Hexagonal bolt co-rotation prevention fitting for pipe bands

Abstract

To provide a metal fitting for preventing corotation capable of reliably preventing corotation and fastening a fastening nut without labor while it is difficult to deform, even when large fastening torque is applied to a head corner part of a hexagonal head bolt due to usage of an electric driver and the like, in an operation for fastening the fastening nut of a piping band.SOLUTION: A corotation preventing metal fitting prevents a hexagonal head bolt from corotating with a fastening nut for fastening a piping by fastening a band wound around an outer periphery of the piping. A metal fitting body is constituted by a stationary piece provided with a through hole fitted with a head side face of the hexagonal head bolt, and an engagement piece engaged with the fastening piece of the band. An inner edge of the through hole is formed on an outer side than a virtual circumscription circle along the head corner part of the hexagonal head bolt, and a rotation prevention piece with a tip end projecting to an inner side than the virtual circumscription circle is formed from the inner edge toward the head side face of the hexagonal head bolt.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a co-rotation prevention fitting that prevents a hexagonal bolt from rotating together with a piping band when a clamping nut is tightened, when attaching a piping to a piping band. [Background technology]

[0002] Conventionally, to prevent the hexagonal bolt of a piping band from rotating together, a convex rib is cut and raised along the opposite side of the head side of the hexagonal bolt near the through hole of the fastening piece into which the hexagonal bolt is inserted, and the head side of the hexagonal bolt abuts against the rib to prevent the bolt from rotating together (see Figure 10).

[0003] Patent Document 1 also shows a roughly U-shaped metal fitting having a fixing piece with a hexagonal hole that fits into the side of the head of a hexagonal bolt, an engaging piece with an engaging groove at its tip that engages with the threaded portion of the hexagonal bolt, and a locking piece that connects these pieces facing each other and locks onto the edge of the fastening piece of the band, and the hole is hexagonal and slightly larger than the head of the hexagonal bolt, or a raised piece is formed on the opposite side of the head, against which the head is abutted, and the locking piece abuts against the edge of the fastening piece of the piping band to obtain a reaction force, thereby preventing the bolt from rotating. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-3014 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a convex rib is formed by cutting into the fastening piece of the piping band itself as in the above-mentioned conventional example, a defect is formed in the cross section of the fastening piece that bears the load of the piping to be fixed, which reduces the tensile strength that bears the load of the piping, and in some cases this configuration cannot be adopted for piping that is heavy. In Patent Document 1, instead of processing part of the band, a separate metal fitting is used, which solves the problem of reduced strength seen in the conventional example. However, when tightening the clamping nut, there is a risk that the corner of the head of the hexagonal bolt will come into contact with the inner edge of the through hole and become deformed. In other words, taking into consideration the attachment of a separate metal fitting, the through hole of the fixing piece is formed slightly larger than the head of the hexagonal bolt, and therefore a slight gap is created between the head of the hexagonal bolt and the through hole. However, when the clamping nut is tightened, this slight gap causes the hexagonal bolt to rotate slightly together with the bolt, causing the corner of the head to come into linear contact with the inner edge of the through hole. When tightening nuts, electric rotating tools such as electric screwdrivers may be used, many of which are high-powered, and a large tightening torque is transmitted to the corner of the head, which comes into linear contact and causes stress to be concentrated due to the rotation of the hexagonal bolt, resulting in deformation of the inner edge of the through hole. Furthermore, if the deformation becomes excessive, the function of preventing co-rotation may be lost.

[0006] The present invention has been made in consideration of the above-mentioned problems in the conventional art, and has an object to provide a co-rotation prevention fitting which is less likely to deform, reliably prevents co-rotation, and allows for hassle-free tightening of the tightening nut, even if a large tightening torque is applied to the head corner of a hexagonal bolt using an electric screwdriver or the like when tightening a tightening nut for a piping band. [Means for solving the problem]

[0007] The first configuration is a co-rotation prevention fitting that prevents a hexagonal bolt from rotating together with a tightening nut that fixes the piping by tightening a band wrapped around the outer periphery of the piping, and in the fitting body that is composed of a fixing piece with a through hole that fits into the head side of the hexagonal bolt and a locking piece that locks onto the tightening piece of the band, the inner edge of the through hole is formed outside an imaginary circumscribing circle that follows the head corner of the hexagonal bolt, and the tip surface protrudes inward from the imaginary circumscribing circle toward the head side of the hexagonal bolt from the inner edge. The side of the head of the hexagonal bolt comes into contact with the surface. It is characterized by the formation of a rotation prevention piece.

