A bolt locking structure

Abstract

This utility model relates to the field of engineering machinery technology and provides a bolt locking structure, including a first workpiece plate and a second workpiece plate stacked together, a screw rod passing through the first workpiece plate and the second workpiece plate, a nut being provided at the top of the screw rod, a spacer being provided between the nut and the first workpiece plate, a threaded cylinder being provided below the second workpiece plate, and a welding block being provided between the side wall of the threaded cylinder and the lower side wall of the second workpiece plate, which greatly enhances the anti-loosening ability of the threaded pair and avoids thread loosening caused by vibration.

Description

Technical Field

[0001] This utility model relates to the field of engineering machinery technology, specifically to a bolt locking structure. Background Technology

[0002] Excavators are a type of earthmoving machinery in the field of construction machinery equipment, mainly used for excavating materials above or below the machine's bearing surface. Especially in the working scenarios of large excavators, the requirements for bolt tightening are becoming increasingly stringent. Currently, tightening technology mainly relies on pairs of bolts, washers, and nuts, with the nuts welded to the workpiece to be tightened.

[0003] For large excavators, the entire vehicle vibrates significantly. The vibration of an excavator is not unidirectional, but rather a complex multidimensional vibration existing in the front-to-back, left-to-right, up-down, and rotational directions. Traditional bolted connections may only have good resistance to loads in one direction, but cannot cope with this composite load that comes from all four directions. The bolts of the cover frame will loosen or even break in a very short time. Utility Model Content

[0004] To achieve the above objectives, this utility model proposes a bolt locking structure, including a first workpiece plate and a second workpiece plate stacked together, a screw rod passing through the first workpiece plate and the second workpiece plate, a nut being provided at the top of the screw rod, a spacer being provided between the nut and the first workpiece plate, a threaded cylinder being provided below the second workpiece plate, and the side wall of the threaded cylinder being fixedly connected to the lower side wall of the second workpiece plate.

[0005] A further configuration is that the spacer is fitted onto the outside of the screw, and the connection between the spacer and the screw can bear a greater preload, increase the friction of the nut plane, and further improve the anti-loosening performance.

[0006] Further configured, the weld block has a triangular cross-section, which provides a larger welding area and structural strength, enhancing the connection rigidity between the threaded cylinder and the second workpiece plate.

[0007] A further configuration is made such that the outer diameter of the spacer is larger than the diameter of the nut, thereby increasing the contact area between the spacer and the first workpiece plate.

[0008] A further configuration is provided in which a first through hole is provided inside the spacer, the first through hole being larger than the diameter of the screw, allowing the spacer to have a certain amount of micro-movement space on the screw, which facilitates alignment and adjustment during installation, while reducing stress concentration.

[0009] A further configuration is provided where a second through hole is formed through the center of the first workpiece plate. The diameter of the second through hole is larger than the diameter of the first through hole, thus providing greater allowance for movement of the spacer and the screw.

[0010] A further configuration is provided, in which a third through hole is formed through the center of the second workpiece plate, the diameter of the second through hole is greater than the diameter of the third through hole, and the diameter of the first through hole is equal to the diameter of the third through hole. By setting the second through hole to be larger than the third through hole and the first through hole to be equal to the third through hole, the precise alignment of the screw and the threaded cylinder is ensured.

[0011] A further configuration is that the surface area of ​​the first workpiece plate is greater than the surface area of ​​the spacer, and the surface area of ​​the first workpiece plate is greater than the surface area of ​​the spacer, thus providing a wider support surface.

[0012] A further configuration is made such that the surface area of ​​the second workpiece plate is greater than the surface area of ​​the sleeve, and the surface area of ​​the second workpiece plate is greater than the surface area of ​​the threaded cylinder, thereby enhancing the wrapping and support of the workpiece plate for the threaded cylinder.

[0013] Furthermore, the spacer, screw, and threaded cylinder are arranged coaxially. This coaxial arrangement ensures the uniformity and consistency of force transmission and avoids additional bending moments or shear forces caused by eccentricity.

[0014] The beneficial effects of one or more of the above technical solutions: This utility model proposes an anti-loosening structure with spacers and threaded cylinders at both ends of a threaded post. The spacers clamp the threaded cylinder through a first workpiece plate and a nut, increasing the friction between the first workpiece plate and the nut. The threaded cylinder is positioned below a second workpiece plate, with its sidewall welded to the lower sidewall of the second workpiece plate. The threaded cylinder and the second workpiece plate are welded together by a welding block, forming a dual locking effect of thread friction and clamping. Compared to traditional single nut locking, this significantly enhances the anti-loosening capability of the threaded pair, preventing thread loosening caused by vibration. The addition of spacers also increases the bolt preload. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute a limitation thereof.

