JP6820989B1 - Imaging device and its driving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate movement and installation of an imaging device such as an X-ray CT by downsizing, weight reduction and power consumption, and to reduce a maintenance load such as repair / replacement of used parts. SOLUTION: A light source, a detector, an image memory 35 m, a secondary battery 27 m, and other parts built in a rotating portion 23 in a gantry have a detachable cartridge structure, and the cartridge is placed in the rotating portion in the direction of the central axis 1. Alternatively, the CT apparatus 200 is provided with a cartridge accommodating portion having an opening for inserting or removing from the central axis in the normal direction in the rotating portion. [Selection diagram] Fig. 3

Description

The present invention relates to an imaging device such as a computer tomography device, a driving method thereof, and a medical examination vehicle equipped with these.

An image pickup device, for example, an X-ray computer tomography (CT) device, advances or retracts a gantry including a rotating part that rotates around an object to be imaged, and a bed on which a subject is placed so as to pass inside the gantry. It is composed of a sleeper moving device, a slip ring that enables electrical connection with a rotating unit, an operation and a monitor unit including an image drawing unit that processes image data transferred to the outside via the slip ring, and the like. 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 conditioning equipment, 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 (Patent Documents 1 to 6).

JP-A-61-244330 JP-A-2-224746 JP 2001-258873 JP 2005-516343 JP-A-4-22100 JP-A-11-188029 JP 2016-107062

By reducing the size and price of CT equipment such as X-ray CT, it 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. In addition, even in developing countries, other remote areas and depopulated areas, by providing the latest and high-level medical services, we will eliminate medical disparities resulting from natural disasters and regional conflicts. The problems to be solved will be described in detail below.

Various unsolved technical problems remain as factors for increasing the size or cost of CT equipment, and no effective breakthrough has yet been found. One of the factors that hinders the miniaturization of conventional CT devices is that it is difficult to reduce the size and weight of the gantry. The inner diameter of the rotating portion in the gantry is required to have an inner diameter dimension that allows the human body to move and pass in the body axis direction with a margin, for example, an inner diameter of 80 cm or more. The outer diameter of the gantry exceeds 100 cm because it is equipped with an X-ray source and a detector. Further, a structure in which a detector, a detector signal processing circuit, an X-ray source, an X-ray source drive control circuit, an air cooling fan, and the like rotate in a gantry is common. 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 1 to 2 rotations per second on a circumference having a diameter of 80 cm or more. It is necessary to suppress vibration, noise, etc. associated with rotation and minimize the harmful effects on the entire device. Furthermore, in order to move the subject in the axial direction, it is necessary to move the sleeper on which the subject is placed forward or backward at a predetermined speed. Considering the diversity of subjects, that is, the range of body weight (for example, several kilograms to 200 kilograms), the bed moving means must also ensure robustness and stable movement of the bed to cover such a weight range. The whole will be larger and heavier. Therefore, it hinders the practical application of a small medical examination vehicle equipped with such an advanced medical diagnostic imaging device of a CT device.

Further, the detector or the like rotates inside the gantry at a speed of about 1 to 2 rotations per second around the body axis direction. Therefore, in order to read the output signal of the detector or the like to the outside, the signal is transmitted / received or the electric power is exchanged by a mechanical contact means called a slip ring. In order to ensure the electrical connection by the slip ring, it is necessary to keep the rotation speed low and reduce the number of output signal lines from the detector. 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 addition, the structure is shifting to a structure in which the slice width is widened so that a wide area can be exposed by one X-ray pulse irradiation. As a result, in addition to increasing the weight of the gantry, it is inevitable that the X-ray generator will be increased in size. In addition, it is necessary to expand the light receiving area (that is, the number of slices) in the body axis direction, which increases the light receiving area or the number of pixels of the detector used, and further speeds up and large-capacity data transmission and to an external recording medium. High-speed real-time recording is required. For example, when the number of slices is 64, a data processing speed of 1 Gbytes / sec or more is required. In order to record a large amount of data at high speed in real time, for example, a measure is taken to use a combination of multiple hard disks such as RAID (Redundant Arrays of Independent Disks), but the recording speed is about 800 Mbytes / sec. For the following reasons, it is necessary to consider some kind of data compression.

Regarding the transfer of electric power, the supply of electric power to an X-ray source or the like becomes a problem. 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. 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 indispensable. As described above, it is difficult to reduce the size and weight of the sleeper and the gantry part for moving the subject, and it is difficult to carry out the mobile medical treatment using the CT device.

Furthermore, new design specifications are required for the strength of the building and floor for installation, or for dedicated power supply equipment including air conditioning equipment. In this way, the cost of introducing a CT device is not only the cost of introducing the device itself, but also the construction cost required for the building, air conditioning, power supply equipment, etc., and the maintenance of the temperature and humidity of the device and the entire building throughout the year. It is necessary to consider the cost burden such as management costs and regular maintenance costs. In particular, when operating a CT device outdoors or in a remote location, a stable supply of commercial power cannot be obtained, and it is necessary to cope with a usage environment premised on battery drive. In addition, there are cases where we have to rely on solar power and other natural energy, and not only the reduction of power consumption of the CT device itself but also the reduction of energy loss is one of the problems to be solved.

In this way, it is a problem to be solved by the present invention that the CT device is made smaller and lighter, the power consumption is reduced, and the CT device is made more versatile (hybrid), repaired, or the periodic maintenance load is reduced. is there.

A light source, a detector, an image memory that records the output signal of the detector, or a secondary battery installed inside a rotating part that rotates around the body axis in the gantry of the CT device has a cartridge structure. The rotating portion is provided with a cartridge accommodating portion having an opening in the rotating portion for inserting or removing the cartridge in the direction of the central axis or in the normal direction from the central axis. Also, the number of cartridge storage units should be larger than the number of cartridges to be inserted.

A CT device having a sleeper device for guiding a subject into a hollow portion of a gantry. Alternatively, the CT device has a gantry on which the gantry is placed, and a drive unit for moving the gantry in the direction of the central axis on the gantry.

Record the light source, the light source drive control circuit that drives and controls the light source, the detector, the detector that drives the detector, and the detector drive circuit and signal processing circuit that processes the output signal of the detector, and the output signal of the detector inside the rotating part. A host that has a built-in image memory and a secondary battery for driving these, and also has a rotating part interface in the rotating part, and a signal or power transfer to and from the rotating part interface on the inner circumference of the fixed part surrounding the rotating part. A CT device having an interface.

A light source, a light source drive control circuit that drives and controls the light source, and a secondary battery for driving these are built in the rotating part, the rotating part has a rotating part interface, and detection is performed along the inner circumference of the fixed part. It has a detector drive circuit and a signal processing circuit that drives a device and a detector and processes the output signal of the detector, and further has a host interface that sends and receives signals or power to and from the rotating part interface in the fixed part. It is a CT device.

A CT device having an opening for transmitting light emitted from the light source at a portion of the light source facing the rotation center of the rotating portion.

A CT device having a cradle on the upper part of the gantry and a host interface on the cradle.

The detector is a CT device that uses either a photomultiplier tube type detector, an avalanche diode type detector, or a photon counting type detector.

It is a CT device that electrically connects the rotating unit interface and the host interface by mechanically contacting each other at a predetermined position.

The CT device 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.

A CT device having a wireless interface in any of the gantry, the gantry, or the cradle for transmitting and receiving control signals for controlling the movement of the gantry or the sleeper in the body axis direction or the imaging operation of the gantry by wireless communication.

A CT device in which 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.

