Prestressed anchor cable tensioning control device for roadway in close distance coal seam group

Abstract

This utility model discloses a prestressed anchor cable tensioning control device for closely spaced coal seam roadways, relating to the field of anchor cable tensioning technology. The device includes a hydraulic cylinder and an inner hydraulic cylinder; the anchor cable tensioning assembly includes a fixed frame with a movable plate slidably connected inside; a second anchor is located on the side of the fixed frame away from the inner hydraulic cylinder; a first anchor is located at the end of the hydraulic cylinder away from the inner hydraulic cylinder. The movement of the movable plate within the fixed frame, along with the arrangement of the first anchor, second anchor, and anchor cable clamps, facilitates the compression of the first anchor and anchor cable clamps by the fixed frame during tensioning, thus facilitating prestressed tensioning of the steel strands. It also facilitates tensioning the steel strands according to actual needs, allows the anchor cable clamps to lock the steel strands, and enables pressure relief from the hydraulic cylinder and inner hydraulic cylinder for tensioning the steel strands. This enhances the practicality and convenience of the device and improves its tensioning efficiency for the steel strands.

Description

Technical Field

[0001] This utility model relates to the field of anchor cable tensioning technology, and in particular to a prestressed anchor cable tensioning control device for closely spaced coal seam group roadways. Background Technology

[0002] Based on the relative positional relationship between the lower coal seam working face and the remaining protective coal pillar of the upper coal seam during close-range coal seam mining, the arrangement of the lower coal seam working face is divided into internal staggered arrangement, external staggered arrangement, and overlapping arrangement. The internal staggered arrangement includes unidirectional internal staggered and reverse internal staggered arrangements, in which the working face moves in the same direction and the mining roadway is arranged below the goaf of the first coal seam. In this arrangement, the length of the second coal seam mining face is relatively short, resulting in low coal extraction rate and resource waste. The external staggered arrangement refers to the arrangement of the remaining coal pillar of the first coal seam inside the second coal seam working face, and the second coal seam mining roadway is located outside the remaining coal pillar of the first coal seam. In this arrangement, the second coal seam mining face is relatively long, but the second coal seam mining roadway is easily affected by the stress of the remaining coal pillar of the first coal seam, and a reasonable stagger distance needs to be determined.

[0003] Prestressed anchor cable technology can effectively control the deformation of surrounding rock and improve the stability of roadways by applying high prestress. Its core lies in applying precise prestress to the anchor cable through a tensioning device and ensuring the stability of the prestress during long-term use. The tensioning control device is a key piece of equipment in prestressed anchor cable technology, mainly used to apply prestress to the anchor cable and control the tensioning process. Chinese utility model patent, authorized announcement number "CN213418521U", discloses an anchor cable tensioning device, including an outer cylinder, a middle cylinder, an inner cylinder, and a top pressure device. The middle cylinder is located inside the outer cylinder and its end protrudes from the outer cylinder. The inner cylinder is located inside the middle cylinder. The top pressure device is fixedly located at the end of the middle cylinder. The top pressure device is equipped with a top anchor tube, several disc springs, and a retraction ring. The top anchor tube is fixedly connected to the top pressure device, and the retraction ring is movably located inside the top pressure device.

[0004] The above technical solution introduces hydraulic oil into the inlet, which pushes the piston forward. The piston drives the middle cylinder forward. However, since the front end of the middle cylinder is blocked by the support point and cannot move, the outer and inner cylinders will move in the opposite direction under the reaction force. During the movement, there is frictional resistance between the threaded teeth on the inner surface of the tool anchor and the anchor cable. Under the action of the anchor, the anchor will contract towards the center and lock the anchor cable. Continuous oil supply can pull the anchor cable to move, achieving the purpose of outward tensioning. However, the above technical solution still has certain defects. When performing the first prestressing tensioning, after the tensioning exceeds the locking value, it cannot be directly depressurized to the locking value. It is necessary to unlock the anchor and re-tension and lock it, which is inconvenient to operate and has low work efficiency. Therefore, this utility model proposes a new solution. Utility Model Content

