Coupling pressure-yielding energy-releasing anchor rod for supporting coal mine tunnel

Abstract

The utility model discloses a coupling yielding energy-releasing anchor rod for supporting a coal mine tunnel, which comprises an anchor rod body, a tray, a yielding device and a locking nut, the tray is movably sleeved on the anchor rod body, the locking nut is screwed at the rear end of the anchor rod body, and the tray is positioned in front of the locking nut. And the yielding device is positioned between the tray and the locking nut. The yielding device comprises a fixed outer shell, a yielding outer shell and a spring adjusting mechanism, and the fixed outer shell and the yielding outer shell are each of a cylindrical shell structure. The fixed shell is adjacently arranged on the front side of the locking nut, the yielding shell is adjacently arranged on the rear side of the tray, the rear end of the yielding shell is inserted into the fixed shell and is in sliding fit with the outer wall of the fixed shell, and the side wall of the front portion of the yielding shell is of a thin-wall structure. The multiple spring adjusting mechanisms are annularly and evenly arranged on the inner side of the fixed shell. The anchor rod is simple in structure and convenient to install, and can not only keep good anchoring performance, but also achieve a good yielding effect when surrounding rock of a roadway deforms greatly.

Description

Technical Field

[0001] The utility model relates to the technical field of support equipment, and particularly relates to a coupling yielding energy-releasing bolt for supporting coal mine roadways. Background Art

[0002] In the field of modern mine exploitation, the stability of roadway surrounding rock has always been a key issue concerning safety and efficiency. Although traditional bolt support technology can provide effective support for roadway surrounding rock to a certain extent, in the face of complex geological conditions and large deformations that may occur in the surrounding rock, the uneven stress distribution and stress concentration effect often lead to a decline in the anchoring performance. Especially when subjected to a large tensile force, local stress concentration phenomena are likely to occur, reducing the overall anchoring efficiency of the bolt and even losing its original bearing capacity, thus affecting the safety and stability of the entire roadway structure and being unable to meet the yielding requirements in the environment of large deformation of the surrounding rock.

[0003] At present, for the situation of complex and changeable geological conditions or large deformations of the surrounding rock, the reaction force of the rock wall on the tray increases sharply, and existing bolts are often difficult to adjust flexibly to meet the changing support requirements. Especially when the surrounding rock undergoes large deformations, the yielding performance of the bolt is limited, and it cannot effectively disperse or release the surrounding rock pressure, resulting in a sharp increase in the tensile force of the bolt and causing the anchoring performance of the bolt to fail. Therefore, the existing technology urgently needs to be further improved and enhanced. Summary of the Utility Model

[0004] Aiming at the deficiencies of the above-mentioned existing technology, the purpose of the utility model is to provide a coupling yielding energy-releasing bolt for supporting coal mine roadways, which can achieve efficient stress transfer and yielding performance of the bolt system in the environment of large deformation roadway surrounding rock, and effectively improve the adaptability and anchoring stability of the bolt under complex geological conditions.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is as follows:

[0006] A coupling yielding energy-releasing bolt for supporting coal mine roadways includes a bolt body, a tray, a yielding device and a locking nut. The tray is movably sleeved on the bolt body, the locking nut is screwed on the rear end of the bolt body, and the tray is located in front of the locking nut.

[0007] The yielding device is located between the tray and the locking nut and is sleeved outside the bolt body.

[0008] The yielding device includes a fixed outer shell, a yielding outer shell and a spring adjusting mechanism. Both the fixed outer shell and the yielding outer shell are cylindrical shell structures and are coaxially arranged with the bolt body.

[0009] The fixed housing is arranged adjacent to the front side of the locking nut, and the yielding housing is arranged adjacent to the rear side of the tray. The rear end of the yielding housing is inserted into the interior of the fixed housing and is in sliding fit with its outer wall along the axial direction of the bolt body. The front side wall of the yielding housing adopts a thin-wall structure.

[0010] There are multiple spring adjusting mechanisms, and all the spring adjusting mechanisms are arranged evenly in a ring on the inner side of the fixed housing. The front end of each spring adjusting mechanism is fixedly connected to the yielding housing, and the rear end is fixedly connected to the fixed housing.

[0011] Furthermore, the tray is a square metal plate, and a circular hole through which the bolt body can pass is provided at its central position.

[0012] The bolt body includes an anchoring section and a free section. The free section is located at the rear side of the anchoring section, and the outer wall of the free section has external threads that match the locking nut.

