JP2007163513A - Control rod drive, testing method and device of control rod drive, inspection device of control rod drive, storage method and apparatus of control rod drive, and torque transport unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability in a magnetic joint for transferring a drive torque without any contact in a control rod drive. <P>SOLUTION: In the magnetic joint comprising a first joint element 31 and a second one 32 incorporating a plurality of magnets each, sleeves, namely coverings 57, 58, are provided to cover each magnet in each joint element watertightly or airtightly. A sleeve, namely a covering 59, is provided further to cover at least one portion of each magnet inside the coverings watertightly or airtightly. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control rod drive device, a test method thereof, a test device thereof, an inspection device thereof, a storage method thereof, a storage device thereof, and a torque transmission device.

  The control rod drive mechanism is integrated with the control rod and controls the reactivity of the nuclear reactor, and is particularly important for plant operation and safety. FIG. 7 shows a conventional electric control rod drive mechanism.

  FIG. 7 is a longitudinal sectional view showing an electric control rod drive mechanism (CRD) that is provided at the lower part of the reactor pressure vessel of the boiling water reactor (BWR) and drives the control rod (CR) up and down. The control rod drive mechanism includes a motor assembly at the lower end, and a vertical rotating shaft 1 of the motor assembly is connected to an upper vertical drive shaft 3 via a gear coupling 2. A ball screw 4 is connected to the drive shaft 3 so as to be integrally rotatable, and a ball nut 5 is screwed to the ball screw 4 so as to be driven up and down by the rotation of the ball screw 4.

  The outer periphery of the ball nut 5 is provided with a pair of upper and lower rollers 6, and these rollers 6 are attached so as to sandwich an axial mounting plate 8 formed on the inner peripheral surface of the guide tube 7. ing. A hollow piston 9 that surrounds the ball screw 4 and extends upward is provided at an upper portion of the ball nut 5, and a control rod 11 is connected to the upper end of the hollow piston 9 via a coupling 10.

  An outer tube 13 is installed in the CRD housing 12, and the CRD housing 12, the outer tube 13, and the spool piece 14 are fastened with bolts 15.

  A spring 16 is provided at the lower part of the ball screw 4. When the ball nut 5 is moved downward beyond the full pulling position of the control rod, the ball nut 5 compresses the spring 16. In this specification, the state in which the ball nut 5 is compressing the spring 16 is referred to as a “mechanical lower limit state”.

  In addition, a buffer 17 is provided on the upper portion of the outer tube 13, and when the ball nut 5 is moved upward beyond the fully inserted state of the control rod, the buffer 17 is compressed by the hollow piston 9 installed on the upper portion of the ball nut 5. In this specification, the state in which the hollow piston 9 compresses the buffer 17 is referred to as a “mechanical upper limit state”.

  The electric motor assembly includes an electric motor 18, an electromagnetic brake 19, and a position detection device 20. The electric motor 18 drives the control rod, the electromagnetic brake 19 holds the control rod position, and the position detection device 20 checks the control rod position. In an electric control rod drive mechanism in an existing improved boiling water reactor (ABWR), a step motor is employed as the motor 18 and an inverter power source is used as the motor power source 21.

  The motor assembly is connected to the spool piece 14 via a motor bracket 22.

  In the spool piece 14, a gland packing 23 is used in the penetrating portion of the drive shaft 3. In the spool piece 14, a coil spring 24 and a magnet housing 26 that is supported by the coil spring 24 and that incorporates a separation detection magnet 25 are installed. When the load applied to the coil spring 24 is reduced, such as when the hollow piston 9 is separated from the ball nut 5, the coil spring 24 is extended, and the separation detection magnet 25 is moved upward accordingly. A separation detection probe 27 having a built-in reed switch operated by magnetism is installed outside the spool piece 14 so that the movement of the separation detection magnet 25 can be detected.

  A scram position detection magnet 28 is built in the hollow piston 9. A full-in detection magnet 29 that moves with the compression of the buffer 17 during scrum is installed in the guide tube 7. A scrum position detection probe 30 incorporating a reed switch that is operated by magnetism is provided outside the control rod drive mechanism housing 12 so that the movement of the scrum position detection magnet 28 and the full-in detection magnet 29 can be detected.

  In the control rod drive mechanism configured as described above, when the electric motor 18 is rotationally driven, the ball screw 4 is rotated via the rotary shaft 1 and the drive shaft 3, and the ball nut 5 is moved up and down by the rotation of the ball screw 4. Move. At this time, the ball nut 5 moves up and down with its rotation restricted by the mounting plate 7 via the roller 6. The hollow piston 9 and the control rod 11 move up and down in conjunction with the vertical movement of the ball nut 5, and the vertical movement of the control rod 11 adjusts the amount of insertion and extraction into the core and controls the furnace output.

  During scram, the hollow piston 9 coupled to the control rod 11 via the coupling 10 is rapidly pushed up by the water pressure supplied from the water pressure control unit and separated from the ball nut 5, and the control rod 11 is rapidly inserted into the core. . At this time, the separation of the hollow piston 9 from the ball nut 5 is detected by the separation detection probe 27. Further, the position of the control rod 11 during and after the scrum is detected by the scrum position detection probe 30.

  Further, in the control rod friction measurement test to be performed at the regular inspection, the control rod friction measurement test device is connected to the water pressure control unit, and the control rod drive device is supplied with water pressure through the test device, thereby controlling the control rod. Is inserted into the core. The operation of the control rod drive mechanism at this time is the same as the operation during scrum except that the insertion speed is low. In the control rod friction measurement test, the friction state between the control rod and surrounding equipment is confirmed by measuring the fluctuation of the water pressure at the time of insertion.

The control rod drive mechanism described above has a gland packing 23 as the shaft seal portion of the spool piece 14 and employs a step motor using an inverter power source as the electric motor 18. ) Improvements such as the removal of the spool piece shaft seal by adopting a magnetic coupling (magnet coupling), and (2) change of the motor type (induction motor), etc. have been studied. For example, JP-A-10-132997 And JP-A-10-274688.
JP-A-10-132997 JP-A-10-274688

  However, the control rod drive mechanism described above has room for establishment or improvement of technology in the following points.

  As shown in FIG. 7, the conventional electric control rod drive mechanism employs a step motor as the electric motor and employs an inverter power source as the electric motor power source, but the system is complicated and the amount of power supply is large. In view of this, the control rod drive mechanism employing an induction motor, which is currently under investigation, has been required to simplify the power supply system. Accordingly, studies on the application of induction motors have been made in recent years, but a power supply device, a control device, a means for confirming soundness of drive performance, etc. when an induction motor is applied have not been established.

  Further, in the control rod drive mechanism employing a magnetic coupling, the structure and specifications of the magnetic coupling itself have been studied, but the maintenance and testing means have not been established. Also, in the unlikely event that the magnetic coupling part steps out, the actual position of the control rod may be unclear. For this reason, several means for solving this problem have been proposed in recent years, but the system is complicated and impractical, and there is a need to establish rational detection means.

  Moreover, when using the magnetic coupling part in water, if the jacket covering the magnetic coupling is damaged, the built-in magnet and water may come into contact with each other, and the magnetic coupling performance may deteriorate due to rusting or the like. For this reason, establishment of a means for ensuring the function of the magnetic coupling is desired even when the above-described event occurs.

  In addition, in the conventional control rod friction measurement test, it is necessary to carry out the control rod friction measurement test device to each hydraulic pressure control unit while sequentially connecting them on site, and the impact on the process is great. Since this is a work in a controlled area, establishment of a simpler test method is desired from the viewpoint of improving workability and reducing exposure.

  The present invention has been made in view of the above-described circumstances. A control rod drive mechanism and a reliable control rod drive mechanism are established while establishing related systems such as a control rod drive mechanism and a power supply device and a control device, and establishing test means. The purpose is to provide.

  In order to achieve the above object, the present invention provides the invention described in the claims.

  The invention according to claim 1 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In a test apparatus for a control rod drive device having a drive mechanism that is transmitted to a control rod through a magnetic coupling to raise and lower the control rod, the electric motor constituting the magnetic coupling in a state where the spool piece is attached to the drive mechanism A torque applying means capable of applying a torque to the joint element on the assembly side or a shaft connected to the joint element, and a torque measuring means for measuring the applied torque are provided.

