Bolt body and self-tapping expansion bolt

Abstract

The utility model relates to the technical field of fasteners, and provides a bolt body and a self-tapping expansion bolt, the bolt body is suitable for being matched with an expansion pipe, and the bolt body comprises a first section and a second section which are coaxially connected; the end, away from the second section, of the first section is provided with a connecting part used for connecting a drilling machine. An end is formed at the end, away from the first section, of the second section, the size of the end is larger than the inner diameter of the expansion pipe, and the end is used for abutting against the end of the expansion pipe. The periphery of the first section is provided with threads, and the periphery of the second section is provided with a spiral guide groove. Through the arrangement, wall slag generated in the drilling process can be effectively guided out, the drilling speed and depth are prevented from being affected, and the drilling efficiency is improved; meanwhile, the wall slag filled between the gap between the bolt body and the expansion pipe can prevent the expansion pipe from deforming inwards in the fastening process, the efficiency of outward deformation of the expansion pipe can be improved to the maximum extent due to filling of the wall slag, the expansion pipe can be fully expanded only through relatively small displacement of the locking nut, and the length of the portion, exposed out of the wall, of the bolt body is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of fasteners, in particular to a bolt body and a self-tapping expansion bolt. Background Art

[0002] Compared with traditional expansion bolts, self-drilling expansion bolts are a type of bolt that does not require separate drilling with an electric drill and integrates drilling and expansion fastening into one. By omitting the drill tool and drilling, hole entry and installation processes, the overall installation efficiency is improved.

[0003] In related technologies, self-drilling expansion bolts are generally drilled by a drill at the end of the bolt body. During the drilling process, the expansion tube enters the drill hole. After the drilling is completed, the expansion tube is driven to move by screwing the nut at the tail of the bolt body to expand the expansion tube, thereby realizing the installation of the self-drilling expansion bolt.

[0004] However, in actual applications, it was found that during the drilling process of the self-drilling expansion bolt, the presence of the expansion tube made it difficult to remove the wall debris. When drilling to a certain depth, due to excessive slag blockage, the rotational resistance increased, making it impossible to continue drilling, affecting the drilling speed and depth of the self-drilling expansion bolt. Utility Model Content

[0005] The utility model provides a bolt body and a self-drilling expansion bolt, which are used to solve the defect in the prior art that the drilling speed and depth of the self-drilling expansion bolt are affected by the difficulty in extracting wall debris. The utility model can effectively extract the wall debris during the drilling process to avoid affecting the drilling speed and depth. In addition, the wall debris can be used to prevent the expansion tube from deforming inwardly, thereby improving the deformation efficiency of the expansion tube, thereby shortening the axial displacement of the fastening nut and reducing the exposed length of the bolt body.

[0006] The utility model provides a bolt body suitable for cooperating with an expansion tube, wherein the bolt body comprises: a first section and a second section which are coaxially connected;

[0007] The end of the first section away from the second section is provided with a connecting portion for connecting to a drilling rig;

[0008] An end cap is formed at the end of the second section away from the first section. The end cap has a size larger than the inner diameter of the expansion tube and is used to abut against the end of the expansion tube.

[0009] A thread is provided on the outer circumference of the first section, and a spiral guide groove is provided on the outer circumference of the second section.

[0010] According to a bolt body provided by the present invention, the outer diameter of one end of the second section away from the first section gradually expands to form the tapered end head.

[0011] According to a bolt body provided by the utility model, the first section and the second section are formed in one piece.

[0012] According to a bolt body provided by the utility model, the connecting portion is configured as a polygonal columnar structure coaxially arranged with the first section.

[0013] According to a bolt body provided by the present invention, an end portion of the first section away from the second section is provided with an embedding groove with a polygonal cross-section, and the embedding groove is coaxially arranged with the first section to form the connecting portion.

[0014] The utility model also provides a self-drilling expansion bolt, which comprises at least an expansion tube, a locking nut, a drill bit and any one of the bolt bodies described above;

[0015] The drill bit is connected to an end of the end head away from the connecting portion;

[0016] The expansion tube is open at both ends and has a strip-shaped notch extending in the axial direction at one end; the expansion tube is slidably sleeved on the outside of the bolt body in the axial direction, and the end with the strip-shaped notch abuts against the end of the bolt body;

[0017] The locking nut is threadedly connected to the first section and acts on an end of the expansion tube away from the end head, so as to drive the expansion tube to slide toward the end head.

