WO2021006166A1

WO2021006166A1 - Computer tomography device and examination vehicle

Info

Publication number: WO2021006166A1
Application number: PCT/JP2020/025950
Authority: WO
Inventors: 雫石　誠
Original assignee: 雫石　誠
Priority date: 2019-07-09
Filing date: 2020-07-02
Publication date: 2021-01-14
Also published as: JPWO2021006166A1; JP6858317B1

Abstract

[Problem] To facilitate movement or installation of a CT device and reduce maintenance load such as repair and replacement of used parts by reducing the size, weight, and power consumption of an X-ray CT and solving the stroke region of the X-ray CT. Furthermore, to facilitate mounting of the X-ray CT device, and achieve an examination vehicle capable of preventing in-hospital infection. [Solution] This CT device has a gantry that has a rotational part rotating around a body axis direction as a center axis and is movable in the vertical direction, wherein permanent magnets or electromagnets are installed between the rotational part and a fixed part so as to face each other. Furthermore, in this examination vehicle on which the CT device in mounted, the entrance of the CT device is provide to a side surface section of a vehicle body or to a rear side surface section of the vehicle body.

Description

Computer tomography equipment and examination vehicle

The present invention relates to a computer tomography apparatus capable of undergoing an examination while a subject is standing or sitting, and a mobile examination vehicle equipped with the computer tomography apparatus.

An X-ray computed tomography (CT) device is a gantry including a rotating part that rotates around an image object, a berth moving device that moves a berth on which a subject is placed so as to pass inside the gantry in the axial direction. It is composed of a slip ring that enables electrical connection with the rotating unit, an operation including an image drawing unit that processes image data transferred to the outside via the slip ring, and a monitor unit. Inside the rotating unit, there is a detector consisting of an aggregate of a large number of image sensors, a circuit board that processes signals from the detector, an X-ray generator located opposite to an imaging object such as a subject, and cooling. It has a built-in fan, high-voltage power supply circuit, etc. The CT device is a large, heavy, and expensive diagnostic imaging device. In addition to the installation cost of the building, power supply, air conditioner, etc. where the CT device body is installed, the maintenance cost to maintain the optimum performance of the device at all times. Is also a heavy burden. Therefore, there are various difficulties in moving the CT device to change the installation location or using it outdoors. Conventionally, vehicles equipped with an X-ray inspection device or the like are known, but in order to secure a stroke area, it is inevitable that the vehicle itself becomes large, and each subject enters the vehicle and undergoes an inspection. It took a long time, and it was difficult to efficiently perform imaging tests on a large number of subjects.

By reducing the size and price of CT equipment such as X-ray computer tomography equipment, we will contribute to maintaining the health of people all over the world. In particular, it is desirable to detect cancer and other diseases at an early stage and reduce the increasing medical costs. It is also necessary to eliminate medical disparities resulting from natural disasters and regional conflicts by providing the latest and highest standards of medical services, even in developing countries and other remote and depopulated areas. Various unsolved technical problems remain as factors for increasing the size or cost of CT equipment, and no effective breakthrough has yet been found. In addition, medical vehicles equipped with X-ray equipment (also called X-ray vehicles in Japan) have the primary purpose of screening a large number of subjects, and if any suspicious findings are found, they will be specialized again at a later date. It is necessary to go to a hospital or an inspection institution to undergo a detailed examination using a CT device or the like. However, for the elderly and those who live in depopulated areas, the fact is that it is extremely time-consuming, physical, or financially burdensome to undergo a detailed examination again. In order to use the CT device in a moving means such as a vehicle, it is essential to reduce the size and weight of the CT device itself, reduce the required space, and secure a stroke area for horizontal movement of the bed. Further, since each subject enters the vehicle and lays down on the bed, the examination time per person becomes long, and there is a problem that it is difficult to efficiently perform CT examinations on a large number of subjects. Further, in order to expand the room for mounting other medical devices and the like on the vehicle, the minimization of the space provided for the CT device and the subject, and the speeding up of the examination and diagnosis are also issues to be solved. Furthermore, in recent years, the worldwide spread of infectious diseases, the so-called pandemic threat, has become more serious. Having a subject who may be suffering from such an infection undergo a CT examination at a hospital or laboratory as before inevitably risks spreading the infection to other patients and medical staff. Therefore, for example, in order to detect early pneumonia caused by a new type of coronavirus infection or the like at an early stage, there is a problem that it is hindered from performing CT imaging on many patients in a place where there are patients.

In order to use the CT device in the means of transportation such as the vehicle, it is an issue to reduce the size and weight of the CT device. The rotating part in the gantry contains an X-ray source, a detector, a detector signal processing circuit, an X-ray source drive control circuit, an air cooling fan, and the like. However, the X-ray source, the X-ray source drive control circuit, the air-cooled fan, etc. are heavy, and the moment of inertia and heavy objects when these are rotated at a speed of 0.5 rotations or more per second on the circumference in the gantry. It is necessary to minimize the harmful effects such as vibration and noise caused by rotation. In addition, it is necessary to reduce the area occupied by the CT apparatus main body and the stroke area during use in the vehicle. One of the factors that hinders the miniaturization of CT devices is that it is difficult to reduce the size and weight of the gantry. This is to increase the area of the detector using the glass substrate, that is, to increase the slice width, the corresponding X-ray light source, the high voltage power supply, and the air cooling fan for cooling them. Due to the increase in size, weight, and data transmission amount per unit time, the rotation speed of the rotating portion is limited to about 0.5 to 2 rotations per second at most. It is difficult to supply a large current to the rotating part via a slip ring, and vibration and noise due to rotation, or the durability of mechanical parts such as ball bearings inserted between the rotating part and the fixed part in the gantry. This is because there are problems of deterioration and lubrication. Therefore, in order to reduce the size and weight of the CT device, the above-mentioned X-ray source, detector, detector signal processing circuit, X-ray source drive control circuit, air-cooling fan, etc. are reduced in size and weight, and are equivalent to or equal to the conventional one. It is necessary to realize the above shooting performance.

As described above, since the detector or the like rotates around the body axis direction inside the gantry, an electrical contact means called a slip ring for supplying power or reading the output signal of the detector or the like to the outside is adopted. There is. In order to ensure the electrical connection by the slip ring, it is necessary to keep the number of revolutions low and the number of signal lines to be low. In order to reduce the number of signal lines, a method of serializing a parallel signal and reading it out via a slip ring is adopted. However, since the transmission frequency rises when a large amount of imaging data is serially transmitted, it is necessary to develop a dedicated semiconductor device such as a high-speed line buffer element, and it is inevitable that power consumption and heat generation will increase as the transmission frequency rises. .. In recent years, in order to expand the exposure area by X-ray pulse irradiation in the body axis direction, the structure is shifting to a structure in which the slice width is widened. As a result, in addition to increasing the weight of the gantry itself, it is inevitable that the X-ray generator will become larger. Further, in order to expand the light receiving area (that is, the number of slices) in the body axis direction, the light receiving area of the detector used is increased, that is, the number of pixels is increased, and further high-speed and large-capacity data transmission and external recording are performed. High-speed real-time recording on media is required. However, an increase in transmission frequency is unavoidable for the transmission of a large amount of imaging data, and it is necessary to develop a dedicated semiconductor element such as a high-speed line buffer element. In addition, it is inevitable that power consumption and heat generation will increase as the transmission frequency rises. For example, when the number of slices is 64, a data processing speed exceeding 1 gigabyte / sec is required. In order to record a large amount of data in real time at high speed, it is necessary to use a combination of a plurality of hard disks such as RAID (Redundant Arrays of Independent Disks). It is also a problem to be solved to reduce or eliminate such an adverse effect due to an increase in the transmission frequency.

