Limiting device for heavy hammer of lifting appliance

Abstract

The invention provides a lifting appliance heavy hammer limiting device. The lifting appliance heavy hammer limiting device comprises a triggering mechanism, a heavy hammer mechanism, a platform, a guide mechanism, an anti-swing mechanism, a height detector and a lifting appliance. The trigger mechanism is fixed on a platform of the crane, the guide mechanism is used for guiding the heavy hammer mechanism, the anti-swing mechanism is connected with the guide mechanism and the platform, the height detector is fixed at the lower end of the guide mechanism, and the lifting appliance is positioned below the device; a spring is arranged in the triggering mechanism and the triggering speed is increased through elastic force; the guide mechanism can enable the counter weight mechanism to accurately trigger the limit switch; the anti-swing mechanism prevents the guide mechanism from swinging and has an anti-falling function; the height detector is provided with an early warning value, when the height of the lifting appliance reaches the early warning value, the limiting switch can be triggered, the lifting power source is disconnected, and the lifting appliance is prevented from rushing against the platform. The problems that under the working conditions of high lifting height, large wind load and vibration, a traction steel wire is prone to being wound, an ejector rod is prone to being clamped, a device falls to hurt people, and the response is slow are solved, and the lifting appliance is prevented from impacting the top platform rapidly, effectively and accurately.

Description

Technical Field

[0001] The invention belongs to the field of limit devices and safety technology, and in particular relates to a limit device for a heavy hammer of a sling. Background Art

[0002] The sling is a device for picking up objects on some special cranes. In the normal use of the crane, in order to ensure the safety of use and prevent the sling from hitting the top and causing safety accidents, it is usually necessary to install a sling anti-hitting device on the crane. At present, the anti-hitting devices installed on the crane mainly include: heavy hammer type, fork type, side pressure type, etc. The heavy hammer limiter of the present invention refers to the heavy hammer type. In the actual application of preventing the sling from hitting the top, the heavy hammer type is mostly used, but the traction wire of this structural form is easy to be entangled with the lifting wire rope of the crane, resulting in the failure of the heavy hammer limiter function. For the working conditions where the lifting height of the sling is high and there are large wind loads and vibrations, the heavy hammer type with traction wire alone is used. The traction wire is easy to be entangled with the lifting wire rope, and the heavy hammer itself is heavy and easily affected by vibration, swinging, resulting in a decrease in the reliability of the device. In order to avoid entanglement, some heavy hammer types use a top rod instead of the traction wire. At this time, the top rod is long and easy to bend and get stuck under force, and the heavy hammer limiter function fails. Usually the lower end of the heavy hammer limit device is suspended in the air, which may injure people and cause personal accidents when it falls. The lifting device has a fast top speed, so the device response time is particularly important. Failure to respond in time can easily cause safety accidents.

[0003] Chinese utility model patent CN210528294U discloses a crane heavy hammer lifting limit device. It includes a heavy hammer hanging frame, a crank, a counterweight, a travel switch, etc. The utility model patent adopts a heavy hammer hanging frame, which is connected to the crank through a traction wire, and there is a counterweight at the other end of the crank. During operation, the sling rises, lifts the heavy hammer hanging frame, and the heavy hammer counterweight presses down the travel switch by its own gravity, the equipment is powered off, and the sling stops rising. However, the utility model patent does not take into account that when the crane is moving, the heavy hammer hanging frame connected with the traction wire and the crank is prone to swing, resulting in accidental contact, and the traction wire is broken, which is prone to falling objects from high altitude and injuring people. At the same time, due to the swing, it is difficult for the sling to accurately lift the heavy hammer hanging frame, resulting in the failure of the heavy hammer limit function. The elasticity of the traction wire makes it possible for it to stretch suddenly when subjected to external force, so that the traction wire is easy to entangle after relaxation, resulting in the failure of the heavy hammer limit function.

