Automatic robot wire taking and fixing device

Abstract

The invention discloses an automatic robot wire taking and fixing device, and relates to the field of wire taking and fixing, the automatic robot wire taking and fixing device comprises a position changing component, the position changing component comprises a supporting broken rail, fixing components used for limiting the position of a sky rail wire trolley are fixedly installed on the two sides of the middle of the supporting broken rail, and each fixing component comprises a fixing shell; a detection component used for detecting the position of the sky rail wire trolley is arranged in the fixed shell, a positioning component used for limiting a sky rail wire trolley pulley is further arranged in the fixed component, and the detection component and the positioning component are arranged, so that when the device is used, the detection component can automatically detect the position of the sky rail wire trolley; when the two sets of idler wheels of the sky rail wire trolley move to the designated positions, the locating component can locate and lock the idler wheels of the sky rail wire trolley, unloading failure caused by deviation between the stopping position of the sky rail wire trolley and the mechanical arm is prevented, deviation caused by gravity center shifting can be prevented, and it is guaranteed that the unloading process is stable and reliable.

Description

Technical Field

[0001] This invention relates to the field of wire picking and fixing, specifically to an automatic robot wire picking and fixing device. Background Technology

[0002] In the fiber and textile industries, the inspection, transfer, and unloading processes after the yarn cakes are wound are crucial for ensuring product quality and production efficiency. To achieve automated transfer and multi-process integration of yarn cakes, ceiling-mounted yarn carts, as highly efficient transportation equipment, are widely used in factory production. Relying on pre-installed ceiling tracks, they enable full-process movement and can accurately transfer wound yarn cakes to multiple institutions such as appearance inspection, weight inspection, and tension inspection. After completing inspection and subsequent processing, qualified yarn cakes are transferred to designated unloading positions, where robotic arms perform automated unloading operations, thus constructing an integrated automated production line of "transfer-inspection-unloading".

[0003] Existing overhead wire trolleys typically employ a dual-sided loading structure, capable of simultaneously carrying multiple sets of wire cakes to improve single-transfer efficiency and reduce equipment recursion frequency. The corresponding unloading process is as follows: the robotic arm first aligns with the wire cakes on one side of the overhead wire trolley, sequentially completing the grabbing and unloading operations; after all the wire cakes on one side are unloaded, the overhead wire trolley rotates half a turn via its built-in drive mechanism, aligning the workstation for the other side's wire cake loading with the robotic arm, which then performs the unloading operation on the other side, thereby completing the unloading of the entire trolley of wire cakes.

[0004] However, the above-mentioned unloading method has obvious technical defects in practical applications. Because the yarn cake itself has a certain weight, the center of gravity of the overhead track yarn cart in the double-sided loading state is in a relatively balanced position, and it can maintain stability thanks to the limiting structure of the overhead track. However, when the yarn cake on one side is completely unloaded, the weight distribution of the overhead track yarn cart is disrupted, and the center of gravity shifts significantly towards the unloaded side, causing a change in the force state between the overhead track yarn cart and the overhead track. At this time, when the overhead track yarn cart rotates half a circle, the shifted center of gravity generates a lateral torque, causing the overhead track yarn cart to shift horizontally along the overhead track, making it impossible to accurately maintain the preset rotation center.

[0005] Positional misalignment can trigger a series of chain problems: the robotic arm has been pre-set with the alignment parameters for secondary unloading. If the position of the wire carriage is misaligned, the alignment between the robotic arm and the wire cake on the other side will be inaccurate. At best, it will require recalibration and reduce unloading efficiency. At worst, it may cause the robotic arm to collide with the wire cake when it is grasping, resulting in damage and deformation of the wire cake and affecting the product qualification rate. At the same time, positional misalignment will also increase the frictional wear between the overhead wire carriage and the track, shorten the service life of the equipment, and increase maintenance costs.

[0006] Currently, there is no effective solution to this problem in the industry. Existing overhead wire guide carriages mostly rely on track limiting structures to passively resist center of gravity shift, which cannot fundamentally solve the positional shift problem during rotation. Therefore, there is an urgent need for a wire picking and fixing device that is compatible with existing automated production lines to mitigate the impact of center of gravity shift after unilateral unloading, ensure the positional stability of the overhead wire guide carriage during rotation, support the accuracy of subsequent unloading operations, and meet the industry's dual requirements for production efficiency and product quality. Summary of the Invention

[0007] The purpose of this invention is to provide an automatic robot for picking and fixing silk, so as to solve the problems mentioned in the background art.

