A crane winch protection device

Abstract

The present invention relates to the technical field of crane winches, and specifically to a crane winch protection device, which solves the problem that the existing device is not flexible enough to use; the present invention includes an anti-overwinding mechanism, which includes a fixed frame, a circular ring body is fixedly provided on the fixed frame, the circular ring body is parallel to the axial direction of the winch wheel, a connecting plate is slidably provided on the circular ring body, the connecting plate is connected to a fixed plate, a top plate is elastically connected to the side of the fixed plate away from the connecting plate, a top rod is provided on the side of the top plate close to the fixed plate, the top rod passes through the fixed plate, and a first conductive layer and a first insulating layer are sequentially provided near the end, a rotating rod perpendicular to the top rod is slidably provided outside the top rod near the end, the rotating rod is coaxial with the circular ring body, two first conductive sheets adapted to the first conductive layer are provided at the connection between the rotating rod and the top rod, the first conductive sheets are electrically connected to the motor, and rope holes are provided on the fixed plate and the top plate; the present invention can fix the fixed base to the machine at a certain angle according to the specific matching machine, and is flexible to use.

Description

Technical Field

[0001] The invention relates to the technical field of crane hoisting technology, and in particular to a crane hoisting protection device. Background Art

[0002] A winch is a small and light lifting device that uses a drum to wind a wire rope or chain to lift or pull heavy objects. It is also called a winch. A winch can lift vertically, pull heavy objects horizontally or tilted, and is mainly an electric winch. It can be used alone or as a component of machinery such as lifting, road construction, and mine hoisting. It is widely used because of its simple operation, large rope winding capacity, and convenient relocation. When electric winding control is used, overwinding may cause other accidents such as device damage.

[0003] After searching, the announcement number CN114148935B discloses a crane winch protection device, which relates to the technical field of winch cranes; in order to achieve the purpose of over-winding protection; it specifically includes a mounting frame, a motor is fixed to the outer wall of one side of the mounting frame through a motor seat, and the output end of the motor is rotatably connected to the winch wheel, and an adjusting sleeve is fixed to the outer walls on both sides of the mounting frame, and a fixed bracket is installed in the adjusting sleeve, and a guide rod is fixed to the top of the two fixed brackets, and a support plate is slidably connected to the outer wall of the guide rod, and a limit head is fixed to the outer wall of the top of the guide rod, and a spring is fixed between the limit head and the support plate, and a conductive ring is embedded in the outer wall of the bottom of the support plate; by setting a spherical protection block, a spherical sliding seat and a protective cover, the wire rope can be pre-passed through the rope hole of the spherical protection block, the spherical protection block and the protective cover can protect the wire rope to a certain extent, and the spherical protection block can be flexibly rotated in the spherical sliding seat to avoid being stuck or damaged by excessive force.

[0004] The principle of this device is that when it is reeled in to a certain extent, the load rises and lifts up the spherical protection block, thereby lifting the protection frame, and the support plate slides upward along the guide rod under the deformation of the spring, and then the conductive ring is separated from the two conductive sheets, so that the conductive sheet circuit is disconnected, but the angle between the protective cover and the winch wheel and other mechanisms is fixed, that is, after the winch is fixed to other machines, the angle of the protective cover is fixed accordingly, and in actual use, when the winch is fixed to different machines, in order to adapt to various machines, the fixed angle will also change. After the fixed angle of the above-mentioned device is changed, the angle of the protective cover will also change, and then the angle between the protective cover and the load will also change. The movement direction of the load is different from the movement of the protective cover, and then when the load contacts the spherical protection block, it is easy to get stuck, and the spherical protection block cannot be lifted normally, and the protection ball may even be damaged, which is not flexible enough to use.

