Pull rope type anti-overwinding switch

Abstract

The invention discloses a pull rope type anti-overwinding switch, and belongs to the technical field of cranes, the pull rope type anti-overwinding switch comprises a shell, a pull rod is arranged at the lower end in the shell, a spring seat is arranged on the outer side of the pull rod, a first spring is arranged in the spring seat on the surface of the pull rod, and a steel wire rope is arranged at the lower end of the pull rod. The cover plate rotates on the shell through a hinge, the cover plate rotates to drive an arc-shaped block to enter a folded plate through a connecting frame, when the arc-shaped block touches an arc-shaped clamping block, the arc-shaped block pushes a sliding rod at one end of the arc-shaped clamping block to slide in the folded plate, a second spring is compressed, and when a clamping groove in the arc-shaped block corresponds to the arc-shaped clamping block in position, the arc-shaped clamping block is pushed to slide in the folded plate. A second spring elastically stretches to push an arc-shaped clamping block at one end of a sliding rod to enter a clamping groove of the arc-shaped block, the effect of fixing the arc-shaped block and the cover plate is achieved, the cover plate can be conveniently and rapidly opened and closed and fixed through the arrangement of a connecting assembly, and a microswitch and the like in the shell can be conveniently overhauled or replaced.

Description

Technical Field

[0001] The invention belongs to the technical field of cranes, and particularly relates to a pull - rope type anti - over - winding switch. Background Art

[0002] A crane refers to a multi - action lifting machine that vertically lifts and horizontally transports heavy objects within a certain range. It is also called a overhead crane, bridge crane, or hoist.

[0003] Chinese Patent Application No. 2019204197801 discloses a pull - rope type anti - over - winding switch with variable pulling force direction, which includes a housing, a cover plate, a gasket, a fixed - pulley - like bell mouth, a rubber sleeve, a spring seat, a spring, a pull rod, a steel wire rope, a micro - switch, a function switching module, a cable locking head, and a signal output cable. The invention can be widely applied to various lifting equipment such as truck cranes, wheel cranes, crawler cranes, and port cranes. By using the invention, the limitations of the installation position and installation form of the existing pull - rod type anti - over - winding switch can be broken through, common faults such as damage to the anti - over - winding switch caused by external impact and damage to the cable caused by pulling can be effectively avoided, the reliability of the anti - over - winding switch can be effectively improved, and the maintenance rate of the lifting equipment can be reduced; at the same time, it has multiple output signal switching functions such as digital quantity, analog quantity, normally open, and normally closed.

[0004] The above - mentioned disclosed patent is not convenient for quickly opening and closing and fixing the cover plate, thus making it inconvenient to overhaul or replace the micro - switch in the housing. At the same time, the original device is not convenient for winding and collecting the too - long output cable, and the practicability of the device is poor. Summary of the Invention

[0005] To solve the problems raised in the above background art, the invention provides a pull - rope type anti - over - winding switch, which has the characteristic of being convenient for quickly opening and closing and fixing the cover plate.

[0006] It includes a housing. At the lower end inside the housing, there is a pull rod. Outside the pull rod, there is a spring seat. Inside the spring seat on the surface of the pull rod, there is a first spring. At the lower end of the pull rod, there is a steel wire rope. At the position corresponding to the steel wire rope at the lower end of the housing, there is a fixed - pulley - like bell mouth. At the position corresponding to the pull rod at the upper end inside the housing, there is a micro - switch. On one side of the upper end of the housing, there is an output cable. At the front end of the housing, there is a cover plate, and the cover plate and the housing are connected through a connection component.

[0007] Preferably, the connection component includes a folding plate, an arc-shaped block, a pulling plate, a sliding rod, an arc-shaped clamping block, a second spring, a connecting frame, a clamping groove and a hinge. Among them, the cover plate and the housing are connected by a hinge. An arc-shaped block is arranged on one side of the cover plate, and the arc-shaped block and the cover plate are connected by a connecting frame. A folding plate is arranged at a position corresponding to the arc-shaped block at one end of the housing. An arc-shaped clamping block is arranged in the folding plate. A plurality of sliding rods are arranged at one end of the arc-shaped clamping block, and a pulling plate is arranged at the other end of the sliding rod. A second spring is arranged on the surface of the sliding rod between the arc-shaped clamping block and the folding plate. A clamping groove corresponding to the arc-shaped clamping block is arranged in the arc-shaped block.