[0018] According to the self-tapping expansion bolt provided by the utility model, it also includes a washer, which is sleeved outside the first section and located between the locking nut and the expansion tube.

[0019] According to the self-drilling expansion bolt provided by the utility model, the drill bit and the end head are detachably connected or integrally formed.

[0020] According to the self-tapping expansion bolt provided by the utility model, a slot is provided at one end of the end head away from the connecting portion, and the drill bit is embedded in the slot.

[0021] According to the self-tapping expansion bolt provided by the utility model, a plurality of strip-shaped notches are evenly distributed around the axis of the expansion tube.

[0022] According to the self-drilling expansion bolt provided by the utility model, the drill bit is in an I-shape or a X-shape.

[0023] According to the self-tapping expansion bolt provided by the utility model, the nut is a hexagonal nut.

[0024] The bolt body and self-drilling expansion bolt provided by the present invention can, during the drilling process of the self-drilling expansion bolt, allow wall debris to be introduced into the interior of the expansion tube along the bolt guide groove, a portion of the wall debris can be discharged through the strip-shaped notch on the expansion tube, and the other portion of the wall debris is filled between the bolt body and the expansion tube. In this way, the wall debris generated during the drilling process can be effectively guided out, thereby avoiding affecting the drilling speed and depth and improving the drilling efficiency. At the same time, the wall debris filled between the bolt body and the expansion tube can prevent the expansion tube from deforming inwards during the tightening process, and due to the filling of the wall debris, the efficiency of the expansion tube in deforming outwards can be maximized. The locking nut only requires a relatively small displacement to achieve full expansion of the expansion tube, thereby effectively reducing the length of the bolt body exposed to the wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 It is a structural schematic diagram of a bolt body provided by an embodiment of the utility model.

[0027] Figure 2 It is a structural schematic diagram of a self-tapping expansion bolt provided by an embodiment of the utility model.

[0028] Figure 3 It is an exploded view of the self-tapping expansion bolt provided by an embodiment of the utility model.

[0029] Figure 4 It is a cross-sectional view of a self-tapping expansion bolt provided in an embodiment of the utility model.

[0030] Reference numerals:

[0031] 10. First section; 11. Second section; 110. Spiral guide groove; 12. Connecting portion; 13. End; 20. Expansion tube; 200. Strip notch; 30. Locking nut; 40. Drill bit; 50. Washer. DETAILED DESCRIPTION

[0032] To make the purpose, technical solutions, and advantages of the present invention more clear, the following will be combined with the accompanying drawings to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] In order to facilitate the understanding of the self-drilling expansion bolt provided by the embodiment of the present invention, its application background is first introduced. The self-drilling expansion bolt is a bolt that integrates drilling and expansion fastening. During the installation process, it is drilled by the drill bit at the end of the bolt body. During the drilling process, the expansion tube enters the drill hole. After the drilling is completed, the expansion tube is driven to move by screwing the nut at the tail of the bolt body to expand the expansion tube, thereby realizing the installation of the self-drilling expansion bolt.

[0034] However, in actual applications, it was found that during the drilling process of the self-drilling expansion bolt, the presence of the expansion tube made it difficult to remove the wall debris. When drilling to a certain depth, due to excessive slag blockage, the rotational resistance increased, making it impossible to continue drilling, affecting the drilling speed and depth of the self-drilling expansion bolt.

[0035] In response to the above problems, the embodiments of the present invention provide a bolt body and a self-drilling expansion bolt, which can effectively guide out wall debris during the drilling process to avoid affecting the drilling speed and depth; in addition, the wall debris can be used to prevent the expansion tube from deforming inward, thereby improving the deformation efficiency of the expansion tube, thereby shortening the axial displacement of the fastening nut and reducing the length of the bolt body exposed to the wall.

[0036] The following combination Figures 1-4 The present invention describes a bolt body and a self-tapping expansion bolt.

[0037] Reference Figures 1 to 4 , a bolt body, which can cooperate with the expansion tube 20 and the locking nut 30 of the self-tapping expansion bolt, and the expansion tube 20 is sleeved outside the bolt body; the bolt body includes a first section 10 and a second section 11 connected coaxially; wherein, a connecting portion 12 is provided at the end of the first section 10 away from the second section 11, for connecting to a drilling rig, and an end head 13 is formed at the end of the second section 11 away from the first section 10, the size of the end head 13 is larger than the inner diameter of the expansion tube 20, and is used to abut against the end of the expansion tube 20, and the end of the end head 13 away from the connecting portion 12 is used to connect a drill bit 40; a thread is provided on the outer circumference of the first section 10, and the locking nut 30 is threadedly connected to the first section 10, suitable for applying force to the end of the expansion tube 20 away from the end head 13, and a spiral guide groove 110 is provided on the outer circumference of the second section 11.

