Calibration device for power cable fault detection
Through the combination of positioning calibration slot, calibration wheel mechanism and gripping assembly, the problem of inaccurate movement in cable fault detection is solved, and the efficiency and accuracy of cable fault detection is achieved, ensuring that the test induction head is always close to the cable, improving detection efficiency and Sensitivity.
Patent Information
- Application Number
- CN202411233046.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2024-12-10
AI Technical Summary
In complex circuits, handheld devices are difficult to move accurately along the cable, resulting in low efficiency and difficulty in detecting power failures, especially in finding fault points where damaged cables are damaged within the wall.
By positioning the calibration groove and calibration wheel mechanism, combining the gripping assembly and the adaptation control assembly, ensure that the detection calibration head moves in a straight line along the cable, the test induction head is always close to the cable, improve detection efficiency, and adapt to different situations through the adjustment mechanism.
It realizes the accuracy and simplicity of operation of cable fault detection, avoids the cable from the positioning groove, and improves detection efficiency and sensitivity.
Smart Images
Figure CN119104970A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of power fault testing, and in particular is a calibration device for power cable fault detection. Background Art
[0002] The smooth flow of wired communications and the transmission of electricity depend on the normal operation of cable lines. Once the lines are blocked, communication failures will occur, resulting in great economic losses and adverse social impacts. Therefore, it is necessary to detect the faults in a timely manner and eliminate them quickly. Among them, cable fault testers are important tools for maintaining various cables.
[0003] The workload of power fault detection is usually large. It is extremely difficult to accurately find the faulty cable in a complex circuit, especially to find the fault point of a damaged cable in a wall. The line patrol device equipped with the fault detection equipment needs to move along the cable until it moves to the fault point and issues an alarm. The reality is that most cables are straight, and it is difficult for handheld devices to move accurately along the cables. This not only reduces the efficiency of fault detection, but also increases the difficulty of fault detection. Therefore, it needs to be improved. Summary of the invention
[0004] In order to solve the problems raised in the above background technology, the present invention provides a calibration device for power cable fault detection, which has the advantages of accurate detection and easy operation.
[0005] Among them, by positioning the calibration slot and the calibration wheel mechanism, it can be ensured that the detection calibration head can be controlled by the gripping head to accurately move in a straight line along the exposed power cable, thereby ensuring that the test sensing head is always as close as possible to the power cable to be tested, thereby improving the detection efficiency.
[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a calibration device for power cable fault detection, comprising a detection and calibration head, a plurality of evenly distributed positioning and calibration grooves are provided at the bottom of the detection and calibration head, three evenly distributed calibration wheel mechanisms are embedded in the bottom of the detection and calibration head, a test sensing head is arranged in the middle of the detection and calibration head, a gripping assembly is arranged at the top of the detection and calibration head, an adaptation control assembly is arranged in the middle of the gripping assembly, the lower end of the adaptation control assembly passes through the gripping assembly and extends to the interior of the detection and calibration head and is connected to the test sensing head, the bottom of the test sensing head is located above the top of the inner cavity of the positioning and calibration groove, two left and right indicator needles are arranged at the top of the detection and calibration head, an operation panel is also arranged at the top of the detection and calibration head, and an adjustment mechanism is arranged inside the detection and calibration head.
[0007] Preferably, the inner diameters of the several positioning calibration grooves are different, and each positioning calibration groove comprises two parts located on both sides of the test sensing head. The two parts are symmetrical relative to the axis of the test sensing head, and the extension lines of the two indicator needles are parallel to one of the positioning calibration grooves.
[0008] Preferably, the inner wall of the positioning and calibration groove is smooth, and the distance between the top of the inner cavity of the positioning and calibration groove and the bottom of the detection and calibration head is smaller than the outer diameter of the power cable adapted by the positioning and calibration groove.
[0009] Preferably, the calibration wheel mechanism includes a mounting groove opened at the bottom of the detection calibration head, a mounting block is movably sleeved inside the mounting groove, a directional roller is movably connected to the bottom of the mounting block, and a connecting slide rod is fixedly connected to the top of the mounting block.