[0005] Therefore, the present invention provides a crane winch protection device to solve the above problems. Summary of the invention

[0006] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a crane winch protection device, and the technical problem to be solved is: to provide a crane winch protection device that can be installed and used at various angles, so as to adapt to different machines and be flexible in use.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] A crane winch protection device comprises a fixed base, a motor is arranged on the fixed base, the motor is connected to a winch wheel, a traction rope is arranged on the winch wheel, and an anti-overwinding mechanism with an adjustable angle is arranged on the fixed base;

[0009] The anti-overwinding mechanism includes a fixing frame, a circular ring body is fixedly provided on the fixing frame, the circular ring body is parallel to the axial direction of the winch wheel, a connecting plate is slidably provided on the circular ring body, and the connecting plate can be fixed at different positions, the connecting plate is connected to a fixing plate, the fixing plate is elastically connected to a top plate on a side away from the connecting plate, a top rod is provided on a side of the top plate close to the fixing plate, the top rod passes through the fixing plate, and a first conductive layer and a first insulating layer are sequentially provided near the end, a rotating rod perpendicular to the top rod is slidably provided outside the top rod near the end, the rotating rod is coaxial with the circular ring body and can rotate around its axial direction, two first conductive sheets adapted to the first conductive layer are provided at the connection between the rotating rod and the top rod, the first conductive sheet is electrically connected to the motor, and rope holes are provided on the fixing plate and the top plate;

[0010] In the natural state, the first conductive layer of the top rod contacts with the two first conductive sheets of the rotating rod. When the relative position of the connecting plate and the annular body is changed, the rotating rod rotates, and the relative position with the top rod remains unchanged, so that the end of the traction rope passes through the rope holes of the fixed plate and the top plate in turn and is connected to the lifting object. When the lifting object contacts the top plate, the top plate is pushed closer to the fixed plate to move, driving the top rod to move. The top rod slides relative to the rotating rod, so that the first conductive layer is separated from the first conductive sheet, thereby disconnecting the circuit.

[0011] Preferably, the fixing frame is provided with a guide rope hole and two upper and lower guide rope wheels, and the guide rope wheels are parallel to the axis direction of the winch wheel.

[0012] Preferably, an auxiliary bracket is provided on one side of the fixed plate, the rotating rod is rotatably set on the auxiliary bracket, a slide rail is provided on the fixed base, the slide rail is parallel to the axial direction of the winch wheel, the fixed frame is slidably set on the slide rail, a vertical plate is provided on one end of the slide rail close to the motor, a telescopic tube is rotatably provided on the vertical plate, and is connected to the rotating rod through the telescopic tube, a connecting seat is provided on one end of the telescopic tube away from the rotating rod, and the connecting seat is electrically connected to the motor and the two first conductive sheets respectively.

[0013] Preferably, the conductive wire between the connecting base and the two first conductive sheets comprises a spring conductive wire segment.

[0014] Preferably, a protective device is provided on the rope hole of the fixing plate, and the protective device comprises a connecting block with a hollow structure, a rope guide tube is connected to the connecting block via a universal joint, and a plurality of balls are provided at one end of the rope guide tube away from the fixing plate.

[0015] Preferably, a first compression spring is provided at the first conductive sheet.

[0016] Preferably, an alarm mechanism is also included, which includes a baffle plate fixed relative to the rotating rod, the baffle plate is arranged at the end of the top rod away from the fixed plate, the baffle plate is provided with a groove on the side close to the top rod, two second conductive sheets are provided in the groove, and a second extrusion spring is provided at the second conductive sheet, and an alarm device electrically connected to the two second conductive sheets is provided on the side of the baffle plate away from the top rod, and a second insulating layer and a second conductive layer are provided in sequence at the end of the top rod close to the baffle plate. When the lifting object contacts the top plate, the top plate is pushed to move close to the fixed plate, driving the top rod to move, and the top rod slides relative to the rotating rod, so that the second conductive layer contacts the second conductive sheet, and the alarm device is controlled to alarm.

[0017] Preferably, the annular body is provided with a plurality of threaded fixing holes A, the connecting plate is provided with fixing holes B matched with the threaded fixing holes A, and the connecting plate and the annular body are fixed by threaded pins.