Similarly, there are still problems to be solved in the supply of electric power via the slip ring. As described above, in recent years, as the slice width has increased, the size of the X-ray source has increased, that is, the amount of current supplied to the X-ray source drive control circuit including the high-voltage generation circuit has tended to increase as the tube current increases. is there. As a result, the slip ring needs to pass a large current while sliding at high speed with respect to the brush, and the contact surface generates heat and causes seizure. Therefore, maintenance such as surface polishing of slip rings and brushes and regular replacement of members is essential. On the other hand, when the CT device is operated outdoors or in a remote place, a large capacity and stable supply of commercial power cannot be expected. It is also an issue to be solved to adapt to the usage environment that is premised on power supply by private power generation equipment or vehicle power supply. By reducing the size and weight of the CT device and reducing the power consumption described above, it is possible to significantly reduce the power consumption of the CT device itself. In addition, considering the outdoor use by vehicles and the like, repairs or reduction of regular maintenance load are also issues to be solved.

The present invention comprises a gantry having a rotating portion that rotates about the body axis direction, and a control unit that processes and displays image data sent from the gantry. At least, it is a CT device with a built-in light source and light source drive control circuit in the rotating part, and the central axis is in the vertical direction, and the rotating part and the fixed part surrounding the rotating part are combined in the vertical direction to form the rotating part. A CT device in which magnets or electromagnetic induction means for generating a magnetic field are arranged close to each other at positions where the fixed portions face each other.

Preferably, the CT apparatus is a CT device in which the rotating portion is located above the fixed portion at the facing position and magnets are attached to the rotating portion and the fixed portion so that the same polarities face each other at the facing positions. Alternatively, the CT device is a CT device in which the rotating portion is located below the fixed portion at the facing position and magnets are attached to the rotating portion and the fixed portion so that different polarities face each other at the facing position.

Preferably, it is a CT device in which the rotating portion is located above the fixed portion at the facing position, the rotating portion has a magnet at the facing position, and the electromagnetic induction means is arranged at the fixed portion. Alternatively, it is a CT device in which the rotating portion is located below the fixed portion at the facing position, the rotating portion has a magnet at the facing position, and the electromagnetic induction means is arranged at the fixed portion.

Preferably, it is a CT device having a drive motor for rotating the rotating portion and a timing belt for transmitting the rotational torque of the drive motor to the rotating portion. Alternatively, the CT device has a gear structure having different numbers of teeth to transmit the rotational torque of the drive motor that rotates the rotating portion to the rotating portion on the rotation shaft of the drive motor and the circumference of the rotating portion. Alternatively, a direct drive motor structure is used in which the rotating portion is a rotor and the fixing portion is a stator.

Preferably, the rotating portion is a CT device having at least a light source, a light source drive control circuit, and a secondary battery for driving them. Further, the CT device has a detector, a detector drive control circuit, and a digital signal processing circuit for processing the output signal of the detector built in the rotating unit. Further, the CT apparatus has a built-in semiconductor image memory for recording the data obtained from the detector.

A CT device having a detector on the inner circumference of the fixed portion facing the outer peripheral portion of the rotating portion is preferable. Further, the CT apparatus has an opening in the rotating portion, which is a portion facing the rotating portion of the light source across the rotation center and exposes the light receiving surface of the detector by passing the emitted light from the light source.

Preferably, the CT apparatus in which the detector is formed on a silicon semiconductor substrate and the longitudinal direction of the peripheral circuit block formed on the same semiconductor substrate is parallel to the normal direction of the circumference having the central axis as the rotation axis. And. Further, the CT device has a light receiving surface of the detector curved about the central axis.

Preferably, a lithium ion battery is used as the secondary battery. Further, a large-capacity semiconductor memory, for example, a non-volatile memory such as a NAND flash memory is used as the image memory. The light source is an X-ray light source or a near infrared (NIR) light source. Preferably, the light source is an X-ray light source, and the electron beam generating portion of the X-ray light source is formed of carbon nanostructures. The detector is preferably a silicon semiconductor detector, and has a structure in which an AD conversion circuit is formed in the silicon semiconductor detector. Preferably, the detector is either a photomultiplier tube type detector, an avalanche diode (APD) type detector, or a photon counting type detector. Preferably, a radiation shielding optical fiber plate is formed on the upper part of the detector, or a radiation scintillator is further laminated on the radiation shielding optical fiber plate.

A CT device in which the gantry moves in the central axis direction. Alternatively, the CT device is such that the stage on which the subject stands or the chair on which the subject sits moves in the central axis direction with respect to the stationary gantry.

Any of the above light source, secondary battery, detector, or semiconductor image memory has a cartridge structure, and the light source, secondary battery, detector, or semiconductor image memory having a cartridge structure is individually inserted or inserted into the rotating portion. A CT device having a cartridge opening for removal.

Preferably, the host is electrically connected by facing the rotating unit interface and mechanically contacting the rotating unit in a stopped state, or by electromagnetically coupling in a non-contact state by the interaction of an electromagnetic field. A CT device having an interface in a fixed portion around a rotating portion. Further, the rotating unit interface and the host interface are CT devices that face each other in the central axis direction or in a radial direction close to the central axis. Alternatively, the CT device has a structure in which the rotating portion interface is formed as a ring-shaped electrode over the entire circumference of the annulus on the side surface side of the rotating portion and is connected to the host interface composed of convex connection terminals. Alternatively, the CT device has a wireless communication interface in the rotating unit that transmits data inside the semiconductor image memory to the outside of the rotating unit. Alternatively, the CT device has a wireless interface for transmitting and receiving a control signal for controlling the imaging operation of the gantry by wireless communication in a fixed portion or a rotating portion inside the control unit and the gantry.

Preferably, the host is electrically connected by facing the rotating unit interface and mechanically contacting the rotating unit in a stopped state, or by electromagnetically coupling in a non-contact state by the interaction of an electromagnetic field. A CT device having an interface in a fixed portion around a rotating portion. Alternatively, the rotating unit interface and the host interface are CT devices that face each other in the central axis direction or in a radial direction close to the central axis. Alternatively, the CT device has a structure in which the rotating portion interface is formed as a ring-shaped electrode over the entire circumference of the annulus on the side surface side of the rotating portion and is connected to the host interface composed of convex connection terminals. Alternatively, the CT device has a wireless communication interface in the rotating unit that transmits data inside the semiconductor image memory to the outside of the rotating unit. Alternatively, the CT device has a control unit and a CT device inside the gantry that transmits and receives control signals for controlling the imaging operation of the gantry by wireless communication.

When the rotating part is stopped, it rotates the host interface that is electrically connected by facing the rotating part interface and mechanically contacting it, or by electromagnetically coupling it in a non-contact state due to the interaction of an electromagnetic field. It is a CT device provided in a fixed portion around the portion. Alternatively, the rotating unit interface and the host interface are CT devices that face each other in the central axis direction or in a radial direction close to the central axis. Alternatively, the CT device has a structure in which the rotating portion interface is formed as a ring-shaped electrode over the entire circumference of the annulus on the side surface side of the rotating portion and is connected to the host interface composed of convex connection terminals. Alternatively, the CT device has a wireless interface for transmitting and receiving control signals for controlling the imaging operation of the gantry by wireless communication in the control unit and the rotating unit.

The structure is such that the rotating unit interface and the host interface face each other at a predetermined position within the movement range of the gantry. Preferably, the predetermined position is at the end point of the movement range of the gantry. Further, the rotating unit interface and the host interface are close to each other in the vertical direction and face each other. Alternatively, the rotating unit interface and the host interface are close to each other in the central axis direction and face each other. Alternatively, the rotating unit interface and the host interface are electrically connected by mechanically contacting each other at a predetermined position. Alternatively, it is a non-contact interface in which the rotating unit interface and the host interface are close to each other at a predetermined position and electrically connected by the interaction of an electromagnetic field in a non-contact state. Further, a driving means for moving the gantry in the central axis direction is provided inside the gantry. Further, a drive motor for rotating the rotating portion is provided inside the gantry.

