JP7378325B2 - One-touch lock bolt - Google Patents

Description

The present invention relates to a one-touch locking bolt suitable for use in tunnel construction and the like.

For example, in a mountain tunnel excavated by the NATM construction method, as shown in FIG. 4(A), concrete C1 is sprayed onto the inner surface 50 of the ground formed by excavating the ground.
Thereafter, holes 52 are drilled into the inner surface 50 of the rock from above the hardened concrete C1 at multiple locations spaced apart in the circumferential and longitudinal directions of the tunnel, and a fixing material such as mortar is injected into each hole 52. Ru.
Then, a lock bolt 54 is inserted into each hole 52, and the base of the lock bolt 54 protruding from the concrete C1 is inserted into the center hole 5602 of a steel bearing plate 56 made of a square plate or a round plate. The bearing plate 56 is pressed against the surface of the concrete C1, the nut 58 is screwed onto the male thread at the base of the rock bolt 54, and the nut 58 is tightened to press the bearing plate 56 against the surface of the concrete C1. The installation work has been completed and the rock is being fixed.
After that, as shown in Fig. 4(B), a waterproof sheet is laid on the inner surface of the concrete C1 to prevent water from the ground from entering the tunnel, and the concrete is placed opposite to this waterproof sheet. A frame is placed, and concrete C2 is poured between the waterproof sheet and the formwork surface of the concrete pouring formwork to perform lining concrete.

Japanese Patent Application Publication No. 2019-167774

On the other hand, in shoring, the work of screwing the nut 58 onto the male thread at the base of the rock bolt 54 and rotating the nut 58 to press the bearing plate 56 against the surface of the concrete C1 is performed by a worker on a scaffold. This often results in an awkward posture, making it a time-consuming task.
Furthermore, since the work involves rotating the nut 58, it is time consuming and requires being near the bedrock onto which the concrete C1 has been sprayed for a long time, making the work accompanied by danger.
In particular, when the tunnel cross section is large and the tunnel length is large, the number of lock bolts 54 becomes thousands or tens of thousands, and the work of tightening the nuts 58 takes a lot of time and increases the danger. Some kind of improvement was desired from the perspective of shortening the construction period of tunnel construction and reducing costs.
The present invention was developed in view of the above circumstances, and its purpose is to omit the work of tightening nuts and to press the bearing plate onto the concrete surface with one touch, which is advantageous in reducing danger. An object of the present invention is to provide a one-touch fixing type lock bolt which is advantageous in shortening the construction period of tunnel construction and reducing costs, and is suitable for use in tunnel construction.

In order to achieve the above object, the present invention provides a one-touch lock bolt, the one-touch lock bolt comprising a lock bolt body and a cylindrical lock member into which the lock bolt body is inserted. , the locking member is configured to include a hollow elastic hollow body made of an elastic material and extending in an annular shape and having a housing space therein, and a magnetic fluid sealed in the housing space; When a magnet is brought close to the body, the magnetic fluid spreads outward in the radial direction of the elastic hollow body due to the magnetic force of the magnet, and the inner diameter of the inner peripheral surface of the hollow body becomes larger than the outer diameter of the lock bolt body, and When the magnet is released, the elastic hollow body contracts radially inward, and the inner diameter of the inner circumferential surface of the hollow body becomes smaller than the outer diameter of the lock bolt body, so that the inner circumferential surface is pressed against the outer circumferential surface of the rock bolt body. It is characterized by being
Further, the present invention provides that the length of the elastic hollow body along the axial direction is larger than the outer diameter of the elastic hollow body when the magnet is separated from the locking member. Features.
Further, the present invention is characterized in that the elastic material constituting the elastic hollow body is rubber.
Further, the present invention is characterized in that the magnetic fluid is composed of a colloidal liquid in which fine magnetic particles are dispersed in a dispersion medium.