[0018] Preferably, a return spring is provided between the fixing plate and the top plate.

[0019] The beneficial effects of the present invention are:

[0020] When the present invention is actually used, the fixed base can be fixed to the machine at a certain angle according to the specific matching machine, so as to facilitate fixation. After the fixed base is fixed, the fixing position of the connecting plate and the annular body can be adjusted to adjust the angles of the fixed plate and the top plate to correspond to the direction of movement of the lifting object, and at the same time drive the rotating rod and the top rod to rotate synchronously, so that when the lifting object moves to contact with the top plate, it can smoothly push the top plate close to the fixed plate, drive the top rod to slide relative to the rotating rod, drive the first conductive sheet layer to separate from the first conductive sheet, thereby disconnecting the motor circuit and realizing overwinding prevention.

[0021] 2. The present invention can achieve angle adjustment by providing an anti-overwinding mechanism with adjustable angle, without adding other fixed structures, that is, only one fixed base is required, and the overall structure is compact and reasonable.

[0022] 3. When the first conductive sheet is disconnected through the first insulating layer or the second conductive sheet is disconnected through the second insulating layer, the present invention can shield the conductive ends of the first conductive sheet or the second conductive sheet, thereby preventing the two first conductive sheets or the two second conductive sheets from being connected when encountering water in rainy weather. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 It is a schematic diagram of the specific structure of the fixed base in the present invention;

[0025] Figure 3 It is a schematic diagram of the overall structure of the anti-overwinding mechanism in the present invention;

[0026] Figure 4 It is a schematic diagram of the connection between the fixed plate and the top plate in the present invention;

[0027] Figure 5 It is a schematic diagram of the connection between the fixing frame and two guide rope wheels in the present invention;

[0028] Figure 6 It is a schematic diagram of the connection between the top rod, the rotating rod and the baffle in the present invention;

[0029] Figure 7 It is a schematic structural diagram of the first conductive layer, the first insulating layer, the second conductive layer, and the second insulating layer on the top rod of the present invention;

[0030] Figure 8 It is a schematic diagram of the specific structure of the first conductive sheet and the first extrusion spring in the present invention;

[0031] Fig. 9 A schematic diagram of the specific structure of the second conductive sheet and the second extrusion spring in the present invention;

[0032] Fig.10 It is a schematic diagram of the present invention when a mounting angle is fixed;

[0033] Fig.11 It is a schematic diagram of the present invention when another installation angle is fixed.

[0034] In the figure: 1. fixed base, 2. motor, 3. winch wheel, 4. traction rope, 5. fixed frame, 6. slide rail, 7. auxiliary bracket, 8. telescopic tube, 9. connecting seat, 10. vertical plate, 11. guide rope hole, 12. guide rope wheel, 13. annular body, 14. rotating rod, 15. threaded fixing hole A, 16. fixed plate, 17. top plate, 18. ball, 19. guide rope tube, 20. connecting block, 21. connecting plate, 22. top rod, 221. first conductive layer, 222. first insulating layer, 223. second insulating layer, 224. second conductive layer, 23. threaded pin, 24. baffle, 25. alarm, 26. reset spring, 27. first conductive sheet, 28. first extrusion spring, 29. second conductive sheet, 30. second extrusion spring, 31. mounting surface. DETAILED DESCRIPTION

[0035] The following will refer to the attached Figures 1 to 11 The embodiments of the present invention are described in detail. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0036] A crane winch protection device, as shown in the attached Figure 1 , Figure 2 As shown, it includes a fixed base 1, which is composed of four C-shaped steels at the front, rear, left and right. A positioning hole for fixing is opened on the C-shaped bar. It has a simple structure and strong bearing capacity. A motor 2 is arranged on the fixed base 1, and the motor 2 is connected to a winch wheel 3. The winch wheel 3 is provided with a traction rope 4. The above structure constitutes a winch. This part of the structure is the existing technology and will not be described in detail here. An anti-overwinding mechanism with an adjustable angle is arranged on the front side C-shaped steel of the fixed base 1.

