JP2022163405A - Magnetic resonance imaging apparatus - Google Patents

Abstract

To prevent dew condensation water generated in the periphery of a freezing machine from having an impact on a peripheral device.SOLUTION: A magnetic resonance imaging apparatus includes: a superconducting magnet for generating a static magnetic field; a freezing machine for cooling the superconducting magnet; a gradient magnetic field coil for generating a gradient magnetic field; cooling means for circulating cooling water for cooling the gradient magnetic field coil; and a dew condensation water supply part. The dew condensation water supply part reserves dew condensation water generated in the freezing machine and supplies the reserved dew condensation water to the cooling means.SELECTED DRAWING: Figure 1

Description

The embodiments disclosed in the specification and drawings relate to a magnetic resonance imaging apparatus.

2. Description of the Related Art A magnetic resonance imaging device (hereinafter referred to as an MRI device) is a device that takes an image of the inside of a subject using the magnetic resonance phenomenon. Such an MRI apparatus includes a static magnetic field magnet that generates a static magnetic field in an imaging region, a gradient magnetic field coil that applies a gradient magnetic field to a subject placed in the static magnetic field, and a high frequency coil that applies a high frequency pulse to the subject. , equipped with various equipment necessary for imaging the inside of the subject. Some of these devices generate heat during operation and require cooling. Therefore, each device to be cooled is cooled by circulating a coolant such as cooling water through each device that requires cooling.

Equipment that requires cooling includes equipment that requires constant cooling and equipment that requires cooling only while the MRI apparatus is in operation. Equipment that requires constant cooling is, for example, equipment that continues to operate even when the MRI apparatus is not in operation. Equipment that requires constant cooling is, for example, a refrigerator for cooling a coolant for a superconducting magnet used as a static magnetic field magnet. Equipment that requires cooling only while the MRI apparatus is in operation is, for example, equipment whose operation is stopped while the MRI apparatus is not in operation. Equipment that requires cooling only while the MRI apparatus is in operation is, for example, a gradient magnetic field coil, a gradient magnetic field power supply, and the like.

A static magnetic field magnet, which requires constant cooling, is generally installed in an imaging room where the temperature and humidity are moderately controlled. For example, if the area where the MRI apparatus is installed has a hot and humid climate, the humidity in the imaging room often becomes higher than the control set value. At that time, condensation occurs around the refrigerator that cools the static magnetic field magnet. Once dew condensation occurs, it is difficult to remove. For this reason, dew condensation generated around the refrigerator may reach the peripheral equipment along the substantially circular outer peripheral shape of the static magnetic field magnet, thereby inducing failure of the peripheral equipment.

JP 2014-135991 A

One of the problems to be solved by the embodiments disclosed in this specification and drawings is to prevent the condensed water generated around the refrigerator from affecting peripheral devices. However, the problems to be solved by the embodiments disclosed in this specification and drawings are not limited to the above problems. A problem corresponding to each effect of each configuration shown in the embodiments described later can be positioned as another problem.

A magnetic resonance imaging apparatus according to an embodiment includes a superconducting magnet that generates a static magnetic field, a refrigerator that cools the superconducting magnet, a gradient magnetic field coil that generates a gradient magnetic field, and cooling that circulates cooling water that cools the gradient magnetic field coil. means and a condensed water supply. The condensed water supply unit stores condensed water generated in the refrigerator and supplies the stored condensed water to the cooling means.

FIG. 1 is a block diagram showing an example of the functional configuration of the magnetic resonance imaging system according to the first embodiment. FIG. 2 is a schematic diagram showing an example of the configuration of the magnetic resonance imaging apparatus according to the first embodiment. FIG. 3 is a diagram illustrating an example of a configuration of a control unit of a reuse water supply unit according to the first embodiment; FIG. 4 is a flowchart exemplifying a processing procedure of reusable water supply processing by the magnetic resonance imaging apparatus according to the first embodiment. FIG. 5 is a flowchart exemplifying a processing procedure of reusable water supply processing by the magnetic resonance imaging apparatus according to the second embodiment. FIG. 6 is a flowchart exemplifying a processing procedure of reusable water supply processing by the magnetic resonance imaging apparatus according to the third embodiment. FIG. 7 is a flow chart illustrating the operation of the magnetic resonance imaging apparatus according to the fourth embodiment.

Hereinafter, embodiments of the magnetic resonance imaging apparatus will be described in detail with reference to the drawings. In the following description, components having substantially the same functions and configurations are denoted by the same reference numerals, and overlapping descriptions will be given only when necessary.

(First embodiment)
FIG. 1 is a block diagram showing an example of a functional configuration of a magnetic resonance imaging system (hereinafter referred to as an MRI system) 200 including a magnetic resonance imaging apparatus (hereinafter referred to as an MRI (Magnetic Resonance Imaging) apparatus) 100 of the present embodiment. is. The MRI system 200 has an MRI apparatus 100 and a cooling water supply device 101 . The MRI apparatus 100 includes a static magnetic field magnet 1, a gradient magnetic field coil 2, a high frequency coil 3, a top plate 4, a gradient magnetic field power supply 5, a transmitter 6, a receiver 7, a sequence controller 8, a computer system 9, a compressor 10, a refrigerator. 11 , a cooling water distribution unit 12 , a cooling water branching unit 14 , a reuse water supply unit 15 , and a cooling water supply device 101 . For example, the static magnetic field magnet 1, the gradient magnetic field coil 2, the high frequency coil 3, the top plate 4, the refrigerator 11, the cooling water branch section 14, and the reuse water supply section 15 are installed inside an imaging room where MRI imaging is performed. . Further, for example, the gradient magnetic field power supply 5, the transmitter 6, the receiver 7, the sequence controller 8, the computer system 9, the compressor 10, and the cooling water distributor 12 are installed inside a computer room different from the imaging room. . Further, for example, the cooling water supply device 101 is installed outdoors.

The static magnetic field magnet 1 is a superconducting magnet that generates a static magnetic field in an imaging region where the subject P is placed. For example, the static magnetic field magnet 1 has a vacuum container 1a, a refrigerant container 1b and a superconducting coil 1c. The vacuum container 1a is formed in a substantially cylindrical shape. The inside of the cylindrical wall of the vacuum container 1a is maintained in a vacuum state. A space formed inside the vacuum vessel 1a serves as an imaging region in which the subject P is placed. The refrigerant container 1b is formed in a substantially cylindrical shape and accommodated within the cylindrical wall of the vacuum container 1a. The cylindrical wall of the refrigerant container 1b accommodates a refrigerant for keeping the inside of the container at a sufficiently low temperature. Liquid helium, for example, is used as the coolant. The superconducting coil 1c is arranged inside the cylindrical wall of the coolant container 1b. The superconducting coil 1c is immersed in a coolant such as liquid helium. The superconducting coil 1c generates a static magnetic field in the imaging area inside the vacuum vessel 1a.

It is arranged inside the static magnetic field magnet 1 . The gradient magnetic field coil 2 is formed in a substantially cylindrical shape. The gradient magnetic field coils 2 generate gradient magnetic fields in the X-axis, Y-axis, and Z-axis directions set in the imaging region by current supplied from the gradient magnetic field power source 5 . Since a pulse current is repeatedly supplied to the gradient magnetic field coil 2 during execution of the scan, the gradient magnetic field coil 2 generates heat.

