JP6062280B2 - Anti-rust cap for lock bolt and anti-rust method for lock bolt head using anti-rust cap - Google Patents

Description

  The present invention relates to a rust prevention cap for a lock bolt that is buried in a natural ground or the like and protrudes from the surface of the rock bolt and covers a head of a lock bolt to which a nut is screwed, and a rust prevention cap for a lock bolt using the rust prevention cap. It relates to the rust method.

  As a conventional rust prevention method for the lock bolt, for example, a method of applying a rust preventive material by brushing or the like to the outer peripheral surface of the head of the lock bolt, or a method of using a lock bolt previously coated with a rust preventive material such as resin. is there. In addition, a rust prevention method has been proposed in which grease is applied to the head of a lock bolt and a heat-shrinkable film is applied to form a grease layer and a film layer (see, for example, Patent Document 1).

Japanese Patent No. 4173511

  However, the method of applying a rust preventive material to the head of the lock bolt with a brush or the like has a problem that it is necessary to dry the rust preventive material before screwing the nut, and the work process is delayed. In addition, in the method using a lock bolt coated with a rust preventive material in advance, when the nut is screwed into the head of the lock bolt and finally the torque is applied to tighten the nut, the coated rust preventive material is There exists a problem that it will peel off by a nut and the location which cannot anticipate the antirust effect in the head of a lock bolt will be made. This also causes the same problem in the method of applying a rust preventive material with a brush or the like.

  On the other hand, the rust prevention method for forming a grease layer and a film layer on the head of the rock bolt is to apply grease to the outer peripheral surface of the head corrosion prevention portion of the lock bolt with a brush or the like and cover the tube-shaped film having heat shrinkage. In order to protect the grease layer by closely contacting the lock bolt body by applying hot water to the film, etc., there is always a screw between the adjacent screw nodes. The tube-shaped film does not always adhere along the line. As a result, there is a portion where the grease flows and is not covered, and as a result, this method also has a problem that a portion where the antirust effect cannot be expected.

  Therefore, the present invention has been made paying attention to such problems, and the head can be covered with a rust preventive material without delaying the work process such as tightening of the head of the lock bolt. Even when the nut is screwed onto the head of the lock bolt covered with rust material or when the nut is finally tightened by applying torque, the rust-proof material is securely coated and the rust-proof effect cannot be expected. An object of the present invention is to provide a rust preventive cap for a lock bolt that prevents the occurrence of rust and a rust preventive method for the head of the lock bolt using the rust preventive cap.

In order to achieve the above object, a rust prevention cap for a lock bolt according to the present invention is a cylindrical rust prevention cap for a lock bolt that is embedded in a natural ground and covers a head of a lock bolt that protrudes from the surface of the rust prevention cap. A plurality of sealed spaces having a double structure of an outer film and at least an inner film which is more easily torn than the outer film, and which are bonded and partitioned at appropriate intervals between the outer film and the inner film. That the rust preventive material is enclosed in the sealed space corresponding to the screw joint surface formed on all of these sealed spaces or at least the peripheral surface of the lock bolt. Features.
Here, in the sealed space portion, it is preferable that the outer film and the inner film are bonded and partitioned along the boundary between the screw node surface and the plane alternately at least in the circumferential direction of the lock bolt.
Further, it is better that the rust preventive material is a resin having a property of hardening after the inner film is broken and flows out from the sealed space portion to the head of the lock bolt.
In the rust prevention method for a lock bolt head using the lock bolt rust prevention cap according to the present invention, the lock bolt head is covered with any of the lock bolt rust prevention caps described above, and the lock bolt By screwing a nut from the top of the anti-rust cap and tightening the nut last, at least the inner film of the anti-rust cap for the lock bolt is broken, and the anti-rust material enclosed in the sealed space is poured out and locked. It is characterized by rust-proofing the head of the bolt.
Here, the lock bolt is preferably such that at least its head is preliminarily coated with a rust preventive material sealed in a sealed space portion of the lock bolt rust preventive cap.

