CN209838895U - Concrete bolt - Google Patents

Abstract

The utility model provides a concrete bolt, including bolt head and shank of bolt, be equipped with first screw thread and second screw thread on the shank of bolt, first screw thread and second screw thread equipartition are established on whole shank of bolt, the centre of the adjacent two teeth of first screw thread is the tooth of a second screw thread, the tooth form angle of first screw thread is 60, the tooth form angle of second screw thread is 120, the pitch of first screw thread equals the pitch of second screw thread, the external diameter of first screw thread is greater than the external diameter of second screw thread, the bolt head includes bolt head top and bolt head bottom, be connected through the curved surface between bolt head top and the bolt head bottom, the tip that bolt head bottom and shank of bolt are connected is ARC structure or inclined plane structure, be equipped with locking tooth on the terminal surface that the bolt head bottom is close to the shank of bolt.

Description

Concrete bolt

Technical Field

The utility model relates to a fastener technical field especially relates to a concrete bolt.

Background

The fastener is a mechanical part which is used for fastening and connecting and has wide application, and is widely used in the industries of energy, electronics, electrical appliances, machinery, chemical engineering, metallurgy, dies, hydraulic pressure, home furnishing and the like. The most common fasteners are bolts, nuts, etc. which perform the fastening function by a threaded or interference fit when assembled.

The concrete bolt is mainly applied to tunnel engineering, a prefabricated hole is punched on the tunnel wall, and various supports, decorative plates and other articles are fixed on the tunnel wall. Because the use environment is moist and the use requirement is high, the product has high surface hardness, reliable fastening and good corrosion resistance.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the problem that the concrete bolt fastening effect that exists among the prior art is not good, and the concrete bolt who provides.

In order to achieve the above purpose, the utility model adopts the following technical scheme: the utility model provides a concrete bolt, including bolt head and shank of bolt, be equipped with first screw thread and second screw thread on the shank of bolt, first screw thread and second screw thread equipartition are established on whole shank of bolt, the centre of two adjacent teeth of first screw thread is the tooth of a second screw thread, the tooth form angle of first screw thread is 60, the tooth form angle of second screw thread is 120, the pitch of first screw thread equals the pitch of second screw thread, the external diameter of first screw thread is greater than the external diameter of second screw thread, the bolt head includes bolt head top and bolt head bottom, be connected through the curved surface between bolt head top and the bolt head bottom, the tip that bolt head bottom and shank of bolt are connected is ARC structure or inclined plane structure, be equipped with locking tooth on the terminal surface that the bolt head bottom is close to the shank of bolt.

Preferably, the surfaces of the bolt head and the bolt shank are made of low carbon alloy steel and are coated with a zinc-chromium coating.

Preferably, the first thread has an inner diameter equal to the inner diameter of the second thread.

Preferably, the locking teeth are evenly distributed on the periphery of the bottom of the bolt head.

Preferably, the top of the bolt head comprises a central part and an outer peripheral part, wherein the central part is of a cylindrical structure, and the outer peripheral part is of a regular hexagonal prism structure which is circumscribed to the central part.

Preferably, the maximum diameter of the top of the bolt head is smaller than the maximum diameter of the bottom of the bolt head.

Preferably, the length of the bolt head is less than the length of the bolt rod.

Preferably, the end of the bolt shank is chamfered.

Compared with the prior art, the beneficial effects of the utility model are that: by adopting a large and small double-thread structure, the axial tension is effectively enhanced, so that the concrete bolt has a good fastening effect; the locking teeth are arranged on the end face, close to the bolt rod, of the bottom of the bolt head, so that the bolt is effectively prevented from rotating, and the fastening effect of the bolt is enhanced.

Drawings

Fig. 1 is a schematic structural diagram of a concrete bolt according to an embodiment of the present invention;

FIG. 2 is a left side view of the structure of FIG. 1;

FIG. 3 is a schematic diagram of the right side view of FIG. 1;

fig. 4 is a schematic view of the installation of fig. 1.

Detailed Description

In order to further understand the objects, structures, features and functions of the present invention, the following embodiments are described in detail.

Referring to fig. 1 to 3, a concrete bolt of the present invention includes a bolt head 1 and a bolt shaft 2.

The bolt rod 2 is provided with a first thread 21 and a second thread 22, the first thread 21 and the second thread 22 are uniformly distributed on the whole bolt rod 2, the middle of two adjacent teeth of the first thread 21 is the tooth of the second thread 22, the tooth form angle alpha of the first thread 21 is 60 degrees, the tooth form angle beta of the second thread 22 is 120 degrees, the thread pitch P of the first thread 21 is equal to the thread pitch P1 of the second thread 22, and the outer diameter D of the first thread 21 is larger than the outer diameter D1 of the second thread. Preferably, the inner diameter of the first thread 21 is equal to the inner diameter of the second thread 22, both d.

