Novel self-drilling and self-locking bolting-grouting anchor rod

Abstract

The utility model provides a novel self-drilling and self-locking bolting-grouting anchor rod which comprises a drill bit, a middle rod, a connecting sleeve for connecting the drill bit and the middle rod, a drill rod and a prestress nut, and the connecting sleeve is connected with the middle rod through a pawl mechanism. The upper portion of the middle rod is further provided with threads and is in threaded connection with the upper portion of the expansion shell on the outer side through the threads, and the lower portion of the middle rod is of an inverted circular truncated cone structure and is matched and attached to the lower portion of the expansion shell. The anchor rod has the advantages of being convenient to operate, high in labor efficiency, good in supporting effect, capable of achieving full-length anchoring and the like.

Description

Technical Field

[0001] This utility model relates to an anchor bolt, and more particularly to a novel self-drilling and self-locking anchor bolt. Background Technology

[0002] Coal, as one of my country's most important energy sources, will continue to be a crucial resource for a long time. Coal mine production must be safe and efficient. As coal mines are gradually mined deeper, underground ground stress increases, making the support systems for thick coal seams, "three-soft" coal seams, and soft rock inadequate. Therefore, a fast, safe, and efficient support method is essential. Traditional underground roadway support methods, such as U-shaped steel, I-beams, and end-anchored bolts, are labor-intensive, have poor support effects, and are unsuitable for deep coal mining. U-shaped steel and I-beam supports have been phased out. End-anchored bolt support has also gradually revealed its drawbacks. For example, it involves multiple construction steps: drilling, placing resin anchoring agent, rotating the bolt, and applying pre-tightening force. This is inconvenient for workers, labor-intensive, and poses safety risks, making it unsuitable for safe and efficient coal mining. Furthermore, traditional bolt construction involves many steps; encountering fractured surrounding rock, loose coal seams, or situations where drilling is impossible, anchoring agent cannot be installed, and construction becomes impossible, all while maintaining high labor intensity.

[0003] To solve the existing technical problems, there is an urgent need for an anchor bolt that is easy to operate, has high labor efficiency, provides good support, and is self-drilling and self-locking. Utility Model Content

[0004] The purpose of this utility model is to provide a novel self-drilling and self-locking anchor rod, which includes: a drill bit located at the upper end, an intermediate rod located below the drill bit, a connecting sleeve connecting the drill bit and the intermediate rod, a drill rod connected to the lower end of the intermediate rod, and a prestressed nut near the lower end of the drill rod. The drill bit, the intermediate rod, the connecting sleeve, and the drill rod are all hollow structures and are interconnected.

[0005] The connecting sleeve and the intermediate rod are connected by a pawl mechanism. The upper part of the intermediate rod is also provided with a thread, and the thread is used to connect with the upper part of the outer expansion shell. The lower part of the intermediate rod is an inverted frustum structure and matches and fits the lower part of the expansion shell.

[0006] Preferably, the intermediate rod has multiple through holes above its inverted frustum structure, and the expansion shell also has an arc-shaped groove at the corresponding position of the through holes.

[0007] Preferably, the expansion shell and the connecting sleeve are connected as one unit.

[0008] Preferably, the pawl mechanism includes a pawl and a spring connecting the pawl.

[0009] Preferably, the pawl is square in shape with one end being a smooth arc and the other end being a right angle.

[0010] Preferably, the pawl mechanism is located at the upper end of the intermediate rod and operates in conjunction with the one-way groove at the lower part of the connecting sleeve.

[0011] Preferably, the intermediate rod and the drill rod are connected by a first pin.

[0012] Preferably, the prestressed nut is connected to the drill rod by a second pin, and a sealing sleeve is also provided between the prestressed nut and the drill rod.

[0013] Preferably, the thread is a fine-pitch thread.

[0014] Preferably, the outer side of the expansion shell has a rough structure.

[0015] It should be understood that the foregoing general description and the subsequent detailed description are illustrative and explanatory, and should not be used as limitations on the content claimed by this utility model. Attached Figure Description

[0016] Referring to the accompanying drawings, further objects, functions, and advantages of this invention will be clarified through the following description of embodiments of this invention, wherein:

[0017] Figure 1 This schematic diagram illustrates the structure of a novel self-drilling and self-locking anchor bolt according to the present invention.

[0018] Figure 2 This schematic diagram illustrates the pawl mechanism structure of a novel self-drilling and self-locking anchor bolt according to the present invention.

