A heavy hammer position limiting device with self-cleaning function and a warning control method thereof

Abstract

The application discloses a heavy hammer limiting device with self-cleaning function, which comprises a heavy hammer sleeved outside a steel wire rope, a traction rope connected to the heavy hammer, an inner sleeve arranged on an inner ring of the heavy hammer and sleeved outside the steel wire rope, the inner sleeve adopting a sectional structure, a plurality of oil stain cleaning mechanisms arranged on the side wall of the inner sleeve, and a pressure sensing unit arranged in the inner sleeve. The application also discloses a warning control method based on the heavy hammer limiting device with self-cleaning function. The application solves the problem that the existing heavy hammer limiting device is in contact with lubricating oil on the outer surface of the steel wire rope, thereby causing internal oil stains, and prevents the existing heavy hammer limiting device from being triggered by mistake.

Description

Technical Field

[0001] This invention relates to counterweight limiting technology on lifting equipment, and more specifically, to a counterweight limiting device with self-cleaning function and its warning control method. Background Technology

[0002] If a hoisting accident occurs, it can involve damage to multiple people or equipment. Therefore, it is essential to select an appropriate safety level for the hoisting mechanism based on its usage.

[0003] The common forms and basic principles of lifting height limit switches are based on the fact that a motion action from the lifting transmission system triggers an electrical switch, thereby stopping the lifting transmission system and preventing over-winding accidents. These are generally divided into common and non-common limit switches. Common limit switches are constructed based on electrical or partially mechanical principles, limiting the lifting height through height sensors, screws, etc., and have both deceleration and stop control modes. By detecting when the hoisting mechanism reaches the critical lifting height (highest or lowest), the lifting action can be forcibly stopped, generally without cutting off the power supply. The other type is the non-common limit switch, usually referring to the counterweight limit switch. Through a straightforward mechanical principle combined with its electrical linkage, it effectively prevents over-winding accidents caused by the hoisting rising too high. It is a particularly important part of the limiting mechanism; once triggered, it cuts off the power to the entire crane, and personnel must manually reset the eccentric counterweight before power can be restored.

[0004] Currently, most counterweight limiters have been improved to eliminate the originally cumbersome and easily damaged hinge shaft and vertical rod. An open-type counterweight is installed directly next to the fixed pulley. After the counterweight is fitted onto the closed wire rope, a thin rope (wire rope) is threaded through it for suspension. A support ring is directly installed on the cover of the moving pulley of the hook. As the moving pulley rises, the support ring touches the counterweight, causing the eccentric end of the counterweight to fall, driving the small shaft of the switch to rotate. The moving contact separates from the stationary contact, breaking the circuit and preventing the lifting mechanism from moving in the lifting direction, thus providing a limit protection function. However, defects still exist in actual operation, and there is a possibility of error. The biggest problem is that oil stains on the surface of the wire rope can adhere to the inside of the counterweight, causing a pulling phenomenon and leading to malfunction of the counterweight. Another problem is the breakage of the counterweight traction rope (wire rope). This problem can be solved by changing the thin rope to a wire rope or by thickening it.

[0005] Another type of screw-type lifting height limiter uses a drum shaft to drive a screw. When it reaches the limit position, it triggers the limit switch, disconnecting the circuit to prevent the crane from overwinding (overlapping of wire ropes, wire ropes extending outside the drum). Common limit switches serve as the first line of defense in the hoist safety mechanism. Counterweight limit switches are typically used less frequently and are the second line of defense in the hoist safety mechanism.

[0006] Wire rope is one of the most critical components of any lifting machinery, and its safety and reliability are essential for smooth operation. Regular lubrication (grease) is required to ensure the wire rope's extensibility, reduce friction, and extend its service life. When the wire rope is excessively contaminated with oil, the inner wall of the counterweight limit switch frequently rubs against the greased wire rope, leading to frequent accidental triggering due to oil buildup. The hazards of these accidental triggers are twofold: First, they impact the electrical control circuit and mechanical mechanisms. Because the power circuit is forcibly disconnected instantaneously, the impact on both the electrical and mechanical structures is enormous. Second, once the counterweight limit switch is activated, manual reset is required. Personnel must climb onto the trolley, lift the eccentric counterweight, and activate the reset switch to restore power. This cumbersome and dangerous reset procedure, along with the disruption to production, cannot be effectively addressed. Furthermore, excessive oil accumulation on the inner wall of the counterweight limit switch frequently leads to accidental triggering. Currently, cleaning is done manually, which is time-consuming, labor-intensive, and carries the risk of working at height. Summary of the Invention

