Double-thread anti-falling bolt for bridge

Abstract

The utility model relates to the technical field of fasteners, in particular to a double-thread anti-falling bolt for a bridge, which comprises a screw head, a screw rod, a large nut, a small nut and a bolt sleeve, the screw rod is fixed below the screw head and comprises a forward screw rod section and a reverse screw rod section, the forward screw rod section is arranged above the reverse screw rod section, and the large nut is arranged on the reverse screw rod section. The forward screw section penetrates through the connecting plate and is connected and fixed by a large nut, a small nut is arranged below the large nut, the small nut is connected and fixed to the reverse screw section, and bolt sleeves are arranged on the outer sides of the large nut and the small nut. According to the double-thread anti-falling bolt for the bridge, the double-thread design is adopted, the bolt is prevented from loosening under the vibration impact condition, and the stability of a bridge connecting structure is improved; and the bolt sleeve coated with the anti-seepage coating is arranged, and the sealing ring is adopted for protecting the nut joint, so that the joint is prevented from being corroded by the outside, the use safety of the nut is improved, the service life of the nut is prolonged, and the maintenance cost is reduced.

Description

[Technical field]

[0001] The utility model relates to the technical field of fasteners, and more specifically to a double-threaded anti-falling bolt for bridges. [Background technology]

[0002] Steel structure bridges are an important part of bridge engineering. A large number of bolt assemblies are required during the construction of steel structure bridges. The bolt assemblies mainly consist of two parts: the bolt body and the nut body, and may be flexibly equipped with appropriate washers and other components according to the needs of use.

[0003] However, bridges are generally exposed to harsh atmospheric corrosion conditions such as rivers, lakes and seas. The joint gaps of the node components of the bridge steel structure are generally prone to retaining corrosive media such as moisture and salt, and anti-corrosion spraying cannot be performed at these locations, causing rust problems on the threads inside the nuts of the bolts, which in turn causes stress corrosion of the bolts, leading to rapid breakage, increasing safety hazards. After the bolts break, in order to ensure the safety of the structure, the broken bolts need to be replaced, which results in a long construction period and high maintenance costs.

[0004] An existing anti-slip fastening bolt, with announcement number CN 220726823 U, comprises: a bolt, the bolt comprising a bolt head and a screw rod, the bolt being used to penetrate the fastener to be fastened; a nut, the nut and the bolt cooperate to fasten the fastener to be fastened; and an anti-slip rod, the anti-slip rod being installed at the tail of the bolt. This utility model provides an insertion slot, a receiving slot and a support hole at the tail of the screw rod, inserts the elastic rod body into the insertion slot, and inserts the anti-slip rod head into the support hole. During the tightening process of the nut, the elastic rod body will be bent by the nut and then received by the receiving slot, and the anti-slip rod head will be completely disassembled into the support hole. After the nut is rotated into place, the elastic rod body will return to its original shape, and the anti-slip rod head will slide out of the support hole to support the nut, thereby playing an anti-slip effect. This nut has good anti-slip ability, but because the connection is not treated, when this bolt is applied to the bridge connection node, moisture and salt will corrode the inside of the bolt, causing the bolt to break. [Contents of the utility model]

[0005] In order to overcome the above-mentioned defects of the prior art, the purpose of the utility model is to provide a double-threaded anti-falling bolt for bridges, which has good anti-falling ability and anti-penetration performance.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a double-threaded anti-falling bolt for bridges, comprising a screw head, a screw rod, a large nut, a small nut, and a bolt sleeve, wherein the screw rod is fixed below the screw head, the screw rod comprises a forward screw section and a reverse screw section, the forward screw section is arranged above the reverse screw section, the forward screw section passes through a connecting plate and is connected and fixed by a large nut, a small nut is arranged below the large nut, the small nut is connected and fixed to the reverse screw section, and bolt sleeves are arranged on the outside of the large nut and the small nut.

[0007] Preferably, the screw head is hexagonal, and a plurality of locking teeth are provided at the bottom of the screw head to increase the friction between the screw head and the connecting plate.

[0008] Preferably, the forward screw segment and the reverse screw segment have external threads in opposite directions, and the diameter of the forward screw segment is larger than the diameter of the reverse screw segment.