An induction coil is placed along the annular portion of the rotating part, and a permanent magnet is placed along the fixed part of the gantry that surrounds the rotating part, so that the moment of inertia of the rotating part induces an electromotive force in the induction coil. A CT device having a regenerative brake circuit for converting and storing electricity in a rotating portion. A CT device having an electric double layer capacitor in the regenerative braking circuit is preferable.

The rotating part inside the gantry is composed of two parts, one rotating part is equipped with a timing belt, and the other rotating part has a structure that mechanically interlocks with one rotating part by a ratchet structure. , A claw is attached around one rotating part, and by being caught in a groove on the inner circumference of the other rotating part, torque is transmitted to the other rotating part, and when one rotating part rotates in the opposite direction, The claw is a CT device having a ratchet structure in which torque cannot be transmitted over the groove on the inner circumference of the other rotating portion and the other rotating portion idles.

A CT device whose body axis direction is vertical.

The rotating part and the fixed part in the gantry are combined in the vertical direction via a plurality of ball bearings, and the rotating part is rotated by an external motor via a timing belt, and the rotating part and the fixed part face each other. The permanent magnets are paired, and the CT devices are arranged so that the same polarities face each other.

It is assumed that the examination vehicle is equipped with a CT device having a subject insertion opening on one side surface of the examination vehicle.

The examination vehicle is equipped with a CT device having openings for inserting or carrying out the subject on the side surfaces of both sides of the examination vehicle.

A medical examination vehicle equipped with a CT device whose body axis direction is vertical.

This is a driving method of a CT device in which a cartridge inside a rotating portion is removed when the gantry is retracted to the cradle portion, and a replacement cartridge is removed and then inserted into the cartridge storage portion.

The cartridge inside the rotating part is removed, and the cartridge for weight balance adjustment is inserted into the cartridge storage part after the removal, which is a driving method of the CT device.

After starting to move in the direction of the central axis of the gantry or sleeper, the optical signal transmitted through the subject is converted into an electrical signal by the detector, and the rotating part is rotated while recording the electrical signal in the image memory to rotate the central axis of the gantry or sleeper. It is a driving method of a CT device that stops the movement in a direction at a predetermined position and reads out an electric signal recorded in an image memory.

After the movement of the gantry or sleeper in the axial direction and the rotation of the rotating part start, imaging by X-ray irradiation is started, and after the imaging is completed by the movement of the gantry or sleeper in the axial direction, the image of the gantry or sleeper in the axial direction It is an imaging method in which the moving direction of movement is reversed and imaging is performed by moving the gantry or the bed, and the driving method of the CT device is characterized in that the rotation direction of the rotating portion is reversed after the reversal.

After the rotation of the rotating part starts, the movement of the gantry or the sleeper is started, the imaging of the subject by X-ray irradiation is started, the digital data obtained from the detector array is recorded in the image memory in real time, and after the imaging is completed, The driving method of the CT apparatus is characterized in that the rotational kinetic energy of the rotating portion is converted into the counter electromotive force of the induction coil, recovered as electric energy, and the capacitor or the secondary battery is charged.

After one rotating part starts rotating in the direction in which torque is applied to the other rotating part, the gantry or sleeper starts moving, imaging by X-ray irradiation is started, and the digital data obtained from the detector is stored in the image memory in real time. After the imaging is completed, the rotational torque of one rotating part is reduced or stopped, the coupling with the other rotating part is released, and the rotational motion energy is transferred to the induction coil by the regenerative braking circuit inside the other rotating part. It is used as a driving method of a CT device that converts it into countercurrent power and recovers it as electric energy to decelerate and stop the rotational movement of the other rotating portion while charging the capacitor or the secondary battery.

According to the present invention, since the components in the gantry, for example, the X-ray source, the X-ray detector, the secondary battery, etc. have a cartridge structure, the gantry itself does not need to be disassembled and repaired, and only the defective part is used. By simply extracting and inserting new components, the time and cost required for repairs can be significantly reduced. In addition, in a structure that does not require slip rings or brushes, the frequency of regular parts replacement and maintenance is reduced, and as a result, annual maintenance costs and equipment downtime to maintain optimum equipment performance at all times are reduced. Can be significantly reduced. Furthermore, the size and weight of the imaging device can be reduced and the power consumption can be reduced, and the construction cost of the space for installing the imaging device, the building and the power supply, the air conditioner, etc. can be significantly reduced. In addition, the introduction of energy harvesting technology using a regenerative braking circuit has made it possible to realize an environment-friendly CT device. In addition, since a highly sensitive detector can be used, it becomes easy to reduce the radiation exposure dose of the subject. In particular, even when the number of rotations of the rotating part in the gantry is increased to perform high-speed scanning, the rotational moment of the rotating part after the end of shooting is converted and recovered into electrical energy, and the next shooting, that is, the rotational motion. At the start of, the recovered electrical energy can be reused. As a result, for example, it is possible to reduce the size of the secondary battery built in the rotating portion, shorten the charging time, or increase the number of times of shooting after charging. In addition, various X-ray diagnostic imaging devices, CT, PET, etc. in the fields of orthopedics, cardiology, and gastroenterology will be installed by replacing only the gantry section or the light source section and detector module according to the purpose. Needless to say, one hybrid imaging device according to the present invention realizes various diagnoses in different medical fields. In addition, even in the operating room or inpatient ward in a hospital, the doctor quickly decides the initial diagnosis and treatment policy at the bedside without moving the emergency patient or critically ill patient brought in due to an accident etc. to the examination etc. It becomes easy. In this way, in addition to reducing the size and weight of the image pickup apparatus and reducing the power consumption, the load of repair and maintenance can be reduced. As a result, CT that can be moved by a vehicle or the like is realized, and quick and accurate initial diagnosis in a remote place or a disaster-occurring area becomes possible.