A high-frequency coil 3 is arranged inside the gradient magnetic field coil 2 . The high-frequency coil 3 irradiates the subject P placed in the imaging region with high-frequency pulses transmitted from the transmitter 6 . The radio frequency coil 3 also receives magnetic resonance signals emitted from the subject P due to excitation of hydrogen nuclei by radio frequency pulses.

The top plate 4 is installed inside the gradient magnetic field coil 2 . The top plate 4 is supported by a bed (not shown). A subject P is placed on the tabletop 4 at the time of imaging. The tabletop 4 is moved together with the subject P into the imaging area. The tabletop 4 can be moved inside and outside the imaging region with the subject P placed thereon.

The gradient magnetic field power supply 5 supplies current to the gradient magnetic field coil 2 based on instructions from the sequence control device 8 . The gradient magnetic field power supply 5 generates heat during execution of scanning.

The transmission unit 6 transmits high frequency pulses to the high frequency coil 3 based on instructions from the sequence control device 8 . The transmitter 6 has a high frequency power source for generating high frequency pulses to be transmitted to the high frequency coil 3 . The high frequency power supply generates heat during scanning.

The receiver 7 detects magnetic resonance signals received by the high-frequency coil 3 and digitizes the detected magnetic resonance signals to generate raw data. The receiving unit 7 then transmits the generated raw data to the sequence control device 8 .

The sequence controller 8 scans the subject P by driving the gradient magnetic field power supply 5, the transmitter 6, and the receiver 7 under the control of the computer system 9, respectively. Then, the sequence control device 8 receives the raw data transmitted from the receiving section 7 as a result of scanning, and transmits the raw data to the computer system 9 .

The computer system 9 controls the entire MRI apparatus 100 based on operations performed by the operator. For example, the computer system 9 has a processing circuit, storage section, input section, display section, communication section, and the like.

The processing circuit has a processor such as a CPU as a hardware resource. The processing circuitry functions as the core of the MRI apparatus 100 . For example, the processing circuit has a sequence control function, an image reconstruction function, and a display control function by executing various programs. In the sequence control function, the processing circuit causes the sequence control device 8 to execute scanning based on the imaging conditions input by the operator. In the image reconstruction function, the processing circuit reconstructs the image of the subject P based on the raw data transmitted from the sequence control device 8 . In the display control function, the processing circuit causes the display unit to display various information.

Although the sequence control function, the image reconstruction function, and the display control function are realized by a single processing circuit, the processing circuit is configured by combining a plurality of independent processors, and each processor executes a program. Each function may be realized by executing it. Also, the control function, the image reconstruction function, and the display control function may be implemented as individual hardware circuits. The above description of each function executed by the processing circuit is the same for each of the following embodiments and modifications.

The term "processor" used in the above description includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or an ASIC, a programmable logic device (e.g., Simple Programmable Logic Device (SPLD) , Complex Programmable Logic Device (CPLD), Field Programmable Gate Array (FPGA), etc. The processor functions by reading and executing a program stored in memory 152. In addition, instead of storing the program in the memory 152, the program may be directly embedded in the circuit of the processor.In this case, the processor can read and execute the program embedded in the circuit. Note that each processor of this embodiment is not limited to being configured as a single circuit for each processor, but is configured as a single processor by combining a plurality of independent circuits, and its function is implemented by Furthermore, a plurality of components in Fig. 1 may be integrated into a single processor to realize its functions. The same applies to modified examples.

The storage unit is a memory that stores reconstructed images and the like. The storage unit is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. Also, the storage unit may be a driving device or the like that reads and writes various information from/to a portable storage medium such as a CD-ROM drive, DVD drive, or flash memory. For example, the storage unit stores k-space data, MR image data, control programs, and the like.

The display unit displays various information including an image of the subject. For example, the display unit displays the generated MR image, an imaging protocol setting screen, and the like. As the display unit, for example, a CRT display, a liquid crystal display, an organic EL display, an LED display, a plasma display, or any other display known in the art can be used as appropriate.

The input unit is an interface that receives various inputs from the operator. The input unit includes an input device that receives various commands from the user. A keyboard, a mouse, various switches, a touch screen, a touch pad, etc. can be used as input devices. Input devices are not limited to those having physical operation parts such as mice and keyboards. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the MRI apparatus 100 and outputs the received electrical signal to various circuits is also included in the input section. included in the example.

The communication unit is an interface that connects the MRI apparatus 100, a workstation, a PACS (Picture Archiving and Communication System), a HIS (Hospital Information System), a RIS (Radiology Information System), etc. via a LAN (Local Area Network) or the like. is. The communication unit transmits and receives various information to and from connected workstations, PACS, HIS, and RIS.

Compressor 10 supplies high pressure gas to refrigerator 11 . At this time, the high-pressure gas is supplied to the refrigerator 11 via a cooling pipe connected to the refrigerator 11 . A cooling pipe is, for example, a hose. This cooling pipe may be called a gas hose. The high pressure gas is, for example, high pressure refrigerant gas. Helium gas is preferably used as the refrigerant gas.

The refrigerator 11 cools the static magnetic field magnet 1 . The refrigerator 11 is installed in a state of being coupled to the static magnetic field magnet 1 . The refrigerator 11 adiabatically expands the high-pressure gas supplied from the compressor 10 to generate cold and cool the superconducting coil 1 c in the static magnetic field magnet 1 . Since the refrigerator 11 keeps the static magnetic field magnet 1 always in a superconducting state, the refrigerator 11 continues to operate even when the MRI apparatus 100 is not in operation. As the refrigerator 11, a Gifford-McMahon refrigerator can be preferably used.

The cooling water supply device 101 supplies water adjusted to a predetermined temperature (hereinafter referred to as cooling water) to the cooling water distribution unit 12 in order to cool a device that requires cooling (hereinafter referred to as a cooling target device). do. In addition, the cooling water supply device 101 cools the cooling water returned after being used for cooling the equipment to a predetermined temperature again, and supplies the cooling water adjusted to the predetermined temperature to the cooling water distribution unit 12 again. supply.

A cooling pipe 21 for supplying cooling water to each of the devices to be cooled is connected to the cooling water distribution unit 12 . The cooling water distribution unit 12 is a flow path that distributes the cooling water supplied from the cooling water supply device 101 to each device that requires cooling via the cooling pipes 21 . The devices to be cooled are, for example, the gradient magnetic field coil 2, the transmitter 6, the compressor 10, and the like. The cooling water distributed from the cooling water supply device 101 is returned to the cooling water distribution unit 12 after circulating through each device. The cooling water distribution unit 12 sends the cooling water that has circulated through each device to the cooling water supply device 101 .