[0038] In a specific application scenario, the bolt body is passed through the expansion tube 20 of the self-drilling expansion bolt, and one end of the expansion tube 20 along the axial direction abuts against the end head 13 at the end of the second section 11. The locking nut 30 is threadedly connected to the first section 10 to apply force to the end of the expansion tube 20 away from the end head 13, and the drill bit 40 is connected to the end of the end head 13 away from the connecting portion 12; when installing the self-drilling expansion bolt, it is connected to the drilling rig through the connecting portion 12 at the end of the first section 10, the drill bit 40 abuts against the construction wall, the drilling rig is started, and the drilling rig drives the drill rod to rotate for drilling operations, and the expansion tube 20 enters the drill hole. After the drilling is completed, the locking nut 30 is screwed with a tool, and the locking nut 30 drives the expansion tube 20 to move axially toward the end head 13. Under the joint action of the end head 13 and the locking nut 30, the expansion tube 20 is expanded, thereby realizing the installation of the self-drilling expansion bolt.

[0039] Compared with the related art, during the drilling process, the wall debris can be introduced into the interior of the expansion tube 20 along the bolt guide groove. A part of the wall debris can be discharged through the strip notch 200 on the expansion tube 20, and the other part of the wall debris is filled between the bolt body and the expansion tube 20. In this way, the wall debris generated during the drilling process can be effectively discharged, avoiding affecting the drilling speed and depth, and improving the drilling efficiency. At the same time, the wall debris filled in the gap between the bolt body and the expansion tube 20 can prevent the expansion tube 20 from deforming inward during the tightening process. Due to the filling of the wall debris, the efficiency of the outward deformation of the expansion tube 20 can be maximized. The locking nut 30 only needs a relatively small displacement to achieve full expansion of the expansion tube 20, thereby effectively reducing the length of the bolt body exposed to the wall.

[0040] In some optional embodiments, the specific material, size and other parameters of the bolt body can be flexibly designed according to actual needs, and are not specifically limited in the embodiments of the present invention.

[0041] In one embodiment of the present invention, in order to ensure structural strength, the first section 10 and the second section 11 of the bolt body are integrally formed, and the outer diameters of the first section 10 and the second section 11 may be the same or different.

[0042] For example, the outer diameter of the first section 10 can be made smaller than that of the second section 11 , so that the gap between the first section 10 and the expansion tube 20 can be increased, and part of the wall debris can be discharged through the gap between the first section 10 and the expansion tube 20 during the drilling process.

[0043] It should be noted that, since the locking nut 30 and the expansion tube 20 are in a relaxed state during the drilling process, the removal of the wall debris is not affected. Furthermore, when the locking nut 30 is tightened with a wrench, the preload applied by the locking nut 30 on the expansion tube 20 is sufficient to promote axial sliding of the expansion tube 20, preventing the wall debris from affecting the sliding of the expansion tube 20. During the tightening process, the locking nut 30 pushes the expansion tube 20 and the wall debris toward the end 13 simultaneously. The wall debris converges at the end 13 of the bolt body, pushing the expansion tube 20 outward, further improving the efficiency of the outward deformation of the expansion tube 20. With the above-described solution, only the effect of the diameter on the strength of the first section 10 needs to be considered. Therefore, it is sufficient to ensure that the strength of the first section 10 meets the requirements.

[0044] In the embodiment of the present invention, in order to ensure the overall structural strength of the bolt body, the outer diameters of the first section 10 and the second section 11 are equal.

[0045] In one embodiment of the present invention, the outer diameter of the second section 11 at the end away from the first section 10 gradually expands, forming a tapered end cap 13. This configuration allows the locking nut 30 to push the expansion tube 20 axially toward the end cap 13 during tightening. Because the outer diameter of the end cap 13 gradually expands to form a tapered shape, the end of the expansion tube 20 gradually expands as it moves axially toward the end cap 13, thereby improving the expansion efficiency of the expansion tube 20.