[0019] Figure 3 The schematic diagram illustrates the structure of a novel self-drilling and self-locking anchor bolt of this utility model when its expansion shell expands. Detailed Implementation

[0020] The objectives and functions of this invention, as well as the methods for achieving these objectives and functions, will be clarified by referring to exemplary embodiments. However, this invention is not limited to the exemplary embodiments disclosed below; it can be implemented in various forms. The purpose of this specification is merely to help those skilled in the art to comprehensively understand the specific details of this invention.

[0021] In the following description, embodiments of the present invention will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar parts, or the same or similar steps.

[0022] Figure 1The illustration shows a novel self-drilling and self-locking anchor bolt of the present invention. The novel self-drilling and self-locking anchor bolt includes: a drill bit 1 located at the upper end, an intermediate rod 2 located below the drill bit 1, a connecting sleeve 3 connecting the drill bit 1 and the intermediate rod 2, a drill rod 4 connected to the lower end of the intermediate rod 2, and a prestressed nut 5 near the lower end of the drill rod 4. The drill bit 1, the intermediate rod 2, the connecting sleeve 3 and the drill rod 4 are all hollow structures and are interconnected.

[0023] The connecting sleeve 3 is connected to the intermediate rod 2 by a ratchet mechanism 6. The upper part of the intermediate rod 2 is also provided with a thread 7, which is threaded to the upper part of the outer expansion shell 8. The lower part of the intermediate rod 2 is an inverted frustum structure and matches and fits with the lower part of the expansion shell 8. More preferably, the expansion shell 8 is also movably connected to the connecting sleeve 3 as a whole, for example, by a snap-fit ​​connection.

[0024] When the intermediate rod 2 rotates forward, the pawl mechanism 6 locks and drives the drill bit 1 to rotate, thereby achieving the purpose of power transmission and drilling; when the intermediate rod 2 rotates in reverse, the pawl mechanism 6 idles, and the drill bit 1 also stops drilling. At this time, the reverse rotation of the intermediate rod 2 causes the expansion shell 8 to move upward, and under the obstruction of the inverted frustum structure, it expands, thereby further achieving the anchoring effect.

[0025] Multiple through holes 9 are provided above the inverted frustum structure of the intermediate rod 2 to facilitate subsequent grouting operations; the expansion shell 8 also has an arc-shaped groove 10 at the corresponding position of the through holes 9, which reduces the strength of the expansion shell 8 at the arc-shaped groove 10, so as to expand outward with the arc-shaped groove 10 as a fulcrum. More preferably, a rough structure is also provided on the outer side of the expansion shell 8 to enhance its frictional resistance with the hole wall.

[0026] like Figure 2 As shown, the pawl mechanism 6 includes a pawl 61 and a spring 62 connecting the pawl 61. The pawl 61 is generally square with one end being a smooth arc and the other end being a right angle. The pawl mechanism 6 is located at the upper end of the intermediate rod 2 and operates in conjunction with the one-way slide groove 21 at the lower part of the connecting sleeve 3. A blocking block is provided in the one-way slide groove 21. One side of the blocking block is a gentle slope, and the other side is a steep right-angle slope. When the pawl mechanism 6 rotates clockwise, the right-angle side of the pawl 61 is blocked by the steep slope of the blocking block. When the pawl mechanism 6 rotates counterclockwise, the smooth arc side of the pawl 61 smoothly transitions on the gentle slope of the blocking block, thereby achieving the purpose of locking transmission and idling expansion.

[0027] The intermediate rod 2 is connected to the drill rod 4 by the first pin 11, and the prestressed nut 5 is connected to the drill rod 4 by the second pin 12. In addition, a sealing sleeve 13 is provided between the prestressed nut 5 and the drill rod 4 to prevent leakage during grouting.

[0028] The steps for using this novel self-drilling and self-locking anchor bolt are as follows:

[0029] 1. First, install the new self-drilling and self-locking anchor bolt of this utility model on the anchor bolt machine adapter, turn on the water and turn the anchor bolt machine forward. The anchor bolt body enters the coal and rock strata. When the anchor bolt support plate 15 on the front end face of the prestressed nut 5 is in close contact with the coal and rock surface, stop rotating the anchor bolt machine.

[0030] 2. Then, the anchor bolting machine presses against the anchor bolt and reverses. At this time, the intermediate rod 4 and thread 7 rotate freely. The expansion shell 8 does not rotate due to frictional resistance or clamping resistance, but it will move upward under the drive of thread 7 and be further expanded by the inverted frustum structure (e.g., Figure 3 (as shown), thereby achieving the purpose of anchoring.

