Aerial maintenance work anti-falling device

Abstract

The application relates to the technical field of high-altitude construction, in particular to a falling-prevention device for high-altitude maintenance work, which comprises a base plate, a collecting groove, a surrounding part, a control box, two hoists and two safety devices, the collecting groove is fixedly connected to the lower surface of the base plate, universal wheels are arranged at the four corners of the lower surface of the collecting groove, the surrounding part is fixedly connected to the top end of the base plate, the control box is fixedly connected to the front middle part of the surrounding part, an alarm is arranged on the outer wall of the control box, the two hoists are fixedly connected to the left and right inner walls of the surrounding part, the hoists are electrically connected with the control box, and the two safety devices are fixedly connected to the top ends of the left and right sides of the surrounding part. The application has the safety warning function, can ensure that the staff can deal with the emergent safety situation in the first time, has the high safety coefficient, improves the stability of the base plate and the surrounding part, has the function of preventing the building materials from falling, avoids the high-altitude falling objects, and saves the building material use cost.

Description

Technical Field

[0001] This invention relates to the field of high-altitude operations in building construction, and in particular to a fall protection device for high-altitude maintenance operations. Background Technology

[0002] A suspended platform is a construction tool used for high-altitude operations in building construction, specifically for curtain wall installation and exterior wall cleaning. It is a cantilevered structure erected on a building or structure, using a lifting mechanism to drive a suspended platform that moves up and down along the building or structure's facade via steel wire ropes. It also serves as a work platform for operators and is one of the main pieces of equipment for high-altitude operations.

[0003] The suspended platform mainly consists of a suspended platform, a hoist, a safety lock, a suspension mechanism, and an electrical control box. With the hoist controlled by the electrical control box, the hoist moves up and down along the wire rope, causing the suspended platform to rise or fall. The purpose of the safety lock is to automatically and quickly lock the wire rope when the suspended platform tilts, ensuring that the suspended platform does not fall or continue to tilt.

[0004] The lifting and lowering of the suspended platform must maintain a certain distance from the wall. The suspended platform is simply suspended by steel wire ropes with few support pads, which makes it prone to swaying during lifting and lowering. During wall painting, curtain wall installation and exterior wall design, building materials inevitably fall. Falling objects from heights pose safety hazards and waste building materials.

[0005] Although safety locks are responsible for preventing falls from suspended platforms, these platforms are often quite long. If there are even slight signs of a platform slipping, workers will not be able to detect it and will not be able to provide early warning of platform displacement, resulting in a low safety factor. Summary of the Invention

[0006] In order to overcome the shortcomings of existing technologies, such as the inability to add lifting support points to the suspended platform, the inability to prevent falling objects, and the lack of early warning for falling objects from the suspended platform, the present invention aims to solve the technical problem of a suspended platform for construction.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a fall protection device for high-altitude maintenance operations, comprising a base plate, a collection trough, a guardrail, a control box, two hoists, and two safety devices. The collection trough is fixedly connected to the lower surface of the base plate, and casters are provided at the four corners of the lower surface of the collection trough. The guardrail is fixedly connected to the top of the base plate. The control box is fixedly connected to the middle of the front side of the guardrail, and an alarm is provided on the outer wall of the control box. The two hoists are respectively fixedly connected to the left and right inner walls of the guardrail, and the hoists are electrically connected to the control box. The two safety devices are respectively fixedly connected to the top of the left and right sides of the guardrail. The device also includes: two anti-detachment warning mechanisms, respectively fixedly connected to the top of the left and right sides of the guardrail, with the anti-detachment warning mechanisms located at the center of the safety devices; and a falling object prevention mechanism, located at the top of the rear side of the guardrail, with the bottom end of the falling object prevention mechanism connected to the rear side of the inner cavity of the collection trough via a pin.

[0008] The purpose is to drive the rotating assembly to move back and forth. The anti-detachment warning mechanism includes: a mounting plate, fixedly connected to the top of the enclosure; a limiting cylinder, fixedly connected to the right side of the mounting plate, and the inner cavity of the limiting cylinder is rectangular; an electric telescopic rod, installed at the center of the front side of the limiting cylinder and electrically connected to the control box; and a rotating assembly, which can slide back and forth and is inserted into the inner cavity of the limiting cylinder, and the front side of the rotating assembly is connected to the output end of the electric telescopic rod.