[0016] Figure 1 This is a schematic diagram of the structure of this utility model.

[0017] In the figure, 1. First workpiece plate; 2. Second workpiece plate; 3. Screw; 4. Nut; 5. Spacer; 6. Threaded cylinder; 7. Welding block; 8. First through hole; 9. Second through hole; 10. Third through hole. Detailed Implementation

[0018] The specific implementation of this embodiment will now be described with reference to the accompanying drawings.

[0019] Example 1 A bolt locking structure, as shown in the reference Figure 1 The structure includes a first workpiece plate 1 and a second workpiece plate 2 stacked together. A screw 3 runs through both workpiece plates 1 and 2, with a nut 4 at the top of the screw 3. A spacer 5 is placed between the nut 4 and the first workpiece plate 1. A threaded cylinder 6 is placed below the second workpiece plate 2, and its sidewall is welded to the lower sidewall of the second workpiece plate 2, forming a welded block 7. This basic structure, through the synergistic effect of multiple components, constructs a multi-level, multi-path force transmission system, which can effectively cope with the complex multi-dimensional vibrations generated by equipment such as excavators during operation, fundamentally solving the technical problem of easy loosening under long-term vibration in traditional single-nut locking methods.

[0020] Spacer 5 is fitted onto the outside of screw 3, further enhancing its anti-loosening performance. This allows spacer 5 to better maintain preload in vibration environments, reducing the risk of loosening, while also facilitating installation and adjustment. This internal and external threaded structure is equivalent to adding a secondary locking unit below a traditional nut. When the main nut 4 shows a slight tendency to loosen under vibration, the threads of spacer 5 immediately generate additional frictional resistance to offset it, forming a dynamic anti-loosening compensation mechanism.

[0021] The weld block 7 has a triangular cross-section, which provides a larger welding area and structural strength, enhancing the connection rigidity between the threaded cylinder 6 and the second workpiece plate 2, effectively dispersing vibration stress, preventing fatigue cracking at the weld, and improving overall reliability. The stable geometry of the triangle allows it to distribute stress more evenly to the area of ​​the second workpiece plate 2 when subjected to alternating stress from different directions, avoiding stress concentration at the root of the weld point and greatly improving the fatigue life of the welded joint under harsh working conditions.

[0022] The outer diameter of the spacer 5 is larger than that of the nut 4, resulting in a larger contact area between the spacer 5 and the first workpiece plate 1. This allows for a more uniform pressure distribution, increases frictional resistance, and prevents the nut 4 from loosening under vibration. Simultaneously, this design helps improve the retention of preload. The larger contact area means lower surface pressure, which not only prevents the surface of the first workpiece plate 1 from being crushed, but more importantly, it forms a friction interface. The frictional force generated at this interface is greater than the thread loosening torque between the nut 4 and the spacer 5, thus achieving a mechanical self-locking effect.

[0023] The spacer 5 is provided with a first through hole 8, which is larger than the diameter of the screw 3. This allows the spacer 5 to have a certain amount of micro-movement space on the screw 3, which is convenient for alignment and adjustment during installation and reduces stress concentration. Combined with the threaded connection, this design can better adapt to the small displacement caused by vibration and maintain the locking effect. It allows the system to have a certain buffer margin when subjected to impact loads, avoiding the formation of rigid impacts, thereby protecting the thread teeth from being sheared off, and ensuring that the preload can be maintained stably for a long time.

[0024] A second through hole 9 is formed through the center of the first workpiece plate 1. The diameter of the second through hole 9 is larger than that of the first through hole 8, providing greater allowance for movement of the spacer 5 and the screw 3. This avoids interference caused by machining errors or installation deviations, ensuring that the spacer 5 can fully press the first workpiece plate 1, and optimizing the preload application process. This stepped hole design is key to achieving precise assembly and effective clamping. It ensures that all installation tolerances are accommodated within the second through hole 9, allowing the lower end face of the spacer 5 to achieve complete surface contact with the upper surface of the first workpiece plate 1, thereby applying a purely axial, non-eccentric preload.