[0008] The second configuration is characterized in that, in addition to the first configuration, anti-rotation pieces are formed at two or more opposing positions on the side surface of the head of the hexagonal bolt.

[0009] The third configuration is characterized in that, in addition to the first or second configuration, the locking piece is locked to one or both end edges of the fastening piece of the band, and the metal fitting body is formed into an approximately L-shape or an approximately U-shape.

[0010] The fourth configuration is characterized in that, in addition to the first or second configuration, an engagement piece extending from one of the locking pieces and provided with an engagement portion that engages with the threaded portion of the hexagonal bolt is formed opposite the fixed piece. Effect of the Invention

[0011] According to the first configuration, in a metal fitting body composed of a fixed piece with a through hole that fits into the head side of a hexagonal bolt, and a locking piece that locks into the fastening piece of the band, the inner edge of the through hole is formed outside an imaginary circumscribing circle that follows the head corner of the hexagonal bolt, and an anti-rotation piece is formed whose tip surface protrudes inward from the imaginary circumscribing circle toward the head side of the hexagonal bolt from the inner edge.As a result, when the tightening nut is tightened, there is a clearance gap between the inner edge of the through hole and the head of the hexagonal bolt, so that the hexagonal bolt rotates slightly and the head side of the hexagonal bolt comes into contact with the anti-rotation piece protruding from the inner edge of the through hole. In other words, by having the side surface of the head of the hexagonal bolt come into planar contact with the anti-rotation piece protruding from the inner edge of the through hole, the stress caused by the rotation of the hexagonal bolt is dispersed more than if the corner of the head of the hexagonal bolt were to come into linear contact, and as a result, the stress acting on the inner edge of the through hole (anti-rotation piece) is reduced, making it possible to suppress deformation (see Figure 9).

[0012] According to the second configuration, by forming anti-rotation pieces in two or more opposing locations on the head side of the hexagonal bolt, the number of points of planar contact between the head side of the hexagonal bolt and the inner edge of the through hole of the fixing piece (anti-rotation piece) increases, and the stress transmitted to the inner edge of the through hole of the fixing piece (anti-rotation piece) can be distributed, making it possible to more reliably suppress deformation.

[0013] According to the third configuration, the locking piece is locked to one or both end edges of the fastening piece of the band, and the metal fitting body is formed into an approximately L-shape or an approximately U-shape, so that the metal fitting body can be easily attached to the fastening piece of the band. It is characterized by:

[0014] According to the fourth configuration, an engaging piece extending from one side of the locking piece and provided with an engaging portion that engages with the threaded portion of the hexagonal bolt is formed opposite the fixed piece. This allows the overlapping portion of the fastening piece of the band and the mounting piece of the turnbuckle to be clamped between the fixed piece of the metal fitting body and the engaging piece, and the engaging portion of the engaging piece is engaged with the threaded portion. When the fastening nut screwed onto the hexagonal bolt is removed when attaching the piping to the band, the engaging piece acts as a stopper to prevent the band and turnbuckle from falling off the hexagonal bolt, and the band and turnbuckle become one unit, making it easier to install the piping. [Brief description of the drawings]