  According to a second aspect of the present invention, an electric motor assembly including an electric motor, a spool piece, a magnetic coupling having a pair of coupling elements separated by the spool piece, and a rotational motion generated by the electric motor are converted into a linear motion. A control rod drive having a ball nut and a ball screw, and having a drive mechanism for raising and lowering the control rod by transmitting the driving force generated by the electric motor to the control rod via the magnetic coupling, the ball nut and the ball screw In the method of testing an apparatus, the position of a ball nut constituting the ball screw is set to a mechanical minimum limit state or a mechanical maximum limit state in a state where the spool piece is attached to the drive mechanism, and the magnetic coupling is configured. Apply torque to the coupling element on the motor assembly side or the shaft connected to the coupling element to It is characterized by determining the presence or absence of the magnetic coupling abnormality.

  The invention according to claim 3 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In a test apparatus for a control rod drive device provided with a drive mechanism that transmits the control rod to a control rod via a magnetic coupling and moves the control rod up and down, the magnetic coupling is configured with the spool piece attached to the drive mechanism. Torque application means capable of applying torque to the joint element on the motor assembly side or the shaft connected to the joint element, and a torque limiter for limiting the torque applied by the torque application means. It is a feature.

  The invention according to claim 4 converts an electric motor assembly including an electric motor, a spool piece, a magnetic coupling having a pair of coupling elements separated by the spool piece, and a rotational motion generated by the electric motor into a linear motion. A test method for a control rod drive device having a ball screw and a drive mechanism for transmitting and lowering the control rod by transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling and the ball screw In the state where the spool piece is attached to the drive mechanism, the position of the ball nut is set to the mechanical lower limit state or the mechanical upper limit state, and the motor assembly side joint element or the joint constituting the magnetic joint is formed. Torque is applied to the shaft connected to the element via a torque limiter set to a predetermined limit value, and the magnetic coupling is applied. It is characterized by determining the presence or absence of abnormality.

  According to a fifth aspect of the present invention, in the first or third aspect of the invention, the coupling element on the motor assembly side or the coupling element constituting the magnetic coupling in a state where the spool piece is attached to the drive mechanism. And a rotation angle measuring means for measuring a rotation angle of the joint element on the motor assembly side or the shaft connected to the joint element, which is connectable to a shaft connected to the joint element.

  According to a sixth aspect of the present invention, in the second or fourth aspect of the invention, when applying torque to the joint element on the motor assembly side or the shaft connected to the joint element, the motor assembly side The rotation angle of the joint element or the shaft connected to the joint element is measured in association with the torque value, and the presence or absence of abnormality of the magnetic coupling is determined based on the measurement result.

  The invention according to claim 7 is the joint element on the motor assembly side or the joint element in a state where the motor assembly is detached from the drive mechanism in the invention according to any one of claims 2, 4 and 6. Torque is applied to the shaft connected to the.

  According to an eighth aspect of the present invention, in the invention according to any one of the second, fourth, and sixth aspects, the electric motor assembly is mounted from a lower part of the electric motor assembly in a state where the electric motor assembly is attached to the drive mechanism. A shaft is rotated, and torque is applied to a joint element on the motor assembly side or a shaft connected to the joint element via the shaft of the motor assembly.

  According to the first to eighth aspects of the present invention, it is possible to confirm the soundness of the magnetic coupling by measuring the transmission torque, the rotation angle, and the like while the spool piece having the magnetic coupling is attached to the drive mechanism. In addition, the installation of the torque limiter can prevent the magnetic coupling from stepping out due to excessive torque application. Also, the set value of the torque limiter is used as a judgment value for confirming the soundness of the magnetic joint, and the soundness of the magnetic joint can be confirmed by applying the torque up to the set value of the torque limiter and confirming the presence or absence of the step-out. According to the first to eighth aspects of the present invention, it is possible to check the soundness of the magnetic joint while the spool piece is attached to the drive mechanism, and it is not necessary to remove the spool piece for the purpose of checking the soundness of the magnetic joint. It is possible to reduce the amount of work, the process, and the amount of exposure at the time of plant regular inspection.

  The invention according to claim 9 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is A control device for a control rod drive device having a drive mechanism that transmits and moves the control rod to and from the control rod via a magnetic coupling, wherein the control that constitutes the magnetic coupling in the test device that tests the spool piece A rotation restraining means that is connectable to a joint element on the rod side or a shaft connected to the joint element, and restrains the rotation of the joint element on the control rod side or the shaft connected to the joint element; It is connectable to a joint element on the motor assembly side to be configured or a shaft connected to the joint element, and the joint element on the motor assembly side or the joint Torque applying means for applying a torque to the connected axis-containing, further comprising a are characterized.

  The invention according to claim 10 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is And a drive mechanism for moving the control rod up and down by transmitting it to the control rod via a magnetic coupling, wherein the magnetic coupling is configured in the test device for testing the spool piece. A torque applying means that is connectable to a joint element on the control rod side or a shaft connected to the joint element, and that applies torque to the joint element on the control rod side or the shaft connected to the joint element; and the magnetic coupling The motor assembly side joint element or a shaft connected to the joint element, and the motor assembly side joint element or It is characterized by comprising a rotation restraining means for restraining rotation of the connected shafts in the coupling element.

  The invention according to claim 11 is the invention according to claim 9 or 10, wherein the joint element on the control rod side or the shaft connected to the joint element, or the joint element on the motor assembly side or the joint element is provided. A torque limiter that is connectable to one of the connected shafts and limits the torque applied by the torque applying means is further provided.

  According to a twelfth aspect of the present invention, in the invention according to the ninth or tenth aspect, the joint element on the control rod side or a shaft connected to the joint element, or the joint element on the motor assembly side or the joint element is provided. The rotation angle of the joint element on the control rod side or the shaft connected to the joint element or the joint element on the motor assembly side or the axis connected to the joint element can be connected to one of the connected shafts. A rotation angle measuring means for measuring is further provided.

  According to the ninth to twelfth aspects, when the spool piece is removed, the soundness of the magnetic coupling portion can be confirmed by measuring the transmission torque of the magnetic coupling portion. When removing the spool piece, the soundness of the magnetic coupling portion is confirmed based on the inventions of claims 9 to 12, and compared with the method based on the inventions of claims 1 to 8, the working environment outside the containment vessel is reduced. Tests can be conducted in good locations, improving workability and reducing exposure.

  The invention according to claim 13 is the invention according to claim 9 or 10, further comprising pressure supply means for pressurizing the inside of the spool piece, and pressure measuring means for measuring the pressure inside the spool piece. It is characterized by that.

  According to the thirteenth aspect of the present invention, when the spool piece is removed, the pressure resistance test can be performed by pressurizing the inner side of the spool piece partition wall.

  The invention according to claim 14 has an electric motor assembly including an electric motor and a spool piece incorporating a magnetic coupling, and transmits the driving force generated by the electric motor to the control rod via the magnetic coupling to raise and lower the control rod. A storage device for a control rod drive device having a drive mechanism for storing a spool piece, wherein the storage device stores the spool piece, and has a magnetic outer cover covering a part or all of the spool piece.

  The invention according to claim 15 has an electric motor assembly including an electric motor and a spool piece incorporating a magnetic coupling, and transmits the driving force generated by the electric motor to the control rod via the magnetic coupling to raise and lower the control rod. A storage device for a control rod drive device having a drive mechanism for storing a magnetic coupling, wherein the storage device stores the magnetic coupling, and has a magnetic covering that covers part or all of the magnetic coupling.

  According to the fourteenth and fifteenth aspects of the present invention, the magnetic field leaking from the magnetic coupling or the like is confined by the outer shell of the magnetic body during storage or inspection of the spool piece having the magnetic coupling, or during storage or inspection of the magnetic coupling. It is possible to reduce the magnetic influence on the surrounding equipment.