[0008] An automatic robot wire-picking and fixing device includes a switching component. The switching component includes a supporting broken rail. Fixing components for limiting the position of the overhead wire carriage are fixedly installed on both sides of the middle part of the supporting broken rail. The fixing component includes a fixing shell. The fixing shell is provided with a detection component for detecting the position of the overhead wire carriage. The fixing component is also provided with a positioning component for limiting the pulleys of the overhead wire carriage. The detection component includes a connecting rod, with sliding baffles on both sides of the lower part of the connecting rod. A connecting bracket is fixedly installed on the upper surface of the sliding baffle. A matching slider is slidably installed inside both ends of the connecting rod. The end of the connecting bracket away from the sliding baffle is rotatably installed in the middle of the matching slider. The sliding baffle has a straight inclined surface. A first sealing cavity is provided in the lower middle part of the connecting rod. A first piston is slidably installed inside the first sealing cavity. A central rotating frame is fixedly installed on the upper surface of the first piston. The central rotating frame is hinged to the middle of the connecting rod. A first spring is fixedly connected between both ends of the connecting rod and the fixed housing.

[0009] Furthermore, the positioning component includes a sliding link, and positioning slide plates are fixedly installed on both sides of the lower part of the sliding link. The sliding link and 432 are slidably installed inside the fixed housing. The positioning slide plates have limiting grooves. A second sealing cavity is provided in the lower middle part of the sliding link. A second piston is slidably locked inside the second sealing cavity. The second piston is fixedly connected to the sliding link. A plurality of evenly distributed second springs are fixedly connected between the sliding link and the fixed housing.

[0010] Furthermore, the interior of the second sealing cavity is filled with hydraulic oil, and a connecting pipe for transmitting hydraulic oil is connected between the second sealing cavity and the first sealing cavity.

[0011] Furthermore, safety components are provided on both sides of the fixed component. Each safety component includes a safety housing, a mating slider is slidably installed inside the safety housing, an L-shaped baffle is provided on the side of the safety housing away from the fixed component, a safety stop bar is rotatably installed on the side of the safety housing near the fixed component, a changing slider is slidably installed inside the safety housing, a shifting stop bar is fixedly installed at the lower end of the safety stop bar, a torsion spring is fixedly connected between the safety stop bar and the safety housing, the changing slider has a helical inclined surface, a connecting slide rod is fixedly connected between the changing slider and the mating slider, and multiple evenly distributed return springs are fixedly installed between the mating slider and the safety housing.

[0012] Furthermore, both sides of the switching component are provided with transport rails for guiding the overhead wire carriage, and the L-shaped baffle is fixedly installed on the transport rails.

[0013] Furthermore, a plurality of evenly distributed drive cylinders are fixedly mounted on the upper surface of the switching component, and the telescopic ends of the drive cylinders are fixedly connected to the fixed component.

[0014] Furthermore, a shifting motor is fixedly installed in the middle of the upper surface of the shifting component. The shifting motor is fixedly installed on the ceiling of the external factory building via a bracket. Multiple connecting brackets are fixedly installed on the upper surface of the shifting component, and the connecting brackets are slidably connected to the ceiling of the external factory building.

[0015] Furthermore, a lifting component for supporting the overhead wire car is provided below the switching component. The lifting component includes a lifting cylinder, and a support platform is rotatably mounted on the telescopic end of the lifting cylinder. Multiple evenly distributed guide brackets are fixedly mounted on the upper surface of the support platform.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. This device is equipped with detection and positioning components. During use, the detection component can automatically detect the position of the overhead wire car. When both sets of rollers of the overhead wire car have moved to the designated position, the positioning component will position and lock the rollers of the overhead wire car to prevent the stopping position of the overhead wire car from deviating from the robotic arm, which would lead to unloading failure. It can also prevent deviation caused by the center of gravity shift, ensuring that the unloading process is stable and reliable. 2. By incorporating a safety component, when the overhead wire car is changing sides, the safety stop lever automatically resets under the action of the torsion spring. The extended safety stop lever can fix the overhead wire car on the broken support rail, preventing it from tipping over and falling due to the misalignment of the broken support rail and the transport overhead wire rail during rotation, thus further ensuring operational safety. Attached Figure Description