Preferably, the cradle is provided at the top or bottom of the column, and the cradle is provided with a host interface. Further, the cradle is provided with an inspection probe for inspecting and calibrating the rotating part or a holding means for holding a standard sample. Alternatively, the cradle has a hold mechanism for holding and fixing the rotating portion at a predetermined position, or a cooling mechanism for cooling.

A medical examination or inspection vehicle equipped with the above CT device. Preferably, the entrance to the CT device is a medical examination or inspection vehicle located on the side surface portion or the rear side surface portion of the vehicle. Further, it is assumed that the air pressure in one section occupied by the CT device inside the inspection vehicle is lower than the air pressure in the other sections inside the inspection vehicle and the moving passage. Alternatively, the medical examination or inspection vehicle having a ventilation means for exhausting the air in the section where the CT device is installed to the outside of the vehicle.

Preferably, it is the medical examination or inspection vehicle in which the power source for driving the CT device is a fuel cell using hydrogen gas.

Since the CT device has been made smaller and lighter, and the power consumption has been reduced, and the stroke area has been eliminated by the vertical movement of the gantry section, the space for installing the CT device, the building and power supply, the construction of air conditioning equipment, etc. Maintenance costs can be significantly reduced. Furthermore, since the number of slip rings and brushes for making electrical connections with them can be reduced or eliminated, the frequency of sparks and failures associated with power supply with a large amount of current can be significantly reduced and reliability is reduced. Can be improved. In addition, permanent magnets or electromagnets are placed on the rotating part and the fixed part, and the magnetic force that repels or attracts each other can be used to reduce the load that the weight of the rotating part applies to mechanical parts such as ball bearings. It is possible to obtain the effect of reducing the starting torque when rotating the ball bearing, or reducing the wear of ball bearings and the generation of noise due to high-speed rotation. Further, the rotating portion can be easily rotated at a high speed of, for example, 2 to 10 rotations per second. Furthermore, since a CMOS type detector with an integrated signal processing circuit using on-chip or laminated elements and an X-ray source using carbon nanostructures can be used, a CT equipped with a gantry unit with low noise and low power consumption can be used. The device can be realized. Alternatively, a small photomultiplier tube or other high-sensitivity detector can be used, so that the radiation exposure dose of the subject can be reduced. In addition, since the components inside the gantry, such as the X-ray source, X-ray detector, and secondary battery, have a cartridge structure, the gantry itself does not need to be disassembled and repaired, and only the defective part is extracted and new. By inserting components, the time and cost required for repairs can be significantly reduced. In addition, inventory of maintenance parts to maintain optimum equipment performance at all times, or annual maintenance costs and equipment downtime can be significantly reduced. Further, the inspection vehicle for medical examination equipped with the CT device according to the present invention enables quick and accurate initial diagnosis in a remote place, a disaster-occurring area, or the like. In particular, even in developing countries, other remote areas and depopulated areas, by providing the latest and high-level medical services, medical disparities resulting from natural disasters and regional conflicts can be eliminated. Furthermore, since it is possible to move away from hospitals and testing facilities and flexibly move to the suburbs or remote areas near patients with infectious diseases, etc., to perform testing and diagnosis, it is easy to end early pandemics and prevent nosocomial infections.

(A) is a perspective view of the CT device 100 according to the embodiment, and (b) is a side view perspective view of the inspection vehicle 500 according to the embodiment. (A) is an XY plan view seen from the Z-axis direction for explaining the structure of the fixed portion 24 and the rotating portion 23 inside the gantry 5. (B) is an XY plan view seen from the direction opposite to the central axis 1 in order to explain the structure of the fixed portion 24 and the rotating portion 23 inside the gantry 5. (C) is a perspective view for explaining another rotation drive structure of the rotation part 23. (A) is a cross-sectional structure view of the gantry 5 as viewed from the X-axis or Y-axis direction. (B) to (e) are cross-sectional views for explaining a modified example of the structure of the portion A surrounded by the broken line in (a). (A) is a plan view seen from the Z-axis direction for explaining the internal structure of the rotating portion 23 inside the gantry 5. (B) is a circuit configuration diagram for explaining the inside of the rotating portion 23, particularly the detector and its peripheral circuits. (C) It is a circuit block diagram for demonstrating the inside of the rotating part 23, particularly the X generation part and a high voltage drive circuit. (A) is a plan view of the gantry portion of the CT device 200 according to the modified example of the CT device 100 as viewed from the Z-axis direction. (B) and (c) are cross-sectional structural views viewed from the X-axis or Y-axis direction for explaining the structure of the gantry portion of the CT device according to the modified example of the CT device 200. (A) is a XY plan view of the CT device 300 according to a modification of the CT device 200, particularly the gantry portion viewed from the Z-axis direction, and (b) is a cross-sectional structure view also seen from the X-axis or Y-axis direction. Yes, (c) is an enlarged view of a portion B surrounded by a broken line in (a). (D) is a plan view when the direction of the opening 28 is viewed from the X-ray source 25 m in order to explain the opening 28 formed in the rotating portion 23, and the opening 28 is arranged in the fixed portion 24. A part of the plurality of detector units 30 is visible. (A) is a plan view of a CMOS type solid-state image sensor 30-1, which is a detector unit suitable for the detector unit 30 used in the CT apparatus 300. (B) is another detector unit suitable for the detector unit 30 used in the CT apparatus 300, and the CMOS type solid-state image sensor 30-2 is arranged so as to face each other so that the light receiving regions are in close contact with each other. It is a plan view of. (C) is an enlarged cross-sectional view for explaining the cross-sectional structure of the CMOS type solid-state image sensor 30-2 in (b). (A) is a side view of the image pickup apparatus 400 according to the embodiment as viewed from the X-axis direction, and (b) is a block diagram for explaining the circuit configuration of the wireless power feeding portion in the non-contact interface portions (10 and 12). is there. In (c) and (d), the state before the secondary battery (27 m) having a removable cartridge structure was connected to the cartridge holder 22 in the cradle was attached to the cartridge holder 22 from the X-axis direction. It is a conceptual diagram which looked at the state before taking in the charged secondary battery (27 m) into a gantry from the Y-axis direction. (A) and (b) are side views of the inspection vehicle 600 and the inspection vehicle 700 according to the modified example of the inspection vehicle 500, respectively. (C) and (d) are plan views seen from the Z-axis direction of the inspection vehicle 600 and the inspection vehicle 700 according to the modified example of the inspection vehicle 500, respectively. (A) and (b) are side views of the inspection vehicle 800 and the inspection vehicle 900 according to the modified example of the inspection vehicle 500, respectively. (C) is a flowchart for explaining the driving method of the inspection vehicle 800.

In the present invention, the moving direction of the gantry or the sleeper, that is, the "body axis direction" is defined as the Z axis, and the plane perpendicular to the Z axis is defined as the XY plane. FIG. 1A is a perspective view of the CT device 100 according to the embodiment. In the CT device 100, the Z-axis direction coincides with the horizontal plane, that is, the direction of gravity. Therefore, the moving direction of the gantry 5 is also the vertical direction, that is, the Z-axis direction. The CT device 100 has a vertical sleeper that determines the standing position of the subject, or a portion 3 called a back plate. Inside the gantry 5, there is a rotatable rotating portion 23, and the rotation center axis 1 is parallel to the Z axis, that is, the body axis direction. A motor or the like for pulling up or lowering the gantry 5 is built in either the ceiling portion (9-1) of the CT device or the bottom portion (9-2) on which the subject rides. The ceiling portion and the bottom portion are the end points of the gantry 5, and may be referred to as a cradle as described later. Two columns 7-1 and 7-2 for holding the cradle and the gantry 5 are provided. It should be noted that there is an operation / control unit and a display (monitor) unit (not shown), and a tomographic image or the like reconstructed by an image drawing circuit, image processing software, or the like is displayed on the monitor. As will be described in detail below, the miniaturization and weight reduction of the gantry portion according to the present invention facilitates the vertical movement of the gantry, and the subject undergoes a CT examination while standing or sitting on a chair. Will be possible. Further, it becomes easy to mount the CT device on the vehicle and actually use the CT device installed in the vehicle at the moving destination. This is because with the conventional CT device, it is necessary to secure the sleeper itself and the space for moving the sleeper in the horizontal direction, that is, the stroke area in the vehicle, and it is difficult to miniaturize the inspection vehicle equipped with the CT device. ..