According to the rust preventive cap for lock bolts and the rust preventive method for the head of the lock bolt using the rust preventive cap according to the present invention, the outer film and the inner film are separated by being bonded and separated at appropriate intervals. A space portion is formed, and all of the sealed space portions or at least a sealed space portion corresponding to the screw joint surface of the lock bolt among the sealed space portions is sealed with a rust preventive material. When the nut is screwed from above, the inner film is torn at the last tightening, and the rust preventive material flows out from the sealed space to the entire head of the lock bolt. The work process can be shortened. Furthermore, even if the lock bolt is covered with a rust preventive material in advance, if the rust preventive cap for the lock bolt is put on the head and the nut is screwed together, the rust preventive material will move only within the sealed space. Since the rust preventive material accumulates at the end of the sealed space, the inner film is torn by tightening the nut and tightening the nut at the end, and at least flows out to the screw joint surface of the lock bolt. Since the rust preventive material that has flowed out is covered at the location where the rust preventive material that has been peeled off, the head of the lock bolt can be reliably rusted.
Also, since the lock bolt rust prevention cap has a cylindrical shape and the tip is closed, the lock bolt rust prevention cap is pushed against the nut even if it is screwed onto the lock bolt head. Since it is in a state where it is always put on the head of the lock bolt without sliding down, the rust prevention effect can be surely exhibited.

It is the front view, side view, top view, bottom view, and AA line expanded sectional view which shows an example of the antirust cap for lock bolts which concerns on this invention, respectively (a)-(e). It is sectional drawing which shows the state of the lock bolt embed | buried in the natural ground in the state which made the head protrude. It is sectional drawing which shows the state which covered the rust prevention cap for lock bolts on the head of the lock bolt protruded from the natural ground. It is sectional drawing which shows the state which screwed the nut through the anti-rust cap for lock bolts to the head of the lock bolt protruded from the natural ground. It is a partial expanded sectional view which shows the accumulation | storage state etc. of the rust preventive material at the time of screwing a nut in a lock bolt.

  Next, a rust prevention cap 1 for a lock bolt according to an embodiment of the present invention and a rust prevention method for the head of a lock bolt using the rust prevention cap 1 will be described with reference to the drawings.

  First, an antirust cap 1 for a lock bolt according to an embodiment of the present invention will be described with reference to FIG.

  The lock bolt anti-rust cap 1 according to the present invention is a cylinder (tube shape) that covers the head of the lock bolt 2 as shown in FIGS. It has a double structure of an outer film 11 and an inner film 12. The inner film 12 is easier to break than at least the outer film 11. A plurality of adhesive portions 13 are provided by adhering the outer film 11 and the inner film 12 at appropriate intervals, and the sealed spaces 1 a to 1 e partitioned by the adhesive portion 13 are provided.

  Here, the anticorrosion cap 1 for the lock bolt has a pair of flat surfaces 2b and 2d which are flush with a pair of screw node surfaces 2a and 2c provided with screw nodes in the longitudinal direction as shown in FIGS. Are placed on the heads of the lock bolts 2 made of threaded reinforcing bars provided alternately in the circumferential direction. Therefore, the adhesive portion 13 of the lock bolt anti-corrosion cap 1 is adhered along the boundary between the screw joint surfaces 2a, 2c and the flat surfaces 2b, 2d of the lock bolt 2, and sealed as shown in FIG. 1 (e). The sealed spaces 1a to 1e are provided so that the spaces 1a and 1c face the screw nodes 2a and 2c of the lock bolt 2. Moreover, in order to make the lock bolt antirust cap 1 into a cylindrical shape, either one of the left and right ends thereof is bonded to provide an adhesive portion 14. The lock bolt 2 may be either one whose surface is coated with a rust preventive material in advance, or one that is not covered, and is not particularly limited.