[0017] Figure 1This is a schematic diagram of the connection structure between the present invention and the existing technology of the overhead wire car; Figure 2 This is a schematic diagram of the transposition component in this invention; Figure 3 This is a schematic diagram of the structure supporting the broken rail and the connecting bracket in this invention; Figure 4 This is a schematic diagram of the structure of the fixing component in this invention; Figure 5 This is a schematic diagram of the detection component in this invention; Figure 6 This is a schematic diagram of the positioning component in this invention; Figure 7 This is a schematic diagram of the structure of the safety component in this invention; Figure 8 This is a schematic diagram of the lifting component in this invention.

[0018] In the diagram: 1. Transposition component; 2. Lifting component; 3. Transport rail; 4. Fixing component; 5. Safety component; 11. Support for broken rail; 12. First connecting bracket; 13. Drive cylinder; 14. Transposition motor; 21. Lifting cylinder; 22. Support platform; 23. Guide bracket; 41. Fixed housing; 42. Detection component; 43. Positioning component; 51. Safety housing; 52. First mating slider; 53. L-shaped baffle; 54. Safety stop bar; 55. Changing slider; 56. Connecting slide bar 57. Return spring; 421. Connecting rotating rod; 422. Sliding baffle; 423. Second connecting bracket; 424. Second mating slider; 425. First sealing cavity; 426. First piston; 427. Central rotating frame; 428. First spring; 429. Connecting pipe; 420. Straight inclined surface; 431. Sliding connecting rod; 432. Positioning slide plate; 433. Limiting groove; 434. Second sealing cavity; 435. Second piston; 436. Second spring; 541. Shifting stop. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figure 1-8This invention provides a technical solution for an automatic robot wire-retrieving and fixing device: It includes a shifting component 1, which includes a supporting broken rail 11. Fixing components 4 for limiting the position of the overhead wire carriage are fixedly installed on both sides of the middle portion of the supporting broken rail 11. Each fixing component 4 includes a fixing housing 41. Inside the fixing housing 41 is a detection component 42 for detecting the position of the overhead wire carriage. Inside the fixing component 4 is also a positioning component 43 for limiting the pulleys of the overhead wire carriage. Below the shifting component 1 is a lifting component 2 for supporting the overhead wire carriage. Component 2 includes a lifting cylinder 21, with a support platform 22 rotatably mounted on the telescopic end of the lifting cylinder 21. Multiple evenly distributed guide brackets 23 are fixedly mounted on the upper surface of the support platform 22. Both sides of the shifting component 1 are provided with transport rails 3 for guiding the overhead wire car. A shifting motor 14 is fixedly mounted in the middle of the upper surface of the shifting component 1. The shifting motor 14 is fixedly mounted on the ceiling of the external factory building through brackets. Multiple first connecting brackets 12 are fixedly mounted on the upper surface of the shifting component 1. The first connecting brackets 12 are slidably connected to the ceiling of the external factory building.

[0021] The overhead wire trolley is used to transport the wound wire cake to various testing institutions for testing and processing. The overhead wire trolley moves along the overhead rails pre-installed on the factory ceiling. After the testing and processing are completed, the overhead wire trolley will transport the wire cake to the unloading position, and the robotic arm will remove the wire cake from the overhead wire trolley. In actual operation, the overhead wire trolley moves along the transport overhead rail 3 to the switching component 1. At this time, the overhead wire trolley is supported by the support rail 11. The control lifting cylinder 21 works to drive the support platform 22 to rise until the support platform 22 supports the base of the overhead wire trolley. The guide bracket 23 is used to ensure that the overhead wire trolley is kept in the middle of the upper surface of the support platform 22. The lifting component 2 is used to share the overall weight of the overhead wire trolley and prevent the switching component 1 from being damaged due to long-term load. When the overhead wire trolley enters the switching component 1, the detection component 42 will detect the position of the overhead wire trolley in real time. When it is confirmed that it has reached the designated position, the positioning component 43 in the fixing component 4 will start to position and limit the pulley of the overhead wire trolley to prevent it from shifting during the wire picking process. When the robotic arm removes all the wire cakes on one side, the lifting cylinder 21 is lowered to separate the base of the overhead wire carriage from the guide bracket 23. Then, the shifting motor 14 is controlled to rotate the support rail 11 half a turn, rotating the side of the overhead wire carriage with the wire cakes to the robotic arm's working position. Subsequently, the lifting cylinder 21 rises again to make the base contact the guide bracket 23 to complete the secondary bearing.

