Clamp structure and clamp

Abstract

To provide a clamp structure which can fix a pipe easily without damaging components even in a limited work space in less time.SOLUTION: A clamp structure includes an electric fusion joint F and clamps 100 each of which holds a pipe P inserted into the electric fusion joint F. The clamp structure includes: holding parts 11 each of which contacts with the pipe P to hold the pipe P; attachment parts 12 each of which is provided at the holding part 11 and attaches the holding part 11 to the electric fusion joint F; and fastening tools 20 each of which engages with the holding part 11. The fastening tool 20 is fastened to the holding part 11 to reduce a diameter of the holding part 11 to hold the pipe P with the holding part 11.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a clamp structure.

Background Art

[0002] When joining pipes, an electric fusion joint is preferably used. When fusing pipes with an electric fusion joint, the pipes may be temporarily held by a clamp to prevent the pipes and the electric fusion joint from shifting. For example, a structure is disclosed in which a tapping screw is screwed into a clamp portion composed of two members to tighten and fix the pipe (Patent Document 1). Also, a clamp is disclosed in which a mounting portion is attached to an electric fusion joint with a pipe inserted therein, and the pipe is held by tightening the pipe with a tightening band portion connected to the mounting portion (Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Regarding the above-described fixing method using tapping screws, it takes time for construction because it is necessary to tighten the screws by an appropriate amount. Alternatively, although the screws can be tightened quickly using a power driver, there is a problem that if tightened too much, they will be damaged. In addition, when tightening the pipe with the tightening band, it is necessary to fit the engaging portion with a tool. At this time, it is necessary to apply a large force to the engaging portion with the tool. Further, there is only one operating portion for tightening with the tool in the circumferential direction of the pipe, and depending on the space at the construction site, it is difficult to apply the tool to the operating portion, resulting in a problem that the construction becomes difficult.

[0005] The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a clamp structure that can easily fix a pipe with a limited working space with a small working time without damaging parts.

Means for Solving the Problems

[0006] In order to solve the above problems, the present invention proposes the following means. The clamp structure according to the present invention is a clamp structure including an electric fusion joint and a clamp that holds a pipe inserted into the electric fusion joint, and includes a holding portion that contacts the pipe and holds the pipe, and a mounting portion provided on the holding portion for mounting the holding portion to the electric fusion joint, and a tightening tool that engages with the holding portion. By tightening the tightening tool on the holding portion, the diameter of the holding portion is reduced, and the pipe is held by the holding portion.

[0007] According to this invention, by tightening the tightening tool on the holding portion, the diameter of the holding portion is reduced, and the pipe is held by the holding portion. Thereby, the pipe can be held without using a separate fastening member such as a bolt. Therefore, the working time can be reduced. Further, by not using a bolt, it is possible to prevent damage to parts by the bolt. In addition, the operation of tightening the tightening tool can be performed from any direction in the circumferential direction of the pipe. Therefore, the pipe can be easily fixed even in a limited working space. Furthermore, since the tightening tool is tightened on the screw portion formed on the holding portion, the diameter of the screw portion can be increased as compared with the case of tightening a bolt of a separate member from the clamp. Therefore, a larger tightening force can be obtained with a relatively small force. Therefore, the pipe can be more easily and surely fixed by the holding portion.

[0008] Further, at least one notch portion provided in the axial direction of the holding portion may be provided in at least one location in the circumferential direction of the holding portion.

[0009] According to the present invention, at least one notch provided in the axial direction of the holding portion is provided in at least one location in the circumferential direction of the holding portion. Thereby, it is possible to increase the amount of deformation of the holding portion when the fastener is tightened. Therefore, the pipe can be held more easily and reliably by the holding portion.

[0010] Further, a male screw portion may be formed on the outer peripheral surface or the inner peripheral surface of the holding portion, and the pipe may be held by tightening the fastener onto the male screw portion.

[0011] According to the present invention, a male screw portion is formed on the outer peripheral surface or the inner peripheral surface of the holding portion, and the pipe is held by tightening the fastener onto the male screw portion. Thereby, the holding portion can be tightened from any direction. That is, it is possible to prevent a problem that the tool cannot be applied to the engaging portion due to the surrounding working space, as compared with the case where the engaging portion provided at one location in the circumferential direction is tightened with a tool.

[0012] Further, the male screw portion may be a multi-start screw.

[0013] According to the present invention, the screw portion is a multi-start screw. Therefore, the fastener can be tightened onto the holding portion with fewer rotations.

[0014] Further, the holding portion and the fastener may be tightened by a bayonet structure.

