Control rod clamping structure and built-in control rod drive mechanism

Abstract

The present invention relates to the technical field of hydraulic drive equipment for control rods of nuclear reactors, and in particular to a control rod clamping structure and a driving mechanism provided with the assembly. The control rod clamping structure comprises an inner sleeve, a positioning mechanism and a pin claw mechanism. The inner sleeve is used to be inserted into the shaft holes of several groups of hydraulic cylinders. The inner sleeve is provided with a channel for the control rod drive shaft to move axially. The inner sleeve is provided with at least two mounting positions in sequence along the axial direction, and a hydraulic cylinder is provided between adjacent mounting positions. At least one group of pin claw mechanisms and at least one group of positioning mechanisms are respectively installed on each mounting position. The pin claw mechanism is used to clamp and drive the control rod drive shaft to move, and adjacent pin claw mechanisms and positioning mechanisms are arranged at a preset angle. The present invention can reduce the wear on the control rod drive shaft during grasping and moving, and can eliminate the adverse effects of errors in parts processing and assembly and position deviation on the moving accuracy of the control rod drive shaft.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear reactor control rod hydraulic drive equipment, and in particular to a control rod clamping structure and a built-in control rod drive mechanism. Background Art

[0002] The control rod drive mechanism of a nuclear reactor, referred to as the drive mechanism, is the most critical safety equipment of the reactor, and is responsible for important functions such as the start-up, power regulation and shutdown of the reactor. The control rod drive mechanism can be divided into an external control rod drive mechanism and an internal control rod drive mechanism according to the installation position of the control rod. Among them, the nuclear reactor control rod hydraulic drive system is an internal control rod drive mechanism, and its drive mechanism is placed in the high temperature, high pressure and irradiation environment of the reactor pressure vessel. It uses three hydraulic cylinders for lifting, transferring and clamping to drive the movement of two sets of pin claw mechanisms for transferring and clamping, so as to realize the step-up, step-down and rod-dropping functions of the control rod.

[0003] The existing driving mechanism uses a hydraulic cylinder to drive the pin claw to move, thereby driving the step-up, step-down and rod-dropping movements of the control rod. However, due to the limitation of the connection structure between the existing pin claw and the hydraulic cylinder, it is easy to have errors in parts processing and assembly. In the process of the existing pin claw grabbing the control rod drive shaft and driving it to move, on the one hand, due to the certain deviation between the initial position of the pin claw and the control rod drive shaft, it is difficult for the pin claw to accurately grasp the control rod drive shaft under the deviation and the above-mentioned error conditions, thereby adversely affecting the movement accuracy of the control rod drive shaft; on the other hand, the assembly structure between the pin claw and the hydraulic cylinder is relatively fixed, so under the condition of the above-mentioned error, the movement accuracy of the control rod drive shaft of the driving mechanism will also be adversely affected; on the third hand, the connection structure between the existing pin claw and the hydraulic cylinder is not strong enough, so it is difficult to meet the requirements of the arrangement of the water pipe of the driving mechanism and the overall support, fixation and disassembly. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] To this end, the present invention proposes a control rod clamping structure to solve the problem that errors in parts processing and assembly, as well as position deviations, are easily present between the existing pin claws and the hydraulic cylinder, which makes it difficult for the pin claws to accurately grasp the control rod drive shaft under the deviations and the above-mentioned error conditions, thereby causing the movement accuracy of the control rod drive shaft of the drive mechanism to be adversely affected.

[0006] The present invention also provides a built-in control rod driving mechanism.

[0007] According to an embodiment of one aspect of the present invention, a control rod clamping structure comprises an inner sleeve, a positioning mechanism and a pin claw mechanism, wherein the inner sleeve is used to be inserted into the shaft holes of a plurality of groups of hydraulic cylinders, the inner sleeve is provided with a channel for the control rod drive shaft to move axially, the inner sleeve is provided with at least two mounting positions in sequence along the axial direction, and the hydraulic cylinder is provided between adjacent mounting positions; at least one group of pin claw mechanisms and at least one group of positioning mechanisms are respectively installed on each of the mounting positions, the pin claw mechanisms are used to clamp and drive the control rod drive shaft to move, and the adjacent pin claw mechanisms and the positioning mechanisms are arranged at a preset angle.

[0008] According to one embodiment of the present invention, a mounting hole and a guide groove are respectively provided at each mounting position on the inner sleeve, and the mounting hole and the guide groove are distributed at the preset angle; the pin claw mechanism is passed through the mounting hole, and the positioning mechanism is assembled in the guide groove.

[0009] According to one embodiment of the present invention, the control rod clamping structure also includes a connecting sleeve and a claw sleeve, the pin claw mechanism includes a claw body and a connecting piece, the connecting sleeve and the claw sleeve are arranged on the outside of the inner sleeve from the inside to the outside, one end of the claw body is pivotally connected to the connecting sleeve, and the other end of the claw body is provided with a joint part, the two ends of the connecting piece are respectively pivotally connected to the connecting sleeve and the claw sleeve, and the connecting piece can push the claw body to rotate by rotating, so as to push the claw body to rotate and drive the joint part to pass through the mounting hole and clamp on the control rod drive shaft.

[0010] According to one embodiment of the present invention, a first contact surface is provided on a side of the joint portion facing the control rod drive shaft, and a second contact surface matching the first contact surface is provided on an outer wall of the control rod drive shaft, and the first contact surface and the second contact surface clamp the joint portion on the control rod drive shaft through surface contact.

