Suspended self-drilling anchor rod device

Abstract

A suspended self-drilling anchor rod device includes an anchor rod, a drill bit, a retaining member, and a reverse clamping claw. The drill bit is disposed at an end portion of the anchor rod, the retaining member is fixed to the anchor rod, and the reverse clamping claw is located between the retaining member and the drill bit. The reverse clamping claw includes a sleeve and claw bodies, the sleeve is sleeved on the anchor rod and spaced apart from the anchor rod, the claw bodies are arranged around the sleeve, with connection end portions of the claw bodies being fixedly connected to the sleeve and free end portions thereof extending toward the retaining member; an outer diameter of a ring formed by the free end portions of claw bodies is larger than an outer diameter of the drill bit. 13 20 25 26 37 57 04 N ov 2 02 5 2 0 2 5 2 6 3 7 5 7 0 4 N o v 2 0 2 5 d i a m e t e r o f t h e d r i l l b i t . 1 3

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of anchor rods, and particularly to a suspended self-drilling anchor rod device. BACKGROUND

[0002] Existing self-drilling anchor rods for mine tunnel support only have a one-time drilling function, and cannot immediately generate pre-tightening forces to suppress the early deformation of the surrounding rocks after drilling; and when drilling towards tops of mine tunnels, there is no suspension effect, and after drilling, anchor rods may fall off the drilling rig and injure people. SUMMARY

[0003] Embodiments of the present application disclose a suspended self-drilling anchor rod device, which can suppress early deformation of broken surrounding rocks and ensure construction safety.

[0004] Embodiments of the present application disclose a suspended self-drilling anchor rod device, comprising an anchor rod, a drill bit, a retaining member, and a reverse clamping claw, wherein the drill bit is disposed at an end portion of the anchor rod; the retaining member is fixed to the anchor rod and is used to restrict movement of the reverse clamping claw away from the drill bit; the reverse clamping claw is located between the retaining member and the drill bit and comprises a sleeve and claw bodies; the sleeve is sleeved on the anchor rod and spaced apart from the anchor rod; the claw bodies are arranged around the sleeve, the claw bodies comprise connecting end portions and free end portions opposite mutually; the connecting end portions are fixedly connected to the sleeve, and the free end portions extend toward the retaining member; distances between the claw bodies and a central axis of the anchor rod gradually increase along a direction from the drill bit to the retaining member; and an outer diameter of a ring formed by the free end portions of the of claw bodies is greater than an outer diameter of the drill bit.

[0005] Further, from the connecting end portions to the free end portions, size of the claw bodies in a circumferential direction of the anchor rod gradually increases.

[0006] Further, the free end portions are provided with abutment portions, and the abutment portions are used to abut against walls of a drill hole; and the abutment portions are in shapes of inverted trapezoids or inverted triangles.

[0007] Further, the connecting end portions are connected to an end portion of the sleeve adjacent to the retaining member.

[0008] Further, the sleeve is provided with notches, the notches are located between adjacent 2025263757   04 Nov 2025 claw bodies, and the notches are arc-shaped and smoothly transition with the claw bodies.

[0009] Further, the claw bodies are integrally formed with the sleeve.

[0010] Further, the retaining member is annular and is sleeved outside the anchor rod.

[0011] Further, an outer diameter of the retaining member is greater than an inner diameter of the sleeve.

[0012] Further, a chamfer is provided on an outer periphery of an end portion of the retaining member adjacent to the reverse clamping claw.

[0013] The suspended self-drilling anchor rod device further comprises an expansion shell, wherein the expansion shell is located between the drill bit and the reverse clamping claw, and the reverse clamping claw is able to abut against the expansion shell to restrict the expansion shell from moving in a direction away from the drill bit; and the expansion shell comprises expansion arms arranged around the anchor, when the drill bit moves into the expansion arms, the expansion arms are expanded by the drill bit and abut against walls of a drill hole.

[0014] Further, the expansion shell further comprises an elastic ring and connecting members, wherein the connecting members are arranged around the anchor rod and are separately provided, and the connecting members are connected to the expansion arms; and the elastic ring is sleeved on annular out sides of the connecting members.

[0015] Further, when the drill bit is separated from the expansion shell, adjacent connecting members abut against each other.

