment)
FIG. 1 is a diagram showing a configuration example of the X-ray CT apparatus 1 according to the present embodiment. As shown in FIG. 1, the X-ray CT device 1 includes, for example, a gantry device 10, a bed device 30, a console device 40, and a radiator 50. In the present embodiment, the rotation axis of the rotation frame 13 in the non-tilt state or the longitudinal direction of the top plate 33 of the sleeper device 30 is orthogonal to the Z-axis direction and the Z-axis direction, and is horizontal to the floor surface. Is orthogonal to the X-axis direction and the Z-axis direction, and the axial direction perpendicular to the floor surface is defined as the Y-axis direction, respectively. In FIG. 1, a plurality of gantry devices 10 are drawn for convenience of explanation, but in the actual configuration of the X-ray CT device 1, the gantry device 10 is one.

FIG. 2 is a diagram showing an example of an examination room, an operation room, and a power supply room regarding the arrangement of the X-ray CT apparatus 1. As shown in FIG. 2, the gantry device 10 and the sleeper device 30 are arranged in the examination room SR. A console device 40 is arranged in the control room OR. Further, a radiator 50 is arranged in the power supply room PR. In the power supply room PR, a server that executes various processes such as a pre-processing function 442, a reconstruction processing function 443, and an image processing function in the console device 40 may be installed. Further, in the power supply room PR, a distribution board, a power distributor, and the like for supplying power to the X-ray CT apparatus 1 are installed.

The gantry device 10 and the bed device 30 operate based on an operation from the user via the console device 40, or an operation from the user via the gantry device 10 or the operation unit provided in the bed device 30. The gantry device 10, the sleeper device 30, and the console device 40 are connected to each other by wire or wirelessly so as to be able to communicate with each other.

FIG. 3 is a perspective view showing an example of the gantry device 10 from which the exterior cover has been removed. The gantry device 10 is a device having an imaging system that irradiates the subject P with X-rays and collects projection data from the detection data of the X-rays transmitted through the subject P. As shown in FIGS. 1 and 3, the gantry device 10 includes a fixed frame 5, a pair of erection frames 6, a base stand 7, two gantry arms 8, and an X-ray tube 11 (X-ray generator). An X-ray detector 12, a rotating frame 13, a bearing 14, an in-rotating cooling tube (first tube) 15, an extra-rotating cooling tube (second tube) 16, and an X-ray high-voltage device 17. A control device 18, a wedge 19, a collimator 20, and a DAS (Data Acquisition System) 21.

As shown in FIG. 3, the fixed frame 5 rotatably supports the rotating frame 13 around the rotation axis R1. The fixed frame 5 is a metal frame formed of a metal such as aluminum and having an opening (bore) formed in the center. The fixed frame 5 rotatably supports the rotating frame 13 around the rotating shaft R1 (Z axis) via a bearing (hereinafter referred to as a support bearing). A pair of upright frames 6 are attached to both side surfaces of the fixed frame 5 via a gantry arm 8.

A base stand 7 is attached to the other end side of the pair of standing frames 6. A pair of upright frames 6 are provided upright on the base stand 7. The base stand 7 is installed on the floor surface of the examination room SR. The base stand 7 supports the fixed frame 5 away from the floor surface via the erection frame 6. The base stand 7 is made of a metal such as aluminum.

The two gantry arms 8 support the fixed frame 5 so as to be tiltable around the horizontal axis (X axis) R2 orthogonal to the rotation axis R1 and parallel to the floor surface. Each gantry arm 8 is attached to the upper part of the base stand 7 and connects the base stand 7 and the fixed frame 5. Due to the tilt of the fixed frame 5, the vertical axis R3 orthogonal to the rotation axis R1 and the horizontal axis R2 is tilted with respect to the floor surface. The gantry arm 8 tilts the fixed frame 5 in response to a drive signal supplied from a drive device (not shown). The gantry arm 8 is made of a metal such as aluminum. The side on which the X-ray tube 11 or the like is attached to the rotating frame 13 is referred to as the front side, and the fixed frame 5 side is referred to as the back side.