[0005] The purpose of this utility model is to at least solve one of the technical problems existing in the prior art, and to provide a prestressed anchor cable tensioning control device for close-range coal seam group roadways. This device can solve the problem that when the tensioning exceeds the locking value during the first prestressing tensioning, the pressure cannot be directly released to the locking value. The anchor needs to be unlocked and re-tensioned and locked, which is inconvenient to operate and has low work efficiency.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a prestressed anchor cable tensioning control device for close-range coal seam group roadways, comprising a hydraulic cylinder and a hydraulic inner cylinder;

[0007] An anchor cable tensioning assembly is mounted on a hydraulic cylinder. The anchor cable tensioning assembly includes a fixed frame, which is fixed to the hydraulic inner cylinder. The fixed frame is cylindrical and has a through hole. The cylindrical wall of the fixed frame is "C" shaped. A fixed plate is fixedly connected inside the fixed frame. A movable plate is slidably connected inside the fixed frame. A connecting rod and a threaded rod are fixedly connected to one end of the movable plate near the fixed plate.

[0008] The fixed plate has a threaded sleeve inside for rotational connection. The threaded sleeve is threaded onto the surface of the threaded rod. A nut is fixedly connected to the surface of the threaded sleeve. A second anchor is provided on the side of the fixed frame away from the hydraulic cylinder.

[0009] A first anchor is provided at the end of the hydraulic cylinder barrel away from the hydraulic inner cylinder, and both the first anchor and the second anchor have tapered grooves on their surfaces.

[0010] Preferably, the anchor cable tensioning assembly further includes two anchor cable clips, each of which is engaged with the interior of the corresponding first anchor and second anchor.

[0011] Both anchor cable clips are frustum-shaped and divided into two symmetrical segments.

[0012] The inner walls of both anchor cable clamps are fixedly connected with multiple retaining rings;

[0013] The surface of the second anchor has mounting holes.

[0014] Preferably, the hydraulic cylinder is hollow, the inner wall of the hydraulic cylinder is hollow, and the hydraulic inner cylinder is slidably connected inside the hydraulic cylinder.

[0015] A piston is fixedly connected to the surface of the hydraulic inner cylinder. The piston is annular and is slidably connected to the hydraulic cylinder barrel. A hydraulic cylinder cover is threadedly connected to the surface of the hydraulic cylinder barrel.

[0016] Preferably, the hydraulic cylinder has a hydraulic oil passage inside, and a first hydraulic pipe and a second hydraulic pipe are fixedly connected to the surface of the hydraulic cylinder.

[0017] Both the first and second hydraulic pipes are connected to the interior of the hydraulic cylinder.

[0018] Preferably, the connection between the hydraulic inner cylinder and the fixed frame is fixedly connected with a plurality of triangular reinforcing ribs.

[0019] Preferably, the fixed frame is internally fixed with strip-shaped reinforcing ribs.

[0020] Compared with the prior art, the beneficial effects of this utility model are:

[0021] 1. This prestressed anchor cable tensioning control device for close-range coal seam roadways, through the movement of a movable plate within a fixed frame and the arrangement of the first anchor, second anchor, and anchor cable wedges, facilitates the compression of the first anchor and anchor cable wedges by the fixed frame during tensioning, thus facilitating prestressed tensioning of the steel strands. The movement of the movable plate also allows the anchor cable wedges to be secured within the second anchor, enabling tensioning of the steel strands according to actual needs. Furthermore, the anchor cable wedges can lock the steel strands in place, and the hydraulic cylinder and inner cylinder can release pressure to tension the steel strands, enhancing the device's practicality and convenience, and improving its tensioning efficiency for the steel strands. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0023] Figure 1 This is a schematic diagram of the prestressed anchor cable tensioning control device for close-range coal seam group roadways according to this utility model;

[0024] Figure 2 This is a schematic diagram of the hydraulic inner cylinder of this utility model;

[0025] Figure 3 This is a schematic diagram of the hydraulic cylinder of this utility model;

[0026] Figure 4 This is a schematic diagram of the movable plate of this utility model;

[0027] Figure 5 This is a schematic diagram of the first anchorage of this utility model;

[0028] Figure 6 This is a schematic diagram of the second anchorage of this utility model;

[0029] Figure 7 This is a schematic diagram of the fixing ring of this utility model.