[0011] According to one embodiment of the present invention, the connecting sleeve is provided with an inner fixing hole, and the claw sleeve is provided with an outer fixing hole, and the positions of the inner fixing hole and the outer fixing hole are arranged in a one-to-one correspondence; one end of the claw body is pivotally installed in one end of the inner fixing hole through a claw shaft, one end of the connecting member is pivotally connected to the other end of the inner fixing hole through a connecting pin, and the other end of the connecting member is pivotally connected to the outer fixing hole through a pin shaft.

[0012] According to one embodiment of the present invention, the positioning mechanism includes a positioning block and a plurality of positioning pins, the connecting sleeve is provided with a positioning hole, and the positioning hole and the internal fixing hole are distributed at the preset angle; one end of the positioning block is fixed in the positioning hole by means of the plurality of positioning pins, and the other end of the positioning block is passed through the guide groove, and the guide groove is arranged parallel to the movement direction of the control rod drive shaft.

[0013] According to one embodiment of the present invention, the control rod clamping structure also includes an axial compensation mechanism, which includes a spring frame and a spring body. The inner sleeve of the hydraulic cylinder is sleeved on the outside of the inner sleeve, and a positioning sleeve is sleeved between the claw sleeve and the inner sleeve of the hydraulic cylinder; a step is provided on the outside of the inner sleeve, the spring frame is sleeved on the outside of the inner sleeve and is located in the positioning sleeve, and the spring frame is arranged between the step and the connecting sleeve; the spring body is press-fitted between the spring frame and the connecting sleeve.

[0014] According to one embodiment of the present invention, the control rod clamping structure includes a transfer pin claw mechanism and a clamping pin claw mechanism, and a first mounting position and a second mounting position are respectively provided on the inner sleeve, the first mounting position is located above the second mounting position, the transfer pin claw mechanism is installed at the first mounting position, and the clamping pin claw mechanism is installed at the second mounting position, and the clamping pin claw mechanism is connected to the inner sleeve through the axial compensation mechanism.

[0015] According to an embodiment of the present invention, the preset angle does not exceed 60°.

[0016] According to another embodiment of the present invention, an internal control rod drive mechanism includes a lifting hydraulic cylinder, a transfer hydraulic cylinder, a clamping hydraulic cylinder, a limit plug and the above-mentioned control rod clamping structure, the inner sleeve of the control rod clamping structure is inserted from top to bottom into the axial holes of the lifting hydraulic cylinder, the transfer hydraulic cylinder, the clamping hydraulic cylinder and the limit plug, and the installation positions of the inner sleeve are respectively arranged between the transfer hydraulic cylinder and the clamping hydraulic cylinder, and between the clamping hydraulic cylinder and the limit plug.

[0017] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0018] A control rod clamping structure according to an embodiment of the present invention has an inner sleeve for passing through the shaft holes of a plurality of groups of hydraulic cylinders, a channel for allowing the control rod drive shaft to move axially is provided in the inner sleeve, at least two mounting positions are sequentially provided in the axial direction of the inner sleeve, and a hydraulic cylinder is provided between adjacent mounting positions, so that the filling and releasing pressure of the hydraulic cylinder is used to drive the inner sleeve cylinder of the hydraulic cylinder to move, thereby driving the pin claw mechanism to grasp the control rod drive shaft and drive the control rod drive shaft to perform axial step-up, step-down and rod-dropping movements along the channel; and the setting of the mounting positions can also make the drop claw position of the pin claw mechanism more accurate, meeting the requirement of accurate grasping under the condition that there is a certain deviation between the pin claw mechanism and the initial position of the control rod drive shaft.

[0019] Furthermore, in the control rod clamping structure, at least one group of pin claw mechanisms and at least one group of positioning mechanisms are respectively installed on each installation position of the inner sleeve, and adjacent pin claw mechanisms and positioning mechanisms are arranged at a preset angle so that the pin claw mechanisms are staggered, and by determining the angle between the pin claw mechanism and the positioning mechanism, it is ensured that the pin claw mechanism acts on the control rod drive shaft in the circumferential direction evenly, thereby reducing the wear on the control rod drive shaft during grasping and movement; the pin claw mechanism is used to clamp and drive the control rod drive shaft to move, so as to meet the driving stability of the same annular groove of the same control rod drive shaft; the positioning mechanism is used to perform circumferential positioning of the pin claw mechanism and even the entire control rod clamping structure, and the positioning mechanism can also ensure that the distance between each pin claw mechanism can be fine-tuned to compensate for the errors in parts processing and assembly, eliminate the adverse effects of the errors in parts processing and assembly and position deviation on the movement accuracy of the control rod drive shaft, and meet the performance characteristics requirements of the drive mechanism.

[0020] Furthermore, the control rod clamping structure can achieve mechanical anti-loosening and anti-rotation between various components to meet the requirements of the layout of the drive mechanism water pipe and overall support, fixation and disassembly; and can also adapt to the normal operation under the high temperature and high pressure environment of the nuclear reactor. It can be seen that the control rod clamping structure can not only meet the engineering application of the built-in control rod drive mechanism, but also provide a better choice for the drive structure design of the hydraulic cylinder drive mechanism in other industrial fields.

