JP5450133B2 - Magnetic resonance imaging system - Google Patents

Description

  The present invention relates to a magnetic resonance imaging apparatus.

  2. Description of the Related Art A magnetic resonance imaging (MRI) apparatus is an apparatus that images a subject using a 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. Various devices necessary for imaging the inside of the specimen are provided. Some of these devices require cooling because they generate heat during operation. Therefore, conventionally, there has been a cooling technique for cooling each device by circulating a coolant such as cooling water through the device included in the MRI apparatus (see, for example, Patent Document 1).

  Note that some of the devices that require cooling here include those that require constant cooling and those that require cooling only while the MRI apparatus is operating. A device that requires constant cooling is, for example, a device that continues to operate while the MRI apparatus is not operating. An example of such an apparatus is a refrigerator for cooling a refrigerant (such as liquid helium) of a superconducting magnet used as a static magnetic field magnet. On the other hand, the device that needs to be cooled only while the MRI apparatus is operating is, for example, an apparatus whose operation is stopped while the MRI apparatus is not operating. Examples of such devices include gradient magnetic field coils and gradient magnetic field power supplies.

  However, the cooling technique described above generally circulates the refrigerant through all the devices to be cooled regardless of the operating state of the MRI apparatus. Therefore, while the MRI apparatus is not operating, the cooling water is circulated also to the equipment that has stopped operating, that is, the equipment that does not require cooling. As a result, for example, when the difference between the room temperature of the room where the MRI apparatus is installed and the water temperature of the cooling water becomes large at night or the like, there is a possibility that condensation occurs on the equipment whose operation is stopped.

  It is known that condensation can be a significant cause of equipment failure. Therefore, for example, while the MRI apparatus is not operating, the room temperature of the room where the MRI apparatus is installed is adjusted to a temperature at which no condensation occurs by operating an air conditioner such as an air conditioner. In addition, a dew condensation prevention system that prevents dew condensation by warming a device in which a refrigerant is circulated may be used in preparation for failure of an air conditioner.

JP 2009-240765 A

  However, in the above-described conventional technology, electric power is consumed to operate the air conditioning apparatus and the dew condensation prevention system described above while the MRI apparatus is not operating. On the other hand, there has been a request from the user of the MRI apparatus to reduce the amount of power consumed while the MRI apparatus is not operating in order to save energy.

  The present invention has been made in view of the above, and provides a magnetic resonance imaging apparatus capable of preventing condensation that occurs in an apparatus while suppressing the amount of power consumed while the MRI apparatus is not operating. For the purpose.

  In order to solve the above-described problems and achieve the object, the present invention according to claim 1 is directed to a magnetic resonance imaging apparatus in which a first apparatus that requires constant cooling and cooling only while the apparatus is in operation. A required second device, and a refrigerant distribution unit that distributes the refrigerant supplied by the refrigerant supply unit to the first device and the second device, wherein the refrigerant distribution unit has an apparatus powered on. During the period, the refrigerant is distributed to each of the first device and the second device, and when the power source is changed from on to off, the distribution of the refrigerant to the second device is stopped. To do.

  According to the first aspect of the present invention, it is possible to prevent the dew condensation that occurs in the equipment while suppressing the amount of power consumed while the MRI apparatus is not operating.

FIG. 1 is a configuration diagram illustrating the configuration of the MRI apparatus according to the first embodiment. FIG. 2 is a block diagram illustrating the configuration of the cooling water distribution unit according to the first embodiment. FIG. 3 is a diagram (1) for explaining the switching of the flow paths in the cooling water distribution unit according to the first embodiment. FIG. 4 is a diagram (2) for explaining the switching of the flow paths in the cooling water distribution unit according to the first embodiment. FIG. 5 is a flowchart illustrating the operation procedure of the cooling water distributor according to the first embodiment. FIG. 6 is a block diagram illustrating the configuration of the cooling water distribution unit according to the second embodiment. FIG. 7 is a diagram (1) for explaining the flow path switching in the cooling water distribution unit according to the second embodiment. FIG. 8 is a diagram (2) illustrating the switching of the flow paths in the cooling water distribution unit according to the second embodiment. FIG. 9 is a flowchart illustrating the operation procedure of the cooling water distributor according to the second embodiment.