FIG. 1B is a side view of the inspection vehicle 500 according to the embodiment. In this embodiment, the height direction of the vehicle, that is, the vertical direction is the Z axis, and the above-mentioned CT device 100 shown by a broken line is mounted. As described above, since the subject can undergo the CT examination while standing or sitting on a chair, the examination vehicle can be miniaturized and the examination time per person can be shortened. At the rear of the vehicle, there is an entrance and a passage (neither shown) for entering the inside of the inspection vehicle 500, and the inside of the vehicle can be entered using the stairs or the step stool 17. Further, as will be described later, in order to utilize natural energy, for example, a solar panel 13 is provided.

The structure of the gantry 5 suitable for the CT apparatus 100 according to the embodiment will be described with reference to FIG. FIG. 2A is a plan view of the gantry 5 as viewed from the Z-axis direction. A fixing portion 24 is combined around the rotating portion 23 via a ball bearing or the like (not shown). The rotating unit 23 is rotated around the central shaft 1 by a rotating unit rotating belt (or called a timing belt) 21 and a rotating unit drive motor 19. FIG. 2B is a plan view of the gantry 5 as viewed from the Z-axis direction, but FIG. 2A is a plan view of the gantry 5 as viewed from the opposite side of the central axis 1. The rotating unit 23 includes a light source, for example, an X-ray generating unit 25, a light source driving circuit 29, a detector array 31, a detector peripheral circuit 33, a detector drive control circuit 41, and a ring-shaped electrode attached around the rotating unit. It has 6S. The fixed portion 24 has a convex contact terminal 4S that can be electrically connected to the ring-shaped electrode 6S, and transfers electric power or a signal by a so-called slip ring structure. The X-rays 26 emitted from the X-ray generator 25 pass through the subject (not shown) and reach the detector array 31. As will be described in detail below, it is an important issue that the gantry 5, particularly the rotating portion 23, is lightweight in order to reduce the size of the CT device and improve the portability by a vehicle or the like. FIG. 2C is a side view for explaining an example of a rotating structure different from that of FIGS. 2A and 2B with respect to the rotating portion 23. The rotating unit drive motor 19m and the rotating unit 23g are combined by a gear structure without using the rotating unit rotating belt, and the rotational torque of the rotating unit driving motor 19m is transmitted to the gears 19g and the gears on the outer periphery of the rotating unit 23g. The number of teeth of the gear 19g is less than the number of teeth on the outer circumference of the rotating portion 23g. Compared to the structure using a belt, this structure does not have a stricter tolerance (margin) for the displacement of the rotating portion 23g in the Z-axis direction. It is effective when it is used to reduce wear of occasional parts such as ball bearings due to rotation, or to reduce vibration and noise. A direct drive (DD) motor structure may be formed in which the rotating portion 23 is a rotor and the inner circumference of the gantry 5 surrounding the rotor is a stator.

The internal structure of the gantry 5 suitable for the CT apparatus 100 will be described with reference to FIG. As shown in FIG. 3A, the rotating portion 23 and the fixing portion 24 are combined in the vertical direction via a plurality of ball bearings 50 arranged in an annular shape. The rotating portion 23 is rotated by an external motor (not shown) via the timing belt 21. Further, the permanent magnets 34-1 and 34-2 are paired with each other so that the rotating portion 23 and the fixed portion 24 face each other and have the same polarity (that is, the north poles or the south poles face each other). Is arranged (to do). Each of the permanent magnets 34-1 and 34-2 may be a single donut-shaped permanent magnet, or may have a structure in which a plurality of magnets are arranged on the circumference. As the permanent magnet, for example, a neodymium magnet, a samarium-cobalt magnet, a ferrite magnet, or the like can be used. By arranging the permanent magnets in the rotating portion 23 and the fixing portion 24 in this way, magnetic forces repelling each other are generated, and the load applied to the ball bearing 50 by the weight of the rotating portion 23 can be reduced. That is, it is similar to the magnetic levitation method, but does not necessarily have to completely levitate. This is because it is possible to obtain the effect of reducing the starting torque when rotating the rotating portion 23, or reducing the wear of the ball bearing and the generation of noise due to high-speed rotation. Further, the rotating portion 23 can be easily rotated at a high speed of, for example, 2 to 10 rotations per second. The narrower the gap d between the rotating portion 23 and the fixed portion 24, the greater the repulsive force. However, in consideration of the surface processing accuracy of both, for example, it is set in the range of about 0.1 to 5 mm (mm). To.

3 (b) to 3 (e) are partially enlarged views for explaining a modified example using magnetic force repulsion and suction in the broken line portion A in FIG. 3 (a). FIG. 3B has a structure in which magnets having the same polarity face each other, such as S poles or N poles, as already described in FIG. 3A. As shown in the figure, when the rotating portion 23-1 is located above the fixed portion 24-1, the rotating portion 23-1 is lifted in the direction against gravity by the repulsive force between the magnets. FIG. 3C shows a structure in which the S pole and the N pole face each other, and as shown in the figure, when the rotating portion 23-2 is located below the fixed portion 24-2, the rotating portion 23-2 is a magnet. Due to the attractive force of each other, a force that pulls up in the direction against gravity works. FIG. 3D has a structure in which the above FIGS. 3B and 3C are combined, and the fixing portion 24-2 is located above the rotating portion 23-2 and rotates due to the attractive force between the magnets. A force that pulls up the portion 23-2 in the direction against gravity acts. On the other hand, the fixed portion 24-1 is located below the rotating portion 23-2, and the repulsive force between the magnets exerts a force that lifts the rotating portion 23-2 in the direction against gravity. These repulsive and attractive forces can be induced not only by permanent magnets but also by, for example, electromagnets. An embodiment in the case of using such electromagnetic induction will be described with reference to FIG. 3 (e). A magnet 34 is attached to the rotating portion 23-3, and an electromagnet 32 in which a coil 36 is wound around an iron core is attached to a fixed portion 24-3 at a position facing the magnet 34. The magnetic force induced in the electromagnet 32 is controlled by the power supply 42 and the amplifier (Amp.) 46. A gap sensor 44 is attached to control the height of the rotating portion 23-3 in the Z-axis direction. Although it is possible to replace the magnet in FIGS. 3B to 3D with an electromagnet, it is important to suppress an increase in the weight of the entire gantry, particularly the rotating portion 23-1 or 23-2. is there.

