Rear underreamed anchor bolt

Abstract

The utility model provides a rear underreamed anchor bolt, and belongs to the technical field of fastening by inserting pins or other devices fastened in walls or similar pieces into wall holes manufactured for the rear underreamed anchor bolt. The rear underreaming anchor bolt comprises an anchor rod, a sleeve and a first locking key, the anchor rod is sleeved with the sleeve, the first locking key comprises a plurality of first key pieces, the end of the anchor rod is provided with a conical head used for allowing the first key pieces to be opened outwards when the anchor rod and the first locking key generate axial relative movement, the anchor rod is a hollow anchor rod, and a glue injection channel extending in the axial direction is formed in the anchor rod. The wall of the anchor rod is provided with a glue injection hole which is communicated with the glue injection channel and penetrates through the wall of the anchor rod so that glue can flow into the mounting hole of the base body. On the basis that mechanical friction anchoring is achieved between the first key piece and the base body installation hole, the anchoring effect is further enhanced through anchoring force generated between the solidified glue and the base body installation hole, it is guaranteed that the anchoring effect is lasting and effective, and the problem that an anchor bolt is prone to disengaging from a base body in special application scenes is solved.

Description

Technical Field

[0001] This utility model relates to a rear-expanded bottom anchor bolt, belonging to the field of pins or other devices fastened in walls or similar parts, and fastened by inserting them into a wall hole made for this purpose. Background Technology

[0002] Post-expansion anchors are manufactured by first drilling holes in a concrete or wooden substrate, then inserting the anchor, which opens the locking key on the expansion sleeve and locks it against the hole wall, achieving a post-anchoring connection between the anchor and the substrate. Traditional post-expansion anchors typically use a single-key expansion sleeve with a locking key only at one end. For example, Chinese utility model patent CN214533905U discloses a post-expansion anchor that includes a screw and a sleeve fitted onto the screw. One end of the sleeve has a locking key composed of multiple key plates, and one end of the screw has an expansion head. During use, the relative movement between the sleeve and the screw causes the locking key to open along the expansion head, forming a ring of anchor points with the hole wall. Due to the limited number of anchor points, the anchoring effect of this type of anchor is limited.

[0003] Chinese utility model patent CN204025271U discloses a novel multi-key expansion anchor bolt. The anchor bolt includes an anchor rod with a tapered head at its end. From top to bottom, the anchor rod is fitted with a nut, a sleeve, a first anchor bolt sleeve (i.e., a double-key sleeve), and a second anchor bolt sleeve (i.e., a single-key sleeve). The first anchor bolt sleeve has a first expansion portion (i.e., a locking key) at its upper and lower ends, and the second anchor bolt sleeve has a second expansion portion (i.e., a locking key) at its lower end. During installation, pressing down on the sleeve causes the second expansion portion of the second anchor bolt sleeve to open outwards along the tapered head at the lower end of the anchor rod, forming a first ring of anchor points with the hole wall. The first expansion portion at the upper end of the first anchor bolt sleeve opens outwards along the tapered surface at the lower end of the sleeve, forming a second ring of anchor points with the hole wall. The first expansion portion at the lower end of the first anchor bolt sleeve opens outwards along the tapered surface at the upper end of the second anchor bolt sleeve, forming a third ring of anchor points with the hole wall. The anchor bolt forms multiple anchoring points with the borehole wall, improving the anchoring effect.

[0004] However, regardless of the number of anchor points, in some special application scenarios, such as environments with vibration and impact, anchor bolts are prone to loosening. In other cases, in environments with high humidity and chemical corrosion, the anchor bolts themselves are made of metal and are easily corroded. In these situations, if the anchor bolts rely solely on the mechanical friction between the locking key and the mounting hole in the base, it is difficult to ensure that the anchoring effect is effective for a long time, which will eventually lead to the anchor bolts coming off the base. Utility Model Content

[0005] The purpose of this utility model is to provide a rear-expanded bottom anchor bolt to solve the problem that existing rear-expanded bottom anchor bolts rely solely on mechanical friction between the locking key and the mounting hole in the base to ensure anchoring effect, which leads to the anchor bolt easily coming out of the base in special application scenarios.