The X-ray tube 11 is a vacuum tube that generates X-rays by irradiating thermoelectrons from the cathode (filament) toward the anode (target) by applying a high voltage from the X-ray high voltage device 17 and supplying a filament current. Is. X-rays are generated when thermions collide with the target. The X-rays generated at the bulb focal point in the X-ray tube 11 are formed into a cone beam shape through, for example, a collimator 20, and are irradiated to the subject P. For example, the X-ray tube 11 includes a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermoelectrons. In the present embodiment, the so-called multi-tube type X in which a plurality of pairs of the X-ray tube 11 and the X-ray detector 12 are mounted on the rotating frame 13 also in the one-tube type X-ray CT apparatus. It can also be applied to a line CT device.

The X-ray detector 12 detects X-rays irradiated from the X-ray tube 11 and passed through the subject P, and outputs an electric signal corresponding to the X-ray dose to the DAS 21. The X-ray detector 12 has, for example, a plurality of detection element sequences in which a plurality of detection elements are arranged in the channel direction along one arc centering on the focal point of the X-ray tube 11. The X-ray detector 12 has, for example, a structure in which a plurality of detection element rows are arranged in a slice direction (row direction, row direction). In the X-ray CT apparatus 1, the X-ray tube 11 and the X-ray detector 12 are integrally arranged around the subject P in a Rotate / Rotate-Type (third generation CT) and in a ring shape. There is a Stationary / Rotate-Type (4th generation CT) in which a large number of X-ray detection elements are fixed and only the X-ray tube 11 rotates around the subject P, and any type can be applied to the present embodiment. be. Hereinafter, in order to make the description concrete, the X-ray CT apparatus 1 of the present embodiment will be described by taking the third generation CT as an example.

Further, the X-ray detector 12 is an indirect conversion type detector having, for example, a grid, a scintillator array, and an optical sensor array. The scintillator array has a plurality of scintillators, and the scintillator has a scintillator crystal that outputs a photon amount of light according to an incident X dose. The grid is arranged on the surface of the scintillator array on the X-ray incident side, and has an X-ray shielding plate having a function of absorbing scattered X-rays. The grid may also be called a collimator (one-dimensional collimator or two-dimensional collimator). The optical sensor array has a function of converting into an electric signal according to the amount of light from the scintillator, and has, for example, an optical sensor such as a photomultiplier tube (PMT). The X-ray detector 12 may be a direct conversion type detector having a semiconductor element that converts incident X-rays into an electric signal. Further, the X-ray detector 12 may be a photon counting type X-ray detector. The X-ray detector 12 is an example of an X-ray detector.

The rotating frame 13 has an opening, and an X-ray tube 11 that generates X-rays is attached to the rotating frame 13. Specifically, the rotating frame 13 is an annular frame in which the X-ray tube 11 and the X-ray detector 12 are opposed to each other and the X-ray tube 11 and the X-ray detector 12 are rotated by a control device 18 described later. Is. The rotating frame 13 is rotatably supported by the fixed frame 5 via a support bearing. The rotating frame 13 receives power from the drive mechanism of the control device 18 and rotates around the rotating shaft R1 at a constant angular velocity.

The rotating frame 13 further includes an X-ray high voltage device 17 and a DAS 21 in addition to the X-ray tube 11 and the X-ray detector 12. Such a rotating frame 13 is housed in a substantially cylindrical housing having an opening forming a photographing space. The central axis of the opening coincides with the rotation axis R1 of the rotation frame 13. The detection data generated by the DAS 21 is transmitted from a transmitter having a light emitting diode (LED) to a receiver having a photodiode provided in a non-rotating portion (for example, a fixed frame 5) of the gantry device 10 by optical communication, for example. And transferred to the console device 40. The method of transmitting the detection data from the rotating frame 13 to the non-rotating portion of the gantry device 10 is not limited to the above-mentioned optical communication, and any method may be adopted as long as it is a non-contact type data transmission. The rotating frame 13 is provided with a first ring in the bearing 14.

FIG. 4 is a front view of the rotating frame 13 with respect to the rotating inner cooling pipe 15 and the first ring 141 connected to the X-ray tube 11. In FIG. 4, in order to clarify the connection relationship between the X-ray tube 11, the rotating inner cooling tube 15, and the first ring 141, the other components mounted on the rotating frame 13 are not shown.

FIG. 5 is a view of the gantry device 10 as viewed from the back side. In FIG. 5, the members on the back side of the brush 131 and the slip ring 132 along the Z axis are not shown. The brush 131 and the slip ring 132 are members for supplying electric power from the fixed frame 5 side to the components on the rotating frame 13 side. As shown in FIG. 5, a brush 131 and a second ring 142 of the bearing 14 are attached to the back surface side of the fixed frame 5. A slip ring 132 is attached to the back surface side of the rotating frame 13.