[0022] The detection component 42 includes a connecting rod 421. Sliding baffles 422 are provided on both sides of the lower part of the connecting rod 421. A second connecting bracket 423 is fixedly installed on the upper surface of the sliding baffles 422. Second mating sliders 424 are slidably installed inside both ends of the connecting rod 421. The end of the second connecting bracket 423 away from the sliding baffles 422 is rotatably installed in the middle of the second mating sliders 424. The sliding baffles 422 have a straight inclined surface 420. A first sealing cavity 425 is provided in the lower middle part of the connecting rod 421. A first piston 426 is slidably installed inside the first sealing cavity 425. A central rotating frame 427 is fixedly installed on the upper surface of the first piston 426. The central rotating frame 427 is hinged to the middle part of the connecting rod 421. A first spring 428 is fixedly connected between both ends of the connecting rod 421 and the fixed housing 41.

[0023] When the overhead wire car first enters the area of ​​the switching component 1, a set of rollers on the overhead wire car first contacts the sliding baffle 422. Due to the inclined surface design of the straight inclined surface 420, the rollers push the sliding baffle 422 upward as they pass. At this time, the second connecting bracket 423 pushes the second mating slider 424 upward. The interior of the first sealing cavity 425 has a suction effect on the central rotating frame 427, causing the central rotating frame 427 not to rise. At this time, the second mating slider 424 will rotate around the central rotating frame 427. When the first set of rollers of the overhead wire car passes the first sliding baffle 422, under the reset action of the first spring 428, the connecting rod 421 will rotate back to its original position until both sets of rollers of the overhead wire car are in contact with the sliding baffle 422. The two sliding baffles 422 are driven to rise synchronously. Because the sliding baffle 422 cannot rotate, the central rotating frame 427 is driven to rise synchronously, and negative pressure is generated inside the first sealing cavity 425.

[0024] The positioning component 43 includes a sliding link 431, and positioning slide plates 432 are fixedly installed on both sides of the lower part of the sliding link 431. The sliding link 431 and the positioning slide plates 432 are slidably installed inside the fixed housing 41. The positioning slide plates 432 have limiting grooves 433. A second sealing cavity 434 is provided in the lower middle part of the sliding link 431. A second piston 435 is slidably locked inside the second sealing cavity 434. The second piston 435 is fixedly connected to the sliding link 431. A plurality of evenly distributed second springs 436 are fixedly connected between the sliding link 431 and the fixed housing 41. The second sealing cavity 434 is filled with hydraulic oil. A connecting pipe 429 for transmitting hydraulic oil is connected between the second sealing cavity 434 and the first sealing cavity 425. A plurality of evenly distributed drive cylinders 13 are fixedly installed on the upper surface of the shifting component 1. The telescopic ends of the drive cylinders 13 are fixedly connected to the fixed component 4.

[0025] When a negative pressure is generated inside the first sealing chamber 425, hydraulic oil is drawn in through the connecting pipe 429. At this time, the second piston 435 will be driven to descend, which in turn will drive the sliding link 431 to descend synchronously. The sliding link 431 will drive the two positioning slide plates 432 to descend synchronously. The limiting groove 433 on the positioning slide plate 432 descends and locks the roller on the overhead wire car. The limiting groove 433 is designed in an arc shape, so if the position of the overhead wire car is slightly deviated, it can still be automatically guided to the correct position under the action of the limiting groove 433, which makes it easy for the robot arm to grab the wire cake on it. At the same time, the second spring 436 is compressed when the sliding link 431 descends. The limiting groove 433 can not only accurately position the overhead wire car, but also provide buffer protection under the action of the hydraulic system to prevent the overhead wire car from deviating under the gripping action of the robot arm, which would lead to inaccurate gripping and positioning in the next time. When the robotic arm removes all the wire cakes, the drive cylinder 13 starts and lifts the entire fixed component 4. At this time, the sliding baffle 422 loses the pressure of the rollers. Under the action of the first spring 428 and the second spring 436, the hydraulic oil gradually flows back from the first sealing chamber 425 to the second sealing chamber 434. The second piston 435 rises and resets, driving the sliding connecting rod 431 and the positioning slide plate 432 to rise as a whole. The limiting groove 433 disengages from the rollers, releasing the limit on the overhead wire car, and thus the overhead wire car can be controlled to move out of the working area.