[0030] Reference numerals in the attached drawings: 1. Hydraulic cylinder barrel; 2. Hydraulic inner cylinder; 3. Hydraulic cylinder head; 4. First hydraulic pipe; 5. Second hydraulic pipe; 6. Fixing frame; 7. First anchor; 8. Second anchor; 9. Anchor cable clamp; 10. Fixing ring; 11. Fixing plate; 12. Movable plate; 13. Connecting rod; 14. Threaded sleeve; 15. Threaded rod; 16. Piston; 17. Hydraulic oil passage. Detailed Implementation

[0031] This section will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present utility model, but they should not be construed as limiting the scope of protection of the present utility model.

[0032] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0033] In the description of this utility model, terms such as greater than, less than, and exceeding are understood to exclude the stated number, while terms such as above, below, and within are understood to include the stated number. The use of terms like "first" and "second" is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the quantity or sequence of the indicated technical features.

[0034] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0035] Please see Figure 1-7 This utility model provides a technical solution: a prestressed anchor cable tensioning control device for close-range coal seam group roadways, including a hydraulic cylinder 1 and a hydraulic inner cylinder 2, and an anchor cable tensioning assembly. The anchor cable tensioning assembly is mounted on the hydraulic cylinder 1 and includes a fixed frame 6, which is fixed to the hydraulic inner cylinder 2. The fixed frame 6 is cylindrical and has a through hole. The cylindrical wall of the fixed frame 6 is C-shaped. A fixed plate 11 is fixedly connected inside the fixed frame 6, and a movable plate 12 is slidably connected inside the fixed frame 6. A connecting rod 13 and a threaded rod 15 are fixedly connected to one end of the movable plate 12 near the fixed plate 11. A threaded sleeve 14 is rotatably connected inside the fixed plate 11. The threaded sleeve 14 is threaded onto the surface of the threaded rod 15, and a nut is fixedly connected to the surface of the threaded sleeve 14. A second anchor 8 is provided on the side of the fixed frame 6 away from the hydraulic inner cylinder 2, and a first anchor 7 is provided on the side of the hydraulic cylinder 1 away from the hydraulic inner cylinder 2. Both the first anchor 7 and the second anchor 8 have conical grooves on their surfaces.

[0036] The anchor cable tensioning assembly also includes two anchor cable clips 9, which are snapped into the interior of the corresponding first anchor 7 and second anchor 8. Both anchor cable clips 9 are frustum-shaped and divided into two symmetrical sections. Multiple fixing rings 10 are fixedly connected to the inner walls of both anchor cable clips 9. The surface of the second anchor 8 is provided with mounting holes.

[0037] The hydraulic cylinder 1 is hollow, and the inner wall of the hydraulic cylinder 1 is hollow. The hydraulic inner cylinder 2 is slidably connected inside the hydraulic cylinder 1. A piston 16 is fixedly connected to the surface of the hydraulic inner cylinder 2. The piston 16 is annular and is slidably connected to the hydraulic cylinder 1. A hydraulic cylinder cover 3 is threadedly connected to the surface of the hydraulic cylinder 1.

[0038] The hydraulic cylinder 1 has a hydraulic oil passage 17 inside. The surface of the hydraulic cylinder 1 is fixedly connected to a first hydraulic pipe 4 and a second hydraulic pipe 5. Both the first hydraulic pipe 4 and the second hydraulic pipe 5 are connected to the inside of the hydraulic cylinder 1.

[0039] Multiple triangular reinforcing ribs are fixedly connected at the connection between the hydraulic inner cylinder 2 and the fixed frame 6.