  The invention according to claim 16 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In an inspection device for a control rod drive device having a drive mechanism that transmits to a control rod via a magnetic coupling to raise and lower the control rod, one coupling element constituting the magnetic coupling or a shaft connected to the coupling element First radial position fixing means for fixing the position in the radial direction, and a second radial position for fixing the position of the other coupling element constituting the magnetic coupling or the shaft connected to the coupling element in the radial direction Fixing means, and disassembling or assembling the spool piece in a state where the axis of the spool piece and each joint element is fixed. It is.

  In the sixteenth aspect of the present invention, it is preferable that the magnetic coupling is further provided to cover part or all of the magnetic coupling.

  Since the magnetic coupling contains a strong magnet, when disassembling / assembling with the axis line not fixed, the magnetic coupling is spooled by the attractive force of the inner and outer magnetic couplings or the magnetic coupling and the surrounding magnetic material. There is a possibility of causing damage to the magnetic joint in the piece partition. Therefore, according to the invention described in claim 24, by disassembling / assembling the inner magnetic coupling and the outer magnetic coupling with the axis fixed, it is possible to prevent the equipment from being damaged and to safely perform the disassembling / assembling work. It becomes.

  The invention according to claim 17 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In a storage method of a control rod drive device including a drive mechanism that transmits to a control rod via a magnetic coupling and raises and lowers the control rod, a part or all of the magnetic coupling joint is covered and stored with a nonmagnetic covering. It is characterized by that.

  When the magnetic coupling is removed from the spool piece, attached, and stored, there is a possibility that surrounding magnetic materials and the like may adhere to the magnetic coupling due to the magnetic field of the magnetic coupling. Therefore, according to the invention of claim 17, it is possible to prevent the magnetic body from adhering to the surface of the magnetic coupling by covering the periphery of the magnetic coupling with the non-magnetic body.

  The invention according to claim 18 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In a storage method of a control rod drive device having a drive mechanism that transmits to a control rod via a magnetic coupling to raise and lower the control rod, a part or all of the magnetic coupling is covered and stored with a jacket of a magnetic body. It is a feature.

  According to the eighteenth aspect of the present invention, it is possible to confine the magnetic field leaking from the magnetic coupling or the like with the outer jacket of the magnetic body when storing the spool piece having the magnetic coupling, and to reduce the magnetic influence on the surrounding equipment. is there.

  The invention according to claim 19 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In an inspection device for a control rod drive device provided with a drive mechanism for moving the control rod up and down by transmitting it to the control rod via a magnetic coupling, the water tank for disassembling and assembling the spool piece, and the permanent magnet or induction magnet And means for collecting the magnetic material in the water tank.

  According to the nineteenth aspect of the present invention, the amount of magnetic material adhering to the magnetic coupling is reduced by collecting the magnetic powder and the like in the water tank from which the magnetic coupling is removed and attached from the spool piece with the permanent magnet or the induction magnet. It becomes possible to do.

  The invention according to claim 20 includes an electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and the driving force generated by the electric motor is In an inspection method of a control rod drive device having a drive mechanism that transmits to a control rod via a magnetic coupling to raise and lower the control rod, pressurized fluid is sprayed on the magnetic coupling before or after the inspection, and the coupling element It is characterized by removing foreign matter on the surface of the surface.

  According to the twentieth aspect of the present invention, it is possible to remove foreign matters such as a magnetic body adhering to the surface of the magnetic coupling by ejecting the pressurized fluid.

  The invention according to claim 21 includes a first joint element containing a plurality of magnets and connected to a first shaft, and a second joint containing a plurality of magnets and connected to a second shaft. A first joint that covers all the magnets of the first joint element in a watertight or airtight manner and all the magnets of the second joint element in a watertight or A third outer cover that covers a part of or all of the magnet built in the first joint element inside the first outer cover in a water-tight or air-tight manner. At least one of a jacket and a fourth jacket covering a part or all of the magnet built in the second joint element inside the second jacket in a watertight or airtight manner. It is characterized by that.

  In an underwater environment or the like, a structure in which the surface of the magnetic coupling is covered with a jacket is used in order to prevent the magnetic properties from being changed due to contact between the magnet and water. By installing a magnet covered with a jacket inside the jacket that covers the surface of the magnetic coupling, even if the jacket covering the inner / outer magnetic coupling surface is damaged, contact between the magnet and water is prevented. It is possible to ensure the soundness of the magnet. This improves the reliability of the magnetic coupling.

  The invention described in claim 22 is a control rod drive device that drives the control rod of a nuclear reactor up and down, and has an electric motor and the torque transmission device according to claim 21, and the driving force generated by the electric motor Is transmitted to the control rod through the torque transmission device, and a drive mechanism for raising and lowering the control rod, and a power supply device for supplying electric power to the electric motor are provided.

  The invention described in claim 23 is a control rod drive device that drives the control rod of a nuclear reactor up and down, and includes an electric motor and a torque transmission device according to claim 21, wherein the driving force generated by the electric motor is A torque transmission device and a drive mechanism that moves the control rod up and down by transmitting to the control rod via the ball screw, the first joint element of the torque transmission device is installed inside the spool piece partition, A second joint element of the torque transmission device is installed, and a magnet covered with a third jacket of the first joint elements functions to cover the third jacket of the first joint element. The torque transmission device has a maximum transmission torque that is equal to or greater than a torque required for holding the control rod position during normal operation of the nuclear reactor in a state in which an unused magnet does not function.

  According to the invention described in claims 22 and 23, since the torque transmission device according to claim 21 is incorporated in the control rod drive mechanism, a highly reliable control rod drive mechanism using a magnetic coupling is constructed. It is possible.

  As described above, according to the present invention, a control rod drive mechanism and a control rod drive mechanism with high reliability can be provided while establishing related systems such as a power supply device and a control device, establishing maintenance, and establishing test means. It becomes possible.

BEST MODE FOR CARRYING OUT THE INVENTION

  Preferred embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
First, the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 schematically shows the lower structure of the control rod drive mechanism according to the first embodiment, that is, the structure of the spool piece portion and the motor assembly portion. The structure above the spool piece 14 is the same as that of the prior art described with reference to FIG. 7, and members constituting the part are denoted by the same reference numerals as those in FIG. To do. Regarding the lower structure, members that are the same as or similar to those described in FIG. 7 are assigned the same reference numerals as in FIG.

  First, the configuration of the control rod drive mechanism according to this embodiment will be described below.

  The control rod drive mechanism shown in FIG. 1 has a magnetic coupling composed of an inner magnetic coupling element 31 and an outer magnetic coupling element 32 separated by a spool piece 14 partition, a separation detection magnet 25, a drive shaft 3, and the like. Yes.

  In the upper structure of the control rod driving mechanism, a ball screw 4, a ball nut 5, a hollow piston 9, a scram position detection magnet 28, a full-in detection magnet 29, and the like are provided.

  An electric motor assembly is provided at the lower part of the spool piece 14, and the outer magnetic coupling 32 on the spool piece 14 side and the rotary shaft 1 on the electric motor assembly side are coupled via a coupling 2.

  The electric motor assembly includes a holding brake 19, a position detection device (synchronized position resolver) 20, a transmission 33, and an induction motor 35 to which a braking brake 34 is attached. The holding brake 19 and the braking brake 34 both have a holding torque at rest of 0.3 kgfm or more as a torque necessary for holding the control rod position during normal operation of the nuclear reactor. is doing.

  In this way, both the holding brake 19 and the braking brake 34 are set to the torque required for holding the control rod position during normal operation, so that one brake function loss should be taken into consideration. Even so, the control rod position can be reliably held, and a highly reliable control rod drive mechanism can be constructed.

  Thermometers 36 and 37 are installed between the outer magnetic coupling element 32 and the partition wall of the spool piece 14 and in the winding portion of the induction motor 35, respectively. The thermometer 36 may be disposed in the vicinity of the outer peripheral surface of the outer magnetic coupling element 32, and the thermometer 37 is disposed in the vicinity of the winding portion of the induction motor 35 or in an appropriate position in the casing. Also good.

  A separation detection probe 27 and a scram position detection probe 30 are provided outside the spool piece 14, and each of the probes 27 and 30 has a reed switch that is operated by magnetism.

