A wire clamp for electric power equipment

Abstract

The present invention discloses a wire clamp for electric power equipment, specifically relates to the technical field of wire clamps, including a wire clamp body, a pressure plate, a U-shaped locking rod and a hanging plate. The wire clamp body is provided with a placement groove and two symmetrically arranged mounting ears. The top of the wire clamp body is symmetrically provided with four plug holes. The pressure plate is provided with connecting holes with the same number and corresponding positions as the plug holes. The U-shaped locking rod can be plugged into the plug holes and the connecting holes. The present invention sets a deicing mechanism. When the surface of the cable is covered with ice, the wire clamp body will drive the first elastic member and the third elastic member to move downward, and store force on the impact block. When the pressure reaches the pressure threshold of the second elastic member, the impact block is instantly released and hits the cable, thereby deicing the cable, preventing the cable surface from being covered with too much ice, and avoiding the cable from breaking, thereby improving the service life and safety of the cable.

Description

Technical Field

[0001] The present invention relates to the technical field of wire clamps, and more particularly to a wire clamp for electric power equipment. Background Art

[0002] Suspension wire clamps are generally composed of bracket U-bolts, wire clamp hulls made of forgeable cast iron, and pressure plates. Suspension wire clamps are used to fix conductors on insulator strings of straight pole towers, or to suspend lightning arresters on straight pole towers. They can also be used to support transposed conductors on transposed pole towers and fix jumpers on tension corner pole towers.

[0003] However, the existing suspension wire clamps need to disassemble and assemble multiple bolts and nuts, which is troublesome and affects the efficiency of disassembly and assembly. After long-term use, the bolts and nuts may become loose, posing a safety hazard. In addition, during use in winter, ice is easily formed on the surface of the cable, which will increase the weight of the cable, causing the cable to sag or even break, seriously affecting the service life of the cable and posing a major threat to the safe and stable operation of the power grid. Ordinary wire clamps generally cannot solve the problem of icing on the cable surface.

[0004] The present invention provides a wire clamp for electric power equipment, aiming to solve the problems that the wire clamp is troublesome to disassemble and assemble, affecting the disassembly and assembly efficiency, may become loose after long-term use, causing safety hazards, and the cable surface is prone to ice coating, posing a major threat to the safe and stable operation of the power grid. Summary of the invention

[0005] The object of the present invention is to provide a wire clamp for electric power equipment to solve the problems proposed in the above-mentioned background technology that the wire clamp is troublesome to disassemble and assemble, affecting the disassembly and assembly efficiency, may become loose after long-term use, posing a safety hazard, and the cable surface is prone to ice coating, posing a major threat to the safe and stable operation of the power grid.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a wire clamp for electric power equipment, comprising a wire clamp body, a pressure plate, a U-shaped locking rod and a hanging plate, and further comprising: a mounting mechanism, which is arranged on the pressure plate and is used for the quick mounting of the pressure plate and the U-shaped locking rod; a deicing mechanism, which is arranged on the wire clamp body and is used for deicing the cable when ice is covered on the cable surface, the deicing mechanism comprising two symmetrically arranged limit sliders and an impact block; a placement groove and two symmetrically arranged mounting ears are arranged on the wire clamp body, and limit sliding grooves are arranged on the two mounting ears, and the two limit sliding grooves are symmetrically arranged, and the two limit sliding grooves are respectively slidably connected in the corresponding limit sliding grooves, and the two limit sliding blocks are provided with mounting holes;

[0007] The bottom of the wire clamp body is fixedly connected with an installation box, the interior of the installation box is provided with an impact slide groove connected with the placement groove, the impact block is slidably connected in the impact slide groove, the bottoms of the two limiting slide grooves are provided with connecting grooves connected with the impact slide grooves, both sides of the impact block are fixedly connected with mounting plates corresponding to the positions of the two connecting grooves, the two connecting grooves are sleeved with a first elastic member, one end of the two first elastic members are connected to the bottom of the corresponding limiting slider, and the other end of the two first elastic members are connected to the top of the corresponding mounting plate.