[0007] To address the aforementioned deficiencies in the existing technology, the purpose of this invention is to provide a self-cleaning counterweight limit device and its warning control method, thereby solving the problem of internal oil accumulation caused by contact with the lubricating oil on the surface of the wire rope in existing counterweight limit devices, and preventing the false triggering of existing counterweight limit devices.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] On the one hand, a self-cleaning hammer limiting device includes a hammer that is fitted around the outside of a wire rope, the hammer being connected to a traction rope, and an inner sleeve disposed on the inner ring of the hammer, the inner sleeve being fitted around the outside of the wire rope.

[0010] The inner sleeve adopts a segmented structure;

[0011] The inner sleeve is provided with multiple oil stain cleaning mechanisms on its side wall;

[0012] The inner sleeve is equipped with a pressure sensing unit.

[0013] Preferably, the inner sleeve is divided into three sections, including a first sleeve section, a second sleeve section, and a third sleeve section connected sequentially from bottom to top;

[0014] The first sleeve is attached to the inner ring of the weight by a magnetic attraction device.

[0015] Preferably, the first sleeve segment, the second sleeve segment, and the third sleeve segment are distinguished by different colors.

[0016] Preferably, each of the aforementioned oil stain cleaning mechanisms includes a ball bearing, an elastic scraper, a sludge discharge channel, a sludge scraper, and a scraper blade;

[0017] The ball bearings are mounted on the side wall of the inner sleeve via a support roller, and the inner surface of the ball bearings is in contact with the surface of the wire rope.

[0018] The elastic scraper contacts the outer surface of the ball;

[0019] One end of the mud discharge channel corresponds to the outer side of the ball bearing, and the other end passes through the outer side of the inner sleeve.

[0020] The scraper blade guides the oil on the surface of the ball bearings into the sludge discharge channel;

[0021] The scraper blades are multiple in number and are all located on the outer side of the inner sleeve, respectively at the connection positions of the first sleeve, the second sleeve, and the third sleeve.

[0022] Preferably, the pressure sensing unit includes:

[0023] The stopper has multiple components, which are distributed at the upper and lower ends of the first sleeve, the second sleeve and the third sleeve;

[0024] A limiter is located at the upper end of the third sleeve.

[0025] A spring pressure sensor is provided on the limiter;

[0026] The terminal device is connected to the limiter via a signal transmission line;

[0027] The rolling structure has three parts, which are respectively placed in the first section sleeve, the second section sleeve and the third section sleeve, and move along the roller tracks opened on the inner walls of the first section sleeve, the second section sleeve and the third section sleeve.

[0028] Preferably, the rolling structure is a roller or a ball;

[0029] If the rolling structure is a roller, then the roller conveyor is configured as a straight line.

[0030] If the rolling structure is a ball, then the roller conveyor is set to a spiral type.

[0031] Preferably, the rollers or the balls are moved along the roller track by guide rollers.

[0032] On the other hand, a warning control method based on a self-cleaning counterweight limit device includes the following steps:

[0033] S1. The operation of the winch drives the steel wire rope to move;

[0034] S2. The outer surface of the wire rope is in contact with the oil stain cleaning mechanism of the counterweight limiting device;

[0035] S3. During the contact motion of the ball bearings in the oil stain cleaning mechanism, the steel wire rope is driven to rotate, and the oil stains on the surface of the steel wire rope are stuck together.

[0036] S4. The elastic scraper removes oil stains from the surface of the ball;

[0037] S5. The removed oil sludge is gradually discharged through the sludge discharge channel after it has accumulated.

[0038] S6. The scraper removes the oil sludge discharged from the sludge discharge channel;

[0039] S7. Determine whether the oil stains in the counterweight limiting device are overloaded. If not, continue to determine. If yes, proceed to step S8.