[0009] Preferably, the purpose is to detect whether the enclosure rises or falls during operation. The rotating assembly includes: a U-shaped frame that can slide back and forth and is inserted into the inner cavity of the limiting cylinder; a second rotating shaft that is rotatably mounted at the center of the inner cavity of the U-shaped frame via a bearing, and the right end of the second rotating shaft extends out of the right side wall of the U-shaped frame; a guide wheel that is mounted on the outer wall of the second rotating shaft; a turntable that is mounted on the right end of the outer wall of the second rotating shaft, and the outer wall of the turntable has a notch; a dust cover that is mounted on the rear end of the right side wall of the U-shaped frame and covers the outside of the turntable; and a limit switch that is electrically connected to the control box and mounted on the outer wall of the dust cover, and the top of the limit switch is inserted into the notch.

[0010] Preferably, the outer wall of the guide wheel is uniformly provided with raised ridges along the circumference.

[0011] Preferably, both sides of the notch are symmetrical slopes.

[0012] Preferably, with the aim of increasing the support points of the enclosure and receiving falling building materials from the exterior wall, the falling object prevention mechanism includes: a housing, fixedly connected to the center of the rear top of the enclosure; a motor, installed on the front end of the right side wall of the housing, and electrically connected to a control box; a worm gear, one end of which is installed at the output end of the motor, and the other end of the worm gear is connected to the left inner wall of the housing via a bearing; two first rotating shafts, each rotatable via bearings, are installed at the left and right ends of the rear cavity of the housing, and the first rotating shafts are arranged in a vertical direction; a worm wheel, locked to the bottom end of the outer wall of the first rotating shaft by a set screw, and the worm wheel meshes with the worm gear; a first connecting rod, one end of which is fixedly connected to the top of the outer wall of the first rotating shaft; a support rod, fixedly connected to the bottom rear end of the housing in a horizontal direction; and two second connecting rods, one end of which... The second link is rotatably mounted on the left and right ends of the support rod via pins; the third link is rotatably mounted on the other end of the second link via a pin; the support frame is mounted on the other end of the third link via a pin, and the front side of the support frame has a slide rail in the left and right direction, with both ends of the slide rail closed, and the inner cavity of the slide rail is dovetail-shaped; two sliders are slidably inserted into the left and right ends of the inner cavity of the slide rail, and the front side of the slider is connected to the other end of the third link via a pin; two rollers are rotatably mounted on the left and right ends of the rear side of the support frame; the first guide plate is rotatably mounted in the inner cavity of the support frame via a pin, and the first guide plate is hollow; the second guide plate is inserted into the inner cavity of the first guide plate, and the bottom end of the second guide plate is connected to the inner cavity of the collection trough via a pin;

[0013] When the motor drives the worm to rotate clockwise or counterclockwise, the worm can drive the two worm wheels to rotate in opposite directions at the same time, so that the two first connecting rods can swing inward or outward at the same time.

[0014] Preferably, the threads on the left and right sides of the outer wall of the worm are positive and negative threads.

[0015] Preferably, the upper surface of the first guide plate is uniformly provided with anti-slip ridges, and the anti-slip ridges are triangular.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. This invention uses an electric telescopic rod to drive the U-shaped frame to move back and forth, thereby moving the guide wheel away from or into contact with the wire rope. When the enclosure moves up and down, the guide wheel moves with the enclosure and rotates, thereby causing the second rotating shaft to drive the turntable to rotate. The notch presses the limit switch, triggering the limit switch and causing the alarm on the control box to sound. It has a safety warning function, ensuring that staff can deal with sudden safety situations in a timely manner, with a high safety factor.