The internal structure of the rotating portion 23 suitable for the CT apparatus 100, particularly the electric circuit portion, will be described with reference to FIG. FIG. 4A is a plan view showing components and the like when viewed from the Z-axis direction for explaining the internal structure of the rotating portion 23 inside the gantry 5. Inside the rotating unit 23, there are light sources such as an X-ray generator 25, a light source drive circuit 29, a detector array 31, a detector peripheral circuit 33, a detector drive control circuit 41, and a digital signal processing circuit (not shown). It has a semiconductor image memory 35, a secondary battery 27, and a rotating unit interface 2-2. As described below, the X-ray generator 25, the secondary battery 27, and the semiconductor image memory 35 preferably have a cartridge structure that can be easily inserted and removed individually from the rotating unit 23, respectively. The cartridge and the rotating portion 23 can be electrically conductive by contacting the metal terminals. The rotating unit interface 2-2 may be a non-contact interface described later or an electrical contact with a conductive electrode. The X-ray beam 26 emitted from the X-ray generating unit 25 passes through the subject (not shown) standing along the back plate 3 and reaches the detector array 31. A weight balance adjusting unit for adjusting the weight balance during rotation of the rotating unit may be provided. Preferably, an X-ray generator using a carbon nanomaterial such as carbon nanotube (CNT) as a field electron emission source may be used for the X-ray generator 25. Since the carbon nanomaterial is used as the cold cathode material, preheating is not required, and compared to the case of using a conventional X-ray tube, it is possible to reduce the size and power consumption, and the high voltage control circuit 29 can be downsized and the cooling fan. This is because the size of the cooling fan itself can be reduced or the cooling fan itself can be eliminated. In this embodiment, the structure in which the detector array 31 is built in the rotating portion 23 has been described. However, as will be described later, the detector array 31 is not inside the rotating portion 23 but the rotating portion 23. The structure may be arranged so as to cover the entire inner circumference of the fixed portion of the surrounding gantry 5. In this case, it is not necessary to arrange the detector peripheral circuit, the semiconductor image memory, etc. in the rotating portion in the gantry, and the rotating portion is further reduced in weight.

FIG. 4B is a circuit block diagram for explaining the inside of the rotating portion 23, particularly the detector 31 and its peripheral circuits 33 and the like. The peripheral circuit 33 includes a detector drive control circuit 41, a signal amplification / analog-to-digital (AD) conversion circuit 43, a signal scanning / control circuit 45, a digital signal processing circuit 47, a parallel serial conversion circuit 49, and the like. As shown in the figure, a plurality of detector units 30 are regularly arranged in an arc shape or in the Z-axis direction in order to increase the number of slices in the detector array 31. The detector unit 30 includes a small electron multiplier type detector (for example, "micro PMT element" manufactured by Hamamatsu Photonics Co., Ltd.), an amplification type detector using an avalanche effect (APD), a photomultiplier type detector, and the like. A high-sensitivity detector can also be used. Further, since a CMOS type detector in which an analog-to-digital (AD) conversion circuit, a signal processing circuit, or the like is on-chip can be used, high-speed and low-noise readout can be realized. Since these detector units have high sensitivity or low noise, the amount of X-ray irradiation (exposure) is reduced, or high-speed scanning in the Z-axis direction by short-time pulse irradiation becomes easy. Further, in addition to weight reduction by thinning the rotating portion 23 in the Z-axis direction, it is also possible to improve the stability and durability of the carbon nanomaterial used as a field electron emission source. As will be described later, the detector unit 30 has a structure having a scintillator layer that converts incident X-rays into visible light corresponding to a band gap of a semiconductor material used for the detector unit 30, for example, silicon (Si). May be good.

The detector signal output from the detector array 31 is converted into digital data (for example, 16 bits) by the signal amplification / AD conversion circuit 43, and sent to the digital signal processing circuit 47 via the signal scanning / control circuit 45. The necessary image processing is added. A semiconductor image memory 35 is built in the rotating unit 23 in order to directly record the image data sent from the digital signal processing circuit 47. Since parallel recording can be performed directly in the semiconductor image memory 35 via the bus line 38 without parallel serial conversion, high-speed writing to the semiconductor non-volatile memory becomes possible. As the semiconductor image memory 35, a semiconductor non-volatile memory such as a NAND flash memory is suitable. When the operator of the CT device wants to monitor the CT image in real time, the image data stored in the DRAM, which is a semiconductor image memory, can be displayed on the monitor screen via the wireless communication interface. This is because it is possible to use high-speed, large-capacity communication interface (5G, etc.) technology that has become widespread in recent years. On the other hand, when reading image data from a semiconductor non-volatile memory, for example, the NAND flash memory after the completion of imaging and after the rotation of the rotating unit 23 and the movement of the gantry 5 are stopped, it is not necessary to read the image data in real time unlike the time of imaging. Therefore, the parallel serial conversion circuit 49 may output the serial data to the rotating unit interface 2-2. Serialization also has the effect of reducing the number of terminals in the host interface 2-1. In the electrical connection means including the host interface 2-1 and the rotating part interface 2-2, there are a plurality of connectors inside the rotating part interface 2-2 of the rotating part 23, and the shape thereof is a concave receiving structure ( Concave connection terminal 6). On the other hand, there are the same number of convex connection terminals 4 on the side of the host interface 2-1. By inserting the connection terminals 4 into the concave connection terminals 6, electrical connection is possible. Unlike the case where a slip ring, which is a conventional dynamic mechanical (sliding) contact, is used, the image data recorded and accumulated inside the rotating unit 23 when it is stationary is recorded from the rotating unit interface 2-2 to the host interface 2. Read to -1. Therefore, the harmful effect of using the slip ring can be eliminated, and high-speed rotation of the rotating portion 23, for example, high-speed rotation of 2 rotations or more per second becomes easy. For example, a detector (FIG. 5, etc.) described later will be described as an example. When the number of pixels in the body axis (Z axis) direction of the detector is 500 pixels, the pixel arrangement pitch is 50 micron meters (μm), and the rotation speed of the rotating part is 5 rotations per second, the body axis of the gantry 5 The movement speed in the (Z-axis) direction is estimated to be about 12 cm (cm) / sec. Even if the pixel arrangement pitch is 50 microns (μm) in length and width, a group (10 ×) of a plurality of pixels whose inside is further subdivided, for example, small pixels of 5 μm (μm) square. It may be composed of 10 pixels). This is because high-speed readout conforming to the design rules, pixel thinning, pixel addition, and the like can be facilitated. In this way, by reducing the weight of the rotating portion 23 and increasing the rotation speed, the scanning speed in the body axis (Z-axis) direction can be increased, so that the amount of X-ray exposure can be reduced without increasing the number of slices, and the pixels. In addition to improving the inspection accuracy by miniaturizing the X-ray, it is also effective for photographing constantly moving organs such as the heart.

FIG. 4C is a block diagram for explaining the X-ray generating unit 25 and the light source driving circuit 29 inside the rotating unit 23. The X-ray generating section 25 of the cartridge structure is composed of a carbon nanomaterial electron beam generating cold cathode 25C and an anode target 25A. The light source drive circuit 29 is composed of a voltage booster circuit 29-1 and a high voltage control circuit 29-2. Preferably, the light source drive circuit 29 is a transformerless compact, lightweight, low power consumption high voltage power supply unit by using a switching power supply and a power semiconductor. As the secondary battery 27 having a cartridge structure, for example, a lithium ion battery can be used. In this way, the DC voltage of the lithium-ion battery 27 can be boosted by the light source drive circuit 29, and the timing-controlled high-voltage pulse can be applied to the X-ray generator 25. The lithium-ion battery 27 can be charged via the rotating unit interface 2-2 and the host interface 2-1 when the rotating unit 23 is stationary by using a battery remaining amount detection circuit and a charging circuit (not shown).