  Embodiments of an MRI apparatus according to the present invention will be described below in detail with reference to the drawings. In the following embodiment, a case where cooling water is used as a refrigerant for cooling each device included in the MRI apparatus will be described.

  First, the configuration of the MRI apparatus 100 according to the first embodiment will be described. FIG. 1 is a configuration diagram illustrating the configuration of the MRI apparatus 100 according to the first embodiment. As shown in FIG. 1, an 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 transmission unit 6, a reception unit 7, a sequence control device 8, and a computer system. 9, a refrigerator 10, a cooling water distributor 11, and a cooling water supply device 12.

  For example, the static magnetic field magnet 1, the gradient magnetic field coil 2, the high frequency coil 3, and the top plate 4 are installed in the photographing room. Further, for example, the gradient magnetic field power supply 5, the transmission unit 6, the reception unit 7, the sequence control device 8, the computer system 9, the refrigerator 10, and the cooling water distribution unit 11 are installed in the computer room. For example, the cooling water supply device 12 is installed outdoors.

  The static magnetic field magnet 1 generates a static magnetic field in the imaging region where the subject P is placed. For example, the static magnetic field magnet 1 includes a vacuum container 1a, a refrigerant container 1b, and a superconducting coil 1c. The vacuum vessel 1a is formed in a substantially cylindrical shape, and the inside of the cylindrical wall is kept in a vacuum state. A space formed inside the vacuum container 1a is an imaging region where the subject P is placed. The refrigerant container 1b is formed in a substantially cylindrical shape, and is stored in the cylindrical wall of the vacuum container 1a. As a general example, the refrigerant container 1b contains liquid helium as a refrigerant in the cylindrical wall in order to keep the inside of the container at a sufficiently low temperature. Superconducting coil 1c is disposed in the cylindrical wall of refrigerant container 1b and is immersed in liquid helium. The superconducting coil 1c generates a static magnetic field in the imaging region inside the vacuum vessel 1a.

  The gradient coil 2 is formed in a substantially cylindrical shape and is disposed inside the static magnetic field magnet 1. The gradient magnetic field coil 2 generates a gradient magnetic field in the X-axis, Y-axis, and Z-axis directions set in the imaging region by a current supplied from the gradient magnetic field power supply 5. The gradient magnetic field coil 2 generates heat because a pulse current is repeatedly supplied during execution of scanning.

  The high frequency coil 3 is disposed inside the gradient magnetic field coil 2. The high frequency coil 3 irradiates the subject P placed in the imaging region with a high frequency pulse transmitted from the transmission unit 6. The high-frequency coil 3 receives a magnetic resonance signal emitted from the subject P by excitation of hydrogen nuclei by a high-frequency pulse.

  The top plate 4 is supported by a bed (not shown). In addition, the subject 4 is placed on the top 4 at the time of imaging, and is moved into the imaging region together with the subject P.

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

  The transmission unit 6 transmits a high frequency pulse to the high frequency coil 3 based on an instruction from the sequence control device 8. The transmitter 6 has a high frequency power source for generating a high frequency pulse to be transmitted to the high frequency coil 3. This high frequency power source generates heat during the execution of scanning.

  The receiving unit 7 detects the magnetic resonance signal received by the high-frequency coil 3, and generates raw data by digitizing the detected magnetic resonance signal. Then, the reception unit 7 transmits the generated raw data to the sequence control device 8.

  The sequence control device 8 scans the subject P by driving the gradient magnetic field power supply 5, the transmission unit 6, and the reception unit 7 under the control of the computer system 9. Then, when the raw data is transmitted from the receiving unit 7 as a result of the scan, the sequence control device 8 transmits the raw data to the computer system 9.

  The computer system 9 controls the entire MRI apparatus 100 based on an operation performed by an operator. For example, the computer system 9 includes an input unit, a display unit, a sequence control unit, an image reconstruction unit, a storage unit, a display unit, a main control unit, and the like. The input unit accepts various inputs from the operator. The display unit displays various information including an image of the subject. The sequence control unit causes the sequence control device 8 to perform scanning based on the imaging conditions input from the operator. The image reconstruction unit reconstructs an image of the subject P based on the raw data transmitted from the sequence control device 8. The storage unit stores the reconstructed image and the like. The main control unit controls the operation of each functional unit based on an instruction from the operator.