The brush 131 is provided on the fixed frame 5 so as to be in sliding contact with the slip ring 132. As a result, the brush 131 supplies power to the slip ring 132. The slip ring 132 is made of a metal such as copper or silver and is formed concentrically around the rotation axis R1. The slip ring 132 receives power from the brush 131.

As shown in FIGS. 4 and 5, the bearing 14 has a first ring 141 and a second ring 142, and assists the rotation of the rotating frame 13. The bearing 14 is one of a ball bearing, a roller bearing, and a sliding bearing. The bearing 14 is not limited to ball bearings, roller bearings, sliding bearings, and the like, and bearings having other structures such as magnetic bearings and fluid bearings may be used. The first ring 141 is provided on the rotating frame 13 along the circumferential direction of the rotating frame 13. The second ring 142 faces the first ring 141 and is provided on the fixed frame 5. The first ring 141 and the second ring 142 are arranged in parallel along the direction in which the top plate 33 is inserted into the opening, that is, the Z direction.

In the bearing 14, the heat generated in the X-ray tube 11 is conducted from the first ring 141 to the second ring 142 by the temperature gradient between the first ring 141 and the second ring 142. When the bearing 14 is composed of a ball bearing or a roller bearing, a plurality of rolling elements and a cage for holding the plurality of rolling elements are provided between the first ring 141 and the second ring 142. When the bearing 14 is a ball bearing, the rolling element corresponds to a ball, and when the bearing 14 is a roller bearing, the rolling element corresponds to a roller. Further, when the bearing 14 is realized by a plain bearing, the rolling element becomes unnecessary. The bearing 14 is a bearing for heat conduction that is different from the support bearing so that the rotating frame 13 can rotate around the rotating shaft R1 (Z-axis). The bearing 14 may be used as a support bearing.

The in-rotation cooling pipe 15 is connected to the X-ray tube 11. That is, the in-rotation cooling pipe 15 connects the X-ray tube 11 and the first ring 141. The in-rotation cooling pipe 15 is provided inside the first ring 141 with respect to the first ring 141. The in-rotation cooling pipe 15 may be provided adjacent to the first ring 141 with respect to the first ring 141. Hereinafter, for the sake of specificity, the in-rotation cooling pipe 15 will be described as being arranged inside the first ring 141 in the first ring 141. As shown in FIG. 3, the in-rotation cooling pipe 15 is arranged along the rotation frame 13. That is, the in-rotation cooling pipe 15 is provided on the rotating frame 13 along the circumferential direction of the first ring 141, and the first heat medium is injected. In other words, the in-rotation cooling pipe 15 is provided so as to orbit along the circumferential direction of the first ring 141. The in-rotation cooling pipe 15 may be provided so as to be folded back at at least one point along the circumferential direction of the first ring 141. That is, the in-rotation cooling pipe 15 may be folded back and arranged at at least two points on the outer circumference of the first ring 141 without orbiting the first ring 141 in the first ring 141. The first heat medium is, for example, a coolant. The first heat medium is not limited to a liquid, and may be various media such as a gas.

In the in-rotation cooling pipe 15, the coolant that conducts the heat generated in the X-ray tube 11 to the first ring 141 by a pump (hereinafter referred to as an in-rotation pump) (not shown) is the X-ray tube 11 and the first ring. It circulates with 141. The coolant corresponds to various cooling media such as water and cooling oil. The heat generated in the X-ray tube 11 is conducted to the first ring 141 through the in-rotation cooling tube 15 and the coolant. The in-rotation cooling pipe 15 may pass through a heat generating component (for example, DAS 21) mounted on the rotating frame 13 while the cooling liquid radiated by the first ring 141 heads for the X-ray tube 11.

When the X-ray tube 11 and the first ring 141 come into contact with each other and are mounted on the rotating frame 13, the in-rotating cooling tube 15 and the in-rotating pump become unnecessary. At this time, the heat generated in the X-ray tube 11 is conducted from the X-ray tube 11 to the first ring 141 according to the temperature gradient between the X-ray tube 11 and the first ring 141.

