Control rod driving mechanism

Abstract

The utility model belongs to the technical field of nuclear reactors, and particularly discloses a control rod driving mechanism which comprises a barrel, and a driving rod assembly, a gripper assembly and a linear driving assembly are arranged in the barrel. The driving rod assembly comprises a driving rod and a driving rod head, and the driving rod head is connected with the top end of the driving rod; the gripper assembly comprises a gripper and a driving piece for driving the gripper to open and close, and the driving piece can drive the gripper to clamp or loosen the head of the driving rod; the linear driving assembly is used for driving the gripper assembly and the driving rod assembly to linearly move in the barrel. The structure of a chain, a steel wire rope and the like is omitted, so that the whole control rod driving mechanism is simpler in structure.

Description

Technical Field

[0001] The utility model relates to the technical field of nuclear reactors, in particular to a control rod driving mechanism. Background Art

[0002] The control rod drive mechanism (CRDM) is used to move the control rods up and down within the reactor core, thereby enabling important functions such as reactor startup, power regulation, and safe shutdown. Conventional methods for driving the control rods in reactor CRDMs generally include hook drive, drag chain drive, and wire rope drive. In the wire rope drive method, a drive motor typically drives a drum to rotate around a lead screw. The lead screw moves along its axis as it rotates. A wire rope is wound around the drum, raising or lowering the control rods as the drum rotates.

[0003] Fourth-generation nuclear reactors, following the third-generation pressurized water reactor (PWR), are booming, including sodium-cooled fast reactors, lead-bismuth fast reactors, and lava reactors. For these fourth-generation nuclear reactors, the control rod drive mechanism must be short, protruding from the reactor head, and must have excellent sealing performance. Chains and wire ropes are not acceptable. Therefore, there is an urgent need to design a control rod drive mechanism that eliminates these chains and wire ropes. Utility Model Content

[0004] The utility model provides a control rod driving mechanism, the purpose of which is to design a control rod driving mechanism that eliminates structures such as chains and wire ropes.

[0005] The utility model is realized by the following technical solutions: a control rod drive mechanism, wherein a drive rod assembly, a gripper assembly and a linear drive assembly are provided in the cylinder;

[0006] The driving rod assembly includes a driving rod and a driving rod head, wherein the driving rod head is connected to the top end of the driving rod;

[0007] The gripper assembly includes a gripper and a driving member for driving the gripper to open and close, and the driving member can drive the gripper to clamp or release the driving rod head;

[0008] The linear drive assembly is used to drive the gripper assembly and the drive rod assembly to move linearly within the cylinder.

[0009] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0010] In this solution, a gripper assembly is actuated to control the tightening and loosening of the drive rod head, enabling rapid release of the drive rod for rapid insertion into the core and emergency shutdown of the reactor. The linear drive assembly in this solution drives the gripper assembly and the drive rod assembly to move linearly within the cylinder, facilitating adjustment of the position of the control rod, later connected to the drive rod assembly, within the core, thereby enabling the rod to be raised, lowered, and retained.

[0011] In this solution, structures such as chains and wire ropes are eliminated, making the entire control rod drive mechanism structure simple.

[0012] Furthermore, the gripper assembly further includes a housing, at least two grippers are provided, and the grippers are rotatably connected to the housing; the driving member includes an electromagnet, a guide rod, and a driving block, one end of the guide rod extends into the housing and is limited on the housing, and the driving block is located in the housing and slidably fits on the guide rod;

[0013] The driving block is located in the shell, and has an inclined surface on the driving block that abuts against the end of the gripper, and the inclined surface of the driving block is tilted outward from top to bottom; the electromagnet is installed on the shell and is located above the driving block. When the electromagnet is energized, it can suck up the driving block, and the inclined surface of the driving block pushes the gripper to close and clamp the head of the driving rod; when the electromagnet is de-energized, the driving block slides downward along the axial direction of the guide rod, so that the inclined surface of the driving block leaves the end of the gripper, thereby opening the gripper.