[0006] To achieve the above objectives, the rear-expanded bottom anchor bolt of this utility model adopts the following technical solution:

[0007] A rear-expanded bottom anchor bolt includes an anchor rod, a sleeve fitted outside the anchor rod, and a first locking key. The first locking key is integrally connected to the sleeve or separately set. The first locking key includes multiple first key pieces. The end of the anchor rod is provided with a conical head for cooperating with each of the first key pieces to allow the first key pieces to open outward when the anchor rod and the first locking key generate axial relative movement. The anchor rod is a hollow anchor rod. The anchor rod has an axially extending glue injection channel for injecting glue from the outside of the substrate. The wall of the anchor rod has a glue injection hole that communicates with the glue injection channel and penetrates the wall of the anchor rod to allow glue to flow into the mounting hole in the substrate.

[0008] The beneficial effects of the above technical solution are as follows: This utility model is an improved invention. The improvement lies in that the anchor rod is a hollow anchor rod with an axially extending glue injection channel inside. Glue can be injected into the glue injection channel from the outside of the substrate. At the same time, the wall of the anchor rod has a glue injection hole that communicates with the glue injection channel and penetrates the wall of the anchor rod. In this way, the glue in the glue injection channel can flow into the substrate mounting hole through the glue injection hole, filling the space inside the substrate mounting hole. Thus, based on the mechanical friction anchoring between the first key piece and the substrate mounting hole, the anchoring effect is further strengthened by the anchoring force generated between the glue after curing and the substrate mounting hole. This enhances the anti-loosening effect of the anchor bolt in vibration and impact environments. At the same time, the glue is not easily affected by high humidity and chemical corrosion environments, and can completely seal the part of the anchor bolt located in the substrate mounting hole, ensuring a long-lasting and effective anchoring effect and solving the problem that the anchor bolt is prone to detaching from the substrate in special application scenarios.

[0009] Furthermore, the injection hole includes a first injection hole arranged corresponding to the position of the first key piece.

[0010] Furthermore, the rear-expanded bottom anchor bolt includes a single-key sleeve that is separately disposed from the sleeve, and a first locking key is integrally connected to the single-key sleeve. The rear-expanded bottom anchor bolt also includes a double-key sleeve, and a second locking key is provided at each end of the double-key sleeve. The second locking key includes multiple second key pieces, and the glue injection hole also includes a second glue injection hole arranged corresponding to the positions of the second key pieces at both ends.

[0011] Furthermore, the injection hole also includes a third injection hole arranged corresponding to the middle position of the double bond sleeve.

[0012] Furthermore, the first injection hole, two second injection holes, and the third injection hole are arranged at equal intervals along the axial direction of the anchor rod.

[0013] Furthermore, both the second and third injection holes are radially penetrating "I"-shaped holes that run through the anchor rod.

[0014] Furthermore, the penetration direction of the third injection hole is perpendicular to the penetration direction of the second injection holes on both sides.

[0015] Furthermore, the first injection hole is a cross-shaped hole that penetrates the anchor rod in a radial direction perpendicular to each other.

[0016] Furthermore, the adhesive injection channel extends axially through the anchor bolt.

[0017] Furthermore, the portion of the glue injection channel located inside the conical head is funnel-shaped. Attached Figure Description

[0018] Figure 1 This is an assembly drawing (before anchoring) of an embodiment of the rear-expanded bottom anchor of this utility model.

[0019] Figure 2 This is an exploded view of an embodiment of the rear-expanded bottom anchor bolt of this utility model;

[0020] Figure 3 This is an assembly drawing (after anchoring) of an embodiment of the rear-expanded bottom anchor bolt of this utility model.

[0021] Figure 4 for Figure 3 Enlarged view of point A in the middle.

[0022] In the diagram: 1. Anchor bolt; 1-1. Smooth bolt section; 1-1-1. Conical head; 1-2. Screw section; 1-3. Glue injection channel; 1-4. First glue injection hole; 1-5. Second glue injection hole; 1-6. Third glue injection hole; 2. Nut; 3. Spring washer; 4. Flat washer; 5. Sleeve; 6. Double key sleeve; 6-1. Second locking key; 7. Single key sleeve; 7-1. First locking key; 7-1-1. Teeth. Detailed Implementation

[0023] To address the technical problems existing in the prior art, the basic concept of this utility model is to set an adhesive injection channel inside the anchor rod and an adhesive injection hole on the wall of the anchor rod, so that the adhesive flows into the mounting hole of the base body through the adhesive injection channel and the adhesive injection hole, and the anchoring effect is further enhanced by the anchoring force generated between the adhesive and the mounting hole of the base body after the adhesive cures.