[0008] Preferably, two telescopic grooves are symmetrically provided on both sides of the impact block, and limiting columns are slidably connected in the two telescopic grooves. A second elastic member is connected between one end of the two limiting columns located inside the corresponding telescopic grooves and the corresponding telescopic grooves, and the inner wall of the impact slide groove is provided with limiting holes with the same number and corresponding positions as the telescopic grooves.

[0009] Preferably, the ends of the two limiting columns extending out of the corresponding telescopic slots are both set to be semicircular, and can be inserted into the corresponding limiting holes to limit the impact block. When the pressure reaches the pressure threshold of the second elastic member, the limiting column can be squeezed into the telescopic slot by the limiting hole to release the limitation on the impact block.

[0010] Preferably, the bottoms of the two limiting sliding grooves are provided with mounting grooves on both sides of the corresponding connecting grooves, and third elastic members are connected between the bottoms of the two limiting sliding blocks and the corresponding mounting grooves.

[0011] Preferably, four plugging holes are symmetrically formed on the top of the wire clamp body, and connecting holes having the same number and corresponding positions as the plugging holes are formed on the pressure plate, and the U-shaped locking rod can be plugged into the plugging holes and the connecting holes.

[0012] Preferably, the mounting mechanism comprises a plurality of limit blocks, the interior of the pressure plate is provided with extrusion grooves having the same number as the connecting holes and corresponding positions, each of the extrusion grooves is connected to the corresponding connecting hole, and each of the limit blocks is slidably connected in the corresponding extrusion groove.

[0013] Preferably, a fourth elastic member is connected between one end of each of the limiting blocks located inside the corresponding extrusion groove and the corresponding extrusion groove.

[0014] Preferably, a guide groove is provided on the top of each of the limit blocks, and a pressing groove whose number is the same as the extrusion grooves and whose positions correspond to the extrusion grooves is provided on the top of the pressure plate. Two pressing grooves on two extrusion grooves that are opposite to each other form a group, and a pressing plate is slidably connected in each group of the pressing grooves, and the two pressing plates are slidably connected to the corresponding two guide grooves.

[0015] Preferably, the bottom of one end of each limit block extending into the corresponding connecting hole is set as a wedge-shaped surface, and both ends of each U-shaped locking rod are provided with a group of equidistant locking grooves, and the locking grooves can cooperate with the wedge-shaped surface at the bottom of the limit block.

[0016] Preferably, when the U-shaped locking rod is inserted into the connecting hole, the locking groove can squeeze the limit block into the extrusion groove; when the U-shaped locking rod is pulled out of the connecting hole, the limit block can be inserted into the locking groove and limit the U-shaped locking rod; when the pressing plate is pressed, the pressing plate can squeeze the limit block into the extrusion groove through the guide groove, thereby releasing the limit on the U-shaped locking rod.

[0017] Technical effects and advantages of the present invention:

[0018] 1. The present invention provides an installation mechanism so that the locking groove can cooperate with the wedge-shaped surface at the bottom of the limit block during installation, and the limit block can be inserted into the corresponding locking groove and limit the U-shaped locking rod, so that the insertion connection between the pressure plate and the U-shaped locking rod cannot be withdrawn, thereby completing quick installation. When unlocking is required, it is only necessary to press the two pressing plates at the same time so that the bottom of the pressing plate squeezes the corresponding guide groove, thereby squeezing the limit block into the squeezing groove, releasing the limit of the U-shaped locking rod by the limit block, and there is no need to disassemble and assemble multiple bolts and nuts, thereby completing quick unlocking, improving installation efficiency, and preventing loosening after long-term use, thereby improving safety.

[0019] 2. The present invention provides a de-icing mechanism. When the cable surface is covered with ice, the wire clamp body will drive the first elastic member and the third elastic member to move downward and store force on the impact block. When the pressure reaches the pressure threshold of the second elastic member, the impact block is released instantly and hits the cable, thereby de-icing the cable, preventing the cable surface from being covered with excessive ice, and avoiding cable breakage, thereby improving the service life and safety of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 It is a schematic diagram of the installation mechanism structure of the present invention.

[0022] Figure 3 It is a cross-sectional view of the internal structure of the extrusion groove of the present invention.

[0023] Figure 4 It is a schematic diagram of the pressing plate structure of the present invention.

[0024] Figure 5 It is a schematic diagram of the structure of the deicing mechanism of the present invention.