  A plurality of reed switches (not shown) of the scram position detection probe 30 are arranged in the vertical direction, and 0, 10, 40, 60, 100% (0% is fully pulled out, 100% is relative to the full stroke of the control rod. It is possible to detect a corresponding position (which means the fully inserted state). The separation detection probe 27 has a separation detection reed switch 38 for detecting the position of the separation detection magnet 25 and a magnetic joint out-of-step detection reed switch 39 for detecting the magnetic field state in the vicinity of the magnetic coupling.

  The induction motor 35 is connected to a motor power supply device 41. For example, a fixed frequency power supply 44 of 60 Hz is connected to the motor power supply device 41. In addition to the fixed frequency power supply 44, a variable frequency power supply 45 is also provided, and either the fixed frequency power supply 44 or the variable frequency power supply 45 can be selectively connected to the motor power supply device 41. The variable frequency power supply 45 may be capable of changing the frequency stepwise, or may be capable of continuously changing the frequency.

  In the induction motor 35, the synchronous rotational speed is proportional to the power supply frequency, and the rotational speed varies depending on the load. In this embodiment, it is possible to select a plurality of frequencies as the electric motor power source, medium speed drive during reactor operation, high speed drive during reactor shutdown, and control performed at plant inspection when reactor shut down In the rod friction measurement test, operation with high flexibility is possible depending on the situation, such as low-speed driving.

  In particular, in the control rod friction measurement test, it is possible to detect load fluctuations such as friction by driving the control rod from the fully pulled out state to the fully inserted state and measuring the driving speed. In a control rod friction measurement test or the like, driving at a low speed can clearly detect even a short-term load fluctuation or the like, and is a highly reliable test. Of course, if it is possible to confirm a short-term load fluctuation or the like without any problem in the medium speed drive as in the reactor operation, it is also possible to carry out the control rod friction measurement test in the medium speed drive.

  In addition, when the load of the induction motor 35 fluctuates, the supply of electrical energy to the induction motor 35 changes, so an ammeter, voltmeter, wattmeter, or the like is installed in the power supply device 41. The control rod friction measurement test can also be performed by confirming the detected value.

  Further, in the present embodiment, a 60 Hz fixed frequency power supply 44 and a variable frequency power supply 45 are provided separately, so that they are connected to the fixed frequency power supply 44 during the operation of the nuclear reactor and variable frequency power supplies as necessary during the reactor shutdown. By operating so as to connect to 45, the possibility of connecting to an incorrect power source during the operation of the reactor is eliminated, and a highly reliable operation is possible.

  In this embodiment, a plurality of types of frequencies can be selected. However, even if a plurality of different types of voltages can be selected, it is possible to drive at different driving speeds. In this case, instead of the fixed frequency power supply 44 and the variable frequency power supply 45, a fixed voltage power supply 44 and a variable voltage power supply 45 may be provided.

  Referring to FIG. 1 again, the electric motor power supply device 41 has two switches 40 connected in series. Each switch 40 can be independently controlled by a signal transmitted from the control device 42 via command signal transmission paths of different systems. Further, a thermal relay 43 is attached to the motor power supply device 41 as a protective relay. When the load torque of the induction motor 35 increases, the drive current value supplied to the induction motor 35 increases and the thermal relay 43 operates. The protective relay is not limited to the thermal relay 43, and other protective relays may be used.

  The holding brake power supply device 46 is also connected to the holding brake 19. A fixed frequency power supply (not shown) is connected to the power supply device 46. The holding brake power supply 46 also has two switches 47 connected in series. Each switch 40 can also be independently controlled by a signal transmitted from the control device 42 via command signal transmission paths of different systems.

  In this way, by installing the two switches 40 and 47 in series with the electric motor power supply 41 and the holding brake power supply 46, respectively, it is possible to prevent erroneous operation of the control rod due to a single failure or the like, and reliability is improved. improves.

  The switches 40 and 47 may be contacts or semiconductor switches.

  Next, the configuration of the magnetic coupling portion will be described in detail with reference to FIG. The inner magnetic coupling element 31 constituting the magnetic coupling incorporates eight-pole magnets 50 and 51, and the outer magnetic coupling element 32 constituting the magnetic coupling similarly incorporates eight-pole magnets 48 and 49. ing. In addition, the magnets 48, 49, 50, 51 have yokes 53, 54, 55, 56 made of a magnetic material for constituting the magnetic circuit 52, respectively.

  The inner surfaces of the magnets 48 and 49 of the outer magnetic coupling element 32 are covered and sealed by the sleeve 57, and the outer surfaces of the magnets 50 and 51 of the inner magnetic coupling element 31 are covered and sealed by the sleeve 57. The inner and outer magnetic coupling elements 31, 32 are magnetically coupled by the magnetic force of each magnet 48, 49, 50, 51. Therefore, power can be transmitted between the inner and outer magnetic coupling elements 31 and 32 in a non-contact manner via the partition wall portion of the spool piece 14.

  As shown in FIG. 2 (a), the magnet 51 (hereinafter referred to as "magnet A") with the symbol A of the outer magnetic coupling element 32 is another magnet 49 (hereinafter referred to as "magnet B") with the symbol B. It is a smaller magnet. Further, the magnet 50 (hereinafter referred to as “magnet C”) denoted by reference numeral C of the inner magnetic coupling element 31 is smaller than the other magnet 51 (hereinafter referred to as “magnet D”) denoted by reference numeral D. .

  In addition, the yoke (hereinafter referred to as “yoke A”) attached with the symbol A in contact with the magnet A of the outer magnetic coupling element 32 is smaller than the yoke attached with the symbol B (hereinafter referred to as “yoke B”). Yes. Also. The yoke attached with reference C (hereinafter referred to as “yoke C”) in contact with the magnet attached with reference C of the inner magnetic coupling element 31 is smaller than the yoke attached with reference D (hereinafter referred to as “yoke D”). It has become. However, the yoke A and the yoke B may be integrally formed, and the yoke C and the yoke D may be integrally formed.

  Moreover, as shown in FIG.2 (b), the small magnet, ie, the magnet A and the magnet C, are individually covered with the outer cover 59, and have the spacer 60 in the upper part. FIG. 2B shows only the magnet C and its surrounding configuration, but the magnet A and its surrounding configuration are also magnets except that the yoke is located on the outer peripheral side of the magnet. The configuration is the same as that of C and its surroundings (see FIG. 2A).

  As shown in FIG. 2 (a), two magnets A and C and two yokes A and C are provided, and are arranged at positions symmetrical with respect to the axis. It arrange | positions so that it may mutually oppose.

  This magnetic coupling does not expect the functions of the magnets B and D, and only the magnetic attraction force acting between the magnets A and C is used as a torque necessary for holding the control rod position during the normal operation of the reactor. The maximum transmission torque of 0.3 kgfm or more is ensured.

  As described above, not only the surfaces of the magnets constituting the magnetic coupling are covered with the sleeves 57 and 58, but also the magnets 48 (magnet A) and the magnet 50 (magnet C) for two poles are individually covered with the jacket 59. The sleeves 57 and 58 are damaged by any reason because they are configured to be able to exhibit the control rod position holding torque during normal operation without expecting the functions of the other magnet 49 (magnet B) and magnet 51 (magnet D). Thus, even when water or the like enters the magnetic coupling and the magnets 49 (magnet B) and 51 (magnet D) lose their functions due to rusting or the like, the magnet 48 (magnet A) and the magnet 50 are more securely protected. Since the function of (magnet C) is not lost, the position of the control rod can be reliably maintained. Therefore, a highly reliable control rod drive mechanism can be constructed.

  In the unlikely event that this magnetic coupling is out of step, it can be detected by the following methods (1) to (2).

  (1) First, the first method will be described. In this magnetic coupling, the small magnet A and the small magnet C face each other between the inner / outer magnetic couplings 31 and 32 in a normal state. However, when the magnetic coupling steps out, the small magnets A and C and the larger magnets B and D face each other. The small magnets A and C are in contact with the small yokes A and C. When the small magnets A and C are opposed to the large magnets B and D, the magnetic lines of force 52 cannot be confined in the yoke, so that Magnetic field lines are released, and the surrounding magnetic field changes. By detecting such a change in the magnetic field state by the magnetic coupling out-of-phase detection reed switch 39 provided in the separation detection probe 27, it is possible to detect the out-of-phase of the magnetic coupling. In the present embodiment, a small magnet is partially incorporated inside the magnetic coupling, but the same effect can be expected when a magnet having different magnetic characteristics (for example, magnetic flux density) is incorporated.