[0013] Furthermore, the fixed housing includes a cylindrical wall and a rear end plate. The rear end plate is a circular flat plate, and its outer edge is fixedly welded to the rear end of the cylindrical wall to form an integral body. A first central hole is provided at the center of the rear end plate.

[0014] An inner sleeve coaxial with it is provided on the inner side of the cylindrical wall. The rear end of the inner sleeve is fixedly connected to the rear end plate to form an integral body, and its interior communicates with the first central hole. An annular cavity is formed between the inner sleeve and the cylindrical wall.

[0015] Furthermore, the yielding housing includes a yielding cylindrical wall and a front end plate. The front end plate is a circular flat plate, and its outer edge is fixedly welded to the front end of the yielding cylindrical wall to form an integral body. A second central hole is provided at the center of the front end plate.

[0016] A plurality of guide chutes are arranged evenly in a ring on the inner side of the cylindrical wall. Each guide chute extends from the middle section of the cylindrical wall to its front end face. An annular limiting portion integral with it is provided on the inner side of the cylindrical wall, and the annular limiting portion is arranged adjacent to the rear end of each guide chute.

[0017] Guide sliders equal in number to the guide chutes and corresponding in position are provided on the outer side of the rear end of the yielding cylindrical wall. Each guide slider is located in the corresponding guide chute and is in sliding fit with the cylindrical wall.

[0018] Furthermore, the yielding cylindrical wall includes an equal-section segment and a variable-diameter segment. The equal-section segment is a circular tube structure with an equal cross-section, and the outer diameter of the equal-section segment is equal to the inner diameter of the cylindrical wall. The rear end of the variable-diameter segment and the front end of the equal-section segment are of an integral structure.

[0019] The variable-diameter segment is in the shape of a thin-walled spherical shell that is thick in the middle and thin at both ends. The wall thickness of the variable-diameter segment is 1 / 3 to 1 / 2 of the wall thickness of the equal-section segment. The front end of the variable-diameter segment is fixedly connected to the outer edge of the front end plate to form an integral body.

[0020] Further, the spring adjusting mechanism includes a guide seat, a guide rod and a spring. The rear end of the guide seat is fixedly connected to the rear end plate, the front end of the guide rod is fixedly connected to the front end plate, and the rear end thereof is inserted into the guide seat and is slidably engaged with the guide seat.

[0021] The spring is sleeved outside the guide rod and is located between the guide seat and the front end plate, and the rear end of the spring presses against the front end face of the guide seat.

[0022] Further, the inner side of the yielding cylinder wall has an outer sleeve arranged coaxially therewith. The front end of the outer sleeve is fixedly connected and integrated with the front end plate, and its interior communicates with the second central hole.

[0023] The front end of the inner sleeve is inserted into the interior of the outer sleeve and is slidably engaged with the outer sleeve.

[0024] By adopting the above technical solutions, the beneficial technical effects of the present utility model are as follows:

[0025] 1. The present utility model significantly improves the stress state of the bolt under the tensile condition through the yielding device, and effectively alleviates the problem that the anchoring force of the bolt fails due to the stress concentration of the surrounding rock.

[0026] 2. In the case of large deformation of the roadway surrounding rock, it can not only maintain excellent anchoring performance, but also achieve excellent yielding effect, so as to meet the requirements of roadway support under complex geological conditions.

[0027] 3. The structure of the present utility model is simple, and it is convenient to install on site. When the roadway surrounding rock undergoes large deformation, it can not only maintain good anchoring property, but also achieve good yielding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a schematic structural diagram of a coupling yielding energy-releasing bolt for supporting a coal mine roadway according to the present utility model.

[0029] Figure 2 is a cross-sectional view of a coupling yielding energy-releasing bolt for supporting a coal mine roadway according to the present utility model.

[0030] Figure 3 is a diagram of the use state of a coupling yielding energy-releasing bolt for supporting a coal mine roadway according to the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The present utility model will be described in detail below with reference to the accompanying drawings:

[0032] Example, in combination with Figures 1 to 3, A coupling pressure-relieving and energy-releasing bolt for supporting coal mine roadways, comprising a bolt body 1, a tray 2, a pressure-relieving device and a locking nut 3. The bolt body 1 includes an anchoring section and a free section, and the free section is located at the rear side of the anchoring section. The outer wall of the free section has external threads matching the locking nut 3. Before construction, a drill hole needs to be drilled in the rock wall of the roadway surrounding rock using a drill, and the inside of the drill hole is cleaned. The anchoring section of the bolt body 1 is inserted into the drill hole of the roadway surrounding rock. Then, grout is injected into the drill hole, and the mortar solidifies into concrete between the anchoring section of the bolt body 1 and the inner wall of the drill hole, fixing the bolt body 1 inside the surrounding rock, and the anchoring section of the bolt body 1 extends outside the rock wall.