[0004] Chinese utility model patent CN215946531U discloses a weight limit device for a lifting device. It includes a limit switch, a weight, and a guide device. This utility model patent uses a push rod to directly trigger the limit switch, and limits the hammer rod through a limit rod and a limit plate. During operation, the sling rises and hits the weight, and the hammer rod rises to trigger the limit switch, controlling the sling to stop rising. However, this utility model patent does not take into account the large inertia and impact of the sling rising, and directly using the push rod to trigger the limit switch may easily damage the limit switch. Using the push rod as a whole will cause the push rod to be too long, and the possibility of bending under stress will increase. The guide device is only fixed by a fixed plate, and has poor seismic resistance. It is easy to bend when subjected to stress, causing the push rod to get stuck and the device to fail.

[0005] Chinese utility model patent CN219341506U discloses a lifting limit protection device for a bridge crane grab bucket. It includes a platform, a weight limit switch, a connecting rod, a mandrel, a traction wire, a limit ring, a proximity switch, etc. This utility model patent adopts a mandrel and a traction wire combination, with a connecting rod to fix the mandrel, a limit ring to constrain the swing of the mandrel, and a proximity switch to play a limit protection role. During operation, the spreader rises, touches and lifts the mandrel, and the pulling force on the traction wire by the mandrel is reduced, triggering the weight limit switch to control the spreader to stop rising; when the spreader is close to the hammer head of the mandrel, the proximity switch is activated first to control the spreader to stop rising. However, the utility model patent does not take into account that the elasticity of the traction wire may cause it to suddenly stretch when subjected to external force, making it easy for the traction wire to tangle after relaxation, resulting in the failure of the triggering weight limit switch function. This problem is less likely to occur if the wire rope is kept straight. At the same time, the utility model patent uses a connecting rod to fix the top rod in the air to form a cantilever beam structure, which has poor force performance. Under the inertia of the crane movement, the connecting rod is prone to large deformation and bending, causing the top rod to get stuck, causing the triggering weight limit switch function to fail. Moreover, the cantilever beam structure has poor integrity, and the connection between the platform and the connecting rod is prone to breakage. The top rod and the hammer head are heavy. Once they break and fall, they are prone to safety accidents. Summary of the invention

[0006] In order to solve the existing problems, the team of Changsha University of Science and Technology and the team of Hunan China Railway No. 5 New Heavy Industry Co., Ltd. cooperated to propose a hoist weight limit device, which is used to solve the problems of the traction wire of the weight limit device being easily entangled, the top rod being easily stuck, and the possible falling and injuring people under the working conditions of high lifting height, large wind load and vibration, and the speed of the hoist rushing to the top being too fast and the device reacting slowly. The reliability and safety of the weight limit device are improved, the probability of safety accidents is reduced, and the property and personal safety of users are protected. The present invention makes the weight of the top rod much greater than the weight to make the traction wire straight in the normal state, and then the traction wire continues to be straight during operation through the elastic force of the spring, reducing the possibility of the traction wire suddenly being slack and entangled with the lifting wire, thereby improving the reliability of the device. The anti-sway wire fixing guide mechanism is adopted to form a cantilever structure with inclined tension, disperse the load, improve the seismic resistance of the structure, effectively improve the stability and bearing capacity of the device, and reduce the possibility of the top rod getting stuck. At the same time, the anti-sway mechanism also provides the device with an anti-fall function. The spring force is used to accelerate the weight to fall, thereby triggering the limit switch as soon as possible and disconnecting the lifting power supply. The height detector is used to detect the height of the hoist. When the warning height is reached, the limit switch is triggered and the lifting power supply of the hoist is disconnected.

[0007] The present invention provides a heavy hammer limiting device for a sling in detail.

[0008] In order to achieve the above-mentioned object, the present invention provides a weight limit device for a crane sling, which mainly includes: a trigger mechanism, a weight mechanism, a platform, a guide mechanism, an anti-sway mechanism, a height detector and a sling. The trigger mechanism is fixed to the platform by bolts, the guide mechanism is used to guide the weight mechanism, the anti-sway mechanism connects the guide mechanism and the platform and prevents the guide mechanism from swinging, the height detector is fixed to the lower end of the guide mechanism, and the sling is located below the device.