According to the one-touch fixing type lock bolt of the present invention, for example, if a glove with a magnet sewn onto the finger is prepared and the lock member is grabbed with the glove, the magnetic fluid is attracted by the magnetic force of the magnet, and the elastic hollow body is The inner peripheral surface expands. Then, while holding the lock member with the glove, the lock bolt body is inserted through the inner peripheral surface of the lock member, and the glove is released from the lock member. When the glove is released from the locking member, the magnetic force no longer acts on the magnetic fluid, so the elastic hollow body contracts radially inward, and the inner circumferential surface of the elastic hollow body is pressed against the outer circumferential surface of the lock bolt body.
Therefore, when lock bolting is used for tunnel shoring, the conventional time-consuming work of rotating nuts can be omitted, and the lock member can be moved along the bolt body, pressed against the bearing plate, and released with a single touch. This is advantageous in increasing the efficiency of bolt installation work.
In addition, since the rock bolt installation work can be done in a short time, during tunnel shoring work, it is only necessary to be near the bedrock onto which concrete has been sprayed for a short time, which is advantageous in reducing danger.
In addition, since the ground can be supported in a short time, it is advantageous in stabilizing the ground quickly.
In particular, according to the one-touch lock bolt of the present invention, even when the tunnel cross section is large, the tunnel length is large, and the number of rock bolts is in the thousands or tens of thousands, the lock bolt can be installed easily. The time required for work can be significantly shortened, which is advantageous in shortening the construction period of tunnel construction and reducing costs.
Furthermore, even if a deformed reinforcing bar with an uneven shape on the outer periphery is used for the lock bolt, the lock member is configured to include an elastic hollow body made of an elastic material that can be elastically deformed. The locking member deforms to follow the uneven shape of the surface of the deformed reinforcing bar, etc., and is securely pressed against the outer periphery, which is advantageous for securely attaching the locking member so that it cannot move in the longitudinal direction of the lock bolt body. becomes.
In addition, since the lock member is attached to the lock bolt body by reducing the diameter of the center hole, there is no need to form a male thread on the lock bolt body as in the past, and reinforcing bars can be used as is, reducing costs for tunnel construction etc. It will be advantageous above.
In addition, in the one-touch locking bolt of the present invention, if the length along the axial direction of the elastic hollow body is made larger than the outer diameter of the elastic hollow body, the locking member can be easily grasped, and the locking member can be easily grasped. This is advantageous in improving the operability of the member and making the lock bolt installation work easier.
In addition, in the one-touch lock bolt of the present invention, when rubber is used as the elastic material constituting the elastic hollow body, the rubber has a large coefficient of friction against the lock bolt body, so it is locked to the rock bolt body in a manner that it cannot move in the longitudinal direction. This is advantageous in attaching members reliably.
In addition, in the one-touch fixing type lock bolt of the present invention, if magnetite is used as the magnetic particles constituting the magnetic fluid sealed in the accommodation space of the elastic hollow body, the lock member can be manufactured easily because it can be easily obtained at low cost. This is advantageous in reducing the cost of rock bolts.

(A) is a front view of the lock member with no magnetic force acting on it, (B) is a cross-sectional side view of the same, (C) is a front view of the lock member with magnetic force acting on it, and (D) is the same side view. FIG. 3 is a cross-sectional side view. (A) is a diagram showing a state in which the lock bolt body is inserted into the lock member, and (B) is a diagram showing a state in which the lock member is immovably attached to the lock bolt body. It is an explanatory view of shoring using the one-touch lock bolt of this embodiment. In the explanatory diagrams of the conventional construction method, (A) is an explanatory diagram of shoring, and (B) is an explanatory diagram of lining concrete.

Next, embodiments of the present invention will be described with reference to the drawings.
Note that the same reference numerals are given to conventional parts and members, and the explanation thereof will be omitted.
As shown in FIG. 3, the one-touch fixing type rock bolt 10 includes a rock bolt main body 14 inserted into a hole 52 drilled into the inner surface 50 of the earth from above the concrete C1, and a lock protruding into the tunnel from the concrete C1. The locking member 16 is coupled to the base 1402 of the bolt body 14.
Note that one end of the lock bolt body 14 in the longitudinal direction is called a tip 1401, and the other end is called a base 1402.
The lock bolt main body 14 is made of steel, and a deformed reinforcing bar or a round bar reinforcing bar is used for the rock bolt main body 14, and in this embodiment, a different diameter reinforcing bar is used.