[0021] In an internal control rod drive mechanism of an embodiment of the present invention, the inner sleeve of the control rod clamping structure is sleeved from top to bottom in the axial holes of the lifting hydraulic cylinder, the transmission hydraulic cylinder, the clamping hydraulic cylinder and the limit plug, and the installation position of the inner sleeve is respectively set between the transmission hydraulic cylinder and the clamping hydraulic cylinder, and between the clamping hydraulic cylinder and the limit plug. By setting the above control rod clamping structure, the internal control rod drive mechanism has all the advantages of the above control rod clamping structure, which will not be repeated here.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 1. It is a schematic diagram of the installation structure of the control rod clamping structure in the built-in control rod drive mechanism according to an embodiment of the present invention;

[0025] Figure 2 is a structural schematic diagram of a transmission pin pawl mechanism in a released state according to an embodiment of the present invention;

[0026] Figure 3 It is a structural schematic diagram of the transmission pin claw mechanism in the grasping state according to the embodiment of the present invention;

[0027] Figure 4 It is a comparative structural diagram of the transmission pin claw mechanism of the embodiment of the present invention in a grasping state and a moving state;

[0028] Figure 5 is a schematic structural diagram of a clamping pin claw mechanism in a released state according to an embodiment of the present invention;

[0029] Figure 6 It is a structural schematic diagram of the clamping pin claw mechanism in the grasping state according to the embodiment of the present invention;

[0030] Figure 7 This is a schematic diagram of the structure of the inner sleeve in an embodiment of the present invention;

[0031] Figure 8 It is a schematic structural diagram of a transfer connection sleeve according to an embodiment of the present invention;

[0032] Fig. 9 It is a schematic structural diagram of a transfer claw sleeve according to an embodiment of the present invention;

[0033] Fig.10 2 is a schematic structural diagram of a clamping claw sleeve according to an embodiment of the present invention;

[0034] Fig.11 It is a schematic structural diagram of a clamping connection sleeve according to an embodiment of the present invention.

[0035] Reference numerals:

[0036] 1: Lifting hydraulic cylinder; 2: Inner sleeve; 201: First mounting hole; 202: Second mounting hole; 3: Transfer connecting sleeve; 301: First inner fixing hole; 302: First positioning hole; 4: Transfer hydraulic cylinder; 5: Transfer pin claw mechanism; 6: Clamp hydraulic cylinder; 7: Clamp pin claw mechanism; 8: Transfer inner sleeve cylinder; 9: Anti-loosening screw; 10: Anti-loosening rod; 11: Control rod drive shaft; 12: Transfer claw sleeve; 1201: First outer fixing hole; 13: Positioning Pin; 14: positioning block; 15: claw shaft; 16: claw body; 17: connecting pin; 18: connecting piece; 19: pin shaft; 20: clamping claw sleeve; 2001: second outer fixing hole; 21: limiting plug; 22: clamping inner sleeve cylinder; 23: positioning sleeve; 24: clamping spring frame; 25: clamping spring body; 26: clamping connecting sleeve; 2601: second inner fixing hole; 2602: second positioning hole; 27: first contact surface; 28: second contact surface. DETAILED DESCRIPTION

[0037] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0038] like Figures 1 to 11 As shown, an embodiment of the present invention provides a control rod clamping structure (the embodiment of the present invention is referred to as "structure" for short), and based on the structure provides a built-in control rod driving mechanism (the embodiment of the present invention is referred to as "driving mechanism" for short).

[0039] like Figure 1 As shown, the structure includes an inner sleeve 2, a positioning mechanism and a pin claw mechanism. The inner sleeve 2 is used to be inserted into the shaft holes of several groups of hydraulic cylinders. The inner sleeve 2 is provided with a channel for the control rod drive shaft 11 to move axially. The channel is arranged along the axial direction of the inner sleeve 2, that is, the inner sleeve 2 is constructed as an axial hollow structure, so that the control rod drive shaft 11 can be coaxially inserted in the channel and can move axially along the channel. The inner sleeve 2 is provided with at least two installation positions in sequence along the axial direction, and a hydraulic cylinder is provided between adjacent installation positions. At least one group of pin claw mechanisms and at least one group of positioning mechanisms are respectively installed on each installation position of the inner sleeve 2. The pin claw mechanism is used to clamp and drive the control rod drive shaft 11 to move, so as to meet the driving stability of the same ring groove of the same control rod drive shaft 11.

[0040] In the embodiment of the present invention, the hydraulic cylinder can drive the inner sleeve cylinder of the hydraulic cylinder and the inner sleeve 2 to make axial relative movement by charging and releasing pressure, thereby driving the pin claw mechanism to grab the control rod drive shaft 11 and drive the control rod drive shaft 11 to make axial step-up, step-down and rod-dropping movements along the channel. The setting of different installation positions on the inner sleeve 2 can clearly define the axial claw drop position of the pin claw mechanism on the control rod drive shaft 11, further improve the accuracy of the claw drop position of the pin claw mechanism, thereby meeting the requirement of accurate grasping under the condition that there is a certain deviation between the initial position of the pin claw mechanism and the control rod drive shaft 11.

[0041] In the embodiment of the present invention, adjacent pin claw mechanisms and positioning mechanisms are arranged at a preset angle so that the pin claw mechanisms are staggered, and by determining the angle between the pin claw mechanisms and the positioning mechanisms, it is ensured that the points of action of the pin claw mechanisms on the control rod drive shaft 11 in the circumferential direction are uniform, thereby reducing the wear on the control rod drive shaft 11 during grasping and moving.