[0018] 2. This invention uses a motor to drive a worm gear to rotate clockwise. With the cooperation of the worm gear and worm wheel, the first rotating shaft drives the first connecting rod to swing inward. The slider slides inward along the slide rail. Under the limiting action of the second and third connecting rods on the support frame, the first connecting rod pushes the support frame backward, allowing the roller to contact the outer wall, increasing the support points for the vertical movement of the enclosure. The first and second guide plates conduct falling building materials, causing them to fall into the collection trough. Therefore, the stability of the base plate and enclosure is improved, and the function of preventing building materials from falling is provided, which not only avoids falling objects from heights but also saves on the cost of building materials. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention;

[0020] Figure 2 This is an enlarged view of point A in the present invention;

[0021] Figure 3 This is a schematic diagram of the anti-hair loss early warning mechanism of the present invention;

[0022] Figure 4 This is a top cross-sectional view of the anti-hair loss early warning mechanism of the present invention;

[0023] Figure 5 This is a right-side cross-sectional view of the anti-hair loss early warning mechanism of the present invention;

[0024] Figure 6 This is a schematic diagram of the anti-falling object mechanism of the present invention;

[0025] Figure 7 This is a top cross-sectional view of the anti-falling object mechanism of the present invention.

[0026] In the diagram: 1-Baseboard, 2-Collection trough, 3-Enclosure, 4-Control box, 5-Helper, 6-Safety device, 7-Anti-detachment warning mechanism, 8-Anti-falling object mechanism, 71-Mounting plate, 72-Limit cylinder, 73-Electric telescopic rod, 74-Rotating assembly, 81-Outer shell, 82-Motor, 83-Worm gear, 84-First rotating shaft, 85-Worm wheel, 86-First connecting rod, 87-Support rod, 88-Second connecting rod, 89-Third connecting rod, 810-Support frame, 811-Slide rail, 812-Slider, 813-Roller, 814-First guide plate, 815-Second guide plate, 741-U-shaped frame, 742-Second rotating shaft, 743-Guide wheel, 744-Turntable, 745-Notch, 746-Dust cover, 747-Limit switch. Detailed Implementation

[0027] 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.

[0028] This invention provides a technical solution: a fall protection device for high-altitude maintenance operations, such as... Figure 1-2 As shown, the system includes a base plate 1, a collection tank 2, a protective enclosure 3, a control box 4, two hoists 5, and two safety devices 6. The collection tank 2 is fixedly connected to the lower surface of the base plate 1 and is used to store fallen building materials. The four corners of the lower surface of the collection tank 2 are equipped with casters for easy movement on the ground. The protective enclosure 3 is fixedly connected to the top of the base plate 1 and provides protection for workers operating at heights. The control box 4 is fixedly connected to the front center of the protective enclosure 3, and an alarm is installed on the outer wall of the control box 4. The alarm is designed to detect the base plate 1 and the protective enclosure. The fall protection system 3 includes two hoists 5 fixedly connected to the left and right inner walls of the enclosure 3, and the hoists 5 are electrically connected to the control box 4. Two safety devices 6 are fixedly connected to the top of the left and right sides of the enclosure 3. It also includes an anti-detachment warning mechanism 7 and an anti-falling object mechanism 8. There are two anti-detachment warning mechanisms 7, which are fixedly connected to the top of the left and right sides of the enclosure 3, and the anti-detachment warning mechanism 7 is located at the center of the safety device 6. The anti-falling object mechanism 8 is located at the top of the rear side of the enclosure 3, and the bottom end of the anti-falling object mechanism 8 is connected to the rear side of the inner cavity of the collection tank 2 by a pin.

[0029] The hanger is installed on the top of the building and a steel wire rope is lowered down. The steel wire rope passes through the hoist 5 and the safety device 6. The hoist 5 is controlled by the control box 4 to make the enclosure 3 move up and down, realizing the overall movement of the device. The safety device 6 is responsible for locking the enclosure 3 and the base plate 1.

[0030] like Figure 3-4 As shown, the anti-detachment warning mechanism 7 includes a mounting plate 71, a limiting cylinder 72, an electric telescopic rod 73, and a rotating assembly 74. The mounting plate 71 is fixedly connected to the top of the enclosure 3; the limiting cylinder 72 is fixedly connected to the right side of the mounting plate 71, and the inner cavity of the limiting cylinder 72 is rectangular, used to limit the U-shaped frame 741 and ensure the stability of the U-shaped frame 741; the electric telescopic rod 73 is installed at the center of the front side of the limiting cylinder 72 and is electrically connected to the control box 4, used to drive the U-shaped frame 741 to move back and forth; the rotating assembly 74 can slide back and forth and is inserted into the inner cavity of the limiting cylinder 72, and the front side of the rotating assembly 74 is connected to the output end of the electric telescopic rod 73.