A cooling water sensor 13 is attached to the cooling water distribution unit 12 . The cooling water sensor 13 detects information about the flow rate of cooling water flowing inside the cooling water distribution unit 12 (hereinafter referred to as flow rate information), and transmits the detected flow rate information to the computer system 9 . The flow rate information is, for example, the flow velocity [l/min] of cooling water flowing inside the cooling water distribution unit 12 . In this case, as the cooling water sensor 13, a current meter (flow sensor) for measuring the flow velocity of the cooling water is used. The flow rate information may be the temperature of the cooling water flowing inside the cooling water distribution unit 12 or the pressure of the cooling water flowing inside the cooling water distribution unit 12 . In this case, as the coolant sensor 13, a thermometer that measures the temperature of the coolant or a pressure gauge that measures the pressure of the coolant is used. The cooling water sensor 13 may be attached to the cooling water distribution unit 12 or may be installed in a component other than the cooling water distribution unit 12 . Also, the cooling water sensor 13 may be installed independently from the cooling water distribution unit 12 .

A plurality of cooling pipes 22 that circulate inside the gradient magnetic field coil 2 are connected to the cooling water branch portion 14 . The cooling water branching unit 14 branches the cooling water supplied from the cooling water distribution unit 12 to a plurality of cooling pipes 22 directed to the gradient magnetic field coils 2 . The cooling pipe 22 is, for example, a hose. Cooling pipe 22 may be referred to as a water hose. Also, the cooling water branching unit 14 returns the cooling water that has flowed back inside the gradient magnetic field coil 2 to the cooling water distribution unit 12 .

In this way, the cooling water supply device 101, the cooling water distribution unit 12, the cooling pipe 21, the cooling water branching unit 14, and the cooling pipe 22 form cooling means for circulating the cooling water for cooling the gradient magnetic field coil 2.

The reuse water supply unit 15 stores water generated by condensation in the refrigerator 11 (hereinafter referred to as condensed water), and supplies the stored condensed water to the cooling means. Specifically, the reusable water supply unit 15 supplies the condensed water generated by the condensation around the refrigerator 11 installed coupled to the static magnetic field magnet 1 to the cooling water branch unit 14 . The condensed water supplied to the cooling water branching unit 14 is sent to the cooling water supply device 101 via the cooling water distribution unit 12 . The condensed water is cooled to a predetermined temperature in the cooling water supply device 101, then supplied to each device requiring cooling via the cooling water distribution unit 12, and reused as cooling water. The reuse water supply unit 15 corresponds to a condensed water supply unit.

FIG. 2 is a schematic diagram showing components installed in an imaging room among components of the MRI apparatus 100. As shown in FIG.

The cooling pipe 21 includes an outward pipe 21a and a return pipe 21b. One end of the outbound pipe 21 a is connected to the cooling water distribution portion 12 , and the other end of the outbound pipe 21 a is connected to the cooling water branch portion 14 . The outward pipe 21a is a flow path through which cooling water supplied from the cooling water distribution unit 12 to the cooling water branching unit 14 flows. One end of the return pipe 21b is connected to the cooling water distribution portion 12, and the other end of the return pipe 21b is connected to the cooling water branch portion . The return pipe 21b is a flow path through which the cooling water returning from the cooling water branching portion 14 to the cooling water distribution portion 12 flows. The forward pipe 21a and the return pipe 21b are, for example, hoses. The forward pipe 21a and the return pipe 21b may be called water hoses.

The cooling pipe 22 includes an outward pipe 22a and a return pipe 22b. One end of the forward pipe 22a is connected to the forward branch 14a. The outbound pipe 22a is a flow path through which cooling water flows from the outbound branch portion 14a toward the gradient magnetic field coil 2 . One end of the return pipe 22b is connected to the return branch 14b. The return path branch portion 14b is a flow path through which cooling water that has circulated in the gradient magnetic field coil 2 returns to the return path branch portion 14b. The outward pipe 22a and the return pipe 22b are, for example, hoses. The forward pipe 22a and the return pipe 22b may be called water hoses. In FIG. 2, only one of a plurality of outbound pipes 22a extending from the cooling water branch portion 14 to each cooling target device is illustrated, and the other outbound pipes 22a are omitted. Further, only one of a plurality of return pipes 22b that return from each cooling target device to the cooling water branch portion 14 is illustrated, and the other return pipes 22b are omitted.

The cooling water branching portion 14 includes an outward branching portion 14a and a return branching portion 14b. An outbound pipe 21a and a plurality of outbound pipes 22a are connected to the outbound branch portion 14a. The outgoing path branching section 14a branches the cooling water supplied from the cooling water distributing section 12 through the outgoing path pipe 21a into a plurality of outgoing path pipes 22a directed to respective cooling target devices. A return pipe 21b and a plurality of return pipes 21b are connected to the return pipe 14b. The cooling water that has circulated through the devices to be cooled joins at the return path branch portion 14b. The cooling water merged at the return path branch portion 14b is returned to the cooling water distribution portion 12 via the return path pipe 21b.

A refrigerator 11 is attached to the top of the static magnetic field magnet 1 . The refrigerator 11 is installed above the static magnetic field magnet 1 while being covered with a protective case. Further, the refrigerator 11 is attached above the cooling water branching portion 14 . More specifically, the refrigerator 11 and a protective case covering the refrigerator 11 are installed in a portion of the housing of the static magnetic field magnet 1 above the cooling water branch portion 14 . The protective case is exposed to the air in the imaging room. Condensed water may occur on the outer surface of the protective case around the refrigerator 11 .

A water receiving portion 23 is attached to the outer wall of the static magnetic field magnet 1 . The water receiver 23 is provided below the refrigerator 11 . Condensed water generated on the outer surface of the protective case covering the refrigerator 11 temporarily stays in the water receiving portion 23 . The water receiving part 23 is formed in a tray shape, for example. The shape of the water receiving portion 23 is not limited to a tray shape, and may be formed in a shape that prevents condensation water generated in the vicinity of the refrigerator 11 from flowing out to the surroundings.

The reused water supply unit 15 is connected to the water receiving unit 23 via the drain 24 . Drain 24 is, for example, a tube or water hose. A hole for connection with the drain 24 is provided in the bottom surface of the water receiving portion 23 . The water receiving portion 23 is provided at a position higher than the reuse water supply portion 15 . Therefore, the condensed water remaining in the water receiving portion 23 enters the inside of the drain 24 by its own weight and automatically flows into the reused water supply portion 15 through the inside of the drain 24 .

Also, the reuse water supply unit 15 is connected to the cooling water branch unit 14 . The reused water supply unit 15 supplies dew condensation water generated on the outer surface of the protective case covering the refrigerator 11 to the cooling water branch unit 14 as reused water. The condensed water that has flowed into the reused water supply unit 15 through the drain 24 is hereinafter referred to as reused water.

The pressure of the cooling water flowing inside the return path branching portion 14b becomes lower than the pressure of the cooling water flowing inside the outgoing path branching portion 14a. For this reason, it is preferable that the reuse water supply unit 15 is attached to the upper side of the return path branching unit 14b. In this case, compared with the case where the reused water supply unit 15 is attached to the outgoing path branching portion 14a, it becomes easier for the reused water to flow into the cooling water branching portion 14. FIG. In this embodiment, a case where the reuse water supply unit 15 is attached to the return path branching unit 14b will be described as an example. Note that the reused water supply unit 15 may be attached to the outgoing route branching unit 14a.