[0033] The tray 2 is a square metal plate, and a round hole through which the bolt body 1 can pass is provided at its central position. The tray 2 is movably sleeved on the bolt body 1, the locking nut 3 is screwed onto the rear end of the bolt body 1, and the tray 2 is located in front of the locking nut 3. The pressure-relieving device is located between the tray 2 and the locking nut 3 and is sleeved on the outside of the bolt body 1. The tray 2 is inserted from the end of the anchoring section and pushed against the rock wall of the surrounding rock to make it adhere to the rock wall. Then, the pressure-relieving device is inserted from the end of the anchoring section, sleeved on the outside of the anchoring section and pushed to the rear side of the tray 2. The locking nut 3 is screwed into the rear end of the bolt body 1 and tightened on the bolt body 1 to apply a certain pre-tightening force.

[0034] Specifically, the pressure-relieving device includes a fixed outer shell 4, a pressure-relieving outer shell 5 and a spring adjusting mechanism 6. Both the fixed outer shell 4 and the pressure-relieving outer shell 5 are cylindrical shell structures and are arranged coaxially with the bolt body 1. The fixed outer shell 4 includes a cylindrical wall 41 and a rear end plate 42. The rear end plate 42 is a circular flat plate, and its outer edge is fixedly welded to the rear end of the cylindrical wall 41 to form an integral body. A first central hole is provided at the center of the rear end plate 42. During installation, the rear end of the bolt body 1 passes through the first central hole and passes out from the rear side of the fixed outer shell 4.

[0035] The fixed outer shell 4 is arranged adjacent to the front side of the locking nut 3. The inner side of the cylindrical wall 41 has an inner sleeve 43 arranged coaxially with it. The rear end of the inner sleeve 43 is fixedly connected to the rear end plate 42 to form an integral body. Its interior is communicated with the first central hole. An annular cavity is formed between the inner sleeve 43 and the cylindrical wall 41. The guide seats 61 of the six spring adjusting mechanisms 6 are arranged inside the annular cavity and are evenly distributed on the circumference with the center of the first central hole as the center.

[0036] The pressure-relieving outer shell 5 includes a pressure-relieving cylindrical wall 51 and a front end plate 52. The front end plate 52 is a circular flat plate, and the outer edge of the front end plate 52 is fixedly welded to the front end of the pressure-relieving cylindrical wall 51 to form an integral body. A second central hole is provided at the center of the front end plate 52. The front end plate 52 is connected and arranged on the rear side wall of the tray 2. In the working state, the front end plate 52 presses against the tray 2.

[0037] The inner side of the yield pressure cylinder wall 51 has an outer sleeve 53 arranged coaxially therewith. The front end of the outer sleeve 53 is fixedly connected to the front end plate 52 integrally, and its interior communicates with the second central hole. The front end of the inner sleeve 43 is inserted into the interior of the outer sleeve 53 and is in sliding fit with the outer sleeve 53. The guide rods 62 of the six spring adjusting mechanisms 6 are arranged between the outer sleeve 53 and the yield pressure cylinder wall 51 and are evenly distributed on the circumference centered on the center of the second central hole.

[0038] The yield pressure housing 5 is arranged adjacent to the rear side of the tray 2. The rear end of the yield pressure housing 5 is inserted into the interior of the fixed housing 4 and is in sliding fit with its outer wall along the axial direction of the anchor body 1. The front side wall of the yield pressure housing 5 adopts a thin-wall structure.

[0039] Specifically, the inner side of the cylindrical wall 41 has six guide chutes 44 arranged annularly and evenly. Each guide chute 44 extends from the middle section of the cylindrical wall 41 to its front end face. The inner side of the cylindrical wall 41 has an annular limiting portion 45 integrally formed therewith. The annular limiting portion 45 is arranged adjacent to the rear end of each guide chute 44. The outer side of the rear end of the yield pressure cylinder wall 51 is provided with guide sliders 54 having the same number as and corresponding positions to the guide chutes 44. Each guide slider is in sliding fit with the cylindrical wall 41 in the corresponding guide chute 44.

[0040] During the installation process, each guide slider 54 enters the corresponding guide chute 44 from the front end of the cylindrical wall 41, causing the yield pressure cylinder wall 51 to slide relative to the cylindrical wall 41. When the rear end of the yield pressure cylinder wall 51 contacts the annular limiting portion 45, the annular limiting portion 45 limits the movement of the yield pressure cylinder wall 51, blocks the yield pressure cylinder wall 51 from moving relative to the yield pressure cylinder wall 51, and supports the yield pressure cylinder wall 51.