  (2) Next, the second method will be described. When the magnetic coupling is stepped out, the coupling phase between the inner / outer magnetic coupling elements 31, 32 changes, so that the position information is detected from the shaft (rotary shaft 1) connected to the outer magnetic coupling element 32. The relationship between the output of the detection device 20 and the output of the scram position detection probe 30 that detects position information from the hollow piston 9 connected to the inner magnetic coupling element 31 differs from that in the normal state.

  Therefore, the output of the position detection device 20 and the output of the scrum position detection probe 30 are compared, and whether or not the magnetic coupling has stepped out can be confirmed based on whether or not a predetermined relationship is established therebetween.

  When the magnetic coupling out-of-step is detected by the above method, the control device 42 stops the power supply to the electric motor 35 to stop the drive of the control rod, or the output of the position detection device 20 and the scram position. Appropriate measures such as displaying that the output of the detection probe 30 is out of a predetermined relationship or generating an alarm can be made. Furthermore, as a subsequent treatment, it is possible to implement appropriate measures such as isolating the control rod drive mechanism as an inoperable control rod, and a highly reliable control rod drive mechanism can be constructed.

  Next, the operation of the control device 42 will be described. The control device 42 has the following functions.

  (1) The control device 42 issues a control rod drive / stop command based on the operation of the operator. In this case, the power supply devices 41 and 46 controlled by the control device 42 start or stop power supply to the induction motor 35, the control brake 34, and the holding brake 19.

  (2) At the start of driving the control rod, the control device 42 first controls the power supply device 46 and first releases the holding brake 19. Next, the control device 42 controls the power supply device 41 to energize the braking brake 34 and the induction motor 35 simultaneously. Note that when the brake 34 is energized, the brake operation is stopped and the brake is released. Thereby, the rotating shaft 1 starts rotating.

  (3) When stopping the driving of the control rod, the control device 42 first controls the power supply device 41, and first stops energization to the braking brake 34 and the induction motor 35 at the same time. The braking brake 34 performs a holding operation when not energized. Then, after the rotation of the rotating shaft 1 stops, the control device 42 controls the power supply device 46 to place the holding brake 19 in the holding state.

  By shifting the operation timing of the holding brake 19 and the braking brake 34 in this way, wear due to sliding of the holding brake 19 can be reduced, and the service life and reliability of the holding brake 19 can be improved. is there.

  (4) Further, the control device 42 can perform control to issue a drive stop command when the control rod is driven, for example, 4 mm before the stop target position. In other words, considering the transmission delay, the capacity of the brake 35 for braking, and the like, it is considered that the control rod advances and stops by 2 mm or more after the control rod stop command is transmitted from the control device 42. Therefore, by issuing a stop command 4 mm before the stop target position, the accuracy of the stop position is improved. The control device grasps the position of the control rod based on the signal transmitted from the position detection device 20, but also monitors the signals from the separation detection probe 27 and the scram position detection probe 30 together.

  (5) Further, the control device 42 (a) monitors the temperature of the winding portion of the induction motor 35 by monitoring a signal transmitted from the thermometer 37 to the control device 42, and (b) controls from the thermometer 36. The magnetic joint temperature is monitored by monitoring a signal transmitted to the device 42, and (c) and the control rod driving speed is monitored by monitoring a signal transmitted from the position detecting device 20. The control rod driving speed can be calculated by differentiating the control rod position detected by the position detection device 20 with respect to time, or from the amount of change per unit time of the control rod position.

  When these values exceed the first predetermined value, an alarm is generated toward the operator by an alarm generator (not shown). When the first predetermined value is exceeded, instead of generating an alarm or in addition to generating an alarm, information indicating that fact may be displayed by appropriate display means and transmitted to the operator. .

  When the above value is closer to the critical value than the first predetermined value and exceeds the second predetermined value, the control device 42 issues a control rod drive stop command.

  In the above description, the first predetermined value and the second predetermined value are set, and the control device 42 takes a predetermined action when each predetermined value is exceeded. However, the present invention is not limited to this. Instead of setting the permissible values in a predetermined range for the winding temperature of the induction motor 35, the magnetic joint temperature, and the control rod drive speed, and when each parameter deviates from the permissible predetermined range. In the same manner as described above, measures such as stopping the motor and generating an alarm may be taken.

  (6) When the thermal relay 43 is activated, the control device 42 issues an alarm, and further issues a control rod drive stop command. As a result, it is possible not only to quickly detect abnormality of the control rod, but also to prevent an excessive torque from being applied to the magnetic coupling, and to prevent the magnetic coupling from being stepped out.

  Instead of providing the thermal relay 43, the power supply device 41 is provided with an ammeter, voltmeter, or wattmeter, and supplied to the induction motor 35 by monitoring a signal transmitted from the ammeter or the like to the control device 42. The current value (which may be a voltage value or a power value) to be monitored may be monitored, and when the value exceeds the first predetermined value, an alarm may be issued to the operator by an alarm generator (not shown). Further, when the first predetermined value is exceeded, information representing that fact may be displayed by appropriate display means instead of the occurrence of the alarm or in addition to the occurrence of the alarm, and may be transmitted to the operator. . Further, when the above value is closer to the critical value than the first predetermined value and exceeds the second predetermined value, the control device 42 may issue a control rod drive stop command.

  (7) The control device 42 compares the actual stop position after the drive stop of the control rod with the target stop position or the control rod position when the drive stop command is generated, and the actual stop position and the target stop position or the drive stop command. When the difference from the control rod position at the time of occurrence deviates from a predetermined range, the fact that the predetermined range has been deviated is displayed by a display device (not shown) or an alarm is issued to an operator by an alarm generation device (not shown) .

  Alternatively, the control device 42 compares the stop position after stopping the driving of the control rod with the initial position before starting the driving of the control rod, and when the difference between the stopping position and the initial position deviates from a predetermined range, The fact that it deviates from the predetermined range is displayed by a display device (not shown), or an alarm is issued to the operator by an alarm generation device (not shown).

  (8) The control device 42 compares the output of the position detection device 20 with the output of the scram position detection probe 30, and the relationship between the two is a predetermined relationship at the control rod full insertion position, the control rod full extraction position, or other positions. When it is out of the range, an alarm is issued and a control rod drive stop command is issued.

  (9) When the magnetic joint out-of-step detection reed switch 39 is actuated, the control device 42 issues an alarm and issues a control rod drive stop command.

  (10) When the thermal relay is activated, the control device 42 issues an alarm and stops the power supply to the electric motor.

  (11) At the time of control rod insertion operation, the control device 42 can execute a drive mode in which the control rod is once inserted beyond the target stop position and then automatically pulled out to the target stop position.

  As described above, each control performed by the control device 42 ensures the accuracy of the control rod drive, and can generate an alarm based on the state of the control rod drive mechanism or stop the control rod drive. Yes, the reliability of the control rod drive mechanism is improved.

[Second Embodiment]
Next, a second embodiment will be described with reference to FIG. The second embodiment relates to a method and apparatus for inspecting a magnetic coupling that forms part of a control rod drive mechanism.

  FIG. 3 shows a state where the motor assembly is removed from the control rod drive mechanism shown in FIG. In this case, the scram position detection probe 30, the separation detection probe 27, and the like are also removed.

  In the present embodiment, as shown in FIG. 3, the outer magnetic coupling element 32 has an opening 61 at a position corresponding to the pole of each magnet below the outer magnetic coupling element 32. The magnetic sensor 62 can be inserted between the 14 partition walls.

  Next, a first inspection method for the magnetic coupling will be described. First, a first test device having a magnetic sensor 62, a cable 63 connected to the magnetic sensor 62, and a recorder 64 is prepared. When the motor assembly is removed at the time of plant inspection when the reactor is shut down, the magnetic sensor 62 is It inserts between the said outside magnetic coupling 32 and the spool piece 14 partition.