  The refrigerator 10 cools the superconducting coil 1 c in the static magnetic field magnet 1. As a general example, the refrigerator 10 cools the superconducting coil 1 c through liquid helium filled in the static magnetic field magnet 1. The refrigerator 10 is continuously operated even when the MRI apparatus 100 is not operating so that the static magnetic field magnet 1 is always kept in a superconductive state.

  The cooling water distributor 11 distributes the cooling water supplied from the cooling water supply device 12 to each device that needs to be cooled. For example, when the cooling water is sent from the cooling water supply device 12, the cooling water distributor 11 distributes the cooling water to each cooling pipe provided in each device that needs to be cooled. Moreover, the cooling water distribution part 11 will send the cooling water to the cooling water supply apparatus 12, if the cooling water which circulated through each apparatus is returned from each apparatus. The cooling water distributor 11 will be described in detail later.

  The cooling water supply device 12 supplies the cooling water to the cooling water distributor 11. For example, the cooling water supply device 12 sends the cooling water adjusted to a predetermined temperature to the cooling water distributor 11. In addition, when the cooling water is returned from the cooling water distributor 11, the cooling water supply device 12 cools the cooling water to a predetermined temperature and then sends it to the cooling water distributor 11.

  Here, each of the above-described devices includes a device that requires constant cooling (first device) and a device that requires cooling only while the MRI apparatus 100 is operating (second device). It is. For example, since the refrigerator 10 continues to operate while the MRI apparatus 100 is not operating, it needs to be constantly cooled. Further, for example, since the operation of the gradient magnetic field coil 2, the gradient magnetic field power source 5 and the transmission unit 6 is stopped while the MRI apparatus 100 is not operating, cooling is necessary only while the MRI apparatus 100 is operating. is there. Each device that needs to be cooled is provided with a cooling pipe for circulating the cooling water sent from the cooling water distributor 11 to the devices.

  In such a configuration, in the first embodiment, the cooling water distribution unit 11 distributes the cooling water to each device that needs to be cooled while the power of the MRI apparatus 100 is on. In addition, when the power of the MRI apparatus 100 is changed from on to off, the cooling water distribution unit 11 stops the distribution of the cooling water to the apparatus that needs to be cooled only while the MRI apparatus 100 is operating.

  That is, in the first embodiment, while the MRI apparatus 100 is not in operation, the cooling water is circulated only to the equipment that needs to be constantly cooled, and the cooling water is supplied to the equipment that has stopped operating, that is, the equipment that does not require cooling. Is not circulated. For this reason, for example, even when the difference between the room temperature of the room where the MRI apparatus 100 is installed and the water temperature of the cooling water becomes large at night or the like, dew condensation does not occur in the equipment whose operation is stopped. For this reason, it is not necessary to operate the air conditioning equipment or the dew condensation prevention system while the MRI apparatus 100 is not operating. Therefore, according to the first embodiment, it is possible to prevent dew condensation that occurs in the device while suppressing the amount of power consumed while the MRI apparatus 100 is not operating.

  Below, cooling of each apparatus by the cooling water distribution part 11 is demonstrated in detail. In the first embodiment, the case where the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 are cooled will be described.

  First, the configuration of the cooling water distributor 11 according to the first embodiment will be described. FIG. 2 is a block diagram illustrating the configuration of the cooling water distributor 11 according to the first embodiment. 3 and 4 are diagrams for explaining the switching of the flow paths in the cooling water distributor 11 according to the first embodiment.

  As shown in FIG. 2, the cooling water distributor 11 is connected to the computer system 9 via a control terminal 11a. An insulating transformer 13 is inserted between the computer system 9 and the control terminal 11a.

  The insulating transformer 13 insulates the cooling water distributor 11 from the computer system 9. As described above, the insulation transformer 13 insulates the cooling water distribution unit 11 from the computer system 9, so that even if a leakage occurs in the cooling water distribution unit 11 due to water leakage or the like, the leaked current flows into the computer system 9. Therefore, the computer system 9 is kept in a safe state.

  The computer system 9 controls the power supply of the MRI apparatus 100 and transmits the power supply state to the cooling water distributor 11. For example, the computer system 9 is an MRI apparatus except for an apparatus that needs to continue operation even when the MRI apparatus 100 is not in operation when the operator performs an operation to turn off the power of the MRI apparatus 100. Control is performed so that power supply to each device included in 100 stops.