The reuse water supply unit 15 includes a water storage unit 15a, a coupling unit 15b, and a control unit 15c.

In the water storage portion 15a, reused water that has flowed from the water receiving portion 23 through the drain 24 is stored. The water storage part 15a is formed, for example, in a substantially cylindrical shape with an open top and a bottom. The water reservoir 15a is formed using, for example, a plastic container. The water storage part 15a is preferably made of a transparent material so that the level and amount of reused water can be easily seen from the outside. Moreover, it is preferable that the water storage part 15a is provided with a filter for removing impurities in the reused water.

The water storage unit 15a includes a water storage sensor. The water storage sensor is a sensor that detects information about the amount of reused water stored in the water storage section 15a (hereinafter referred to as water storage information). The stored water information is, for example, the water level [cm] of the reused water. In this case, a water level sensor that detects the level of the reused water stored in the water storage section 15a is used as the water storage sensor. Alternatively, the weight of the recycled water may be used as the stored water information. In this case, a weight sensor that detects the weight of the reused water stored in the water storage portion 15a is used as the water storage sensor.

The coupling portion 15b connects between the water storage portion 15a and the return path branch portion 14b. The connecting portion 15b is provided at the bottom of the water storage portion 15a and attached to the return path branch portion 14b from above. The connecting portion 15b has an on-off valve. A known non-magnetic electromagnetic valve or the like can be suitably used as the on-off valve. When the on-off valve is closed, the reused water stored in the water storage portion 15a does not flow into the return path branch portion 14b. On the other hand, when the on-off valve is open, the reused water stored in the water storage portion 15a flows into the return path branch portion 14b. The on-off valve is preferably a check valve that prevents the cooling water from flowing into the water storage portion 15a from the return path branch portion 14b. Also, the on-off valve may be a double-structured on-off valve.

The control unit 15c is, for example, an IC (Integrated Circuit) chip. The controller 15c is attached to, for example, the outer wall of the water reservoir 15a. The controller 15c is electrically connected to the computer system 9, the water storage sensor, the cooling water sensor 13, and the on-off valve. The connection method between the control unit 15c and each device may be a wired connection or a wireless connection.

Based on the amount of condensed water stored in the water reservoir 15a, the control unit 15c switches whether to supply the condensed water to the cooling means. Specifically, the control unit 15c controls the supply state of reuse water to the cooling means based on the input signal from the computer system 9 and the detection result of the water storage sensor. For example, the controller 15c supplies reused water to the cooling means when the amount of reused water stored in the water reservoir 15a is larger than a predetermined value. Further, the control unit 15c switches whether or not to supply condensed water to the cooling means based on the amount of stored condensed water and whether or not cooling water is circulated. Specifically, the control unit 15c controls the supply state of reused water to the cooling means based on the input signal from the computer system 9, the detection result of the water storage sensor, and the detection result of the cooling water sensor 13. . For example, the control unit 15c supplies reused water to the cooling means when the cooling water is not circulating.

The MRI apparatus 100 also includes a relay board 25 that relays wireless communication between the computer system 9 arranged in the computer room and each device included in the MRI apparatus 100 . When wirelessly connecting the control unit 15c and the computer system 9, it is preferable to connect the control unit 15c and the relay board 25 by wire. In this case, the control unit 15c and the computer system 9 can be wirelessly connected via the relay board 25 without providing a new connection cable or the like.

FIG. 3 is a diagram showing an example of the configuration of the control section 15c. As shown in FIG. 3, the control unit 15c has a processing circuit 151, a memory 152, and a communication interface 153. FIG.

The processing circuit 151 has a processor such as a CPU as a hardware resource. The processing circuit 151 acquires water storage information from the water storage sensor of the water storage section 15a. The processing circuit 151 also acquires flow rate information from the cooling water sensor 13 of the cooling water distribution unit 12 . The processing circuit 151 determines whether or not to supply the condensed water stored in the water storage portion 15a to the cooling water flow path as reused water based on the acquired water storage information and flow rate information, and based on the determination result. Controls the open/close state of the on-off valve.

The memory 152 is a storage device that stores various information. For example, the memory 152 stores an on-off valve control program and the like.

The communication interface 153 is an interface that connects the control unit 15c with the computer system 9, the water storage sensor, the cooling water sensor 13, the solenoid valve, and the like. The communication interface 153 transmits and receives various types of information to and from a connected device.

Next, the operation of the reuse water supply process executed by the MRI apparatus 100 will be described. The reuse water supply process is a process of supplying dew condensation water generated around the refrigerator 11 to the cooling water circulation mechanism as reuse water. FIG. 4 is a flow chart showing an example of the procedure of the reuse water supply process. In FIG. 4, as an example, a case where the reuse water supply process is executed when the MRI system 200 is started up will be described. A case where the reused water supply process is executed at a time other than when the MRI system 200 is started up will be described in another embodiment below. In addition, in FIG. 4, as an example, a case will be described in which the water level of reused water is used as stored water information, and the flow rate of cooling water is used as flow rate information. It should be noted that the processing procedure in each processing described below is merely an example, and each processing can be changed as appropriate as possible. Further, in the processing procedures described below, steps can be omitted, replaced, and added as appropriate according to the embodiment.

(reuse water supply treatment)
(Step S101)
When an operator such as an engineer presses the system activation button of the computer system 9, the system power of the MRI system 200 is turned on and the MRI system 200 is activated. The processing circuitry of the computer system 9 initiates control of the MRI system 200 as a whole.

(Step S102)
The processing circuit of the computer system 9 starts energizing the reuse water supply unit 15 . As a result, the water level sensor of the water reservoir 15a, the electromagnetic valve of the joint 15b, and the controller 15c start to operate.

(Step S103)
The processing circuit 151 of the control unit 15c continuously acquires the water level of the reused water stored in the water storage unit 15a from the water level sensor as water storage information. The control unit 15c determines whether the acquired water level is greater than the first threshold. The first threshold is preset. The first threshold is, for example, the upper limit of the water level. The first threshold value is set to, for example, 4/5 of the height (depth) of the entire water reservoir 15a. If the water level is higher than the first threshold (step S103-Yes), the control unit 15c determines that a large amount of reused water is stored in the water storage unit 15a. In this case, the process proceeds to step S104. On the other hand, if the water level is equal to or lower than the first threshold (step S103-No), the control unit 15c determines that the amount of reused water stored in the water storage unit 15a is small. In this case, the process proceeds to step S109.

(Step S104)
If the water level is greater than the first threshold (step S103-Yes), the processing circuit 151 of the control unit 15c, via the computer system 9, detects the flow rate of cooling water flowing through the cooling water distribution unit 12 from the cooling water sensor 13. get. The control unit 15c determines whether cooling water is flowing inside the cooling water distribution unit 12 based on the obtained flow velocity of the cooling water. That is, the control unit 15c determines whether or not the flow rate of cooling water is present based on the flow velocity of the cooling water inside the cooling water distribution unit 12 . When the cooling water flow rate is 0 (step S104-No), the control unit 15c determines that there is no cooling water flow rate, and determines that the MRI system 200 is not in the imaging state at that time. In this case, the process proceeds to step S105. On the other hand, if the cooling water flow rate is greater than 0 (step S104-Yes), the control unit 15c determines that there is cooling water flow rate, and determines that the MRI system 200 is in the imaging state. In this case, the process proceeds to step S109.