[0037] like Figure 3 , Figure 4 As shown, the overwinding prevention mechanism includes a fixing frame 5, which is in a "C" shape. A circular ring body 13 is fixedly provided on the left side of the fixing frame 5 near the front side. The circular ring body 13 is parallel to the axial direction of the winch wheel 3, that is, both are along the left and right directions. A connecting plate 21 is slidably provided on the circular ring body 13, and the connecting plate 21 can be fixed at different positions. In this embodiment, the circular ring body 13 is provided with upper, lower and front three threaded fixing holes A15, and the connecting plate 21 is provided with fixing holes B that are compatible with the threaded fixing holes A15. The connecting plate 21 is fixed to the circular ring body 13 by a threaded pin 23, and the position of the connecting plate 21 is adjusted by the upper, lower and front three threaded fixing holes A15.

[0038] The connecting plate 21 is connected to the fixing plate 16. In the present embodiment, the fixing plate 16 is arranged at the end of the connecting plate 21 away from the annular body 13 and is perpendicular to the connecting plate 21. The fixing plate 16 is elastically connected to the top plate 17 on the side away from the connecting plate 21. In the present embodiment, a return spring 26 is provided between the fixing plate 16 and the top plate 17, and the top plate 17 is moved away from the fixing plate 16 by the return spring 26. A push rod 22 is provided on the side of the top plate 17 close to the fixing plate 16. The push rod 22 passes through the fixing plate 16 and is slidably connected to the fixing plate 16.

[0039] This embodiment can be used to make adjustments when secured to a vertical or horizontal surface of a machine.

[0040] like Figure 3 , Figure 4 , Figure 6 , Figure 7 , Figure 8As shown, the top rod 22 is provided with a first conductive layer 221 and a first insulating layer 222 in sequence near the end, that is, the first conductive layer 221 is away from the fixed plate 16 relative to the first insulating layer 222, and a rotating rod 14 perpendicular to the top rod 22 is slidably provided outside the end of the top rod 22. The rotating rod 14 is coaxial with the annular body 13 and can rotate around its axis. Two first conductive sheets 27 adapted to the first conductive layer 221 are provided at the connection between the rotating rod 14 and the top rod 22. The first conductive sheet 27 is electrically connected to the motor 2. The first conductive layer 221 and the first conductive sheet 27 are connected or disconnected by the sliding movement of the top rod 22 relative to the rotating rod 14. Rope holes are provided on the fixed plate 16 and the top plate 17.

[0041] Working principle: In the natural state, under the action of the return spring 26, the top plate 17 moves away from the fixed plate 16. At this time, the first conductive layer 221 on the top rod 22 contacts the two first conductive sheets 27 on the rotating rod 14, and the two first conductive sheets 27 are connected, and the motor 2 is in the on state. When the position of the connecting plate 21 and the annular body 13 is adjusted, the connecting plate 21 drives the angle of the fixed plate 16, the top plate 17 and the top rod 22 to change, and the top rod 22 drives the rotating rod 14 to rotate. The first conductive layer 221 and the two first conductive sheets 27 on the rotating rod 14 still maintain contact. When the top plate 17 approaches the fixed plate 16, it drives the top rod 22 to move, so that the top rod 22 and the rotating rod 14 are relatively guided, so that the first conductive layer 221 is separated from the two first conductive sheets 27, the two first conductive sheets 27 are disconnected, and the motor 2 is disconnected.