[0042] Preferably, the preset angle does not exceed 60°, that is, the angle between adjacent pin claw mechanisms and positioning mechanisms does not exceed 60°, that is, most preferably, three groups of pin claw mechanisms are arranged at intervals of 120° along the side wall of the inner sleeve 2 on the radial cross section of the same installation position of the inner sleeve 2, and one group of positioning mechanisms is arranged between two adjacent groups of pin claw mechanisms, then the angle between adjacent positioning mechanisms and pin claw mechanisms is 60°. This angle setting can ensure that each pin claw mechanism is evenly staggered, and that the pin claw mechanism and the positioning mechanism are evenly staggered, and can also ensure that the pin claw mechanism has a more uniform action point on the circumferential direction of the control rod drive shaft 11, which is convenient for force application, thereby further reducing the wear of the pin claw mechanism on the control rod drive shaft 11 during grasping and moving.

[0043] In the embodiment of the present invention, the positioning mechanism is used to perform circumferential positioning on the pin claw mechanism and even the entire control rod clamping structure, and the positioning mechanism can also ensure that the distance between each pin claw mechanism can be fine-tuned to compensate for errors in parts processing and assembly, eliminate the adverse effects of errors in parts processing and assembly and position deviations on the movement accuracy of the control rod drive shaft 11, and meet the performance characteristic requirements of the drive mechanism.

[0044] In the embodiment of the present invention, the control rod clamping structure can also achieve mechanical anti-loosening and anti-rotation between the various components to meet the requirements of the drive mechanism water pipe layout and overall support, fixation and disassembly; and can also adapt to normal operation under the high temperature and high pressure environment in the nuclear reactor.

[0045] It can be seen that the structure described in the embodiment of the present invention can not only meet the engineering application of the built-in control rod drive mechanism, but also provide a better choice for the drive structure design of the hydraulic cylinder drive mechanism in other industrial fields.

[0046] like Figure 1As shown, the driving mechanism of the present invention comprises a lifting hydraulic cylinder 1, a transmission hydraulic cylinder 4, a clamping hydraulic cylinder 6, a stopper 21 and a control rod clamping structure of the present invention. The inner sleeve 2 of the control rod clamping structure is sleeved from top to bottom in the axial holes of the lifting hydraulic cylinder 1, the transmission hydraulic cylinder 4, the clamping hydraulic cylinder 6 and the stopper 21, and the installation positions of the inner sleeve 2 are respectively arranged between the transmission hydraulic cylinder 4 and the clamping hydraulic cylinder 6, and between the clamping hydraulic cylinder 6 and the stopper 21. By arranging the control rod clamping structure, the driving mechanism has all the advantages of the structure, which will not be described in detail here.

[0047] It is understandable that the drive mechanism of the present invention may not be provided with the limiting plug 21 below the second installation position. The purpose of providing the limiting plug 21 is, on the one hand, to accurately locate the position of the claw body 16 of the claw mechanism of the pin 13 in the released state, so as to prevent the claw body 16 from entering the inner sleeve 2 and affecting the movement of the control rod drive shaft 11; on the other hand, to cooperate with the axial compensation mechanism described below to solve the problem of inaccurate grasping position caused by a certain deviation between the initial position of the pin claw mechanism and the control rod drive shaft 11.

[0048] In the embodiment of the present invention, the structure preferably includes a transmission pin claw mechanism 5 and a clamping pin claw mechanism 7, and a first mounting position and a second mounting position are respectively provided on the inner sleeve 2, and the first mounting position is located above the second mounting position. Figure 1 Preferably, as shown Figure 7 As shown, the first installation position is located between the transmission hydraulic cylinder 4 and the clamping hydraulic cylinder 6, and the transmission pin claw mechanism 5 is installed at the first installation position and linked with the inner sleeve cylinder of the transmission hydraulic cylinder 4. The second installation position is located between the clamping hydraulic cylinder 6 and the limit plug 21, and the clamping pin claw mechanism 7 is installed at the second installation position and linked with the inner sleeve cylinder of the clamping hydraulic cylinder 6, and the clamping pin claw mechanism 7 is connected to the inner sleeve 2 through an axial compensation mechanism. Positioning mechanisms are also correspondingly arranged at the first installation position and the second installation position, so that the circumferential position of the transmission pin claw mechanism 5 and the clamping pin claw mechanism 7, as well as the starting position of the control rod drive shaft 11 can be accurately positioned respectively, and the positioning mechanism can also axially position the transmission pin claw mechanism 5 and the clamping pin claw mechanism 7 during operation. The specific positioning method is shown in the following content and will not be repeated here.