(Step S105)
If there is no cooling water flow (step S104-No), the processing circuit 151 of the control unit 15c opens the solenoid valve of the coupling unit 15b.

(Step S106)
When the flow rate of the cooling water inside the cooling water distribution portion 12 is 0, the flow rate of the cooling water inside the return path branch portion 14b is also 0. Therefore, the reused water stored in the water storage portion 15a flows into the return path branch portion 14b through the opened solenoid valve. If it is difficult for the reused water to flow into the return path branching portion 14b, a known non-magnetic actuator may be provided in the water storage portion 15a. In this case, the actuator is driven in synchronism with the opening of the electromagnetic valve, so that the reusable water can reliably flow from the water storage portion 15a into the return path branch portion 14b.

(Step S107)
When the reused water stored in the water storage portion 15a flows into the return path branch portion 14b, the water level of the reused water stored in the water storage portion 15a gradually decreases. The processing circuit 151 of the control unit 15c determines whether the water level obtained from the water level sensor is smaller than the second threshold. The second threshold is preset. The second threshold is a value less than or equal to the first threshold. The second threshold is, for example, the lower limit of the water level. The second threshold value is set, for example, to a value that is ⅕ of the height (depth) of the entire water reservoir 15a. If the water level is lower than the second threshold (step S107-Yes), the control unit 15c determines that the reusable water has sufficiently flowed from the water storage unit 15a into the return path branching unit 14b. In this case, the process proceeds to step S108. On the other hand, if the water level is equal to or higher than the second threshold (step S107-No), the control unit 15c determines that the amount of reused water stored in the water storage unit 15a is large, and until the water level becomes lower than the second threshold, The process of step S107 is repeated every few seconds, for example.

(Step S108)
If the water level is lower than the second threshold (step S107-Yes), the processing circuit 151 of the control section 15c closes the electromagnetic valve of the coupling section 15b. After that, the controller 15c transmits a signal to the computer system 9 indicating that the electromagnetic valve has been closed.

(Step S109)
Upon receiving a signal indicating that the electromagnetic valve has been closed from the control unit 15c, the processing circuit of the computer system 9 terminates energization of the reused water supply unit 15 and terminates the reused water supply process.

By collecting the condensed water stored when the MRI system 200 is started up in this way, it is possible to prevent the condensed water generated around the refrigerator 11 from affecting surrounding devices during imaging by the MRI system 200. can be prevented.

It should be noted that the above-described reuse water supply process is preferably executed after starting the MRI system 200 and before starting circulation of the cooling water. For example, it is preferable to set a delay time for performing the reuse water supply process. In this case, when the MRI system 200 is activated, the computer system 9 sets a delay time for performing the reuse water supply process before starting circulation of cooling water. The delay time is set to 30 seconds or 1 minute, for example. The control unit 15c completes the reuse water supply process during the delay time. When the reusable water supply process ends, the energization of the reusable water supply unit 15 ends, so that when imaging is performed after the reusable water supply process, the MRI apparatus is caused by energizing the electromagnetic valve or the like. 100 can suppress the influence on the magnetic field.

The effects of the MRI apparatus 100 according to this embodiment will be described below.

As a method for recovering the condensed water generated around the refrigerator 11, for example, a water recovery mechanism is installed so as to surround the refrigerator, and a water recovery container for temporarily storing the condensed water supplied from the water recovery mechanism is used for MRI. A method of installation within the cover of the device is conceivable. However, in such a method, it is necessary to periodically drain the condensed water stored in the water recovery container. Furthermore, since it is necessary to manually transport the water collection container containing the dew condensation water, there is a risk that the water will spill out and splash on the peripheral equipment when the water collection container is transported. In addition, when a refrigerator 11 having a high cooling capacity such as a conduction cooling system is used, the amount of condensed water generated around the refrigerator 11 increases. In this case, it is necessary to increase the size of the water collection container for collecting the condensed water, but there is a possibility that the water collection container cannot be accommodated within the cover of the MRI apparatus.

The MRI apparatus 100 according to the present embodiment includes a static magnetic field magnet 1 that generates a static magnetic field, a refrigerator 11 that cools the static magnetic field magnet 1, a gradient magnetic field coil 2 that generates a gradient magnetic field, and a gradient magnetic field coil 2 that cools the and a reusable water supply unit 15 . The reuse water supply unit 15 can store the condensed water generated in the refrigerator 11 and supply the stored condensed water to the cooling means. Further, the reuse water supply unit 15 can switch whether or not to supply the condensed water to the cooling means based on the amount of the stored condensed water.

With the above configuration, according to the MRI apparatus 100 according to the present embodiment, by supplying the condensed water generated by condensation around the refrigerator 11 to the cooling means, the condensed water is reused as cooling water without being discharged. be able to. In addition, since the condensed water can be collected automatically without human intervention, it is possible to avoid the risk associated with transporting a container in which the condensed water is stored. In addition, since the stored dew condensation water is sequentially supplied to the cooling means, the water storage portion 15a of the reusable water supply portion 15 can be made small.

Further, the reuse water supply unit 15 includes a water storage unit 15a that stores the condensed water generated in the refrigerator 11. When the amount of condensed water stored in the water storage unit 15a is larger than the first threshold value, the water condenses on the cooling means. water can be supplied.

The reused water supply unit 15 also includes a water storage sensor that detects the level, volume, or weight of the stored condensed water, and acquires the amount of condensed water stored in the water storage unit 15a based on the detection result of the water storage sensor. .

With the above configuration, the MRI apparatus 100 according to the present embodiment can supply the accumulated dew condensation water to the cooling means every time a certain amount of the dew condensation water accumulates. Thereby, the accumulated dew condensation water can be efficiently supplied to the cooling means. In addition, it is possible to prevent excessive accumulation of condensed water in the water storage portion 15a of the reuse water supply portion 15. FIG.

In order to cool the gradient magnetic field coil 2 during imaging, cooling water circulates inside the gradient magnetic field coil 2 . Therefore, for example, when the condensed water stored in the water storage portion 15a is supplied to the cooling water branching portion 14 at the time of photographing, the pressure of the cooling water flowing inside the cooling water branching portion 14 causes the condensed water to flow into the cooling water branching portion 14. is difficult to enter. Further, when the electromagnetic valve is opened and closed during imaging, the magnetic field of the MRI apparatus 100 may be affected.

In this embodiment, the reuse water supply unit 15 can switch whether or not to supply condensed water to the cooling means based on the amount of stored condensed water and whether or not cooling water is circulated. Specifically, when the amount of condensed water stored in the water reservoir 15a is greater than the first threshold value and the cooling water is not circulating, the reused water supply unit 15 supplies the condensed water to the cooling means. be able to.

The reuse water supply unit 15 also includes a cooling water sensor 13 that detects the flow rate of cooling water, and a control unit 15c. The control unit 15c can determine whether cooling water is circulating based on the detection result of the cooling water sensor 13, and can control the supply state of condensed water to the cooling means based on the determination result.