[0025] Figure 6 It is a cross-sectional view of the internal structure of the limiting slide groove of the present invention.

[0026] Figure 7 It is a schematic diagram of the main structure of the wire clamp of the present invention.

[0027] Figure 8 It is a partial structural schematic diagram of the limit sliding block of the present invention.

[0028] Fig. 9 It is a partial structural cross-sectional view of the connecting groove of the present invention.

[0029] Fig.10 It is a cross-sectional view of the internal structure of the installation box of the present invention.

[0030] Fig.11 This is a partial exploded view of the impact block of the present invention.

[0031] The accompanying drawings are marked as follows: 1. wire clamp body; 11. placement groove; 12. mounting ear; 13. plug-in hole; 2. pressure plate; 21. connecting hole; 3. U-shaped locking rod; 4. hanging plate; 5. mounting mechanism; 51. limit block; 52. extrusion groove; 53. fourth elastic member; 54. guide groove; 55. pressing groove; 56. pressing plate; 57. locking groove; 6. de-icing mechanism; 61. limit slider; 62. impact block; 63. limit slide groove; 64. mounting hole; 65. mounting box; 66. impact slide groove; 67. connecting groove; 68. mounting plate; 69. first elastic member; 610. telescopic groove; 611. limit column; 612. second elastic member; 613. limit hole; 614. mounting groove; 615. third elastic member. DETAILED DESCRIPTION

[0032] 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.

[0033] Embodiment 1

[0034] Existing suspension wire clamps require multiple bolts and nuts to be disassembled and assembled, which is troublesome and affects the efficiency of disassembly and assembly. After long-term use, the bolts and nuts may become loose, posing a safety hazard.

[0035] refer to Figure 1 , Figure 4 and Figure 7A wire clamp for electric power equipment according to an embodiment of the present invention comprises a wire clamp body 1, a pressure plate 2, a U-shaped locking rod 3 and a hanging plate 4. A placement groove 11 and two symmetrically arranged mounting ears 12 are arranged on the wire clamp body 1. Four plug holes 13 are symmetrically arranged on the top of the wire clamp body 1. The pressure plate 2 is provided with connecting holes 21 having the same number and corresponding positions as the plug holes 13. The U-shaped locking rod 3 can be plugged into the plug holes 13 and the connecting holes 21.

[0036] refer to Figure 1-Figure 4 , also includes a mounting mechanism 5, which is arranged on the pressing plate 2 and is used for quick installation of the pressing plate 2 and the U-shaped locking rod 3, including a plurality of limit blocks 51, the interior of the pressing plate 2 is provided with extrusion grooves 52 which are the same in number and corresponding in position as the connecting holes 21, each extrusion groove 52 is communicated with the corresponding connecting hole 21, each limit block 51 is slidably connected in the corresponding extrusion groove 52, a fourth elastic member 53 is connected between one end of each limit block 51 located in the corresponding extrusion groove 52 and the corresponding extrusion groove 52, a guide groove 54 is provided on the top of each limit block 51, a pressing groove 55 which is the same in number and corresponding in position as the extrusion groove 52 is provided on the top of the pressing plate 2, two pressing grooves 55 on two extrusion grooves 52 which are away from each other form a group, a pressing plate 56 is slidably connected in each group of pressing grooves 55, and the two pressing plates 56 are slidably connected to the corresponding two guide grooves 54.

[0037] refer to Figure 3 The bottom of one end of each limit block 51 extending into the corresponding connecting hole 21 is set to a wedge-shaped surface, and a group of equidistant locking grooves 57 are opened at both ends of each U-shaped locking rod 3, and the locking grooves 57 can cooperate with the wedge-shaped surface at the bottom of the limit block 51.

[0038] When the U-shaped locking rod 3 is inserted into the connecting hole 21, the locking groove 57 can squeeze the limit block 51 into the extrusion groove 52. When the U-shaped locking rod 3 is pulled out from the connecting hole 21, the limit block 51 can be inserted into the locking groove 57 and limit the U-shaped locking rod 3. When the pressing plate 56 is pressed, the pressing plate 56 can squeeze the limit block 51 into the extrusion groove 52 through the guide groove 54, thereby releasing the limit on the U-shaped locking rod 3.