[0042] During specific operation, according to the actual machine used, the device is fixed to the mounting surface 31 of the machine through the fixed bottom plate 1, and then the fixed position of the connecting plate 21 is adjusted so that its position corresponds to the moving direction of the lifting object. For details, please refer to Fig.10 , Fig.11 As shown, when the mounting surface 31 is vertical or at the top, it can be flexibly adjusted. After adjustment or in advance, the end of the traction rope 4 is passed through the fixed plate 16 and the top plate 17 in sequence to connect with the lifting object, and the motor 2 is controlled to rotate to start working. When the lifting object pushes the top plate 17 to move a certain distance, the motor 2 is automatically disconnected to prevent overwinding.

[0043] In addition, it should be noted that Figure 1 , Figure 3 , Figure 4 As shown, in order to balance the force, in this embodiment, an auxiliary circular ring body, an auxiliary connecting plate 21, an auxiliary push rod, and an auxiliary reset spring are symmetrically provided on the right side of the fixing frame 5 near the front side, with the circular ring body 13, the connecting plate 21, the push rod 22, and the reset spring 26. The symmetrical design ensures reasonable force.

[0044] like Figure 1 , Figure 3 , Figure 5 As shown, in this embodiment, the fixing frame 5 is provided with a guide rope hole 11 and two upper and lower guide rope wheels 12, the guide rope wheel 12 is parallel to the axial direction of the winch wheel 3, and the traction rope 4 is fixed to the lifting object through the guide rope hole 11, the guide rope wheel 12, the fixing plate 16 and the top plate 17 in sequence. When the connecting plate 21 is adjusted, the traction rope 4 can be supported by different guide rope wheels 12 to reduce friction and protect the traction rope 4 body. For details, please refer to Fig.10 , Fig.11 As shown, when the mounting surface 31 is a vertical or horizontal plane, the traction rope 4 can be slidably supported by different guide rope wheels 12 .

[0045] like Figure 1 , Figure 3 , Figure 4 , Figure 5 As shown, an auxiliary bracket 7 is provided on one side of the fixed frame 5, and a rotating rod 14 is rotatably set on the auxiliary bracket 7 so that it can rotate around the axial direction of the annular body 13. A slide rail 6 is provided on the fixed base 1, and the slide rail 6 is parallel to the axial direction of the winch wheel 3, that is, along the left and right direction, the fixed frame 5 is slidably set on the slide rail 6, and a vertical plate 10 is provided at one end of the slide rail 6 close to the motor 2. A telescopic tube 8 is rotatably provided on the vertical plate 10, which is connected to the rotating rod 14 through the telescopic tube 8. A connecting seat 9 is provided at one end of the telescopic tube 8 away from the rotating rod 14, and the connecting seat 9 is electrically connected to the motor 2 and the two first conductive sheets 27 respectively.

[0046] Working principle: When the traction rope 4 is retracted or released, the fixing frame 5 can move with the traction rope 4, reducing the pressure between the traction rope 4 and the fixing frame 5, thereby protecting the traction rope 4 body, and protecting the internal guide through the telescopic tube 8. The connecting seat 9 is close to the motor 2, and the wires between the two are also convenient to arrange.

[0047] like Figure 1 , Figure 8 As shown, the conductor between the connection base 9 and the two first conductive sheets 27 includes a spring conductor segment. Specifically, the portion inside the telescopic tube 8 is the spring conductor segment.

[0048] Working principle: When the telescopic tube 8 is extended or retracted, the inside of the telescopic tube 8 can be stretched or contracted regularly, which can effectively prevent the wire from being entangled.

[0049] like Figure 1 , Figure 3 As shown, a protective device is provided on the rope hole of the fixed plate 16 , and the protective device includes a connecting block 20 with a hollow structure. A rope guide tube 19 is connected to the connecting block 20 through a universal joint. A plurality of balls 18 are provided at one end of the rope guide tube 19 away from the fixed plate 16 .

[0050] Working principle: the traction rope 4 passes through the guide rope tube 19 and is supported by the sliding ball 18, so as to protect the traction rope 4 body, and the guide rope tube 19 can be connected to the connecting block 20 through a universal joint and can move flexibly. When lifting, when the load shakes, the guide rope tube 19 can be flexibly adjusted with the shaking of the traction rope 4.