[0040] S8. The rolling structure inside the first sleeve moves upward and touches the stopper at the upper end of the first sleeve, automatically rising to the second stage;

[0041] S9. The rolling structure inside the second sleeve moves upward and touches the stopper at the upper end of the second sleeve, automatically rising to the third section;

[0042] S10. Determine if the rolling structure inside the third sleeve moves upward and touches the spring pressure sensor. If not, continue to determine; if yes, proceed to step S11.

[0043] S11. The limiter sends a signal and transmits the signal to the terminal device through the signal transmission line;

[0044] S12. The terminal device issues an alarm and cuts off the control power supply of the winch.

[0045] This invention provides a self-cleaning counterweight limiter and its warning control method. It is an integrated device that combines adhesion level warning, automatic control protection, and automatic cleaning, based on the limiting control of the hoisting mechanism's operation in large mechanical equipment. Since counterweight limiters are mostly used in crane hoisting systems, the corresponding environment and the specific hoisting limiter used vary. Based on the basic principle of the hoisting height limiter, a motion is deflected from the hoisting transmission system to trigger the electrical switch, thereby stopping the hoisting transmission system and preventing over-winding accidents. In cases of excessive oil contamination on the wire rope, the counterweight limiter may be falsely triggered due to oil adhesion, impacting the electrical control circuit and forcibly disconnecting. Furthermore, the cumbersome and delayed manual reset cannot be effectively resolved. This invention is specifically designed to address the problem of abnormal counterweight movement caused by oil adhesion to the wire rope surface during hoisting operations in large lifting equipment. In actual production, it can effectively solve the problem of production logistics rhythm being affected by abnormal movement of the counterweight during crane lifting, and prevent impact damage to electrical components and mechanical structures caused by malfunction of the counterweight limit switch. This improves the crane's safe operation rate and achieves the goal of ensuring production safety and personnel safety. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structure of the counterweight limiting device of the present invention, which adopts a straight-line roller form;

[0047] Figure 2 This is a schematic diagram of the structure of the hammer limiting device of the present invention, which adopts a spiral rolling ball form;

[0048] Figure 3 This is a schematic diagram of the inner side of the inner sleeve in the counterweight limiting device of the present invention, wherein (a) is a schematic diagram of the roller conveyor being arranged in a straight line, and (b) is a schematic diagram of the roller conveyor being arranged in a spiral line.

[0049] Figure 4 This is a flowchart illustrating the warning control method of the hammer limit device of the present invention. Detailed Implementation

[0050] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0051] Combination Figure 1 and Figure 2As shown, the present invention provides a self-cleaning counterweight limiting device, including a counterweight 2 sleeved on the outside of a wire rope 1. A traction rope 4 is connected to the counterweight 2 via a hook 3. The height of the counterweight 2 is determined by the hook 3 and the traction rope 4. The wire rope 1 moves up and down with the operation of the winch, while the counterweight 2 is in a fixed position. The counterweight 2 will only move after the support ring at the top of the movable pulley lifts it up.

[0052] Structural configuration: A hook 3 is installed on the counterweight 2, and the height is positioned by the traction rope 4. The wire rope 1 is driven by a motor and a reducer to the drum. Through the rotation of the drum and the change of direction of the fixed pulley, the wire rope 1 is then transmitted to the gantry (lifting device), forming an upward and downward process. Therefore, the wire rope 1 moves dynamically up and down within the counterweight 2.

[0053] The counterweight limiting device of the present invention also includes an inner sleeve disposed on the inner ring of the counterweight 2, and the inner sleeve is sleeved on the outer side of the wire rope 1.

[0054] The internal sleeve adopts a segmented structure, including the first sleeve 5, the second sleeve 6, and the third sleeve 7 connected sequentially from bottom to top.

[0055] The first sleeve 5 is fixed to the inner ring of the weight 2 by the magnetic attraction device 8.

[0056] The inner sleeve has multiple oil stain cleaning mechanisms on its side wall. Each oil stain cleaning mechanism includes a ball bearing 9, an elastic scraper 10, a mud discharge channel 11, a mud scraper 21, and a scraper blade 12.