[0009] The trigger mechanism includes a limit switch, a limit bracket, a guide frame, a box, a spring seat, a spring and a box cover. The limit switch is installed on the platform, and the limit bracket is fixed on the box. The guide frame is installed in the box and supported by the limit bracket. The box and the box cover are connected by bolts, and the box is also connected to the platform by bolts. The spring seat is fixed on the lower surface of the box cover, and the spring is installed in the spring seat. The spring is usually compressed by a weight, and elastically recovers during operation, accelerating the falling of the weight, thereby triggering the limit switch as soon as possible and disconnecting the lifting power of the sling.

[0010] The weight mechanism includes a weight, a traction wire, a limit plate, a push rod and a rod head. The rod head is fixed to the push rod with bolts, and the limit plate is welded to the push rod. The two ends of the traction wire are connected to the weight and the push rod respectively. The weight of the push rod is much greater than that of the weight, so that the traction wire is usually straight and the spring is compressed.

[0011] The guide mechanism includes a pulley, a bracket, a mounting plate, an upper guide sleeve, an upper flange, a lower flange and a lower guide sleeve. The bracket is fixed on the platform, and the pulley is mounted on the bracket. The upper flange and the lower flange are welded to the upper guide sleeve and the lower guide sleeve respectively, and the upper flange and the lower flange are connected by bolts. The mounting plate is welded to the upper guide sleeve and fixed to the platform by bolts.

[0012] The anti-sway mechanism includes a fixed block and an anti-sway steel wire. The fixed block is installed on the platform and connected to the lower guide sleeve through the anti-sway steel wire. Multiple anti-sway steel wires pull the lower guide sleeve and restrain each other, so that the lower guide sleeve will not swing, thereby improving the reliability of the device triggering.

[0013] The guide frame guides the weight to fall, and the bottom diameter of the weight is larger than the diameter of the middle hole of the limit bracket. After the weight falls, it is supported by the limit bracket to prevent the limit switch from being directly crushed.

[0014] The traction wire is easily broken due to stress concentration at both ends. If it breaks, since the diameter of the limit plate is larger than the diameter of the middle through hole of the upper flange, the push rod will be stuck by the upper flange and will not fall and cause casualties.

[0015] The parts of the weight mechanism, the guide mechanism and the anti-sway mechanism under the platform can be all lifted out of the holes of the platform by unscrewing the bolts on the mounting plate, so as to facilitate maintenance.

[0016] The working principle of the spreader weight limit device is that when the spreader rises, it touches and lifts the weight mechanism, the weight of the weight mechanism falls, the limit switch of the trigger mechanism is triggered, and the lifting power of the spreader can be disconnected, and the spreader stops rising immediately. At the same time, the spreader rises and approaches the height detector, and the height detector receives a signal. When the spreader height value reaches the warning value, it can also trigger the limit switch to disconnect the lifting power of the spreader. The double protection measures prevent the spreader from hitting the top platform.

[0017] Compared with the prior art, the above-mentioned lifting equipment weight limiting device has the following beneficial effects.

[0018] ① High reliability. By making the deadweight of the top rod much greater than the weight, the wire rope is stretched straight under normal conditions, and the traction wire is kept stretched straight during operation by the spring force, which reduces the possibility of the traction wire suddenly becoming loose and entangled; an anti-sway mechanism is used to enhance the anti-seismic ability of the device. The reliability of the device is improved based on the above two methods.

[0019] ②Good safety. When the traction wire breaks, the limit plate will lock the push rod at the upper flange, and the anti-sway wire will pull the lower guide sleeve to prevent the push rod, lower guide sleeve and related components from falling.

[0020] ③ Fast response speed. A spring is added to the trigger mechanism. The spring is usually in a compressed state. When working, it recovers elastically and accelerates the falling of the heavy hammer, thereby triggering the limit switch as soon as possible, improving the response speed of the trigger mechanism.

[0021] ④ Strong applicability. The anti-sway mechanism enhances the device's anti-seismic ability and strong environmental adaptability. The guide sleeve adopts a segmented type, and the installation method mostly uses bolts, which is easy to disassemble and assemble, and occupies a small length space during transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 yes Figure 1 Schematic diagram of the trigger mechanism structure;

[0024] Figure 3 yes Figure 1 Schematic diagram of the heavy hammer mechanism structure;

[0025] Figure 4 yes Figure 1 Schematic diagram of the guiding mechanism structure;

[0026] Figure 5 yes Figure 1 Schematic diagram of the anti-sway mechanism structure;

[0027] Figure 6 It is a schematic diagram of the working state of the present invention.