  As described above, the magnetic coupling generates a transmission torque by magnetic interaction between the inner / outer magnetic coupling elements 31 and 32. Therefore, by measuring the magnetism (for example, the magnetic field strength) between the inner / outer magnetic coupling elements 31 and 32, it is possible to confirm the deterioration tendency of the transmission torque.

  Instead of performing magnetic measurement by the magnetic sensor 62, a coil or the like is installed between the outer magnetic coupling 32 and the spool piece 14 partition wall or in a place where the leakage magnetic field is strong outside the spool piece 14, and the magnetic coupling is rotated. The transmission torque of the magnetic coupling can also be confirmed in the same manner by measuring the induced electromotive force accompanying the magnetic field fluctuation generated at that time.

  The magnetic sensor 62, the cable 63, and the recorder 64 are attached when the inspection is performed, and are removed during the operation of the reactor. Of course, it is possible to always connect the magnetic sensor 62, the cable 63, and the recorder 64 to monitor the state of the magnetic coupling, but by temporarily connecting, the cable wiring, control device, etc. required for constant monitoring are possible. Is no longer necessary. In addition, storing and inspecting the first test apparatus outside the containment vessel during plant operation contributes to reducing exposure during inspection work. Further, by storing the magnetic sensor 62 and the like outside the storage container during plant operation, the conditions for irradiating the magnetic sensor 62 and the like with radiation are alleviated, which is also effective in ensuring equipment integrity.

  Next, a second inspection method for the magnetic coupling will be described. When performing the second inspection method, the second test apparatus is used. The second test apparatus includes a shaft 69 to which a torque meter 65, a torque limiter 66, a rotation angle measuring device 67, and an arm 68 that can be turned manually are coupled.

  When performing the second inspection, first, the shaft 69 of the second test apparatus is coupled to the coupling 2 under the spool piece 14 with the motor assembly removed.

  Next, the position of the ball nut 5 is set to the mechanical lower limit state (refer to the section of “Prior Art” for the definition of “mechanical lower limit state”), and the second test apparatus is connected. In this state, torque is applied to the arm 68 in the direction of pulling out the control rod. However, at this time, since the ball nut 5 is in the mechanical lower limit state and cannot be pulled any further, the inner magnetic coupling element 31 cannot rotate in the pulling direction.

  Therefore, the outer magnetic coupling element 32 rotates relative to the inner magnetic coupling 31 according to the magnitude of the applied torque, and a phase difference is generated between the two.

  In the magnetic coupling having an 8-pole magnet as shown in FIG. 2, the maximum transmission torque is generated when the phase difference is about 22.5 degrees as shown in FIG. Therefore, when the torque applied to the arm 68 is gradually increased, the maximum transmission torque is exhibited in the vicinity of a twist angle of about 22.5 degrees. When the arm 68 is further rotated, the torque is lowered and the magnetic coupling is stepped out.

  Using this characteristic, it is possible to confirm that the transmission torque of the magnetic coupling is not less than a predetermined standard value by the following method.

(1) Apply torque to the arm 68 and check the maximum torque with the torque meter 65.
In this case, it is more preferable to grasp the relationship between the rotation angle and the torque of the magnetic coupling by recording the detection value of the rotation angle measuring device 67 and the detection value of the torque meter 65 in association with each other.
When this method is adopted, the torque limiter 66 is not always necessary, but it is preferable to use the torque limiter 66 from the viewpoint of preventing the magnetic coupling from stepping out during the inspection. .

  (2) The torque limit by the torque limiter 66 is set to a predetermined standard value. Then, torque is applied to the arm 68, and it is confirmed that the magnetic coupling does not step out even when torque is applied up to the torque limit value. Although the torque meter 65 and the rotation angle measuring device 67 are not necessarily required, it is also preferable to perform the test while measuring with the rotation angle measuring device 67 using the torque meter 65.

  According to the first and second test methods, the transmission torque of the magnetic coupling can be confirmed without removing the spool piece 14 from the control rod drive mechanism, and the amount of work / process / exposure during the regular inspection can be reduced. It is possible to plan. Further, it is possible to check the transmission torque of the magnetic coupling without removing the spool piece 14 from the control rod drive mechanism, and it is possible to reduce the amount of work / process / exposure during regular inspection.

  In particular, in the second inspection method, since the transmission torque is measured directly rather than measuring the magnetism, the transmission torque can be measured with higher accuracy compared to the first inspection method.

  As described above, according to the present embodiment, it is possible to establish an effective method for confirming the soundness of the magnetic coupling, and by using the above method, a more reliable magnetic coupling is used. A control rod drive mechanism can be constructed.

  Note that the same test as described above can be performed without removing the motor assembly. This method can be realized by configuring the rotating shaft 1 of the electric motor assembly so as to protrude from below the braking brake 34 through the casing, and connecting the second test device to the tip of the protruding rotating shaft 1. Become.

[Third Embodiment]
Next, a third embodiment will be described with reference to FIG. The second embodiment relates to a method and apparatus for inspecting a spool piece and a magnetic coupling that form part of a control rod drive mechanism.

  FIG. 5 shows a state where the spool piece 14 removed from the control rod drive mechanism is installed in the spool piece test apparatus according to the present embodiment.

  First, the configuration of the spool piece test apparatus will be described. The spool piece test apparatus has an upper lid 71 that closes the upper opening of the spool piece 14. A shaft 72 is fixed to the upper lid 71 via a fixing jig 73, and a coupling 70 a that can be connected to the inner magnetic coupling element 31 is provided at the lower end of the shaft 72. A pressure pump 76 for pressurizing the inside of the spool piece 14 and a pressure gauge 77 for pressure measurement are connected to the upper lid 71.

  Next, a method for inspecting the spool piece and the magnetic coupling using the above-described spool piece test apparatus will be described.

  First, the motor assembly and the spool piece 14 are removed from the control rod drive mechanism and placed on the mount 70 of the spool piece test apparatus. Next, the coupling 70 a is coupled to the shaft of the member that supports the separation detection magnet 25. Then, since the shaft 72 cannot rotate, the drive shaft 3 coupled to the inner magnetic coupling element 31 cannot rotate. Next, the upper lid 71 is attached to the spool piece 14 with a bolt 74. At this time, the space between the upper lid 71 and the spool piece 14 is sealed by the O-ring 75.

  Further, the second inspection device described in the second embodiment is connected to the coupling 2 coupled to the shaft of the outer magnetic coupling 42 located at the lower part of the spool piece 14.

  In this state, since the drive shaft 3 cannot rotate, the inner magnetic coupling element 31 cannot rotate even if torque is applied to the arm 68. Accordingly, the outer magnetic coupling element 32 rotates relative to the inner magnetic coupling element 31 according to the magnitude of the torque applied thereto, and a phase difference is generated between the two. By measuring the transmission torque at this time, it becomes possible to measure the maximum transmission torque of the magnetic coupling as in the second embodiment.

  Furthermore, the pressure resistance test of the spool piece 14 can be performed by pressurizing the inside of the spool piece 14 from the pressurizing pump 76.

  When the spool piece 14 is removed from the control rod drive mechanism as in the present embodiment, the outer magnetic coupling element 32 side is fixed, and the second inspection device is connected to the coupling 70a to connect the inner magnetism. Even if the joint element 31 side is rotated, the maximum transmission torque of the magnetic joint can be measured.

  As described above, when the spool piece 14 is inspected, the spool piece 14 is removed from the control rod drive mechanism, and the torque of the magnetic coupling is confirmed by the test apparatus according to the present embodiment installed outside the storage container. Compared with the method described in the second embodiment, the work can be easily performed, which contributes to the reduction of exposure.

  Therefore, when the spool piece 14 is not removed, the torque of the magnetic coupling is checked by the method described in the second embodiment, and when the spool piece 14 is removed, the method described in the third embodiment is used. It is valid.

[Fourth Embodiment]
Next, a fourth embodiment will be described with reference to FIG. The fourth embodiment relates to a method and apparatus for disassembling, inspecting, etc. the spool piece 14 and the magnetic coupling that form part of the control rod drive mechanism.