[0014] Beneficial effect: In the present solution, the movement state of the driving block in the gripper assembly is changed by turning the electromagnet on and off, and the driving block has an inclined surface that abuts against the end of the gripper. This arrangement can facilitate the upward and downward movement of the driving block to drive the gripper to open and close. When the electromagnet is energized, the electromagnet has magnetism and attracts the driving block upward. At this time, the inclined surface of the driving block will gradually push the gripper to close. The closing of the gripper can clamp the driving rod head in the driving rod assembly. In this way, the linear drive assembly can drive the gripper assembly and the driving rod assembly to move up and down together, thereby driving the control rod connected to the driving rod to move up and down in the core. When the electromagnet is de-energized, the magnetism of the electromagnet is weakened, and the driving block will slide downward under the action of its gravity. During the downward sliding process of the driving block, the inclined surface of the driving block gradually moves away from the gripper, and the gripper will naturally open under the action of its gravity, so that the gripper loses its clamping effect on the driving rod head. At this time, the driving rod assembly as a whole will drive the control rod to be released in time and quickly drop downward and insert into the core to achieve reactor shutdown.

[0015] Furthermore, the driving rod and the driving rod head are provided with mutually connected concave holes, the guide rod can penetrate into the concave hole, and a first buffer spring is provided in the concave hole.

[0016] Beneficial Effects: The recessed hole in this solution facilitates the fit of the guide rod, acting as a guide and facilitating the subsequent re-clamping of the gripper assembly and the drive rod assembly. The first buffer spring provided within the recessed hole cushions the downward movement of the guide rod, preventing excessive insertion speed that could affect the service life of the guide rod and drive rod.

[0017] Furthermore, the driving rod head includes a flat plate portion and a clamping portion, the clamping portion and the flat plate portion are vertically connected to each other, a clamping groove that cooperates with a gripper is provided on the outer side of the clamping portion, and the gripper can be inserted into the clamping groove, and a guide wheel is installed on the outer side of the flat plate portion, and the guide wheel moves along the inner wall of the cylinder.

[0018] Beneficial effects: The clamping portion in the head of the driving rod in this solution is used to cooperate with the gripper clamping, and the flat portion of the head of the driving rod is convenient for installing the guide wheel. In this way, when the driving rod moves up and down, the setting of the guide wheel can reduce the resistance of the driving rod when it moves up and down, making the movement of the driving rod assembly smoother, and the setting of the guide wheel can guide the movement of the driving rod assembly, making the movement of the driving rod assembly more stable.

[0019] Furthermore, the flat plate portion of the driving rod head is in a triangular structure, and three sides of the flat plate portion are connected to guide wheels, and the guide wheels move along the inner wall of the cylinder.

[0020] Beneficial effects: In this solution, gaps are left between the three sides of the flat plate portion of the triangular structure and the cylinder, which facilitates the installation of guide wheels, and installing guide wheels on the three sides of the flat plate portion can improve the smoothness of the movement of the entire drive rod assembly.

[0021] Furthermore, the linear drive assembly includes a transmission mechanism, a drive motor and a screw mechanism. The linear drive mechanism is located at the lower part of the cylinder. The screw mechanism includes a nut and a screw. The nut is threadedly engaged with the screw, and the nut is rotationally engaged with the cylinder. The power of the drive motor is transmitted to the nut through the transmission mechanism to drive the nut to rotate. The screw is slidingly engaged with the inner wall of the cylinder along the axial direction of the cylinder; the screw is connected to the gripper assembly through a connecting rod.

[0022] Beneficial effect: In the linear drive assembly of this scheme, the power of the drive motor is transmitted to the screw mechanism through the transmission mechanism, thereby driving the screw in the screw mechanism to move up and down. Since the screw is connected to the gripper assembly through a connecting rod, the gripper assembly can be driven to move up and down at the same time as the screw moves up and down. In this way, when the gripper in the gripper assembly clamps the drive rod head of the drive rod assembly, the drive rod assembly and the control rod connected to the drive rod can be driven to move in the core, thereby realizing the rise, fall and retention of the control rod.