[0028] above Figures 1 to 6 The markings are: 1. Trigger mechanism, 1-1. Limit switch, 1-2. Limit bracket, 1-3. Guide frame, 1-4. Box body, 1-5. Spring seat, 1-6. Spring, 1-7. Box cover; 2. Weight mechanism, 2-1. Weight, 2-2. Traction wire, 2-3. Limit plate, 2-4. Push rod, 2-5. Push rod head; 3. Platform; 4. Guide mechanism, 4-1. Pulley, 4-2. Bracket, 4-3. Mounting plate, 4-4. Upper guide sleeve, 4-5. Upper flange, 4-6. Lower flange, 4-7. Lower guide sleeve; 5. Anti-sway mechanism, 5-1. Fixing block, 5-2. Anti-sway wire; 6. Height detector; 7. Lifting device. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0030] In the description of the present application, it should be understood that the terms "middle", "diameter", "height", "up", "down", "front", "back", "left", "right", "vertical", "top", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the description of the present application, the meaning of "four" refers to the number of anti-sway wires required for the stability of the device, which can be three, five, six, etc.

[0032] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0034] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0035] The present invention discloses a heavy hammer limit device for a sling, which is composed of a trigger mechanism 1, a heavy hammer mechanism 2, a platform 3, a guide mechanism 4, an anti-sway mechanism 5, a height detector 6 and a sling 7. The trigger mechanism 1 includes: a limit switch 1-1, a limit bracket 1-2, a guide bracket 1-3, a box body 1-4, a spring seat 1-5, a spring 1-6 and a box cover 1-7. The heavy hammer mechanism 2 includes: a heavy hammer 2-1, a traction wire 2-2, a limit plate 2-3, a push rod 2-4 and a push rod head 2-5. The guide mechanism 4 includes: a pulley 4-1, a bracket 4-2, a mounting plate 4-3, an upper guide sleeve 4-4, an upper flange 4-5, a lower flange 4-6 and a lower guide sleeve 4-7. The anti-sway mechanism 5 includes a fixed block 5-1 and an anti-sway wire 5-2. The height detector 6 can receive a signal of the sling rising, and when the sling height value reaches the warning value, the limit switch is triggered.

[0036] In this embodiment, preferably, the trigger mechanism 1 is fixed to the platform 3 by bolts, the guide mechanism 4 is used to guide the weight mechanism 2, the anti-sway mechanism 5 connects the guide mechanism 4 and the platform 3 and prevents the guide mechanism 4 from swinging, the height detector 6 is fixed at the lower end of the guide mechanism 4, and the sling 7 is located below the device.

[0037] In this embodiment, preferably, the limit switch 1-1 is installed on the platform 3, and the limit bracket 1-2 is fixed on the box 1-4. The guide frame 1-3 is installed in the box 1-4 and supported by the limit bracket 1-2. The box 1-4 and the box cover 1-7 are connected by bolts, and at the same time, the box 1-4 is connected to the platform 3 by bolts, which is convenient for disassembly and assembly. The spring seat 1-5 is fixed on the lower surface of the box cover 1-7. The spring seat 1-5 is fixed on the lower surface of the box cover 1-7, and the spring 1-6 is installed in the spring seat 1-5. The spring 1-6 is usually compressed by the weight 2-1, and elastically recovers during operation, accelerating the falling of the weight 2-1, thereby triggering the limit switch 1-1 as soon as possible, disconnecting the lifting power supply of the sling 7 to prevent the sling 7 from hitting the top platform 3, and improving the response speed of the trigger mechanism 1.

[0038] In this embodiment, preferably, the rod head 2-5 is connected to the top rod 2-4 with bolts, and the limit plate 2-3 is welded to the top rod 2-4. The two ends of the traction wire 2-2 are connected to the weight 2-1 and the top rod 2-4 respectively. The weight of the top rod 2-4 is much greater than the weight 2-1, so that the traction wire 2-2 is usually straight and the spring 1-6 is compressed. The gravitational potential energy is converted into elastic potential energy and stored in the spring 1-6, which is released during operation, so as to keep the traction wire 2-2 straight and avoid winding.