[0010] Preferably, the distance between the top of the mounting block and the bottom of the directional roller is smaller than the depth of the mounting groove, and the directional roller is made of non-slip rubber.
[0011] Preferably, the gripping assembly includes a gripping head arranged on the top of the detection and calibration head, the outer diameter of the upper end of the gripping head is larger than the outer diameter of its lower end, the outer diameter of the lower end of the detection and calibration head is larger than the outer diameter of its upper end, and the outer surfaces of the gripping head and the detection and calibration head are smooth and smoothly connected.
[0012] Preferably, a sliding cavity is provided in the middle of the gripping head and the detection and calibration head, the inner wall of the sliding cavity is smooth, and the test sensing head and the adaptation control assembly are movably installed inside the sliding cavity.
[0013] Preferably, a positioning groove located outside the sliding cavity is provided inside the gripping head, and a rotating retaining ring is movably sleeved inside the positioning groove. The cross-sections of the positioning groove and the rotating retaining ring are both inverted "L-shaped", and the outer surface of the lower end of the rotating retaining ring is movably sleeved with the inner wall of the lower end of the positioning groove. The outer diameter of the upper end of the rotating retaining ring is larger than the inner diameter of the lower end of the positioning groove, and the outer diameter of the upper end of the rotating retaining ring is smaller than the inner diameter of the upper end of the positioning groove; a clockwork spring located outside the rotating retaining ring is provided at the upper end of the inner cavity of the positioning groove, and the two ends of the clockwork spring are respectively connected to the outer surface of the rotating retaining ring and the inner wall of the positioning groove.
[0014] Preferably, the adaptation control component includes a pressure head movably sleeved in the sliding cavity, the sliding cavity is fixedly sleeved with an upper and lower positioning rings, the sliding cavity is movably sleeved with a limit ring located between the upper and lower positioning rings, the limit ring is fixedly sleeved with a limit connecting rod inside the limit ring, the two ends of the limit connecting rod respectively pass through the upper and lower positioning rings, the top of the limit connecting rod is fixedly connected to the pressure head, and the bottom of the limit connecting rod is fixedly connected to the test sensing head; a positioning spring located at the bottom of the pressure head is provided inside the sliding cavity, the positioning spring is located at the top of an upper positioning ring, and the two ends of the positioning spring are respectively connected to the pressure head and the positioning ring.
[0015] Preferably, the adjustment mechanism includes an adjustment ring rotatably clamped on the outside of the detection and calibration head, the detection and calibration head is provided with a limit cavity located outside the sliding cavity, the outer surface of the adjustment ring is provided with a plurality of evenly distributed connecting grooves, the inner sides of the connecting grooves are connected with the limit cavity; the limit cavity and the connecting grooves are respectively slidably clamped with a limit ring and a limit connecting block, the internal thread of the adjustment ring is sleeved with a linkage ring, and the two ends of the limit connecting block are respectively fixedly connected to the limit ring and the linkage ring.
[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Due to the arrangement of the positioning calibration groove and the calibration wheel mechanism, the present invention can ensure that the detection calibration head can be controlled by the gripping head to accurately move in a straight line along the exposed power cable, thereby ensuring that the test sensing head is always as close as possible to the power cable to be tested, thereby improving the detection efficiency.
[0017] 2. Due to the setting of the gripping assembly of the present invention, it can be ensured that when there is no external force, the two gripping heads can maintain a relatively static state with the two indicator needles, thereby making it convenient for the operator to accurately clamp the positioning calibration groove on the exposed power cable. At the same time, when the gripping head is gripped, the elastic deformation of the clockwork spring can prevent the gripping head from accidentally rotating and causing the detection and calibration head to rotate, thereby preventing the power cable from escaping from the positioning calibration groove during movement. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a bottom schematic diagram of the present invention; Figure 3 A bottom view of the present invention; Figure 4 It is a front view of the cross section of the present invention; Figure 5 It is a cross-sectional view of the top of the connecting groove of the present invention.