[0040] The internal fixing connection of the fixed frame 6 has strip-shaped reinforcing ribs.

[0041] When using this device, based on the relative positional relationship between the lower coal seam working face and the protective coal pillar left by the upper coal seam during close-range coal seam mining, the prestressed anchor cable technology can effectively control the deformation of the surrounding rock and improve the stability of the roadway by applying high prestress. Its core lies in applying precise prestress to the anchor cable through the tensioning device and ensuring the stability of the prestress during long-term use. The tensioning control device is the key equipment of the prestressed anchor cable technology, mainly used to apply prestress to the anchor cable and control the tensioning process.

[0042] First, the steel strand is stripped. Then, the stripped steel strand is passed sequentially through the second anchor 8, the fixing frame 6, the hydraulic inner cylinder 2, the hydraulic cylinder barrel 1, and the first anchor 7. The anchor cable clamp 9 is then secured inside the first anchor 7. The first hydraulic pipe 4 and the second hydraulic pipe 5 are connected to external hydraulic equipment. Hydraulic oil is injected into the hydraulic cylinder barrel 1 through the second hydraulic pipe 5. The pressure of the hydraulic oil pushes the hydraulic inner cylinder 2 outward from the hydraulic cylinder barrel 1, changing the distance between the hydraulic cylinder barrel 1 and the fixing frame 6, thereby adjusting the distance between the first anchor 7 and the fixing frame 6. The spacing of the second anchor 8, when adjusting the position of the first anchor 7, facilitates the clamping of the anchor cable clamp 9 inside the first anchor 7 through friction between the anchor cable clamp 9 and the steel strand. This allows the anchor cable clamp 9 to be squeezed during the movement of the first anchor 7, and the steel strand to be squeezed during the squeezing of the anchor cable clamp 9. This helps maintain the stability of the position of the anchor cable clamp 9 and the steel strand, and facilitates the movement of the first anchor 7, which in turn moves the steel strand, facilitating the tensioning and prestressing of the steel strand.

[0043] Since over-tensioning or under-tensioning may occur during the prestressing tensioning process, when over-tensioning occurs, hydraulic oil can be injected into the interior of the hydraulic cylinder head 3 from the first hydraulic pipe 4, and the hydraulic oil inside the hydraulic cylinder head 3 can be withdrawn from the second hydraulic pipe 5. This facilitates the adjustment of the distance between the fixing frame 6 and the hydraulic cylinder 1, and helps to reduce the prestress of the steel strand.

[0044] When the tension is not yet in place, the anchor cable clamp 9 is installed inside the second anchor 8 and engaged with the second anchor 8. The nut on the surface of the threaded sleeve 14 is rotated using a wrench, causing the thread to rotate inside the fixed plate 11. Due to the threaded connection between the threaded rod 15 and the threaded sleeve 14, the threaded sleeve 14 moves the threaded rod 15 during rotation. The threaded rod 15 drives the movable plate 12 to move, and the movable plate 12 drives the connecting rod 13 to move inside the fixed plate 11. The fixed plate 11 guides the movement of the movable plate 12, facilitating its movement. To ensure stability during movement, the movable plate 12 is moved to contact the anchor cable clamp 9 inside the second anchor 8, and the anchor cable clamp 9 is inserted into the second anchor 8. The position of the steel strand is fixed by the anchor cable clamp 9. Hydraulic oil is injected into the hydraulic cylinder head 3 from the first hydraulic pipe 4, and the hydraulic oil inside the hydraulic cylinder head 3 is withdrawn from the second hydraulic pipe 5 to facilitate adjustment of the distance between the fixed frame 6 and the hydraulic cylinder 1. The anchor cable clamp 9 and the first anchor 7 are separated, and the first anchor 7 is brought close to the surface of the fixed frame 6 again. Then the above process is repeated to tension the steel strand.