With the above configuration, according to the MRI apparatus 100 according to the present embodiment, the presence or absence of cooling water flowing inside the cooling water branch portion 14 is detected, and dew condensation water is supplied to the cooling means only when the cooling water is not circulating. By doing so, it is possible to prevent the electromagnetic valve from opening and closing during photographing. Further, by supplying the condensed water to the cooling means only when the cooling water is not circulating, it is possible to prevent the condensed water from flowing in a state where it is difficult for the condensed water to flow due to the flow of the cooling water. Condensed water can be recovered as reused water.

(Second embodiment)
A second embodiment will be described. This embodiment is obtained by modifying the configuration of the first embodiment as follows. Descriptions of the same configurations, operations, and effects as in the first embodiment are omitted. The MRI apparatus 100 according to this embodiment determines whether there is a patient in the gradient magnetic field coil 2 based on the image acquired from the camera, and whether the MRI system 200 is in an imaging state based on the determination result of the presence or absence of the patient. determine whether or not

In this embodiment, the MRI apparatus 100 includes a patient camera (not shown). A patient camera is, for example, a general camera that generates an image by photographing an object to be photographed. The patient camera is provided at a position where the state of the top plate 4 placed inside the gradient magnetic field coil 2 can be photographed.

The computer system 9 acquires an image captured by a patient camera (hereinafter referred to as a camera image), and extracts a patient from the camera image by performing image processing and determination processing on the camera image. Then, the computer system 9 determines whether or not there is a patient in the gradient coil 2 based on the patient extraction result.

The patient camera and computer system 9 are an example of identification means for identifying the presence or absence of a subject within the gradient magnetic field coil 2 .

The control unit 15c acquires information about the presence or absence of a patient inside the gradient magnetic field coil 2 from the computer system 9 . Then, the control unit 15c controls the opening/closing state of the opening/closing valve of the coupling unit 15b based on the acquired water storage information, flow rate information, and information regarding the presence or absence of a patient, thereby controlling the supply state of condensed water to the cooling means. Control. Specifically, based on the flow rate information and information on the presence or absence of a patient, the control unit 15c determines whether the cooling water is not circulating, or when the cooling water is circulating and the gradient magnetic field coil 2 is affected. When the specimen does not exist, it is determined that the MRI system 200 is not in the imaging state, and the dew condensation water stored in the water storage section 15a is supplied to the cooling means as reused water.

(reuse water supply treatment)
Next, the operation of the reuse water supply process executed by the MRI apparatus 100 of this embodiment will be described. FIG. 5 is a flow chart showing an example of the procedure of the reuse water supply process according to this embodiment. It should be noted that the processing procedure in each processing described below is merely an example, and each processing can be changed as appropriate as possible. Also, in the processing procedure described below, steps can be omitted, replaced, or added as appropriate according to the embodiment. In FIG. 5, as an example, a case where the reuse water supply process is executed when the MRI system 200 is started up will be described. In addition, in FIG. 5, as an example, a case will be described in which the level of recycled water is used as stored water information, and the flow rate of cooling water is used as flow rate information.

The processing of steps S201-S203, S205 and S207-S210 is the same as the processing of steps S101-S103 and S105-S109 in FIG.

(Step S204)
As in the first embodiment, the control unit 15c determines whether or not there is a flow rate of cooling water based on the flow velocity of the cooling water inside the cooling water distribution unit 12 . Then, if the cooling water flow rate is 0 (step S204-No), the control unit 15c determines that there is no cooling water flow rate, and determines that the MRI system 200 is not in the imaging state at that time. In this case, the process proceeds to step S205. On the other hand, if the cooling water flow rate is greater than 0 (step S204-Yes), the controller 15c determines that there is a cooling water flow rate. In this case, the process proceeds to step S206.

(Step S206)
In the process of step S204, if there is a flow rate of cooling water (step S204-Yes), the processing circuit 151 of the control unit 15c acquires information on the presence or absence of a patient from the computer system 9. FIG. Then, the control unit 15c determines whether a patient exists within the gradient magnetic field coil 2 based on the information regarding the presence or absence of the patient. If the patient does not exist within the gradient magnetic field coil 2 (step S206-No), the process proceeds to step S205, and the solenoid valve of the coupling portion 15b is opened. On the other hand, if the patient exists within the gradient magnetic field coil 2 (step S206-Yes), the controller 15c determines that the MRI system 200 is in the imaging state. In this case, the process proceeds to step S210, and energization of the reuse water supply unit 15 ends.

The effects of the MRI apparatus 100 according to this embodiment will be described below. The MRI apparatus 100 according to this embodiment has the following effects in addition to the effects described in the first embodiment.

In the first embodiment, it was determined that imaging was being performed when cooling water was circulating inside the gradient magnetic field coil 2 . However, even when the cooling water is circulating inside the gradient magnetic field coil 2, imaging may not actually be performed.

The MRI apparatus 100 according to this embodiment further includes identification means for identifying the presence or absence of the subject within the gradient magnetic field coil 2 . The controller 15c of the reusable water supply unit 15 can control the state of supplying condensed water to the cooling means based on the amount of stored condensed water and the presence or absence of the subject. Specifically, even when the cooling water is circulating, the control unit 15c of the reuse water supply unit 15 supplies dew condensation water to the cooling means when the subject does not exist in the gradient magnetic field coil 2. can be supplied.

With the above configuration, according to the MRI apparatus 100 according to the present embodiment, cooling water circulates inside the gradient magnetic field coil 2 by using information regarding the presence or absence of a patient obtained from images acquired from a patient camera. Even in such a case, the condensed water can be supplied to the cooling means when the photographing is not actually performed. As a result, it is possible to prevent the solenoid valve from opening and closing during photographing, and to efficiently reuse the condensed water stored in the water storage portion 15a as cooling water.

(Third Embodiment)
A third embodiment will be described. This embodiment is obtained by modifying the configuration of the first embodiment as follows. Descriptions of the same configurations, operations, and effects as in the first embodiment are omitted. In the MRI apparatus 100 according to the present embodiment, the control unit 15c of the reused water supply unit 15 supplies the stored condensed water as reused water to the cooling water flow path when the MRI system 200 is shut down.

(reuse water supply treatment)
Next, the operation of the reuse water supply process executed by the MRI apparatus 100 of this embodiment will be described. FIG. 6 is a flow chart showing an example of the procedure of the reuse water supply process according to this embodiment. It should be noted that the processing procedure in each processing described below is merely an example, and each processing can be changed as appropriate as possible. Further, in the processing procedures described below, steps can be omitted, replaced, and added as appropriate according to the embodiment. In FIG. 6, as an example, a case will be described in which the level of recycled water is used as stored water information and the flow rate of cooling water is used as flow rate information. Further, in this embodiment, the reuse water supply process is executed when the MRI system 200 is shut down.

The processing of steps S303-S309 is the same as the processing of steps S103-S109 in FIG. 4, respectively, and thus the description thereof is omitted.

(Step S301)
When an operator such as a technician presses the system activation button that has already been pressed provided in the computer system 9 again, the processing circuit of the computer system 9 starts a shut-down operation to turn off the system power of the MRI system 200. .