[0051] like Figure 6 , Figure 8 As shown, a first extrusion spring 28 is provided at the first conductive sheet 27. Specifically, a hole for connecting with the top rod 22 is opened on the rotating rod 14, and two first conductive sheets 27 are provided in the hole. The first conductive sheets 27 can be set to a certain sliding position to slide on the side wall of the hole, and a cavity is provided in the rotating rod 14, and the sliding member penetrates into the cavity. A first extrusion spring 28 connected to the sliding member is provided in the cavity, which generates a thrust on the first conductive sheet 27, so that the two first conductive sheets 27 are close to each other, thereby ensuring close contact with the first conductive layer 221 and ensuring circuit connection.

[0052] like Figure 3 , Figure 6 , Figure 7 , Figure 8 , Fig. 9 As shown, an alarm mechanism is also included, which includes a baffle 24 fixed relative to the rotating rod 14, the baffle 24 is arranged at the end of the top rod 22 away from the fixed plate 16, and a groove is opened on the side of the baffle 24 close to the top rod 22, in which two second conductive sheets 29 are arranged, and a second extrusion spring 30 is arranged at the second conductive sheet 29. The specific structure is similar to the structure of the first conductive sheet 27 and the first extrusion spring 28, and is not described in detail here. An alarm 25 electrically connected to the two second conductive sheets 29 is provided on the side of the baffle 24 away from the top rod 22, and a second insulating layer 223 and a second conductive layer 224 are provided in sequence at one end of the top rod 22 close to the baffle 24, that is, the second insulating layer 223, the second conductive layer 224, the first conductive layer 221, and the first insulating layer 222 are arranged in sequence from one end of the top rod 22 close to the baffle 24 to the other end.

[0053] Working principle: When the lifting object contacts the top plate 17, the top plate 17 is pushed to move closer to the fixed plate 16, driving the top rod 22 to move. The top rod 22 slides relative to the rotating rod 14, so that the second conductive layer 224 contacts the second conductive sheet 29, and the control alarm 25 sounds an alarm. As the top rod 22 continues to move until the first conductive layer 221 is separated from the two first conductive sheets 27, the motor 2 stops working and the alarm 25 sounds an alarm, which also plays a role in preventing overwinding and providing a reminder.

[0054] In addition, in the present invention, when the first conductive sheet 27 is disconnected by the first insulating layer 222 or when the second conductive sheet 29 is disconnected by the second insulating layer 223, it can shield the conductive ends of the first conductive sheet 27 or the second conductive sheet 29, thereby preventing the two first conductive sheets 27 or the two second conductive sheets 29 from being connected when encountering water in rainy weather.