[0049] In one embodiment, the inner sleeve 2 is provided with a mounting hole and a guide groove at each mounting position, a pin claw mechanism is inserted into the mounting hole, and a positioning mechanism is installed in the guide groove. Figure 7The first mounting holes 201 and the second mounting holes 202 shown are preferably at least three in number, and the angle between adjacent first mounting holes 201 does not exceed 120°; similarly, the angle between adjacent second mounting holes 202 does not exceed 120°. The mounting holes and the guide grooves are arranged at a preset angle, preferably the preset angle does not exceed 60° as described above, so that the mounting holes and the guide grooves are staggeredly distributed on the circumference of the side wall of the inner sleeve 2. The structural arrangement of the inner sleeve 2 can use the mounting holes and the guide grooves to accurately position the pin claw mechanism and the positioning mechanism in the axial position and circumferential position of the inner sleeve 2, so that the pin claw mechanism and the control rod drive shaft 11 can achieve accurate axial and circumferential positioning, further promoting the pin claw mechanism on the control rod drive shaft 11. The action point is more uniform, ensuring that the movement of the control rod drive shaft 11 is more stable and reliable.

[0050] In one embodiment, the control rod clamping structure further includes a connecting sleeve and a claw sleeve, and the pin claw mechanism includes a claw body 16 and a connecting member 18. The connecting sleeve and the claw sleeve are arranged on the outside of the inner sleeve 2 from the inside to the outside. One end of the claw body 16 is pivotally connected to the connecting sleeve, and the other end of the claw body 16 is provided with a joint portion; the two ends of the connecting member 18 are pivotally connected to the connecting sleeve and the claw sleeve respectively, and the connecting member 18 can push the claw body 16 to rotate by rotating, so as to push the claw body 16 to rotate and drive the joint portion to pass through the mounting hole and clamp on the control rod drive shaft 11, thereby realizing the state switching of the pin claw mechanism.

[0051] Furthermore, the connecting sleeve is provided with an inner fixing hole, and the claw sleeve is provided with an outer fixing hole. Preferably, the number of inner fixing holes and outer fixing holes on the same mounting position matches the number of mounting holes, and the positions of the inner fixing holes and the outer fixing holes are arranged in a one-to-one correspondence, so as to form an integral connection structure of a set of pin claw mechanisms. One end of the claw body 16 is pivotally mounted in one end of the inner fixing hole through the claw shaft 15, one end of the connecting member 18 is pivotally connected to the other end of the inner fixing hole through the connecting pin 17, and the other end of the connecting member 18 is pivotally connected to the outer fixing hole through the pin shaft 19.

[0052] It is understandable that in the structure of the embodiment of the present invention, the claw sleeve, the connecting sleeve, the inner sleeve 2 and the control rod drive shaft 11 are all coaxially arranged. According to the specific structure of the pin claw mechanism mentioned above, it can be known that the inner sleeve cylinder of the hydraulic cylinder can drive the claw sleeve to move axially during the axial movement, and the movement of the claw sleeve drives the connecting member 18 to rotate. On the one hand, the movement of the claw sleeve pushes the claw body 16 to rotate and drives the joint part to clamp on the control rod drive shaft 11; on the other hand, the continued movement of the claw sleeve can drive the connecting sleeve to move and drive the claw body 16 to move axially relative to the control rod drive shaft 11, so as to drive the control rod drive shaft 11 to perform step-up, step-down or rod-dropping movement in the channel of the inner sleeve 2.

[0053] In one embodiment, the positioning mechanism includes a positioning block 14 and a plurality of positioning pins 13. A positioning hole is provided on the connecting sleeve, one end of the positioning block 14 is fixed in the positioning hole by a plurality of positioning pins 13, and the other end of the positioning block 14 is inserted into the guide groove, and the guide groove is arranged parallel to the movement direction of the control rod drive shaft 11. The positioning hole and the inner fixing hole are arranged at a preset angle so that the positioning hole of the connecting sleeve and the inner fixing hole are staggered with each other, and can be adapted to the position of the guide groove and the mounting hole on the inner sleeve 2, so as to facilitate the installation of the claw body 16 and the installation of the positioning block 14. It can be seen that the guide groove can not only implement the circumferential positioning of the positioning block 14 between the inner sleeve 2 and the connecting sleeve, but also ensure the axial positioning between the connecting sleeve and the inner sleeve 2 during the movement of the connecting sleeve, thereby improving the movement stability and grasping accuracy of the control rod drive shaft 11. The positioning mechanism can also use the axial movement of the positioning block 14 in the guide groove to provide assembly margin for fine-tuning the distance between each pin claw mechanism, thereby compensating for the errors in part processing and assembly.

[0054] In one embodiment, the structure further includes an axial compensation mechanism, which can drive the claw body 16 to produce a certain axial displacement during the state switching of the pin claw mechanism, especially during the process of switching from the release state to the grasping state, so as to compensate for the error in the initial axial position of the control rod drive shaft 11 and the pin claw mechanism.

[0055] Furthermore, the axial compensation mechanism includes a spring frame and a spring body. The inner sleeve of the hydraulic cylinder is sleeved outside the inner sleeve 2, and a positioning sleeve 23 is sleeved between the claw sleeve and the inner sleeve of the hydraulic cylinder. The positioning sleeve 23 can provide more space for the installation gap between the inner sleeve of the hydraulic cylinder and the claw sleeve, and can ensure the reliable connection and accurate axial positioning between the inner sleeve of the hydraulic cylinder and the claw sleeve. A step is provided outside the inner sleeve 2, and the spring frame is sleeved outside the inner sleeve 2 and located in the positioning sleeve 23, and the spring frame is arranged between the step and the connecting sleeve; the spring body is pressed between the spring frame and the connecting sleeve. The axial compensation mechanism uses the axial spacing between the spring frame and the connecting sleeve to limit the maximum value of the axial error compensation, and uses the elastic force of the spring body to drive the claw body 16 to produce a certain axial displacement during the rotation process, thereby compensating the error of the initial axial position of the control rod drive shaft 11 and the pin claw mechanism.