[0031] As a preferred option, further, such as Figure 4-5As shown, the rotating assembly 74 includes a U-shaped frame 741, a second rotating shaft 742, a guide wheel 743, a turntable 744, a notch 745, a dust cover 746, and a limit switch 747. The U-shaped frame 741 is slidably inserted into the inner cavity of the limiting cylinder 72. The second rotating shaft 742 is rotatably mounted at the center of the inner cavity of the U-shaped frame 741 via bearings, and the right end of the second rotating shaft 742 extends out of the right side wall of the U-shaped frame 741. Under the connecting action of the second rotating shaft 742, the guide wheel 743 and the turntable 744 can rotate synchronously. The guide wheel 743 is mounted on the outer wall of the second rotating shaft 742, and the outer wall surface of the guide wheel 743 is arc-shaped, which is consistent with the steel... The shape of the wire rope matches, increasing the contact area between the two; the turntable 744 is installed on the right end of the outer wall of the second rotating shaft 742, and the outer wall of the turntable 744 has a notch 745. Both sides of the notch 745 are symmetrical slopes. When the turntable 744 drives the notch 745 to rotate, the slope of the notch 745 can press the limit switch 747, thereby triggering the limit switch 747; the dust cover 746 is installed on the rear end of the right side wall of the U-shaped frame 741, and the dust cover 746 is fitted on the outside of the turntable 744; the limit switch 747 is electrically connected to the control box 4 and is installed on the outer wall of the dust cover 746, and the top of the limit switch 747 is inserted into the notch 745;

[0032] When the hoist 5 drives the enclosure 1 to rise or fall, the control box 4 controls the electric telescopic rod 73 to drive the U-shaped frame 741 to move forward along the inner wall of the limiting cylinder 72, so that the guide wheel 743 moves away from the wire rope until the enclosure 1 stops at the current height. The electric telescopic rod 73 pushes the U-shaped frame 741 to move backward, so that the guide wheel 743 contacts the wire rope. When the enclosure 3 moves upward or downward, the guide wheel 743 moves relative to the wire rope, and the guide wheel 743 rotates, which in turn causes the second rotating shaft 742 to drive the turntable 744 to rotate. The notch 745 slopes and presses the limit switch 747, which is triggered and sends an electrical signal back to the control box 4. The controller 4 starts to alarm, indicating that the base plate 1 is in an unstable state.

[0033] As a preferred option, the outer wall of the guide wheel 743 is evenly provided with protruding ridges along the circumference. The purpose is to increase the friction between the guide wheel 743 and the wire rope, so that the guide wheel 743 can rotate along the wire rope once the enclosure 3 moves upward or downward.