[0016] Further, limiting grooves are provided on outer sides of the connecting members, the limiting grooves are in shapes of elongated strips extending along circumference of the anchor rod, and the elastic ring is confined in the limiting grooves.

[0017] Further, barbs are provided on sides of the expansion arms facing away from the anchor rod, and the barbs on same expansion arms are arranged along an axial direction of the anchor rod.

[0018] Further, on the same expansion arms, tip portions of the barbs are aligned in the axial direction of the anchor rod.

[0019] Further, the expansion arms are fixed to end portions of the connecting members adjacent to the drill bit.

[0020] Further, the expansion arms and the connecting members correspond mutually and are integrally formed.

[0021] Further, the expansion arms comprise inclined surfaces facing the anchor rod, and distances between the inclined surfaces and the anchor rod gradually decrease along a direction from the drill bit to the retaining member.

[0022] Further, an outer peripheral surface of the drill bit comprises a tapered surface, and along 2 2025263757   04 Nov 2025 the direction from the drill bit to the retaining member, a distance between the tapered surface and the anchor rod gradually decreases.

[0023] Further, the tapered surface is provided with a groove, the drill bit is further provided with a connecting hole, the anchor rod is in a shape of a hollow rod, and the connecting hole connects the groove with an inner cavity of the anchor rod.

[0024] By implementing the embodiments of the present application, the anchor rod drives the drill bit to rotate to form a rock hole. During the drilling process of the drill bit, the retaining member can push the reverse clamping claw into the rock hole, and the claw bodies can abut against walls of the rock hole, thereby generating pre-tightening forces on walls of the rock hole to form reverse pressures, thereby suppressing the early deformation of broken surrounding rocks; at the same time, the present application can prevent the drill bit from falling out of the rock hole when drilling stops, so that head portions of the suspended self-drilling anchor rod device can be positioned in the rock hole to avoid falling and injuring construction workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] To more clearly illustrate technical solutions in the embodiments of the present application, the following briefly describes the accompanying drawings required for use in the embodiments.

[0026] Fig. 1 is a schematic structural diagram of a suspended self-drilling anchor rod device according to a preferred embodiment of the present application.

[0027] Fig. 2 is a schematic structural diagram of the suspended self-drilling anchor rod device in Fig. 1 from another angle.

[0028] Fig. 3 is an axial cross-sectional view of the suspended self-drilling anchor rod device in Fig. 1.

[0029] Fig. 4 is a schematic structural diagram of a reverse clamping claw in the suspended selfdrilling anchor rod device in Fig. 1.

[0030] Fig. 5 is a schematic structural diagram of the reverse clamping claw in Fig. 4 from another angle.

[0031] Fig. 6 is a schematic structural diagram of an expansion shell in the suspended selfdrilling anchor rod device in Fig. 1.

[0032] Fig. 7 is a schematic structural diagram of the expansion shell in Fig. 6 from another angle.

[0033] Fig. 8 is a schematic diagram of an exploded structure of the expansion shell in Fig. 6. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The following provides a clear and detailed description of the technical solutions in the embodiments of the present application, with reference to the accompanying drawings. 3 2025263757   04 Nov 2025

[0035] In the present application, unless otherwise specified or limited, terms such as "disposed," "connected," "connect," and "fixed" should be interpreted broadly. For example, they may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in the present application based on specific circumstances.

[0036] Please refer to Figs. 1, 2 and 3, a preferred embodiment of the present application provides a suspended self-drilling anchor rod device, comprising an anchor rod 1, a drill bit 2, a retaining member 3, a reverse clamping claw 4 and an expansion shell 5. The drill bit 2 is provided at an end portion of the anchor rod 1 for drilling, and the other end portion of the anchor rod 1 is used to be connected to a drilling rig to drive the drill bit 2 to rotate for drilling, thereby forming a rock hole at the top of the mine. The drill bit 2, the expansion shell 5, the reverse clamping claw 4 and the retaining member 3 are arranged in sequence along an axial direction of the anchor rod 1. The expansion shell 5 and the reverse clamping claw 4 are clearance-matched with the anchor rod 1 so that the two can move relative to the anchor rod 1 to avoid rotation driven by the anchor rod 1; and the retaining member 3 is fixed to the anchor rod 1 to limit the expansion shell 5 and the reverse clamping claw 4 between the retaining member 3 and the drill bit 2.