[0057] The ball bearing 9 is mounted on the side wall of the inner sleeve via the support roller 13, and rotates around the support roller 13. The inner side of the ball bearing 9 contacts the surface of the wire rope 1, thereby removing oil stains from the surface of the wire rope 1 by rotation.

[0058] The elastic scraper 10 contacts the outer surface of the ball 9 to remove the oil residue stuck to the ball 9.

[0059] One end of the mud discharge channel 11 corresponds to the outer side of the ball bearing 9, and the other end passes through the outer side of the inner sleeve.

[0060] The scraper 21 has multiple blades, all located on the outer side of the inner sleeve, respectively at the connection position between the first sleeve 5, the second sleeve 6, and the third sleeve 7.

[0061] After the lubricating grease on the surface of the wire rope 1 enters the inner sleeve, it generates a rolling effect through the rolling body of the ball bearings 9, causing the grease to extend outward in multiple directions. After the elastic scraper 10 contacts the oil stains on the surface of the ball bearings 9, it peels the oil stains off the surface of the ball bearings 9. The remaining oil stains come into contact with the scraper 21 and are discharged through the open mud discharge channel 11, playing a self-cleaning role, thereby achieving the effect of automatically cleaning the inner wall. The inner sleeve is divided into three sections with the diameter decreasing from large to small (the first section sleeve 5 has the largest diameter, and the third section sleeve 7 has the smallest diameter). A scraper 21 is installed between each section. When the inner sleeve floats up and down connected by the ball bearings 9, the scraper 21 will clean the oil stains overflowing from the mud discharge channel 11, so that the discharged oil sludge will automatically disengage from the counterweight limiting device of the present invention. The present invention provides a counterweight limiting device to solve the problem of malfunction caused by the counterweight rising with the wire rope due to grease adhesion. Therefore, the device only has upward cleaning and limiting control functions, and does not have downward design and installation based on the principle of the weight of the wire rope and the counterweight.

[0062] The first sleeve 5, the second sleeve 6, and the third sleeve 7 are distinguished by different colors, displaying red, yellow, and blue warnings. The inner sleeves overlap after being nested with the counterweight for limiting movement. The upward and downward movement only occurs after the inner wall balls 9, the rolling structure, and the wire rope 1 come into contact and adhere. This movement relies on the balls 9 and the rolling structure as moving parts. An inner roller track 17 is used. The greater the adhesion, the greater the floating effect. The rolling structure can take many forms, such as... Figure 3 The diagram shows two different forms of conduction, one of which is as follows: Figure 3 As shown in (a), a pattern with the rolling elements (rollers 18) arranged in a straight line is used; another pattern is as follows: Figure 3 As shown in (b), a spiral pattern with 19 rolling balls (spheres) is adopted, achieving essentially the same effect. The degree of vertical floating effect of the internal sleeve, from low to high, can be displayed in different colors, making it easy for operators to intuitively understand the degree of adhesion of the wire rope, thus facilitating the determination of maintenance time.

[0063] The inner sleeve is equipped with a pressure sensing unit, which includes:

[0064] The stopper 13 has multiple components, which are distributed at the upper and lower ends of the first sleeve 5, the second sleeve 6 and the third sleeve 7.

[0065] The limiter 14 is located at the upper end of the third sleeve 7.

[0066] A spring pressure sensor 15 is mounted on the limiter 14.

[0067] The terminal device is connected to the limit switch 14 via the signal transmission line 16.

[0068] The rolling structure has three sections, which are respectively placed in the first section sleeve 5, the second section sleeve 6, and the third section sleeve 7, and move along the roller conveyor 17 opened on the inner wall of the first section sleeve 5, the second section sleeve 6, and the third section sleeve 7.

[0069] The rolling structure is either roller 18 or ball 19.

[0070] If the rolling structure is roller 18, then the roller conveyor 17 is correspondingly set as a straight-line type, such as... Figure 1 and Figure 3 As shown in (a).

[0071] If the rolling structure is a ball 19, then the roller conveyor 17 is correspondingly set to a spiral type, such as... Figure 2 and Figure 3 As shown in (b).

[0072] Both roller 18 and ball 19 move along roller table 17 via guide roller 20.