(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 side view of the image pickup apparatus 100 according to the embodiment seen from the X-axis direction, (b) is a plan view also seen from the Z-axis direction, and (c) is surrounded by a broken line in FIG. 1 (a). It is an enlarged view of the part A. (A) is a cross-sectional view of the image pickup apparatus 200 according to the embodiment, particularly the rotating portion 23, as viewed from the X-axis direction. (B) is a cross-sectional view of the image pickup apparatus 210 according to the embodiment, particularly the rotating portion 23, as viewed from the X-axis direction. (C) is a plan view seen from the Z-axis direction for explaining the structure of the gantry portion of the image pickup apparatus 800. (A) is a side view of the image pickup apparatus 300 according to the embodiment seen from the X-axis direction, (b) is a plan view also seen from the Y-axis direction, and (c) is a plan view also seen from the Z-axis direction. It is a figure. (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. (C) and (d) were attached to the cartridge holder 22 from the X-axis direction before the secondary battery (27 m) having a removable cartridge structure was coupled to the cartridge holder 22 in the cradle. 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) is a plan view of the gantry portion of the image pickup apparatus 500 as viewed from the Z-axis direction. (B) is a cross-sectional view seen from the X-axis or Y-axis direction for explaining the structure of the gantry 5-2 of the image pickup apparatus 500. (C) is a cross-sectional view seen from the X-axis or Y-axis direction for explaining the structure of the gantry 5-2 of the image pickup apparatus 510. (A) is an XY plan view of the image pickup apparatus 600, particularly the gantry portion seen from the Z-axis direction, (b) is a cross-sectional structure view also seen from the X-axis or the Y-axis direction, and (c) is FIG. 7. It is an enlarged view of the part B surrounded by the broken line in (a). (D) is a plan view when the opening direction is viewed from the X-ray source 25 m in order to explain the opening 28 formed in the rotating portion 23, and is a detector unit arranged in the fixed portion 24 in the opening. A part of 30 is visible. (A) is a flowchart for explaining the driving method of the image pickup apparatus of this invention. (B) is a conceptual diagram for explaining a spiral locus relative to a subject of a light source unit such as an X-ray generating unit when the gantry or the bed moves in the Z-axis direction while the rotating unit 23 rotates. In (c), X-ray generation occurs when the movement direction of the gantry or sleeper in the Z-axis direction is reversed after the movement of the gantry or sleeper in the Z-axis direction, and the rotation direction of the rotating portion 23 in the gantry is also reversed for imaging. It is a conceptual diagram for demonstrating the spiral locus relative to the subject of a light source part. (D) is an X-ray when the movement direction of the gantry or the sleeper in the Z-axis direction is reversed after the movement of the gantry or the sleeper in the Z-axis direction, and the rotation direction of the rotating portion 23 in the gantry is not changed. It is a conceptual diagram for demonstrating the spiral locus of a light source part such as a generation part relative to a subject. (A) It is a top view of the rotating portion inside the gantry 5 of the image pickup apparatus 700 according to the embodiment as viewed from the Z-axis direction. (B) and (c) are partially enlarged views for explaining electromagnetic induction in the outer circumference of the rotating portion 23 in the broken line portion 39 in (a) and the inner circumference of the gantry 5 surrounding the rotating portion 23. (D) is a circuit configuration diagram for explaining the inside of the rotating portion 23 inside the gantry of the image pickup apparatus 700, particularly the regenerative brake 50. (A) is a plan view of the internal structure of the image pickup apparatus 800 according to the embodiment, particularly the gantry 5, as viewed from the Z-axis direction. (B) is a partially enlarged view (39R) for explaining an example of the ratchet mechanism in the rotating portions 23-1 and 23-2. (C) and (d) are flowcharts for explaining the driving method of the image pickup apparatus when the regenerative brake, the ratchet mechanism and the like are used respectively. (A) is a side view of the image pickup apparatus 900 according to the embodiment as viewed from the X-axis direction. (B) is a perspective view of the image pickup apparatus 1000 according to the embodiment, and (c) is a cross-sectional structure view of the gantry portion 5 of the image pickup apparatus 1000 as viewed from the X-axis or Y-axis direction. (A) is a side view of the medical examination vehicle 1100 according to the embodiment, and (b) is a side view of the medical examination vehicle 1200 according to the embodiment. (C) is a plan view of the medical examination vehicle 1100 viewed from above (Y-axis direction), and (d) is a plan view of the medical examination vehicle 1120 viewed from above (Y-axis direction).

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. The internal structure of the rotating portion 23 of the CT apparatus, particularly the electric circuit portion, will be described in detail with reference to FIG. FIG. 1A 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, a light source, for example, an X-ray generating unit 25 m, a high voltage control circuit 29, a detector array 31, a detector peripheral circuit 33, a detector drive control circuit 41, and a digital signal processing circuit described later (shown). It has an image memory of 35 m, a secondary battery of 27 m, and a rotating part interface 2-2. The X-ray generating unit 25 m, the secondary battery 27 m, and the image memory 35 m have a structure that can be easily inserted and removed individually from the rotating unit 23, as will be described in detail below. 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 m passes through the subject (not shown) placed on the bed 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 m. 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 miniaturization 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 over the entire inner circumference of the fixed portion of the surrounding gantry 5 (FIG. 6 and the like). In this case, a part of the detector peripheral circuit, an image memory, a host interface, etc. are arranged in a fixed portion in the gantry.

FIG. 1B is a circuit block diagram for explaining the inside of the rotating portion 23, particularly the detector 31 and its peripheral circuit 33. Peripheral circuits 33 in FIG. 1A include 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. Includes. 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. For the detector unit 30, in addition to the conventional TFT type detector, for example, a small photomultiplier type detector (for example, "micro PMT element" manufactured by Hamamatsu Photonics Co., Ltd.) and an avalanche effect (APD) were used. An amplification type detector, a photon counting type detector, or the like can be used. Further, a CMOS type or CCD type detector in which an analog-to-digital (AD) conversion circuit is turned on-chip can be used, and high-speed and low-noise readout can be realized. Alternatively, a CMOS type detector having high positioning accuracy of a plurality of detector arrays and easy weight reduction can be used (for example, Patent Document 7). 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, as will be described later, if it is not necessary to expand the X-ray irradiation area, the high voltage current required for the X-ray generating portion will not be increased. 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.

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. An 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 image memory 35 via the bus line 38 without parallel serial conversion, high-speed writing becomes possible. Although a magnetic recording medium can be used as the image memory 35, a semiconductor memory such as a DRAM or a NAND flash memory is suitable from the viewpoint of recording speed and reliability. On the other hand, when the image data is read from the image memory 35 after the end 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, it may be output as 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 5 rotations or more per second becomes easy. 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. ..

FIG. 1C is a block diagram for explaining the X-ray generating unit 25m inside the rotating unit 23 and the light source driving circuit 29. The X-ray generating portion 25m 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 m 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 m. The lithium-ion battery 27m 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. 2A shows a side view of the CT apparatus 100 according to the embodiment as viewed from the X-axis direction. The CT device 100 is composed of a sleeper 3-1 and a sleeper movement support portion (3-2) that supports and moves the sleeper 3-1 and a gantry 5 having an annular cavity portion. As described above, there is a rotatable rotating portion 23 inside the gantry 5, and the details thereof are as described in FIG. Further, the rotation center axis 1 is parallel to the Z axis, that is, the body axis direction. A fixing portion 24 is combined around the rotating portion 23 via a ball bearing or the like (not shown). The portion A surrounded by the broken line between the rotating portion 23 and the fixed portion 24 will be described below. 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.

FIG. 2B is a plan view of the CT device 100 as viewed from the Z-axis direction. Inside the annular portion of the gantry 5, a rotating portion 23 that rotates around the rotation center shaft 1 is attached via a bearing. Further, a timing belt 21 for rotating the rotating portion 23 and a rotating portion drive motor 19 are attached. As will be described later, 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. FIG. 2C is an enlarged view of the main part A in FIG. 2A, and a rotating part interface 6-1 made of a metal electrode is formed on the side surface part of the rotating part 23. Since the rotating unit interface 6-1 is located at a position facing the host interface composed of the convex connection terminal 4, the rotating unit interface 6-1 can be electrically connected by contacting each other when the rotating unit 23 is stationary. It should be noted that preferably, a position sensor or the like (not shown) using a Hall element or the like can be used in order to stop the convex connection terminal 4 and the rotating portion interface 6-1 at a position facing each other. Alternatively, if the rotating portion interface 6-1 is formed in a ring shape over the entire circumference of the annulus on the side surface of the rotating portion 23, electrical connection is possible regardless of the stationary position of the rotating portion 23.

3A and 3B are cross-sectional views taken from the X-axis direction for explaining the gantry portion of the CT apparatus 200 and 210 according to the embodiment. The X-ray generating unit 25m, which is a component incorporated inside the rotating unit 23, can be replaced according to the frequency of use due to deterioration of the target member, consumption of the electron beam generating cold cathode material, and carbon nanomaterial in this embodiment. is necessary. Similarly, the detector array 31m may also need to be replaced due to radiation damage to the semiconductor parts used or the humidity dependence of the X-ray scintillator material to be laminated. Therefore, in this embodiment, the X-ray generating portion 25 m and the detector array 31 m of the cartridge structure make it removable from the rotating portion 23. As shown in FIG. 3A, the rotating portion 23 is formed with a cartridge accommodating portion 25f and 31f (both broken lines) into which the X-ray generating portion 25m of the cartridge structure and the detector array 31m are inserted. The direction of insertion and removal of the X-ray generator 25 m and the detector array 31 m is the Z-axis, that is, the body axis direction, and the opening for inserting or removing the cartridge opens toward the Z-axis direction. For example, as will be described later, it is suitable for exchanging old and new cartridges with the cradle portion (FIG. 5A).