[0015] According to the present invention, the holding portion and the fastener are tightened by a bayonet structure. Therefore, the amount of rotation required for tightening the fastener can be made 1 rotation or less.

[0016] Further, the holding portion may be connected to the electric fusion joint by a joint connecting portion.

[0017] According to the present invention, the holding part is connected to the electric fusion joint by the joint connecting part. That is, the electric fusion joint and the holding part are integrally formed by the joint connecting part. Therefore, since it is not necessary to attach a separate clamp to the electric fusion joint, the working time can be further shortened.

Effects of the Invention

[0018] According to the present invention, it is possible to provide a clamp structure that can easily fix a pipe with a small amount of working time, without damaging parts, even in a limited working space.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Modes for Carrying Out the Invention

[0020] Hereinafter, with reference to the drawings, a clamp structure according to an embodiment of the present invention will be described. As shown in FIG. 1, a tube P inserted into a cylindrical electric fusion joint F is held by a clamp 100 according to the present embodiment. The electric fusion joint F has a heating wire on the inner peripheral surface side. Also, the tube P is preferably made of resin. Hereinafter, the clamp structure refers to a structure including the clamp 100, or particularly the holding portion 11 (described later) of the clamp 100, and the electric fusion joint F. In the state shown in FIG. 1, by energizing from the terminal T, an electric current is loaded on the heating wire. As a result, the temperature of the heating wire rises, and the inner peripheral surface of the electric fusion joint F and the outer peripheral surface of the tube P inserted into the electric fusion joint F melt. Thereby, the electric fusion joint F and the tube P are fused. Hereinafter, when indicating the directions of the respective components, with reference to the electric fusion joint F and the tube P shown in FIG. 2, they may be referred to as the axial direction, the radial direction, and the circumferential direction.

[0021] The clamp 100 according to the present embodiment is used for temporarily holding in order to prevent the positions of the electric fusion joint F and the tube P from shifting in the above-described fusion process.

[0022] The clamp 100 is attached and used at an end portion in the axial direction of the electric fusion joint F when connecting the tube P by the electric fusion joint F shown in FIG. 2. The clamp 100 includes a main body 10 and a tightening tool 20. The main body 10 is a portion that directly grips the tube P inserted into the electric fusion joint F. As shown in FIG. 3, the main body 10 includes a holding portion 11, a mounting portion 12, a root portion 13, and a connecting portion 14.

[0023] The holding portion 11 is a portion that contacts the tube P and holds the tube P. Thereby, it is possible to prevent the tube P during the fusion process from shifting due to the electric fusion joint F. The holding portion 11 is a cylindrical member whose central axis is parallel to the axial direction of the electric fusion joint F so as to be positioned around the tube P inserted into the electric fusion joint F. A connecting portion 14 is provided at one end of the cylindrical shape in the holding portion 11 and is connected to the root portion 13. The holding portion 11 includes an external thread portion 11b on the outer peripheral surface of the cylindrical shape. Further, the holding portion 11 includes a protruding portion 11p on the inner peripheral surface of the cylindrical shape.

[0024] The external thread portion 11b is formed to engage with the fastener 20. The nominal diameter and pitch of the external thread portion 11b are provided to correspond to the internal thread portion 20n (described later) of the fastener 20 in consideration of the diameter of the holding portion 11 determined according to the outer diameter of the pipe P. Note that it is preferable that the outer diameter of the external thread portion 11b does not exceed the outer diameter of the connecting portion 14 (described later).

[0025] If the end of the external thread portion 11b is provided up to the axial end of the holding portion 11, there is a risk that the fastener 20 will be fitted in an inclined state and the internal thread portion 20n that does not correspond to the external thread portion 11b will be fitted (as a result of fitting in an inclined state, for example, the first external thread portion 11b and the second internal thread portion 20n will be fitted). Therefore, it is preferable that the end of the external thread portion 11b on the side opposite to the connecting portion 14 is provided so as not to reach the axial end of the holding portion 11, and it is preferable to have a cylindrical portion of about 2 to 5 mm from the axial end of the holding portion 11. This cylindrical portion has the effect of preventing the fastener 20 from fitting with the external thread portion 11b while being inclined by contacting the inner surface of the fastener 20 when the fastener 20 tries to engage with the external thread portion 11b in an inclined state.

[0026] The diameter of the external thread portion 11b is preferably a so-called tapered shape that decreases in diameter from one end to the other end of the cylindrical shape of the holding portion 11. Thereby, by tightening the fastener 20 to the holding portion 11, the holding portion 11 contracts in diameter and the protruding portion 11p contacts the pipe P, so that the pipe P can be gripped (details will be described later). Although a general single-thread is preferably used for the external thread portion 11b, a multi-thread as shown in FIG. 4 may be used.