[0046] A connecting portion 12 is provided at one end of the first section 10 away from the second section 11 for connecting to a drilling rig. The connecting portion 12 may be in different forms according to different actual needs.

[0047] In one embodiment of the present invention, the connecting portion 12 is configured as a polygonal columnar structure coaxially arranged with the first section 10, and is used to adapt to the bayonet at the power output end of the drilling rig. The connecting portion 12 and the first section 10 can be fixed by welding or integrally formed. The specific configuration can be based on actual needs. In this embodiment, in order to ensure structural strength, the connecting portion 12 and the first section 10 are integrally formed. When installing the self-tapping expansion bolt, the connecting portion 12 of the polygonal columnar structure is engaged with the polygonal bayonet at the power output end of the drilling rig, so that the drilling rig can drive the bolt body to rotate.

[0048] However, with the above-mentioned technical solution, the cylindrical connecting portion 12 undoubtedly increases the length of the bolt body exposed from the wall, hindering subsequent processes. To address this issue, another embodiment of the present invention provides a polygonal groove at the end of the first section 10 away from the second section 11. The groove is coaxial with the first section 10 to form the aforementioned connecting portion 12. When installing the self-tapping expansion bolt, the polygonal groove-structured connecting portion 12 engages with the polygonal clamping column at the power output end of the drilling rig, allowing the drill to drive the bolt body to rotate.

[0049] It can be understood that the shape of the connecting portion 12 will also be different depending on the specific form of the power output end of the drilling rig. For example, when the cross-section of the power output section of the drilling rig is a quadrilateral, the cross-section of the connecting portion 12 is correspondingly set to a quadrilateral. When the cross-section of the power output section of the drilling rig is a hexagon, the cross-section of the connecting portion 12 is correspondingly set to a hexagon. In other words, the specific shape of the connecting portion 12 can be set according to actual needs, and the specific shape of the connecting portion 12 is not limited in the embodiment of the utility model.

[0050] The self-tapping expansion bolt provided by the present invention is described below. The self-tapping expansion bolt described below and the bolt body described above can be referred to each other.

[0051] Reference Figures 1 to 4 A self-tapping expansion bolt comprises at least an expansion tube 20, a locking nut 30, a drill bit 40, and a bolt body provided by any of the above embodiments; wherein the drill bit 40 is connected to the end of the end head 13 away from the connecting portion 12; the expansion tube 20 is open at both ends and one end is provided with a strip notch 200 extending in the axial direction; in the axial direction, the expansion tube 20 can be slidably arranged outside the bolt body, and the end provided with the strip notch 200 abuts against the end head 13 of the bolt body; the locking nut 30 is threadedly connected to the first section 10 of the bolt body and acts on the end of the expansion tube 20 away from the end head 13, used to drive the expansion tube 20 to slide toward the end head 13.

[0052] In actual installation of the self-drilling expansion bolt, the connecting part 12 is connected to the drilling rig, the drill bit 40 is abutted against the construction wall, the drilling rig is started, and the bolt body drives the drill bit 40 to rotate to drill a hole, and the expansion tube 20 enters the drill hole. After the drilling is completed, the locking nut 30 is tightened with a wrench or other tool. The locking nut 30 drives the expansion tube 20 to move axially toward the end head 13. Under the joint action of the end head 13 and the locking nut 30, the expansion tube 20 expands from the strip notch 200.

[0053] In an embodiment of the present invention, the drill bit 40 and the end head 13 of the bolt body can be connected in a detachable manner or can be integrally formed. The specific selection can be made according to actual needs.

[0054] However, in actual applications, in order to ensure the strength of the drill bit 40, the drill bit 40 and the bolt body are made of different materials. Therefore, in this embodiment, a groove is provided at the end of the end head 13 away from the connecting portion 12, and the drill bit 40 is embedded in the groove, thereby realizing the assembly of the drill bit 40 and the end head 13.

[0055] In some embodiments, the drill bit 40 can be set to a straight line or a cross shape according to actual needs, and there is no specific limitation in the embodiments of the present invention.

[0056] In one embodiment of the present invention, a plurality of strip-shaped notches 200 are evenly distributed around the axis of the expansion tube 20. Thus, when the locking nut 30 pushes the expansion tube 20 to slide toward the end 13, the expansion tube 20 can expand evenly from the strip-shaped notches 200, thereby improving the efficiency of the outward deformation of the expansion tube 20.

