Three-piece type expansion shell anchor rod and method for anchoring through three-piece type expansion shell anchor rod

Abstract

The invention belongs to the technical field of surrounding rock support in geotechnical engineering. According to the three-piece type expansion shell anchor rod and the method for anchoring through the three-piece type expansion shell anchor rod, three-point large-angle stress is achieved, and the three-piece type expansion shell anchor rod can rotationally enter an anchor hole in the process of entering the anchor hole. According to the technical scheme, the anchor rod comprises an anchor head and a rod body, in the anchor head, a connecting section is a hollow cylinder, an inner wedge head is fixed to the end face of the connecting section, the interior of the inner wedge head is hollow to form a pushing cavity, the inner diameter of the pushing cavity is larger than that of the connecting section, and a retaining step is formed; the three wedge sheets are installed in the three wedge surfaces in a sliding mode through a guide mechanism, the guide mechanism comprises a T-shaped guide rail and a T-shaped guide groove, a clamping head is arranged at the bottom of a flange of the T-shaped guide rail, groove-shaped pushing openings are formed in the bottoms of the three wedge surfaces, and the clamping head is pushed into the pushing cavity from the groove-shaped pushing openings; the front end of the rod body is connected with the connecting section through threads, and a retaining spring rod is installed on the rod body close to the front end head. The anchor rod is used for anchor rod supporting of surrounding rocks.

Description

Technical Field

[0001] This invention relates to a three-piece expansion shell anchor bolt and a method for anchoring it, belonging to the field of geotechnical engineering surrounding rock support technology. Background Technology

[0002] Rock bolts play an effective role in strengthening and stabilizing soil and rock masses in various reinforcement projects, improving the bearing capacity of the soil and rock mass and greatly enhancing the safety of construction. Expandable hollow rock bolts, due to their ease of installation and ability to provide active support immediately after excavation, have found good application in hard rock.

[0003] In existing expansion anchor bolt technology, the anchor head is mostly supported by two wedges that push from both sides or rotate outwards to contact the rock wall for stress. This has problems such as small angle, easy wedge detachment and failure. At the same time, the construction method is to push in and then rotate to expand. During the process of the anchor bolt entering the anchor hole, it is a static push, which makes it difficult to enter. If it cannot enter the anchor hole, it is necessary to re-drill the hole. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a three-piece expansion shell anchor rod and a method for anchoring it, which can be subjected to force at three large angles and can be rotated into the anchor hole during the process of entering the anchor hole.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a three-piece expansion shell anchor bolt, comprising an anchor head and a rod body. The anchor head includes a connecting section, an inner wedge head, and wedge plates. The connecting section is a hollow cylinder. The inner wedge head is fixed on the end face of the connecting section. The interior of the inner wedge head is hollow, forming a pushing cavity. The bottom of the pushing cavity is connected to the connecting section, and the inner diameter of the pushing cavity is larger than the inner diameter of the connecting section, forming a step to prevent backlash. Three sets of wedge surfaces are opened on the side of the inner wedge head. Three wedge plates are slidably installed in the three sets of wedge surfaces through a guide mechanism. The guide mechanism includes a T-shaped guide rail set in the lower part of the wedge plate and a T-shaped guide groove set in the upper part of the inner wedge head. The T-shaped guide rail is slidably fitted in the T-shaped guide groove. A clamp is provided at the bottom of the flange of the T-shaped guide rail. The width and height of the clamp protrude beyond the width and height of the flange of the T-shaped guide rail. The bottom surface of the clamp is flush with the bottom surface of the wedge plate. The bottom of each of the three sets of wedge surfaces is provided with a groove-shaped push port. The clamp is pushed into the pushing cavity from the groove-shaped push port. The front end of the rod is connected to the connecting section by a thread, and the end extends into the push cavity and presses against the clamp head. A radial anti-reverse through hole is provided on the rod near the front end, and an anti-reverse spring rod is installed in the anti-reverse through hole. The anti-reverse spring rod includes a hollow rod, a spring, a push plate, and a stop rod. The spring is fitted inside the hollow rod, and push plates are fixed at both ends of the spring. One end of the stop rod is fixed to the push plate, and the other end of the stop rod extends out of the hollow rod and is engaged with the anti-reverse step. The length of the hollow rod is adapted to the diameter of the rod body.