As for the non-rotating cooling pipe 16, the non-rotating cooling pipe 16 is provided on the fixed frame 5 along the circumferential direction of the second ring 142, and the second heat medium is injected. The second heat medium is, for example, a coolant. The second heat medium is not limited to a liquid, and may be various media such as a gas. Further, the first heat medium and the second heat medium may be different media. The non-rotating cooling pipe 16 is connected to a radiator 50 for cooling the second heat medium. Specifically, the non-rotating cooling pipe 16 connects the second ring 142 and the radiator 50. The non-rotating cooling pipe 16 is provided inside the second ring 142 with respect to the second ring 142. The non-rotating cooling pipe 16 may be provided adjacent to the second ring 142 with respect to the second ring 142. Hereinafter, for the sake of specificity, the external cooling pipe 16 will be described as being arranged inside the second ring 142 in the second ring 142. As shown in FIG. 5, the non-rotating cooling pipe 16 is arranged along the opening of the second ring 142. As shown in FIG. 5, the rotating outer cooling pipe 16 is arranged on the floor surface of the inspection room SR, for example, via the fixed frame 5, the erection frame 6, the base stand 7, and the gantry arm 8. NS. Subsequently, the non-rotating cooling pipe 16 is extended to the power supply room PR and connected to the radiator 50. The non-rotating cooling pipe 16 uses a pump provided in the radiator 50 (hereinafter, referred to as a non-rotating pump) to transfer a cooling liquid that absorbs heat conducted to the second ring 142 between the second ring 142 and the radiator 50. Circulate with. That is, the coolant is circulated between the second ring 142 and the radiator 50 by the non-rotating pump in the non-rotating cooling pipe 16. The heat in the second ring 142 is transferred to the radiator 50 via the non-rotating cooling pipe 16 and the coolant.

The X-ray high voltage device 17 has an electric circuit such as a transformer and a rectifier, and has a function of generating a high voltage applied to the X-ray tube 11 and a filament current supplied to the X-ray tube 11. It has a generator and an X-ray control device that controls an output voltage according to the X-rays emitted by the X-ray tube 11. The high voltage generator may be of a transformer type or an inverter type. The X-ray high voltage device 17 may be provided on the rotating frame 13 or on the fixed frame 5 side of the gantry device 10.

The control device 18 has a processing circuit having a CPU (Central Processing Unit) and the like, and a drive mechanism such as a motor and an actuator. The processing circuit has a processor such as a CPU and an MPU (Micro Processing Unit) and a memory such as a ROM (Read Only Memory) and a RAM (Random Access Memory) as hardware resources. Further, the control device 18 includes an integrated circuit for a specific application (Application Specific Integrated Circuit: ASIC), a field programmable gate array (Field Programmable Gate Array: FPGA), and another composite programmable logic device (Complex Programmable). ), It may be realized by a simple programmable logic device (SPLD). The control device 18 controls the X-ray high voltage device 17, the DAS 21, and the like in accordance with a command from the console device 40. The processor realizes the above control by reading and implementing the program stored in the memory.

Further, the control device 18 has a function of receiving an input signal from an input interface attached to the console device 40 or the gantry device 10 and controlling the operation of the gantry device 10 and the sleeper device 30. For example, the control device 18 controls to rotate the rotating frame 13 in response to an input signal, controls to tilt the gantry device 10, and controls to operate the bed device 30 and the top plate 33. The control for tilting the gantry device 10 is such that the control device 18 rotates the rotation frame 13 around the horizontal axis R2 based on the tilt angle (tilt angle) information input by the input interface attached to the gantry device 10. May be realized by. Further, the control device 18 may be provided in the gantry device 10 or in the console device 40. The control device 18 may be configured to directly incorporate the program into the circuit of the processor instead of storing the program in the memory. In this case, the processor realizes the above control by reading and executing a program incorporated in the circuit.

The wedge 19 is a filter for adjusting the X-ray dose of X-rays emitted from the X-ray tube 11. Specifically, the wedge 19 transmits and attenuates the X-rays emitted from the X-ray tube 11 so that the X-rays emitted from the X-ray tube 11 to the subject P have a predetermined distribution. It is a filter to do. The wedge 19 is, for example, a wedge filter or a bow-tie filter, which is a filter obtained by processing aluminum so as to have a predetermined target angle and a predetermined thickness.

The collimator 20 is a lead plate or the like for narrowing down the X-rays transmitted through the wedge 19 to the X-ray irradiation range, and a slit is formed by combining a plurality of lead plates or the like.

