A cantilever fixing structure for a crane

Abstract

This utility model discloses a cantilever fixing structure for a crane, belonging to the field of crane technology. It includes a crane body and a cantilever. A connecting plate is welded to one end of the cantilever, and the connecting plate is fixedly connected to the crane body by multiple bolts. A fiber optic grating sensor monitors the welding fusion line in real time, realizing the early identification of weld fatigue cracks. By capturing strain change signals and coordinating with the linkage response of the controller and alarm, it can provide timely warnings before the cracks expand to a dangerous level, changing the lag and limitations of traditional manual inspection. The lateral movement component realizes the lateral fine adjustment of the wire take-up and unwinding component through a transmission structure such as a motor and a threaded rod. The horizontal alignment of the hook can be completed without moving the crane body, making the operation convenient.

Description

Technical Field

[0001] This utility model relates to the field of crane technology, and in particular to a cantilever fixing structure for a crane. Background Technology

[0002] In the structural composition of a crane, the cantilever, as the core component for lifting and transferring heavy objects, directly determines the operational safety and service life of the equipment through the stability of its connection with the main structure. Currently, for fixed-length cantilever sections (such as the standard section cantilever of a tower crane and the fixed boom of a port gantry crane), the industry widely adopts a rigid connection method using connecting plates (flanges) and high-strength bolts: the base of the cantilever is fixed to the flange through welding, and then high-strength bolts evenly distributed along the circumference of the flange are used to fasten it to the corresponding connecting plate of the crane's main structure, forming an integrated load-bearing system. This connection method, with its simple structure, high rigidity, and high load-bearing capacity, is widely used in various heavy-duty working conditions.

[0003] However, under long-term alternating loads and complex operating conditions, the structural weaknesses gradually became apparent. The weld fusion line between the cantilever root and the flange is a typical stress concentration area: during hoisting operations, the vertical load, horizontal bending moment, and torque borne by the cantilever are transmitted to the main structure through the weld, resulting in periodic alternating stress at the fusion line. With accumulated use, micro-cracks may develop inside the weld and gradually expand under continuous load. If not detected in time, this can lead to decreased connection rigidity, increased equipment vibration, or even serious safety accidents such as weld fracture and cantilever detachment. Traditional manual inspection methods rely on periodic shutdowns for testing, which is not only inefficient but also fails to capture subtle changes in the early stages of crack initiation, posing serious safety hazards.

[0004] Meanwhile, in actual crane operations, the lateral positioning accuracy of the cantilever is equally crucial to lifting efficiency and safety. For example, when there is a lateral deviation between the lifting target and the initial position of the cantilever, precise alignment must be achieved by adjusting the lateral position of the cantilever. Existing adjustment methods mostly rely on the overall movement of the main structure (such as the crawler movement of a crawler crane) or additional auxiliary lifting equipment, which are cumbersome to operate. Utility Model Content

[0005] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a cantilever fixing structure for cranes.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: it includes a crane body and a cantilever, one end of which is welded with a connecting plate, the connecting plate being fixedly connected to the crane body by multiple bolts, a fiber optic grating sensor being attached to the fusion line where the cantilever and the connecting plate are welded, an alarm and a controller being fixed to one side of the crane body by bolts, a lateral movement assembly being connected to the cantilever, and a cable rewinding assembly being connected to the lateral movement assembly.

[0007] As a further description of the above technical solution:

[0008] The fiber optic grating sensor, alarm, and controller are electrically connected.

[0009] As a further description of the above technical solution:

[0010] The lateral movement assembly includes an adjustment cavity formed in the cantilever. A second motor is fixed to one inner surface of the adjustment cavity by bolts. A threaded rod is welded to the output end of the second motor. The end of the threaded rod away from the second motor is rotatably connected to one inner surface of the adjustment cavity. A threaded block is threadedly connected to the outside of the threaded rod. A connecting block is welded to one side of the threaded block. One end of the connecting block extends through the outside of the cantilever and is connected to the take-up and unwinding assembly.

[0011] As a further description of the above technical solution:

[0012] The bottom wall of the cantilever has an elongated through hole, and the connecting block is slidably connected in the elongated through hole.

[0013] As a further description of the above technical solution:

[0014] The take-up and unwinding assembly includes a U-shaped plate. A motor is fixed to one outer surface of the U-shaped plate by bolts. The output end of the motor passes through one side of the U-shaped plate and is welded to a winding roller. A rope is wound around the outside of the winding roller, and a hook is fixed to one end of the rope.