[0027] The protrusion 11p is a protrusion provided in an annular shape along the cylindrical shape of the holding portion 11 on the inner peripheral surface of the holding portion 11. That is, when the holding portion 11 approaches the pipe P, only the protrusion 11p contacts the pipe P. Thereby, compared with the case where the entire holding portion 11 contacts the pipe P, the contact area with respect to the pipe P can be reduced. Therefore, it has the role of improving the contact pressure due to the tightening of the holding portion 11 and improving the holding force of the pipe P.

[0028] As described above, the holding of the pipe P by the holding portion 11 is achieved by the contact pressure between the pipe P and the protrusion 11p that occurs when the holding portion 11 is deformed and the protrusion 11p contacts the pipe P. Specifically, when the fixture 20 is tightened into the tapered male screw portion provided in the holding portion 11, the length in the circumferential direction of the holding portion 11 (the length of the circumference of the cylindrical shape) contracts. In other words, the holding portion 11 contracts in the radial direction.

[0029] As a result, the protrusion 11p approaches the pipe P and finally contacts it. That is, the holding portion 11 has a deformation allowance. The deformation allowance is preferably, for example, one that utilizes the properties of the material forming the main body 10. For this reason, it is preferable that the same resin as that of the pipe P and the electric fusion joint F is used for the main body 10.

[0030] Further, as the following shape, the holding force of the pipe P by the holding portion 11 may be improved by making the holding portion 11 more deformable. That is, for example, as shown in FIG. 5, a notch portion 11c may be provided in the cylindrical shape of the holding portion 11. The notch portion 11c is provided with the axial direction of the cylindrical shape of the holding portion 11 as the longitudinal direction, and has a shape in which a part of the axial direction is notched from the inner diameter side to the outer diameter side of the cylindrical shape of the holding portion 11. Alternatively, as shown in FIG. 6, the holding portion 11 may have an opening portion 11s in the cylindrical shape. The opening portion 11s is provided with the axial direction of the cylindrical shape of the holding portion 11 as the longitudinal direction, and has a shape in which the entire axial direction is notched from the inner diameter side to the outer diameter side of the cylindrical shape of the holding portion 11.

[0031] The notch portions 11c are provided at at least one location or a plurality of locations at intervals in the circumferential direction of the holding portion 11. Further, the opening 11s is provided at one location at an arbitrary portion in the circumferential direction of the holding portion 11. Further, the holding portion 11 may have one notch portion 11c, and one or a plurality of openings 11s may be provided at other portions.

[0032] When the main body 10 is provided with the opening 11s, even after the electric fusion joint F and the pipe P are fused, the main body 10 can be removed from the pipe P by deforming the holding portion 11 from the opening 11s after the fixture 20 is removed. Therefore, when it is necessary to remove the main body 10 from the electric fusion joint F after fusion, the main body 10 provided with the opening 11s is preferably used. When it is not necessary to remove the main body 10 from the electric fusion joint F, a main body 10 having only the notch portion 11c or having neither the notch portion 11c nor the opening 11s may be used. In this case, the completion of the work may be confirmed by the fact that the main body 10 cannot be removed from the electric fusion joint F.

[0033] The mounting portion 12 is used to mount the clamp 100 to the terminal T of the electric fusion joint F. A hole 12h adapted to the diameter of the terminal T is formed in the mounting portion 12, and it is mounted by hanging it on the terminal T. The mounting portion 12 is integrally formed with the base portion 13. The base portion 13 is a portion that connects the holding portion 11 and the mounting portion 12 in the main body 10. The base portion 13 is a planar member and is provided parallel to a plane orthogonal to the axial direction. When the central axis of the cylindrical holding portion 11 is used as a reference, the mounting portion 12 is connected to the outer end portion in the radial direction of the base portion 13. Further, the holding portion 11 is connected to the inner end portion in the radial direction. The connection between the holding portion 11 and the base portion 13 is made by a connecting portion 14 provided therebetween.

[0034] The connecting portion 14 connects the base portion 13 and the holding portion 11. The connecting portion 14 is formed by a part of the axial end portion of the cylindrical holding portion 11 protruding parallel to the axial direction. Note that the main body 10 composed of the above-described respective members is preferably integrally formed by, for example, injection molding or the like.