[0073] Due to inherent structural flaws in the original design of the counterweight 2, a malfunction would directly disconnect the main power supply, preventing the control circuit from receiving power. Power could only be restored manually by resetting the switch connected to the eccentric counterweight, which was inconvenient. Therefore, a spring pressure sensor 15 is installed at the upper end of the third sleeve 7. When the roller 18 or ball 19 moves and touches the end spring, the spring pressure sensor 15 is triggered. The limit switch 14 transmits the signal to the terminal equipment via the signal transmission line 16 in the middle of the wire rope 1. Upon receiving the signal, the terminal equipment automatically disconnects the hoisting control circuit in the operation control circuit and triggers an audible alarm in the control room. Since the counterweight limit switch does not activate at this time, the main power supply circuit is not disconnected, thus not affecting the normal operation of other mechanisms. This also facilitates inspection, operation, and reset.

[0074] Combination Figure 4 As shown, the present invention also provides a warning control method based on the self-cleaning counterweight limit device of the present invention, comprising the following steps:

[0075] S1. The operation of the winch drives the wire rope 1 to move;

[0076] S2, The outer surface of the wire rope 1 comes into contact with the oil stain cleaning mechanism of the counterweight limit device;

[0077] S3, the ball bearing 9 is driven to rotate, and the oil stains on the surface of the wire rope 1 are stuck together;

[0078] S4. The elastic scraper 10 removes oil stains from the surface of the ball bearing 9;

[0079] S5. The removed oil sludge is discharged through the sludge discharge channel 11;

[0080] S6. Scraper 12 removes the oil and grease discharged from sludge discharge channel 11;

[0081] S7. Determine whether the oil stains in the counterweight limit device are overloaded. If not, continue to determine. If yes, proceed to step S8.

[0082] S8. The rolling structure inside the first sleeve 5 moves upward and touches the stopper 13 at the upper end of the first sleeve 5, and automatically rises to the second stage;

[0083] S9. The rolling structure inside the second sleeve 6 moves upward and touches the stopper 13 at the upper end of the second sleeve 6, automatically rising to the third section;

[0084] S10. Determine if the rolling structure inside the third sleeve 7 moves upward and touches the spring pressure sensor 15. If not, continue to determine; if yes, proceed to step S11.

[0085] S11, the limit switch 14 sends a signal and transmits the signal to the terminal device through the signal transmission line 16;

[0086] S12. An alarm is issued by the terminal equipment, and the power supply to the winch control is cut off.

[0087] The present invention's counterweight limiting device consists of an inner sleeve nested within the inner wall of the counterweight. The inner side of this inner sleeve contains hollow ball bearings 9, which are fixed by a support roller 13. Since the counterweight 2 is pulled by a thin steel wire rope 1 to maintain free movement, the steel wire rope 1 rubs against the ball bearings 9 as it passes through the inner sleeve, adhering oil to the ball bearings 9. Based on the movement of the ball bearings 9 under force, the adhered oil is carried to the outside of the inner sleeve, where it is removed by an external cleaning structure. Once a certain amount of oil is collected, it naturally falls off, thus removing the oil. If the oil viscosity is high or the amount is excessive, it rises to the second sleeve 6 for intensive cleaning, and then gradually ascends to the third sleeve 7. The internal structures of the three sleeves are similar, and each is composed of three different colors for easy identification by the operator. A stopper 13 with a limiting function is installed at the top of the third sleeve 7. Finally, the limiter 14 uses a signal transmission function to provide a progressive protection mechanism. These include the common limit action, the anti-adhesion counterweight device control action, and the counterweight limit action. An additional layer of protection is added to this mechanism, effectively preventing erroneous operation of the (unusual) counterweight limit.

[0088] The internal sleeve and the counterweight 2 are assembled in a separate form, which makes cleaning and replacement more convenient. Only the device needs to be replaced, and the counterweight is completely maintenance-free.

[0089] This invention is specifically designed to address the problem of abnormal hammer movement caused by oil contamination adhering to the wire rope surface during hoisting operations in large lifting equipment. In actual production, it effectively solves the disruption to production logistics rhythm caused by abnormal hammer movement during crane hoisting, and prevents impact damage to electrical components and mechanical structures caused by malfunctioning hammer limit switches. This improves the safety rate of lifting operations, achieving the goal of ensuring production safety and personnel safety.