[0056] It should be noted that the pin-pawl mechanism described in the embodiment of the present invention has at least three states, specifically including: a released state, a grasped state, and a moving state. For example: Figure 2 The transmission pin pawl mechanism 5 is shown in a released state. Figure 3 The transfer pin pawl mechanism 5 is shown in the grasping state, Figure 4 The figure shows the comparison between the transmission pin claw mechanism 5 in the grasping state and the transmission pin claw mechanism 5 in the moving state. Figure 5The clamping pin claw mechanism 7 is shown in a released state. Figure 6 The clamping pin mechanism 7 is shown in the gripping state.

[0057] Depend on Figure 2 and Figure 3 Compare and Figure 5 and Figure 6 It can be seen from the comparison that in the pin claw mechanism of the embodiment of the present invention, one end of the claw body 16 is constructed as a rotating end with an arc-shaped outer edge structure, and the other end of the claw body 16 is constructed as a pushing surface matching the connecting member 18, and a first contact surface 27 facing the control rod drive shaft 11, the first contact surface 27 and the pushing surface are arranged in opposite directions, and because the side wall surface of the control rod drive shaft 11 is a corrugated structure, it is preferred that the downward inclined surface in the corrugated structure is used as the second contact surface 28 arranged on the outer wall of the control rod drive shaft 11, and the structures of the first contact surface 27 and the second contact surface 28 match each other, so that the surface contact between the first contact surface 27 and the second contact surface 28 can be used to fit the joint part in the groove of the corrugated structure of the control rod drive shaft 11, and then the joint parts of the claw bodies 16 of multiple pin claw mechanisms are used to fit in the above-mentioned groove from all directions at the same time, so as to realize the clamping between the pin claw mechanism and the control rod drive shaft 11.

[0058] It is understandable that in order to better achieve the resetting of the claw body 16, a reset spring is preferably sleeved on the claw shaft 15, and the connecting member 18 gradually moves away from the joint of the claw body 16 during the reverse movement. Then, the claw body 16 can move away from the control rod drive shaft 11 along with the connecting member 18 under the elastic driving action of the reset spring, thereby realizing the state switching process of the pin claw mechanism from the grasping state to the releasing state.

[0059] Specifically, Figure 8 As shown, the bottom of the side wall of the transmission connection sleeve 3 of the transmission pin claw mechanism 5 is distributed with three first internal fixing holes 301 and three first positioning holes 302. The first internal fixing holes 301 are arranged in a one-to-one correspondence with the positions of the first mounting holes 201 of the inner sleeve 2, and the first positioning holes 302 are arranged in a one-to-one correspondence with the positions of the guide grooves on the first mounting position of the inner sleeve 2. The first mounting hole 201, the first internal fixing hole 301 and the first external fixing hole 1201 are respectively constructed as oblong holes. Fig. 9 As shown, three first external fixing holes 1201 are distributed on the bottom of the side wall of the transmission claw sleeve 12 of the transmission pin claw mechanism 5 , and the positions of the first external fixing holes 1201 are arranged in one-to-one correspondence with the positions of the first internal fixing holes 301 .

[0060] like Figure 2 and Figure 3As shown, the rotating end of the claw body 16 of the transmission pin claw mechanism 5 is pivotally connected to the upper position of the first inner fixing hole 301 through the claw shaft 15, one end of the connecting member 18 is pivotally connected to the lower position of the first inner fixing hole 301 through the connecting pin 17, and the other end of the connecting member 18 is pivotally connected to the first outer fixing hole 1201 through the pin shaft 19. In addition, the top of the transmission connecting sleeve 3 is fixedly connected to the bottom of the transmission inner sleeve cylinder 8 of the transmission hydraulic cylinder 4.

[0061] When the transmission inner sleeve cylinder 8 of the transmission hydraulic cylinder 4 is in the process of axial movement, the axial movement of the transmission claw sleeve 12 drives the connecting piece 18 to rotate, so that the joint part of the push claw body 16 is clamped on the control rod driving shaft 11, thereby realizing the process of switching the transmission pin claw mechanism 5 from the loose state to the grasping state. Figure 4 As shown, the transmission claw sleeve 12 continues to make axial movement in the same direction to drive the transmission connection sleeve 3 to make axial movement through the axial movement of the connecting piece 18, thereby driving the control rod drive shaft 11 to make axial movement along the channel of the inner sleeve 2 through the claw body 16, thereby realizing the process of switching the transmission pin claw mechanism 5 from the grasping state to the moving state.

[0062] During the state switching process of the above-mentioned transmission pin pawl mechanism 5, since the positioning block 14 is fixed in the first positioning hole 302 and moves in the guide groove along with the axial movement of the transmission connecting sleeve 3, the axial and circumferential positioning of the transmission pin pawl mechanism 5 during the state switching process is improved with higher accuracy and stability.

[0063] by Figure 4 For example, the transmission claw sleeve 12 makes an axial upward movement. During the process of the transmission pin claw mechanism 5 switching from the grasping state to the moving state, the inner sleeve 2 remains stationary and the control rod drive shaft 11 rises as a whole to a height H under the driving action of the transmission pin claw mechanism 5.