On the other hand, in the structure shown in FIG. 3B, the direction of insertion and removal of the X-ray generating portion 25 m and the detector array 31 m is perpendicular to the Z-axis direction, that is, the circular method drawn by the rotating portion 23. It is a linear direction. Further, as shown in the figure, the opening for inserting or removing the cartridge is opened from the inside of the rotating portion 23 with the central axis 1 toward the outer peripheral direction of the rotating portion 23. Therefore, there is an advantage that the fixed portion surrounding the rotating portion 23 does not interfere with the replacement work when the cartridge is replaced. Further, as in the structure already described with reference to FIG. 2, the structure is also suitable when the electrical connection terminals (4, 6-1) and the like are arranged on the side surface portion of the rotating portion. The cartridge structure is not limited to the X-ray generator 25 m and the detector array 31 m, and as described above or later, the secondary battery 27 or the image memory (FIG. 1 (a)) in order to cope with the increase in recording capacity. , FIGS. 5 (c), 5 (d), etc.) can also be a cartridge structure.

FIG. 3C is a plan view of the rotating portion 23 of the CT apparatus 200 according to the embodiment as viewed from the Z-axis direction. As will be described later, the regenerative brake circuit 50 may be built in the rotating portion 23. In this embodiment, in addition to the image memory 35 m and the secondary battery 27 m having a cartridge structure, the first X-ray generator 25 and the second X-ray generator 25-2, and the positions facing each other via the central axis 1. It has a first detector array 31 and a second detector array 31-2. The detector array 31 and the detector array 31-2 may be arranged at positions shifted in the Z-axis direction, that is, shifted. Further, the X-ray generating unit 25 and the X-ray generating unit 25-2 may be irradiated with X-rays at the same time or may be irradiated with a time lag. Further, different tube voltages (wavelengths) can be applied to the X-ray generating unit 25 and the X-ray generating unit 25-2 to perform multi-spectral analysis. Since the image memory and the secondary battery have a cartridge structure, it is possible to quickly respond to an increase in the amount of image data and consumption of the secondary battery. In this embodiment, the image memory 35 m and the secondary battery 27 m are made into cartridges, but as described above, the X-ray generators 25 and 25-2 or the detector array 31 may have a cartridge structure. In this way, by forming the main parts used inside the rotating portion 23 into a cartridge structure, not only the maintenance load such as replacement and repair is reduced, but also the continuous operation time of the device is extended or multi-spectral analysis is performed. It should also be noted that it brings about extremely useful actions and effects such as the versatility of imaging / inspection functions and the possibility of hybridization.

The CT apparatus 300 according to the embodiment will be described below with reference to FIG. FIG. 4A is a side view of the CT device 300 as viewed from the X-axis direction. The CT device 300 has a structure in which a gantry 7, support portions (9-1, 9-2) for supporting the gantry, and a gantry 5 movable in the Z-axis direction are mounted on the gantry support portions (9-1, 9-2). Inside the gantry 5, there is a rotatable rotating portion 23, and the rotation center axis 1 thereof is shown in the drawing. Inside the rotating portion 23, parts (not shown) having a cartridge structure already described with reference to FIG. 1 and the like are used. 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. A gantry moving carriage 11 incorporating a drive unit and wheels 15 for moving the gantry 5 in the Z-axis direction is attached to the lower part of the gantry 5. Further, as described in detail below, the electrical connection means for transmitting and receiving electric signals or electric power between the rotating portion 23 in the gantry and the gantry 7 is the upper portion (2-1) of the gantry and the rotating portion in the gantry. Hold on the side (not shown). A sleeper 3 is inserted in the hollow portion of the gantry 5 in the Z-axis direction in order to place a subject or other measurement object. During the imaging, only the gantry 5 moves in the Z-axis direction, and the subject is stationary on the bed 3 together with the sleeper 3, so that a robust and precise subject movement control means is not required. Therefore, the weight of the CT device 300 itself can be reduced. As will be described later, even if the scanning speed in the body axis (Z-axis) direction of the gantry is increased, it also has an effect of avoiding the physical and mental load and anxiety of the subject.

FIG. 4B is a plan view of the CT device 300 as viewed from the Y-axis direction. Two rails 13 for moving the gantry are provided on the upper part of the gantry 7 so that the gantry 5 moves on the gantry 7. If the gantry moving rail 13 and the wheels 15 are made of a conductive material such as metal, electric power is supplied to the drive motor 17 inside the gantry moving carriage 11, or a control signal or the like is transmitted to and from the gantry moving carriage 11. It becomes possible to give and receive. As described above, the host interface 2-1 which is an electrical connection means for exchanging electric signals or electric power between the rotating portion 23 and the gantry 7 in the gantry is attached to the upper part of the gantry, that is, the end point of the moving range of the gantry 5. It is placed in a certain predetermined position. In this embodiment, the sleeper 3 is attached to the upper parts of the gantry support portions 9-1 and 9-2, but it can be easily removed. Therefore, a subject holding means having another shape may be used instead of the sleeper 3. Further, since it is easy to remove the sleeper 3 and remove the gantry 3 from the gantry 7, it is convenient for maintenance and replacement of the gantry 5, and further different imaging characteristics, for example, light sources having different light source energies (wavelengths) can be used. It will be easy to replace it with the mounted gantry.

FIG. 4C is a plan view of the CT device 300 as viewed from the Z-axis direction. Inside the gantry 5, a rotating portion 23 that rotates around the rotation center shaft 1 is attached via a bearing (not shown) or the like. Further, a timing belt 21 for rotating the rotating portion 23 is attached to the gantry rotating portion drive motor 19 inside the gantry moving carriage 11. As will be described later, the regenerative brake circuit 50 may be built in the rotating portion 23. Further, since the rotating unit 23 has the rotating unit interface 2-2, it can be electrically connected at a position facing the host interface 2-1 when the rotating unit 23 is stationary. It should be noted that preferably, a position sensor or the like (not shown) using a Hall element or the like can be used in order to stop the host interface 2-1 and the rotating unit interface 2-2 at opposite positions. Further, a gantry moving carriage drive motor 17 for moving the gantry 5 in the Z-axis direction is provided inside the gantry moving carriage 11. The power supply for driving can be supplied from the gantry moving rail 13 as described above, but a secondary battery can also be built in the gantry moving carriage 11.

Further, as a moving means for moving the gantry 5 in the Z-axis direction, as will be described later (FIG. 5A, etc.), a structure may be towed from the gantry support portion 9-1 or 9-2 side. .. With this structure, since the rotating means of the rotating portion 23 in the gantry is arranged on the movable gantry moving carriage 11 or the like, it is not necessary to fix the gantry portion to the image pickup apparatus main body unlike the conventional case, and the gantry portion can be moved or removed. Etc. become easy. Since the structure of the rotating portion 23 has already been described in detail in other examples, it will be omitted. In this embodiment as well, the structure in which the detector array 31 is built in the rotating portion 23 has been described, but the detector array 31 is not inside the rotating portion 23, but is the inner circumference of the gantry 5 surrounding the rotating portion 23. The structure may be arranged over the entire circumference of the portion (FIG. 6 and the like).