  Further, the computer system 9 supplies a current to the control terminal 11a after the operation for turning on the power of the MRI apparatus 100 is performed by the operator, thereby confirming that the power of the MRI apparatus is on. This is transmitted to the distribution unit 11. The computer system 9 also confirms that the power supply of the MRI apparatus 100 is turned off by stopping the current supply to the control terminal 11a after the operator performs an operation to turn off the power supply of the MRI apparatus 100. Is transmitted to the cooling water distributor 11.

  While the current is supplied from the computer system 9 to the control terminal 11a, the cooling water distributor 11 distributes the cooling water to each device that needs to be cooled. Further, the cooling water distributor 11 stops the distribution of the cooling water to the equipment that needs to be cooled only when the MRI apparatus 100 is operating when the computer system 9 stops supplying current.

  For example, as shown in FIG. 2, the cooling water distributor 11 includes couplers 11b to 11k, valves 11l to 11u, a first electromagnetic valve 11v, a second electromagnetic valve 11w, and a flow rate adjustment valve 11x. And in the cooling water distribution part 11, the several flow path which distribute | circulates cooling water is provided so that it may demonstrate below.

  First, the cooling water sent from the cooling water supply device 12 flows into the cooling water distributor 11 through the coupler 11b and is sent to the valve 11l. The cooling water that has passed through the valve 11l is sent to the valve 11m, the first electromagnetic valve 11v, and the second electromagnetic valve 11w. The cooling water that has passed through the valve 11m is sent to the refrigerator 10 through the coupler 11c.

  The cooling water that has passed through the first electromagnetic valve 11v is sent to the valves 11n, 11o, and 11p, respectively. The cooling water that has passed through the valve 11n is sent to the gradient coil 2 through the coupler 11d. The cooling water that has passed through the valve 11o is sent to the gradient magnetic field power source 5 through the coupler 11e. The cooling water that has passed through the valve 11p is sent to the transmitter 6 via the coupler 11f. The cooling water that has passed through the second electromagnetic valve 11w is sent to the valve 11u through the flow rate adjustment valve 11x.

  On the other hand, the cooling water sent from the refrigerator 10 flows into the cooling water distributor 11 via the coupler 11g and is sent to the valve 11q. The cooling water sent from the gradient coil 2 flows into the cooling water distributor 11 via the coupler 11h and is sent to the valve 11r. The cooling water sent from the gradient magnetic field power supply 5 flows into the cooling water distributor 11 through the coupler 11i and is sent to the valve 11s. The cooling water sent from the transmitter 6 flows into the cooling water distributor 11 via the coupler 11j and is sent to the valve 11t.

  The cooling water that has passed through each of the valves 11q, 11r, 11s, and 11t is sent to the valve 11u. The cooling water that has passed through the valve 11u is sent to the cooling water supply device 12 through the coupler 11k.

  Here, the valve 11 l adjusts the flow rate of the cooling water sent from the cooling water supply device 12. The valve 11m adjusts the flow rate of the cooling water sent to the refrigerator 10. The valve 11 n adjusts the flow rate of the cooling water sent to the gradient coil 2. The valve 11 o adjusts the flow rate of the cooling water sent to the gradient magnetic field power supply 5. The valve 11p adjusts the flow rate of the cooling water sent to the transmission unit 6.

  The valve 11q adjusts the flow rate of the cooling water sent from the refrigerator 10. The valve 11r adjusts the flow rate of the cooling water sent from the gradient coil 2. The valve 11 s adjusts the flow rate of the cooling water sent from the gradient magnetic field power supply 5. The valve 11 t adjusts the flow rate of the cooling water sent from the transmission unit 6. The valve 11 u adjusts the flow rate of the cooling water sent to the cooling water supply device 12.

  The first electromagnetic valve 11v opens the flow path when current is supplied from the computer system 9, and closes the dew when the current supply from the computer system 9 is stopped. On the other hand, the second electromagnetic valve 11w, contrary to the first electromagnetic valve 11v, closes the flow path when current is supplied from the computer system 9, and opens the dew when the current supply from the computer system 9 is stopped. .