[0037] The reverse clamping claw 4 is located between the retaining member 3 and the drill bit 2. The retaining member 3 can limit the reverse clamping claw 4 from moving in a direction away from the drill bit 2 to prevent it from moving up and down on the anchor rod 1 during drilling, ensuring that the reverse clamping claw 4 enters the rock hole.

[0038] As shown in Figs. 3, 4, and 5, the reverse clamping claw 4 comprises a sleeve 41 and claw bodies 42. The sleeve 41 is sleeved onto the anchor rod 1 and is spaced apart from the anchor rod 1 so that the reverse clamping claw 4 does not rotate with the anchor rod 1. The claw bodies 42 are arranged around the sleeve 41 and are used to abut against walls of the rock hole. Together with the retaining member 3, they can prevent the suspended self-drilling anchor rod 1 device from falling out of the rock hole. The claw bodies 42 comprise corresponding connecting end portions 421 and free end portions 422. The connecting end portions 421 are fixedly connected to the sleeve 41, and the free end portions 422 extend toward the retaining member 3, forming a reverse structure in which the claw bodies 42 extend in an opposite direction of drilling. Along a direction from the drill bit 2 to the retaining member 3, distances between the bodies 42 and a central axis of the anchor rod 1 gradually increase; an outer diameter of a ring surrounded by the free end portions 422 of the claw bodies 42 is larger than an outer diameter of the drill bit 2, and an outer 2025263757   04 Nov 2025 diameter of the drill bit 2 is an aperture of the rock hole. This structure allows the reverse clamping claw 4 to enter the rock hole, and the claw bodies 42 can all abut against the rock hole.

[0039] The anchor rod 1 drives the drill bit 2 to rotate to form a rock hole. During the drilling process of the drill bit 2, the retaining member 3 can push the reverse clamping claw 4 into the rock hole, and the claw bodies 42 can abut against walls of the rock hole, thereby generating a pretightening force on walls of the rock hole to form a reverse pressure, thereby inhibiting the early deformation of broken surrounding rocks; at the same time, it can prevent the drill bit 2 and the expansion shell 5 from falling out of the rock hole when drilling is stopped, so that head portions of the suspended self-drilling anchor rod 1 device can be positioned in the rock hole to avoid falling and injuring construction workers.

[0040] From the connecting end portions 421 to the free end portions 422, size of the claw bodies 42 in a circumferential direction of the anchor rod 1 gradually increases, so that the structural strength of the claw bodies 42 near the free end portions 422 is greater, so as to effectively abut against walls of the rock hole. The abutment portions 423 are in shapes of inverted trapezoids or inverted triangles, so that end portions of the abutment portions 423 facing walls of the rock hole are pointed and can penetrate into walls of the rock hole, thereby ensuring the abutting strength between the abutment portions 423 and walls of the rock hole and preventing it from falling out of the rock hole.

[0041] In the present embodiment, the connecting end portions 421 are connected to the end portions of the sleeve 41 adjacent to the retaining member 3. This facilitates the processing and preparation of the reverse clamping claw 4 and helps the sleeve 41 apply force to the claw bodies 42 toward the retaining member 3. The sleeve 41 is provided with notches 411, located between adjacent claw bodies 42. The notches 411 are arc-shaped and smoothly transition with the claw bodies 42. The notches 411 allow for smooth transitions between the sleeve 41 and the claw bodies 42, improving the connection strength and preventing fracture at the joint. The claw bodies 42 are integrally formed with the sleeve 41, enhancing the connection strength between the claw bodies 42 and the sleeve 41.

[0042] Preferably, the reverse clamping claw 4 can be formed by stamping the sleeve 41 and the claw bodies 42 from sheet metal, which is then rolled into a ring-shaped structure. The connecting end portions 421 of the claw bodies 42 are bent outward to form the reverse clamping claw 4. This method facilitates the processing and manufacture of the reverse clamping claw 4 and ensures that the thickness of the sleeve 41 and the claw bodies 42 are consistent.

[0043] Moreover, in other embodiments, the connecting end portions 421 of the claw bodies 42 can also be connected to the outer wall of the sleeve 41, and the two can be connected by welding 5 2025263757   04 Nov 2025 or other means.