[0008] Preferably, one end of the arc-shaped clamping block and one end of the arc-shaped block are both arc-shaped structures, and a sliding hole corresponding to the sliding rod is arranged in the folding plate.

[0009] Preferably, after the arc-shaped clamping block enters the clamping groove, the side of the arc-shaped clamping block is in close contact with the inner wall of the clamping groove, and the arc-shaped clamping block and the sliding rod are of a welded integral structure.

[0010] Preferably, a bottom plate is arranged on the upper end of the housing near the output cable. A winding rod is arranged on the upper end of the bottom plate. A top plate is arranged on the upper end of the winding rod. A plurality of folding rods are arranged on the surface of the winding rod. The bottom plate and the housing are connected by fixing bolts, and fixing holes corresponding to the fixing bolts are arranged on the upper end of the housing.

[0011] Preferably, a plurality of triangular plates are arranged between the winding rod and the bottom plate, and a rubber pad is adhered to the surface of the winding rod by glue.

[0012] Preferably, the plurality of folding rods are spirally distributed on the winding rod, and the winding rod and the bottom plate and the winding rod and the top plate are both welded by spot welding.

[0013] Preferably, through holes corresponding to the fixing bolts are arranged in the bottom plate, and the plurality of triangular plates are staggered from the through holes.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. By setting the connection component, when the cover plate needs to be closed, push the cover plate. The cover plate rotates on the housing through the hinge. When the cover plate rotates, it drives the arc-shaped block to enter the folding plate through the connecting frame. When the arc-shaped block touches the arc-shaped clamping block, the arc-shaped block pushes the sliding rod at one end of the arc-shaped clamping block to slide in the folding plate, and the second spring is compressed. When the clamping groove in the arc-shaped block corresponds to the position of the arc-shaped clamping block, the second spring rebounds and pushes the arc-shaped clamping block at one end of the sliding rod into the clamping groove of the arc-shaped block, achieving the effect of fixing the arc-shaped block and the cover plate. When the cover plate needs to be opened, pull the arc-shaped clamping block at one end of the sliding rod out of the clamping groove of the arc-shaped block through the pulling plate, and the cover plate can be opened. By setting the connection component, it is convenient to quickly switch and fix the cover plate, and it is convenient to repair or replace the micro switch in the housing.

[0016] 2. The present invention fixes the base plate at the lower end of the winding rod on the upper end of the housing, and then screws the fixing bolts on the base plate into the fixing holes at the upper end of the housing, achieving the effect of fixing the base plate and the winding rod. When the output cable is too long, the output cable can be wound around the winding rod. At the same time, several folding rods on the winding rod can support and limit the output cable. By setting the winding rod, the too-long output cable can be wound and rolled up, improving the practicability of the device.

[0017] 3. The present invention makes the winding rod and the base plate more firm by arranging several triangular plates between the winding rod and the base plate, sets a rubber pad on the surface of the winding rod to play an anti-slip role, and at the same time avoids abrasion of the output cable by the winding rod. By setting the arc-shaped surfaces at one ends of the arc-shaped block and the arc-shaped clamping block, when the arc-shaped block contacts the arc-shaped clamping block, the arc-shaped block can push the arc-shaped clamping block to move automatically. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view of the present invention;

[0019] Figure 2 is a perspective view of the present invention when the base plate is installed;

[0020] Figure 3 is a perspective view of the folding plate of the present invention;

[0021] Figure 4 is a sectional perspective view of the arc-shaped block of the present invention;

[0022] Figure 5 is the present invention Figure 2 magnified view of part A;

[0023] In the figure: 1, housing; 2, connection assembly; 21, folding plate; 22, arc-shaped block; 23, pulling plate; 24, sliding rod; 25, arc-shaped clamping block; 26, second spring; 27, connecting frame; 28, clamping groove; 29, hinge; 3, spring seat; 4, pulling rod; 5, imitation fixed pulley bell mouth; 6, steel wire rope; 7, first spring; 8, top plate; 9, cover plate; 10, output cable; 11, winding rod; 12, micro switch; 13, base plate; 14, folding rod; 15, fixing bolt; 16, fixing hole; 17, triangular plate; 18, rubber pad. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Embodiment 1