[0041] The yield pressure cylinder wall 51 includes an equal cross-section section 511 and a variable diameter section 512. The equal cross-section section 511 is a circular tube structure with an equal cross-section. The outer diameter of the equal cross-section section 511 is equal to the inner diameter of the cylindrical wall 41. The rear end of the variable diameter section 512 and the front end of the equal cross-section section 511 are integrally formed. The variable diameter section 511 is a thin-walled spherical shell shape that is thick in the middle and thin at both ends. The wall thickness of the variable diameter section 512 is 1 / 3 to 1 / 2 of the wall thickness of the equal cross-section section 511. The front end of the variable diameter section 512 is fixedly welded to the outer edge of the front end plate 52 integrally.

[0042] There are six spring adjusting mechanisms 6. All the spring adjusting mechanisms 6 are arranged annularly and evenly on the inner side of the fixed housing 4. The front end of each spring adjusting mechanism 6 is fixedly connected to the yield pressure housing 5, and its rear end is fixedly connected to the fixed housing 4.

[0043] Specifically, the spring adjusting mechanism 6 includes a guide seat 61, a guide rod 62 and a spring 63. The rear end of the guide seat 61 is fixedly connected to the rear end plate 42, the front end of the guide rod 62 is fixedly connected to the front end plate 52, and the rear end thereof is inserted into the guide seat 61 and is slidably engaged with the guide seat 61. The spring 63 is sleeved outside the guide rod 62 and is located between the guide seat 61 and the front end plate 52, and the rear end of the spring 63 presses on the front end face of the guide seat 61.

[0044] After the bolt body 1 is fixed in the roadway surrounding rock, the tray 2 is installed on the bolt body 1. First, the yielding housing 5 is sleeved on the bolt body 1 and pushed to the rear side of the tray 2. After the spring 63 is placed on each guide rod 62, the fixed housing 4 is placed on the bolt body 1, so that the rear end of the bolt body 1 passes through the rear end plate 42 of the fixed housing 4. The fixed housing 4 is pushed forward to make the inner sleeve 43 penetrate into the inside of the outer sleeve 53, and the fixed housing 4 is rotated and adjusted so that the front ports of the respective guide rods 62 are aligned with the corresponding guide seats 61, and the rear end of the guide rod 62 is inserted into the guide seat 61. At the same time, the six guide sliders 54 respectively enter the corresponding guide chutes 44, and the fixed housing 4 is pushed forward to the natural elongation state of the spring 63. Then, the locking nut 3 is screwed into and tightened from the rear end of the bolt body 1. During the tightening process of the locking nut 3, the fixed housing 4 moves forward relative to the yielding housing 5, and the spring 6 is continuously compressed. After reaching the set pre-tightening force, the locking nut 3 stops, and the bolt body 1 maintains the set prestress.

[0045] When large deformation occurs in the roadway surrounding rock, the reaction force of the rock wall of the roadway surrounding rock on the tray 2 will suddenly increase. The yielding housing 5 is pushed by the tray 2 to move backward relative to the fixed housing 4, and the spring 6 is continuously compressed until the annular limiting portion 45 limits the movement of the yielding cylinder wall 51, and the reaction force of the rock wall on the tray 2 is released, and the bolt body 1 remains anchored inside the surrounding rock. When the deformation of the roadway surrounding rock continues to increase or suddenly increases, the variable diameter section 512 of the yielding cylinder wall 51 is deformed under force and is squeezed and deformed, and the reaction force of the rock wall on the tray 2 is continuously released until the rear end of the guide rod 62 contacts the bottom of the cavity of the guide seat 61, reaching a new equilibrium state, and the bolt body 1 continues to be anchored in the roadway surrounding rock.

[0046] The parts not described in the present utility model can be realized by adopting or referring to the existing technologies.

[0047] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0048] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0049] Certainly, the above description is not a limitation to the present utility model, and the present utility model is not limited to the above examples either. Changes, modifications, additions or substitutions made by those skilled in the art within the scope of the essence of the present utility model should also fall within the protection scope of the present utility model.