FIG. 5A is a plan view of the CT device 200 according to the modified example of the CT device 100, particularly the structure inside the gantry as viewed from the Z-axis direction, and FIG. 5B is a plan view of the CT device 200 according to the modified example of the CT device 200. It is sectional drawing seen from the X-axis or Y-axis direction of the gantry part 5-2 in 1 As shown in FIG. 5A, in this embodiment, an X-ray light source unit 25 m having a cartridge structure, a secondary battery 27 m, a high voltage control circuit 29 m, etc. are built in the rotating unit 23, while the rotating unit A large number of detector units 30 mounted on the entire circumference inside the annular fixing portion 24 having a center at the same position as the rotation center are built in. In this embodiment, the fixing portion 24 is fixed to the outer peripheral portion 5-2 of the gantry and is located inside the rotating portion 23 on the XY plane view. Further, a rotation drive motor 19 and a timing belt 21 for rotating the rotating portion 23 are shown. Further, inside the gantry moving carriage 11, in addition to the rotary drive motor 19, a semiconductor image memory 35 m having a cartridge structure and a detector drive control circuit 41 m are built in. As shown in FIG. 5B, the fixing portion 24 is provided so that the X-rays (broken line arrows) emitted from the X-ray light source portion 25m in the gantry 5-1 are not obstructed by the fixing portion 24. A structure shifted in the Z-axis direction with respect to the mounting position of the detector unit 30 is adopted.

FIG. 5C is a cross-sectional view for explaining the internal structure of the CT device according to the modified example of the CT device 200, particularly the gantry 5-2. A fixed portion 24 and a rotating portion 23 are incorporated in the gantry 5-2. The difference from the structure shown in FIG. 5B is that the diameter of the rotating portion 23 containing the X-ray light source 25 m is smaller than the diameter of the inner peripheral portion of the fixed portion 24, and therefore the X-ray light source 25 m emits light. The X-rays reach the detector 30 without being hindered by the fixed portion 24. However, in the conventional structure, for example, it is necessary to pass a high voltage or a large current from the brush to the slip ring while sliding it at high speed, and not only the contact surface generates heat and causes seizure, but also light emission due to sparks or the like. Due to the phenomenon, the risk of erroneous photoelectric conversion in the detector 30, that is, noise that causes deterioration of image quality is unavoidable. However, in this structure, the rotating portion 23 of the portion facing the central axis of rotation of the X-ray light source 25 m is on the optical path of the X-ray emitted from the X-ray light source 25 m, which hinders uniform X-ray irradiation. there's a possibility that. A structure that solves this problem will be described below with reference to FIG.

FIG. 6A is a plan view of the CT apparatus 300 according to the embodiment as viewed from the Z-axis direction for explaining the structure in the gantry. As described above, the fixing portions 24 are combined so as to surround the outer circumference of the rotating portion 23. A detector (not shown) is arranged on the inner circumference of the fixed portion 24 over the entire circumference. The rotating unit 23 incorporates an X-ray generating unit 25 m, a light source drive circuit (not shown), a secondary battery, and the like. An opening 28 shown by a broken line is formed in the rotating portion 23, and X-rays emitted from the X-ray generating portion can be transmitted or passed through. That is, the influence on the intensity and the traveling direction of the X-ray beam 26 can be reduced. The opening 28 does not necessarily have to have all the members removed (air only), and for example, a protective cover made of resin having high X-ray transmittance, a light-shielding film against visible light, or the like is left. You may be. FIG. 6B is a cross-sectional view of the structure of the gantry 5-2 as viewed from the X-axis or Y-axis direction. The detector 30 is arranged along the inner circumference of the fixed portion 24, and the X-ray 26 that has passed through the opening 28 reaches the detector 30. A fiber optic plate that selectively shields or collimates X-rays, an X-ray scintillator, or the like can be laminated on the upper part of the detector 30.

FIG. 6 (c) is an enlarged view seen from the Z-axis direction for explaining the structure of the portion related to the broken line portion B in FIG. 6 (a). Along the annular portion of the fixed portion 24, the detectors 30 are closely arranged so that the longitudinal direction of the detector 30 is parallel to the Z axis. That is, it is a plan view when the opening 28 is viewed from the X-ray generating portion 25m toward the same portion using FIG. 6D. Since the pixel arrays of the plurality of detectors 30 attached to the fixed portion 24 are exposed to the X-ray light source 25 m by the opening 28 formed in the rotating portion 23, the irradiation X-rays can be detected without being shielded. It enables X-ray exposure to the vessel 30.

With reference to FIG. 7, the structure of the detector 30 suitable for use in the CT device 200, the CT device 300, and the like, and the arrangement and combination thereof will be described below. FIG. 7A shows a structure in which a plurality of detectors 30-1 are closely arranged along the inner circumference of the fixing portion 24 so as to surround the rotation center axis 1. As shown in the figure, the detector 30-1 includes a vertical shift register 30-12, a horizontal shift register, a signal reading circuit 30-13, and the like along two opposite sides of a light receiving region in which a large number of pixels 30-11 are arranged. The peripheral circuits of the above are arranged, and the remaining two opposite sides are the ends of the light receiving region. The boundary line in which the plurality of detectors 30-1 are in contact is 30-14, and the arrangement pitch of each pixel 30-11 sandwiching this boundary line is inside the light receiving region that does not touch the boundary line 30-14 in the same direction. It is desirable that it is equal to the arrangement pitch of pixels 30-11. As shown in the figure, the plurality of detectors 30-1 have the above peripheral circuits formed along two sides where the detectors 30-1 are not adjacent to each other. This is to obtain a continuous pixel signal in the rotation direction of the rotating portion. It is desirable that the element size of the detector 30-1 is large, but for example, the so-called medium format size (44 mm × 33 mm), full size (36 mm × 24 mm), which are widely used in digital cameras and the like. The structure and manufacturing method of the CMOS type image sensor such as APS size (23 mm × 15 mm) can be diverted, or the design suitable for the structure of the CT apparatus of the present invention can be used.

In FIG. 7B, a plurality of detectors 30-2 are closely arranged along the inner circumference of the fixing portion 24 so as to surround the rotation center axis 1, and further detect in the direction of the rotation center axis 1. Disclosed is a structure in which the number of pixels in the body axis (Z axis) direction is increased by arranging the device 30-2. As a result, the slice width can be expanded about twice. In this embodiment, the boundary line 30-24 of the detector 30-2, which is in close contact with the left and right sides, is important in the drawing. This is because it is desirable that the arrangement pitch of each pixel 30-21 having a boundary line sandwiching 30-24 equal to the arrangement pitch of other pixels 30-21 that do not touch the boundary line 30-24 in the same direction. Further, as shown in the figure, the horizontal and vertical scanning circuits and the signal readout circuits ((30-22, 30-23) have the arrangement pitch of each pixel 30-11 on the three sides of the detector 30-2 as described above. In order not to interfere with the circuit, the circuit is arranged on one side of the detector 30-2.

FIG. 7 (c) is a cross-sectional view for explaining the structure of the detector 30-2 shown in FIG. 7 (b). The detector 30-2 is a CMOS type solid-state image sensor having a back-illuminated structure, and a scintillator layer 39 is laminated on the back surface side. It is sufficient that the thickness of the silicon substrate used in this CMOS type solid-state image sensor is about 5 to 10 microns (μm). This is because the incident X-rays are converted into visible light in the scintillator layer and then read out as an electric signal via the pixel 30-21. The wiring layer 30-26 is arranged on the front side of the detector 30-2, and the horizontal and vertical scanning circuits, signal readout circuits ((30-22, 30-23), and connection terminals 30-25) are arranged in the area C surrounded by the broken line. On the back surface side, a shielding member 40 for protecting and mitigating the integrated circuit from X-ray damage is arranged above the area C (30-22, 30-23).