[0039] During actual use, the cable is placed in the placement groove 11, and then the two U-shaped locking rods 3 are inserted into the corresponding plug-in holes 13, and then the connecting hole 21 of the pressure plate 2 is plugged into the two ends of the corresponding two U-shaped locking rods 3, and the pressure plate 2 is pressed so that the locking grooves 57 of the two U-shaped locking rods 3 are inserted into the corresponding connecting holes 21. In the process of inserting the U-shaped locking rod 3 into the connecting hole 21, the locking groove 57 can cooperate with the wedge-shaped surface at the bottom of the limit block 51, and the locking groove 57 can squeeze the limit block 51 into the extrusion groove 52, which will not affect the plugging of the locking groove 57 and the connecting hole 21.

[0040] When the pressure plate 2 is pressed so that the bottom of the pressure plate 2 contacts the cable surface and cannot move further downward, the limit block 51 can be inserted into the corresponding locking groove 57 and limit the U-shaped locking rod 3, so that the pressure plate 2 and the U-shaped locking rod 3 cannot be pulled out, thereby completing the installation.

[0041] When unlocking is required, the two pressing plates 56 are pressed simultaneously so that the bottom of the pressing plate 56 squeezes the corresponding guide groove 54, thereby squeezing the limit block 51 into the squeezing groove 52, releasing the limit of the limit block 51 on the U-shaped locking rod 3, thereby completing the unlocking. At this time, the pressing plate 2 can be pulled out of the U-shaped locking rod 3.

[0042] To sum up, through the setting of the installation mechanism 5, during installation, the locking groove 57 can cooperate with the wedge-shaped surface at the bottom of the limit block 51, and the limit block 51 can be inserted into the corresponding locking groove 57 and limit the U-shaped locking rod 3, so that the pressure plate 2 and the U-shaped locking rod 3 cannot be pulled out, thereby completing the quick installation. When unlocking is required, it is only necessary to press the two pressing plates 56 at the same time so that the bottom of the pressing plate 56 squeezes the corresponding guide groove 54, thereby squeezing the limit block 51 into the extrusion groove 52, and releasing the limit of the U-shaped locking rod 3 by the limit block 51. There is no need to disassemble and assemble multiple bolts and nuts, thereby completing quick unlocking, improving installation efficiency, and will not loosen after long-term use, thereby improving safety.

[0043] Embodiment 2

[0044] When cables are used in winter, ice easily forms on their surfaces, which increases their weight, causes them to sag, or even break, severely affecting their service life and posing a significant threat to the safe and stable operation of the power grid. Therefore, this embodiment improves the device described in the above embodiment.

[0045] refer to Figure 1 and Figure 5-Figure 11, also includes a deicing mechanism 6, which is arranged on the wire clamp body 1 and is used to de-ice the cable when ice is covered on the cable surface. It includes two symmetrically arranged limit sliders 61 and an impact block 62. When ice is covered on the cable surface, the wire clamp body 1 can store force for the impact block 62 under the limiting action of the two limit sliders 61, and hit the cable with the stored force through the impact block 62. The two mounting ears 12 are both provided with limit slide grooves 63, and the two limit slide grooves 63 are symmetrically arranged. The two limit slide grooves 61 are respectively slidably connected in the corresponding limit slide grooves 63. The two limit slide grooves 61 are both provided with mounting holes 64, and the two mounting holes 64 are used to install the hanging plate 4 through bolts. The bottom of the wire clamp body 1 is fixedly connected with a mounting box 65, and the interior of the mounting box 65 is provided with an impact slide groove 66 connected to the placement groove 11, and the impact block 62 is slidably connected In the impact slide groove 66, the bottom of the two limit slide grooves 63 is provided with a connecting groove 67 connected to the impact slide groove 66, and the two sides of the impact block 62 are fixedly connected with the mounting plates 68 corresponding to the positions of the two connecting grooves 67. The two connecting grooves 67 are sleeved with a first elastic member 69, one end of the two first elastic members 69 is connected to the bottom of the corresponding limit sliding block 61, and the other end of the two first elastic members 69 is connected to the top of the corresponding mounting plate 68. Two telescopic grooves 610 are symmetrically provided on both sides of the impact block 62, and the two telescopic grooves 610 are slidably connected with limiting columns 611, and the two limiting columns 611 are located in The corresponding telescopic groove 610 is connected with a second elastic member 612 between one end and the corresponding telescopic groove 610, and the inner wall of the impact slide groove 66 is provided with limiting holes 613 that are the same in number and corresponding in position as the telescopic grooves 610.