[0045] By fixing multiple fixing rings 10 on the inner side of the anchor cable wedge 9, the fixing rings 10 can effectively limit the displacement of the anchor cable wedge 9 during the tensioning process, and prevent the anchor cable wedge 9 from slipping due to uneven force or vibration, thereby ensuring close contact between the anchor cable wedge 9 and the steel strand and ensuring stable transmission of tension force. The fixing rings 10 can reduce the direct friction and compression between the anchor cable wedge 9 and the surface of the steel strand, prevent the steel strand from being damaged due to local stress concentration during the tensioning process, and extend the service life of the steel strand. Through the constraint of the fixing rings 10, the contact between the anchor cable wedge 9 and the steel strand is more uniform, which can reduce stress loss during the tensioning process, improve the application accuracy of tension force, and ensure that the prestress meets the design requirements.

[0046] By installing reinforcing ribs at the connection between the hydraulic inner cylinder 2 and the fixed frame 6, the stability of the fixed frame 6 during fixation is improved. By fixing multiple strip-shaped reinforcing ribs to the inner wall of the fixed frame 6, the strength of the fixed frame 6 is strengthened, preventing the fixed frame 6 from deforming under the pressure of the hydraulic cylinder 1 and the hydraulic inner cylinder 2, thereby improving its load-bearing capacity and extending the service life of the structure.

[0047] After the steel strand is tensioned, the anchor clamp 9 is fixed inside the second anchor 8 to fix the position of the steel strand. Then, the hydraulic cylinder 1 and the hydraulic inner cylinder 2 are shortened to separate the first anchor 7 from the corresponding anchor clamp 9. The first anchor 7 is taken out, as are the hydraulic cylinder 1 and the hydraulic inner cylinder 2. The second anchor 8 is then installed on the inner wall of the tunnel through the mounting holes on its surface. Finally, the excess steel strand is cut.

[0048] Furthermore, the movement of the movable plate 12 within the fixed frame 6, along with the arrangement of the first anchor 7, the second anchor 8, and the anchor clamp 9, facilitates the compression of the first anchor 7 and the anchor clamp 9 by the fixed frame 6 during tensioning, thus facilitating prestressing of the steel strand. The movement of the movable plate 12 also allows the anchor clamp 9 to be secured within the second anchor 8, enabling tensioning of the steel strand according to actual needs. Furthermore, the anchor clamp 9 facilitates locking the steel strand, and the hydraulic cylinder 1 and hydraulic inner cylinder 2 can release pressure to tension the steel strand, enhancing the practicality and convenience of the device and improving its tensioning efficiency for the steel strand.

[0049] By fixing the fixing ring 10 inside the anchor cable clamp 9, the fixing ring 10 can effectively limit the displacement of the anchor cable clamp 9 during the tensioning process, and prevent the anchor cable clamp 9 from slipping due to uneven force or vibration, thereby ensuring close contact between the anchor cable clamp 9 and the steel strand and ensuring stable transmission of tension force. The fixing ring 10 can reduce the direct friction and compression of the anchor cable clamp 9 on the surface of the steel strand, prevent the steel strand from being damaged due to local stress concentration during the tensioning process, and extend the service life of the steel strand.

[0050] Structural Description: Hydraulic Cylinder 1: As the main supporting structure of the entire device, it is hollow and provides sliding space for the hydraulic inner cylinder 2;

[0051] The surface threaded connection of the hydraulic cylinder head 3, together with the hydraulic inner cylinder 2, piston 16, etc., constitutes the working space of the hydraulic system;

[0052] The internal hydraulic oil passage 17 is provided and is connected to external hydraulic equipment through the first hydraulic pipe 4 and the second hydraulic pipe 5, which is used to control the extension and retraction of the hydraulic inner cylinder 2.

[0053] Hydraulic inner cylinder 2: It is slidably connected inside the hydraulic cylinder 1, and a piston 16 is fixed on its surface. It is pushed by the pressure of hydraulic oil to move inside the hydraulic cylinder 1, thereby adjusting its relative position with the hydraulic cylinder 1 and realizing the adjustment of the anchor cable tensioning distance.