[0019] In the figure: 1. Detection and calibration head; 2. Positioning and calibration groove; 3. Calibration wheel mechanism; 31. Mounting groove; 32. Mounting block; 33. Orientation roller; 34. Connecting slide rod; 4. Test sensor head; 5. Gripping assembly; 51. Gripping head; 52. Sliding cavity; 53. Positioning groove; 54. Rotating clamp; 55. Spring; 6. Adaptation control assembly; 61. Pressure head; 62. Limit connecting rod; 63. Positioning ring; 64. Limit ring; 65. Positioning spring; 7. Indicator needle; 8. Operation panel; 9. Adjustment mechanism; 91. Adjustment ring; 92. Limit cavity; 93. Connecting groove; 94. Limit ring; 95. Linkage ring; 96. Limit connecting block. DETAILED DESCRIPTION
[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0021] like Figures 1 to 5 As shown, the present invention provides a calibration device for detecting faults of power cables, comprising a detection and calibration head 1, a plurality of evenly distributed positioning and calibration grooves 2 are provided at the bottom of the detection and calibration head 1, three evenly distributed calibration wheel mechanisms 3 are embedded at the bottom of the detection and calibration head 1, a test sensing head 4 is provided at the middle of the detection and calibration head 1, a gripping component 5 is provided at the top of the detection and calibration head 1, an adaption control component 6 is provided at the middle of the gripping component 5, the lower end of the adaption control component 6 penetrates the gripping component 5 and extends to the inside of the detection and calibration head 1 and is connected to the test sensing head 4, the bottom of the test sensing head 4 is located above the top of the inner cavity of the positioning and calibration groove 2, two left and right indicator needles 7 are provided at the top of the detection and calibration head 1, an operation panel 8 is also provided at the top of the detection and calibration head 1, and an adjustment mechanism 9 is provided inside the detection and calibration head 1; Among them, due to the setting of the positioning calibration slot 2 and the calibration wheel mechanism 3, it can be ensured that the detection calibration head 1 can be controlled by the gripping head 51 to move accurately along the straight line of the exposed power cable, thereby ensuring that the test sensor head 4 is always as close as possible to the power cable to be tested, thereby improving the detection efficiency.
[0022] like Figure 2 and Figure 3As shown, the inner diameters of several positioning calibration grooves 2 are different, and each positioning calibration groove 2 includes two parts located on both sides of the test sensing head 4, the two parts are symmetrical relative to the axis of the test sensing head 4, and the extension lines of the two indicator needles 7 are parallel to one of the positioning calibration grooves 2; due to the setting of the two indicator needles 7, the parallel positioning calibration grooves 2 can be accurately stuck on the exposed power cable under the guidance of the two, and then ensure that the test sensing head 4 can move in a straight line along the power cable for connection detection under the restriction of the positioning calibration groove 2.
[0023] like Figure 4 As shown, the inner wall of the positioning and calibration groove 2 is smooth, and the distance between the top of the inner cavity of the positioning and calibration groove 2 and the bottom of the detection and calibration head 1 is smaller than the outer diameter of the power cable adapted by the positioning and calibration groove 2.
[0024] like Figure 3 and Figure 4 As shown, the calibration wheel mechanism 3 includes a mounting groove 31 opened at the bottom of the detection calibration head 1, a mounting block 32 is movably sleeved inside the mounting groove 31, a directional roller 33 is movably connected to the bottom of the mounting block 32, and a connecting slide rod 34 is fixedly connected to the top of the mounting block 32.
[0025] like Figure 4 As shown, the distance between the top of the mounting block 32 and the bottom of the directional roller 33 is smaller than the depth dimension of the mounting groove 31, and the directional roller 33 is made of anti-slip rubber; due to the setting of the mounting groove 31, the bottom of the directional roller 33 can be extended to the outside of the mounting groove 31 through the adjustment mechanism 9, thereby meeting the operational requirements of different situations.