[0064] Similarly, if Fig.11 As shown, the bottom of the side wall of the clamping connection sleeve 26 of the clamping pin claw mechanism 7 is provided with three second inner fixing holes 2601 and three second positioning holes 2602. The second inner fixing holes 2601 are arranged in a one-to-one correspondence with the positions of the second mounting holes 202 of the inner sleeve 2, and the second positioning holes 2602 are arranged in a one-to-one correspondence with the positions of the guide grooves on the second mounting position of the inner sleeve 2. The second mounting hole 202, the second inner fixing hole 2601 and the second outer fixing hole 2001 are respectively constructed as oblong holes. Fig.10 As shown, three second external fixing holes 2001 are distributed on the bottom of the side wall of the clamping claw sleeve 20 of the clamping pin claw mechanism 7, and the positions of the second external fixing holes 2001 correspond to the positions of the second internal fixing holes 2601. Figure 5 and Figure 6As shown, the rotating end of the claw body 16 of the clamping pin claw mechanism 7 is pivotally connected to the upper position of the second inner fixing hole 2601 through the claw shaft 15, one end of the connecting member 18 is pivotally connected to the lower position of the second inner fixing hole 2601 through the connecting pin 17, and the other end of the connecting member 18 is pivotally connected to the second outer fixing hole 2001 through the pin shaft 19. In addition, the top of the clamping connecting sleeve 26 is fixedly connected to the bottom of the clamping inner sleeve cylinder 22 of the clamping hydraulic cylinder 6 through the positioning sleeve 23. In addition, a step is provided on the inner sleeve 2, which is located between the bottom of the clamping inner sleeve cylinder 22 and the top of the clamping connecting sleeve 26, and an axial compensation mechanism is installed between the step and the clamping connecting sleeve 26, that is, the clamping spring frame 24 is fixed between the step and the clamping connecting sleeve 26, the lower part of the clamping spring frame 24 is open, and the clamping spring body 25 is sleeved in the opening of the clamping spring frame 24 and elastically connected between the clamping spring frame 24 and the top of the clamping connecting sleeve 26.

[0065] Then, during the axial movement of the clamping inner sleeve cylinder 22 of the clamping hydraulic cylinder 6, the axial movement of the clamping claw sleeve 20 is driven by the positioning sleeve 23 to drive the connecting member 18 to rotate, so as to push the joint of the claw body 16 to clamp on the control rod drive shaft 11, thereby realizing the process of switching the clamping pin claw mechanism 7 from the loose state to the grasping state. The clamping claw sleeve 20 continues to make axial movement in the same direction to drive the clamping connection sleeve 26 to make axial movement through the axial movement of the connecting member 18, thereby driving the control rod drive shaft 11 to make axial movement along the channel of the inner sleeve 2 through the claw body 16, thereby realizing the process of switching the clamping pin claw mechanism 7 from the grasping state to the moving state.

[0066] During the state switching process of the clamping pin claw mechanism 7, since the positioning block 14 is fixed in the second positioning hole 2602 and moves in the guide groove along with the axial movement of the clamping connecting sleeve 26, the axial and circumferential positioning of the clamping pin claw mechanism 7 during the state switching process is improved with higher accuracy and stability.

[0067] In the state switching process of the clamping pin claw mechanism 7, the clamping spring frame 24 and the clamping spring body 25 provide compensation for the axial displacement of the clamping connection sleeve 26 through elastic force, thereby providing elastic axial compensation for the error of the initial axial position of the control rod drive shaft 11 and the clamping pin claw mechanism 7.

[0068] It is understandable that in order to achieve mechanical anti-loosening and anti-rotation between the various components and meet the requirements of the arrangement of the water pipe of the driving mechanism and the overall support, fixation and disassembly, the structure described in the embodiment of the present invention is connected to the inner sleeve of the hydraulic cylinder through a fastening assembly. The fastening assembly includes an anti-loosening screw 9 and an anti-loosening rod 10. Figures 2 to 4As shown, the anti-loosening screw 9 passes through the side wall of the transmission claw sleeve 12 in the radial direction and is locked in the side wall of the transmission inner sleeve cylinder 8 of the transmission hydraulic cylinder 4. An anti-loosening rod 10 is installed on the side of the anti-loosening screw 9 to further increase the tightening force of the anti-loosening screw 9 by using the anti-loosening rod 10 to prevent the anti-loosening screw 9 from loosening. Figure 5 and Figure 6 As shown, one anti-loosening screw 9 radially passes through the side wall of the clamping claw sleeve 20 and is locked in the bottom end of the side wall of the positioning sleeve 23, and the other anti-loosening screw 9 radially passes through the top end of the side wall of the positioning sleeve 23 and is locked in the side wall of the clamping inner sleeve cylinder 22 of the clamping hydraulic cylinder 6, thereby using two sets of fastening components to fix the clamping claw sleeve 20, the positioning sleeve 23 and the clamping inner sleeve cylinder 22; anti-loosening rods 10 are respectively installed on the sides of the two anti-loosening screws 9.

[0069] It is understandable that in order to adapt to the normal operation under the high temperature and high pressure environment in the nuclear reactor, the structure described in the embodiment of the present invention is made of high temperature and high pressure resistant materials. For example, the material of the claw body 16 and the connecting piece 18 is selected from the high temperature and corrosion resistant stainless steel and its alloy material of model AMS5787; for another example, the material of the claw shaft 15, the connecting pin 17 and the pin shaft 19 is selected from the high temperature and corrosion resistant stainless steel and its alloy material of model AMS5759, so as to meet the wear resistance requirements under the high temperature and high pressure environment.