  That is, when current is supplied from the computer system 9, the first electromagnetic valve 11v opens the flow path, and the second electromagnetic valve 11w closes the flow path. As a result, as shown in FIG. 3, cooling water is distributed to the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6. On the other hand, when the current supply from the computer system 9 is stopped, the first electromagnetic valve 11v closes the flow path, and the second electromagnetic valve 11w opens the flow path. As a result, as shown in FIG. 4, the cooling water is distributed only to the refrigerator 10, and the cooling water is not distributed to the gradient coil 2, the gradient magnetic field power supply 5, and the transmission unit 6.

  That is, the first electromagnetic valve 11v and the second electromagnetic valve 11w are respectively connected to the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power source 5, and the transmission unit 6 while the current is supplied from the computer system 9 to the control terminal 11a. Operates to distribute cooling water. Further, the first electromagnetic valve 11v and the second electromagnetic valve 11w stop the distribution of the cooling water to the gradient coil 2, the gradient magnetic field power source 5 and the transmission unit 6 when no current is supplied from the computer system 9. Works like this.

  The flow rate adjusting valve 11x keeps the flow rate of the cooling water supplied to the refrigerator 10 approximately constant before and after the cooling water supply to the gradient magnetic field coil 2, the gradient magnetic field power source 5 and the transmission unit 6 is stopped. The flow rate of the cooling water distributed to the refrigerator 10 is adjusted so that the In other words, the flow rate of the cooling water flowing through the flow rate adjusting valve 11x is the same as that of the gradient magnetic field coil 2, the gradient magnetic field power source 5 and the transmission before the distribution of the cooling water to the gradient magnetic field coil 2, the gradient magnetic field power source 5 and the transmission unit 6 is stopped. It is adjusted in advance so as to be the same as the total flow rate of the cooling water sent to each of the sections 6.

  As described above, the flow rate adjusting valve 11x adjusts the flow rate of the cooling water supplied to the refrigerator 10 to prevent the cooling water from being sent to the refrigerator 10 excessively. Thereby, the phenomenon in which the inner wall of the piping provided between the cooling water distribution part 11 and the refrigerator 10 and the inner wall of the cooling pipe provided in the refrigerator 10 are scraped off by the cooling water can be prevented. Thus, the phenomenon in which the inner wall of the pipe is scraped off is called erosion.

  Although not shown in FIG. 2, a pressure gauge that can measure the pressure of the cooling water and a thermometer that can measure the temperature of the cooling water are provided in the flow path through which the cooling water flows in the cooling water distributor 11. Is preferably provided.

  Next, the operation procedure of the cooling water distributor 11 according to the first embodiment will be described. FIG. 5 is a flowchart illustrating the operation procedure of the cooling water distributor 11 according to the first embodiment.

  As shown in FIG. 5, in the cooling water distributor 11, when the power of the MRI apparatus 100 is turned on (Yes in Step S10), the first electromagnetic valve 11v opens the flow path (Step S11). ). Thereafter, the second electromagnetic valve 11w closes the flow path (step S12). Thereby, the cooling water distribution unit 11 distributes the cooling water to each of the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power source 5, and the transmission unit 6 (step S13).

  On the other hand, when the power supply of the MRI apparatus 100 is turned off (No at Step S10), the second electromagnetic valve 11v opens the flow path (Step S14). Thereafter, the first electromagnetic valve 11w closes the flow path (step S15). Thereby, the cooling water distribution part 11 stops distribution of the cooling water to the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission part 6 (step S16).

  As described above, in the first embodiment, the cooling water distribution unit 11 cools the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 while the power of the MRI apparatus 100 is on. Distribute water. The cooling water distribution unit 11 distributes the cooling water to the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 when the power of the MRI apparatus 100 is changed from on to off. To stop.

  That is, in the first embodiment, while the MRI apparatus 100 is not operating, the cooling water is circulated only in the refrigerator 10 and the operation is stopped in the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6. No cooling water is circulated. For this reason, it is possible to prevent condensation that occurs in the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 while the MRI apparatus 100 is not operating. For this reason, it is not necessary to operate the air conditioning equipment or the dew condensation prevention system while the MRI apparatus 100 is not operating. Therefore, according to the first embodiment, it is possible to prevent dew condensation that occurs in the device while suppressing the amount of power consumed while the MRI apparatus 100 is not operating.

  In the first embodiment, the flow rate adjustment valve 11x adjusts the flow rate of the cooling water distributed to the refrigerator 10. Therefore, since it is possible to prevent the cooling water from being excessively sent to the refrigerator 10, the inner wall of the pipe provided between the cooling water distributor 11 and the refrigerator 10, and the cooling pipe provided in the refrigerator 10 It is possible to prevent erosion from occurring on the inner wall.