[0046] refer to Fig.10 and Fig.11 The two limiting columns 611 extending out of the corresponding telescopic slots 610 are both set to be semicircular, and can be inserted into the corresponding limiting holes 613 to limit the impact block 62. When the pressure reaches the pressure threshold of the second elastic member 612, the limiting column 611 can be squeezed into the telescopic slot 610 by the limiting hole 613, thereby releasing the limit on the impact block 62.

[0047] refer to Figure 6-Figure 8 The bottoms of the two limiting sliding grooves 63 are provided with mounting grooves 614 on both sides of the corresponding connecting grooves 67 , and third elastic members 615 are connected between the bottoms of the two limiting sliding blocks 61 and the corresponding mounting grooves 614 .

[0048] During actual use, the wire clamp body 1 is installed on the hanging plate 4 by inserting bolts into the installation hole 64. When the cable surface is covered with ice, the weight of the cable will gradually increase, and the weight will act on the wire clamp body 1, so that the wire clamp body 1 moves downward under the limiting action of the limiting slider 61 and the limiting groove 63, and the first elastic member 69 and the third elastic member 615 are gradually stretched. At this time, since the two limiting columns 611 are both inserted into the corresponding limiting holes 613 and limit the impact block 62, the impact block 62 cannot move at this time, and the gradual stretching of the first elastic member 69 can store force for the impact block 62.

[0049] When the pressure reaches the pressure threshold of the second elastic member 612, the limiting column 611 is squeezed into the telescopic slot 610 by the limiting hole 613. At this time, the limiting of the impact block 62 is released, and the impact block 62 is released instantly. After being released, the impact block 62 will hit the cable in the placement slot 11 under the rebound action of the first elastic member 69, thereby de-icing the cable.

[0050] When the ice on the cable surface is removed, the weight of the cable will be reduced, and the third elastic member 615 will shrink, thereby driving the wire clamp body 1 to move upward back to the initial position through the third elastic member 615, and pushing the impact block 62 back to the initial position through the shrinking first elastic member 69, so that the two limit columns 611 are reinserted into the corresponding limit holes 613 to prepare for the next deicing. This reciprocating process can prevent excessive ice on the cable surface, thereby improving the service life and safety of the cable.

[0051] To sum up, through the setting of the de-icing mechanism 6, when the cable surface is covered with ice, the wire clamp body 1 will drive the first elastic member 69 and the third elastic member 615 to move downward, and accumulate force on the impact block 62. When the pressure reaches the pressure threshold of the second elastic member 612, the impact block 62 is released instantly and hits the cable, thereby de-icing the cable, preventing excessive ice from covering the cable surface, and avoiding cable breakage, thereby improving the service life and safety of the cable.

[0052] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wire clamp for electric power equipment, comprising a wire clamp body (1), a pressure plate (2), a U-shaped locking rod (3) and a hanging plate (4), characterized in that: Also includes: A mounting mechanism (5) disposed on the pressing plate (2) and used for quickly mounting the pressing plate (2) and the U-shaped locking rod (3); A deicing mechanism (6) disposed on the cable clamp body (1) and used to de-ice the cable when ice is applied to the cable surface, the deicing mechanism (6) comprising two symmetrically disposed limit sliders (61) and an impact block (62); The wire clamp body (1) is provided with a placement groove (11) and two symmetrically arranged mounting ears (12), the two mounting ears (12) are provided with a limit slide groove (63), the two limit slide grooves (63) are symmetrically arranged, the two limit slide blocks (61) are respectively slidably connected in the corresponding limit slide grooves (63), and the two limit slide blocks (61) are provided with a mounting hole (64); The bottom of the wire clamp body (1) is fixedly connected to a mounting box (65), the interior of the mounting box (65) is provided with an impact slide groove (66) connected to the placement groove (11), the impact block (62) is slidably connected in the impact slide groove (66), the bottoms of the two limit slide grooves (63) are provided with connecting grooves (67) connected to the impact slide grooves (66), both sides of the impact block (62) are fixedly connected with mounting plates (68) corresponding to the positions of the two connecting grooves (67), the two connecting grooves (67) are sleeved with first elastic members (69), one end of the two first elastic members (69) is connected to the bottom of the corresponding limit slide block (61), and the other end of the two first elastic members (69) is connected to the top of the corresponding mounting plate (68).