[0015] [Figure 1] FIG. [Diagram 2] FIG. 13 is a perspective view of the anti-rotation fitting from a different angle. [Diagram 3] FIG. [Figure 4] FIG. 13 is a perspective view showing another embodiment of the metal fitting body. [Diagram 5] FIG. 11 is a plan view showing another embodiment of the through hole; [Figure 6] FIG. 13 is a perspective view showing the use of an anti-rotation fitting. [Figure 7] FIG. 13 is a perspective view showing the use of an anti-rotation fitting. [Figure 8]FIG. 13 is a perspective view showing a state in which another embodiment of the metal fitting body is used; [Figure 9] FIG. 13 is a comparison diagram of (a) the through hole of the anti-rotation fitting and (b) the hexagonal through hole of a conventional example. [Figure 10] A conventional example in which a convex rib is formed on the fastening piece of the band. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The co-rotation prevention fitting according to this embodiment will be described with reference to FIGS. Reference numeral 1 denotes a metal fitting body, in which a flat fixed piece 10 and an engaging piece 20 face each other, and ends of the fixed piece 10 and the engaging piece 20 are connected by a locking piece 30 to form a roughly U-shape in plan view. The fixing piece 10 is provided with a through hole 11 through which the head of the hexagonal bolt A can be inserted. The head of the hexagonal bolt A is a hexagonal column formed of six head corners A1 and six head side surfaces A2. The through hole 11 is generally cross-shaped with a width greater in the vertical direction than in the horizontal direction. When a virtual circle having a center at the same position as the hexagonal bolt A through hole 11 and extending along the six head corners A1 of the hexagonal bolt A is taken as a virtual circumscribing circle X, inner edge portions 12 are formed outside the virtual circumscribing circle X at two upper and lower points of the head side surface A2 of the hexagonal bolt A and two left and right points of the head corners A1, and anti-rotation pieces 13 are formed toward the four opposing points of the head side surface A2 of the hexagonal bolt A so that the tip surface is inward from the virtual circumscribing circle X. The through hole 11 is generally cross-shaped and is formed by the inner edge portion 12 and the anti-rotation piece 13. When a hexagonal bolt A is inserted into the through hole 11, it abuts against the anti-rotation pieces 13 at four of the six head side surfaces A2, and the other two of the head side surfaces A2 and the six head corners A1 have clearance between them and the inner edge portion 13. It is desirable that the tip surface of the rotation prevention piece 13 be a surface approximately parallel to the head side surface A2 of the hexagonal bolt A so as to come into planar contact with the head side surface A2. The engaging piece 20 is formed by bending one end of the fixed piece 10 to form a locking piece 30, and the other end of the locking piece 30 is bent and extended so as to face the fixed piece 10. At the tip of the engagement piece 20, a groove-like engagement portion 21 formed with a width that can engage with the root portion of the threaded portion A3 of the hexagonal bolt A is provided. The engagement portion 21 is engaged with the threaded portion A3 so as to have the strength to prevent the band B and the turnbuckle B1 from falling off the hexagonal bolt A when the fastening nut A4 screwed onto the hexagonal bolt A is removed. The engaging portion 21 may be a through hole, and it is sufficient if it can engage with the threaded portion A3 of the hexagonal bolt A and provide the temporary fastening effect. The locking piece 30 is the connecting part between the fixed piece 10 and the engaging piece 20, and it is preferable that its width is slightly wider than the thickness where the fastening piece B2 of the band B and the mounting piece B3 of the turnbuckle B1 overlap. The rotational force transmitted to the through hole 11 of the fixed piece 10 as the hexagonal bolt A rotates together comes into contact with the side of the fastening piece B2 of the band B, creating a reaction force, thereby preventing rotation. The metal fitting body constructed as described above is preferably integrally formed by pressing a thin steel plate, but is not limited to this.

[0017] 4-5 show another embodiment. In Figs. 4 and 5, the same members as those in the above embodiment are denoted by the same reference numerals, and some of the descriptions thereof will be omitted. FIG. 4(a) shows a metal fitting body having a generally L-shaped configuration in plan view, which is composed of a fixed piece 10 and a locking piece 30 formed by bending one end of the fixed piece 10, and FIG. 4(b) shows a metal fitting body having a generally U-shaped configuration in plan view, which is composed of a fixed piece 10 and locking pieces 30, 30 formed by bending both ends of the fixed piece 10, both of which can be attached by locking to the end of the fastening piece B2 of the band B.

[0018] FIG. 5 shows another embodiment of the through hole 11. In the above embodiment, the anti-rotation pieces 13 are formed at four opposing locations on the side of the head of the hexagonal bolt, but it is also possible to form them at two (a), three (b), or six (c) locations.