  FIG. 6 shows a state in which the spool piece 14 is installed in the control rod drive mechanism inspection device according to the present embodiment and the spool piece 14 is disassembled / assembled.

  As shown in FIG. 6, the inspection device has a water tank 78 that can accommodate the spool piece 14 and the magnetic coupling. A stand 79 for placing the spool piece 14 is provided in the water tank 78.

  Furthermore, in the water tank 78, rails 90 and 91 are laid along the axial direction of the spool piece 14 placed on the table 79. On these rails 90 and 91, carriages 84 and 85 are provided so as to be movable along the rails 90 and 91, respectively. The carriages 84 and 85 correspond to the inner magnetic coupling element 31 and the outer magnetic coupling element 32, respectively.

  A shaft 81 is rotatably attached to the carriage 84, and the shaft 81 is located on the same line as the axis of the spool piece 14 placed on the table 79. A coupling 81 is provided at the tip of the shaft 83. The coupling 81 can be coupled to a shaft coupled to the inner magnetic coupling element 31. Similarly, a shaft 82 is rotatably attached to the carriage 85, and the shaft 82 is located on the same line as the axis of the spool piece 14 placed on the table 79. A coupling 80 is provided at the tip of the shaft 82. Coupling 80 can be coupled to a shaft connected to outer magnetic coupling element 32.

  Further, carriages 88 and 89 are provided on the rails 90 and 91 so as to be movable in the axial direction of the spool piece 14 placed on the carriage 79 along the rails 90 and 91, respectively. The carriage 88 is provided with a magnetic jacket 86 that covers the periphery of the inner magnetic coupling element 31. Further, the carriage 89 is provided with a magnetic jacket 87 that covers the periphery of the outer magnetic coupling element 32.

  Further, an ultrasonic oscillation equipment 92 is provided in the water tank 78 so that the spool piece 14 and the like placed in the water tank 78 filled with water can be ultrasonically cleaned. A movable magnet 93 is installed in the water tank 78. Further, this inspection device has a hose 94 for supplying pressurized air.

  Next, the operation will be described. In the state where the inner magnetic coupling element 31 and the outer magnetic coupling element 32 are combined, there is no particular problem because the magnetic field lines are mostly confined in the magnetic coupling, but the inner magnetic coupling element 31 and the outer magnetic coupling element 32 are separated. Then, since magnetic lines of force are dissipated in the surroundings, there is a possibility that a contact accident or the like may occur due to magnetic influences on surrounding equipment and suction of surrounding magnetic bodies.

  On the other hand, when the inspection device as described above is used, the inner magnetic coupling element 31 and the outer magnetic coupling element are fixed with the shafts of the inner magnetic coupling element 31 and the outer magnetic coupling element 32 fixed on the axis of the spool piece 14. Since 32 can be separated and connected, the magnetic coupling can be prevented from being damaged by coming into contact with other devices.

  Further, by covering the periphery of the inner and outer magnetic coupling elements 31 and 32 with the outer casings 86 and 87 of magnetic materials, respectively, magnetic field leakage to the surroundings can be reduced, and the influence on surrounding devices can be reduced.

  Further, by moving the magnet 93 in the water tank 78 in the water tank 78, the magnetic powder and the like in the water tank 78 can be recovered, and the magnetic powder and the like adhere to the surfaces of the inner magnetic coupling element 31 and the outer magnetic coupling element 32. Can be reduced.

  In the present embodiment, the outer casing 86 and 87 of the magnetic body that covers the inner and outer magnetic coupling elements 31 and 32 are provided in the water tank 78, but the outer periphery of the spool piece 14 is also covered with the outer casing of the magnetic body. It may be. Further, even when the inner and outer magnetic coupling elements 31 and 32 and the spool piece 14 are stored and transported, the magnetic influence on the surrounding equipment can be reduced by covering the periphery with a magnetic covering.

  Further, when the inner and outer magnetic coupling elements 31 and 32 are inspected, stored, and transported, the outer and inner magnetic coupling elements 31 and 32 are covered with a nonmagnetic material such as vinyl, thereby adhering foreign matter such as a magnetic material. It is possible to prevent.

  Further, when foreign matter such as magnetic powder adheres to the inner and outer magnetic coupling elements 31 and 32, or when foreign matter adheres to other equipment, the compressed air is ejected from the hose 94 toward the relevant equipment. Thus, it is possible to remove the magnetic powder or other foreign matters.

It is a figure explaining the 1st Embodiment of this invention, Comprising: Sectional drawing along the axial direction which shows roughly one Embodiment of the control-rod drive device by this invention. The conceptual diagram explaining the structure of the magnetic coupling shown in FIG. It is a figure explaining the 2nd Embodiment of this invention, Comprising: The schematic diagram explaining the test | inspection method of a magnetic coupling, and the apparatus for it. The graph explaining an example of the torque characteristic of a magnetic coupling. It is a figure explaining the 3rd Embodiment of this invention, Comprising: The schematic which shows a spool piece test device. It is a figure explaining the 4th Embodiment of this invention, Comprising: The schematic which shows a spool piece inspection apparatus. Sectional drawing along the axial direction which shows the conventional control rod drive device roughly.

Explanation of symbols

4 Ball screw 5 Ball nut 11 Control rod 14 Spool piece 19 Electromagnetic brake (second brake)
20 position detector (first position detector)
30 Scrum position detection probe (second position detection device)
31 Inner magnetic coupling element (first coupling element)
32 Outer magnetic coupling element (second coupling element)
34 Brake brake (first brake)
35 (Induction) motor 36 Thermometer (Temperature measuring means for magnetic coupling)
37 Thermometer (Temperature measuring means for induction motor)
39 Reed switch for magnetic coupling out-of-step detection (Magnetic measuring device)
40 contacts (switches)
41 Power supply device 42 Control device 43 Thermal relay (protective relay)
44 60Hz fixed frequency power supply (first power supply)
45 Variable frequency power supply (second power supply)
48 Magnet A (first magnet)
49 Magnet B (second magnet)
50 Magnet C (third magnet)
51 Magnet D (fourth magnet)
53 Yoke A (first magnetic body)
54 Yoke B (second magnetic body)
55 Yoke C (third magnetic body)
56 Yoke D (4th magnetic body)
57 Sleeve (first jacket)
58 Sleeve (second jacket)
59 Jacket (third and fourth jacket)
62 Magnetic sensor (magnetic measuring device)
65 Torque meter (torque measuring means)
66 Torque limiter 67 Rotation angle measuring device (Rotation angle measuring means)
68 Arm (torque application means)
73 Fixing jig (rotation restraint means)
76 Pressure pump (pressure supply means)
77 Pressure gauge (pressure measuring means)
78 Water tank 84, 88, 90 Bogie and rail (first radial position fixing means)
85, 89, 91 Bogie and rail (second radial position fixing means)
86, 87 Magnetic body covering 93 magnet (means for collecting magnetic body in water tank)

Claims (23)