[0025] A third through hole 10 is formed through the center of the second workpiece plate 2. The diameter of the second through hole 9 is larger than that of the third through hole 10, and the diameter of the first through hole 8 is equal to that of the third through hole 10. This ensures precise alignment between the screw 3 and the threaded cylinder 6, optimizing the force transmission path. This design reduces eccentric loads, improves the meshing efficiency of the threaded pair, and enhances the anti-loosening capability. This precise matching relationship of through hole dimensions constructs an ideal force flow path from the nut 4 to the threaded cylinder 6. The force line is transmitted straight along the axial direction of the screw 3, minimizing the bending moment caused by eccentricity. This ensures that the entire connection structure remains stable during vibration, and the threads of the threaded pair are subjected to uniform force, thus doubling the anti-loosening performance.

[0026] The surface area of ​​the first workpiece plate 1 is larger than that of the spacer 5, providing a wider support surface, dispersing the pressure applied by the nut 4 and the spacer 5, preventing local deformation or damage, and increasing the friction with the spacer 5, further improving the anti-loosening performance. The wide base plate design transforms the concentrated load of the locking point into a distributed load, like providing a stable "foundation" for the bolt connection. This not only protects the connected parts, but also significantly improves the ability to resist the rotation of the nut 4 by increasing the friction radius, making the locking structure more robust.

[0027] The surface area of ​​the second workpiece plate 2 is larger than that of the threaded cylinder 6, which enhances the wrapping and support of the threaded cylinder 6 by the second workpiece plate 2, effectively distributes the vibration load, reduces stress concentration in the threaded cylinder 6, and improves the durability and vibration resistance of the connection structure. The enlarged design of the lower workpiece plate is also crucial. It provides a stable mounting platform for the welding block 7 and the threaded cylinder 6, ensuring that the load from the threaded cylinder 6 can be smoothly diffused to the entire second workpiece plate 2, avoiding the generation of local high-stress areas, thereby ensuring the structural integrity of the entire connection under long-term high-intensity vibration.

[0028] The spacer 5, screw 3, and threaded cylinder 6 are coaxially arranged, ensuring the uniformity and consistency of force transmission and avoiding additional bending moments or shear forces caused by eccentricity. This maintains the stability and integrity of the bolted connection under multidimensional vibration environments, significantly reducing the risk of loosening. Coaxiality is a core technical requirement for high-performance bolted connections. This invention forcibly guarantees this through structural design, allowing the axial preload to be used most efficiently, entirely for generating friction to prevent loosening.

[0029] Although the specific embodiments of the present utility model have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present utility model. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solution of the present utility model are still within the scope of protection of the present utility model.

Claims

1. A bolt locking structure, characterized in that, The device includes a first workpiece plate and a second workpiece plate stacked together. A screw is provided through the first workpiece plate and the second workpiece plate. A nut is provided on the top of the screw. A spacer is provided between the nut and the first workpiece plate. A threaded cylinder is provided below the second workpiece plate. A welding block is provided between the side wall of the threaded cylinder and the lower side wall of the second workpiece plate.

2. The bolt locking structure according to claim 1, characterized in that, The spacer is fitted onto the outside of the screw, and the inside of the spacer is threaded. The spacer and the screw are connected by the thread.

3. The bolt locking structure according to claim 1, characterized in that, The welded block has a triangular cross-section.

4. The bolt locking structure according to claim 1, characterized in that, The outer diameter of the spacer is larger than the diameter of the nut.

5. A bolt locking structure according to claim 1, characterized in that, The spacer sleeve is provided with a first through hole, which is larger than the diameter of the screw.

6. A bolt locking structure according to claim 5, characterized in that, A second through hole is formed through the center of the first workpiece plate, and the diameter of the second through hole is larger than the diameter of the first through hole.

7. A bolt locking structure according to claim 6, characterized in that, A third through hole is formed through the center of the second workpiece plate. The diameter of the second through hole is larger than the diameter of the third through hole, and the diameter of the first through hole is equal to the diameter of the third through hole.

8. A bolt locking structure according to claim 1, characterized in that, The surface area of ​​the first workpiece plate is greater than the surface area of ​​the spacer.

9. A bolt locking structure according to claim 1, characterized in that, The surface area of ​​the second workpiece plate is greater than the surface area of ​​the sleeve.

10. A bolt locking structure according to claim 1, characterized in that, The spacer, screw, and threaded cylinder are arranged coaxially.

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