[0026] Please refer to Figures 1-5 , the present invention provides the following technical solution: A rope-pulling type anti-overwinding switch, which includes a housing 1. At the lower end inside the housing 1, there is a pull rod 4. Outside the pull rod 4, there is a spring seat 3. Inside the spring seat 3 on the surface of the pull rod 4, there is a first spring 7. At the lower end of the pull rod 4, there is a steel wire rope 6. At the position corresponding to the steel wire rope 6 at the lower end of the housing 1, there is an imitation fixed pulley bell mouth 5. At the position corresponding to the pull rod 4 at the upper end inside the housing 1, there is a microswitch 12. On one side at the upper end of the housing 1, there is an output cable 10. At the front end of the housing 1, there is a cover plate 9, and the cover plate 9 and the housing 1 are connected through a connection assembly 2.

[0027] Specifically, the connection assembly 2 includes a folding plate 21, an arc-shaped block 22, a pull plate 23, a sliding rod 24, an arc-shaped clamping block 25, a second spring 26, a connecting frame 27, a clamping groove 28 and a hinge 29. Among them, the cover plate 9 and the housing 1 are connected through the hinge 29. On one side of the cover plate 9, there is an arc-shaped block 22, and the arc-shaped block 22 and the cover plate 9 are connected through the connecting frame 27. At the position corresponding to the arc-shaped block 22 at one end of the housing 1, there is a folding plate 21. In the folding plate 21, there is an arc-shaped clamping block 25. At one end of the arc-shaped clamping block 25, there are several sliding rods 24. At the other end of the sliding rod 24, there is a pull plate 23. On the surface of the sliding rod 24 between the arc-shaped clamping block 25 and the folding plate 21, there is a second spring 26. In the arc-shaped block 22, there is a clamping groove 28 corresponding to the arc-shaped clamping block 25.

[0028] By adopting the above technical solution, when the cover plate 9 needs to be closed, push the cover plate 9. The cover plate 9 rotates on the housing 1 through the hinge 29. The rotation of the cover plate 9 drives the arc-shaped block 22 to enter the folding plate 21 through the connecting frame 27. When the arc-shaped block 22 touches the arc-shaped clamping block 25, the arc-shaped block 22 pushes the sliding rod 24 at one end of the arc-shaped clamping block 25 to slide in the folding plate 21, and the second spring 26 is compressed. When the clamping groove 28 in the arc-shaped block 22 corresponds to the position of the arc-shaped clamping block 25, the second spring 26 rebounds and pushes the arc-shaped clamping block 25 at one end of the sliding rod 24 into the clamping groove 28 of the arc-shaped block 22, achieving the effect of fixing the arc-shaped block 22 and the cover plate 9. When the cover plate 9 needs to be opened, pull the arc-shaped clamping block 25 at one end of the sliding rod 24 out of the clamping groove 28 of the arc-shaped block 22 through the pull plate 23, and the cover plate 9 can be opened. By setting the connection assembly 2, it is convenient to quickly switch and fix the cover plate 9, and it is convenient to repair or replace the microswitch 12 and the like in the housing 1.

[0029] Specifically, one end of the arc-shaped clamping block 25 and one end of the arc-shaped block 22 are both set as arc-shaped structures, and in the folding plate 21, there are sliding holes corresponding to the sliding rods 24.

[0030] By adopting the above technical solution, one end of the arc-shaped block 22 and the arc-shaped clamping block 25 are both set as arc-shaped surfaces. When the arc-shaped block 22 contacts the arc-shaped clamping block 25, the arc-shaped block 22 can push the arc-shaped clamping block 25 to move automatically, and the sliding rod 24 can slide in the folding plate 21.

[0031] Specifically, after the arc-shaped clamping block 25 enters the card slot 28, the side of the arc-shaped clamping block 25 is closely attached to the inner wall of the card slot 28, and the arc-shaped clamping block 25 and the sliding rod 24 are of a welded integral structure.

[0032] By adopting the above technical solution, after the arc-shaped clamping block 25 enters the card slot 28, the limiting effect of the arc-shaped clamping block 25 on the arc-shaped block 22 is better, and the welded integral structure of the arc-shaped clamping block 25 and the sliding rod 24 is more durable.