[0044] As shown in Figs. 2 and 3, the retaining member 3 is annular and is sleeved outside the anchor rod 1 to facilitate the assembly and connection of the two, improve the connection strength, do not damage the structure of the anchor rod 1, and facilitate the application of force to the reverse clamping claw 4. Of course, in other embodiments, the retaining member 3 can also be a pin that is inserted into the anchor rod 1 along a radial direction of the anchor rod 1.

[0045] An outer diameter of the retaining member 3 is larger than an inner diameter of the sleeve 41, allowing it to apply force to the claw bodies 42, causing them to expand and better abut against the rock hole. A chamfer 31 is provided on an outer periphery of an end portion of the retaining member 3 adjacent to the reverse clamping claw 4. The chamfer 31 allows for smoother application of the force to the reverse clamping claw 4, thereby increasing a diameter of a ring formed by the free end portions 422.

[0046] The expansion shell 5 is located between the drill bit 2 and the reverse clamping claw 4. The reverse clamping claw 4 abuts against the expansion shell 5 to limit its movement away from the drill bit 2, effectively preventing it from falling.

[0047] As shown in Figs. 6, 7, and 8, in the present embodiment, the expansion shell 5 comprises expansion arms 51 arranged around the anchor rod 1. When the drill bit 2 moves into the expansion arms 51, the expansion arms 51 are expanded by the drill bit 2 and abut against walls of the rock hole. The drill bit 2 can expand the expansion arms 51 so that all of them abut against walls of the rock hole.

[0048] When the suspended self-drilling anchor bolt 1 reaches a designed depth and is disconnected from the drill rig, the drill bit 2 and anchor bolt 1 fall due to their own weight. At this point, the reverse clamping claw 4 engages walls of the rock hole and stops the falling expansion shell 5. As the drill bit 2 continues to fall, the expansion arms 51 of the expansion shell 5 are expanded by the drill bit 2 under the opposing forces of the reverse clamping claw 4 and the drill bit 2, pressing against walls of the rock hole to generate surrounding rock preload. The expansion shell 5 and reverse clamping claw 4 simultaneously secure the anchor bolt 1, preventing it from falling.

[0049] As shown in Figs. 6, 7, and 8, the expansion shell 5 further comprises an elastic ring 52 and connecting members 53. The connecting members 53 are arranged around the anchor rod 1 and are separately arranged. The connecting members 53 are connected to expansion arms 51. The elastic ring 52 is mounted annual outer sides of the connecting members 53. When the drill bit 2 is outside the expansion shell 5, the connecting members 53 and the expansion arms 51 are positioned relatively close to the anchor rod 1 under an action of the elastic ring 52. That is, a 6 2025263757   04 Nov 2025 diameter of the ring formed by the connecting members 53 and the expansion arms 51 is relatively small. When the drill bit 2 moves into the expansion shell 5, the connecting members 53 and the expansion arms 51 overcome an elastic force of the elastic ring 52 and move relatively far away from the anchor rod 1. That is, the diameter of the ring formed by the connecting members 53 and the expansion arms 51 increases, thereby causing the expansion arms 51 to abut against walls of the rock hole, preventing the expansion shell 5 from moving relative to the rock hole and positioning the expansion shell 5 within the rock hole.

[0050] Since the connecting members 53 are arranged separately, as the drill bit 2 moves axially along the anchor rod 1, the connecting members 53, along with their corresponding expansion arms 51, can move radially along the anchor rod 1, which allows the entire outer surface of the expansion arms 51 to contact walls of the rock hole, increasing the interaction between them and more reliably positioning the expansion shell 5 and drill bit 2 in the rock hole.

[0051] When the drill bit 2 and expansion shell 5 are separated, adjacent connecting members 53 abut against each other, allowing the elastic ring 52 to position the ring formed by the connecting members 53 at a fixed diameter. This ensures that both the connecting members 53 and the expansion arms 51 are spaced apart from the anchor rod 1, preventing the expansion shell 5 from rotating under the influence of the anchor rod 1.