[0024] The features and performance of this utility model will be further described in detail below with reference to the embodiments.

[0025] Example 1 of the rear-expanded bottom anchor bolt of this utility model:

[0026] like Figure 1 , Figure 2 and Figure 3 As shown, the rear-expanded bottom anchor bolt includes an anchor rod 1, on which a nut 2, a spring washer 3, a flat washer 4, a sleeve 5, a double-key sleeve 6, and a single-key sleeve 7 are sequentially fitted from top to bottom.

[0027] The anchor rod 1 includes a lower smooth rod section 1-1 and an upper screw section 1-2. The lower end of the smooth rod section 1-1 is provided with a conical head 1-1-1, with the larger end of the conical head 1-1-1 facing downwards and the smaller end connected to the main body of the smooth rod section 1-1. The lower part of the single-key sleeve 7 is integrally connected with a first locking key 7-1, which includes multiple circumferentially arranged first key pieces (four in this embodiment). The connection between the first key pieces and the single-key sleeve 7 is provided with a groove to facilitate the folding of the first key pieces. When the anchor rod 1 and the first locking key 7-1 move axially relative to each other, the conical head 1-1-1 cooperates with each of the first key pieces, causing the first key pieces to open outwards along the outer surface of the conical head 1-1-1, thereby locking into the mounting hole of the base body and achieving mechanical friction anchoring with the mounting hole of the base body.

[0028] Furthermore, such as Figure 3 and Figure 4 As shown, each first key piece is provided with two tapered teeth 7-1-1. When the tapered head 1-1-1 drives each first key piece to expand outward, the teeth 7-1-1 on the first key piece can be locked into the hole wall of the mounting hole of the base, making the connection of the anchor point more reliable and less likely to come off.

[0029] like Figure 1 and Figure 2 As shown, the single-key sleeve 7 has a cylindrical structure in the middle and a frustum-shaped structure at the top, making the outer circumferential surface of the upper part conical. The double-key sleeve 6 has a cylindrical structure in the middle, with second locking keys 6-1 connected to the upper and lower ends respectively. Each second locking key 6-1 includes multiple circumferentially arranged second key plates (four in this embodiment). The connection between the second key plates and the double-key sleeve 6 is provided with a groove to facilitate the folding of the second key plates. The diameter of the small end of the upper part of the single-key sleeve 7 is smaller than the inner diameter of the second locking key 6-1 when it is not expanded, so the upper end of the single-key sleeve 7 can be inserted into the unexpanded second locking key 6-1 below.

[0030] The lower part of sleeve 5 has a frustum-shaped structure, making its lower outer circumferential surface conical. The rest of the main body of sleeve 5 has a cylindrical structure. The diameter of the small end of the lower part of sleeve 5 is smaller than the inner diameter of the second locking key 6-1 when it is not expanded. Therefore, the lower end of sleeve 5 can be inserted into the upper unexpanded second locking key 6-1. When sleeve 5 and anchor rod 1 move axially relative to each other, sleeve 5 compresses double-key sleeve 6, and double-key sleeve 6 compresses single-key sleeve 7, causing it to move downward relative to anchor rod 1. This causes the first locking key 7-1 to open outward under the action of the conical head 1-1-1, the lower second locking key 6-1 to open outward under the action of the upper outer conical surface of the single-key sleeve 7, and the upper second locking key 6-1 to open outward under the action of the lower outer conical surface of sleeve 5. Figure 3 As shown, this achieves anchoring between the three-ring locking key and the mounting hole in the base.

[0031] In addition, the anchor rod 1 in this utility model is a hollow anchor rod, such as... Figure 2 As shown, the anchor rod 1 has an axially extending glue injection channel 1-3 for injecting glue from the outside of the substrate. The glue injection channel 1-3 extends axially through the anchor rod 1, and the port of the glue injection channel 1-3 located at the end face of the screw section 1-2 constitutes a glue injection port, thereby facilitating the injection of glue into the glue injection channel 1-3. The portion of the glue injection channel 1-3 located inside the conical head 1-1-1 is funnel-shaped, which makes the wall thickness of the anchor rod 1 uniform, and at the same time facilitates the flow of glue from the port at the end of the glue injection channel 1-3 into the mounting hole of the substrate.

