Rock bolt adapter

Abstract

To provide a rock bolt adapter that prevents a base end of the rock bolt from coming off.SOLUTION: A rock bolt adapter 35 detachably attached to a drifter 22 that is movable along a guide cell comprises an adapter main body 45 having a connecting portion 51 connected to the drifter 22 at a base end, and a recess 61 at a distal end into which the base end of the rock bolt 36 can be inserted from the distal end side of the guide cell, and a bolt magnet 71 disposed between the connecting portion 51 and the recess 61 in the adapter body 45 and capable of forming a magnetic field in the recess 61.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a rock bolt adapter used to attach a rock bolt to a drifter. [Background technology]

[0002] In tunnel construction, rock bolts are installed around the tunnel surface as one of the purposes of stabilizing the ground around the excavation cross section. The installation of rock bolts is carried out in the following order: drilling holes for the rock bolts with a drilling machine, filling the holes with grout, and inserting the rock bolts into the holes. For example, Patent Document 1 discloses a rock bolt installation device that performs this series of operations. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-65536 Summary of the Invention [Problem to be solved by the invention]

[0004] In the rock bolt installation device of Patent Document 1, the base end of the rock bolt is inserted into the rock bolt hole by moving the drifter while the base end of the rock bolt is inserted into the foot pad, which moves together with the drifter. However, because the base end of the rock bolt is simply inserted into the foot pad, there is a risk that the rock bolt may come off the foot pad during the process of placing the rock bolt in the desired position. [Means for solving the problem]

[0005] The lock bolt adapter that solves the above problem is an adapter for a lock bolt that is detachably attached to a drifter that can move along a guide cell, and includes an adapter body that has a connection part at its base end that connects to the drifter and a recess at its tip end into which the base end of a lock bolt can be inserted from the tip side of the guide cell, and a bolt magnet that is arranged between the connection part and the recess in the adapter body and uses magnetic force to hold the base end of the lock bolt inserted in the recess. [Effects of the Invention]

[0006] According to the present invention, the base end of the lock bolt is less likely to come off from the recess. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing a schematic configuration of a construction machine to which an embodiment of a rock bolt adapter is attached. [Figure 2] FIG. 2 is a diagram illustrating a schematic configuration of a unit. [Figure 3] FIG. 10 is a diagram showing a state in which a lock bolt is attached to a drifter via a lock bolt adapter. [Figure 4] FIG. 2 is a perspective view showing a lock bolt adapter. [Figure 5] This is a diagram showing a lock bolt adapter together with the base end of the lock bolt, where the side above the rotation axis is a diagram showing the side, and the side below the rotation axis is a diagram showing the internal structure. [Figure 6] (a) is a diagram showing a schematic diagram of the state in which the position adjustment of the unit is completed when inserting the rock bolt, and (b) is a diagram showing a schematic diagram of the state when the drifter is moved toward the base end side of the guide cell after the rock bolt is inserted. DETAILED DESCRIPTION OF THE INVENTION

[0008] One embodiment of a rock bolt adapter will be described with reference to Figures 1 to 6. First, with reference to Figure 1, a drilling machine 10, which is an example of construction machinery to which a rock bolt adapter can be attached, will be described. The drilling machine 10 is located within a tunnel 12 formed in natural ground 11 and performs operations such as drilling rock bolt holes 14 using a drilling rod 13 on the peripheral surface 12a of the tunnel 12 and driving rock bolts. These rock bolt holes 14 are filled with grout material and then the rock bolts are inserted.

[0009] The drilling machine 10 comprises a unit 15. The unit 15 is connected to a boom 18 via a coupler 17. The coupler 17 enables the unit 15 to perform various operations relative to the boom 18, such as raising and lowering, turning and rolling. The unit 15 is configured to be positionable at a desired position within the tunnel 12 by the boom 18. The drilling machine 10 also comprises a man cage 19 on which a worker can ride. The man cage 19 is configured to be positionable at a desired position within the tunnel 12 by the boom 20, similar to the unit 15.