[0009] Preferably, a gasket is provided between the large nut and the connecting plate, and a connecting hole is provided at the center of each of the six outer sides of the nut.

[0010] Preferably, a plurality of washers are provided between the large nut and the small nut.

[0011] Preferably, the bolt sleeve comprises a bolt sleeve body, a plastic layer, a hollow cavity, a sealing ring, and a fixed plug. The inner side of the bolt sleeve body is provided with a plastic layer, the inner side of the plastic layer is a hollow cavity, the bottom of the bolt sleeve body is provided with a sealing ring, and the side of the bolt sleeve body is provided with a fixed plug.

[0012] Preferably, a layer of anti-seepage coating is applied on the outside of the bolt sleeve, and the sealing ring is made of rubber material.

[0013] Preferably, the fixing plug matches the connecting hole on the nut.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] 1. The utility model adopts a double-thread anti-falling bolt for bridges, which adopts a double-thread design, can prevent the bolts from loosening under vibration and impact conditions, and improve the stability of the bridge connection structure.

[0016] 2. The utility model discloses a double-threaded anti-falling bolt for bridges. The outside of the bolt sleeve is coated with an anti-seepage coating and a sealing ring is used to protect the nut connection, which effectively avoids external erosion of the connection, improves the safety of the nut, prolongs its service life, and reduces maintenance costs.

Brief Description of the Drawings

[0017] Figure 1 This is a schematic diagram of the structure of a double-threaded anti-falling bolt for bridges of the utility model;

[0018] Figure 2 This is a front view of a double-threaded anti-falling bolt for bridges of the utility model;

[0019] Figure 3 This is a schematic diagram of the structure of a double-threaded anti-falling bolt sleeve for a bridge according to the utility model;

[0020] In the figure: 1-screw head, 2-screw, 21-forward screw segment, 22-reverse screw segment, 3-large nut, 31-connecting hole, 4-small nut, 5-bolt sleeve, 51-bolt sleeve body, 52-plastic layer, 53-hollow cavity, 54-sealing ring, 55-fixed plug, 6-connecting plate. [Specific implementation method]

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] See also Figure 1 , 2 In the embodiment of the utility model, a double-threaded anti-falling bolt for a bridge includes a screw head 1, a screw rod 2, a large nut 3, a small nut 4, and a bolt sleeve 5. The screw head 1 is hexagonal, and a plurality of locking teeth are provided at the bottom of the screw head 1 to increase the friction between the screw head 1 and the connecting plate 6. The screw rod 2 is fixedly connected below the screw head 1. The screw rod 2 includes a forward screw rod segment 21 and a reverse screw rod segment 22. The forward screw rod segment 21 is arranged above the reverse screw rod segment 22. The forward screw rod segment 21 and the reverse screw rod segment 22 are oppositely arranged. The outer thread of the screw segment 21 in the forward direction is larger than the diameter of the reverse screw segment 22. The forward screw segment 21 passes through the connecting plate 6 and is connected and fixed by the large nut 3. A gasket is provided between the large nut 3 and the connecting plate 6. A connecting hole 31 is provided in the center of the six sides of the outer side of the nut 3. A small nut 4 is provided under the large nut 3. Several gaskets are provided between the large nut 3 and the small nut 4. The small nut 4 is connected and fixed to the reverse screw segment 22. Bolt sleeves 5 are provided on the outer sides of the large nut 3 and the small nut 4.

[0023] See also Figure 3In the embodiment of the utility model, a double-threaded anti-falling bolt for a bridge is provided. The bolt sleeve 5 includes a bolt sleeve body 51, a plastic layer 52, a hollow cavity 53, a sealing ring 54, and a fixed plug block 55. The bolt sleeve body 51 is coated with an anti-seepage coating on the outside, and a plastic layer 52 is provided on the inside of the bolt sleeve body 51. The inside of the plastic layer 52 is a hollow cavity 53. A sealing ring 54 is provided at the bottom of the bolt sleeve body 51, and the sealing ring 54 is made of rubber material. A fixed plug block 55 is provided on the side of the bolt sleeve body 51, and the fixed plug block 55 matches the connecting hole 31 on the nut 3.