The bolt head 1 comprises a bolt head top 11 and a bolt head bottom 12, the bolt head top 11 is connected with the bolt head bottom 12 through a curved surface, the end part of the bolt head bottom 12 connected with the bolt rod 2 is of a cambered surface structure or an inclined surface structure, and the end surface of the bolt head bottom 12 close to the bolt rod 2 is provided with anti-loosening teeth 121. Preferably, the locking teeth 121 are evenly distributed on the circumference of the bolt head bottom 12.

In a preferred embodiment, the bolt head top portion 11 includes a central portion 111 and an outer peripheral portion 112, the central portion 111 being of a cylindrical configuration, and the outer peripheral portion 112 being of a regular hexagonal prismatic configuration circumscribing the central portion 111.

Preferably, the bolt head 1 and the bolt shank 2 of the concrete bolt are both made of a low carbon alloy steel. Further, the concrete bolt is manufactured by a nitriding process so that the concrete bolt has high hardness. Further, the surfaces of the bolt head 1 and the bolt shank 2 of the concrete bolt are coated with a zinc-chromium coating, such as Dacromet, to enhance corrosion resistance.

Preferably, the maximum diameter of the head top 11 of the bolt is smaller than the maximum diameter of the bottom 12 of the bolt head.

Preferably, the length L of the bolt head 1 is smaller than the length L1 of the bolt shaft 2.

Preferably, the end of the bolt shank 2 is provided with a chamfer 23 to facilitate assembly.

The working principle is as follows: referring to fig. 4, a prefabricated hole having the same minor diameter d as the thread is drilled in the wall of the tunnel, and then the fastened workpiece is fixed to the wall by the concrete bolt. Because the surface hardness of the bolt is higher than that of cement sand stone, the bolt can be smoothly screwed into a wall, and meanwhile, the large and small double-thread structure is adopted, so that the axial tension is effectively enhanced, and a fastened workpiece is firm.

And (3) verifying the effect of the concrete bolt:

get 10 concrete bolts, bore 10 holes with bolt matched with on the concrete standard sample piece, on being fixed part cover in the bolt, assemble the moment of torsion requirement with the torque wrench, observe the bolt and whether have the rotation phenomenon, the result is as follows: no rotation phenomenon occurs in 10 concrete bolts.

Through experimental effect verification, the utility model discloses a concrete bolt does not have the rotation phenomenon in assembling process, has satisfied the product design requirement completely.

The concrete bolt of the utility model effectively enhances the axial tension by adopting the structure of big and small double threads, so that the concrete bolt has good fastening effect; the locking teeth are arranged on the end face, close to the bolt rod, of the bottom of the bolt head, so that the bolt is effectively prevented from rotating, and the fastening effect of the bolt is enhanced.

The present invention has been described in relation to the above embodiments, which are only examples for implementing the present invention. It should be noted that the disclosed embodiments do not limit the scope of the invention. On the contrary, all changes and modifications which do not depart from the spirit and scope of the present invention are deemed to fall within the scope of the present invention.

Claims (8)

1. A concrete bolt comprises a bolt head and a bolt rod, and is characterized in that the bolt rod is provided with a first thread and a second thread, the first thread and the second thread are uniformly distributed on the whole bolt rod, the middle of two adjacent teeth of the first thread is a tooth of the second thread, the profile angle of the first thread is 60 °, the profile angle of the second thread is 120 °, the pitch of the first thread being equal to the pitch of the second thread, the first thread having an outer diameter greater than the outer diameter of the second thread, the bolt head comprises a bolt head top part and a bolt head bottom part, the bolt head top part is connected with the bolt head bottom part through a curved surface, the bolt head is characterized in that the end part of the bottom of the bolt head, which is connected with the bolt rod, is of a cambered surface structure or an inclined surface structure, and the end surface of the bottom of the bolt head, which is close to the bolt rod, is provided with anti-loosening teeth.

2. A concrete bolt according to claim 1, wherein the surfaces of the bolt head and the bolt shank, which are made of low carbon alloy steel, are coated with a zinc-chromium coating.

3. A concrete bolt according to claim 1, wherein the internal diameter of the first thread is equal to the internal diameter of the second thread.

4. A concrete bolt according to claim 1, wherein the locking teeth are evenly distributed on the periphery of the bottom of the bolt head.

5. A concrete bolt according to claim 1 wherein the top of the bolt head includes a central portion of cylindrical configuration and an outer peripheral portion of regular hexagonal prismatic configuration circumscribing the central portion.

6. A concrete bolt according to claim 1, wherein the maximum diameter of the top of the bolt head is less than the maximum diameter of the bottom of the bolt head.

7. A concrete bolt according to claim 1, wherein the length of the bolt head is less than the length of the bolt shank.

8. A concrete bolt according to claim 1, wherein the end of the shank of the bolt is chamfered.