[0033] When this embodiment is in use, when the rope-pulling anti-overwinding switch is in use, the device is installed in a suitable position. When the lifting device of the crane descends, the weight connected to the end of the steel wire rope 6 moves downward together under the action of gravity. The weight pulls the steel wire rope 6 and then pulls the pull rod 4. The micro switch 12 is in a free state, and the anti-overwinding switch outputs a set of signals. When the lifting device of the crane rises to the set limit height, the lifting device supports the weight, the steel wire rope 6 is no longer pulled by the weight, and the pull rod 4 is bounced back to the un-pulled state under the elastic force of the first spring 7. The micro switch 12 is pressed by the pull rod 4, and the anti-overwinding switch outputs a set of changing signals, and the lifting device stops rising, realizing the height limit function. By setting the connecting component 2, when the cover plate 9 needs to be closed, the cover plate 9 is pushed. The cover plate 9 rotates on the housing 1 through the hinge 29. The rotation of the cover plate 9 drives the arc-shaped block 22 to enter the folding plate 21 through the connecting frame 27. When the arc-shaped block 22 touches the arc-shaped clamping block 25, the arc-shaped block 22 pushes the sliding rod 24 at one end of the arc-shaped clamping block 25 to slide in the folding plate 21, and the second spring 26 is compressed. When the card slot 28 in the arc-shaped block 22 corresponds to the position of the arc-shaped clamping block 25, the second spring 26 rebounds and pushes the arc-shaped clamping block 25 at one end of the sliding rod 24 into the card slot 28 of the arc-shaped block 22, achieving the effect of fixing the arc-shaped block 22 and the cover plate 9. When the cover plate 9 needs to be opened, the arc-shaped clamping block 25 at one end of the sliding rod 24 is pulled out of the card slot 28 of the arc-shaped block 22 through the pull plate 23, and the cover plate 9 can be opened. By setting the connecting component 2, it is convenient to quickly switch and fix the cover plate 9, facilitating the maintenance or replacement of the micro switch 12 and the like in the housing 1.

[0034] Embodiment 2

[0035] The difference between this embodiment and Embodiment 1 is that: a bottom plate 13 is arranged on the upper end of the housing 1 near the output cable 10. A winding rod 11 is arranged on the upper end of the bottom plate 13. A top plate 8 is arranged on the upper end of the winding rod 11. A plurality of folding rods 14 are arranged on the surface of the winding rod 11. The bottom plate 13 and the housing 1 are connected by fixing bolts 15. Fixing holes 16 corresponding to the fixing bolts 15 are arranged on the upper end of the housing 1.

[0036] By adopting the above technical solution, by arranging the winding rod 11, placing the bottom plate 13 at the lower end of the winding rod 11 on the upper end of the housing 1, and then screwing the fixing bolt 15 on the bottom plate 13 into the fixing hole 16 at the upper end of the housing 1, the effect of fixing the bottom plate 13 and the winding rod 11 is achieved. When the output cable 10 is too long, the output cable 10 can be wound around the winding rod 11. At the same time, several folding rods 14 on the winding rod 11 can play a role in supporting and limiting the output cable 10. By arranging the winding rod 11, the too-long output cable 10 can be wound and wound up, improving the practicability of the device.

[0037] Specifically, several triangular plates 17 are arranged between the winding rod 11 and the bottom plate 13, and a rubber pad 18 is adhesively bonded to the surface of the winding rod 11 with glue.

[0038] By adopting the above technical solution, by arranging several triangular plates 17 between the winding rod 11 and the bottom plate 13, the winding rod 11 and the bottom plate 13 are made more firm. The rubber pad 18 arranged on the surface of the winding rod 11 plays an anti-slip role and at the same time avoids the winding rod 11 from wearing the output cable 10.

[0039] Specifically, several folding rods 14 are spirally distributed on the winding rod 11, and both between the winding rod 11 and the bottom plate 13 and between the winding rod 11 and the top plate 8 are welded by spot welding.

[0040] By adopting the above technical solution, several folding rods 14 are convenient for supporting and limiting the output cable 10 wound around the winding rod 11, and spot welding makes the connection between the winding rod 11 and the bottom plate 13 and between the winding rod 11 and the top plate 8 more firm.