[0039] In this embodiment, preferably, the bracket 4-2 is fixed on the platform 3, and the pulley 4-1 is installed on the bracket (4-2). The upper flange 4-5 and the lower flange 4-6 are welded to the upper guide sleeve 4-4 and the lower guide sleeve 4-7 respectively, and the upper flange 4-5 and the lower flange 4-6 are connected by bolts. The mounting plate 4-3 is welded to the upper guide sleeve 4-4 and fixed to the platform 3 by bolts. The segmented type is adopted, and the length space occupied by the guide mechanism 4 during transportation is small.

[0040] In this embodiment, preferably, the fixing block 5-1 is installed on the platform 3 and connected to the lower guide sleeve 4-7 through the anti-sway wire 5-2. The four anti-sway wires 5-2 pull the lower guide sleeve 4-7 and restrain each other, so that the lower guide sleeve 4-7 will not swing, thereby improving the reliability of the device triggering. At the same time, it prevents the lower guide sleeve 4-7 and related components from falling, thereby improving the safety of the device.

[0041] In this embodiment, preferably, the guide frame 1-3 guides the weight 2-1 to fall, and the bottom diameter of the weight 2-1 is larger than the diameter of the middle hole 1-2-1 of the limit bracket 1-2. After the weight 2-1 falls, it is supported by the limit bracket 1-2, thereby preventing the limit switch 1-1 from being directly crushed and reducing property losses.

[0042] In this embodiment, preferably, the traction wire 2-2 is easily broken due to stress concentration at both ends. If it breaks, since the diameter of the limit plate 2-3 is larger than the diameter of the middle through hole of the upper flange 4-5, the top rod 2-4 will be stuck by the upper flange 4-5, so it will not fall and cause casualties.

[0043] In this embodiment, preferably, the parts of the weight mechanism 2, the guide mechanism 4, and the anti-sway mechanism 5 below the platform 3 can be all lifted out of the holes of the platform 3 by unscrewing the bolts on the mounting plate 4-3, so as to facilitate maintenance.

[0044] In this embodiment, preferably, the working principle of the sling weight limit device is that when the sling 7 rises and touches and lifts the weight mechanism 2, the weight 2-1 of the weight mechanism 2 falls, and the limit switch 1-1 of the trigger mechanism 1 is triggered, which can disconnect the lifting power of the sling 7, and the sling 7 stops rising immediately. At the same time, the sling 7 rises and approaches the height detector 6. The height detector 6 receives a signal. When the height value of the sling 7 reaches the warning value, the limit switch 1-1 can also be triggered to disconnect the lifting power of the sling 7. The double protection measures prevent the sling 7 from hitting the top platform 3.

[0045] The contents explained in the above embodiments should be understood as these embodiments are only used to more clearly illustrate the present invention, and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

Claims

1. A heavy hammer limit device for a sling, characterized in that: The device comprises a trigger mechanism (1), a weight mechanism (2), a platform (3), a guide mechanism (4), an anti-sway mechanism (5), a height detector (6) and a sling (7); the trigger mechanism (1) is fixed to the platform (3) of the crane by bolts, the guide mechanism (4) is used to guide the weight mechanism (2), the anti-sway mechanism (5) connects the guide mechanism (4) and the platform (3) and prevents the guide mechanism (4) from swinging, the height detector (6) is fixed to the lower end of the guide mechanism (4), and the sling (7) is located below the device.