The CT apparatus 400 according to the embodiment will be described with reference to FIG. Although the Z-axis is shown in the horizontal direction for convenience of drawing arrangement, when the CT device 400 is used, it is used in a state of being rotated 90 degrees so that the Z-axis is vertical. FIG. 8A is a side view of the CT device 400 as viewed from the X-axis direction. The CT device 400 is composed of columns 7-1 and 7-2, a ceiling portion (9-3) of the CT device 400, and a bottom portion (9-4) on which the subject rides. Since the ceiling portion (9-3) has the functions described below, it can also be called a cradle. In addition, the bottom (9-4) on which the subject rides can also be called a cradle or a stage on which the subject rides. It has a structure in which a gantry 5 that can move in the Z-axis direction is attached between the ceiling portion (9-3) and the bottom portion (9-4) on which the subject rides. Inside the gantry 5, there is a rotating portion 23 that can be rotated by a rotary drive motor 19, and the rotation central axis 1 thereof is shown in the drawing. A cartridge structure component (not shown) is used inside the rotating portion 23. It has wheels 15 and a gantry traction motor 14 for moving the gantry 5 in the Z-axis direction. Further, as described in detail below, the electrical connection means 10 for exchanging an electric signal or electric power with the rotating portion 23 in the gantry is connected to the gantry storage portion 37 of the cradle 9-3 with the electrical connection means 12 Are arranged in the rotating portion 23 in the gantry so as to face each other with the electrical connecting means 10. These can supply non-contact power in a state of facing each other and close to each other, for example, charging a lithium ion battery or the like inside the rotating unit 23, or exchanging data or a signal between the rotating unit 23 and the cradle side. it can. The back plate 3 that determines the position of the subject is inserted in the hollow portion of the gantry 5 in the Z-axis direction. During the imaging, only the gantry 5 moves in the Z-axis direction, and the subject is stationary together with the back plate 3. It should be noted that there is an operation / control unit and a display (monitor) unit (not shown), and a tomographic image or the like reconstructed by an image drawing circuit or software is displayed on the monitor.

Further, in addition to the non-contact host interface 10 described above, a sample holding portion 20 is provided inside the gantry storage portion 37 of the cradle 9-3. The sample is, for example, an object to be measured for preliminarily testing whether or not the detector and the light source unit inside the rotating unit 23 are functioning normally, and is called a standard sample or a phantom. Further, an inspection probe (not shown) for the purpose of inspection or calibration of the rotating portion 23 may be provided in the cradle. Alternatively, inside the storage portion 37, there is a supply port 16 for cooling gas, for example, air or nitrogen gas, in order to lower the temperature inside the gantry 5, while the rotating portion 23 fits into the supply port 16. An opening 18 provided in the rotating portion 23 is provided. Further, by providing a hold mechanism (not shown) for holding and fixing the gantry, the gantry portion can be protected from impact even when the CT device is moved by a vehicle or the like and used at a destination. In this way, the cradle 9-3 can be provided with functions necessary for stable driving of the gantry or maintenance such as safety and performance.

FIG. 8B is a block diagram for explaining an example of a circuit configuration related to electromagnetic induction type wireless power feeding in the non-contact interface units (10 and 12). As shown in the figure, the circuit configuration of the interface 10 on the cradle side consists of an AC / DC converter (10-3) that converts commercial power (10-2) to direct current, and a high-frequency inverter (10-4) that outputs high-frequency square waves. ), A waveform conversion circuit (10-5) that converts this into a sinusoidal wave, an isolation transformer (10-6) for ensuring safety, and the like are connected to the primary coil L1 (10-1). On the other hand, the secondary coil L2 (12-1) is loaded with a load such as a secondary battery (12-2) via a rectifying smoothing circuit (12-4) that returns high frequencies to direct current, a backflow blocking diode ((12-3), etc.). ) Etc. On the other hand, a wireless communication method (not shown) based on near-field magnetic field coupling is used for transmitting and receiving control signals or image data, etc., and is rapidly becoming widespread in recent years. It is also possible to transmit high-speed, large-capacity CT image data using a high-speed, large-capacity communication method (for example, 5G) because the data transfer speed can be increased by giga (G) bits / second or more. There may be a method in which the wireless power supply and the wireless communication are performed using the same coil or antenna.

A method of driving the CT device 400 according to the embodiment will be described. After the movement of the gantry 5 and the start of rotation of the rotating portion 23, imaging by X-ray irradiation is started. The digital data obtained from the detector array 31 is recorded in the semiconductor image memory in real time. As described with reference to FIG. 2B, the digital data can be recorded in the image memory (35) as it is without the need for parallel serial conversion. After the imaging is completed, the gantry stops at a predetermined position, the data recorded in the image memory 35 is read from the rotating unit interface 12 via the clay-side interface 10, and after the image reconstruction process in the operation / control unit, the gantry is reconstructed. It is displayed on the monitor and returns to the standby state. At the same time, or during standby, the lithium ion battery (27) is charged to complete a series of imaging drive sequences.

8 (c) and 8 (d) are cross-sectional views for explaining the structure of the gantry portion 5 and the cradle 9-5 according to the modified example of the CT device 400. That is, it discloses a structure capable of shortening the apparent charging time of the secondary battery in the gantry while the gantry section 5 is retracted to the cradle section 9-5. As shown in FIG. 8C, the secondary battery is a secondary battery 27 m having a cartridge structure and is inserted into the insertion space 27f. On the other hand, the gantry storage portion 37 of the cradle 9-5 is provided with a cartridge holder 22, and when the gantry 5 is stored in the gantry storage portion 37, the secondary battery 27m is coupled to the cartridge holder 22. After that, when the gantry 5 separates from the gantry storage unit 37, the secondary battery 27 m remains in the gantry storage unit 37, and charging is performed. FIG. 8D is a cross-sectional view of the rotating portion 23 in FIG. 8C when the rotating portion 23 is rotated 90 degrees about the central axis 1. The secondary battery 27m is not inserted in the second secondary battery insertion space 27f inside the gantry 5, while the cartridge holder 22 inside the gantry storage portion 37 of the cradle 9-4 is charged. The next battery 27m is attached. Therefore, when the gantry 5 is stored in the gantry storage unit 37, the charged secondary battery 27 m can be inserted into the secondary battery insertion space 27f in the gantry. In other words, by returning the used secondary battery 27m to the cradle 9-4 and at the same time inserting the charged secondary battery 27m into the gantry 5, it is not necessary to wait for the used secondary battery 27m to be fully charged. When the gantry unit 5 receives the charged secondary battery, the next imaging operation can be started immediately. As a result, the apparent charging time of the secondary battery can be shortened or eliminated, the time required for inspection can be shortened, and the operating efficiency of the device can be improved.

9 (a) and 9 (b) are side views of the medical inspection vehicle 600 and the medical inspection vehicle 700 according to the embodiment, respectively. In this figure, the height direction of the vehicle, that is, the vertical direction coincides with the Z axis of the CT device 100. In this figure, the CT device 100 is described for simplification of the description, but any of the CT devices 200 to 400 already described may be used. The same applies to FIG. In the inspection vehicle 600 in FIG. 9A, the CT device 100 is located behind the inspection vehicle, and the subject can enter the CT device by opening the door 48 provided on the rear side surface of the vehicle. On the other hand, in the case of the inspection vehicle 700 shown in FIG. (B), the door 48 is provided on the left or right side surface of the vehicle, and the subject can enter the CT device from either the left or right side surface of the vehicle. In both cases of FIGS. 9A and 9B, a solar panel 13, a staircase or a step 17 is provided.

9 (c) and 9 (d) show XY plan views when the

inspection vehicles

600 and 700 are viewed from above. In the case of the inspection vehicle 600 (c), as described above, the subject can directly enter the CT device 100 arranged in the section 63-3 in the inspection vehicle 600 from the rear part of the vehicle. On the other hand, in the case of the inspection vehicle 700 (d), the subject can directly enter the CT device 100 arranged in the section 63-3 in the inspection vehicle 700 from the side surface of the vehicle. In either case, the subject shall be examined by a CT device without going through other examinations and examination areas (63-1, 63-2, etc.) other than the waiting room and changing room, and the in-car passage 64, etc. Can be done. Therefore, even for a subject suspected of having an infectious disease or the like, it becomes easy to reduce the risk of infecting a medical worker or a patient in a vehicle with a virus or a bacterium. More preferably, the atmospheric pressure of the section (63-3) where the CT device 100 is installed or the place where the subject is located is set from the atmospheric pressure of other examination or examination sections (63-1, 63-2, etc.) or the passage 64 in the vehicle. The risk of infection can be further reduced by keeping the pressure low (negative pressure). For that purpose, for example, by providing a forced ventilation means (ventilation fan, etc.) to the outside of the vehicle in the section (63-3) where the CT device 100 is installed or in the place where the subject is present, another examination or examination section (63-). 1, 63-2, etc.) and the structure will be lower than the air pressure in the in-vehicle passage 64.