[0034] As a preferred option, further, such as Figure 6-7As shown, the anti-falling object mechanism 8 includes a housing 81, a motor 82, a worm gear 83, a first rotating shaft 84, a worm wheel 85, a first connecting rod 86, a support rod 87, a second connecting rod 88, a third connecting rod 89, a support frame 810, a slide rail 811, a slider 812, a roller 813, a first guide plate 814, and a second guide plate 815. The housing 81 is fixedly connected to the center of the rear top of the enclosure 3. The motor 82 is installed on the front end of the right side wall of the housing 81 and is electrically connected to the control box 4. The motor 82 is a forward and reverse reversible motor and has a brake. One end of the worm gear 83 is installed at the output end of the motor 82, and the other end of the worm gear 83 is connected to the left inner wall of the housing 81 through a bearing. When the worm 83 rotates clockwise or counterclockwise, the worm wheel 85 can rotate counterclockwise or clockwise. There are two first rotating shafts 84, which are rotatably mounted on the left and right ends of the rear side of the inner cavity of the housing 81 via bearings, and the first rotating shafts 84 are arranged vertically. The worm wheel 85 is locked to the bottom end of the outer wall of the first rotating shaft 84 by a set screw, and the worm wheel 85 is meshed with the worm 83. One end of the first connecting rod 86 is fixedly connected to the top end of the outer wall of the first rotating shaft 84. When the first connecting rod 86 swings inward or outward, it can pull the support frame 810 to move backward or forward. The support rod 87 is fixedly connected to the bottom end of the rear side of the housing 81 in the left-right direction. The second connecting rod... There are two second connecting rods 88, one end of which is rotatably mounted on the left and right ends of the support rod 87 via pins. One end of the third connecting rod 89 is rotatably mounted on the other end of the second connecting rod 88 via a pin. The second and third connecting rods 88 are of the same length. The cooperation of the second and third connecting rods 88 and 89 limits the support frame 810, enabling it to move linearly forward and backward. The support frame 810 is mounted on the other end of the third connecting rod 89 via a pin. A slide rail 811 is provided on the front side of the support frame 810 along the left and right directions, with both ends of the slide rail 811 closed. The inner cavity of the slide rail 811 is dovetail-shaped. There are two sliders 812, which can slide left and right. The slider 812 is inserted into the left and right ends of the inner cavity of the slide rail 811. The front side of the slider 812 is connected to the other end of the third connecting rod 89 by a pin. There are two rollers 813, which are rotatable and are respectively installed on the left and right ends of the rear side of the support frame 810. The first guide plate 814 is rotatably installed in the inner cavity of the support frame 810 by a pin, and the first guide plate 814 is hollow. The second guide plate 815 is inserted into the inner cavity of the first guide plate 814, and the bottom end of the second guide plate 815 is connected to the inner cavity of the collection groove 3 by a pin. The first guide plate 814 and the second guide plate 815 have telescopic capacity. Therefore, the first guide plate 814 can move with the support frame 810.

[0035] The control box 4 drives the motor 82 to rotate clockwise, causing the worm gear 83 to rotate clockwise. Since the threads on both sides of the worm gear 83 are in opposite directions, the first rotating shaft 84 drives the first connecting rod 86 to rotate inward. The slider 812 slides inward along the slide rail 811. The angle between the second connecting rod 88 and the third connecting rod 89 gradually increases, and the support frame 810 gradually moves backward. The first guide plate 814 and the second guide plate 815, which are linked to it, extend until the roller 813 contacts the outer wall. The top of the first guide plate 814 is close to the outer wall. The roller 813 provides support when the enclosure 3 rises or falls, preventing the base plate 1 from shaking. When workers are renovating the outer wall, the falling building materials will be caught by the first guide plate 814. The anti-slip ribs slow down the rolling speed of the building materials, allowing the building materials to enter the collection tank 2 through the first guide plate 814 and the second guide plate 815.

[0036] As a preferred option, the threads on the left and right sides of the outer wall of the worm 83 are reverse threads, so that the two worm wheels 85 rotate in opposite directions, thereby enabling the two first connecting rods 86 to swing outward or inward simultaneously.