[0054] The upper fixed frame 6 is fixedly connected, which drives the fixed frame 6 and related components to move, thereby realizing the tensioning operation of the anchor cable;

[0055] Hydraulic cylinder head 3: Threaded connection to the surface of hydraulic cylinder 1, together with hydraulic cylinder 1 forming a closed hydraulic space to ensure that hydraulic oil works normally inside hydraulic cylinder 1;

[0056] First hydraulic pipe 4 and second hydraulic pipe 5: Both are connected to the inside of hydraulic cylinder 1. By connecting to external hydraulic equipment, hydraulic oil can be injected into or extracted from hydraulic cylinder 1 to control the extension and retraction of hydraulic inner cylinder 2.

[0057] Fixed frame 6: Fixed on the hydraulic inner cylinder 2, cylindrical in shape and with through holes, its cylindrical wall is "C" shaped; a fixed plate 11 is fixed inside, providing installation and movement space for components such as movable plate 12;

[0058] Multiple triangular reinforcing ribs are fixed at the connection with the hydraulic inner cylinder 2 to enhance the connection stability; strip-shaped reinforcing ribs are fixed inside to improve its own strength and prevent deformation under working pressure.

[0059] During the anchor cable tensioning process, the hydraulic inner cylinder 2 drives the first anchor 7 and the anchor cable wedge 9 to apply compressive force, thereby achieving prestress tensioning of the steel strand;

[0060] First anchor 7 and second anchor 8: First anchor 7 is located at the end of hydraulic cylinder 1 away from hydraulic inner cylinder 2, and second anchor 8 is located on the side of fixed frame 6 away from hydraulic inner cylinder 2;

[0061] The surface of each anchor has a tapered groove for engaging with the anchor clamp 9. During tensioning, the tapered structure generates a squeezing force on the anchor clamp 9, thereby clamping the steel strand and achieving tensioning and fixing of the steel strand. The surface of the second anchor 8 also has an installation hole for installing it on the inner wall of the roadway after tensioning.

[0062] Anchor cable clip 9: It is frustum shaped and divided into two symmetrical sections, which are snapped into the corresponding first anchor 7 and second anchor 8;

[0063] Multiple fixing rings 10 are fixedly connected to the inner wall. During the tensioning process, the fixing rings 10 can effectively limit the displacement of the anchor cable wedges 9, prevent them from slipping due to uneven force or vibration, ensure close contact with the steel strand, and stably transmit the tension force; at the same time, reduce direct friction and squeezing on the surface of the steel strand, prevent damage to the steel strand, and extend its service life.

[0064] By cooperating with the first anchor 7 and the second anchor 8, the steel strand is clamped during the tensioning process, thereby achieving tensioning and position locking of the steel strand;

[0065] Fixed ring 10: Fixed to the inner wall of anchor cable clamp 9, it plays a role in limiting the displacement of anchor cable clamp 9, reducing friction and extrusion on the surface of steel strand, ensuring stable transmission of tension force and improving the accuracy of tension force application; Fixed plate 11: Fixed inside the fixed frame 6, with internal rotatable threaded sleeve 14, it provides guidance for the movement of movable plate 12 and ensures the stability of movable plate 12 when it moves.

[0066] Movable plate 12: It is slidably connected inside the fixed frame 6, and the connecting rod 13 and threaded rod 15 are fixedly connected at one end near the fixed plate 11; through the threaded connection between the threaded rod 15 and the threaded sleeve 14, the movable plate 12 is moved when the threaded sleeve 14 rotates, thereby realizing the compression and fixation of the anchor cable clamp 9 in the second anchor 8, which facilitates the tensioning operation of the steel strand according to actual needs.

[0067] Connecting rod 13: It is fixed on the movable plate 12 and moves inside the fixed plate 11 when the movable plate 12 moves, thus assisting the movable plate 12 to move stably.