[0035] The above-described clamp structure is premised on the fact that the electric fusion joint F and the holding portion 11 are separate bodies, but is not limited thereto. For example, the holding portion 11 may be connected to the end portion of the electric fusion joint F. That is, as shown in FIGS. 7 and 8, the connection holding portion 11a may be formed in a shape connected by a joint connection portion 14a provided at the end portion of the electric fusion joint F. As shown in FIG. 9, a plurality of connection holding portions 11a each having a shape of a part of a cylindrical shape may be provided at intervals. In this case, the interval between the connection holding portions serves as the notch portion 11c or the opening portion 11s. Alternatively, one connection holding portion 11a having a notch portion 11c or an opening portion 11s in a part of a cylindrical shape may be connected to the end portion of the electric fusion joint F by the connection holding portion 11a.

[0036] The fastener 20 has a role of reducing the diameter of the holding portion 11 by engaging with the holding portion 11 of the main body portion and gripping the pipe P by the holding portion 11. The fastener 20 has a role of a so-called nut having a female screw portion 20n corresponding to the male screw portion 11b of the holding portion 11. The female screw portion 20n is preferably tapered corresponding to the above-described male screw portion 11b.

[0037] As shown in FIG. 1, the outer peripheral surface of the fastener 20 is cylindrical. Accordingly, when the fastener 20 is screwed into the holding portion 11, it is performed by rotating the fastener 20 by hand. Alternatively, the outer peripheral surface of the fastener 20 may be hexagonal columnar so that the fastener 20 can be screwed in by a tool such as a spanner.

[0038] In addition, although the male screw portion 11b and the female screw portion 20n are provided in the main body 10 and the fastener 20, respectively, any structure may be used as long as the fastener 20 is engaged with the main body 10 by tightening. For example, a bayonet structure instead of a screw structure may be used.

[0039] The clamping of the pipe P inserted into the electric fusion joint F by the clamp 100 having the above configuration is performed as follows. That is, first, the main body 10 and the clamp 20 are inserted into the pipe P to be inserted into the electric fusion joint F in advance. In that state, the pipe P is inserted into the electric fusion joint F. Then, the mounting portion 12 of the main body portion is hung on the terminal T of the electric fusion joint F. When using the electric fusion joint F having the connection holding portion 11a, only the clamp 20 is inserted into the pipe P, and then the pipe P is inserted into the electric fusion joint F.

[0040] Then, as shown in FIG. 10, the main body 10 of the clamp 100 is attached to the electric fusion joint F, and further, the pipe P is inserted into the main body 10 and the electric fusion joint F. Next, the clamp 20 is tightened onto the main body 10. Here, since the male screw portion 11b and the female screw portion 20n are tapered as described above, when the male screw portion 11b and the female screw portion 20n engage, the holding portion 11 provided with the male screw portion 11b contracts in diameter. Therefore, the inner peripheral surface of the holding portion 11 approaches the pipe P, and finally, the protrusion 11p of the holding portion 11 comes into contact with the pipe P. By further tightening the clamp 20 from there, the protrusion 11p and the pipe P are strongly contacted, or the protrusion 11p bites into the surface of the pipe P, thereby holding the pipe P.

[0041] As described above, according to the clamp structure according to the present embodiment, by tightening the clamp 20 into the holding portion 11, the holding portion 11 is contracted in diameter and the pipe P is held by the holding portion 11. Thereby, the pipe P can be held without using a fastening member such as a bolt separately. Therefore, the working time can be reduced. Further, by not using a bolt, it is possible to prevent the parts from being damaged by the bolt. In addition, the operation of tightening the clamp 20 can be performed from any direction in the circumferential direction of the pipe P. Therefore, the pipe P can be easily fixed even in a limited working space. Further, since the clamp 20 is tightened into the screw portion formed in the holding portion 11, the diameter of the screw portion can be increased as compared with the case of tightening a bolt of a separate member with the clamp 100. Therefore, a larger tightening force can be obtained with a relatively small force. Therefore, the pipe P can be more easily and reliably fixed by the holding portion 11.

[0042] Further, the holding portion 11 is provided with at least one notch in the circumferential direction of the holding portion 11 provided in the axial direction. Thereby, the amount of deformation of the holding portion 11 when the tightening tool 20 is tightened can be increased. Therefore, the pipe P can be held more easily and reliably by the holding portion 11.

[0043] In addition, a male screw portion 11b is formed on the outer peripheral surface or the inner peripheral surface of the holding portion 11, and the pipe P is held by tightening the tightening tool 20 into the male screw portion 11b. Thereby, the holding portion 11 can be tightened from any direction. That is, it is possible to prevent a problem that the tool cannot be applied to the engaging portion due to the surrounding working space, as compared with the case where the engaging portion provided at one place in the circumferential direction is tightened with a tool.