[0041] Specifically, through holes corresponding to the fixing bolts 15 are arranged in the bottom plate 13, and several triangular plates 17 are staggered from the through holes.

[0042] By adopting the above technical solution, it is convenient to pass the fixing bolt 15 through the bottom plate 13 for fixing, and the staggering of several triangular plates 17 from the through holes avoids the triangular plates 17 from affecting the installation of the fixing bolt 15.

[0043] In use of this embodiment, by arranging the winding rod 11, the bottom plate 13 at the lower end of the winding rod 11 is placed on the upper end of the housing 1, and then the fixing bolts 15 on the bottom plate 13 are screwed into the fixing holes 16 at the upper end of the housing 1, achieving the effect of fixing the bottom plate 13 and the winding rod 11. When the output cable 10 is too long, the output cable 10 can be wound around the winding rod 11. At the same time, several folding rods 14 on the winding rod 11 can support and limit the output cable 10. By arranging the winding rod 11, the too-long output cable 10 can be wound and wound up, improving the practicability of the device. By arranging several triangular plates 17 between the winding rod 11 and the bottom plate 13, the winding rod 11 and the bottom plate 13 are made more firm. A rubber pad 18 is arranged on the surface of the winding rod 11 to play an anti-slip role and at the same time prevent the winding rod 11 from wearing the output cable 10.

[0044] In the present invention, the structures and working principles of the housing 1, the spring seat 3, the pull rod 4, the imitation fixed pulley bell mouth 5, the steel wire rope 6, the first spring 7, the cover plate 9, the output cable 10 and the micro switch 12 have been disclosed in a pull-force variable-direction type cable-pulling anti-overwinding switch with the Chinese patent application number 2019204197801. Its working principle is that when the hoisting device of the crane descends, the weight connected to the end of the steel wire rope 6 moves downward together under the action of gravity. The weight pulls the steel wire rope 6 and then pulls the pull rod 4. The micro switch 12 is in a free state, and the anti-overwinding switch outputs a set of signals. When the hoisting device of the crane rises to the set limit height, the hoisting device supports the weight, the steel wire rope 6 is no longer pulled by the weight, the pull rod 4 is bounced back to the non-pulled state under the elastic force of the first spring 7, the micro switch 12 is pressed by the pull rod 4, the anti-overwinding switch outputs a set of changing signals, and the hoisting device stops rising, realizing the height limit function.

[0045] Working principle and usage process of the present invention: When the rope-pulling type over-winding prevention switch is in use, the device is installed at a suitable position. When the hoisting device of the crane descends, the weight connected to the end of the steel wire rope 6 moves downward under the action of gravity. The weight pulls the steel wire rope 6, which in turn pulls the pull rod 4. The micro switch 12 is in a free state, and the over-winding prevention switch outputs a set of signals. When the hoisting device of the crane rises to the set limit height, the hoisting device supports the weight, and the steel wire rope 6 is no longer pulled by the weight. The pull rod 4 is bounced back to the un-pulled state under the elastic force of the first spring 7, and the micro switch 12 is pressed by the pull rod 4. The over-winding prevention switch outputs a set of changing signals, and the hoisting device stops rising, realizing the height limit function. By setting the connecting component 2, when the cover plate 9 needs to be closed, the cover plate 9 is pushed. The cover plate 9 rotates on the housing 1 through the hinge 29. The rotation of the cover plate 9 drives the arc-shaped block 22 into the folding plate 21 through the connecting frame 27. When the arc-shaped block 22 touches the arc-shaped clamping block 25, the arc-shaped block 22 pushes the sliding rod 24 at one end of the arc-shaped clamping block 25 to slide in the folding plate 21, and the second spring 26 is compressed. When the card slot 28 in the arc-shaped block 22 corresponds to the position of the arc-shaped clamping block 25, the second spring 26 rebounds and pushes the arc-shaped clamping block 25 at one end of the sliding rod 24 into the card slot 28 of the arc-shaped block 22, achieving the effect of fixing the arc-shaped block 22 and the cover plate 9. When the cover plate 9 needs to be opened, the arc-shaped clamping block 25 at one end of the sliding rod 24 is pulled out of the card slot 28 of the arc-shaped block 22 through the pull plate 23, and the cover plate 9 can be opened. By setting the connecting component 2, it is convenient to quickly switch and fix the cover plate 9, facilitating the maintenance or replacement of the micro switch 12 and the like in the housing 1. By setting the winding rod 11, the bottom plate 13 at the lower end of the winding rod 11 is placed on the upper end of the housing 1, and then the fixing bolt 15 on the bottom plate 13 is screwed into the fixing hole 16 at the upper end of the housing 1, achieving the effect of fixing the bottom plate 13 and the winding rod 11. When the output cable 10 is too long, the output cable 10 can be wound around the winding rod 11. At the same time, several folding rods 14 on the winding rod 11 can play a role in supporting and limiting the output cable 10. By setting the winding rod 11, the too-long output cable 10 can be wound and wound up, improving the practicability of the device. By setting several triangular plates 17 between the winding rod 11 and the bottom plate 13, the winding rod 11 and the bottom plate 13 are made more firm. A rubber pad 18 is arranged on the surface of the winding rod 11 to play an anti-slip role and at the same time avoid the winding rod 11 from wearing the output cable 10.