[0019] A method for using the co-rotation prevention fitting configured as above will be described with reference to FIGS. The piping band has fastening pieces B2 with insertion holes for hexagonal bolts A on both ends, an arc-shaped band B that is wrapped around the outer circumference of piping D and attached, and a connecting nut B4 that is screwed onto a hanging bolt C. A turnbuckle B1 is made up of an attachment piece B3 with an insertion hole for the hexagonal bolt A on the bottom, and is connected by inserting the hexagonal bolt A into the insertion holes of both the fastening piece B2 and the attachment piece B3 with the fastening piece B2 and the attachment piece B3 overlapping each other and screwing the fastening nut A4 into the threaded portion A3. The metal fitting body 1 is inserted so that the overlapping portion of the fastening piece B2 of the band B and the mounting piece B3 of the turnbuckle B1 is sandwiched between the fixed piece 10 and the engaging piece 20, and the through hole 11 of the fixed piece 10 is fitted onto the head of the hexagonal bolt A arranged on the outside of the fastening piece B2 of the band B, and the groove-shaped engaging portion 21 of the engaging piece 20 is engaged with the threaded portion A3 of the hexagonal bolt A in advance. After screwing the connecting nut B4 of the turnbuckle B1 onto the hanging bolt C suspended below the floor, the tightening nut A4 is removed, one side of the band B is opened, and the tightening nut A4 is screwed onto the hexagonal bolt A and tightened to secure it. At that time, the tightening torque that rotates the tightening nut A4 is transmitted to the hexagonal bolt A, which rotates slightly in the gap between the inner edge 12 of the through hole 11 and the head of the hexagonal bolt, causing the head side A2 of the hexagonal bolt A to abut against the anti-rotation piece 13 protruding from the inner edge 12 of the through hole 11, preventing the hexagonal bolt A from rotating together. By having the two parts come into contact with each other in a planar manner, the stress caused by the rotation of the hexagonal bolt is dispersed, reducing the stress acting on the rotation prevention piece of the through hole, thereby suppressing deformation.

[0020] FIG. 8 shows the state in which the metal fitting body 1 shown as the other embodiment is attached to a band B in a shape that is approximately L-shaped in a plan view (a) and a shape that is approximately U-shaped in a plan view (b), and the metal fitting body 1 can be attached by engaging with the end of the fastening piece B2 of the band B. The shape and effect of the through hole 11 are the same as those of the previous embodiment, so a description thereof will be omitted. [Explanation of symbols]

[0021] 1 Bracket body 10 Fixed piece 11 Through hole 12 Inner edge 13 Anti-rotation piece 20 Engagement piece 21 Engagement part 30 Locking piece A Hexagonal bolt A1 Head corner A2 Head side A3 Threaded part A4 Fastening nut B-Band B1 Turnbuckle B2 Fastening piece B3 Mounting piece B4 Connecting nut C Hanging bolt D Piping X Virtual circumscribing circle

Claims

1. A hexagonal bolt anti-rotation fitting for a piping band, which prevents a hexagonal bolt from rotating together with a tightening nut that secures the piping by tightening a band wrapped around the outer circumference of the piping, characterized in that the fitting body is composed of a fixing piece with a through hole that fits into the head side of the hexagonal bolt, and a locking piece that engages with the tightening piece of the band, the inner edge of the through hole is formed outside an imaginary circumscribing circle that follows the head corner of the hexagonal bolt, and the tip surface protrudes inward from the inner edge toward the head side of the hexagonal bolt, forming an anti-rotation piece that comes into planar contact with the head side of the hexagonal bolt.

2. 2. A piping band hexagonal bolt rotation prevention fitting according to claim 1, wherein the rotation prevention pieces are formed at two or more opposing positions on a side surface of the head of the hexagonal bolt.

3. 3. A piping band hexagonal bolt rotation prevention fitting as claimed in claim 1 or 2, characterized in that the locking piece is locked to one or both end edges of the fastening piece of the band, and the fitting body is formed into an approximately L-shape or an approximately U-shape.

4. 3. A hexagonal bolt rotation prevention fitting for a piping band as described in claim 1 or 2, characterized in that an engaging piece extending from one of the locking pieces and having an engaging portion that engages with the threaded portion of the hexagonal bolt is formed opposite the fixed piece.

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