[0006] Preferably, the rod is a hollow rod.

[0007] Preferably, the upper side of the inner wedge head is provided with multiple slurry outlets that connect the pushing chamber and the outside.

[0008] Preferably, the present invention further includes a grout-stopping ring, a sealing ring, a washer, and a nut. The grout-stopping ring, the sealing ring, and the washer are sequentially fitted onto the tail end of the rod. The nut is threadedly connected to the tail end of the rod and is tightly attached to the washer.

[0009] Preferably, the rod is a single, integral piece, or is composed of multiple rods joined together by an intermediate connecting sleeve.

[0010] Preferably, the distance between the anti-reverse through hole and the front end of the rod body is 1 cm.

[0011] Preferably, the outer surfaces of the three wedges are provided with scales, and the scales are barbed.

[0012] The method of anchoring with a three-piece expansion shell anchor includes the following steps: S1. Determine the location of the anchor bolt holes and drill holes using an anchor bolt drilling machine; S2. Assemble a three-piece expansion shell anchor bolt; S3. Insert the assembled three-piece expansion shell anchor into the anchor drilling machine and align it with the anchor hole. Start the anchor drilling machine. While pushing, the anchor drilling machine rotates in the opposite direction, pushing the three-piece expansion shell anchor and causing the three-piece expansion shell anchor to rotate in the opposite direction as a whole, so as to reach the bottom of the hole smoothly. S4. After reaching the bottom of the hole, the anchor drilling rig rotates in the forward direction, which drives the rod to rotate in the forward direction. The front end of the rod extends into the jacking cavity, and the jacking wedge pushes along the wedge face until the rod can no longer be pushed forward. At this time, the three wedges are at their maximum angle and generate cutting friction with the rock mass. S5. Install the grout stop ring, sealing ring and gasket onto the end of the rod in sequence, then screw the nut into the end of the rod and tighten it against the gasket. Continue to screw the nut to apply preload to the rod. S6. After the pre-tightening force is reached, use a grouting machine to grout from the tail of the rod. Stop grouting after the grout fills the entire anchor hole. S7. After the grout reaches the required strength, a pull-out test will be conducted to verify the anchoring effect. S8. Periodically measure the deformation of the surrounding rock and compare it with the pressure relief of the rod to comprehensively assess the safety of the surrounding rock.

[0013] Preferably, the step of assembling the three-piece expansion shell anchor bolt in step S2 is as follows: a. Assemble the anchor head: Push the clips on the three wedges into the jacking cavity from the grooved inlet, and slide the T-shaped guide rails on the wedges into the T-shaped guide grooves on the inner wedges; b. Assemble the anchor head and rod body to form a three-piece expansion shell anchor bolt: First, insert the anti-reverse spring rod into the anti-reverse through hole at the front end of the rod body, then screw the front end of the rod body into the connecting end of the anchor head until the anti-reverse spring rod enters the jacking cavity and the stop rod pops out. Rotate the rod body in the opposite direction until the rod body and anchor head cannot separate.

[0014] After assembly, the front end of the rod pushes the chuck on the wedge upwards a certain distance, locking it against the inner wall of the inner wedge. Simultaneously, the T-shaped guide rail slides partially into the T-shaped guide groove, ensuring the wedge is securely connected to the inner wedge and will not detach. Meanwhile, the stop spring rod's stop bar is locked onto the stop step, preventing the rod and anchor head from separating. In S3, when the anchor drilling rig drives the rod to rotate in the opposite direction, due to the stop spring rod, the rod cannot retract relative to the anchor head, thus causing the anchor head to rotate in the opposite direction as well. The three-piece expanding shell anchor rod advances and rotates simultaneously, clearing loose soil from the anchor hole and allowing it to smoothly enter the bottom of the hole.

[0015] Compared with the prior art, the present invention has the following beneficial effects.

[0016] 1. In this invention, the anchor head includes three wedges. After the three wedges are pushed open, they are embedded in the surrounding rock. The three wedges are subjected to force at a large angle, resulting in good force distribution and making them less likely to fall off.