[0026] Safety components 5 are provided on both sides of the fixed component 4. Each safety component 5 includes a safety housing 51. A first mating slider 52 is slidably installed inside the safety housing 51. An L-shaped baffle 53 is provided on the side of the safety housing 51 away from the fixed component 4. The L-shaped baffle 53 is fixedly installed on the transport rail 3. A safety stop bar 54 is rotatably installed on the side of the safety housing 51 close to the fixed component 4. A changing slider 55 is slidably installed inside the safety housing 51. A shifting stop bar 541 is fixedly installed at the lower end of the safety stop bar 54. A torsion spring is fixedly connected between the safety stop bar 54 and the safety housing 51. The changing slider 55 has a helical inclined surface. A connecting slide bar 56 is fixedly connected between the changing slider 55 and the first mating slider 52. Multiple evenly distributed return springs 57 are fixedly installed between the first mating slider 52 and the safety housing 51.

[0027] After the robotic arm removes all the wire cakes from one side of the overhead wire carriage, the shifting motor 14 will drive the supporting broken rail 11 to rotate. The supporting broken rail 11 will drive the overhead wire carriage on it to rotate synchronously, so as to rotate the wire cakes on the other side to a position that the robotic arm can grasp. Because the center of gravity of the overhead wire carriage will shift after all the wire cakes on one side are removed, when the shifting motor 14 drives the supporting broken rail 11 to rotate, the shifted center of gravity will cause the overhead wire carriage to sway or even overturn. Especially when there is a gap between the rotation of the supporting broken rail 11 and the transport overhead rail 3, if a shift occurs, the overhead wire carriage may fall off the supporting broken rail 11 and cause a serious safety accident. When the supporting broken rail 11 and the transport ceiling rail 3 are on the same horizontal plane, the first mating slider 52 is pushed into the interior of the safety housing 51 by the L-shaped baffle 53. At this time, the first mating slider 52 drives the changing slider 55 to move synchronously through the connecting slide rod 56. Then, the spiral inclined surface of the changing slider 55 contacts the shifting stop 541, changing the position of the shifting stop 541 from horizontal to vertical. At this time, the torsion spring is compressed. When the supporting broken rail 11 rotates and is misaligned with the transport ceiling rail 3, the first mating slider 52 is ejected under the action of the return spring 57. The first mating slider 52 drives the changing slider 55 through the connecting slide rod 56. 5. When the slider 55 moves synchronously, it loses its function of interchanging the shifting lever 541. Under the action of the torsion spring, the safety lever 54 will rotate from the vertical state to the horizontal state. At this time, the safety lever 54 will block the top of the overhead wire car, achieving the safety effect and preventing the overhead wire car from overturning due to the shift of the center of gravity during rotation, effectively ensuring the safety of equipment and personnel. When the support rail 11 rotates half a turn, the inclined surface on the first mating slider 52 can be pushed back into the safety housing 51 by the L-shaped baffle 53. After all the wire cakes on both sides are removed, it rotates half a turn again, so that the device returns to the initial position, which facilitates the movement of the overhead wire car.

[0028] The above are merely preferred embodiments of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concept, should be covered within the scope of protection of the present invention.