The DAS 21 has an amplifier that amplifies the electric signal output from each X-ray detection element of the X-ray detector 12, and an A / D converter that converts the electric signal into a digital signal, and has detection data. To generate. The detection data generated by DAS 21 is transferred to the console device 40. DAS21 is an example of a data collection unit. The in-rotation cooling pipe 15 may be arranged in the DAS 21.

The bed device 30 is a device for placing and moving the subject P to be scanned, and includes a base 31, a bed drive device 32, a top plate 33, and a top plate support frame 34. The base 31 is a housing that supports the top plate support frame 34 so as to be movable in the vertical direction. The bed drive device 32 is a motor or an actuator that moves the top plate 33 on which the subject P is placed in the long axis direction of the top plate 33. The sleeper drive device 32 moves the top plate 33 under the control of the console device 40 or the control device 18. The top plate 33 provided on the upper surface of the top plate support frame 34 is a plate on which the subject P is placed. In addition to the top plate 33, the bed drive device 32 may move the top plate support frame 34 in the long axis direction of the top plate 33.

The console device 40 includes a memory 41, a display 42, an input interface 43, and a processing circuit 44. Data communication between the memory 41, the display 42, the input interface 43, and the processing circuit 44 is performed via the bus (BUS).

The memory 41 is a storage device such as an HDD (Hard disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. The memory 41 stores, for example, projection data and reconstructed image data. In addition to the HDD and SSD, the memory 41 is connected to a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versaille Disc), or a flash memory, or a semiconductor memory element such as a RAM (Random Access Memory). It may be a drive device that reads and writes various information. Further, the storage area of the memory 41 may be in the X-ray CT device 1 or in an external storage device connected by a network. Further, the memory 41 stores the control program according to the present embodiment. The memory 41 stores the volume data generated by the prescan.

The display 42 displays various information. For example, the display 42 outputs a medical image (CT image) generated by the processing circuit 44, a GUI (Graphical User Interface) for receiving various operations from the operator, and the like. For example, as the display 42, for example, a liquid crystal display (LCD: Liquid Crystal Display), a CRT (Casode Ray Tube) display, an organic EL display (OELD: Organic Electro Luminescence Display), a plasma display or any other display may be appropriately used. , Can be used. Further, the display 42 may be provided on the gantry device 10. Further, the display 42 may be a desktop type, or may be composed of a tablet terminal or the like capable of wireless communication with the console device 40 main body.

The input interface 43 receives various input operations from the operator, converts the received input operations into electric signals, and outputs the received input operations to the processing circuit 44. For example, the input interface 43 receives from the operator collection conditions for collecting projection data, reconstruction conditions for reconstructing a CT image, image processing conditions for generating a post-processed image from a CT image, and the like. .. As the input interface 43, for example, a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touch pad, a touch panel display, and the like can be appropriately used.

In the present embodiment, the input interface 43 is not limited to the one provided with physical operation parts such as a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touch pad, and a touch panel display. For example, an example of the input interface 43 includes an electric signal processing circuit that receives an electric signal corresponding to an input operation from an external input device provided separately from the device and outputs the electric signal to the processing circuit 44. .. The input interface 43 is an example of an input unit. Further, the input interface 43 may be provided in the gantry device 10. Further, the input interface 43 may be composed of a tablet terminal or the like capable of wireless communication with the console device 40 main body.

The processing circuit 44 controls the operation of the entire X-ray CT apparatus 1 in response to the electrical signal of the input operation output from the input interface 43. For example, the processing circuit 44 has a processor such as a CPU, an MPU, and a GPU (Graphics Processing Unit) and a memory such as a ROM and a RAM as hardware resources. The processing circuit 44 executes the system control function 441, the preprocessing function 442, and the reconstruction processing function 443 by the processor that executes the program expanded in the memory. The processing circuit 44 that executes the system control function 441, the preprocessing function 442, and the reconstruction processing function 443, respectively, corresponds to the system control unit, the preprocessing unit, and the reconstruction unit. It should be noted that each function 441 to 443 is not limited to the case where it is realized by a single processing circuit. A processing circuit may be formed by combining a plurality of independent processors, and each function 441 to 443 may be realized by executing a program by each processor.

The processing circuit 44 controls each function of the processing circuit 44 based on the input operation received from the operator via the input interface 43 by the system control function 441. Specifically, the system control function 441 reads out the control program stored in the memory 41, expands it on the memory in the processing circuit 44, and controls each part of the X-ray CT apparatus 1 according to the expanded control program. .. For example, the processing circuit 44 controls each function of the processing circuit 44 based on an input operation received from the operator via the input interface 43.