[0023] Furthermore, the top end of the screw is connected to a screw head, and the connecting rod passes through the gripper assembly, the drive rod head and the screw head in sequence from top to bottom, and a second buffer spring is sleeved on the lower part of the connecting rod.

[0024] Beneficial effect: The setting of the screw head in this solution facilitates the connection and installation of the connecting rod. At the same time, the setting of the second buffer spring can buffer the falling of the driving rod head in the driving rod assembly when the driving rod assembly is released.

[0025] Furthermore, a guide rail is connected to one side of the lower portion of the cylinder, one side of the lead screw head is linearly slidably engaged with the guide rail, and a roller is installed on the other side of the lead screw head, and the roller can move linearly along the inner wall of the cylinder.

[0026] Beneficial effect: In this solution, the screw and the guide rail cooperate to achieve sliding cooperation between the screw and the inner wall of the barrel, which can make the screw rotate and guide the linear movement of the screw. The setting of the roller can make the movement of the screw smoother.

[0027] Furthermore, a magnetostrictive rod position detector is installed on the outside of the cylinder, a permanent magnet is installed on the head of the driving rod, and the magnetostrictive rod position detector is used to sense the magnetic position of the permanent magnet.

[0028] Beneficial Effect: The position of the control rod in the reactor core is determined by the change in the magnetic induction position of the permanent magnet sensed by the magnetostrictive rod position detector, thereby achieving the purpose of controlling the rod position.

[0029] Furthermore, the bottom of the cylinder is sealed with a sealing shell seat, and one end of the sealing shell seat away from the cylinder is sealed with a top cover of the nuclear reactor.

[0030] Beneficial effect: The sealing shell seat in this solution can ensure the sealing between the cylinder and the top cover of the nuclear reactor, thereby preventing the leakage of toxic gases.

[0031] The screw-type hollow control rod drive mechanism of the utility model has the functions of starting the reactor, lifting, inserting or keeping the control rod at the command height. In an emergency working condition, when the electromagnetic gripper cuts off the power to the electromagnetic coil, the control rod drive mechanism can quickly release the drive rod, so that it and the control rod fall under the action of gravity and are quickly inserted into the core to achieve an emergency shutdown of the reactor.

[0032] The opening and closing of the gripper is controlled by the on and off switching of the electromagnet. When the electromagnet is energized, the gripper closes and clamps the head of the drive rod, raising, lowering, and holding it with the lead screw. In an emergency, the electromagnet is de-energized, the gripper opens, and the drive rod, carrying the control rod, is rapidly lowered into the core by gravity, shutting down the reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0034] Figure 1 This is a longitudinal cross-sectional view of an embodiment of a control rod drive mechanism of the present invention;

[0035] Figure 2 for Figure 1 A partial enlarged view of point C in the middle;

[0036] Figure 3 for Figure 1 Partial schematic diagram of the AA position in the middle;

[0037] Figure 4 for Figure 1 Schematic diagram of the B direction.

[0038] Markings and corresponding parts names in the accompanying drawings:

[0039] Cylinder 1, drive motor 2, worm gear mechanism 3, nut 4, lead screw 5, lead screw head 501, roller 502; drive rod 6, drive rod head 601, flat plate 6011, clamping part 6012, first buffer spring 602, guide wheel 603;

[0040] Housing 7, electromagnet 701, gripper 702, first transverse portion 7021, vertical portion 7022, second transverse portion 7023, clamping groove 703;

[0041] Guide rod 8, driving block 801, limiting plate 802;

[0042] Connecting rod 9 , second buffer spring 10 , guide rail 11 , magnetostrictive rod position detector 12 , lead wire 13 , electrical connector 14 , permanent magnet 15 , and sealing housing 16 . DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The schematic implementation methods of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0044] Example

[0045] like Figure 1 As shown, this embodiment provides a control rod drive mechanism, including a cylinder 1, in which a drive rod assembly, a gripper 702 assembly and a linear drive assembly are arranged. The control rod is connected to the drive rod assembly, and the movement of the drive rod assembly controls the state of the control rod.