  In the first embodiment, the computer system 9 transmits the power state of the MRI apparatus 100 to the cooling water distributor 11. In addition, the insulating transformer 13 insulates the cooling water distributor 11 from the computer system 9. Therefore, according to the first embodiment, it is possible to protect the computer system 9 even when a leakage occurs in the cooling water distributor 11 due to water leakage or the like. In addition, although the case where the insulation transformer 13 was used was demonstrated in the present Example 1, the insulation means for insulating the cooling water distribution part 11 and the computer system 9 is not restricted to this. For example, the cooling water distributor 11 and the computer system 9 may be connected via an optical transmission element.

  In the first embodiment, the case where two electromagnetic valves are used as means for controlling the distribution of the cooling water to the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power source 5 and the transmission unit 6 has been described. However, the present invention is not limited to this. For example, a three-way valve may be used instead of the two solenoid valves. The three-way valve here has one water inlet and two water outlets, and the flow path is switched so that water flowing in from the water inlet flows out from either one of the two water outlets. It is a possible valve.

  Hereinafter, a case where a three-way valve is used will be described as a second embodiment. In addition, the configuration of the MRI apparatus according to the second embodiment is the same as that shown in FIG. 1, and only the configuration of the cooling water distribution unit is different. Therefore, in the second embodiment, the configuration and operation procedure of the cooling water distributor will be described.

  First, the configuration of the cooling water distributor according to the second embodiment will be described. FIG. 6 is a block diagram illustrating the configuration of the cooling water distributor 21 according to the second embodiment. 7 and 8 are diagrams for explaining the flow path switching in the cooling water distributor 21 according to the second embodiment. Here, for convenience of explanation, devices that play the same roles as the devices shown in FIG.

  The cooling water distribution unit 21 according to the second embodiment is similar to the cooling water distribution unit 11 described in the first embodiment, while the current is supplied from the computer system 9 to the control terminal 11a. Distribute cooling water to the equipment. In addition, when no current is supplied from the computer system 9, the cooling water distribution unit 21 stops the distribution of the cooling water to devices that need to be cooled only while the MRI apparatus 100 is operating.

  For example, as shown in FIG. 6, the cooling water distributor 21 includes couplers 11b to 11k, valves 11l to 11u, a three-way valve 21y, and a flow rate adjusting valve 11x. And in the cooling water distribution part 21, the several flow path which distribute | circulates cooling water is provided so that it may demonstrate below.

  First, the cooling water sent from the cooling water supply device 12 flows into the cooling water distributor 21 via the coupler 11b and is sent to the valve 11l. The cooling water that has passed through the valve 11l is sent to each of the water inlets of the valve 11m and the three-way valve 21y. The cooling water that has passed through the valve 11m is sent to the refrigerator 10 through the coupler 11c.

  The cooling water flowing out from one water outlet of the three-way valve 21y is sent to each of the valves 11n, 11o, and 11p. The cooling water that has passed through the valve 11n is sent to the gradient coil 2 through the coupler 11d. The cooling water that has passed through the valve 11o is sent to the gradient magnetic field power source 5 through the coupler 11e. The cooling water that has passed through the valve 11p is sent to the transmitter 6 via the coupler 11f. The cooling water flowing out from the other water outlet of the three-way valve 21y is sent to the valve 11u through the flow rate adjusting valve 11x.

  On the other hand, the cooling water sent from the refrigerator 10 flows into the cooling water distributor 21 via the coupler 11g and is sent to the valve 11q. The cooling water sent from the gradient coil 2 flows into the cooling water distributor 21 via the coupler 11h and is sent to the valve 11r. The cooling water sent from the gradient magnetic field power supply 5 flows into the cooling water distributor 21 via the coupler 11i and is sent to the valve 11s. The cooling water sent from the transmission unit 6 flows into the cooling water distribution unit 21 via the coupler 11j and is sent to the valve 11t.

  The cooling water that has passed through each of the valves 11q, 11r, 11s, and 11t is sent to the valve 11u. The cooling water that has passed through the valve 11u is sent to the cooling water supply device 12 through the coupler 11k.