[0057] In one embodiment of the present invention, the self-tapping expansion bolt further includes a washer 50, which is sleeved onto the outside of the first section 10 and positioned between the locking nut 30 and the expansion tube 20. With this arrangement, when tightening the expansion bolt, the locking nut 30 is turned, which acts on the washer 50. Pushed by the washer 50, the expansion tube 20 moves toward the end 13 of the bolt body and expands. The washer 50 disperses the pressure exerted by the locking nut 30 on the expansion tube 20, reducing local stress concentration and preventing damage to the expansion tube 20 or the locking nut 30 due to excessive local force.

[0058] In some embodiments of the present invention, the locking nut 30 can be selected as a square nut, a hexagonal nut, etc. The specific one can be selected according to actual needs and is not specifically limited.

[0059] It is understood that those skilled in the art may combine and integrate different embodiments or examples and features of different embodiments or examples described in this specification without mutual contradiction.

[0060] By using the bolt body and self-drilling expansion bolt provided by the present invention, during the drilling process of the self-drilling expansion bolt, wall debris can be introduced into the interior of the expansion tube 20 along the bolt guide groove, and a portion of the wall debris can be discharged through the strip notch 200 on the expansion tube 20, while the other portion of the wall debris is filled between the bolt body and the expansion tube 20. In this way, the wall debris generated during the drilling process can be effectively guided out, thereby avoiding affecting the drilling speed and depth and improving the drilling efficiency. At the same time, the wall debris filled in the gap between the bolt body and the expansion tube 20 can prevent the expansion tube 20 from deforming inward during the tightening process, and due to the filling of the wall debris, the efficiency of the outward deformation of the expansion tube 20 can be maximized. The locking nut 30 only requires a relatively small displacement to achieve full expansion of the expansion tube 20, thereby effectively reducing the length of the bolt body exposed to the wall.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A bolt body, characterized in that: Suitable for cooperating with an expansion tube (20), the bolt body comprises: a first section (10) and a second section (11) coaxially connected; The end of the first section (10) away from the second section (11) is provided with a connecting portion (12) for connecting to a drilling rig; The end of the second section (11) away from the first section (10) is formed with an end head (13), the size of the end head (13) is larger than the inner diameter of the expansion tube (20), and is used to abut against the end of the expansion tube (20); A screw thread is provided on the outer circumference of the first section (10), and a spiral guide groove (110) is provided on the outer circumference of the second section (11).

2. The bolt body according to claim 1, characterized in that The outer diameter of one end of the second section (11) away from the first section (10) gradually expands to form the tapered end head (13).

3. The bolt body according to claim 1, characterized in that: The first section (10) and the second section (11) are integrally formed.

4. The bolt body according to claim 1, wherein: The connecting portion (12) is configured as a polygonal columnar structure coaxially arranged with the first section (10).

5. The bolt body according to claim 1, wherein: An end portion of the first section (10) away from the second section (11) is provided with an embedding groove with a polygonal cross section, and the embedding groove is coaxially arranged with the first section (10) to form the connecting portion (12).

6. A self-tapping expansion bolt, characterized in that: At least comprising an expansion tube (20), a locking nut (30), a drill (40) and a bolt body according to any one of claims 1 to 5; The drill bit (40) is connected to an end of the end head (13) facing away from the connecting portion (12); The expansion tube (20) is open at both ends and is provided with a strip-shaped notch (200) extending in the axial direction at one end; in the axial direction, the expansion tube (20) is slidably sleeved outside the bolt body, and the end provided with the strip-shaped notch (200) abuts against the end head (13) of the bolt body; The locking nut (30) is threadedly connected to the first section (10) and acts on the end of the expansion tube (20) away from the end head (13) to drive the expansion tube (20) to slide toward the end head (13).

7. The self-drilling expansion bolt according to claim 6, characterized in that: It also includes a washer (50), which is sleeved outside the first section (10) and located between the locking nut (30) and the expansion tube (20).

8. The self-tapping expansion bolt according to claim 6, characterized in that: The drill bit (40) and the end head (13) are detachably connected or integrally formed.

9. The self-drilling expansion bolt according to claim 8, characterized in that: An end of the end head (13) facing away from the connecting portion (12) is provided with a slot, and the drill bit (40) is embedded in the slot.

10. The self-tapping expansion bolt according to claim 6, characterized in that: A plurality of strip-shaped notches (200) are evenly distributed around the axis of the expansion tube (20).

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