[0052] Limiting grooves 530 are provided outside the connecting members 53. The limiting grooves 530 are elongated strips extending along the circumference of the anchor rod 1. The elastic ring 52 is limited in the limiting grooves 530. The limiting grooves 530 facilitate the positioning and connection between the connecting members 53 and the elastic ring 52, preventing the elastic ring 52 from shifting and affecting the elastic force on the connecting members 53. The elastic ring 52 can be a rubber ring or a spring ring, and can provide a force to the connecting members 53 toward the anchor rod 1.

[0053] The expansion arms 51 are equipped with barbs 511 on the side facing away from the anchor rod 1. The barbs 511 on same expansion arms 51 are arranged axially along the anchor rod 1. The barbs 511 increase friction between the expansion arms 51 and walls of the rock hole, ensuring close contact and preventing movement between the expansion shell 5 and walls of the rock hole

[0054] The tip portions of the barbs 511 on the same expansion arm 51 are aligned axially along the anchor rod 1, ensuring that the barbs 511 contacts walls of the rock hole. Here, top portions of the barbs 511 refer to tip portions of the barbs 511 facing away from the anchor rod 1.

[0055] The expansion arms 51 are fixed to end portions of the connecting members 53 adjacent to the drill bit 2, allowing the drill bit 2 to directly act on the expansion arms 51, effectively 2025263757   04 Nov 2025 contacting walls of the rock hole. The expansion arms 51 and corresponding connecting members 53 are integrally formed to enhance connection strength.

[0056] As shown in Fig. 3, sides of the expansion arms 51 facing the anchor rod 1 are formed with inclined surfaces 512. The distances between the inclined surface 512 and the anchor rods 1 gradually decrease as the drill bit 2 moves axially relative to the expansion arms 51, which allows the expansion arms 51 to gradually move away from the anchor rod 1 and toward walls of the rock hole.

[0057] As shown in Figs. 1 and 3, the outer circumference of the drill bit 2 comprises a tapered surface 21. The distance between the tapered surface 21 and the anchor rod 1 gradually decreases as the drill bit 2 approaches the retaining member 3. The tapered surface 21, in conjunction with the inclined surface 512, facilitates the application of force by the drill bit 2 toward the expansion arm 51, ensuring smooth movement of the expansion arms 51 and their connecting members 53.

[0058]

[0059] A groove 22 is provided on the tapered surface 21, and a connecting hole 23 is also provided on the drill bit 2. The anchor rod 1 is hollow, and the connecting hole 23 connects the groove 22 with an inner cavity of the anchor rod 1.

[0060] The groove 22 creates gaps between groove walls and the inclined surfaces 512 of the expansion arms 51, facilitating the injection of concrete or glue from the inner cavity of the anchor rod 1 through the connecting hole 23 and the groove 22, ensuring that the drill bit 2 is securely and reliably positioned within walls of the rock hole.

[0061] The suspended self-drilling anchor rod 1 device provided by the present application truly realizes the three-in-one anchor rod functions of one-time drilling, immediate provision of pretightening force, and suspension and anti-falling by arranging a retaining member 3, a reverse clamping claw 4 and an expansion shell 5, which greatly reduces the anchor rod construction process underground in mines and tunnels, saves construction working time, and at the same time achieves the suspension and fixation of the anchor rod to prevent injuries; the present application realizes that one drilling rig can complete all the processes of drilling anchor holes, installing anchor rods, and fixing anchor rods at one time and achieve the designed function; since the expansion shell 5 and the reverse clamping claw 4 are subjected to force at the same time, the product of the present application is suitable for use in different geological conditions of hard rock and soft rock.

[0062] In summary, although the present application has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present application. A person skilled in the art may make various changes and modifications without 8 2025263757   04 Nov 2025 departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be based on the scope defined in the claims.

Claims

1. A suspended self-drilling anchor rod device, comprising an anchor rod, a drill bit, a retaining member, and a reverse clamping claw,wherein the drill bit is disposed at an end portion of the anchor rod;the retaining member is fixed to the anchor rod and is used to restrict movement of the reverse clamping claw away from the drill bit;the reverse clamping claw is located between the retaining member and the drill bit and comprises a sleeve and claw bodies;the sleeve is sleeved on the anchor rod and spaced apart from the anchor rod;the claw bodies are arranged around the sleeve, the claw bodies comprise mutually opposite connecting end portions and free end portions;the connecting end portions are fixedly connected to the sleeve, and the free end portions extend toward the retaining member;distances between the claw bodies and a central axis of the anchor rod gradually increase along a direction from the drill bit to the retaining member; andan outer diameter of a ring formed by free end portions of the claw bodies is greater than an outer diameter of the drill bit.