FIG. 5A is a side view of the CT apparatus 400 according to the embodiment as viewed from the X-axis direction. The parts different from the examples already described will be described in detail below. As shown in FIG. 5A, the CT device 400 has a portion 9-3 that stands upright from the gantry 7 in the Y-axis direction, and this is called a cradle. Inside the rotating portion 23, parts (not shown) having a cartridge structure already described with reference to FIG. 1 and the like are used. The cradle 9-3 has a space (broken line portion 37) for the gantry 5 to stand by, the rotating portion interface 2-2 of the rotating portion 23 of the gantry 5 is composed of a non-contact interface structure 12, and the host interface 2-1 is provided. It is composed of a non-contact interface structure 10. These supply power in a non-contact manner while facing each other and in close proximity to each other, that is, charging the lithium ion battery inside the rotating unit 23, and exchanging data and signals between the rotating unit 23 and the host side. Illustrates a structure in which 12 on the rotating unit interface side and 10 on the host interface side are close to each other in the direction of the rotation center axis 1 and face each other. With this structure, the non-contact interface 12 can approach the non-contact interface 10 in the direction in which the gantry 5 moves in the Z-axis direction. There is a rotating portion 23 inside the gantry 5, and it rotates around the rotation central axis 1. The driving method thereof is the same as the structure described in FIG. 7 (c), that is, the rotating portion rotating motor 19 and the timing belt 21. It is a rotation by (not shown). As will be described later, the regenerative brake circuit 50 may be built in the rotating portion 23. Further, when power is not supplied from the gantry moving rail 13, a secondary battery (not shown) can be built in the gantry. On the other hand, an embodiment in which the gantry 5 is moved in the body axis (Z-axis) direction by the gantry support portion 9-1 or the cradle 9-3, the gantry towing motor 14 provided inside the gantry 7, and the gantry towing belt 8 is disclosed. doing.

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 inspection or calibration of the rotating portion 23 may be provided in the cradle. Further, for example, 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 is fitted with the supply port 16. A matching opening 18 is provided. 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. 5B 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 on the host interface side (10) is an AC / DC converter that converts commercial power to direct current, a high-frequency inverter that outputs high-frequency square waves, a waveform conversion circuit that converts this to sinusoidal waves, and safety. It is connected to the primary coil L1 via an isolation transformer or the like for securing. On the other hand, the secondary coil L2 is connected to a load such as a secondary battery via a rectifying smoothing circuit that returns high frequencies to direct current, a backflow diode, and the like. On the other hand, for transmission / reception of control signals or image data, for example, a wireless communication method (not shown) based on near-field magnetic field coupling is used. This is because the data transfer speed can be increased by about giga (G) bits / second. In addition, the above-mentioned wireless power supply and wireless communication may be performed by using the same coil or antenna.

5 (c) and 5 (d) are cross-sectional views for further explaining the structure of the gantry portion 5 and the cradle 9-4 according to the modified example of the above embodiment. That is, it discloses a structure capable of shortening the apparent charging time of the secondary battery in the gantry in a state where the gantry portion 5 is retracted to the cradle portion. As shown in FIG. 5 (c), the secondary battery is a cartridge-structured secondary battery 27 m as described above (FIG. 3 (a) and the like), and is inserted into the cartridge storage portion 27f. On the other hand, the gantry storage portion 37 of the cradle 9-4 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. 5D is a cross-sectional view when FIG. 5C is rotated by 90 degrees, and the secondary battery 27m is not inserted in the cartridge storage portion 27f inside the gantry portion 5, while the cradle A charged secondary battery 27 m is attached to the cartridge holder 22 inside the gantry storage portion 37 of 9-4. Therefore, when the gantry 5 is stored in the gantry storage unit 37, the charged secondary battery 27m can be inserted into the cartridge storage unit 27f for the secondary battery 27m in the gantry. In other words, by returning the used secondary battery 27m to the cradle 9-4 and at the same time supplying the charged secondary battery 27m to the gantry 5, the gantry section does not have to wait for the secondary battery 27m to be fully charged. 5 can start the next imaging operation. As a result, the apparent charging time of the secondary battery can be shortened, the time required for inspection can be shortened, and the operating efficiency of the device can be improved.

FIG. 6A is a plan view of the structure of the CT apparatus 500 according to the embodiment as viewed from the Z-axis direction, and FIG. 6B is a cross-sectional view of the gantry portion viewed from the X-axis or Y-axis direction. It is a figure. As shown in FIG. 6A, in this embodiment, an X-ray light source unit 25 m, a secondary battery 27 m, a high voltage control circuit 29 m, a regenerative brake circuit 50 described later, and the like are built in the rotating unit 23-2. On the other hand, a large number of detector units 30 mounted on the entire circumference are built in the annular fixed portion 24. The fixing portion 24 is fixed to the outer peripheral portion 5-2 of the gantry. Further, a motor 19 and a timing belt 21 for rotating the rotating portion 23-2 are shown. This structure is similar to the so-called Nutet-rotate CT device, but due to the high-speed rotation of the rotating unit 23-2, the number of units in the body (Z) axis direction of the detector 30 or the detector unit, or pixels. Since the demand for increasing the number is not strict, even if the fixed portion 24 is not retracted with respect to the X-ray beam when the rotating portion 23-2 is rotated, adverse effects such as artifacts in the reconstructed image are unlikely to occur. Since the X-ray light source unit 25 m, the secondary battery 27 m, the high voltage control circuit 29 m, the image memory 35 m, and the detector drive control circuit 41 m have a cartridge structure that can be easily attached and detached, the operating rate is improved and the imaging time is extended. The maintenance load can be reduced.

This will be described in more detail with reference to FIG. 6 (b). A fixing portion 24 and a rotating portion 23-2 are incorporated in the gantry 5-2. As shown in the figure, the arrangement of the X-ray generating unit 25m mounted inside the rotating unit 23-2 is offset to the right with respect to the Z axis with respect to the detector unit 30. Further, the X-ray emission direction is not perpendicular to the Z axis, but is angled so as to be inclined in the Z axis direction so as to irradiate the detector unit 30 at a position opposite to the Z axis. Conventionally, when the number of detector units 30 in the Z-axis (body axis) direction increases, the difference in the incident angle of X-rays increases depending on the position of the detector units 30 in the Z-axis direction in the Z-axis direction. However, in the present invention, since it is easy to increase the rotation speed of the rotating portion 23-2 and increase the moving speed of the gantry in the Z-axis direction, the width of the detector unit 30 in the Z-axis (body axis) direction or It has become easier to reduce the number.

FIG. 6C is a cross-sectional view for explaining the internal structure of the CT apparatus 510 according to the modified example of the above embodiment, particularly the gantry 5-2. A fixing portion 24 and a rotating portion 23-2 are incorporated in the gantry 5-2. The difference from the structure shown in FIG. 6 (b) is that the diameter of the rotating portion 23-2 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. The X-rays emitted from the device reach the detector 30 without being hindered by the fixed portion 24. This structure is similar to the so-called stationary rotation type CT device, but when a large current is passed from the brush to the slip ring while sliding it at high speed, the contact surface generates heat and causes seizure. Not only that, the detector 30 performs erroneous photoelectric conversion due to a light emission phenomenon due to sparks or the like, so the structure is not particularly suitable for high-speed scanning (imaging). In this structure, the rotating portion 23-2 of the portion facing the central axis of rotation of the X-ray light source 25 m on the optical path of the X-ray emitted from the X-ray light source 25 m may have some influence. is there.