As shown in FIG. 2, the locking member 16 includes an elastic hollow body 18 and a magnetic fluid 20.
The elastic hollow body 18 is made of an elastic material, has a housing space 1802 therein, extends in an annular shape, and has a hollow cylindrical shape with a central hole 1804 passing through its center.
As shown in FIG. 1(B), the length L of the elastic hollow body 18 along the axial direction is larger than the outer diameter D of the elastic hollow body 18.
Various conventionally known materials can be used as such elastic materials, but since rubber has a large coefficient of friction against the lock bolt body 14, it is difficult to securely attach it to the rock bolt body 14 in a manner that it cannot move in the longitudinal direction. It is advantageous.

The magnetic fluid 20 is enclosed in the housing space 1802.
The magnetic fluid 20 is a magnetic liquid, and has the property of being attracted to a magnet by its magnetic force when a magnet is brought close to it.
The magnetic fluid 20 is composed of a colloidal liquid in which fine magnetic particles having a particle size of about 100 to 200 angstroms are stably dispersed in a dispersion medium such as water or mineral oil. As such magnetic particles, conventionally known magnetic particles such as magnetite and manganese zinc ferrite can be used.
Using magnetite is advantageous in terms of availability and cost.
In this embodiment, the locking member 16 has a center hole 1804 whose inner diameter is larger than the outer diameter of the lock bolt body 14, as shown in FIGS. The inner peripheral surface of the center hole 1804 is also formed to be in pressure contact with the outer peripheral surface of the lock bolt body 14.
Furthermore, when a magnetic force is applied to the magnetic fluid 20 as shown in FIGS. is formed to have a larger dimension than the outer diameter of the lock bolt body 14.

Next, tunnel construction using the one-touch lock bolt 10 of this embodiment will be described.
First, when using the one-touch fixing type lock bolt 10 of this embodiment, as shown in FIGS. 2(A) and 3, gloves 34 having thin plate-shaped magnets 32 sewn into the fingertips are prepared. .
As in the conventional case, as shown in FIG. 3, tunnel shoring is performed by spraying concrete C1 onto the inner surface 50 of the earth formed by excavating the earth, and the tunnel is supported at intervals in the circumferential and longitudinal directions of the tunnel. Holes 52 are drilled into the ground from above the semi-hardened concrete C1 at a plurality of locations, and a fixing material such as mortar is injected into each hole 52.
Next, the rock bolt body 14 is inserted into each hole 52 from above the concrete C1, and then the base 1402 of the rock bolt body 14 is inserted into the center hole 5602 of the bearing plate 56, and the bearing plate 56 is locked into a one-touch fixed lock. Located at the base 1402 of the bolt 10.

Once the bearing plate 56 is in place, grasp the locking member 16 with the glove 34.
When the locking member 16 is grasped with the glove 34, the magnetic force of the magnet 32 acts on the magnetic fluid 20, and the magnetic fluid 20 spreads outward in the radial direction of the elastic hollow body 18 and forms the center hole 1804, as shown in FIG. 2(A). The inner diameter is larger than the outer diameter of the lock bolt body 14.
Then, while grasping the lock member 16 with the gloves 34, insert the base 1402 of the lock bolt main body 14 into the center hole 1804, move the lock member 16 toward the front end 1401 of the lock bolt, and move the lock member 16 to the bearing plate. 56 and press the bearing plate 56 against the concrete C1 via the locking member 16, the glove 34 is released from the locking member 16.
When the glove 34 is removed from the lock member 16, no magnetic force acts on the magnetic fluid 20, and as shown in FIG. 2(B), the inner diameter of the center hole 1804 becomes smaller than the outer diameter of the lock bolt body 14. The inner peripheral surface of the center hole 1804 is pressed against the outer peripheral surface of the rock bolt body 14, and the lock member 16 is immovably attached to the base of the rock bolt body 14 with the bearing plate 56 pressed against the concrete C1. .