  And the rust preventive material 7 is enclosed with the sealed space part 1a, 1c which respectively opposes a pair of screw node surface 2a, 2c of the lock bolt 2 at least. In the case of the lock bolt 2 covered with the rust preventive material 8 as will be described later, the nut 6 is screwed onto the head of the lock bolt 2 and finally the torque is applied to tighten the nut 6. The screw ridges of the screw joint surfaces 2a and 2c of the lock bolt 2 and the screw grooves of the nut 6 are crushed and tightened to prevent the rust preventive material 8 covered with the screw joint surfaces 2a and 2c from being peeled off. This is for covering with the rust material 7. In addition, when the rust preventive material 8 is not coated, even when the nut 6 is finally tightened, the pre-coated rust preventive material 8 does not peel off, and the entire head of the lock bolt 2 is prevented. Since the rust preventive material 7 only needs to be covered with the rust material 7, the rust preventive material 7 is not only enclosed in the sealed space portions 1a and 1c facing the pair of screw node surfaces 2a and 2c of the lock bolt 2, respectively, but also in all the sealed spaces. It is better to enclose in the parts 1a to 1e. In addition, the length L in the longitudinal direction of the anti-rust cap 1 for the lock bolt is at least that of the female screw hole inside the nut 6 so that the screw joint surfaces 2a and 2c of the lock bolt 2 are reliably covered with the anti-rust material 7. It is desirable to make it approximately equal to the length (depth).

  The type of the rust preventive material 7 is not particularly limited, but the inner film 12 of the lock bolt rust preventive cap 1 is torn and flows out from the sealed spaces 1a and 1c to the head of the lock bolt 2 and then touches the air to be cured. A resin having characteristics is optimal, and for example, polyvinyl butyral resin (PVB) or epoxy resin is used. Moreover, since the rust prevention material 7 coat | covers the location where the rust prevention material 8 previously coat | covered by the lock bolt 2 was peeled, the same kind as the rust prevention material 8 is preferable.

  Any material may be used as the material of the outer film 11 and the inner film 12 of the lock bolt anti-corrosion cap 1 as long as the nut 6 cannot be broken until the nut 6 is finally tightened. It is preferable in terms of strength and cost. In addition, in order to make the inner film 12 easily torn before the outer film 11, a material having a small thickness or a material having a low strength may be used. As a result, when the nut 6 is screwed over the head of the lock bolt 2, it is sandwiched between the screw joint surfaces 2 a and 2 c of the lock bolt 2 and the screw groove of the nut 6 by the outer film 11. The inner film 12 is prevented from being torn even in the closed state, and when the nut 6 is finally tightened by applying torque, the screw groove of the nut 6 with the screw joint surfaces 2a and 2c is crushed. The inner film 12 is torn before the outer film 11 and flows out to the pair of screw node surfaces 2a and 2c of the lock bolt 2 instead of the thread groove of the nut 6, so that the rust preventive material 7 can be reliably coated. Even if the outer film 11 and the inner film 12 are made of the same material and the same thickness, when the nut 6 is finally tightened, both the films are torn at the same time, and the screw nodes 2a and 2c are covered with the rust preventive material 7. Therefore, it is sufficient that at least the outer film 11 is not torn before the inner film 12.

  Next, a rust prevention method for the lock bolt 2 using the lock bolt rust prevention cap 1 according to the present invention will be described. In this embodiment, as shown in FIG. 2, a pair of screw nodes 2a and 2c in the longitudinal direction and a pair of flat surfaces 2b and 2d that are flush with each other are provided in the circumferential direction. A method of using the lock bolt 2 having at least the head previously coated with the rust preventive material 8 will be described as an example.

  First, for example, the rock bolt 2 is inserted into a perforation 31 formed in the natural ground 3 as shown in FIG. 2, and is buried in the natural ground 3 by a grout material 32 injected into the periphery thereof.

  Therefore, the lock bolt anticorrosive cap 1 is placed on the head (projecting portion) of the lock bolt 2 protruding from the ground 3 as shown in FIG.

  At that time, since the lock bolt anticorrosion cap 1 according to the present invention has a cylindrical shape and the tip is closed, even if the nut 6 is screwed with the lock bolt 2 covered, the lock bolt Since the rust preventive cap 1 is not pushed down by the nut 6 and does not slide down, the rust preventive effect can be surely exhibited since it is covered with the head of the lock bolt 2. Further, the rust preventive material 7 sealed in the sealed space portions 1a and 1c of the lock bolt rust preventive cap 1 is made the same as the rust preventive material 8 coated on the head of the lock bolt 2 in advance. The head of the bolt 2 can be reliably covered.