[0010] As shown in Figure 2, the unit 15 includes a guide cell 21 and a drifter 22. The guide cell 21 extends in one direction. The base end of the guide cell 21 is connected to the tip of the boom 18 via a coupler 17. A holding mechanism 23 that rotatably holds the drilling rod 13 is provided at the tip of the guide cell 21.

[0011] The drifter 22 is supported by the guide cell 21. The drifter 22 is configured to be movable along the extension direction of the guide cell 21. The drifter 22 is configured so that the threaded portion at the tip end thereof can rotate around a rotation axis 24 that extends along the extension direction of the guide cell 21.

[0012] A drilling adapter 30 is detachably attached to the tip of the drifter 22. The drilling adapter 30 is used to attach the drilling rod 13 to the drifter 22. The base end of the drilling rod 13 is detachably attached to the drilling adapter 30, for example, by a screw connection structure. The drilling adapter 30 is configured to be able to transmit rotation of the tip of the drifter 22 to the drilling rod 13 as rotation about the rotation axis 24. The drilling machine 10 places the unit 15 in the desired position with the drilling rod 13 attached to the drifter 22, and then moves the drifter 22 toward the tip of the guide cell 21 while rotating the drilling rod 13, thereby drilling the rock bolt hole 14.

[0013] 3, a lock bolt adapter 35 is detachably attached to the tip of the drifter 22. The lock bolt adapter 35 is used when attaching a lock bolt 36 to the drifter 22. The lock bolt 36 is attached to the drifter 22 so that it is held by the holding mechanism 23 at the tip of the guide cell 21 and so that its central axis is aligned with the rotation axis 24.

[0014] (Rock bolt) As shown in Figure 5, the lock bolt 36 is made of a magnetic material. The lock bolt 36 has a lock bolt body 37. The base end of the lock bolt 36 has a nut 38 and a protrusion 39 protruding from the nut 38. The nut 38 is attached to the lock bolt body 37 using a threaded connection structure. The protrusion 39 protrudes a predetermined length from the nut 38. The lock bolt 36 also has a washer 41 disposed between the peripheral surface 12a of the tunnel 12 and the nut 38. This washer 41 may be a separate member from the nut 38, or may be integral with the nut 38.

[0015] (Rock bolt adapter) 4 and 5, the lock bolt adapter 35 (hereinafter simply referred to as the adapter 35) has an adapter body 45. When attached to the drifter 22, the adapter body 45 has an elongated shape that follows the direction of movement of the drifter 22. The adapter body 45 is formed so that its central axis coincides with the rotation axis 24 of the drifter 22 when attached to the drifter 22.

[0016] The adapter body 45 is composed of a drifter connection member 46 and a bolt attachment member 47. The drifter connection member 46 and the bolt attachment member 47 are manufactured by performing various machining processes on, for example, non-magnetic metal material. The drifter connection member 46 and the bolt attachment member 47 are connected by a screw connection.

[0017] The drifter connecting member 46 has a connecting portion 51 and a cylindrical portion 52. The connecting portion 51 is a portion that is connected to the tip end of the drifter 22. In this embodiment, assuming that the tip end of the drifter 22 is male threaded, the connecting portion 51 has a female thread portion 53 formed therein.

[0018] The cylindrical portion 52 is a portion that extends from the connection portion 51 toward the tip of the guide cell 21 when the adapter 35 is attached to the drifter 22. The tip of the cylindrical portion 52 is open. An engagement surface 55, which is two flat surfaces parallel to each other, is formed on the outer circumferential surface of the cylindrical portion 52. The engagement surface 55 is a surface that can be engaged with a tool such as a wrench when attaching or detaching the adapter 35 to the drifter 22. A bolt mounting member 47 is connected to the tip of the cylindrical portion 52 by a threaded connection structure.

[0019] The bolt mounting member 47 has a recess 61 that opens to an end face that is located on the tip end side of the guide cell 21. The recess 61 is formed in a shape that allows the base end of the lock bolt 36 to be inserted therein. Specifically, the recess 61 is formed in a shape that allows the nut 38 and the protrusion 39 to fit together.

[0020] The bolt mounting member 47 has a flange portion 62 that protrudes radially from the rotation axis 24 around the opening of the recess 61. The flange portion 62 is a portion that is disposed opposite the washer 41 of the lock bolt 36 when the base end of the lock bolt 36 is inserted into the recess 61.