A structure that solves this problem will be described below with reference to FIG. FIG. 7A is a plan view of the CT apparatus 600 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 23-2. A detector (not shown) is arranged on the inner circumference of the fixed portion 24 over the entire circumference. The rotating unit 23-2 contains 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 23-2 to reduce the influence on the intensity and the traveling direction of the X-ray beam 26. The opening 28 does not necessarily have to be in a state where all the members have been removed (air only), and for example, a protective cover made of resin having high X-ray transmittance may be left. FIG. 5B is a cross-sectional view of the structure inside the gantry when the opening 28 is 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 beam that has passed through the opening 28 reaches the detector 30. A fiber optic plate that shields X-rays, an X-ray scintillator, or the like may be laminated above the detector 30.

FIG. 7 (c) is an enlarged view seen from the Z-axis direction for explaining the structure of the broken line portion B in FIG. 7 (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. FIG. 7D is a plan view of the same portion when the opening 28 is viewed from the X-ray generating portion 25 m. Irradiated X-rays because the light receiving surfaces of the plurality of detectors 30 attached to the fixed portions 24 or the pixel arrays are directly exposed to the X-ray light source 25 m by the openings 28 formed in the rotating portion 23-2. It enables exposure with reduced attenuation.

FIG. 8A is a flowchart for explaining a driving method of the CT apparatus according to the present embodiment. As shown in the figure, after the movement of the sleeper or the gantry and the start of rotation of the rotating portion, imaging by X-ray irradiation is started. In this case, a method of starting the rotation of the rotating portion after moving the gantry to a predetermined position or the sleeper, and a method of starting the rotation of the rotating portion and starting the movement of the sleeper or the gantry after reaching the predetermined rotation speed. There is a way. Further, as shown by the broken arrow, after the imaging by moving the gantry or the sleeper in the Z-axis (positive) direction is completed, the moving direction of the gantry or the sleeper is reversed and the image is taken by moving in the Z-axis (negative) direction. An imaging method can be considered. Further, there are a method of reversing the rotation direction of the rotating portion and a method of not changing the rotation direction of the rotating portion (normal rotation) when the direction of movement of the sleeper or the gantry is reversed.

FIG. 8B is a perspective view for explaining the spiral movement locus of the X-ray beam accompanying the movement of the sleeper or gantry in the Z-axis direction and the rotation of the rotating portion. 8 (c) and 8 (d) are loci obtained by adding the rotation direction of the rotation of the rotating portion to this. However, for the sake of simplification of the drawing, it is not a three-dimensional perspective view but a two-dimensional schematic view. The broken lines are the loci when the moving direction of the gantry is reversed. In the case of FIG. 8C, since the rotation of the rotating portion is also reversed, the loci complement each other. On the other hand, in the case of FIG. 8D, since the rotation directions of the rotating portions 23 are not reversed, their trajectories intersect with each other. Which is preferable can be selected depending on the image reconstruction algorithm or the appearance situation of so-called artifacts. As described above, the digital data obtained from the detector array 31 is recorded in the image memory 35 in real time. As shown in FIG. 1 (b), the digital data can be recorded in the image memory as it is in the image memory 35 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 2-2 via the host interface 2-1 and the image is displayed in the operation / control unit (not shown). After the reconfiguration process of, it is displayed on the monitor. Further, the lithium ion battery 27 is charged in parallel, and a series of drive sequences are completed to enter the standby state.

The rotating portion of the CT apparatus 700 according to the embodiment, particularly inside the gantry, will be described with reference to FIG. 9 (a) is a plan view of the rotating portion 23 inside the gantry 5 as viewed from the Z-axis direction, and FIGS. 9 (b) and 9 (c) explain the structure of the broken line portion 39 in (a). It is a partially enlarged view for doing. The rotating unit 23 includes a detector peripheral circuit including an X-ray generator 25, a secondary battery 27, a light source drive circuit 29, a detector array 31, a signal amplification / analog-to-digital (AD) conversion circuit, a signal scanning / control circuit, and the like. 33, a detector drive control circuit 41, a non-contact interface 2-2, a digital signal processing circuit (not shown), a parallel serial conversion circuit, and the like are built-in. As will be described below, the regenerative brake circuit 50 is built in the rotating portion 23 or the fixed portion in the gantry, and the electromagnetic induction coil is provided around either the rotating portion 23 or the fixed portion. The regenerative braking circuit 50 recovers the electromotive force induced in the electromagnetic induction coil.

In the structure (39-1) of FIG. 9B, for example, the north and south poles of the permanent magnets (34-1) are alternately arranged in a ring shape on the fixed portion side. On the other hand, on the rotating portion side, the induction coil (36-1) is wound around the iron core (32-1), and therefore, the regenerative braking circuit 50 is provided inside the rotating portion. On the other hand, in the structure (39-2) of FIG. 9C, for example, the north and south poles of the permanent magnets (34-2) are alternately arranged in a ring shape on the rotating portion side. On the other hand, on the fixed portion side, since the induction coil (36-2) is wound around the iron core (32-2), the regenerative brake circuit 50 may be provided inside the fixed portion. If electric energy is stored in a secondary battery or an electric double layer capacitor described later inside the rotating portion 23, the structure shown in FIG. 9B is preferable. In the structure of the structure of FIG. 9B, an electromotive force is generated in the induction coil (36-1) even when the rotating portion 23 is forcibly rotated by an external motor via a timing belt described later. It is possible to charge the secondary battery 27, and the rotational energy generated in the induction coil (36-1) is recovered in the secondary battery or an electric double layer capacitor described later until the rotation stops even after the above-mentioned forced rotation ends. Because it can be done.

As the permanent magnet, for example, a neodymium magnet can be used. As will be described later, once the imaging operation is completed, the rotational movement of the rotating part inside the gantry is unnecessary, but if the moment of inertia of the rotating gantry can be converted into electrical energy without mechanically stopping it, Energy saving effect can be obtained. In this embodiment, the regenerative brake circuit 50 plays the role. In the CT apparatus, rotation (imaging mode) and stop (standby mode) are frequently repeated, so that the effect of recovering the rotational energy of the rotating part is remarkable, especially when the rotation speed of the rotating part is increased to perform high-speed scanning. Is even more effective.

The regenerative brake 50 in this embodiment will be described below with reference to FIG. 9 (d). The CT apparatus according to the present invention starts the imaging operation after the rotation of the rotating unit 23 starts, and after the imaging is completed, the rotation of the rotating unit 23 slows down and the rotational movement stops. As described above, since the rotation start and rotation stop are repeated within a short time in one imaging operation, effectively utilizing the rotational kinetic energy of the rotating portion 23 reduces the consumption of the secondary battery and saves energy. Also contributes. FIG. 1D is a circuit configuration diagram for explaining the regenerative brake 50 provided inside the rotating portion 23. One end of the bidirectional DC-DC converter 42 is connected to the secondary battery 27. Further, it is connected to the induction coil 36 via a DC-AC converter. On the other hand, the induction coil 36 is connected to a capacitor, preferably an electric double layer capacitor 44, via an AC-DC converter, and further connected to a bidirectional DC-DC converter 42. The rotational kinetic energy of the rotating portion 23 is converted into the counter electromotive force generated in the induction coil 36, and the electric double layer capacitor 44 is charged. The secondary battery 27 can also be charged via the bidirectional DC-DC converter 42.