[0046] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rope-pulling type overwind prevention switch, comprising a housing, characterized in that: A pull rod is arranged at the lower end inside the housing. A spring seat is arranged outside the pull rod. A first spring is arranged inside the spring seat on the surface of the pull rod. A steel wire rope is arranged at the lower end of the pull rod. A bell mouth of a pseudo-fixed pulley corresponding to the steel wire rope is arranged at the lower end of the housing. A microswitch is arranged at the position corresponding to the pull rod at the upper end inside the housing. An output cable is arranged at one side of the upper end of the housing. A cover plate is arranged at the front end of the housing. The cover plate and the housing are connected through a connecting component.

2. The rope-pulling type overwind prevention switch according to claim 1, characterized in that: The connecting component includes a folding plate, an arc-shaped block, a pulling plate, a sliding rod, an arc-shaped clamping block, a second spring, a connecting frame, a clamping groove and a hinge. Among them, the cover plate and the housing are connected through the hinge. An arc-shaped block is arranged at one side of the cover plate. The arc-shaped block and the cover plate are connected through the connecting frame. A folding plate is arranged at the position corresponding to the arc-shaped block at one end of the housing. An arc-shaped clamping block is arranged in the folding plate. A plurality of sliding rods are arranged at one end of the arc-shaped clamping block. A pulling plate is arranged at the other end of the sliding rod. A second spring is arranged on the surface of the sliding rod between the arc-shaped clamping block and the folding plate. A clamping groove corresponding to the arc-shaped clamping block is arranged in the arc-shaped block.

3. The pull rope type overwind switch according to claim 2, characterized in that: One end of the arc-shaped clamping block and one end of the arc-shaped block are both arranged as arc-shaped structures. A sliding hole corresponding to the sliding rod is arranged in the folding plate.

4. A pull - rope type over - winding prevention switch according to claim 2, characterized in that: After the arc-shaped clamping block enters the clamping groove, the side of the arc-shaped clamping block is closely attached to the inner wall of the clamping groove. The arc-shaped clamping block and the sliding rod are of a welded integral structure.

5. The rope-pulling type overwind prevention switch according to claim 1, characterized in that: A bottom plate is arranged at one side close to the output cable at the upper end of the housing. A winding rod is arranged at the upper end of the bottom plate. A top plate is arranged at the upper end of the winding rod. A plurality of folding rods are arranged on the surface of the winding rod. The bottom plate and the housing are connected through fixing bolts. Fixing holes corresponding to the fixing bolts are arranged at the upper end of the housing.

6. The rope-pulling type overwind prevention switch according to claim 5, wherein: A plurality of triangular plates are arranged between the winding rod and the bottom plate. A rubber pad is adhesively bonded to the surface of the winding rod through glue.

7. A pull - rope type over - winding prevention switch according to claim 5, characterized in that: The plurality of folding rods are spirally distributed on the winding rod. The winding rod and the bottom plate and the winding rod and the top plate are both welded by spot welding.

8. A pull - rope type over - winding prevention switch according to claim 6, characterized in that: Through holes corresponding to the fixing bolts are arranged in the bottom plate. The plurality of triangular plates and the through holes are staggered from each other.

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