[0015] As a further description of the above technical solution:

[0016] The end of the winding roller away from the motor is rotatably connected to the inner surface of the U-shaped plate.

[0017] As a further description of the above technical solution:

[0018] A limiting block is welded to one side of the threaded block, and a limiting groove is formed on the inner top surface of the adjusting cavity. The limiting block is slidably connected in the limiting groove.

[0019] This utility model has the following beneficial effects:

[0020] 1. In this utility model, the fiber optic grating sensor monitors the welding fusion line in real time, realizing the early identification of weld fatigue cracks. By capturing the strain change signal and coordinating with the controller and alarm, it can provide timely warnings before the cracks expand to a dangerous level, thus changing the lag and limitations of traditional manual inspection.

[0021] 2. In this utility model, the lateral movement component realizes the lateral fine adjustment of the wire take-up and unwinding component through the transmission structure such as the motor and the threaded rod. The horizontal alignment of the hook can be completed without moving the main body of the crane, which is convenient to operate. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of a cantilever fixing structure for a crane proposed in this utility model. Figure 1 ;

[0023] Figure 2 This is a schematic diagram of the overall structure of a cantilever fixing structure for a crane proposed in this utility model. Figure 2 ;

[0024] Figure 3 This is a schematic diagram of the overall structure of a cantilever fixing structure for a crane proposed in this utility model. Figure 3 ;

[0025] Figure 4 This is a cross-sectional schematic diagram of the cantilever of a crane cantilever fixing structure proposed in this utility model.

[0026] Figure 5 This is a schematic diagram of the cantilever of a crane cantilever fixing structure proposed in this utility model.

[0027] Legend:

[0028] 1. Crane body; 2. Controller; 3. Alarm; 4. Connecting plate; 5. Fiber optic grating sensor; 6. Cantilever; 7. U-shaped plate; 8. Winding roller; 9. Rope; 10. Motor 1; 11. Hook; 12. Long through hole; 13. Connecting block; 14. Adjusting cavity; 15. Motor 2; 16. Threaded rod; 17. Threaded block. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] Reference Figures 1-4An embodiment of this utility model includes a crane body 1 and a cantilever 6. A connecting plate 4 is welded to one end of the cantilever 6. The connecting plate 4 is fixedly connected to the crane body 1 by multiple bolts. A fiber optic grating sensor 5 is attached to the fusion line where the cantilever 6 and the connecting plate 4 are welded. An alarm 3 and a controller 2 are fixed to one side of the crane body 1 by bolts. A lateral movement component is connected to the cantilever 6, and a wire take-up and release component is connected to the lateral movement component.

[0031] The fiber optic grating sensor 5, alarm 3, motor 10, motor 2 15 are electrically connected to the controller 2. The lateral movement assembly includes an adjustment cavity 14 formed in the cantilever 6. Motor 2 15 is bolted to the inner surface of one side of the adjustment cavity 14. A threaded rod 16 is welded to the output end of motor 2 15. The end of the threaded rod 16 away from motor 2 15 is rotatably connected to the inner surface of one side of the adjustment cavity 14. A threaded block 17 is threadedly connected to the outside of the threaded rod 16. A connecting block 13 is welded to one side of the threaded block 17. One end of the connecting block 13 extends through the outside of the cantilever 6 and is connected to the cable take-up and unwinding assembly. An elongated through hole 12 is formed in the bottom wall of the cantilever 6. The connecting block 13 is slidably connected in the elongated through hole 12. 2 provides a sliding channel for the connecting block 13 and restricts its movement direction to ensure stability during lateral adjustment. The winding and unwinding assembly includes a U-shaped plate 7. The top surface of the U-shaped plate 7 is welded to the connecting block 13. A motor 10 is fixed to one side of the outer surface of the U-shaped plate 7 by bolts. The output end of the motor 10 passes through one side of the U-shaped plate 7 and is welded to a winding roller 8. A rope 9 is wound around the outside of the winding roller 8. A hook 11 is fixed to one end of the rope 9. The end of the winding roller 8 away from the motor 10 is rotatably connected to the inner surface of the U-shaped plate 7. A limit block is welded to one side of the threaded block 17. A limit groove is opened on the inner top surface of the adjusting cavity 14. The limit block is slidably connected in the limit groove to further restrict the movement trajectory of the threaded block 17.

[0032] Working principle: The cantilever 6 is rigidly connected to the crane body 1 via a connecting plate 4 welded to its end. Multiple bolts pass through the connecting plate 4 for fastening, forming a stable force transmission path and ensuring structural stability under heavy load conditions. The weld fusion line, as a key node for force transmission, directly affects the overall safety due to its stress state.