FIG. 10A is a block diagram of a main part for explaining the power supply configuration of the medical vehicle 800 according to the embodiment, particularly centering on the vehicle drive motor 77, the CT device 100, and the like. The medical vehicle 800 includes a hydrogen storage tank 75, and uses hydrogen gas to supply the electric energy generated in the fuel cell 73 to the vehicle drive motor 77. Further, it has a vehicle regenerative braking circuit 79 that recovers the regenerative energy associated with the moving vehicle braking of the medical vehicle 800, that is, the deceleration. The main power source of the CT device is supplied from the fuel cell 73 via the cradle 7. Further, while the medical vehicle 800 is moving, the secondary battery inside the gantry 5 can be charged from the vehicle regenerative braking circuit 79 via the cradle 7, for example. In addition, the solar panel 13 makes it possible to use solar energy and charge the lithium ion battery 74 and the like inside the vehicle. The fuel cell 73 consumes only hydrogen (H2) and air (Air), and emits only water (H2O). Therefore, there is no problem of harmful exhaust gas, noise, vibration, etc., and there is an advantage that medical activities such as medical examination can be continued without harming the subject, medical staff, and the like.

In the above-described embodiment relating to the medical vehicle, the structure in which the part for performing the inspection or medical treatment and the part for driving the vehicle are integrated has been described, but as shown in FIG. 10B, the vehicle for performing the inspection or medical treatment Needless to say, the structure may be such that the 910B is towed by another movable vehicle 910A. In this case, the vehicle 910B for performing the inspection or medical practice may have a method of receiving power supply from the driving movable vehicle 910A, or a structure in which a power supply unit such as a fuel cell is built in the vehicle 910B. With this structure, after arriving at the destination, the driveable vehicle 910A can separate the vehicle 910B performing the inspection or medical treatment, and tow the vehicle performing another inspection or medical treatment to go to another destination.

The

medical vehicle

800 or 900 facilitates inspections, medical activities, etc. by going to remote areas, areas affected by earthquakes, typhoons, etc., developing countries, and other places where power supply and refueling cannot be expected. In such an environment, it is often expected that the

medical vehicle

800 or 900 will be moved into an outdoor tent or inside a building such as an evacuation center to continue examination and medical treatment activities for 24 hours. This is because the energy efficiency of the fuel cell 73 is high, and the spare hydrogen storage tank enables the continuation of medical activities for a long time. Further, as shown in the flowchart of FIG. 10C, the fuel cell 73 mainly supplies electric power to the vehicle drive motor 77 after the medical vehicle 500 starts moving and before using a medical device such as a CT at the destination. However, there is no need to supply electric power to medical devices such as CT devices. On the other hand, after the

medical vehicle

800 or 900 is stopped at the destination, the fuel cell 73 mainly supplies electric power to medical equipment such as a CT device, and it is not necessary to supply electric power to the vehicle drive motor 77. Further, while the

medical vehicle

800 or 900 is moving, the secondary battery or the like built in the CT device can be charged from the vehicle regenerative braking circuit 79.

Different medical fields such as orthopedics, cardiology, gastroenterology, etc. and different by replacing the gantry part, the light source part and the detector cartridge, or adding the gantry for PET or the gantry using near infrared light as the light source. Multi-imaging diagnosis for light source energy is realized in one CT device. In addition to medical applications for humans, it can be widely used for animal and plant inspections, industrial measurements, and the like.

Claims

A CT device having a gantry with a built-in rotating portion that rotates about the body axis direction, the central axis being in the vertical direction, and the rotating portion and a fixed portion surrounding the rotating portion being combined in the vertical direction. , A CT device in which magnets or electromagnetic guiding means for generating a magnetic field are arranged close to each other at positions where the rotating portion and the fixed portion face each other.
The first aspect of claim 1, wherein the rotating portion is located above the fixed portion at the facing position, and magnets are attached to the rotating portion and the fixed portion so that the same polarities face each other at the facing position. CT device.
The first aspect of claim 1, wherein the rotating portion is located below the fixed portion at the facing position, and magnets are attached to the rotating portion and the fixed portion so that different polarities face each other at the facing position. CT device.
The CT according to claim 1, wherein the rotating portion is located above the fixed portion at the facing position, the rotating portion has a magnet at the facing position, and an electromagnetic induction means is arranged at the fixed portion. apparatus.
The CT according to claim 1, wherein the rotating portion is located below the fixed portion at the facing position, the rotating portion has a magnet at the facing position, and an electromagnetic induction means is arranged at the fixed portion. apparatus.
The CT apparatus according to claim 1, further comprising a drive motor that rotates the rotating portion and a timing belt that transmits the rotational torque of the drive motor to the rotating portion.
The CT according to claim 1, wherein a gear structure having different numbers of teeth for transmitting the rotational torque of the drive motor that rotates the rotating portion to the rotating portion is provided on the rotating shaft of the driving motor and the circumference of the rotating portion. apparatus.
The CT device according to claim 1, wherein at least a light source, a light source drive control circuit, and a secondary battery for driving these are built in the rotating portion.
The CT apparatus according to claim 8, wherein a detector and a semiconductor image memory for recording an output signal of the detector are built in the rotating portion.
The CT apparatus according to claim 8, further comprising a detector on the inner circumference of the fixed portion facing the outer peripheral portion of the rotating portion.
The tenth aspect of the present invention, wherein the rotating portion has an opening that is a portion of the light source that faces the rotation center of the rotating portion and that allows the light emitted from the light source to pass through and exposes the light receiving surface of the detector. CT device.
The CT according to claim 9 or 10, wherein the longitudinal direction of the peripheral circuit block formed on the same semiconductor substrate of the detector is parallel to the normal direction of the circumference having the central axis as the rotation axis. apparatus.
The CT apparatus according to claim 9, wherein the light receiving surface of the detector is curved about the central axis.
The CT apparatus according to claim 8, wherein the light source is an X-ray light source, and the electron beam generating portion of the X-ray light source is composed of carbon nanostructures.
The CT apparatus according to claim 1, wherein the gantry moves in the central axis direction.
The light source according to claim 8, the secondary battery, or the detector according to claim 9, or the semiconductor image memory has a cartridge structure, and the rotating portion has a light source and a secondary having the cartridge structure. The CT apparatus according to claim 8 or 9, further comprising a cartridge opening for inserting or removing a battery, a detector, or a semiconductor image memory individually.
An inspection vehicle equipped with a CT device, which has a gantry containing a rotating portion that rotates about the body axis direction of the CT device, the central axis of which is in the vertical direction, and a subject to the CT device. An inspection vehicle whose entrance is on a surface parallel to the central axis and is located on a side surface or a rear side surface of the inspection vehicle.
The inspection vehicle according to claim 17, which is equipped with the CT device according to any one of claims 1 to 16.
The inspection vehicle according to claim 17, wherein the air pressure in one section occupied by the CT device inside the inspection vehicle is lower than the air pressure in the other sections inside the inspection vehicle and the moving passage.
The inspection vehicle according to claim 17, wherein the power source for driving the CT device is a fuel cell using hydrogen gas.