Claims

1. An automatic robot wire-retrieving and fixing device, comprising a transposition component (1), characterized in that: The switching component (1) includes a supporting broken rail (11). Both sides of the middle part of the supporting broken rail (11) are fixedly installed with fixing components (4) for limiting the position of the overhead track car. The fixing component (4) includes a fixing housing (41). The fixing housing (41) is provided with a detection component (42) for detecting the position of the overhead track car. The fixing component (4) is also provided with a positioning component (43) for limiting the pulley of the overhead track car. The detection component (42) includes a connecting rod (421), with sliding baffles (422) on both sides below the connecting rod (421). A second connecting bracket (423) is fixedly installed on the upper surface of the sliding baffle (422). A second mating slider (424) is slidably installed inside both ends of the connecting rod (421). The end of the second connecting bracket (423) away from the sliding baffle (422) is rotatably installed in the middle of the second mating slider (424). 22) has a straight inclined surface (420), and a first sealing cavity (425) is provided in the lower middle part of the connecting rod (421). A first piston (426) is slidably installed inside the first sealing cavity (425). A central rotating frame (427) is fixedly installed on the upper surface of the first piston (426). The central rotating frame (427) is hinged to the middle part of the connecting rod (421). A first spring (428) is fixedly connected between both ends of the connecting rod (421) and the fixed housing (41).

2. The automatic robot wire-retrieving and fixing device according to claim 1, characterized in that: The positioning component (43) includes a sliding link (431), and positioning slide plates (432) are fixedly installed on both sides of the lower part of the sliding link (431). The sliding link (431) and the positioning slide plates (432) are slidably installed inside the fixed housing (41). The positioning slide plates (432) have limiting grooves (433). A second sealing cavity (434) is provided in the lower middle part of the sliding link (431). A second piston (435) is slidably installed inside the second sealing cavity (434). The second piston (435) is fixedly connected to the sliding link (431). A plurality of evenly distributed second springs (436) are fixedly connected between the sliding link (431) and the fixed housing (41).

3. The automatic robot wire-retrieving and fixing device according to claim 2, characterized in that: The second sealing cavity (434) is filled with hydraulic oil, and a connecting pipe (429) for transmitting hydraulic oil is connected between the second sealing cavity (434) and the first sealing cavity (425).

4. The automatic robot wire-retrieving and fixing device according to claim 3, characterized in that: Safety components (5) are provided on both sides of the fixed component (4). Each safety component (5) includes a safety housing (51). A first mating slider (52) is slidably installed inside the safety housing (51). An L-shaped baffle (53) is provided on the side of the safety housing (51) away from the fixed component (4). A safety stop bar (54) is rotatably installed on the side of the safety housing (51) close to the fixed component (4). A change slider (55) is slidably installed inside the safety housing (51). A shift stop bar (541) is fixedly installed at the lower end of the safety stop bar (54). A torsion spring is fixedly connected between the safety stop bar (54) and the safety housing (51). The change slider (55) has a helical inclined surface. A connecting slide bar (56) is fixedly connected between the change slider (55) and the first mating slider (52). A plurality of evenly distributed return springs (57) are fixedly installed between the first mating slider (52) and the safety housing (51).

5. The automatic robot wire-retrieving and fixing device according to claim 4, characterized in that: The transposition component (1) is provided with transport rails (3) on both sides for guiding the overhead wire car, and the L-shaped baffle (53) is fixedly installed on the transport rails (3).

6. The automatic robot wire-retrieving and fixing device according to claim 5, characterized in that: The upper surface of the shifting component (1) is fixedly mounted with a plurality of evenly distributed drive cylinders (13), and the telescopic ends of the drive cylinders (13) are fixedly connected to the fixed component (4).

7. The automatic robot wire-retrieving and fixing device according to claim 6, characterized in that: A transposition motor (14) is fixedly installed in the middle of the upper surface of the transposition component (1). The transposition motor (14) is fixedly installed on the ceiling of the external factory building by a bracket. A plurality of first connecting brackets (12) are fixedly installed on the upper surface of the transposition component (1). The first connecting brackets (12) are slidably connected to the ceiling of the external factory building.

8. The automatic robot wire-retrieving and fixing device according to claim 7, characterized in that: Below the shifting component (1) is a lifting component (2) for supporting the overhead wire car. The lifting component (2) includes a lifting cylinder (21). The telescopic end of the lifting cylinder (21) is rotatably mounted with a support platform (22). Multiple evenly distributed guide brackets (23) are fixedly mounted on the upper surface of the support platform (22).

Images