(Step S302)
When the shutdown operation starts, the processing circuit of the computer system 9 starts energizing the reuse water supply unit 15 . As a result, the water level sensor of the water reservoir 15a, the electromagnetic valve of the joint 15b, and the controller 15c start to operate.

(Steps S303-S309)
When energization of the reused water supply unit 15 is disclosed, the control unit 15c of the reused water supply unit 15 controls the reused water level obtained from the water level sensor and the cooling water level, as in the first embodiment. Based on the flow velocity of the cooling water acquired from the sensor 13, the reused water stored in the water storage portion 15a is caused to flow into the return path branch portion 14b. Then, when receiving a signal indicating that the electromagnetic valve has been closed from the control unit 15c, the processing circuit of the computer system 9 terminates energization of the reused water supply unit 15 and terminates the reused water supply process.

It should be noted that the above-described reuse water supply process is preferably executed before power supply to the MRI system 200 is terminated after cooling water circulation is terminated. By starting the energization of the reused water supply unit 15 after the circulation of the cooling water ends, it is possible to reliably suppress the influence on the magnetic field of the MRI apparatus 100 caused by the energization of the solenoid valve and the like. For example, it is preferable to set a delay time for performing the reuse water supply process. In this case, the computer system 9 receives an operation to end the MRI system 200, and when the cooling water circulation ends, it sets a delay time for performing the reuse water supply process. The delay time is set to 30 seconds or 1 minute, for example. The control unit 15c completes the reuse water supply process during the delay time. Then, when the reuse water supply process is completed, the computer system 9 terminates power supply to the MRI system 200 .

The effects of the MRI apparatus 100 according to this embodiment will be described below. The MRI apparatus 100 according to this embodiment has the following effects in addition to the effects described in the first embodiment. According to the MRI apparatus 100 according to the present embodiment, when the MRI system 200 is shut down, the condensed water generated around the refrigerator 11 can be reused as cooling water without being discharged. By collecting the accumulated dew condensation water when the MRI system 200 is shut down, it is possible to prevent the accumulation of condensed water exceeding the capacity of the water receiver 23 until the next use of the MRI system 200 .

(Fourth embodiment)
A fourth embodiment will be described. This embodiment is obtained by modifying the configuration of the first embodiment as follows. Descriptions of the same configurations, operations, and effects as in the first embodiment are omitted. The reusable water supply unit 15 of the MRI apparatus 100 according to the present embodiment automatically switches between supply and non-supply of reusable water to the cooling means using an on-off valve that does not require energization. In other words, the recycled water supply unit 15 controls the amount of recycled water supplied to the cooling means by switching the open/closed state of the on-off valve.

In this embodiment, the reuse water supply unit 15 includes a water storage unit 15a and a coupling unit 15b.

The water storage part 15a is formed, for example, in a substantially cylindrical shape with an open top and a bottom. The water reservoir 15a is formed using, for example, a plastic container. Moreover, the water storage part 15a is provided with a water storage sensor. In this embodiment, as the water storage sensor, a mechanism capable of detecting water storage information is used without power supply. The water storage sensor is, for example, a float-type water level sensor.

The connecting portion 15b has a double structure on-off valve that connects between the water storage portion 15a and the return path branch portion 14b. Specifically, the connecting portion 15b includes an upper opening/closing valve, a lower opening/closing valve arranged below the upper opening/closing valve, and a retention portion provided between the upper opening/closing valve and the lower opening/closing valve. The retention portion is a gap provided between the upper on-off valve and the lower on-off valve. The upper opening/closing valve is connected to the water reservoir 15a. The upper open valve corresponds to the first open valve. The lower opening/closing valve is connected to the return path branch portion 14b. The lower open valve corresponds to the second open valve.

The upper opening/closing valve is connected to a float-type water level sensor provided in the water reservoir 15a. When the upper opening/closing valve is closed, the reusable water stored in the water storage section 15a cannot flow into the retention section. When the upper opening/closing valve is open, the reusable water stored in the water storage section 15a becomes available in the retention section. The upper opening/closing valve is a check valve that prevents the cooling water from flowing from the retention portion to the water storage portion 15a.

The upper opening/closing valve is opened when the amount of condensed water stored in the water storage portion 15a is greater than a predetermined value. For example, when the water level of the reused water stored in the water reservoir 15a exceeds the first threshold while the upper on-off valve is closed, the upper on-off valve is automatically opened. The first threshold is, for example, the upper limit of the water level. The first threshold value is set to, for example, 4/5 of the height (depth) of the entire water reservoir 15a. In addition, when the water level of the reused water stored in the water reservoir 15a becomes higher than the second threshold while the upper opening/closing valve is open, the upper opening/closing valve is automatically closed. The second threshold is a value less than or equal to the first threshold. The second threshold is, for example, the lower limit of the water level. The second threshold value is set, for example, to a value that is ⅕ of the height (depth) of the entire water reservoir 15a.

The lower opening/closing valve is connected to a cooling water flow path passing through the return path branch portion 14b. The lower opening/closing valve is a check valve that prevents the cooling water from flowing into the retention portion from the return path branch portion 14b. For example, a known three-way valve is used as the lower opening/closing valve. When the lower opening/closing valve is closed, the reused water stored in the retention portion cannot flow into the return path branch portion 14b. When the lower opening/closing valve is open, reusable water can flow from the retention portion to the return path branch portion 14b. Therefore, in a state in which both the upper stage on-off valve and the lower stage on-off valve are open, the reused water stored in the water storage section 15a is supplied to the cooling means through the retention section. The coupling portion 15b is arranged so that the flow path of the reused water formed between the water storage portion 15a and the return path branch portion 14b is substantially perpendicular to the cooling water flow path passing through the return path branch portion 14b. It is preferable to be connected to a cooling water flow path passing through the inside of the return path branch portion 14b.

When the cooling water is flowing inside the return path branch portion 14b, that is, when the cooling water is circulating in the cooling means, the lower opening/closing valve is automatically closed by the water flow of the cooling water. Further, when the cooling water does not flow inside the return path branch portion 14b, that is, when the cooling water does not circulate in the cooling means, the lower opening/closing valve is automatically opened.

Note that the lower open valve may not be provided. In this case, when the upper opening/closing valve is open, the reused water stored in the water storage portion 15a is supplied to the cooling means.

Next, the operation of the MRI apparatus 100 of this embodiment will be described. FIG. 7 is a flow chart showing an example of the operation of the MRI apparatus 100 of this embodiment. Note that each operation described below is merely an example, and each operation can be changed as appropriate as possible. Also, with respect to the operations described below, steps can be omitted, replaced, or added as appropriate according to the embodiment.

In the water storage section 15a, the water level of the reused water stored in the water storage section 15a is constantly detected by the float-type water level sensor (step S401).

When the amount of reusable water stored in the water storage portion 15a is small, the upper opening/closing valve is closed. When the water level of the reused water stored in the water storage unit 15a is higher than the first threshold value while the upper on-off valve is closed (step S401-Yes), the upper on-off valve is interlocked with the detection of the water storage sensor of the water storage unit 15a. is automatically opened (S402). When the upper opening/closing valve is open, the reused water stored in the water storage section 15a flows into the retention section.