  When the current is supplied from the computer system 9, the three-way valve 21y switches the flow path so that the cooling water flowing in from the water inlet flows into the valves 11n, 11o, and 11p. As a result, as shown in FIG. 7, cooling water is distributed to the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6. On the other hand, when the current is supplied from the computer system 9, the three-way valve 21y switches the flow path so that the cooling water flowing in from the water inlet flows into the flow rate adjusting valve 11x. As a result, as shown in FIG. 8, the cooling water is distributed only to the refrigerator 10, and the cooling water is not distributed to the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6.

  That is, the three-way valve 21y distributes cooling water to each of the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power source 5, and the transmission unit 6 while a current is supplied from the computer system 9 to the control terminal 11a. Operate. Further, the three-way valve 21 y operates to stop the distribution of the cooling water to the gradient coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 when no current is supplied from the computer system 9.

  Next, an operation procedure of the cooling water distributor 21 according to the second embodiment will be described. FIG. 9 is a flowchart illustrating the operation procedure of the cooling water distributor 21 according to the second embodiment.

  As shown in FIG. 9, in the cooling water distributor 21, when the power of the MRI apparatus 100 is turned on (Yes in step S20), the three-way valve 21y includes the gradient magnetic field coil 2, the gradient magnetic field power supply. 5 and the flow path are switched so that the cooling water flows to the valve side leading to the transmission unit 6 (step S21). Thereby, the cooling water distribution part 21 distributes cooling water to each of the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission part 6 (step S22).

  On the other hand, when the power of the MRI apparatus 100 is turned off (No at Step S20), the three-way valve 21y switches the flow path so that the cooling water flows to the flow rate adjusting valve 11x side (Step S23). . Thereby, the cooling water distribution unit 21 stops the distribution of the cooling water to the gradient magnetic field coil 2, the gradient magnetic field power source 5, and the transmission unit 6 (step S24).

  As described above, in the second embodiment, the cooling water distribution unit 21 cools the refrigerator 10, the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 while the power of the MRI apparatus 100 is on. Distribute water. The cooling water distribution unit 11 distributes the cooling water to the gradient magnetic field coil 2, the gradient magnetic field power supply 5, and the transmission unit 6 when the power of the MRI apparatus 100 is changed from on to off. To stop.

  Therefore, according to the second embodiment, as in the first embodiment, it is possible to prevent condensation that occurs in the gradient magnetic field coil 2, the gradient magnetic field power source 5, and the transmission unit 6 while the MRI apparatus 100 is not operating. For this reason, it is not necessary to operate the air conditioning equipment or the dew condensation prevention system while the MRI apparatus 100 is not operating. Therefore, according to the second embodiment, it is possible to prevent dew condensation that occurs in the device while suppressing the amount of power consumed while the MRI apparatus 100 is not operating. Furthermore, the flow path can be switched more reliably by using a three-way valve.

DESCRIPTION OF SYMBOLS 100 MRI apparatus 1 Static magnetic field magnet 2 Gradient magnetic field coil 3 High frequency coil 4 Top plate 5 Gradient magnetic field power supply 6 Transmitting part 7 Receiving part 8 Sequence control apparatus 9 Computer system 10 Refrigerator 11 Cooling water distribution part 11v 1st solenoid valve 11w 2nd Solenoid valve 11x Flow control valve 12 Cooling water supply device 13 Insulation transformer

Claims (3)

A first device that requires constant cooling;
A second device that only needs to be cooled while the device is in operation;
Refrigerant distribution means for distributing the refrigerant supplied by the refrigerant supply means to the first device and the second device;
The refrigerant distribution means distributes the refrigerant to each of the first device and the second device while the power of the apparatus is on, and the second device when the power is changed from on to off. The magnetic resonance imaging apparatus is characterized in that the distribution of the refrigerant is stopped.   The refrigerant distribution means is provided in the first device so that the flow rate of the refrigerant distributed to the first device is maintained approximately constant before and after the distribution of the refrigerant to the second device is stopped. The magnetic resonance imaging apparatus according to claim 1, further comprising a flow rate adjusting unit that adjusts a flow rate of the refrigerant to be distributed. Control means for transmitting the state of the power source to the refrigerant distribution means;
The magnetic resonance imaging according to claim 1, further comprising: an insulating unit that is inserted between the refrigerant distribution unit and the control unit and insulates the refrigerant distribution unit and the control unit. apparatus.

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