[0033] The fiber optic grating sensor 5 is attached to the welding fusion line between the cantilever 6 and the connecting plate 4 to sense the strain changes in this area in real time. When the weld develops micro-cracks due to fatigue and they propagate, the local strain will change abruptly. The fiber optic grating sensor 5 converts the strain signal into an optical signal change and transmits it to the controller 2. The controller 2 analyzes the signal. If the detected strain value exceeds the preset threshold (corresponding to the risk of crack propagation), the alarm 3 is immediately triggered to issue an audible and visual alarm, reminding the operator to stop the machine for inspection and avoid accidents.

[0034] The start motor 15 drives the threaded rod 16 to rotate. The threaded block 17 moves axially under the action of the threaded rod 16. At the same time, the sliding fit between the connecting block 13 and the elongated through hole 12, as well as the guiding and limiting of the limiting block and the limiting groove, ensures the stable movement of the threaded block 17. The connecting block 13 drives the wire take-up and release assembly to move laterally in sync, thereby adjusting the horizontal position of the hook 11 and achieving alignment with the hoisting target. This replaces the cumbersome operation of moving the traditional main structure, reducing energy consumption while improving adjustment efficiency.

[0035] The drive motor 10 drives the winding roller 8 to rotate forward or backward, thereby releasing or retracting the rope 9. When the winding roller 8 releases the rope 9, the hook 11 lowers and hooks the weight; conversely, the winding roller 8 retracts the rope 9, lifting the weight to complete the hoisting action. The U-shaped plate 7 provides stable support for the winding roller 8, ensuring that the rope 9 is evenly stressed during release and retraction, and preventing swaying.

[0036] All electrical components mentioned in this article are connected to an external main controller and 220V AC mains power. The main controller can be a conventional known device such as a computer for control. The detailed description of known functions and components is omitted in the specific implementation of this disclosure. In order to ensure the compatibility of the device, the operating methods used are consistent with the parameters of commercially available instruments.

[0037] In this utility model, unless otherwise explicitly specified and limited, the terms "installation", "setting", "connection", "fixing", "screw connection", etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0038] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A cantilever fixing structure for a crane, comprising a crane body (1) and a cantilever (6), characterized in that: A connecting plate (4) is welded to one end of the cantilever (6). The connecting plate (4) is fixedly connected to the crane body (1) by multiple bolts. A fiber optic grating sensor (5) is attached to the fusion line where the cantilever (6) and the connecting plate (4) are welded. An alarm (3) and a controller (2) are fixed to one side of the crane body (1) by bolts. A lateral movement assembly is connected to the cantilever (6), and a wire take-up and release assembly is connected to the lateral movement assembly.

2. A jib fixing structure for a crane according to claim 1, characterised in that: The fiber optic grating sensor (5), the alarm (3), and the controller (2) are electrically connected.

3. A jib fixing structure for a crane according to claim 1, characterized in that: The lateral movement assembly includes an adjustment cavity (14) formed in the cantilever (6). A second motor (15) is fixed to one inner surface of the adjustment cavity (14) by bolts. A threaded rod (16) is welded to the output end of the second motor (15). The end of the threaded rod (16) away from the second motor (15) is rotatably connected to one inner surface of the adjustment cavity (14). A threaded block (17) is threadedly connected to the outside of the threaded rod (16). A connecting block (13) is welded to one side of the threaded block (17). One end of the connecting block (13) extends through the cantilever (6) and is connected to the take-up and unwinding assembly.

4. A jib fixing structure for a crane according to claim 3, characterised in that: The bottom wall of the cantilever (6) is provided with an elongated through hole (12), and the connecting block (13) is slidably connected in the elongated through hole (12).

5. A jib fixing structure for a crane according to claim 1, characterized in that: The take-up and unwinding assembly includes a U-shaped plate (7), and a motor (10) is fixed to one side of the outer surface of the U-shaped plate (7) by bolts. The output end of the motor (10) passes through one side of the U-shaped plate (7) and is welded to a winding roller (8). A rope (9) is wound around the outside of the winding roller (8), and a hook (11) is fixed to one end of the rope (9).

6. A jib fixing structure for a crane according to claim 5, characterised in that: The end of the winding roller (8) away from the motor (10) is rotatably connected to the inner surface of the U-shaped plate (7).

7. A jib fixing structure for a crane according to claim 3, wherein: A limiting block is welded to one side of the threaded block (17), and a limiting groove is opened on the inner top surface of the adjusting cavity (14). The limiting block is slidably connected in the limiting groove.

Images