Therefore, according to the one-touch lock bolt 10 of the present embodiment, the one-touch operation is simply to move the lock member 16 along the base 1402 toward the tip 1401 of the lock bolt body 14, press it against the bearing plate 56, and release it. Therefore, it is possible to press the bearing plate 56 against the surface of the concrete C1 in a shorter time than the conventional work of screwing the nut 58 onto the male thread at the base of the lock bolt 54 and rotating the nut 58. This is advantageous in increasing the efficiency of rock bolt installation work.
Furthermore, since the rock bolt installation work can be carried out in a short time, it is sufficient to stay near the rock mass onto which the concrete C1 has been sprayed for a short time, which is advantageous in reducing danger.
In addition, since the ground can be supported in a short time, it is advantageous in stabilizing the ground quickly.
In particular, according to the one-touch fixing type lock bolt 10 of the present embodiment, even when the tunnel cross section is large, the tunnel length is large, and the number of lock bolts is in the thousands or tens of thousands, it is possible to lock the lock bolt. The time required for bolt installation work can be significantly shortened, which is advantageous in shortening the construction period of tunnel construction and reducing costs.
Furthermore, even when a deformed reinforcing bar having an uneven shape on the outer periphery is used for the lock bolt main body 14, the lock member 16 is configured to include an elastic hollow body 18 made of an elastic material that can be elastically deformed. As a result, the locking member 16 deforms to follow the uneven shape of the surface of the deformed reinforcing bar, etc., and is securely pressed against the outer periphery, so that the locking member 16 is reliably immovable in the longitudinal direction of the lock bolt body 14. This is advantageous when attaching to the
In addition, since the lock member 16 is attached to the lock bolt body 14 by reducing the diameter of the center hole 1804, there is no need to form a male thread in the lock bolt body 14 as in the past, and reinforcing bars, steel rods, etc. can be used as they are, and the tunnel This is advantageous in reducing construction costs.

Furthermore, according to the one-touch locking bolt 10 of the present embodiment, the length L of the elastic hollow body 18 along the axial direction is larger than the outer diameter D of the elastic hollow body 18. This makes it easier to grip the locking member 16, improving the operability of the locking member 16, and is advantageous in making the lock bolt installation work easier.
Further, when rubber is used as the elastic material constituting the elastic hollow body 18, since rubber has a large coefficient of friction against the lock bolt body 14, it is possible to securely attach the lock member 16 to the lock bolt body 14 without moving in the longitudinal direction. It is advantageous.
In addition, if magnetite is used as the magnetic particles constituting the magnetic fluid 20 sealed in the accommodation space 1802 of the elastic hollow body 18, the locking member 16 can be easily manufactured because it can be easily obtained at a low price. This is advantageous in reducing costs.

In addition, in this embodiment, the case where the one-touch locking type lock bolt 10 is used for tunnel construction has been described, but the use of the one-touch locking type lock bolt 10 is not limited to tunnel construction, but can be applied to various conventionally known uses. be done.

10 One-touch fixing lock bolt 14 Lock bolt main body 1401 Tip 1402 Base 16 Lock member 18 Elastic hollow body 1802 Accommodation space 1804 Center hole 20 Magnetic fluid 32 Magnet 34 Glove 50 Earth's inner surface 52 Hole 54 Lock bolt 56 Bearing plate 5602 Center hole 58 Nut

Claims (3)

A one-touch locking bolt used for tunnel construction ,
The one-touch lock bolt includes a lock bolt body and a cylindrical lock member into which the lock bolt body is inserted,
The locking member includes a cylindrical elastic hollow body made of an elastic material, having a housing space therein, extending in an annular shape, and having a central hole penetrated through the center thereof, and a magnetic fluid sealed in the housing space. Consisting of
When a magnet is brought close to the locking member from both sides of the elastic hollow body in the diametrical direction so as to sandwich the elastic hollow body, the magnetic fluid spreads outward in the radial direction of the elastic hollow body due to the magnetic force of the magnet, increasing the inner diameter of the center hole. is larger than the outer diameter of the lock bolt main body, and when the magnets are separated from both sides of the elastic hollow body in the diametrical direction, the elastic hollow body contracts radially inward and the inner diameter of the center hole becomes larger than the outer diameter of the lock bolt body. The dimensions are smaller than the outer diameter of the main body,
The lock bolt body is inserted into the center hole of the elastic hollow body with the inner diameter of the center hole being larger than the outer diameter of the lock bolt body, and the magnet is inserted from both sides of the elastic hollow body in the diametrical direction. When released, the inner circumferential surface of the center hole is pressed against the outer circumferential surface of the lock bolt body;
A one-touch locking bolt that is characterized by: the elastic material constituting the elastic hollow body is rubber;
The one-touch locking bolt according to claim 1 , characterized in that: The magnetic fluid is composed of a colloidal liquid in which magnetic fine particles are dispersed in a dispersion medium.
The one-touch lock bolt according to claim 1 or 2 , characterized in that:

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