  After that, as shown in FIG. 4, the head of the lock bolt 2 covered with the lock bolt anti-rust cap 1 is tightened by screwing the nut 6 through the bearing plate 4 and the washer 5.

  Here, since the screw bolts are used for the lock bolt 2, a space is formed between the pair of flat surfaces 2 b and 2 d that are flush with each other and the inner peripheral surface of the female screw hole of the nut 6. There is a backlash (interval) between the grooves. Accordingly, when the lock bolt rust prevention cap 1 is placed on the head of the lock bolt 2 and the nut 6 is screwed onto the lock bolt, the lock bolt rust prevention cap 1 enters the space or backlash (interval). And since the rust preventive material 7 enclosed in the sealed space portions 1a and 1c of the lock bolt rust preventive cap 1 is a fluid, a nut 6 is tightened on the lock bolt 2 as shown in FIG. Then, the screw joint surfaces 2a and 2c of the lock bolt 2 move toward one side by screwing with the thread groove of the nut 6. However, since the rust preventive material 7 is enclosed in the sealed space portions 1a and 1c that face the pair of screw nodes 2a and 2c of the lock bolt 2, respectively, the rust preventive material 7 faces the pair of flat surfaces 2b and 2d of the lock bolt 2, respectively. It does not move to the sealed space portions 1b, 1d, and 1e, and gathers around the adhesive portion 13 on one side of the sealed space portions 1a and 1c and collects as shown by the shaded portion 15 in FIG. Become.

  Finally, when the operator applies torque and firmly tightens the nut 6 to the lock bolt 2, the sealed space portion 1 a, between the screw node surfaces 2 a and 2 c of the lock bolt 2 and the screw groove of the nut 6, By crushing 1c, the part (shaded part 15 of FIG. 5) where the rust preventive material 7 accumulated is ruptured and the inner film 12 is torn.

  Then, the rust preventive material 7 collected and collected around the adhesive portion 13 in the sealed space portions 1a and 1c, and the rust preventive material dispersed in the sealed space portions 1a and 1c without being collected around the adhesive portion 13 7 flows out of the torn inner film 12 and covers the pair of screw nodes 2a, 2c of the lock bolt 2.

  And since the rust preventive material 7 has the peculiarity which hardens | cures in contact with air, when the coated rust preventive material 7 hardens | cures in those screwing parts and the nut 6 is fastened, the rust preventive material 8 peels off. The screw joint surfaces 2a and 2c that have been stuck are securely covered and rust-proof.

  In addition, the part which the antirust material 8 which was covered when the nut 6 was finally tightened by applying torque is shown as a problem of the prior art is mainly the screw node surfaces 2a and 2c of the lock bolt 2. 5 is a boundary portion from the root of the screw node to the screw thread, and a surface from the boundary portion to the screw thread (thick dotted line portion 16 in FIG. 5). However, since the rust preventive material 7 of this embodiment has a characteristic of flowing out from the lock bolt rust preventive cap 1 and touching the air to be cured, the thick dotted line portion 16 from which the rust preventive material 8 is peeled is also inside. At the same time as the film 12 is torn, the rust preventive material 7 is coated. Therefore, even if it is a part in which the rust preventive material 8 is easy to peel in the prior art, according to the rust preventive cap 1 for lock bolts of the present invention, it can be reliably covered and rust prevented.

  As described above, according to the rust prevention cap 1 for the lock bolt and the rust prevention method for the head of the lock bolt 2 using the rust prevention cap 1, the outer film 11 and the rust prevention cap 1 for the lock bolt are provided. Sealed space portions 1a to 1e that are bonded and partitioned at appropriate intervals are formed between the inner films 12, and at least screw thread surfaces 2a and 2c of the lock bolt 2 among the sealed space portions 1a to 1e. Since the rust preventive material 7 is enclosed in the corresponding sealed spaces 1a and 1c, the nut 6 is screwed onto the head of the lock bolt 2 and the nut 6 is finally tightened by applying torque. The film 12 is torn and flows out to the screw joint surfaces 2a and 2c of the lock bolt 2 so that the rust preventive material 7 is surely covered in a place where the rust preventive material 8 previously coated at the time of tightening is peeled off. It is possible to rust. Further, the head of the lock bolt 2 can be easily covered without using a brush or the like without applying the rust preventive material 7.