[0017] 2. In this invention, the T-shaped guide rail on the wedge plate and the T-shaped guide groove on the inner wedge head cooperate, and the clamp at the bottom of the flange of the T-shaped guide rail cooperates with the groove-shaped push port on the wedge surface. After being screwed into the front end of the rod, the wedge plate and the inner wedge head are firmly connected and do not fall off.

[0018] 3. In this invention, a backstop spring rod is installed at the front end of the rod body, and a backstop step is set inside the anchor head. The backstop spring rod and the backstop step work together to prevent the rod body from separating from the anchor head when it reverses, and can also drive the anchor head to reverse together, making the process of entering the anchor bolt hole smoother and reducing the situation where the anchor bolt cannot enter due to hole collapse and needs to be drilled again or re-drilled. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly introduced below.

[0020] Figure 1 This is a schematic diagram of the structure of the three-piece expansion shell anchor bolt of the present invention.

[0021] Figure 2 This is a schematic diagram of the operation of the three-piece expansion shell anchor bolt of the present invention.

[0022] Figure 3 This is a schematic diagram of the anchor head structure in the three-piece expansion shell anchor bolt of the present invention. Figure 1 .

[0023] Figure 4 This is a schematic diagram of the anchor head structure in the three-piece expansion shell anchor bolt of the present invention. Figure 2 .

[0024] Figure 5 This is a schematic diagram of the anchor head structure in the three-piece expansion shell anchor bolt of the present invention. Figure 3 .

[0025] Figure 6 This is a schematic diagram of the anti-retraction spring rod in the three-piece expansion shell anchor rod of the present invention.

[0026] In the diagram: 1 is the anchor head, 11 is the connecting section, 12 is the inner wedge head, 121 is the wedge surface, 122 is the T-shaped guide groove, 123 is the groove-shaped inlet, 124 is the slurry outlet, 13 is the wedge plate, 131 is the T-shaped guide rail, 132 is the clamp, 133 is the scale, 14 is the jacking cavity, 2 is the rod body, 21 is the stop hole, 22 is the intermediate connecting sleeve, 3 is the stop spring rod, 31 is the hollow rod, 32 is the spring, 33 is the push plate, 34 is the stop rod, 4 is the slurry ring, 5 is the sealing ring, 6 is the pad, and 7 is the nut. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The present invention provides the following embodiments.

[0029] In this embodiment, the direction in which the rod 2 is screwed into the connecting section 11 is considered positive, and the direction in which it is screwed out is considered negative.

[0030] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, the present invention discloses a three-piece expansion shell anchor bolt, comprising an anchor head 1 and a rod body 2. The anchor head 1 includes a connecting section 11, an inner wedge head 12, and wedge plates 13. The connecting section 11 is a hollow cylinder. The inner wedge head 12 is fixed to the end face of the connecting section 11. The interior of the inner wedge head 12 is hollow, forming a pushing cavity 14. The bottom of the pushing cavity 14 communicates with the connecting section 11, and the inner diameter of the pushing cavity 14 is larger than the inner diameter of the connecting section 11, forming a step to prevent backlash. Three sets of wedge surfaces 121 are opened on the side of the inner wedge head 12. Three wedge plates 13 are slidably installed in the three sets of wedge surfaces 121 through a guide mechanism. The guiding mechanism includes a T-shaped guide rail 131 located in the lower part of the wedge 13 and a T-shaped guide groove 122 located in the upper part of the inner wedge head 12. The T-shaped guide rail 131 is slidably fitted in the T-shaped guide groove 122. A locking head 132 is provided at the bottom of the flange of the T-shaped guide rail 131. The width and height of the locking head 132 protrude beyond the width and height of the flange of the T-shaped guide rail 131. The bottom surface of the locking head 132 is flush with the bottom surface of the wedge 13. The bottom of each of the three sets of wedge surfaces 121 is provided with a groove-shaped push port 123. The locking head 132 is pushed into the push cavity 14 from the groove-shaped push port 123. The front end of the rod 2 is connected to the connecting section 11 by a thread, and the end extends into the push cavity 14 and abuts against the chuck 132. A radial anti-reverse through hole 21 is provided on the rod 2 near the front end, and an anti-reverse spring rod 3 is installed in the anti-reverse through hole 21. like Figure 6 As shown, the anti-reverse spring rod 3 includes a hollow rod 31, a spring 32, a push plate 33, and a stop rod 34. The spring 32 is fitted inside the hollow rod 31, and push plates 33 are fixed to both ends of the spring 32. One end of the stop rod 34 is fixed to the push plate 33, and the other end of the stop rod 34 extends out of the hollow rod 31 and is locked on the anti-reverse step. The length of the hollow rod 31 is adapted to the diameter of the rod body 2.