[0055] It should be noted that in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0056] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A crane winch protection device, comprising a fixed base (1), a motor (2) being arranged on the fixed base (1), the motor (2) being connected to a winch wheel (3), the winch wheel (3) being provided with a traction rope (4), characterized in that: The fixed base (1) is provided with an anti-overwinding mechanism with an adjustable angle; The anti-overwinding mechanism comprises a fixing frame (5), a circular ring body (13) is fixedly provided on the fixing frame (5), the circular ring body (13) is parallel to the axis direction of the winch wheel (3), a connecting plate (21) is slidably provided on the circular ring body (13), and the connecting plate (21) can be fixed at different positions, the connecting plate (21) is connected to a fixing plate (16), a side of the fixing plate (16) away from the connecting plate (21) is elastically connected to a top plate (17), a side of the top plate (17) close to the fixing plate (16) is provided with a top rod (22), and the top rod (22) passes through the fixing plate (16), and a first conductive layer (221) and a first insulating layer (222) are sequentially provided near the end, a rotating rod (14) perpendicular to the top rod (22) is slidably provided outside the top rod (22) near the end, the rotating rod (14) is coaxial with the annular body (13) and can rotate around its axis, two first conductive sheets (27) adapted to the first conductive layer (221) are provided at the connection between the rotating rod (14) and the top rod (22), the first conductive sheets (27) are electrically connected to the motor (2), and rope holes are provided on the fixed plate (16) and the top plate (17); In a natural state, the first conductive layer (221) of the top rod (22) contacts the two first conductive sheets (27) of the rotating rod (14). When the relative position of the connecting plate (21) and the annular body (13) is changed, the rotating rod (14) rotates, and the relative position with the top rod (22) remains unchanged, so that the end of the traction rope (4) passes through the rope holes of the fixed plate (16) and the top plate (17) in sequence and is connected to the lifting object. When the lifting object contacts the top plate (17), the top plate (17) is pushed to move closer to the fixed plate (16), driving the top rod (22) to move. The top rod (22) slides relative to the rotating rod (14), so that the first conductive layer (221) is separated from the first conductive sheet (27), and the circuit is disconnected; It also includes an alarm mechanism, the alarm mechanism comprising a baffle (24) fixed relative to the rotating rod (14), the baffle (24) being arranged at one end of the top rod (22) away from the fixed plate (16), a groove being provided on one side of the baffle (24) close to the top rod (22), two second conductive sheets (29) being provided in the groove, a second extrusion spring (30) being provided at the second conductive sheet (29), an alarm (25) being electrically connected to the two second conductive sheets (29) being provided on one side of the baffle (24) away from the top rod (22), a second insulating layer (223) and a second conductive layer (224) being provided in sequence at one end of the top rod (22) close to the baffle (24), when the lifting object contacts the top plate (17), the top plate (17) is pushed to move close to the fixed plate (16), driving the top rod (22) to move, the top rod (22) slides relative to the rotating rod (14), causing the second conductive layer (224) to contact the second conductive sheet (29), and controlling the alarm (25) to sound an alarm; The annular body (13) is provided with a plurality of threaded fixing holes A (15), the connecting plate (21) is provided with fixing holes B adapted to the threaded fixing holes A (15), and the connecting plate (21) and the annular body (13) are fixed by means of threaded pins (23).

2. A crane winch protection device according to claim 1, characterized in that: The fixing frame (5) is provided with a rope guide hole (11) and two upper and lower rope guide wheels (12), and the rope guide wheels (12) are parallel to the axis direction of the winch wheel (3).

3. A crane winch protection device according to claim 1, characterized in that: An auxiliary bracket (7) is provided on one side of the fixed frame (5), the rotating rod (14) is rotatably mounted on the auxiliary bracket (7), a slide rail (6) is provided on the fixed base (1), the slide rail (6) is parallel to the axial direction of the winch wheel (3), the fixed frame (5) is slidably mounted on the slide rail (6), a vertical plate (10) is provided at one end of the slide rail (6) close to the motor (2), a telescopic tube (8) is rotatably mounted on the vertical plate (10), and is connected to the rotating rod (14) via the telescopic tube (8), a connecting seat (9) is provided at one end of the telescopic tube (8) away from the rotating rod (14), and the connecting seat (9) is electrically connected to the motor (2) and the two first conductive sheets (27) respectively.

4. A crane winch protection device according to claim 3, characterized in that: The conductive wire between the connection seat (9) and the two first conductive sheets (27) comprises a spring conductive wire segment.

5. A crane winch protection device according to claim 1, characterized in that: A protective device is provided on the rope hole of the fixing plate (16), the protective device comprising a connecting block (20) with a hollow structure, a rope guide tube (19) being connected to the connecting block (20) via a universal joint, and a plurality of balls (18) being provided at one end of the rope guide tube (19) away from the fixing plate (16).

6. A crane winch protection device according to claim 1, characterized in that: A first pressing spring (28) is provided at the first conductive sheet (27).

7. A crane winch protection device according to claim 1, characterized in that: A return spring (26) is provided between the fixing plate (16) and the top plate (17).

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