[0044] Further, the screw portion is a multi-start screw. Therefore, the tightening tool 20 can be tightened into the holding portion 11 with a smaller number of rotations.

[0045] In addition, the holding portion 11 and the tightening tool 20 are tightened by a bayonet structure. Therefore, the amount of rotation required for tightening the tightening tool 20 can be made one rotation or less.

[0046] In addition, the holding portion 11 (connecting and holding portion 11a) is connected to the electric fusion joint F by the joint connecting portion 14a. That is, the electric fusion joint F and the connecting and holding portion 11a are integrally formed by the joint connecting portion 14a. Therefore, since it is not necessary to attach a separate clamp 100 to the electric fusion joint F, the working time can be further shortened.

[0047] Note that the technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, on the inner peripheral surface of the holding portion 11, a plurality of protrusion portions 11p may or may not be provided. Alternatively, a plurality of holding portions 11 may be provided at intervals on the inner peripheral surface.

[0048] Also, in this embodiment, it has been described that the male screw portion 11b of the main body 10 and the female screw portion 20n of the fixture 20 are tapered, but it is not limited thereto. For example, either the male screw portion 11b or the female screw portion 20n may not be tapered. Alternatively, if the deformation allowance of the holding portion 11 can be ensured by the notch portion 11c or the opening portion 11s, both the male screw portion 11b and the female screw portion 20n may not be tapered. Also, when shipping the clamp 100, the main body 10 and the fixture 20 may be shipped integrally in a state where they are engaged so that the holding portion 11 does not reduce in diameter. Also, although it has been described that the male screw portion 11b is provided on the outer peripheral surface of the holding portion 11, it is not limited thereto. For example, if the fixture 20 is configured such that a U-shaped cross-sectional shape is formed in a ring shape and a male screw is provided on the inner surface on the inner diameter side of the annular shape in the U-shaped cross-section, a female screw may be formed on the inner peripheral surface of the holding portion 11.

[0049] In addition, within the scope not departing from the gist of the present invention, it is possible to appropriately replace the constituent elements in the above-described embodiment with well-known constituent elements, and the above-described modification examples may also be appropriately combined.

Explanation of Reference Numerals

[0050] 10 Main body 11 Holding portion 11a Connecting and holding portion 11b Male screw portion 11c Notch portion 12 Mounting portion 14 Connecting portion 14a Joint connecting portion 20 Fixture 20n Female screw portion 100 Clamp F Electric fusion joint P Pipe

Claims

1. an electric fusion joint having a terminal; a clamp for holding a tube inserted into the electric fusion joint; a holding portion that is in contact with the pipe and holds the pipe, the holding portion being separate from the electric fusion joint; an attachment portion provided on the holding portion and having a hole through which the holding portion can be attached to the terminal of the electric fusion joint; A fastener that engages with the holding portion; Equipped with The holding portion has a protrusion formed in a circumferential direction on an inner circumferential surface of the holding portion, The clamping tool is fastened to the holding portion to reduce the diameter of the holding portion and hold the tube with the holding portion. Clamp structure.

2. The holding portion has at least one notch provided in the axial direction of the holding portion in the circumferential direction of the holding portion. The clamp structure according to claim 1 .

3. The position of the protrusion in the axial direction of the holding portion overlaps with the position where the notch is provided. The clamp structure according to claim 2 .

4. The outer peripheral surface of the fastener is hexagonal prism-shaped. The clamp structure according to any one of claims 1 to 3.

5. The holding portion is connected to the electric fusion joint by a joint connecting portion. A clamp structure according to any one of claims 1 to 4.

6. An electric fusion joint having a terminal, and a clamp for holding a tube inserted into the electric fusion joint; A clamp for use in a clamp structure comprising: The clamp structure includes: a holding portion that contacts the pipe and holds the pipe; an attachment portion provided on the holding portion and configured to attach the holding portion to the electric fusion joint; A fastener that engages with the holding portion; Equipped with The holding portion has a protrusion formed in a circumferential direction on an inner circumferential surface of the holding portion, The fastener is fastened to the holding portion to reduce the diameter of the holding portion. Holding the tube; The holding portion is separate from the electric fusion joint, The mounting portion has a hole formed therein to be attached to the terminal, The mounting portion and the holding portion are connected by a connecting portion. Clamp.

7. The holding portion has an opening cut out along the axial direction of the holding portion. The clamp of claim 6.

Images