[0031] A flexible bushing can be provided between the anti-reverse spring rod 3 and the anti-reverse through hole 21, so that the anti-reverse spring rod 3 can be easily inserted into the anti-reverse through hole 21 and will be stably fixed in the anti-reverse through hole 21 after insertion, and will not easily slip out. The stop rod 34 can be completely retracted into the anti-reverse through hole 21 without affecting the threaded connection between the rod body 2 and the connecting section 11. When the anti-reverse spring rod 3 is in position and enters the push cavity 14 with the forward rotation of the rod body 2, the stop rod 34 pops out. After popping out, the stop rod 34 will be stuck on the anti-reverse step, and there is a gap between its end and the inner wall of the push cavity 14, which will not hinder the subsequent forward rotation of the rod body 2.

[0032] The rod 2 is a hollow rod.

[0033] The upper side of the inner wedge head 12 is provided with multiple connecting push chambers 14 and external slurry outlets 124.

[0034] The invention also includes a grout-stopping ring 4, a sealing ring 5, a pad 6, and a nut 7. The grout-stopping ring 4, the sealing ring 5, and the pad 6 are sequentially fitted onto the tail end of the rod body 2. The nut 7 is threadedly connected to the tail end of the rod body 2 and is tightly attached to the pad 6.

[0035] The rod 2 is a single piece, or it can be composed of multiple rods connected by an intermediate connecting sleeve 22.

[0036] The distance between the anti-reverse through hole 21 and the front end of the rod body 2 is 1cm.

[0037] Each of the three wedges 13 has scales 133 on its outer surface, and the scales 133 are barbed.

[0038] The present invention uses a three-piece expansion shell anchor bolt for anchoring, comprising the following steps: S1. Determine the location of the anchor bolt holes and drill holes using an anchor bolt drilling machine; S2. Assemble a three-piece expansion shell anchor bolt; S3. Insert the assembled three-piece expansion shell anchor into the anchor drilling machine and align it with the anchor hole. Start the anchor drilling machine. While pushing, the anchor drilling machine rotates in the opposite direction, pushing the three-piece expansion shell anchor and causing the three-piece expansion shell anchor to rotate in the opposite direction as a whole, so as to reach the bottom of the hole smoothly. S4. After reaching the bottom of the hole, the anchor drilling machine rotates in the forward direction, which drives the rod body 2 to rotate in the forward direction. The front end of the rod body 2 extends into the push cavity 14, and the push wedge 13 pushes forward along the wedge surface 121 until the rod body 2 can no longer be pushed forward. At this time, the three wedges 13 are at their maximum angle and generate cutting friction with the rock mass. S5. Install the grout stop ring 4, sealing ring 5 and pad 6 onto the tail end of the rod body 2 in sequence, then screw the nut 7 into the tail end of the rod body 2 and tighten it against the pad 6. Continue to screw the nut 7 to apply a pre-tightening force to the rod body 2. S6. After the pre-tightening force is reached, use a grouting machine to grout from the tail of rod 2. Stop grouting after the grout fills the entire anchor hole. S7. After the grout reaches the required strength, a pull-out test will be conducted to verify the anchoring effect. S8. Periodically measure the deformation of the surrounding rock and compare it with the pressure relief of rod 2 to comprehensively assess the safety of the surrounding rock.