[0046] The drive rod assembly includes a drive rod and a drive rod head 601, and the drive rod head 601 is connected to the top end of the drive rod. In this embodiment, the drive rod head 601 and the drive rod are integrally formed; the gripper 702 assembly includes a gripper 702 and a driving member that drives the gripper 702 to open and close, and the driving member can drive the gripper 702 to clamp or loosen the drive rod head 601; the linear drive assembly is used to drive the gripper 702 assembly and the drive rod assembly to move linearly in the cylinder 1.

[0047] Combine Figure 2 As shown, the gripper 702 assembly also includes a shell 7, and there are at least two grippers 702. In this embodiment, there are three grippers 702, and the three grippers 702 are evenly distributed circumferentially. The gripper 702 is rotatably connected to the shell 7. In this embodiment, the upper part of the gripper 702 is rotatably connected to the shell 7, and in this embodiment, the gripper 702 includes a first transverse portion 7021, a vertical portion 7022 and a second transverse portion 7023 in sequence. The first transverse portion 7021 and the second transverse portion 7023 are respectively located at the upper end and the lower end of the vertical portion 7022 and are integrally formed with the vertical portion 7022. The first transverse portion 7021 is rotatably connected to the shell 7 via a rotating shaft.

[0048] In this embodiment, the driving part includes an electromagnet 701, a guide rod 8 and a driving block 801. One end of the guide rod 8 extends into the shell 7 and is limited on the shell 7. The driving block 801 is located in the shell 7 and slides on the guide rod 8. In this embodiment, the upper part of the guide rod 8 is connected to the limiting plate 802; the limiting plate 802; is integrally formed with the guide rod 8, the limiting plate 802; is connected to the bottom of the shell 7, and a through hole is provided at the bottom of the shell 7, the guide rod 8 can pass through the through hole, and the diameter of the limiting plate 802; is larger than the diameter of the through hole, so that the guide rod 8 in this embodiment is limited on the shell 7 through the limiting plate 802;, which plays a role in limiting the guide rod 8 and preventing the guide rod 8 from slipping off the shell 7.

[0049] The driving block 801 is located inside the shell 7 and above the limit plate 802. The driving block 801 has an inclined surface that is against the end of the gripper 702. In this embodiment, the first transverse portion 7021 of the gripper 702 can be against the inclined surface of the driving block 801, and the second transverse portion 7023 of the gripper 702 can clamp the driving rod head 601. The inclined surface of the driving block 801 is tilted outward from top to bottom. In this embodiment, the driving block 801 is frustum-shaped, and a through hole is opened in the middle of the driving block 801. The driving block 801 is slidably mounted on the guide rod 8 through the through hole.

[0050] The electromagnet 701 is installed on the housing 7 and is located above the driving block 801. When the electromagnet 701 is energized, it can suck the driving block 801 upward, so that the inclined surface of the driving block 801 pushes the gripper 702 to close and clamp the driving rod head 601; when the electromagnet 701 is de-energized, the driving block 801 slides downward along the axial direction of the guide rod 8 under the action of gravity, so that the inclined surface of the driving block 801 leaves the end of the gripper 702, thereby opening the gripper 702.

[0051] In this embodiment, the driving rod head 601 includes a flat plate portion 6011 and a clamping portion 6012. The clamping portion 6012 and the flat plate portion 6011 are perpendicular to each other and integrally connected. A clamping groove 703 that cooperates with the gripper 702 is provided on the outer side of the clamping portion 6012; the gripper 702 can be inserted into the clamping groove 703; Figure 2 As shown, the clamping groove 703; in this embodiment is trapezoidal, and there are three clamping grooves 703;. The three clamping grooves 703; are evenly distributed circumferentially on the outer periphery of the clamping portion 6012, and the end of the second transverse portion 7023 of the gripper 702 is triangular in shape. The second transverse portion 7023 of the gripper 702 is inserted into the clamping groove 703;. In this embodiment, the shape of the clamping groove 703; and the second transverse portion 7023 facilitates the smooth insertion or removal of the gripper 702 from the clamping groove 703;.