[0026] like Figure 4 As shown, the gripping assembly 5 includes a gripping head 51 arranged on the top of the detection and calibration head 1, the outer diameter of the upper end of the gripping head 51 is larger than the outer diameter of its lower end, and the outer diameter of the lower end of the detection and calibration head 1 is larger than the outer diameter of its upper end, and the outer surfaces of the gripping head 51 and the detection and calibration head 1 are smooth and smoothly connected; due to the setting of the gripping head 51, it is convenient for the operator to control the movement of the detection and calibration head 1.
[0027] like Figure 4 As shown, a sliding cavity 52 is provided in the middle of the gripping head 51 and the detection and calibration head 1 . The inner wall of the sliding cavity 52 is smooth. The test sensing head 4 and the adaptation control assembly 6 are both movably installed inside the sliding cavity 52 .
[0028] like Figure 4As shown, a positioning groove 53 located outside the sliding cavity 52 is provided inside the gripping head 51, and a rotating snap ring 54 is movably sleeved inside the positioning groove 53. The cross-sections of the positioning groove 53 and the rotating snap ring 54 are both inverted "L-shaped". The outer surface of the lower end of the rotating snap ring 54 is movably sleeved with the inner wall of the lower end of the positioning groove 53. The outer diameter of the upper end of the rotating snap ring 54 is larger than the inner diameter of the lower end of the positioning groove 53, and the outer diameter of the upper end of the rotating snap ring 54 is smaller than the inner diameter of the upper end of the positioning groove 53. A spring 55 located outside the rotating snap ring 54 is provided at the upper end of the inner cavity of the positioning groove 53, and the two ends of the spring 55 are respectively connected to the outer surface of the rotating snap ring 54 and the inner wall of the positioning groove 53. Among them, due to the setting of the gripping assembly 5, it can be ensured that when there is no external force, the two gripping heads 51 can maintain a relatively static state with the two indicator needles 7, so that it is convenient for the operator to accurately clamp the positioning calibration groove 2 on the exposed power cable. At the same time, when the gripping head 51 is gripped, with the elastic deformation of the rotating clamp 54, the gripping head 51 can be prevented from accidentally rotating, causing the detection and calibration head 1 to rotate, thereby preventing the power cable from escaping from the positioning calibration groove 2 during movement.
[0029] like Figure 4 As shown, the adaptor control assembly 6 includes a pressure head 61 movably sleeved in the interior of the sliding cavity 52, and the interior of the sliding cavity 52 is fixedly sleeved with two upper and lower positioning rings 63, and the interior of the sliding cavity 52 is movably sleeved with a limit ring 64 located between the upper and lower positioning rings 63, and the interior of the limit ring 64 is fixedly sleeved with a limit connecting rod 62, and the two ends of the limit connecting rod 62 respectively penetrate the upper and lower positioning rings 63, and the top of the limit connecting rod 62 is fixedly connected to the pressure head 61, and the bottom of the limit connecting rod 62 is fixedly connected to the test sensor head 4; the interior of the sliding cavity 52 is provided with a pressure head 61, and the pressure head 61 is fixedly connected to the bottom of the limit connecting rod 62. The positioning spring 65 at the bottom of the test sensor head 4 is located at the top of a positioning ring 63 above, and the two ends of the positioning spring 65 are connected to the pressure head 61 and the positioning ring 63 respectively; due to the arrangement of the two positioning rings 63, it can be convenient to ensure that when the bottom of the test sensor head 4 rises to the highest point, it can be as close to the top of the inner cavity of the positioning calibration groove 2 as possible, and when it falls to the lowest point, it can be as close to the horizontal plane where the bottom of the directional roller 33 is located as possible, so that the bottom of the test sensor head 4 can always be as close to the power cable to be tested as possible, thereby improving the detection sensitivity.
[0030] like Figure 4 and Figure 5As shown, the adjustment mechanism 9 includes an adjustment ring 91 rotatably clamped on the outside of the detection and calibration head 1, a limit cavity 92 located on the outside of the sliding cavity 52 is provided inside the detection and calibration head 1, and a plurality of evenly distributed connecting grooves 93 are provided on the outer surface of the adjustment ring 91, and the inner side of the connecting groove 93 is connected with the limit cavity 92; a limit ring 94 and a limit connecting block 96 are respectively slidably clamped inside the limit cavity 92 and the connecting groove 93, and a linkage ring 95 is connected to the inner thread of the adjustment ring 91, and the two ends of the limit connecting block 96 are respectively fixedly connected to the limit ring 94 and the linkage ring 95.