[0032] The wall of anchor rod 1 is provided with an injection hole that communicates with and penetrates the wall of anchor rod 1 to allow adhesive to flow into the mounting hole of the substrate. This allows the adhesive to fill the space inside the mounting hole of the substrate. Based on the mechanical friction anchoring of the first and second key plates with the mounting hole of the substrate, the anchoring effect is further enhanced by the anchoring force generated between the adhesive and the mounting hole of the substrate after the adhesive has cured. This enhances the anti-loosening effect of the anchor bolt in vibration and impact environments. At the same time, the adhesive is not easily affected by high humidity and chemical corrosion environments, and can completely wrap and seal the part of the anchor bolt located in the mounting hole of the substrate, ensuring a long-lasting and effective anchoring effect and solving the problem that the anchor bolt is easy to detach from the substrate in special application scenarios.

[0033] Specifically, the glue injection holes include a first glue injection hole 1-4 corresponding to the position of the first key piece, a second glue injection hole 1-5 corresponding to the positions of the second key pieces at both ends, and a third glue injection hole 1-6 corresponding to the middle position of the double key sleeve 6. The first glue injection hole 1-4, the second glue injection hole 1-5, and the third glue injection hole 1-6 are all located on the smooth rod section 1-1, with the first glue injection hole 1-4 located on the conical head 1-1-1, and the upper second glue injection hole 1-5 located near the screw section 1-2. The four sets of glue injection holes—the first glue injection hole 1-4, the two second glue injection holes 1-5, and the third glue injection hole 1-6—are evenly spaced along the axial direction of the anchor rod 1 to ensure that the glue can be evenly filled into the base mounting hole.

[0034] Furthermore, the second injection hole 1-5 and the third injection hole 1-6 are both "I"-shaped holes that penetrate the anchor rod 1 radially, which is convenient for processing. Since they penetrate the anchor rod 1 radially, a single "I"-shaped hole will form two holes on the wall of the anchor rod 1.

[0035] Furthermore, the through direction of the third injection hole 1-6 is perpendicular to the through direction of the second injection holes 1-5 on both sides. That is, the openings of the third injection hole 1-6 and the adjacent second injection holes 1-5 are offset in the circumferential direction and arranged at a 90-degree angle. After the glue flows out from the openings of the second injection holes 1-5 and the third injection hole 1-6, it flows downward and fills the external space of the bare rod section 1-1, which helps the glue to fill the substrate mounting hole.

[0036] In addition, the first glue injection holes 1-4 are cross-shaped holes that penetrate the anchor rod 1 in a radial direction perpendicular to each other. The cross-shaped holes will form four holes on the wall of the anchor rod 1, which is conducive to filling the bottom part of the base mounting hole with glue, ensuring that the gap between the anchor bolt and the base mounting hole is completely covered by glue, avoiding the formation of air cavitation, and promoting the uniform distribution of glue at the bottom part of the hole.

[0037] During installation of the rear-expanded anchor bolt of this utility model, firstly, according to the specifications and model of the anchor bolt, a hole is drilled in the base using an impact drill to ensure that the diameter and depth of the hole meet the installation requirements of the anchor bolt. Then, the assembled anchor bolt is placed into the drilled straight hole (i.e., the base installation hole). At this time, the upper end face of the sleeve 5 of the anchor bolt is higher than the surface of the base. Then, the flat washer 4, the spring washer 3, and the nut 2 are removed from the screw section 1-2 of the anchor rod 1. The sleeve 5 is rotated using a special drill bit for the expanded anchor bolt, causing the sleeve 5 to move towards the bottom of the base installation hole. The sleeve 5 squeezes the double-key sleeve 6, and the double-key sleeve 6 squeezes the single-key sleeve 7, causing it to move downward relative to the anchor rod 1. Finally, the first locking key 7-1 opens outward under the action of the conical head 1-1-1. The first key plate fits tightly with the enlarged hole at the bottom of the hole, forming the first ring of anchor points; the lower second locking key 6-1 opens outward under the action of the outer conical surface of the upper part of the single key sleeve 7, so that the lower second key plate fits tightly with the mounting hole of the base body, forming the second ring of anchor points; the upper second locking key 6-1 opens outward under the action of the outer conical surface of the lower part of the sleeve 5, so that the upper second key plate fits tightly with the mounting hole of the base body, forming the third ring of anchor points. At this time, the end face of the sleeve 5 is flush with the surface of the base body, and the end of the screw section 1-2 extends out of the base body.