[0024] Working principle:

[0025] When the double-threaded anti-falling bolt for bridges is used, the bottom of the screw rod 2 is passed through the connecting plate 6, and the bottom of the screw head 1 is placed above the connecting plate 6. Since a plurality of locking teeth are provided at the connection between the screw head 1 and the connecting plate 6, the shear resistance of the connecting surface is improved. After a gasket is placed on the other side of the connecting plate 6, a large nut 3 is sleeved, and the large nut 3 is fixed on the forward screw rod section 21. After placing a plurality of gaskets, a small nut 4 is sleeved, and the small nut 4 is fixed on the reverse screw rod section 22. After that, the bolt sleeve 5 is sleeved on the outside of the large nut 3 and the small nut 4, so that the bolt sleeve 5 The external fixing block 55 is inserted into the connecting hole 31 outside the large nut 3 for fixing. The deformable plastic layer 52 is used to set different types of nuts to be deformable, thereby reducing the gap between the nut and the bolt sleeve 5. The anti-seepage coating applied on the outside of the bolt sleeve 51 and the sealing ring 54 at the bottom of the bolt sleeve 51 isolate the nut from the external environment, thereby improving the overall anti-seepage ability of the bolt. At the same time, due to the provision of the forward screw segment 21 and the reverse screw segment 22, the seismic resistance of the connection is improved, thereby improving the anti-falling property of the bolt.

[0026] The above embodiments are intended to illustrate the present invention, not to limit the present invention. Any solution that is a simple transformation of the present invention falls within the protection scope of the present invention.

Claims

1. A double-threaded anti-falling bolt for bridges, characterized in that: The invention comprises a screw head (1), a screw rod (2), a large nut (3), a small nut (4), and a bolt sleeve (5); the screw rod (2) is fixed below the screw head (1); the screw rod (2) comprises a forward screw rod section (21) and a reverse screw rod section (22); the forward screw rod section (21) is arranged above the reverse screw rod section (22); the forward screw rod section (21) passes through a connecting plate (6) and is connected and fixed by the large nut (3); a small nut (4) is arranged below the large nut (3); the small nut (4) is connected and fixed to the reverse screw rod section (22); bolt sleeves (5) are arranged on the outside of the large nut (3) and the small nut (4).

2. A double-threaded anti-falling bolt for bridges as claimed in claim 1, characterized in that: The screw head (1) is hexagonal, and a plurality of locking teeth are provided at the bottom of the screw head (1) to increase the friction between the screw head (1) and the connecting plate (6).

3. The double-threaded anti-falling bolt for bridges according to claim 1, characterized in that: The forward screw segment (21) and the reverse screw segment (22) have external threads in opposite directions, and the diameter of the forward screw segment (21) is larger than that of the reverse screw segment (22).

4. The double-threaded anti-falling bolt for bridges according to claim 1, characterized in that: A gasket is provided between the large nut (3) and the connecting plate (6), and a connecting hole (31) is provided at the center of each of the six outer sides of the nut (3).

5. The double-threaded anti-falling bolt for bridges according to claim 1, characterized in that: A plurality of gaskets are arranged between the large nut (3) and the small nut (4).

6. The double-threaded anti-falling bolt for bridges according to claim 1, characterized in that: The bolt sleeve (5) comprises a bolt sleeve body (51), a plastic layer (52), a hollow cavity (53), a sealing ring (54), and a fixed plug-in block (55). The inner side of the bolt sleeve body (51) is provided with a plastic layer (52), the inner side of the plastic layer (52) is a hollow cavity (53), the bottom of the bolt sleeve body (51) is provided with a sealing ring (54), and the side of the bolt sleeve body (51) is provided with a fixed plug-in block (55).

7. A double-threaded anti-drop bolt for bridges as claimed in claim 6, characterized in that: The bolt sleeve (51) is coated with an anti-seepage coating on its exterior, and the sealing ring (54) is made of rubber material.

8. The double-threaded anti-drop bolt for bridges according to claim 6, characterized in that: The fixing plug block (55) matches the connecting hole (31) on the nut (3).

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