[0021] As shown in FIG. 5, washer magnets 63 are arranged at predetermined intervals around the flange portion 62. The washer magnets 63 are permanent magnets. The washer magnets 63 are placed in through-holes formed in the flange portion 62, and then the openings of the through-holes are blocked with blocking members 64, thereby attaching the washer magnets 63 to the flange portion 62. The washer magnets 63 have a magnetic force sufficient to maintain the washer 41 in contact with the flange portion 62. Furthermore, the washer magnets 63 have a magnetic force sufficient to detach the washer 41 when the drifter 22 moves toward the base end of the guide cell 21 after the rock bolt 36 is inserted into the rock bolt hole 14 filled with grout. Note that FIG. 4 shows the rock bolt adapter 35 without the blocking members 64.

[0022] The connection work between the drifter connection member 46 and the bolt attachment member 47 is performed with the biasing member 70 and the bolt magnet 71 disposed inside the cylindrical portion 52 of the drifter connection member 46. The biasing member 70 is located on the connection portion 51 side, and the bolt magnet 71 is located on the tip end side of the cylindrical portion 52.

[0023] The bolt magnet 71 is held in contact with the bottom of the recess 61 formed in the bolt mounting member 47 by the biasing force of the biasing member 70. The bolt magnet 71 has a magnetic force that can hold the base end of the rock bolt 36 inserted in the recess 61. The bolt magnet 71 also has a magnetic force that can separate the rock bolt 36 by moving the drifter 22 toward the base end of the guide cell 21 after the rock bolt 36 is inserted into the rock bolt hole 14 filled with grout material.

[0024] (action) When driving a rock bolt 36 into a rock bolt hole 14 filled with grout, first, the drifter 22 is placed on the base end side of the guide cell 21, and the adapter 35 is attached to the drifter 22. Then, while the rock bolt 36 is held by the holding mechanism 23, the base end of the rock bolt 36 is inserted into the recess 61 of the adapter 35.

[0025] The base end of the lock bolt 36 inserted into the recess 61 is held in place by the magnetic force of the bolt magnet 71. When the washer 41 comes into contact with the flange 62, it is held in place by the magnetic force of the washer magnet 63.

[0026] 6(a), after the position of the unit 15 has been adjusted so that the rock bolt 36 can be inserted into the rock bolt hole 14 filled with grout material 75, the drifter 22 is moved toward the tip of the guide cell 21. The drifter 22 moves until the washer 41 abuts against the natural ground 11. This inserts the rock bolt 36 into the rock bolt hole 14.

[0027] 6(b), when the rock bolt 36 is inserted into the rock bolt hole 14, the drifter 22 is moved toward the base end of the guide cell 21. At this time, the frictional force generated between the rock bolt 36 and the grout material 75 is greater than the magnetic force received from the various magnets 63, 71, so the rock bolt 36 is detached from the adapter 35 while still inserted in the rock bolt hole 14.

[0028] The effects of this embodiment will be described. (1) The adapter 35 includes an adapter body 45 having a connecting portion 51 at its base end and a recess 61 at its tip end, and a bolt magnet 71 disposed in the adapter body 45 and capable of forming a magnetic field in the recess 61. This makes it difficult for the base end of the lock bolt 36 to come off the recess 61.

[0029] (2) The bolt magnet 71 is biased toward the bottom of the recess 61 by the biasing member 70. This configuration allows the bolt magnet 71 to be maintained in the vicinity of the recess 61 while reducing the weight of the adapter 35.

[0030] (3) The adapter body 45 is composed of a drifter connecting member 46 and a bolt mounting member 47. The drifter connecting member 46 and the bolt mounting member 47 are connected together with the biasing member 70 and the bolt magnet 71 disposed inside the cylindrical portion 52 of the drifter connecting member 46. This allows the biasing member 70 and the bolt magnet 71 to be disposed inside the adapter body 45.