[0052] When the electromagnet 701 is energized, the electromagnet 701 will move the driving block 801 upward, so that the inclined surface of the driving block 801 pushes the first transverse portion 7021 of the gripper 702 to rotate, thereby causing the second transverse portion 7023 of the gripper 702 to clamp the driving rod head 601.

[0053] When the electromagnet 701 is powered off, the driving block 801 slides downward. At this time, the inclined surface on the upper part of the driving block 801 will create a gap with the first horizontal portion 7021 of the gripper 702. The inclined surface of the driving block 801 does not press against the first horizontal portion 7021 of the gripper 702 and cannot produce a tight pressing effect on the first horizontal portion 7021 of the gripper 702. At this time, under the action of the gravity of the gripper 702 and the downward gravity influence of the driving rod assembly as a whole, the first horizontal portion 7021 of the gripper 702 will rotate toward the driving block 801, and the second horizontal portion 7023 of the gripper 702 will rotate in the direction away from the driving rod head 601, and the second horizontal portion 7023 of the gripper 702 will leave the clamping groove 703; so that the gripper 702 as a whole is naturally opened outward.

[0054] Combine Figure 3As shown, in this embodiment, a guide wheel 603 is installed on the outside of the flat plate portion 6011; the guide wheel 603; moves along the inner wall of the cylinder 1. Specifically: the flat plate portion 6011 of the driving rod head 601 has a triangular structure, so that there is an installation gap between the three sides of the flat plate portion 6011 and the cylinder 1, and the three sides of the flat plate portion 6011 are connected to the guide wheels 603; the setting of the guide wheels 603; provides stability and guidance for the up and down movement of the entire driving rod assembly, thereby reducing its movement resistance.

[0055] In this embodiment, the driving rod and the driving rod head 601 are provided with mutually connected recessed holes, and the guide rod 8 can be inserted into the recessed hole. A first buffer spring 602 is provided in the recessed hole. The cooperation between the guide rod 8 and the recessed hole can play a guiding and positioning role for the clamping fit between the gripper 702 assembly and the driving rod assembly, thereby improving the fitting accuracy.

[0056] Combine Figure 1 and Figure 4 As shown, the linear drive assembly in this embodiment includes a transmission mechanism, a drive motor 2 and a screw 5 mechanism. The linear drive mechanism is located at the lower part of the cylinder 1. The screw 5 mechanism includes a nut 4 and a screw 5. The nut 4 is threadedly matched with the screw 5, and the nut 4 is rotated with the cylinder 1. The power of the drive motor 2 is transmitted to the nut 4 through the transmission mechanism to drive the nut 4 to rotate. The transmission mechanism in this embodiment is a worm gear mechanism 3. The screw 5 slides with the inner wall of the cylinder 1 along the axial direction of the cylinder 1. The screw 5 is connected to the gripper 702 assembly through a connecting rod 9. Specifically: in this embodiment, the top of the screw 5 is integrally connected with a screw head 501. The diameter of the screw head 501 is larger than the rod diameter of the screw. The connecting rod 9 passes through the gripper 702 assembly, the drive rod head 601 and the screw head 501 from top to bottom in sequence, combined Figure 3 As shown, in this embodiment, three connecting rods 9 are provided, sequentially distributed at the three corners of the flat portion 6011 of the drive rod head 601. A second buffer spring 10 is sleeved around the lower portion of the connecting rod 9. When the gripper 702 releases the drive rod assembly, the entire drive rod assembly moves downward, and the drive rod head 601 falls onto the second buffer spring 10, which provides a buffering effect on the drive rod head 601.