[0090] This invention effectively analyzes the abnormal state of the counterweight limit and constructs a novel split sleeve design, which is inserted into the inner wall of the counterweight. The self-cleaning effect greatly improves the safe operation performance of the crane. It has high application value for similar lifting operations. It can be promoted and used in major steel enterprises in China and has a very broad application prospect.

[0091] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A counterweight limiting device with a self-cleaning function, comprising a counterweight fitted around the outside of a wire rope, wherein a traction rope is connected to the counterweight, characterized in that: It also includes an inner sleeve disposed on the inner ring of the counterweight, the inner sleeve being fitted over the outer side of the wire rope; The inner sleeve adopts a segmented structure; The inner sleeve is provided with multiple oil stain cleaning mechanisms on its side wall; The inner sleeve is equipped with a pressure sensing unit. The inner sleeve is divided into three sections, including a first sleeve section, a second sleeve section, and a third sleeve section connected sequentially from bottom to top; The first sleeve is attached to the inner ring of the counterweight via a magnetic attraction device. The first sleeve segment, the second sleeve segment, and the third sleeve segment are distinguished by different colors. Each of the aforementioned oil stain cleaning mechanisms includes a ball bearing, an elastic scraper, a mud discharge channel, a mud scraper, and a scraper blade; The ball bearings are mounted on the side wall of the inner sleeve via a support roller, and the inner surface of the ball bearings is in contact with the surface of the wire rope. The elastic scraper contacts the outer surface of the ball; One end of the mud discharge channel corresponds to the outer side of the ball bearing, and the other end passes through the outer side of the inner sleeve. The scraper blade guides the oil on the surface of the ball bearings into the sludge discharge channel; The scraper blades are multiple in number and are all located on the outer side of the inner sleeve, respectively at the connection positions of the first sleeve, the second sleeve, and the third sleeve.

2. The self-cleaning counterweight limiting device according to claim 1, characterized in that, The pressure sensing unit includes: The stopper has multiple components, which are distributed at the upper and lower ends of the first sleeve, the second sleeve and the third sleeve; A limiter is located at the upper end of the third sleeve. A spring pressure sensor is provided on the limiter; The terminal device is connected to the limiter via a signal transmission line; The rolling structure has three parts, which are respectively placed in the first section sleeve, the second section sleeve and the third section sleeve, and move along the roller tracks opened on the inner walls of the first section sleeve, the second section sleeve and the third section sleeve.

3. The self-cleaning counterweight limiting device according to claim 2, characterized in that: The rolling structure is a roller or a ball; If the rolling structure is a roller, then the roller conveyor is configured as a straight line. If the rolling structure is a ball, then the roller conveyor is set to a spiral type.

4. The self-cleaning counterweight limiting device according to claim 3, characterized in that: Both the rollers and the balls move along the roller track via guide rollers.

5. A warning control method based on the self-cleaning counterweight limit device according to any one of claims 2-4, characterized in that, Includes the following steps: S1. The operation of the winch drives the steel wire rope to move; S2. The outer surface of the wire rope is in contact with the oil stain cleaning mechanism of the counterweight limiting device; S3. The ball bearings are driven to rotate and stick the oil stains on the surface of the wire rope; S4. The elastic scraper removes oil stains from the surface of the ball; S5. The removed oil sludge is discharged through the sludge discharge channel; S6. The scraper removes the oil sludge discharged from the sludge discharge channel; S7. Determine whether the oil stains in the counterweight limiting device are overloaded. If not, continue to determine. If yes, proceed to step S8. S8. The rolling structure inside the first sleeve moves upward and touches the stopper at the upper end of the first sleeve, automatically rising to the second section; S9. The rolling structure inside the second sleeve moves upward and touches the stopper at the upper end of the second sleeve, automatically rising to the third segment; S10. Determine if the rolling structure inside the third sleeve moves upward and touches the spring pressure sensor. If not, continue to determine; if yes, proceed to step S11. S11. The limiter sends a signal and transmits the signal to the terminal device through the signal transmission line; S12. The terminal device issues an alarm and cuts off the control power supply of the winch.

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