Generally, the energy recovery efficiency of the capacitor is 90% or more, which is higher than the energy recovery efficiency of about 60% when charging the secondary battery. In particular, it is suitable when the rotating portion 23 decelerates (recovers) and immediately rotates (discharges) the rotating portion 23 as in the present embodiment. The bidirectional DC-DC converter 42 may use a circuit method that combines a step-down chopper circuit and a step-up chopper circuit, or a PWM (Pulse Width Modulation) method that uses a DSP (Digital Signal Processor) and an AD converter. it can. In the case of this configuration, when the secondary battery 27 inside the rotating unit 23 is used as a power source to generate an AC voltage and applied to the electromagnetic induction coil 36-1 to rotate the rotating unit 23, the rotating unit 23 is used as a rotor. It can also be used as a direct drive (DD) motor in which the fixed portion side of the gantry 5 is a stator.

FIG. 10A is a plan view of a rotating portion of the image pickup apparatus 800 according to the embodiment, particularly in the gantry, as viewed from the Z-axis direction, and FIG. 10B describes the structure of the broken line portion 39R in FIG. It is a partially enlarged view for. In this embodiment, the rotating portion 23 is composed of two parts (23-1 and 23-2), one rotating portion (23-1 in this figure) is equipped with a timing belt 21, and the other (main). In the figure, 23-2) has a ratchet structure that is mechanically interlocked with the rotating portion (23-1). That is, as shown in FIG. 10B, a claw 40 is attached around the rotating portion 23-1, and when the rotating portion 23-1 rotates clockwise, it fills a groove on the inner circumference of the rotating portion 23-2. It can be caught and transmit torque. On the other hand, when the rotating portion 23-1 is stopped or rotated counterclockwise, the claw 40 slips over the groove on the inner circumference of the rotating portion 23-2 without being able to transmit torque. In addition to the claw seat ratchet structure shown here, an optimum structure such as a ball ratchet structure can be appropriately selected.

FIG. 10C is a flowchart for explaining a driving method when the regenerative brake is used in the embodiment (for example, CT device 700). As shown in the figure, after the rotation of the rotating portion 23 starts, the sleeper or the gantry starts to move. Next, imaging by X-ray irradiation is started. The digital data obtained from the detector array is recorded in the image memory in real time. As described above, the digital data can be recorded in the image memory as the parallel data without the need for parallel serial conversion. After the imaging is completed, the rotational kinetic energy of the rotating portion 23 generates a counter electromotive force in the induction coil and recovers it as electrical energy, and the rotational movement is decelerated while charging the capacitor or the secondary battery. Finally, the gantry stops at a predetermined position, the data recorded in the image memory is read from the rotating unit interface via the host interface, and after the image reconstruction process is performed by the operation / control unit (not shown), it is displayed on the monitor. Shooting information is displayed. In addition, the secondary battery is charged in parallel, and a series of sequences are completed to enter the standby state. Although not shown, as will be described later, when the above gantry stops at a predetermined position and returns to the start of imaging (the first step in the flowchart), the used secondary battery is disconnected and already charged. It is also possible to add a step to install a finished secondary battery.

FIG. 10D is a flowchart for explaining a driving method in the case of the CT apparatus (800) using the ratchet structure shown in FIGS. 10A and 10B. As shown in the figure, the rotating unit 23-1 starts rotating in the direction in which torque is applied to the rotating unit 23-2, and then or at the same time, the bed or gantry starts moving. Next, imaging by X-ray irradiation is started. The digital data obtained from the detector array is recorded in the image memory in real time. As will be described later, the digital data can be recorded in the image memory as it is without the need for parallel serial conversion. When the rotational torque of the rotating portion 23-1 is reduced or stopped after the imaging is completed, the rotating portion 23-2 is released from the coupling with the rotating portion 23-1 and idles. Since there is a regenerative brake 50 (not shown) inside the rotating portion 23-2, as described above, the rotational kinetic energy generates a countercurrent force in the induction coil and recovers it as electric energy, and the capacitor or the second The rotational movement of the rotating unit 23-2 slows down while charging the next battery. Finally, the gantry stops at a predetermined position, the data recorded in the image memory is read from the rotating unit interface via the host interface, and after the image reconstruction process is performed by the operation / control unit (not shown), it is displayed on the monitor. Shooting information is displayed. In addition, the secondary battery is charged in parallel, and a series of sequences are completed to enter the standby state. Although not shown, as described above, when the above gantry stops at a predetermined position and returns to the start of imaging (the first step in the flowchart), the used secondary battery is already disconnected. You can also add a step to install a charged rechargeable battery.

FIG. 11A is a side view of the image pickup apparatus 900 according to another embodiment as viewed from the X-axis direction. In this embodiment, two gantry units (gantry 5 and gantry 5-2) are mounted on a gantry 7. Furthermore, it also has two cradle parts (9-3 and 9-4), and in particular, the cradle 9-4 has a donut-shaped hollow structure so that the subject and the sleeper (not shown) can pass through. .. Different inspections such as a combination of multiple gantry units, for example, a combination of an X-ray CT examination gantry and a PET (positron emission tomography) examination gantry, or a combination of an X-ray CT examination gantry and a near-infrared diffuse imaging gantry. This can be achieved with a single imaging device. Further, a protective cover 51 for preventing the subject or the object to be measured from coming into contact with the gantry during the movement of the gantry is provided on the gantry along the moving direction of the gantry. Further, the plurality of gantry units can be driven individually or in conjunction with each other. More preferably, the wireless communication interface is combined with the gantry section or the rotating section so that a signal output from the rotating section or the gantry section while the gantry section is moving in the body axis direction, for example, a fluoroscopic image of the subject can be monitored. The structure may be provided between the operation / control unit.

FIG. 11B is a perspective view of the CT apparatus 1000 according to another embodiment, and FIG. 11C is an X in the peripheral portion of the rotating portion 23-3 inside the gantry portion 5 and the fixing portion 24-2. It is sectional drawing seen from the axis or the Y-axis direction. In the CT device 1000, the Z-axis direction is perpendicular to the horizon, that is, coincides with the direction of gravity. Therefore, the moving direction of the gantry 5 is the vertical direction as shown by the broken line arrow. A motor or the like for raising or lowering the gantry 5 is built in the cradle 9-5. Two columns 7-1 and 7-2 corresponding to a gantry for holding the cradle 9-5 and the gantry 5 are provided on the bottom support or the upper part of the bottom cradle 9-6. Due to the miniaturization and weight reduction of the gantry portion according to the present invention described above, a CT device that adopts such a gantry movement direction becomes possible.

As shown in FIG. 11C, the rotating portion 23-3 and the fixing portion 24-2 according to the present invention are combined in the vertical direction via a plurality of ball bearings 53 arranged in an annular shape. As already described (FIGS. 1 (a), 3 (c), etc.), the regenerative brake circuit 50 (not shown) may be built in the rotating portion 23-3. The rotating portion 23-3 can be rotated by an external motor (not shown) via the timing belt 21. Further, the permanent magnets 34-3 and 34-4 are paired with each other so that the rotating portion 23-3 and the fixed portion 24-2 face each other and have the same polarity (that is, the N poles or S. They are arranged so that the poles face each other). Each of the permanent magnets 34-3 and 34-4 may be a single donut-shaped permanent magnet, or may have a structure in which a plurality of magnets are arranged on the circumference. By arranging the permanent magnets in the rotating portion 23-3 and the fixed portion 24-2 in this way, magnetic forces repelling each other are generated, and the load applied to the ball bearing 53 by the weight of the rotating portion 23-3 can be reduced. it can. It is a magnetic levitation method, and it is possible to reduce the starting torque when rotating the rotating portion 23-3, or reduce the wear of ball bearings and the generation of noise due to high-speed rotation. The narrower the gap d between the rotating portion 23-3 and the fixed portion 24-2, the greater the repulsive force. However, in consideration of the surface processing accuracy of both, for example, about 0.5 to 7 mm (mm). Set to range.