  In addition, since the lock bolt rust prevention cap 1 has a cylindrical shape and the tip is closed, even if the nut 6 is screwed with the lock bolt 2 covered, the lock bolt rust prevention cap 1 is used. Since 1 is not pushed down by the nut 6 and is always covered with the head of the lock bolt 2, the inner film 12 is torn at the place where the rust preventive material 7 should be covered, and the lock bolt The rust preventive material 7 can be reliably coated on the two screw node surfaces 2a and 2c to exert the rust preventive effect.

  Further, as the rust preventive material 7, polyvinyl butyral resin (PVB), epoxy resin, or the like having a characteristic of being cured by touching air after flowing out from the sealed space portions 1a and 1c to the head of the lock bolt 2 is used. Therefore, at least the screw node surfaces 2a and 2c of the head of the lock bolt 2 can be reliably covered and rust-proof.

  In the description of the above embodiment, as the lock bolt 2, a screw joint reinforcing bar in which a pair of screw joint surfaces 2 a and 2 c and a pair of flat surfaces 2 b and 2 d that are flush with each other is provided in the circumferential direction is taken as an example. However, in the present invention, the present invention is not limited to this, and it is also applicable to a threaded bar rebar in which a threaded joint is formed over the entire outer peripheral surface. In this case, the rust preventive material 7 is sealed in all the sealed spaces 1a to 1e of the lock bolt rust preventive cap 1.

  In the above-described embodiment, an example in which the head of the newly installed lock bolt 2 is covered with the lock bolt anticorrosion cap 1 and the nut 6 is tightened from above is described, but the head of the existing lock bolt 2 is described. The present invention can also be applied to the part. In this case, the nut 6 that has already been tightened is removed to expose the head of the lock bolt 2, and the anti-rust cap 1 for the lock bolt of the present invention is placed on the head, and the nut is removed again. 6 may be tightened.

  DESCRIPTION OF SYMBOLS 1 ... Rust prevention cap for lock bolts, 1a-1e ... Sealed space part, 11 ... Outer film, 12 ... Inner film, 13, 14 ... Adhesion part, 2 ... Lock bolt, 2a, 2c ... Screw node surface, 2b, 2d ... Plane, 3 ... Ground, 31 ... Perforation, 32 ... Grout material, 4 ... Bearing plate, 5 ... Washer, 6 ... Nut, 7, 8 ... Rust prevention material.

Claims (5)

  It is a rust prevention cap for a lock bolt that is covered with a head of a lock bolt that is embedded in a natural ground and protrudes from the surface, and whose tip is closed, and includes an outer film and at least an inner film that is more easily torn than the outer film. A sealed structure having a double structure and bonded and partitioned at an appropriate interval is formed between the outer film and the inner film, and all of the sealed spaces or all of the sealed spaces are formed. A rust preventive cap for a lock bolt, wherein a rust preventive material is sealed in a sealed space portion corresponding to a screw node formed on at least a peripheral surface of the lock bolt. In the rust prevention cap for lock bolts of Claim 1,
The sealed space portion is characterized in that the outer film and the inner film are bonded and partitioned along a boundary portion between a screw node surface and a plane that are alternately provided in the circumferential direction of the lock bolt at least. Rust prevention cap for bolts. In the rust prevention cap for lock bolts of Claim 1 or Claim 2,
A rust preventive cap for a lock bolt, characterized in that the rust preventive material is a resin having a property of being hardened after the inner film is torn and flows from the sealed space to the head of the lock bolt.   The head of the lock bolt is covered with the anti-rust cap for the lock bolt according to any one of claims 1 to 3, and the nut is screwed onto the anti-rust cap for the lock bolt. By tightening at the end, it breaks at least the inner film of the anti-rust cap for the lock bolt, and the anti-rust material sealed in the sealed space is allowed to flow out to prevent the head of the lock bolt from rusting. Rust prevention method for the head. In the rust prevention method of the head of the lock bolt according to claim 4,
A rust prevention method for a head of a lock bolt, wherein the rust prevention material sealed in a sealed space portion of the rust prevention cap for the lock bolt is coated in advance at least on the head of the lock bolt.

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