2. The power equipment wire clamp according to claim 1, characterized in that: Two telescopic grooves (610) are symmetrically provided on both sides of the impact block (62), and limiting pillars (611) are slidably connected in the two telescopic grooves (610). A second elastic member (612) is connected between one end of the two limiting pillars (611) located inside the corresponding telescopic groove (610) and the corresponding telescopic groove (610), and the inner wall of the impact slide groove (66) is provided with limiting holes (613) of the same number and corresponding positions as the telescopic grooves (610).

3. The power equipment wire clamp according to claim 2, characterized in that: One end of each of the two limiting columns (611) extending out of the corresponding telescopic slot (610) is arranged in a semicircular shape and can be inserted into the corresponding limiting hole (613) to limit the impact block (62); when the pressure reaches the pressure threshold of the second elastic member (612), the limiting column (611) can be squeezed into the telescopic slot (610) by the limiting hole (613) to release the limiting of the impact block (62).

4. The power equipment wire clamp according to claim 3, characterized in that: The bottoms of the two limiting sliding grooves (63) are provided with mounting grooves (614) on both sides of the corresponding connecting groove (67), and third elastic members (615) are connected between the bottoms of the two limiting sliding blocks (61) and the corresponding mounting grooves (614).

5. The power equipment wire clamp according to claim 4, characterized in that: The top of the wire clamp body (1) is provided with four plug holes (13) symmetrically arranged one above the other, the pressing plate (2) is provided with connecting holes (21) the same in number as the plug holes (13) and corresponding in position to the connecting holes (13), and the U-shaped locking rod (3) can be plugged into the plug holes (13) and the connecting holes (21).

6. The power equipment wire clamp according to claim 5, characterized in that: The mounting mechanism (5) comprises a plurality of limit blocks (51); the pressing plate (2) is provided with extrusion grooves (52) in the same number as the connection holes (21) and in corresponding positions; each of the extrusion grooves (52) is connected to a corresponding connection hole (21); and each of the limit blocks (51) is slidably connected in a corresponding extrusion groove (52).

7. The power equipment wire clamp according to claim 6, characterized in that: A fourth elastic member (53) is connected between one end of each of the limit blocks (51) located inside the corresponding extrusion groove (52) and the corresponding extrusion groove (52).

8. The power equipment wire clamp according to claim 7, characterized in that: A guide groove (54) is formed on the top of each of the limit blocks (51), and pressing grooves (55) of the same number and corresponding positions as the extrusion grooves (52) are formed on the top of the pressure plate (2). Two pressing grooves (55) on two extrusion grooves (52) that are away from each other form a group. A pressing plate (56) is slidably connected in each group of the pressing grooves (55), and the two pressing plates (56) are slidably connected to the corresponding two guide grooves (54).

9. The power equipment wire clamp according to claim 8, characterized in that: The bottom of one end of each of the limit blocks (51) extending into the corresponding connecting hole (21) is arranged as a wedge-shaped surface, and both ends of each of the U-shaped locking rods (3) are provided with a group of equidistantly arranged locking grooves (57), and the locking grooves (57) can cooperate with the wedge-shaped surface at the bottom of the limit block (51).

10. The power equipment wire clamp according to claim 9, characterized in that: When the U-shaped locking rod (3) is inserted into the connecting hole (21), the locking groove (57) can squeeze the limiting block (51) into the squeezing groove (52); when the U-shaped locking rod (3) is withdrawn from the connecting hole (21), the limiting block (51) can be inserted into the locking groove (57) and limit the U-shaped locking rod (3); when the pressing plate (56) is pressed, the pressing plate (56) can squeeze the limiting block (51) into the squeezing groove (52) through the guide groove (54), thereby releasing the limit on the U-shaped locking rod (3).

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