[0031] Furthermore, by providing the biasing member 70, it is possible to reduce the weight of the adapter 35 while suppressing the magnetic force of the bolt magnet 71 acting on the tip of the drifter 22. It is also possible to ensure a space in the cylindrical portion 52 where the engagement surface 55 can be formed.

[0032] (4) The drifter connecting member 46 has two parallel engaging surfaces 55 on the outer circumferential surface of the cylindrical portion 52. This prevents deformation of the drifter connecting member 46 even when the adapter 35 is repeatedly attached to and detached from the drifter 22 using a tool such as a wrench.

[0033] (5) The base end of the lock bolt 36 has a nut 38. The recess 61 is formed in a shape that fits the nut 38. This makes it possible to prevent the lock bolt 36 from rotating.

[0034] (6) The adapter body 45 has a flange 62 around the opening of the recess 61. A washer magnet 63 is disposed on the flange 62. This ensures that the washer 41 remains in contact with the flange 62.

[0035] This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility. The adapter 35 does not need to have the washer magnet 63 disposed on the flange portion 62. Even with this configuration, it is possible to use the magnetic force of the bolt magnet 71 to hold the washer 41 on the flange portion 62. Also, the adapter 35 does not need to have the flange portion 62. Even with this configuration, the washer 41 can be abutted near the opening of the recess 61.

[0036] The recess 61 may have any shape as long as the base end of the lock bolt 36 can be inserted therein. In other words, the recess 61 may have any shape as long as the nut 38 and the protrusion 39 can be inserted therein. The adapter 35 does not have to be formed with the engagement surface 55. Even with this configuration, attachment and detachment can be performed using a tool such as a wrench.

[0037] The adapter body 45 is not limited to a configuration consisting of the drifter connection member 46 and the bolt attachment member 47. For example, the adapter body 45 may be configured to have a member having the connection portion 51, a member having the recess 61, and a connecting member that connects these members.

[0038] The cylindrical portion 52 may be configured so that only the bolt magnet 71 is disposed inside. [Explanation of symbols]

[0039] 10...drilling machine, 11...natural ground, 12...tunnel, 12a...surface, 13...drilling rod, 14...rock bolt hole, 15...unit, 17...coupler, 18...boom, 19...management gauge, 20...boom, 21...guide cell, 22...drifter, 23...holding mechanism, 24...rotation axis, 30...drilling adapter, 35...rock bolt adapter, 36...rock bolt, 37...rock bolt body, 38...nut, 39...protrusion, 41...washer, 45...adapter body, 46...drifter connecting member, 47...bolt mounting member, 51...connection portion, 52...cylindrical portion, 53...female thread portion, 55...engagement surface, 61...recess, 62...flange portion, 63...washer magnet, 64...blocking member, 70...biasing member, 71...bolt magnet, 75...grout material.

Claims

1. A rock bolt adapter that is detachably attached to a drifter that is movable along a guide cell, an adapter body having a connection portion at a base end portion thereof that is connected to the drifter, and a recess at a tip end portion thereof into which the base end of a lock bolt can be inserted from the tip side of the guide cell; a bolt magnet that is disposed between the connection portion and the recess in the adapter body and that uses magnetic force to hold the base end of the lock bolt inserted into the recess. Adapter for rock bolts.

2. a biasing member disposed between the connection portion and the bolt magnet for biasing the bolt magnet toward the bottom of the recess; The adapter for a lock bolt according to claim 1.

3. The adapter body is configured by connecting a drifter connecting member having the connecting portion and a bolt mounting member having the recessed portion, the drifter connecting member has a cylindrical portion extending from the connecting portion toward the bolt mounting member, the opening of the tip of which is closed by the bottom of the recess, The biasing member and the bolt magnet are disposed inside the cylindrical portion. The lock bolt adapter according to claim 2.

4. The cylindrical portion has two flat surfaces parallel to the outer circumferential surface thereof. The lock bolt adapter according to claim 3.

5. The base end of the lock bolt has a nut, The recess is formed in a shape that allows the nut to fit therein. The adapter for a lock bolt according to any one of claims 1 to 4.

6. A flange portion is provided around the opening of the recess, A washer magnet is disposed on the flange portion. The adapter for a lock bolt according to any one of claims 1 to 5.

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