The processing circuit 44 generates data obtained by performing preprocessing such as logarithmic conversion processing, offset correction processing, interchannel sensitivity correction processing, and beam hardening correction on the detection data output from DAS21 by the preprocessing function 442. do. The data before preprocessing is referred to as raw data, and the data after preprocessing is referred to as projection data.

The processing circuit 44 uses a filter correction back projection method (FBP method: Filtered Back Projection), a successive approximation reconstruction method, or the like with respect to the projection data generated by the preprocessing function 442 by the reconstruction processing function 443. Reconstruction processing is performed to generate CT image data. The reconstruction processing function 443 stores the reconstructed CT image data in the memory 41.

The radiator 50 is connected to the non-rotating cooling pipe 16. The radiator 50 releases heat from the coolant that has absorbed the heat in the second ring 142. The radiator 50 is installed in a room different from the inspection room SR in which the gantry device 10 having the fixed frame 5 and the rotating frame 13 is installed, for example, the power supply room PR. The room in which the radiator 50 is installed is not limited to the power supply room PR, and may be installed in any room such as a machine room as long as it is a room different from the inspection room SR. Since the structure of the radiator 50 is the same as that of a general radiator, detailed description thereof will be omitted.

FIG. 6 is a diagram showing an example of the positional relationship between the bearing 14, the rotating inner cooling pipe 15, the rotating outer cooling pipe 16, the X-ray tube 11, and the radiator 50 when the gantry device 10 is viewed from the side surface. As shown in FIG. 6, the first ring 141 and the second ring 142 are arranged in parallel along the direction in which the rotation axis R1 extends. That is, the first ring 141 and the second ring 142 are arranged in parallel along the Z direction. FIG. 7 is an enlarged view of a part of EP1 in FIG. As shown in FIGS. 6 and 7, the heat generated in the X-ray tube 11 is endothermic to the coolant in the in-rotation cooling tube 15 in the X-ray tube 11. As the in-rotation cooling pipe 15 passes through the first ring 141, the heat in the coolant is conducted to the first ring 141. The heat in the first ring 141 is conducted through the rolling element 143, which is a ball or roller, or directly to the second ring 142. The heat in the second ring 142 is endothermic to the coolant in the non-rotating cooling pipe 16. The heat of the coolant in the non-rotating cooling pipe 16 is released into the power supply chamber PR via the fan in the radiator 50. Due to the heat transfer described above, the heat generated in the gantry device 10, for example, the heat generated by the X-ray tube 11 is released in a room such as a power supply room PR different from the inspection room SR.

According to the X-ray CT apparatus 1 according to the embodiment described above, the first ring 141 provided on the rotating frame 13 along the circumferential direction of the rotating frame 13 and the fixed frame 5 facing the first ring 141 A bearing 14 having a second ring 142 provided and assisting the rotation of the rotating frame 13, and a first heat medium provided on the rotating frame 13 along the circumferential direction of the first ring 141 to be injected. The heat generated in the X-ray tube 11 is transferred through the tube 15 of 1 and the second tube 16 provided in the fixed frame 5 along the circumferential direction of the second ring 142 and into which the second heat medium is injected. , Conducts from the rotating frame 13 side to the fixed frame 5 side. Next, the X-ray CT apparatus 1 is provided adjacent to the second ring 142 or inside the second ring 142 along the circumferential direction of the second ring 142, and the second heat medium is circulated for external cooling. The heat of the coolant is released (exhausted) from the pipe 16 and the radiator 50 connected to the non-rotating cooling pipe 16. Further, the radiator 50 is installed in a room different from the inspection room SR in which the gantry device 10 is installed. As a result, according to the X-ray CT apparatus 1 according to the embodiment, for example, the heat generated in the X-ray tube 11 can be released to a room different from the examination room SR.

From the above, according to the X-ray CT apparatus 1 according to the embodiment, the heat released in the gantry device 10 can be reduced, so that the number of fans installed on the exterior cover of the gantry device 10 can be reduced. And the rotation speed of the fan can be reduced. As a result, according to the X-ray CT apparatus 1, the noise caused by the fan can be reduced in the examination room SR. In addition, according to the X-ray CT apparatus 1, it is possible to reduce the diffusion of dust generated by the brush 131 into the laboratory SR. From these facts, according to this X-ray CT apparatus 1, it is possible to provide a clean and quiet environment in the examination room SR without disturbing the conversation of the engineer.