[0038] Then, the anchoring adhesive is injected into the injection channels 1-3 from the end of the anchor rod 1. For example, in the construction of photovoltaic power stations, anchoring adhesive is used for anchoring. During the injection process, the anchoring adhesive flows out along the opening at the end of the injection channels 1-3 and each injection hole until the entire substrate installation hole is filled. If the curing temperature is 25 degrees Celsius, the anchoring adhesive will cure after 3 days, and the anchoring force of the anchor bolt will be greater than the yield value of the steel bar, reaching the pull-out resistance requirement of 6kN.

[0039] After the glue has fully cured, thread the screw section 1-2 through the item to be fixed, and then put the flat washer 4, spring washer 3 and nut 2 on the screw section 1-2 of the anchor rod 1 in sequence, and tighten the nut 2 until the item is secured.

[0040] Example 2 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, when installing the anchor bolt, after the anchor bolt is placed in the mounting hole of the base and the flat washer, spring washer and nut have been removed, a force transmission tube can be used to cover the outside of the anchor rod. One end of the force transmission tube abuts against the sleeve, and the other end of the force transmission tube is struck with a hammer. The force transmission tube pushes the sleeve to move, which can also make the sleeve, double-key sleeve and single-key sleeve move relative to the anchor rod, so as to realize the opening and anchoring of each locking key. This is a manual installation.

[0041] Example 3 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, when installing the anchor bolt, after the anchor bolt is placed in the mounting hole of the base, the end face of the sleeve can be made flush with the end face of the base by controlling the size of the mounting hole of the base. Then, the flat washer, spring washer and nut are removed first, so that the screw section of the anchor rod passes through the fixing object. Then, the flat washer, spring washer and nut are installed in sequence, and then the nut is tightened. The nut presses the spring washer and rotates continuously. Under the principle of the screw nut mechanism, the anchor rod moves outward, realizing the axial relative movement between the anchor rod and the locking key. Similarly, it can control the opening of each locking key.

[0042] Example 4 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the part of the glue injection channel located inside the conical head is cylindrical, that is, the glue injection channel is a hole of equal diameter. At this time, the wall thickness of the conical head part is greater than the wall thickness of the rest of the anchor bolt.

[0043] Example 5 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the glue injection channel does not extend through the anchor rod axially. For example, the end of the conical head is closed. In this case, the glue can only flow into the base mounting hole through the glue injection hole.

[0044] Example 6 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the first glue injection hole arranged corresponding to the position of the first key piece is not a "+" shaped hole, but a "I" shaped hole.

[0045] Example 7 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the second glue injection hole arranged corresponding to the positions of the second key pieces at both ends and the third glue injection hole arranged corresponding to the middle position of the double key sleeve are both "+" shaped holes.

[0046] Example 8 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the first injection hole corresponding to the position of the first key piece, the second injection hole corresponding to the positions of the second key pieces at both ends, and the third injection hole corresponding to the middle position of the double key sleeve are all single-hole injection holes. The injection hole does not penetrate the entire anchor bolt radially, but only penetrates one wall of the anchor bolt, thus forming only one hole. At this time, different injection holes can be arranged at intervals along the same axial direction or staggered.

[0047] Example 9 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, when both the second and third injection holes are "I"-shaped holes, the penetration directions of the second and third injection holes are not perpendicular, but parallel.

[0048] Example 10 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the first injection hole, the two second injection holes and the third injection hole are not equally spaced in the axial direction of the anchor bolt, for example, the axial spacing gradually decreases or gradually increases.

[0049] Example 11 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the glue injection hole does not include the third glue injection hole arranged corresponding to the middle position of the double key sleeve, but only includes the first glue injection hole and the second glue injection hole.