An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling And a control device for testing a control rod drive device having a drive mechanism for raising and lowering the control rod,
Torque applying means capable of applying torque to a coupling element on the motor assembly side constituting the magnetic coupling or a shaft connected to the coupling element in a state where the spool piece is attached to the drive mechanism;
A torque measuring means for measuring the applied torque;
A test apparatus for a control rod drive device comprising: An electric motor assembly including an electric motor, a spool piece, a magnetic coupling having a pair of coupling elements separated by the spool piece, and a ball nut and a ball screw for converting the rotational movement generated by the electric motor into a linear movement. And a method for testing a control rod drive device having a drive mechanism for transferring the drive force generated by the electric motor to the control rod via the magnetic coupling, the ball nut and the ball screw, and raising and lowering the control rod. ,
With the spool piece attached to the drive mechanism, the position of the ball nut is set to the mechanical lowest limit state or the mechanical maximum upper limit state, and the joint element on the motor assembly side constituting the magnetic joint or the joint element A test method for a control rod drive device, wherein torque is applied to a connected shaft to determine whether or not the magnetic coupling is abnormal. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling And a control device for testing a control rod drive device having a drive mechanism for raising and lowering the control rod,
Torque applying means capable of applying torque to a coupling element on the motor assembly side constituting the magnetic coupling or a shaft connected to the coupling element in a state where the spool piece is attached to the drive mechanism;
A torque limiter for limiting the torque applied by the torque applying means;
A test apparatus for a control rod drive device comprising: An electric motor assembly including an electric motor, a spool piece, a magnetic coupling having a pair of coupling elements separated by the spool piece, and a ball nut and a ball screw for converting the rotational movement generated by the electric motor into a linear movement. And a method for testing a control rod drive device having a drive mechanism for transferring the drive force generated by the electric motor to the control rod via the magnetic coupling, the ball nut and the ball screw, and raising and lowering the control rod. ,
With the spool piece attached to the drive mechanism, the position of the ball nut is set to the mechanical lowest limit state or the mechanical maximum upper limit state, and the joint element on the motor assembly side constituting the magnetic joint or the joint element A test method for a control rod drive device, wherein torque is applied to a connected shaft through a torque limiter set to a predetermined limit value to determine whether the magnetic coupling is abnormal.   In the state where the spool piece is attached to the drive mechanism, the joint element on the motor assembly side or the joint that can be connected to the joint element on the motor assembly side constituting the magnetic coupling or the shaft connected to the joint element. The test apparatus for a control rod drive device according to claim 1 or 3, further comprising a rotation angle measuring means for measuring a rotation angle of a shaft connected to the element.   When applying torque to the joint element on the motor assembly side or the shaft connected to the joint element, the rotation angle of the joint element on the motor assembly side or the shaft connected to the joint element is associated with a torque value. 5. The test method for a control rod drive device according to claim 2, wherein the presence or absence of abnormality of the magnetic coupling is determined based on the measurement result.   The torque is applied to a joint element on the motor assembly side or a shaft connected to the joint element in a state where the motor assembly is detached from the drive mechanism. A test method for a control rod drive device according to claim 1.   With the motor assembly attached to the drive mechanism, the shaft of the motor assembly is rotated from the lower part of the motor assembly, and is connected to the joint element on the motor assembly side or the joint element via the shaft of the motor assembly. The test method for a control rod drive device according to any one of claims 2, 4, and 6, wherein a torque is applied to the shaft. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling In the test device for the control rod drive device provided with a drive mechanism for raising and lowering the control rod, the test device for testing the spool piece,
With the spool piece removed from the drive mechanism, it can be connected to a coupling element on the control rod side constituting the magnetic coupling or a shaft connected to the coupling element, and the coupling element on the control rod side or the coupling Rotation restraining means for restraining rotation of an axis connected to the element;
It is connectable to a joint element on the motor assembly side constituting the magnetic joint or a shaft connected to the joint element, and applies torque to the joint element on the motor assembly side or a shaft connected to the joint element. Torque application means;
A test apparatus for a control rod drive device comprising: An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling In the test device for the control rod drive device provided with a drive mechanism for raising and lowering the control rod, the test device for testing the spool piece,
Torque application that is connectable to a joint element on the control rod side constituting the magnetic joint or a shaft connected to the joint element, and applies torque to the joint element on the control rod side or the shaft connected to the joint element Means,
It is connectable to a joint element on the motor assembly side constituting the magnetic joint or a shaft connected to the joint element, and restrains rotation of the joint element on the motor assembly side or the shaft connected to the joint element. Rotation restraining means;
A test apparatus for a control rod drive device comprising:   It can be connected to one of the joint element on the control rod side or the shaft connected to the joint element, or the joint element on the motor assembly side or the shaft connected to the joint element, and is applied by the torque applying means. The test device for a control rod drive device according to claim 9 or 10, further comprising a torque limiter for limiting the torque to be controlled.   The joint element on the control rod side is connectable to one of the joint element on the control rod side or the shaft connected to the joint element, or the joint element on the motor assembly side or the shaft connected to the joint element. Or a rotation angle measuring means for measuring a rotation angle of a shaft connected to the coupling element, or a coupling element on the motor assembly side or a shaft connected to the coupling element. Or the control rod driving device testing apparatus according to 10.   11. The control rod drive device test according to claim 9, further comprising pressure supply means for pressurizing the inside of the spool piece and pressure measuring means for measuring the pressure inside the spool piece. apparatus. A control rod drive having an electric motor assembly including an electric motor and a spool piece incorporating a magnetic coupling, and having a drive mechanism for transmitting and lowering the control rod by transmitting a driving force generated by the electric motor to the control rod through the magnetic coupling In a storage device for a device, the storage device storing the spool piece,
A storage device for a control rod drive device, comprising a magnetic covering that covers part or all of the spool piece. A control rod drive having an electric motor assembly including an electric motor and a spool piece incorporating a magnetic coupling, and having a drive mechanism for transmitting and lowering the control rod by transmitting a driving force generated by the electric motor to the control rod through the magnetic coupling In a storage device for storing the magnetic coupling,
A storage device for a control rod drive device, comprising a magnetic sheath covering part or all of the magnetic coupling. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling A control rod drive device inspection apparatus having a drive mechanism for raising and lowering the control rod,
A first radial position fixing means for fixing a position of one joint element constituting the magnetic joint or a shaft connected to the joint element in a radial direction;
Second radial position fixing means for fixing the position of the other coupling element constituting the magnetic coupling or the shaft connected to the coupling element in the radial direction,
An inspection device for a control rod drive device, wherein the spool piece is disassembled or assembled while the axes of the spool piece and each joint element are fixed. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling And a storage method of the control rod drive device provided with a drive mechanism for raising and lowering the control rod,
A method of storing a control rod drive device, wherein a part or all of the magnetic coupling is covered and stored with a non-magnetic jacket. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling And a storage method of the control rod drive device provided with a drive mechanism for raising and lowering the control rod,
A method for storing a control rod drive device, wherein a part or all of the magnetic coupling is covered and stored with a magnetic covering. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling A control rod drive device inspection apparatus having a drive mechanism for raising and lowering the control rod,
A water tank for disassembling and assembling the spool piece;
Means for collecting magnetic bodies in the water tank using permanent magnets or induction magnets, and an inspection device for a control rod drive device. An electric motor assembly including an electric motor, a spool piece, and a magnetic coupling having a pair of coupling elements separated by the spool piece, and transmitting a driving force generated by the electric motor to the control rod via the magnetic coupling A control rod drive device inspection method comprising a drive mechanism for raising and lowering the control rod,
An inspection method for a control rod drive device, characterized by spraying pressurized fluid onto the magnetic coupling before or after the inspection to remove foreign matter on the surface of the coupling element. A magnetic coupling including a first coupling element that includes a plurality of magnets and is connected to the first shaft, and a second coupling element that includes a plurality of magnets and is connected to the second shaft. In the torque transmission device,
A first jacket covering all the magnets of the first joint element in a watertight or airtight manner, and a second jacket covering all the magnets in the second joint element in a watertight or airtight manner,
Further, a third outer cover that covers a part or all of the magnets built in the first joint element inside the first outer cover in a water-tight or air-tight manner, and an inner side of the second outer cover, A torque transmission device having a magnetic coupling, characterized in that it comprises at least one of a fourth jacket that covers a part or all of a magnet built in the second coupling element in a watertight or airtight manner. . A control rod drive device that drives a control rod of a nuclear reactor up and down,
A driving mechanism for moving the control rod up and down by transmitting the driving force generated by the motor to the control rod via the torque transmission device, and a torque transmission device according to claim 21;
A power supply device for supplying power to the electric motor;
A control rod drive device comprising: A control rod drive device that drives a control rod of a nuclear reactor up and down,
An electric motor and a torque transmission device according to claim 21, further comprising a drive mechanism that transmits the driving force generated by the electric motor to the control rod via the torque transmission device to raise and lower the control rod;
A first joint element of the torque transmission device is installed inside the spool piece partition wall, and a second joint element of the torque transmission device is installed outside the spool piece partition wall,
In the state where the magnet covered with the third jacket of the first joint element functions and the magnet not covered with the third jacket of the first joint element does not function, A control rod drive device, wherein the torque transmission device has a maximum transmission torque that is equal to or greater than a torque necessary for holding a control rod position during operation.

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