Claims

1. A coupled pressure-release anchor for coal mine tunnel support, characterized in that: It includes an anchor rod body, a tray, a pressure relief device and a locking nut. The tray is movably sleeved on the anchor rod body, the locking nut is screwed on the rear end of the anchor rod body, and the tray is located in front of the locking nut. The pressure-releasing device is located between the tray and the locking nut and is sleeved on the outside of the anchor rod body; The pressure-releasing device comprises a fixed shell, a pressure-releasing shell and a spring adjustment mechanism, wherein the fixed shell and the pressure-releasing shell are both cylindrical shell structures and are coaxially arranged with the anchor rod body; The fixed shell is arranged adjacent to the front side of the locking nut, and the pressure-releasing shell is arranged adjacent to the rear side of the tray. The rear end of the pressure-releasing shell is inserted into the interior of the fixed shell and slides with the outer wall thereof along the axial direction of the anchor rod body. The front side wall of the pressure-releasing shell adopts a thin-wall structure. There are multiple spring adjustment mechanisms, all of which are evenly arranged in a ring shape on the inner side of the fixed shell. The front end of each spring adjustment mechanism is fixedly connected to the pressure-releasing shell, and the rear end is fixedly connected to the fixed shell.

2. According to claim 1, a coupled pressure-release anchor for coal mine tunnel support, characterized in that: The tray is a square metal plate, and a circular hole is provided at the center thereof for the anchor rod to pass through; The anchor rod body comprises an anchoring section and a free section, wherein the free section is located at the rear side of the anchoring section, and the outer wall of the free section is provided with an outer thread matching with a locking nut.

3. According to claim 1, a coupled pressure-release anchor for coal mine tunnel support, characterized in that: The fixed housing comprises a cylindrical wall and a rear end plate, the rear end plate is a circular flat plate and the outer edge is fixedly welded to the rear end of the cylindrical wall as a whole, and a first central hole is opened in the center of the rear end plate; The inner side of the cylindrical wall is provided with an inner sleeve arranged coaxially therewith, the rear end of the inner sleeve is fixedly connected to the rear end plate as a whole, the interior of the inner sleeve is communicated with the first central hole, and an annular cavity is formed between the inner sleeve and the cylindrical wall.

4. The coupled pressure-release anchor for coal mine tunnel support according to claim 3, characterized in that: The pressure-releasing housing comprises a pressure-releasing cylinder wall and a front end plate, wherein the front end plate is a circular flat plate, the outer edge of the front end plate is fixedly welded to the front end of the pressure-releasing cylinder wall, and a second center hole is opened in the center of the front end plate; The inner side of the cylindrical wall has a plurality of guide grooves evenly arranged in an annular shape, each guide groove extends from the middle section of the cylindrical wall to the front end surface thereof, and the inner side of the cylindrical wall has an annular limiting portion integrally formed therewith, the annular limiting portion being adjacently arranged at the rear end of each guide groove; The outer side of the rear end of the pressing cylinder wall is provided with guide sliding blocks whose number is equal to the guide sliding grooves and whose positions correspond to each other. Each guide sliding block is located in the corresponding guide sliding groove and slides in cooperation with the cylinder wall.

5. The coupled pressure-release anchor for coal mine tunnel support according to claim 4, characterized in that: The pressure-releasing cylinder wall includes a constant-section section and a variable-diameter section, the constant-section section is a circular tube structure with a constant cross-section, the outer diameter of the constant-section section is equal to the inner diameter of the cylinder wall, and the rear end of the variable-diameter section is an integral structure with the front end of the constant-section section; The diameter-reducing section is in the shape of a thin-walled spherical shell with a thick middle and thin ends. The wall thickness of the diameter-reducing section is 1 / 3 to 1 / 2 of the wall thickness of the equal-section section. The front end of the diameter-reducing section is fixedly connected to the outer edge of the front end plate as a whole.

6. The coupled pressure-release anchor for coal mine tunnel support according to claim 4, characterized in that: The spring adjustment mechanism comprises a guide seat, a guide rod and a spring, wherein the rear end of the guide seat is fixedly connected to the rear end plate, the front end of the guide rod is fixedly connected to the front end plate, and the rear end of the guide rod is inserted into the guide seat and slidably cooperates with the guide seat; The spring sleeve is arranged outside the guide rod and is located between the guide seat and the front end plate, and the rear end of the spring is pressed on the front end surface of the guide seat.

7. The coupled pressure-release anchor for coal mine tunnel support according to claim 4, characterized in that: The inner side of the pressure cylinder wall has an outer sleeve arranged coaxially therewith, the front end of the outer sleeve is fixedly connected to the front end plate as a whole, and the interior of the outer sleeve is communicated with the second center hole; The front end of the inner sleeve is inserted into the interior of the outer sleeve and is slidably matched with the outer sleeve.

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