[0031] The working principle and use process of the present invention: When performing fault detection on an exposed power cable, the gripping head 51 is held and the movement of the detection calibration head 1 is controlled so that the positioning calibration groove 2 of a suitable size is stuck on the surface of the power cable. At this time, the test sensing head 4 can be as close to the power cable as possible, and then the gripping head 51 is moved along the direction of the power cable to make the test sensing head 4 move axially along the surface of the power cable, thereby performing fault detection on the entire power cable; When fault detection is performed on the power cable in the pre-buried wall, the adjusting ring 91 is rotated to drive the linkage ring 95 to move under the restriction of the detection and calibration head 1, and then the adjusting ring 91 drives the linkage ring 95 to move downward under the restriction of the connecting groove 93 and the limit connection block 96 on the linkage ring 95, and the limit connection block 96 drives the limit ring 94 to move downward, and then the directional roller 33 is pushed to move downward along the inside of the installation groove 31 through the connecting slide bar 34 and the installation block 32 until the bottom of the directional roller 33 moves to below the bottom surface of the detection and calibration head 1, and then the pressure head 61 is pressed while the gripping head 51 is tightened. Since the movement of the pressure head 61 can be With the cooperation of the ring 63 and the limit ring 64, the pressure head 61 pushes the test sensor head 4 downward through the limit connecting rod 62, so that the bottom of the test sensor head 4 is as close as possible to the horizontal plane where the bottom surface of the directional roller 33 is located. Then, the bottom of the directional roller 33 is pressed against the wall by holding the head 51 and the detection and calibration head 1, and the extension lines of the two indicator needles 7 are parallel to the power cable to be tested in the wall, so that the test sensor head 4 can be as close as possible to the power cable pre-buried in the wall. Then, the detection and calibration head 1 can be moved by holding the head 51, and with the cooperation of the three directional rollers 33, the detection and calibration head 1 can be moved as a whole along the power cable pre-buried in the wall.
[0032] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0033] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A calibration device for power cable fault detection, comprising a detection calibration head (1), characterized in that: The bottom of the detection and calibration head (1) is provided with a plurality of evenly distributed positioning and calibration grooves (2), the bottom of the detection and calibration head (1) is embedded with three evenly distributed calibration wheel mechanisms (3), the middle of the detection and calibration head (1) is provided with a test sensing head (4), the top of the detection and calibration head (1) is provided with a gripping assembly (5), the middle of the gripping assembly (5) is provided with an adaption control assembly (6), the lower end of the adaption control assembly (6) passes through the gripping assembly (5) and extends to the inside of the detection and calibration head (1) and is connected to the test sensing head (4), the bottom of the test sensing head (4) is located above the top of the inner cavity of the positioning and calibration groove (2), the top of the detection and calibration head (1) is provided with two left and right indicator needles (7), the top of the detection and calibration head (1) is also provided with an operation panel (8), and the inside of the detection and calibration head (1) is provided with an adjustment mechanism (9).
2. A calibration device for power cable fault detection according to claim 1, characterized in that: The inner diameters of the plurality of positioning calibration grooves (2) are different. Each positioning calibration groove (2) comprises two parts located on both sides of the test sensing head (4). The two parts are symmetrical with respect to the axis of the test sensing head (4). The extension lines of the two indicator needles (7) are parallel to one of the positioning calibration grooves (2).
3. A calibration device for power cable fault detection according to claim 1, characterized in that: The inner wall of the positioning calibration groove (2) is smooth, and the distance between the top of the inner cavity of the positioning calibration groove (2) and the bottom of the detection calibration head (1) is smaller than the outer diameter of the power cable adapted by the positioning calibration groove (2).