[0031] 3. Finally, the anchor bolting machine continues to rotate, applying a certain prestress to the anchor bolt and simultaneously cutting off the second pin 12. After the drilling and installation are completed, the anchor bolt is grouted. The grout is injected through the drill rod 4, the intermediate rod 2, and the through hole 9 to reach the space in use, thereby forming a full-length anchor.

[0032] This utility model discloses a novel self-drilling and self-locking anchor bolt using a hollow anchor bolt. A locking device is installed at the end of the anchor bolt, which includes a built-in drill bit. The hollow anchor bolt body serves as the drill rod, allowing for direct installation with an anchor bolting machine. After drilling to the bottom, the locking device at the end locks the borehole, giving the anchor bolt initial prestress. It can be grouted using an adapter to achieve full-length anchoring, followed by secondary pre-tightening. This utility model allows for single anchor bolts to be 2.5 to 3.0 meters long, or they can be combined into bolts 3.0 to 5.0 meters long (each 1.0 meter long, connected by a connecting sleeve). This solves the problem of anchor bolts being unable to support medium-thick coal seams, providing rapid support for roof collapse zones and eliminating safety hazards. This utility model discloses a novel self-drilling and self-locking anchor bolt with a wide range of applications, such as coal mines, rock tunnels, tunnel repair, collapse treatment, tunnels, slopes, and hoisting systems. As long as the anchor head can be rooted in the rock, the anchor bolt can generate initial anchoring force in one step and support the surrounding rock. It eliminates the need for drilling, installing anchoring agent, mixing, and pre-tightening, reducing labor intensity and improving labor efficiency. Because the anchor bolt is hollow, grout can be injected from the tail end to form a full-length anchor bolt. It has many advantages such as convenient operation, high labor efficiency, and good support effect.

[0033] The accompanying drawings are schematic only and not to scale. Although the present invention has been described in conjunction with preferred embodiments, it should be understood that the scope of protection of the present invention is not limited to the embodiments described herein.

[0034] Other embodiments of the present invention will be readily conceived and understood by those skilled in the art in conjunction with the description and practice disclosed herein. The description and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are defined by the claims.

Claims

1. A novel self-drilling and self-locking anchor bolt, comprising: The system comprises a drill bit (1) at the upper end, an intermediate rod (2) below the drill bit (1), a connecting sleeve (3) connecting the drill bit (1) and the intermediate rod (2), a drill rod (4) connected to the lower end of the intermediate rod (2), and a prestressed nut (5) near the lower end of the drill rod (4). The drill bit (1), the intermediate rod (2), the connecting sleeve (3), and the drill rod (4) are all hollow structures and interconnected. The connecting sleeve (3) is connected to the intermediate rod (2) by a pawl mechanism (6); The upper part of the intermediate rod (2) is also provided with a thread (7) and is threadedly connected to the upper part of the outer expansion shell (8) through the thread (7). The lower part of the intermediate rod (2) is an inverted frustum structure and matches and fits the lower part of the expansion shell (8).

2. The novel self-drilling and self-locking anchor bolt according to claim 1, characterized in that: The intermediate rod (2) has multiple through holes (9) above its inverted frustum structure, and the expansion shell (8) also has an arc-shaped groove (10) at the corresponding position of the through holes (9).

3. The novel self-drilling and self-locking anchor bolt according to claim 2, characterized in that: The expansion shell (8) and the connecting sleeve (3) are connected as one unit.

4. The novel self-drilling and self-locking anchor bolt according to claim 3, characterized in that: The pawl mechanism (6) includes a pawl (61) and a spring (62) connecting the pawl (61).

5. The novel self-drilling and self-locking anchor bolt according to claim 4, characterized in that: The pawl (61) is square in shape with one side of the end being a smooth arc and the other side being a right angle.

6. The novel self-drilling and self-locking anchor bolt according to claim 5, characterized in that: The pawl mechanism (6) is located at the upper end of the intermediate rod (2) and operates in conjunction with the one-way slide groove (21) at the lower part of the connecting sleeve (3).

7. The novel self-drilling and self-locking anchor bolt according to claim 6, characterized in that: The intermediate rod (2) is connected to the drill rod (4) by a first pin (11).

8. The novel self-drilling and self-locking anchor bolt according to claim 7, characterized in that: The prestressed nut (5) is connected to the drill rod (4) by a second pin (12), and a sealing sleeve (13) is also provided between the prestressed nut (5) and the drill rod (4).

9. The novel self-drilling and self-locking anchor bolt according to claim 8, characterized in that: The thread (7) is a fine thread.

10. The novel self-drilling and self-locking anchor bolt according to claim 9, characterized in that: The outer side of the expansion shell (8) is provided with a rough structure.

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