[0068] Threaded sleeve 14: Rotatably connected inside the fixed plate 11, threadedly sleeved on the surface of the threaded rod 15; by turning the nut on its surface with a wrench, it rotates inside the fixed plate 11, driving the threaded rod 15 to move, thereby realizing the movement of the movable plate 12;

[0069] Threaded rod 15: threadedly connected to threaded sleeve 14, one end of which is fixed to movable plate 12. When threaded sleeve 14 rotates, it drives movable plate 12 to move.

[0070] Piston 16: It is ring-shaped and fixed on the surface of the hydraulic inner cylinder 2. It is slidably connected to the hydraulic cylinder barrel 1. Under the action of hydraulic oil pressure, it pushes the hydraulic inner cylinder 2 to move inside the hydraulic cylinder barrel 1.

[0071] Hydraulic oil passage 17: Located inside the hydraulic cylinder 1, it provides a channel for the flow of hydraulic oil within the hydraulic cylinder 1, ensuring the normal operation of the hydraulic system.

[0072] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A prestressed anchor cable tensioning control device for closely spaced coal seam roadways, characterized in that: It includes a hydraulic cylinder barrel (1) and a hydraulic inner cylinder (2); An anchor cable tensioning assembly is set on a hydraulic cylinder (1). The anchor cable tensioning assembly includes a fixed frame (6), which is fixed on a hydraulic inner cylinder (2). The fixed frame (6) is cylindrical and has a through hole. The cylindrical wall of the fixed frame (6) is "C" shaped. A fixed plate (11) is fixedly connected inside the fixed frame (6). A movable plate (12) is slidably connected inside the fixed frame (6). A connecting rod (13) and a threaded rod (15) are fixedly connected to one end of the movable plate (12) near the fixed plate (11). The fixed plate (11) is rotatably connected to a threaded sleeve (14), which is threaded onto the surface of the threaded rod (15). A nut is fixedly connected to the surface of the threaded sleeve (14). A second anchor (8) is provided on the side of the fixed frame (6) away from the hydraulic cylinder (2). The hydraulic cylinder (1) is provided with a first anchor (7) at the end away from the hydraulic inner cylinder (2), and the surfaces of the first anchor (7) and the second anchor (8) are both provided with conical grooves.

2. The prestressed anchor cable tensioning control device for closely spaced coal seam roadways according to claim 1, characterized in that: The anchor cable tensioning assembly also includes two anchor cable clips (9), which are snapped into the interior of the corresponding first anchor (7) and second anchor (8); Both anchor clips (9) are frustum-shaped and are divided into two symmetrical segments. The inner walls of both anchor clips (9) are fixedly connected with multiple fixing rings (10); The surface of the second anchor (8) has mounting holes.

3. The prestressed anchor cable tensioning control device for closely spaced coal seam roadways according to claim 1, characterized in that: The hydraulic cylinder (1) is hollow, the inner wall of the hydraulic cylinder (1) is hollow, and the hydraulic inner cylinder (2) is slidably connected inside the hydraulic cylinder (1). The surface of the hydraulic inner cylinder (2) is fixedly connected to a piston (16), which is in the shape of an annulus. The piston (16) is slidably connected to the hydraulic cylinder (1), and the surface of the hydraulic cylinder (1) is threadedly connected to a hydraulic cylinder cover (3).

4. The prestressed anchor cable tensioning control device for closely spaced coal seam roadways according to claim 1, characterized in that: The hydraulic cylinder (1) has a hydraulic oil passage (17) inside, and a first hydraulic pipe (4) and a second hydraulic pipe (5) are fixedly connected to the surface of the hydraulic cylinder (1). Both the first hydraulic pipe (4) and the second hydraulic pipe (5) are connected to the interior of the hydraulic cylinder (1).

5. The prestressed anchor cable tensioning control device for closely spaced coal seam roadways according to claim 1, characterized in that: Multiple triangular reinforcing ribs are fixedly connected at the connection between the hydraulic inner cylinder (2) and the fixed frame (6).

6. The prestressed anchor cable tensioning control device for closely spaced coal seam roadways according to claim 1, characterized in that: The fixed frame (6) is internally fixed with strip-shaped reinforcing ribs.

Images