2. The suspended self-drilling anchor rod device according to claim 1, wherein a size of the claw bodies in a circumferential direction of the anchor rod gradually increases from the connecting end portions to the free end portions.

3. The suspended self-drilling anchor rod device according to claim 2, wherein the free end portions are provided with abutment portions and the abutment portions are used to abut against walls of a drill hole; andthe abutment portions are in shapes of inverted trapezoids or inverted triangles.

4. The suspended self-drilling anchor rod device according to claim 1, wherein the connecting end portions are connected to an end portion of the sleeve adjacent to the retaining member.

5. The suspended self-drilling anchor rod device according to claim 4, wherein the sleeve is provided with notches, the notches are located between adjacent claw bodies, and the notches are2025263757   04 Nov 2025arc-shaped and smoothly transition with the claw bodies.

6. The suspended self-drilling anchor rod device according to claim 5, wherein the claw bodies are integrally formed with the sleeve.

7. The suspended self-drilling anchor rod device according to claim 1, wherein the retaining member is annular and is sleeved outside the anchor rod.

8. The suspended self-drilling anchor rod device according to claim 7, wherein an outer diameter of the retaining member is greater than an inner diameter of the sleeve.

9. The suspended self-drilling anchor rod device according to claim 8, wherein a chamfer is provided on an outer periphery of an end portion of the retaining member adjacent to the reverse clamping claw.

10. The suspended self-drilling anchor rod device according to claim 1, further comprising an expansion shell,wherein the expansion shell is located between the drill bit and the reverse clamping claw, the reverse clamping claw is able to abut against the expansion shell to restrict the expansion shell from moving in a direction away from the drill bit; andthe expansion shell comprises expansion arms arranged around the anchor rod, and when the drill bit moves into the expansion arms, the expansion arms are expanded by the drill bit and abut against walls of a drill hole.

11. The suspended self-drilling anchor rod device according to claim 10, wherein the expansion shell further comprises an elastic ring and connecting members, the connecting members are arranged around the anchor rod and are separately provided, and the connecting members are connected to the expansion arms; andthe elastic ring is sleeved on annular out sides of the connecting members.

12. The suspended self-drilling anchor rod device according to claim 11, wherein when the drill bit is separated from the expansion shell, adjacent connecting members abut against each other.2025263757   04 Nov 202513. The suspended self-drilling anchor rod device according to claim 11, wherein limiting grooves are provided on outer sides of the connecting members, the limiting grooves are in shapes of elongated strips extending along circumference of the anchor rod, and the elastic ring is confined in the limiting grooves.

14. The suspended self-drilling anchor rod device according to claim 11, wherein barbs are provided on sides of the expansion arms facing away from the anchor rod, and the barbs on same expansion arms are arranged along an axial direction of the anchor rod.

15. The suspended self-drilling anchor rod device according to claim 14, wherein on the same expansion arms, tip portions of the barbs are aligned in the axial direction of the anchor rod.

16. The suspended self-drilling anchor rod device according to claim 11, wherein the expansion arms are fixed to end portions of the connecting members adjacent to the drill bit.

17. The suspended self-drilling anchor rod device according to claim 16, wherein the expansion arms and the connecting members correspond mutually and are integrally formed.

18. The suspended self-drilling anchor rod device according to claim 10, wherein the expansion arms comprise inclined surfaces facing the anchor rod, and distances between the inclined surfaces and the anchor rod gradually decrease along a direction from the drill bit to the retaining member.

19. The suspended self-drilling anchor rod device according to claim 18, wherein an outer peripheral surface of the drill bit comprises a tapered surface, and along the direction from the drill bit to the retaining member, a distance between the tapered surface and the anchor rod gradually decreases.

20. The suspended self-drilling anchor rod device according to claim 19, wherein the tapered surface is provided with a groove, the drill bit is further provided with a connecting hole, the anchor rod is in a shape of a hollow rod, and the connecting hole connects the groove with an inner cavity of the anchor rod.

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