[0039] The steps for assembling the three-piece expansion shell anchor bolt in S2 are as follows: a. Assemble anchor head 1: Push the clips 132 on the three wedges 13 into the push cavity 14 from the grooved inlet 123, and slide the T-shaped guide rails 131 on the wedges 13 into the T-shaped guide grooves 122 on the inner wedge head 12. b. Assemble the anchor head 1 and the rod body 2 to form a three-piece expansion shell anchor: First, insert the anti-reverse spring rod 3 into the anti-reverse through hole 21 at the front end of the rod body 2, and then screw the front end of the rod body 2 into the connecting end of the anchor head 1 until the anti-reverse spring rod 3 enters the push cavity 14 and the stop rod 34 pops out. Rotate the rod body 2 in the opposite direction until the rod body 2 and the anchor head 1 cannot be separated.

[0040] In this invention, after the anchor head 1 and the rod body 2 are assembled, the front end of the rod body extends into the jacking cavity 14 by about 1 cm, pushing the locking head 132 on the wedge plate 13 upward. The locking head 132 moves upward, offset from the groove-shaped inlet 123, and locks onto the inner wall of the inner wedge head 12. At the same time, the T-shaped guide rail 131 also slides into the T-shaped guide groove 122, so that the wedge plate 13 is firmly connected to the inner wedge head 12 and will not detach. Meanwhile, the stop bar 34 of the anti-reverse spring rod 3 is locked on the anti-reverse step, and the rod body 2 cannot retract and detach from the anchor head 1. In S3, when the anchor drilling machine drives the rod body 2 to rotate in the opposite direction, due to the anti-reverse spring rod 3, the rod body 2 cannot retract relative to the anchor head 1, so it drives the anchor head 1 to rotate in the opposite direction. The three-piece expansion shell anchor rod is pushed forward and rotated at the same time, which can clear the scattered soil in the anchor rod hole and make it smoothly enter the bottom of the hole, reducing the situation where the anchor rod cannot enter due to hole collapse and needs to be drilled again or re-drilled.

[0041] After the anchor head 1 reaches the bottom of the hole, the rod body 2 is rotated in the forward direction. The rod body 2 pushes out the three wedges 13 along the T-shaped guide groove 122 and the wedge surface 121. The three wedges 13 open and cut into the rock mass, generating friction. The force is well received and they are not easy to fall off.

[0042] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A three-piece expansion shell anchor bolt, characterized in that: The system includes an anchor head (1) and a rod body (2). The anchor head (1) includes a connecting section (11), an inner wedge head (12), and wedge plates (13). The connecting section (11) is a hollow cylinder. The inner wedge head (12) is fixed on the end face of the connecting section (11). The interior of the inner wedge head (12) is hollow, forming a push-pull cavity (14). The bottom of the push-pull cavity (14) is connected to the connecting section (11), and the inner diameter of the push-pull cavity (14) is larger than the inner diameter of the connecting section (11), forming a step to prevent backlash. Three sets of wedge surfaces (121) are opened on the side of the inner wedge head (12). Three wedge plates (13) are slidably installed in the three sets of wedge surfaces (121) through a guide mechanism. The guide mechanism includes... Includes a T-shaped guide rail (131) set in the lower part of the wedge (13) and a T-shaped guide groove (122) set in the upper part of the inner wedge (12). The T-shaped guide rail (131) is slidably fitted in the T-shaped guide groove (122). A locking head (132) is provided at the bottom of the flange of the T-shaped guide rail (131). The width and height of the locking head (132) are both greater than the width and height of the flange of the T-shaped guide rail (131). The bottom surface of the locking head (132) is flush with the bottom surface of the wedge (13). The bottom of the three sets of wedge surfaces (121) is provided with a groove-shaped push port (123). The locking head (132) is pushed into the push cavity (14) from the groove-shaped push port (123). The front end of the rod (2) is connected to the connecting section (11) by a thread, and the end extends into the push cavity (14) and presses against the chuck (132). A radial anti-reverse through hole (21) is provided on the rod (2) near the front end, and an anti-reverse spring rod (3) is installed in the anti-reverse through hole (21). The anti-reverse spring rod (3) includes a hollow rod (31), a spring (32), a push plate (33), and a stop rod (34). The spring (32) is fitted inside the hollow rod (31). Both ends of the spring (32) are fixed with push plates (33). One end of the stop rod (34) is fixed on the push plate (33), and the other end of the stop rod (34) extends out of the hollow rod (31) and is locked on the anti-reverse step. The length of the hollow rod (31) is adapted to the diameter of the rod body (2).