2. The heavy hammer limit device for a sling according to claim 1, characterized in that: The trigger mechanism (1) comprises a limit switch (1-1), a limit bracket (1-2), a guide bracket (1-3), a box (1-4), a spring seat (1-5), a spring (1-6) and a box cover (1-7); the limit switch (1-1) is mounted on a platform (3); the limit bracket (1-2) is fixed on the box (1-4); the guide bracket (1-3) is mounted in the box (1-4) and supported by the limit bracket (1-2); the box ( The box body (1-4) and the box cover (1-7) are connected by bolts, and at the same time, the box body (1-4) is connected to the platform (3) by bolts; the spring seat (1-5) is fixed on the lower surface of the box cover (1-7), and the spring (1-6) is installed in the spring seat (1-5); the spring (1-6) is usually compressed by the weight (2-1), and elastically recovers during operation, accelerating the falling of the weight (2-1), thereby triggering the limit switch (1-1) as soon as possible and disconnecting the lifting power supply of the sling (7).

3. A lifting equipment weight limiter according to claim 1, characterized in that: The weight mechanism (2) comprises a weight (2-1), a traction wire (2-2), a limit plate (2-3), a push rod (2-4) and a rod head (2-5); the rod head (2-5) is connected to the push rod (2-4) by bolts, and the limit plate (2-3) is welded to the push rod (2-4); the two ends of the traction wire (2-2) are respectively connected to the weight (2-1) and the push rod (2-4), and the weight of the push rod (2-4) is much greater than that of the weight (2-1), so that the traction wire (2-2) is usually straight and the spring (1-6) is compressed.

4. A lifting equipment weight limiter according to claim 1, characterized in that: The guide mechanism (4) comprises a pulley (4-1), a bracket (4-2), a mounting plate (4-3), an upper guide sleeve (4-4), an upper flange (4-5), a lower flange (4-6) and a lower guide sleeve (4-7); the bracket (4-2) is fixed on the platform (3), and the pulley (4-1) is mounted on the bracket (4-2); the upper flange (4-5) and the lower flange (4-6) are respectively welded to the upper guide sleeve (4-4) and the lower guide sleeve (4-7), and the upper flange (4-5) and the lower flange (4-6) are connected by bolts; the mounting plate (4-3) is welded to the upper guide sleeve (4-4) and fixed to the platform (3) by bolts.

5. The heavy hammer limit device for a sling according to claim 1, characterized in that: The anti-sway mechanism (5) comprises a fixed block (5-1) and an anti-sway steel wire (5-2); the fixed block (5-1) is mounted on the platform (3) and connected to the lower guide sleeve (4-7) via the anti-sway steel wire (5-2); a plurality of anti-sway steel wires (5-2) pull the lower guide sleeve (4-7) and restrain each other, so that the lower guide sleeve (4-7) does not swing, thereby improving the reliability of device triggering.

6. A lifting equipment weight limit device according to claim 1, characterized in that: The guide frame (1-3) guides the weight (2-1) to fall, the bottom diameter of the weight (2-1) is larger than the diameter of the middle hole (1-2-1) of the limit bracket (1-2), and the weight (2-1) is supported by the limit bracket (1-2) after falling, thereby preventing the limit switch (1-1) from being directly crushed.

7. A lifting equipment weight limiter according to claim 1, characterized in that: The traction steel wire (2-2) is easily broken due to stress concentration at both ends. If it breaks, since the diameter of the limit plate (2-3) is larger than the diameter of the middle through hole of the upper flange (4-5), the push rod (2-4) will be stuck by the upper flange (4-5) and will not fall and cause casualties.

8. The heavy hammer limit device for a sling according to claim 1, characterized in that: The parts of the weight mechanism (2), the guide mechanism (4) and the anti-sway mechanism (5) below the platform (3) can be all lifted out of the holes of the platform (3) by unscrewing the bolts on the mounting plate (4-3), so as to facilitate maintenance.

9. The heavy hammer limit device for a sling according to claim 1, characterized in that: The working principle of the sling weight limit device is that when the sling (7) rises and touches and lifts the weight mechanism (2), the weight (2-1) of the weight mechanism (2) falls, and the limit switch (1-1) of the trigger mechanism (1) is triggered, which can disconnect the lifting power of the sling (7), and the sling (7) immediately stops rising; at the same time, the sling (7) rises and approaches the height detector (6), and the height detector (6) receives a signal. When the height value of the sling reaches the warning value, the limit switch (1-1) can also be triggered to disconnect the lifting power of the sling (7), and the double protection measures prevent the sling (7) from hitting the top platform (3).

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