[0070] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0071] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0072] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0073] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0074] The above embodiments are only used to illustrate the present invention, but not to limit the present invention. Although the present invention is described in detail with reference to the embodiments, it should be understood by those skilled in the art that various combinations, modifications or equivalent substitutions of the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and should be included in the scope of the claims of the present invention.

Claims

1. A control rod clamping structure, characterized in that: The invention comprises an inner sleeve, a positioning mechanism and a pin claw mechanism. The inner sleeve is used to be inserted into the shaft holes of several groups of hydraulic cylinders. The inner sleeve is provided with a channel for the control rod drive shaft to move axially. The inner sleeve is provided with at least two installation positions in sequence along the axial direction, and the hydraulic cylinder is provided between adjacent installation positions. At least one group of pin claw mechanisms and at least one group of positioning mechanisms are respectively installed on each installation position. The pin claw mechanisms are used to clamp and drive the control rod drive shaft to move. The adjacent pin claw mechanisms and the positioning mechanisms are arranged at a preset angle.

2. The control rod clamping structure according to claim 1, characterized in that: The inner sleeve is provided with a mounting hole and a guide groove at each mounting position, and the mounting hole and the guide groove are distributed at the preset angle; the pin claw mechanism is passed through the mounting hole, and the positioning mechanism is installed in the guide groove.

3. The control rod clamping structure according to claim 2, characterized in that: The control rod clamping structure also includes a connecting sleeve and a claw sleeve, and the pin claw mechanism includes a claw body and a connecting piece. The connecting sleeve and the claw sleeve are arranged on the outside of the inner sleeve from the inside to the outside. One end of the claw body is pivotally connected to the connecting sleeve, and the other end of the claw body is provided with a joint part. The two ends of the connecting piece are respectively pivotally connected to the connecting sleeve and the claw sleeve. The connecting piece can push the claw body to rotate by rotating, so as to push the claw body to rotate and drive the joint part to pass through the mounting hole and clamp on the control rod drive shaft.

4. The control rod clamping structure according to claim 3, characterized in that: A first contact surface is provided on a side of the joint portion facing the control rod drive shaft, and a second contact surface matching the first contact surface is provided on an outer wall of the control rod drive shaft. The first contact surface and the second contact surface clamp the joint portion on the control rod drive shaft through surface contact.

5. The control rod clamping structure according to claim 3, characterized in that: The connecting sleeve is provided with an inner fixing hole, and the claw sleeve is provided with an outer fixing hole, and the positions of the inner fixing hole and the outer fixing hole are arranged in a one-to-one correspondence; one end of the claw body is pivotally installed in one end of the inner fixing hole through a claw shaft, one end of the connecting member is pivotally connected to the other end of the inner fixing hole through a connecting pin, and the other end of the connecting member is pivotally connected to the outer fixing hole through a pin shaft.

6. The control rod clamping structure according to claim 5, characterized in that: The positioning mechanism includes a positioning block and a plurality of positioning pins. The connecting sleeve is provided with a positioning hole, and the positioning hole and the inner fixing hole are distributed at the preset angle. One end of the positioning block is fixed in the positioning hole by the plurality of positioning pins, and the other end of the positioning block is passed through the guide groove, and the guide groove is arranged parallel to the movement direction of the control rod drive shaft.

7. The control rod clamping structure according to claim 3, characterized in that: The control rod clamping structure also includes an axial compensation mechanism, which includes a spring frame and a spring body. The inner sleeve of the hydraulic cylinder is sleeved on the outside of the inner sleeve, and a positioning sleeve is sleeved between the claw sleeve and the inner sleeve of the hydraulic cylinder; a step is provided on the outside of the inner sleeve, the spring frame is sleeved on the outside of the inner sleeve and located in the positioning sleeve, and the spring frame is arranged between the step and the connecting sleeve; the spring body is press-fitted between the spring frame and the connecting sleeve.

8. The control rod clamping structure according to claim 7, characterized in that: The control rod clamping structure includes a transmission pin claw mechanism and a clamping pin claw mechanism. A first mounting position and a second mounting position are respectively provided on the inner sleeve. The first mounting position is located above the second mounting position. The transmission pin claw mechanism is installed at the first mounting position, and the clamping pin claw mechanism is installed at the second mounting position. The clamping pin claw mechanism is connected to the inner sleeve through the axial compensation mechanism.

9. The control rod clamping structure according to any one of claims 1 to 8, characterized in that: The preset angle does not exceed 60°.

10. An internal control rod drive mechanism, characterized in that: It comprises a lifting hydraulic cylinder, a transmission hydraulic cylinder, a clamping hydraulic cylinder, a limit plug and a control rod clamping structure as claimed in any one of claims 1 to 9, wherein the inner sleeve of the control rod clamping structure is inserted from top to bottom into the axial holes of the lifting hydraulic cylinder, the transmission hydraulic cylinder, the clamping hydraulic cylinder and the limit plug, and the installation positions of the inner sleeve are respectively arranged between the transmission hydraulic cylinder and the clamping hydraulic cylinder, and between the clamping hydraulic cylinder and the limit plug.

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