2. The three-piece expansion shell anchor bolt according to claim 1, characterized in that: The rod (2) is a hollow rod.

3. A three-piece expansion shell anchor bolt according to claim 1 or 2, characterized in that: The upper side of the inner wedge (12) is provided with multiple connecting push chambers (14) and external slurry outlets (124).

4. A three-piece expansion shell anchor bolt according to claim 1 or 2, characterized in that: It also includes a grout stop ring (4), a sealing ring (5), a pad (6) and a nut (7). The grout stop ring (4), the sealing ring (5) and the pad (6) are sequentially fitted onto the tail end of the rod body (2). The nut (7) is threadedly connected to the tail end of the rod body (2) and is tightly attached to the pad (6).

5. A three-piece expansion shell anchor bolt according to claim 1 or 2, characterized in that: The rod (2) is a single piece or is composed of multiple pieces connected by an intermediate connecting sleeve (22).

6. A three-piece expansion shell anchor bolt according to claim 1 or 2, characterized in that: The distance between the anti-reverse through hole (21) and the front end of the rod (2) is 1cm.

7. A three-piece expansion shell anchor bolt according to claim 1 or 2, characterized in that: The outer surfaces of the three wedges (13) are provided with scales (133), and the scales (133) are barbed.

8. The method of anchoring using the three-piece expansion shell anchor bolt as described in claim 1, characterized in that... Includes the following steps: S1. Determine the location of the anchor bolt holes and drill holes using an anchor bolt drilling machine; S2. Assemble a three-piece expansion shell anchor bolt; S3. Insert the assembled three-piece expansion shell anchor into the anchor drilling machine and align it with the anchor hole. Start the anchor drilling machine. While pushing, the anchor drilling machine rotates in the opposite direction, pushing the three-piece expansion shell anchor and causing the three-piece expansion shell anchor to rotate in the opposite direction as a whole, so as to reach the bottom of the hole smoothly. S4. After reaching the bottom of the hole, the anchor drill rotates in the forward direction, which drives the rod (2) to rotate in the forward direction. The front end of the rod (2) extends into the jacking cavity (14), and the jacking wedge (13) pushes forward along the wedge surface (121) until the rod (2) can no longer be pushed forward. At this time, the three wedges (13) are at their maximum angle and generate cutting friction with the rock mass. S5. Place the grout stop ring (4), sealing ring (5) and pad (6) onto the tail end of the rod (2) in sequence, and then screw the nut (7) into the tail end of the rod (2) so that it is tightly attached to the pad (6). Continue to screw the nut (7) to apply a preload to the rod (2). S6. After the pre-tightening force is reached, use a grouting machine to grout from the tail of the rod (2). Stop grouting after the grout fills the entire anchor hole. S7. After the grout reaches the required strength, a pull-out test will be conducted to verify the anchoring effect. S8. Periodically measure the deformation of the surrounding rock and compare it with the pressure relief of the rod (2) to comprehensively assess the safety of the surrounding rock.

9. The method for anchoring with a three-piece expansion shell anchor bolt according to claim 8, characterized in that: The steps for assembling the three-piece expansion shell anchor bolt in S2 are as follows: a. Assemble the anchor head (1): Push the clips (132) on the three wedges (13) into the push cavity (14) from the groove-shaped push port (123), and slide the T-shaped guide rail (131) on the wedge (13) into the T-shaped guide groove (122) on the inner wedge (12); b. Assemble the anchor head (1) and the rod body (2) to form a three-piece expansion shell anchor: First, insert the anti-reverse spring rod (3) into the anti-reverse through hole (21) at the front end of the rod body (2), and then screw the front end of the rod body (2) into the connecting end of the anchor head (1) until the anti-reverse spring rod (3) enters the push cavity (14) and the stop rod (34) pops out. Rotate the rod body (2) in the opposite direction until the rod body (2) and the anchor head (1) cannot be separated.

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