(Modification example)
In this modification, the second ring 142 may be provided on the outer peripheral side of the first ring 141. FIG. 8 is a front view of the rotating frame 13 with respect to the rotating inner cooling pipe 15 and the first ring 141 connected to the X-ray tube 11. In FIG. 8, in order to clarify the connection relationship between the X-ray tube 11, the rotating inner cooling tube 15, and the first ring 141, the other components mounted on the rotating frame 13 are not shown. As shown in FIG. 8, in the bearing 14 having the first ring 141 and the second ring 142, the first ring 141 corresponds to the inner ring and the second ring 142 corresponds to the outer ring.

FIG. 9 is an enlarged view of a part of EP2 in FIG. As shown in FIGS. 8 and 9, the heat generated in the X-ray tube 11 is transferred to the radiator 50 via the coolant in the in-rotation cooling tube 15 and the coolant in the bearing 14 and the out-rotation cooling tube 16. .. The heat transferred to the radiator 50 is released into the power supply room PR via the fan. The same effect as that of the embodiment can be realized by this modification. As a further modification of the present embodiment, the bearing 14 in the embodiment and the bearing 14 in the modification may be mounted on the rotating frame 13 and the fixed frame 5, respectively.

According to at least the embodiments and modifications described above, the noise caused by the fan can be reduced in the inspection room.

Although some embodiments have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other embodiments, and various omissions, replacements, changes, and combinations of embodiments can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

1 X-ray CT device 5 Fixed frame 6 Standing frame 7 Base stand 8 Stand arm 10 Mount device 11 X-ray tube 12 X-ray detector 13 Rotating frame 14 Bearing 15 In-rotating cooling tube (first tube)
16 Rotating outer cooling pipe (second pipe)
17 X-ray high voltage device 18 Control device 19 Wedge 20 Collimator 21 DAS (Data Acquisition System)
30 Sleeper device 31 Base 32 Sleeper drive device 33 Top plate 34 Top plate support frame 40 Console device 41 Memory 42 Display 43 Input interface 44 Processing circuit 50 Radiator 131 Brush 132 Slip ring 141 1st ring 142 2nd ring 143 Rolling element 441 System control function 442 Preprocessing function 443 Reconstruction processing function

Claims (11)

A fixed frame that rotatably supports a rotating frame with an X-ray tube that generates X-rays around the axis of rotation,
It has a first ring provided on the rotating frame along the circumferential direction of the rotating frame and a second ring provided on the fixed frame facing the first ring and assists the rotation of the rotating frame. Bearings and
A first tube provided in the rotating frame along the circumferential direction of the first ring and into which the first heat medium is injected, and
A second tube provided in the fixed frame along the circumferential direction of the second ring and into which the second heat medium is injected, and
X-ray computed tomography equipment equipped with. The first tube is provided adjacent to or inside the first ring.
The second tube is provided adjacent to or inside the second ring.
The X-ray computed tomography apparatus according to claim 1. The X-ray computed tomography apparatus according to claim 1 or 2, wherein the second tube is connected to a radiator for cooling the second heat medium. The radiator is installed in a room different from the inspection room in which the gantry device having the rotating frame and the fixed frame is installed.
The X-ray computed tomography apparatus according to claim 3. The first ring and the second ring are arranged in parallel along the direction in which the rotation axis extends.
The X-ray computed tomography apparatus according to any one of claims 1 to 4. The second ring is arranged on the outer peripheral side of the first ring.
The X-ray computed tomography apparatus according to any one of claims 1 to 4. The first tube is connected to the X-ray tube.
The X-ray computed tomography apparatus according to any one of claims 1 to 6. The X-ray computed tomography apparatus according to any one of claims 1 to 7, wherein the first tube is provided so as to orbit along the circumferential direction of the first ring. The X-ray computed tomography apparatus according to any one of claims 1 to 7, wherein the first tube is provided so as to be folded back at at least one point along the circumferential direction of the first ring. The X-ray tube and the first ring come into contact with each other.
The X-ray computed tomography apparatus according to any one of claims 1 to 9. The bearing is one of a ball bearing, a roller bearing, and a sliding bearing.
The X-ray computed tomography apparatus according to any one of claims 1 to 10.

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