4. A calibration device for power cable fault detection according to claim 1, characterized in that: The calibration wheel mechanism (3) comprises a mounting groove (31) provided at the bottom of the detection calibration head (1); a mounting block (32) is movably sleeved inside the mounting groove (31); a directional roller (33) is movably connected to the bottom of the mounting block (32); and a connecting slide rod (34) is fixedly connected to the top of the mounting block (32).
5. A calibration device for power cable fault detection according to claim 4, characterized in that: The distance between the top of the mounting block (32) and the bottom of the directional roller (33) is smaller than the depth dimension of the mounting groove (31), and the directional roller (33) is made of anti-slip rubber.
6. A calibration device for power cable fault detection according to claim 1, characterized in that: The gripping assembly (5) comprises a gripping head (51) arranged on the top of the detection and calibration head (1); the outer diameter of the upper end of the gripping head (51) is greater than the outer diameter of its lower end; the outer diameter of the lower end of the detection and calibration head (1) is greater than the outer diameter of its upper end; and the outer surfaces of the gripping head (51) and the detection and calibration head (1) are both smooth and smoothly connected.
7. A calibration device for power cable fault detection according to claim 6, characterized in that: A sliding cavity (52) is provided in the middle of the gripping head (51) and the detection and calibration head (1); the inner wall of the sliding cavity (52) is smooth; and the test sensing head (4) and the adaptation control component (6) are movably mounted inside the sliding cavity (52).
8. A calibration device for power cable fault detection according to claim 6, characterized in that: The gripping head (51) is provided with a positioning groove (53) located outside the sliding cavity (52), and a rotating snap ring (54) is movably sleeved inside the positioning groove (53). The cross-sections of the positioning groove (53) and the rotating snap ring (54) are both inverted "L-shaped". The outer surface of the lower end of the rotating snap ring (54) is movably sleeved with the inner wall of the lower end of the positioning groove (53). The outer diameter of the upper end of the rotating snap ring (54) is larger than the inner diameter of the lower end of the positioning groove (53), and the outer diameter of the upper end of the rotating snap ring (54) is smaller than the inner diameter of the upper end of the positioning groove (53). The upper end of the inner cavity of the positioning groove (53) is provided with a spring (55) located outside the rotating snap ring (54), and the two ends of the spring (55) are respectively connected to the outer surface of the rotating snap ring (54) and the inner wall of the positioning groove (53).
9. A calibration device for power cable fault detection according to claim 7, characterized in that: The adaptor control assembly (6) comprises a pressure head (61) movably sleeved inside the sliding cavity (52); two upper and lower positioning rings (63) are fixedly sleeved inside the sliding cavity (52); a limit ring (64) located between the upper and lower positioning rings (63) is movably sleeved inside the sliding cavity (52); a limit connecting rod (62) is fixedly sleeved inside the limit ring (64); two ends of the limit connecting rod (62) respectively penetrate the upper and lower positioning rings (63); the top of the limit connecting rod (62) is fixedly connected to the pressure head (61); and the bottom of the limit connecting rod (62) is fixedly connected to the test sensor head (4); a positioning spring (65) is provided inside the sliding cavity (52) and is located at the bottom of the pressure head (61); the positioning spring (65) is located at the top of an upper positioning ring (63); and the two ends of the positioning spring (65) are respectively connected to the pressure head (61) and the positioning ring (63).
10. A calibration device for power cable fault detection according to claim 7, characterized in that: The adjustment mechanism (9) comprises an adjustment ring (91) rotatably engaged with the outside of the detection and calibration head (1); a limit cavity (92) located outside the sliding cavity (52) is provided inside the detection and calibration head (1); a plurality of evenly distributed communication grooves (93) are provided on the outer surface of the adjustment ring (91); the inner sides of the communication grooves (93) are connected with the limit cavity (92); a limit ring (94) and a limit connecting block (96) are respectively slidably engaged inside the limit cavity (92) and the communication grooves (93); a linkage ring (95) is threadedly sleeved inside the adjustment ring (91); and two ends of the limit connecting block (96) are respectively fixedly connected with the limit ring (94) and the linkage ring (95).