[0057] A guide rail 11 is connected to one side of the lower portion of the cylinder 1. One side of the lead screw head 501 slides linearly with the guide rail 11. A roller is mounted on the other side of the lead screw head 501. The roller can move linearly along the inner wall of the cylinder 1. The provision of the guide rail 11 can both guide the movement of the lead screw 5 and prevent the lead screw 5 from rotating.

[0058] In this embodiment, a lead wire 13 is spirally arranged on the upper part of the cylinder 1. The lead wire 13 is spirally arranged to produce a stretching and shortening effect, so that it can adapt to the up and down movement of the gripper 702 component and the drive rod component inside the cylinder 1. The top of the cylinder 1 is sealed and connected to the electrical connector 14, and the electromagnet 701 is connected to the external power supply through the lead wire 13 and the electrical connector 14.

[0059] Combine Figure 1 and Figure 2 As shown, in another embodiment, a magnetostrictive rod position detector 12 is installed on the outer side of the cylinder 1, a permanent magnet 15 is installed on the driving rod head 601, and the permanent magnet 15 is sleeved on the driving rod head 601. The magnetostrictive rod position detector 12 is used to sense the magnetic position of the permanent magnet 15.

[0060] The specific implementation process is as follows: Under non-seismic conditions, the control rod drive mechanism, driven by a drive motor, converts the motor's rotational motion into linear motion of the leadscrew through a worm and gear reduction mechanism, thereby raising, lowering, and retaining the control rod assembly. When the control rod drive mechanism in this embodiment is raised or lowered to any desired position, the motor is de-energized, and the self-locking worm gear assembly in the worm and gear reduction mechanism stabilizes the control rod.

[0061] Under non-seismic or seismic conditions, after the control rod drive mechanism receives the rod drop signal, the electromagnet in the gripper assembly loses power, the gripper opens, and the control rod is quickly inserted into the core driven by the drive rod, thereby causing an emergency shutdown of the reactor.

[0062] Combine Figure 1 As shown, in another embodiment, the bottom of the cylinder 1 is sealed with a sealing shell seat 16, and the end of the sealing shell seat 16 away from the cylinder 1 is sealed with the top cover of the nuclear reactor. In this embodiment, a channel is provided in the middle of the sealing shell 7 to facilitate the passage of the driving rod. The top and bottom ends of the sealing shell seat 16 are respectively sealed with the cylinder 1 and the top cover of the nuclear reactor by welding or by screws and gaskets. The shape of the sealing shell seat 16 is adaptively designed according to the design structure of the nuclear reactor top cover to ensure that the sealing shell seat 16 is sealed with the cylinder 1 and the top cover of the nuclear reactor.

[0063] The control rod drive mechanism and external interface equipment are sealed with gaskets.

[0064] In another embodiment, the boundary of the primary circuit inside the cylinder 1 is filled with argon, sodium or lead-bismuth aerosol to prevent the radioactive gas in the reactor from leaking into the reactor hall.

[0065] It should be noted that the above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

[0066] In the description of the present invention, it should be noted that the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0067] In the description of this document, the terms "up", "down", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only used to illustrate the relative position relationship between the various components or components, and do not particularly limit the specific installation orientation of the various components or components.

[0068] In the descriptions of this document, some terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0069] In this document, the terms "installed," "disposed," "provided with," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections, indirect connections through an intermediary, or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0070] The structures, proportions, sizes, etc. drawn in the drawings in this application are only used to match the contents disclosed in this technical briefing document for those skilled in the art to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the efficacy and purpose that can be achieved by this application.

[0071] The terms used in this document are those commonly used in the art currently in consideration of the functions of the present disclosure, but these terms may vary according to the intentions of those skilled in the art, precedents, or new technologies in the art. In addition, specific terms may be selected by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the present disclosure. Therefore, the terms used in the document should not be understood as simple names, but rather as a general description based on the meaning of the terms and the present disclosure.