[0037] As a preferred option, the upper surface of the first guide plate 814 is evenly provided with anti-slip ridges, and the anti-slip ridges are triangular, which can slow down the downward movement of building materials falling on the first guide plate 814 and prevent building materials from splashing.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An aerial maintenance work anti-falling device, comprising a base plate (1), a collection groove (2), a enclosure (3), a control box (4), two hoists (5) and two safety devices (6), the collection groove (2) is fixedly connected to the lower surface of the base plate (1), and the lower surface of the collection groove (2) is provided with universal wheels at the four corners, the enclosure (3) is fixedly connected to the top end of the base plate (1), the control box (4) is fixedly connected to the front middle part of the enclosure (3), and the outer wall of the control box (4) is provided with an alarm, the two hoists (5) are respectively fixedly connected to the left and right inner walls of the enclosure (3), and the hoist (5) is electrically connected with the control box (4), and the two safety devices (6) are respectively fixedly connected to the top ends of the left and right sides of the enclosure (3), characterized in that, Also includes: There are two anti-detachment warning mechanisms (7), which are fixedly connected to the top of the left and right sides of the enclosure (3) respectively, and the anti-detachment warning mechanism (7) is located at the center of the safety device (6); The falling object prevention mechanism (8) is located at the rear top of the enclosure (3), and the bottom end of the falling object prevention mechanism (8) is connected to the rear side of the inner cavity of the collection groove (2) by a pin. The anti-hair loss early warning mechanism (7) includes: Mounting plate (71) is fixedly connected to the top of the enclosure (3); The limiting cylinder (72) is fixedly connected to the right side of the mounting plate (71), and the inner cavity of the limiting cylinder (72) is rectangular; An electric telescopic rod (73) is installed at the center of the front side of the limiting cylinder (72) and is electrically connected to the control box (4); The rotating assembly (74) is slidably inserted into the inner cavity of the limiting cylinder (72), and the front side of the rotating assembly (74) is connected to the output end of the electric telescopic rod (73). The rotating assembly (74) includes: The U-shaped frame (741) can slide back and forth and be inserted into the inner cavity of the limiting cylinder (72); The second rotating shaft (742) is rotatably mounted at the center of the inner cavity of the U-shaped frame (741) via a bearing, and the right end of the second rotating shaft (742) extends out of the right side wall of the U-shaped frame (741); The guide wheel (743) is installed on the outer wall of the second rotating shaft (742); A turntable (744) is installed on the right end of the outer wall of the second rotating shaft (742), and a notch (745) is provided on the outer wall of the turntable (744). A dust cover (746) is installed on the rear end of the right side wall of the U-shaped frame (741), and the dust cover (746) is fitted over the outside of the turntable (744); Limit switch (747), which is electrically connected to control box (4), is installed on the outer wall of dust cover (746), and the top of limit switch (747) is inserted into notch (745); The falling object protection mechanism (8) includes: The outer shell (81) is fixedly connected to the center of the rear top of the enclosure (3); The motor (82) is installed on the front end of the right side wall of the housing (81), and the motor (82) is electrically connected to the control box (4); The worm (83) is installed at one end of the output end of the motor (82), and the other end of the worm (83) is connected to the left inner wall of the housing (81) by a bearing; There are two first rotating shafts (84), which are installed on the left and right ends of the rear cavity of the outer shell (81) respectively through bearings and can rotate on their own. The first rotating shafts (84) are arranged in the vertical direction. The worm gear (85) is locked to the bottom of the outer wall of the first rotating shaft (84) by a set screw, and the worm gear (85) is meshed with the worm (83); The first connecting rod (86) is fixedly connected at one end to the top of the outer wall of the first rotating shaft (84); The support rod (87) is fixedly connected to the rear bottom end of the outer casing (81) in the left-right direction; There are two second connecting rods (88), and one end of each second connecting rod (88) is rotatably mounted on the left and right ends of the support rod (87) via a pin. The third link (89) is rotatably mounted at the other end of the second link (88) via a pin. The support frame (810) is installed at the other end of the third link (89) by a pin. The front side of the support frame (810) is provided with a slide (811) in the left and right direction, and the two ends of the slide (811) are closed. The inner cavity of the slide (811) is dovetail shaped. Two sliders (812) are inserted into the left and right ends of the inner cavity of the slide rail (811) and can slide left and right. The front side of the slider (812) is connected to the other end of the third connecting rod (89) by a pin. Two rollers (813) are rotatable and are respectively installed on the left and right ends of the rear side of the support frame (810); The first guide plate (814) is rotatably mounted in the inner cavity of the support frame (810) via a pin, and the first guide plate (814) is hollow. The second guide plate (815) is inserted into the inner cavity of the first guide plate (814), and the bottom end of the second guide plate (815) is connected to the inner cavity of the collection groove (2) by a pin.

2. The fall protection device for high-altitude maintenance operations according to claim 1, characterized in that: The outer wall of the guide wheel (743) is uniformly provided with protruding ridges along the circumference.

3. The fall protection device for high-altitude maintenance operations according to claim 1, characterized in that: The notch (745) has symmetrical slopes on both sides.

4. A fall protection device for high-altitude maintenance operations according to claim 1, characterized in that: The threads on the left and right sides of the outer wall of the worm (83) are positive and negative threads.

5. A fall protection device for high-altitude maintenance operations according to claim 1, characterized in that: The upper surface of the first guide plate (814) is uniformly provided with anti-slip ridges, and the anti-slip ridges are triangular.

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