FIG. 12A is a side view of the medical examination vehicle 1100 according to the embodiment. In this embodiment, the front-rear direction of the vehicle is defined as the X-axis, the height direction of the vehicle, that is, the vertical direction is defined as the Y-axis, and the lateral direction of the vehicle, that is, the direction orthogonal to the X-axis and the Y-axis is defined as the Z-axis. This is because the body axis direction of the CT device (for example, CT device 600 or the like) according to the present invention coincides with the Z-axis direction of the vehicle. On the side surface of the vehicle, there is a subject insertion portion 54 into which a sleeper 3 on which a subject such as a human body is placed is inserted. Imaging can be performed while moving a gantry or a sleeper 3 (not shown). FIG. 12B is a side view of the medical examination vehicle 1200 according to another embodiment. In this embodiment, the front-rear direction of the vehicle is defined as the X-axis, the height direction of the vehicle, that is, the vertical direction is defined as the Z-axis, and the lateral direction of the vehicle, that is, the direction orthogonal to the X-axis and the Z-axis is defined as the Y-axis. This is because the body axis direction of the gantry vertical movement type CT device 57 (for example, CT device 1000 or the like) coincides with the Z axis of the vehicle. In both cases (a) and (b), a solar panel 58, stairs or step 59s are provided.

12 (c) and 12 (d) show a plan view of the medical examination vehicle 1110 and the medical examination vehicle 1120 according to the modified example of the medical examination vehicle 1100 when viewed from above. In the case of the medical examination vehicle 1110, the opening corresponding to the subject insertion portion 54 is provided only on one side surface of the vehicle, and therefore, the CT device 55 to be mounted is a sleeper moving CT device (for example, CT device 500). Can be used. For example, the sleeper 3-1 can easily move to the inside of the CT device 55 or get out of the CT device 55 with the subject placed on the bed. This is because it is difficult for the subject to move in and out of the opening by itself.

On the other hand, in the medical examination vehicle 1120 shown in FIG. 12D, openings corresponding to the subject insertion portion 54 are provided on both side surfaces of the vehicle, and therefore, the CT device 56 to be mounted is the sleeper movable type. A CT device may be used, but a gantry mobile CT device 56 (for example, a CT device 600 or the like) can be used. Since the subject moves by itself and enters the opening and can exit from the opening on the opposite side after the examination (imaging) is completed, it is efficient when continuously inspecting (imaging) the subject in the case of mass examination or the like. Is. Therefore, it is easy to continuously insert a plurality of inspection objects in the same direction, including objects other than the human body, and sequentially send them out to the opposite side of the vehicle. In the embodiment of FIG. 12C, a sleeper moving device (3-1, 3-2) was further required outside the vehicle, but in this embodiment, for example, a simple moving sleeper 61 called a stretcher. It suffices to bring it closer to the opening, and it is not always necessary to load a sleeper moving device or the like. In the past, it was difficult to mount a CT device on a medical examination vehicle because a space was required to move the sleeper, but this embodiment enables the development of advanced medical activities even in remote areas. Became. In FIGS. 12 (c) and 12 (d), reference numerals 63-1 to 63-6 are data processing, power control room, other testing equipment room, biochemical testing room, examination room, waiting room or changing room. And so on.

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 a gantry for PET or a gantry using near infrared light as a light source. Multi-image diagnosis for light source energy is realized. In addition, the spread of high-performance medical examination vehicles equipped with inspection equipment such as CT is expected to develop advanced medical activities on a global scale.

1: Rotation center axis, 2-1: Host interface, 2-2: Rotating part interface, 3: Sleeper, 4: Convex connection terminal, 5: Gantry, 6: Concave connection terminal, 7: Stand, 8: Gantry towing Belt, 9-1, 9-2: Stand support, 9-3: Cradle, 10: Non-contact host interface 11: Gantry moving carriage, 12: Non-contact rotating part interface, 13: Gantry moving rail, 14: Gantry Towing motor, 15: Wheels at the bottom of the gantry, 16: Supply port, 17: Gantry moving carriage drive motor, 18: Opening, 19: Rotating part drive motor, 20: Sample holding part, 21: Rotating part rotating belt, 22 : Cartridge holder, 23: Rotating part, 24: Fixed part, 25, 25-2: X-ray generating part, 25C: Carbon nanomaterial electron beam generating cold cathode, 25A: Anodic target, 26: X-ray beam, 27: 2 Next battery, 28: Opening of rotating part, 29: Light source drive circuit, 29-1: Voltage booster circuit, 29-2: High voltage control circuit, 30: Detector unit, 31, 31-2: Detector array, 32-1, 32-2: Iron core, 33: Detector peripheral circuit, 34-1, 34-2, 34-3, 34-4: Permanent magnet, 35: Image memory, 36: Induction coil, 37: Gantry Storage part, 38: Bus line, 39: Outer circumference of rotating part 5 and part of outer circumference of gantry part 23, 39R: Ratchet structure, 40: Claw part of ratchet mechanism, 41: Detector drive control circuit, 42: Bidirectional DC -DC converter, 43: signal amplification / AD conversion circuit, 44: electric double layer capacitor, 45: signal scanning / control circuit, 47: digital signal processing circuit, 49: parallel serial conversion circuit, 50: regenerative braking circuit, 51: Subject protection member, 53: ball bearing, 54: subject insertion part on the side surface of the vehicle body, 55: sleeper movable CT device mounted on the vehicle, 56: gantry horizontal moving CT device mounted on the vehicle, 57: vehicle Gantry vertical movement type CT device mounted on, 58: Solar panel, 59: Stairs or steps, 61: Stretcher, 63-1, 2, 3, 4, 5, 6: Other space for examination

Claims (5)

A CT device having a rotating part that rotates about the body axis direction inside the gantry, and any of the light source, detector, image memory, or secondary battery built in the rotating part has a cartridge structure. In addition, with respect to the cartridge storage portion for individually storing the light source, the detector, the image memory, or the secondary battery having the cartridge structure, from the inside of the rotating portion with the central axis to the normal direction of the outer circumference of the rotating portion. A CT device having a light source having a cartridge structure, a detector, an image memory, or an individual opening for inserting and removing a secondary battery on the inner peripheral surface of the gantry parallel to the central axis. A gantry with a built-in rotating part that rotates about the body axis direction, a gantry on which the gantry is placed, a drive unit that moves the gantry in the direction of the central axis at the upper part of the gantry, and a cradle that makes the gantry stand by. A CT device having an upright structure on the upper part of a gantry, wherein any of a light source, a detector, an image memory, or a secondary battery built in the rotating portion has a cartridge structure, and a light source having the cartridge structure. A light source, a detector, an image memory, or a secondary battery having the cartridge structure is inserted in the direction of the central axis of the rotating portion into the cartridge storage portion for individually storing the detector, the image memory, or the secondary battery. And a cartridge holder having a separate opening for removal on the side surface of the gantry perpendicular to the central axis and further holding a light source, a detector, an image memory, or a secondary battery having the cartridge structure. CT device in the cradle. The CT apparatus according to claim 1 or 2, 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 or 2, wherein the detector is either a photomultiplier tube type detector, an avalanche diode type detector, or a photon counting type detector. After the gantry is retracted to the cradle, the secondary battery having a cartridge structure inside the rotating portion is removed in the direction of the central axis, and the secondary battery having a cartridge structure charged in the cartridge storage portion after being removed. The method for driving a CT device according to claim 2, wherein the CT device is inserted.