If cooling water is flowing inside the return path branch portion 14b (step S403-Yes), the lower opening/closing valve is automatically closed by the cooling water flow. When the upper on-off valve is opened and the lower on-off valve is closed, the reusable water that has flowed from the water storage part 15a into the retention part is blocked by the lower on-off valve in the retention part.

When the cooling water does not flow inside the return path branch portion 14b (step S403-No), the lower opening/closing valve is opened (step S404). When the lower opening/closing valve is opened while the upper opening/closing valve is open, the reusable water stored in the water storage portion 15a flows through the retention portion into the return path branch portion 14b, and is stored in the water storage portion 15a. The reused water thus obtained is automatically supplied to the cooling means (step S405).

When the reused water stored in the water storage portion 15a flows into the return path branch portion 14b, the water level of the reused water stored in the water storage portion 15a gradually decreases. Then, when the level of the reused water in the water storage section 15a becomes lower than the second threshold value (step S406-Yes), the upper open valve is automatically closed in conjunction with the detection of the water storage sensor of the water storage section 15a. (Step S407). When the upper open valve is closed, reusable water cannot flow from the water storage section 15a into the retention section, thereby automatically stopping the supply of the reused water stored in the water storage section 15a to the cooling means.

The effects of the MRI apparatus 100 according to this embodiment will be described below.

In the MRI apparatus 100 according to this embodiment, the reuse water supply unit 15 includes an upper opening/closing valve that is opened when the amount of stored dew condensation water is greater than a predetermined value. When the upper opening/closing valve is open, the stored dew condensation water is supplied to the cooling means.

With the above configuration, according to the MRI apparatus 100 according to the present embodiment, by using an on-off valve that automatically switches between open and closed states according to the amount of reused water stored in the water reservoir 15a, the water stored in the water reservoir 15a is The supply state of the reused water to the cooling means can be switched according to the amount of reused water.

Furthermore, in the present embodiment, the supply state of the reused water to the cooling means can be switched without energizing the reused water supply unit 15 . Therefore, the condensed water generated around the refrigerator can be recovered without affecting the magnetic field of the MRI apparatus 100 during imaging.

In addition, in the MRI apparatus 100 according to this embodiment, the reuse water supply unit 15 further includes a lower opening/closing valve that is opened when the cooling water is not circulating. When the first on-off valve is open and the second on-off valve is open, the stored condensed water is supplied to the cooling means.

With the above configuration, according to the MRI apparatus 100 according to the present embodiment, the on-off valve automatically switches between open and closed states according to the amount of reused water stored in the water storage unit 15a, and according to the presence or absence of circulation of cooling water. By using a double-structure opening and closing valve formed by an opening and closing valve that automatically switches between open and closed states, the cooling means can It is possible to switch the supply state of recycled water to

Further, only when a predetermined amount of reusable water is stored in the water reservoir 15a and the cooling water is not circulating, the condensed water stored in the water reservoir 15a can be supplied to the cooling means. Therefore, it is possible to prevent the condensed water from flowing in a state where it is difficult for the condensed water to flow due to the flow of the cooling water, and the condensed water can be efficiently recovered as reused water.

Further, by providing a retention portion between the upper opening/closing valve and the lower opening valve as in the present embodiment, the capacity of the reused water supply portion 15 to retain the reused water can be increased.

According to at least one embodiment described above, it is possible to prevent the condensed water generated around the refrigerator from affecting peripheral devices.

While several embodiments have been described, these embodiments are provided by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations of embodiments can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, as well as the scope of the invention described in the claims and equivalents thereof.

200 MRI system 100 MRI apparatus 101 Cooling water supply device 1 Static magnetic field magnet 1a Vacuum container 1b Refrigerant container 1c Superconducting coil 2 Gradient magnetic field coil 3 High frequency coil 4 Top plate 5 Gradient magnetic field power source 6 Transmitter 7 Receiver 8 Sequence control device 9 Computer system 10 Compressor 11 Refrigerator 12 Cooling water distribution unit 13 Cooling water sensor 14 Cooling water branching unit 14a Forward branching unit 14b Returning branch Part 15... Recycled water supply part 15a... Water storage part 15b... Coupling part 15c... Control part 151... Processing circuit 152... Memory 153... Communication interfaces 21, 22... Cooling pipes 21a, 22a... Forward pipes 21b, 22b... Return pipe 23 ...Water receiving part 24...Drain 25...Relay board

Claims (10)

a superconducting magnet that generates a static magnetic field;
a refrigerator for cooling the superconducting magnet;
a gradient magnetic field coil that generates a gradient magnetic field;
cooling means for circulating cooling water for cooling the gradient magnetic field coil;
a condensed water supply unit that stores condensed water generated in the refrigerator and supplies the stored condensed water to the cooling means;
with
The condensed water supply unit switches whether to supply condensed water to the cooling means based on the amount of the stored condensed water.
Magnetic resonance imaging equipment. The condensed water supply unit supplies the condensed water to the cooling means when the amount of the stored condensed water is greater than a predetermined value.
The magnetic resonance imaging apparatus according to claim 1. The condensed water supply unit includes a water storage sensor that detects the amount of the stored condensed water, and a control unit that controls the supply state of the condensed water to the cooling means based on the detection result of the water storage sensor.
3. The magnetic resonance imaging apparatus according to claim 2. The condensed water supply unit switches whether or not to supply condensed water to the cooling means based on the amount of the stored condensed water and whether or not the cooling water is circulated.
A magnetic resonance imaging apparatus according to any one of claims 1 to 3. The condensed water supply unit supplies condensed water to the cooling means when the cooling water is not circulating.
5. The magnetic resonance imaging apparatus according to claim 4. The cooling means includes a cooling water sensor that detects the flow rate of the cooling water,
The condensed water supply unit determines whether or not the cooling water is circulated based on the detection result of the cooling water sensor, and controls the supply state of the condensed water to the cooling means based on the determination result. prepare
6. A magnetic resonance imaging apparatus according to claim 5. Further comprising identification means for identifying the presence or absence of the subject within the gradient magnetic field coil,
The control unit controls the supply state of the condensed water to the cooling means based on the amount of the stored condensed water, the presence or absence of circulation of the cooling water, and the presence or absence of the subject.
7. A magnetic resonance imaging apparatus according to claim 6. The control unit supplies condensed water to the cooling means when the cooling water is not circulating, or when the cooling water is circulating and the subject does not exist in the gradient magnetic field coil. do,
The magnetic resonance imaging apparatus according to claim 7. The condensed water supply unit includes a first on-off valve that is opened when the amount of the stored condensed water is greater than a predetermined value,
When the first on-off valve is open, the stored condensed water is supplied to the cooling means.
The magnetic resonance imaging apparatus according to claim 1. The condensed water supply unit further includes a second on-off valve that is opened when cooling water is not circulating,
When the first on-off valve is open and the second on-off valve is open, the stored condensed water is supplied to the cooling means.
A magnetic resonance imaging apparatus according to claim 9 .

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