[0050] Example 12 of the rear-expanded bottom anchor bolt of this utility model: Unlike Example 1, the rear-expanded bottom anchor bolt is a single-key anchor bolt, that is, the rear-expanded bottom anchor bolt does not include the double-key sleeve, but only includes the single-key sleeve. At this time, the first locking key can be integrally connected to the single-key sleeve. The single-key sleeve and the sleeve are separately set, that is, the first locking key and the sleeve are separately set. Of course, the first locking key can also be integrally connected to the sleeve. The sleeve and the first locking key together constitute the single-key sleeve. At this time, only the first key plate cooperates with the tapered head at the end of the anchor rod to achieve anchoring, that is, there is only one ring of anchoring points. In addition, there can still be multiple sets of glue injection holes. Multiple sets of glue injection holes are arranged at equal or non-equal intervals along the axial direction of the anchor rod. Of course, the glue injection holes can also only include the first glue injection hole, without the second and third glue injection holes, and the shape of the glue injection holes can be the same as the above embodiments.

[0051] Example 13 of the rear-expanded bottom anchor bolt of this utility model: Unlike the above examples, regardless of how many sets of injection holes are arranged, the position of the injection holes does not have to correspond to the position of the key plate. For example, the first injection hole that originally corresponded to the position of the first key plate is changed to correspond to the middle cylindrical part of the single key sleeve. When the anchor bolt also includes a double key sleeve, the second injection hole that originally corresponded to the position of the second key plate is changed to correspond to the middle cylindrical part of the double key sleeve.

[0052] Example 14 of the rear-expanded bottom anchor bolt of this utility model: Unlike the above examples, depending on the specific specifications of the anchor bolt, the number of the first key piece can also be three or six pieces. Of course, if the anchor bolt also includes a double key sleeve, the number of the second key pieces at both ends of the double key sleeve can also be three or six pieces.

[0053] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. A rear-expanded bottom anchor bolt, comprising an anchor rod and a sleeve fitted outside the anchor rod, and a first locking key, wherein the first locking key is integrally connected to the sleeve or separately disposed therefrom, the first locking key comprising a plurality of first key plates, and the end of the anchor rod having a tapered head for engaging with each of the first key plates to allow the first key plates to open outward when the anchor rod and the first locking key undergo axial relative movement, characterized in that, The anchor rod is a hollow anchor rod with an axially extending glue injection channel inside for injecting glue from the outside of the substrate. The wall of the anchor rod has a glue injection hole that communicates with the glue injection channel and penetrates the wall of the anchor rod so that the glue can flow into the mounting hole in the substrate.

2. The rear-expanded anchor bolt according to claim 1, characterized in that, The glue injection hole includes a first glue injection hole arranged corresponding to the position of the first key piece.

3. The rear-expanded anchor bolt according to claim 2, characterized in that, The rear-expanded bottom anchor bolt includes a single-key sleeve that is separately set from the sleeve. The first locking key is integrally connected to the single-key sleeve. The rear-expanded bottom anchor bolt also includes a double-key sleeve. The two ends of the double-key sleeve are respectively provided with a second locking key. The second locking key includes multiple second key pieces. The glue injection hole also includes a second glue injection hole arranged corresponding to the positions of the second key pieces at both ends.

4. The rear-expanded anchor bolt according to claim 3, characterized in that, The glue injection hole also includes a third glue injection hole arranged corresponding to the middle position of the double bond sleeve.

5. The rear-expanded anchor bolt according to claim 4, characterized in that, The first injection hole, two second injection holes, and the third injection hole are arranged at equal intervals along the axial direction of the anchor rod.

6. The rear-expanded anchor bolt according to claim 4 or 5, characterized in that, The second and third injection holes are both radially penetrating "I"-shaped holes that run through the anchor rod.

7. The rear-expanded anchor bolt according to claim 6, characterized in that, The direction of the third injection hole is perpendicular to the direction of the second injection holes on both sides.

8. The post-expanded anchor bolt according to any one of claims 2 to 5, characterized in that, The first injection hole is a cross-shaped hole that runs through the anchor rod in a radial direction perpendicular to each other.

9. The post-expanded anchor bolt according to any one of claims 1 to 5, characterized in that, The adhesive injection channel runs through the anchor bolt axially.

10. The rear-expanded anchor bolt according to claim 9, characterized in that, The portion of the glue injection channel located inside the conical head is funnel-shaped.

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