[0072] Flowcharts or text are used in this document to illustrate the operational steps performed according to the embodiments of the present application. It should be understood that the operational steps in the embodiments of the present application are not necessarily performed in the exact order in which they are described. Instead, the various steps may be processed in reverse order or simultaneously, as needed. Furthermore, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0073] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A control rod drive mechanism, comprising a cylinder, characterized in that: A drive rod assembly, a gripper assembly and a linear drive assembly are provided in the cylinder; The driving rod assembly includes a driving rod and a driving rod head, wherein the driving rod head is connected to the top end of the driving rod; The gripper assembly includes a gripper and a driving member for driving the gripper to open and close, and the driving member can drive the gripper to clamp or release the driving rod head; The linear drive assembly is used to drive the gripper assembly and the drive rod assembly to move linearly within the cylinder.

2. The control rod drive mechanism according to claim 1, wherein: The gripper assembly further includes a housing, at least two grippers are provided, and the grippers are rotatably connected to the housing; the driving member includes an electromagnet, a guide rod, and a driving block, one end of the guide rod extends into the housing and is limited on the housing, and the driving block is located in the housing and slidably fits on the guide rod; The driving block is located in the shell, and has an inclined surface on the driving block that abuts against the end of the gripper, and the inclined surface of the driving block is tilted outward from top to bottom; the electromagnet is installed on the shell and is located above the driving block. When the electromagnet is energized, it can suck up the driving block, and the inclined surface of the driving block pushes the gripper to close and clamp the head of the driving rod; when the electromagnet is de-energized, the driving block slides downward along the axial direction of the guide rod, so that the inclined surface of the driving block leaves the end of the gripper, thereby opening the gripper.

3. The control rod drive mechanism according to claim 2, wherein: The driving rod and the driving rod head are provided with mutually connected concave holes, the guide rod can penetrate into the concave hole, and a first buffer spring is provided in the concave hole.

4. The control rod drive mechanism according to claim 2, wherein: The driving rod head includes a flat plate portion and a clamping portion, the clamping portion and the flat plate portion are vertically connected to each other, a clamping groove that cooperates with a gripper is provided on the outer side of the clamping portion, and the gripper can be inserted into the clamping groove, and a guide wheel is installed on the outer side of the flat plate portion, and the guide wheel moves along the inner wall of the cylinder.

5. The control rod drive mechanism according to claim 4, characterized in that: The flat plate portion of the driving rod head is in a triangular structure, and the three sides of the flat plate portion are connected to the guide wheels.

6. A control rod drive mechanism according to any one of claims 1 to 5, characterized in that: The linear drive assembly includes a transmission mechanism, a drive motor and a screw mechanism. The linear drive mechanism is located at the lower part of the cylinder. The screw mechanism includes a nut and a screw. The nut is threadedly engaged with the screw, and the nut is rotationally engaged with the cylinder. The power of the drive motor is transmitted to the nut through the transmission mechanism to drive the nut to rotate. The screw is slidingly engaged with the inner wall of the cylinder along the axial direction of the cylinder; the screw is connected to the gripper assembly through a connecting rod.

7. The control rod drive mechanism according to claim 6, characterized in that: The top end of the lead screw is connected to a lead screw head, and the connecting rod passes through the gripper assembly, the drive rod head and the lead screw head in sequence from top to bottom. A second buffer spring is sleeved on the lower part of the connecting rod.

8. The control rod drive mechanism according to claim 7, characterized in that: A guide rail is connected to one side of the lower portion of the cylinder, one side of the lead screw head is linearly slidably engaged with the guide rail, and a roller is installed on the other side of the lead screw head, and the roller can move linearly along the inner wall of the cylinder.

9. The control rod drive mechanism according to claim 1, wherein: A magnetostrictive rod position detector is installed on the outer side of the cylinder, a permanent magnet is installed on the head of the driving rod, and the magnetostrictive rod position detector is used to sense the magnetic position of the permanent magnet.

10. The control rod drive mechanism according to claim 1, wherein: The bottom of the cylinder is sealed with a sealing shell seat, and one end of the sealing shell seat away from the cylinder is sealed with the top cover of the nuclear reactor.

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