JP7483588B2 - Pipe Connectors - Google Patents

Description

This invention relates to a pipe connector for connecting a spirally corrugated pipe.

A pipe connection structure for connecting a corrugated pipe to the wall of an underground box such as a handhole has been known (see, for example, Patent Document 1). As shown in Figure 19, this pipe connection structure 23 includes a receiving joint 24 inserted into a through hole 21a in the wall 21, a fastening member 25 and a bell mouth 26 for fixing the receiving joint 24 to the wall 21, a plug-in joint 27 screwed into the corrugated pipe 22 and then inserted into the receiving joint 24, and a retaining member 28 for retaining the plug-in joint 27.

JP 2008-014455 A

However, in the conventional pipe connection structure 23, when screwing the plug-in joint 27 (connection adapter) into the helical corrugated pipe 22, if the helical corrugated pipe 22 has a curl, it is necessary to correct the curl inside the plug-in joint 27 while screwing it forward, or the curl creates a lot of friction between the helical corrugated pipe 22 and the plug-in joint 27, making the installation of the plug-in joint 27 into the helical corrugated pipe 22 difficult.

This invention was made to solve the above-mentioned conventional shortcomings, and its purpose is to provide a pipe connector that allows a connection adapter to be easily attached to the end of a spirally corrugated pipe.

In order to achieve the above object, the pipe connector according to the present invention has the following configuration.
The pipe connector according to the invention of claim 1 is a pipe connector to which a helical corrugated pipe is connected, and includes a connection adapter formed in a cylindrical shape to receive an end of the helical corrugated pipe, and having a protrusion on its inner surface that fits into a helical recess on the outer surface of the helical corrugated pipe, and is attached to the end of the helical corrugated pipe by rotating it in a spiral shape from one end side, and a main body. The main body has a cylindrical connection part into which the end of the helical corrugated pipe to which the connection adapter is attached is inserted together with the connection adapter. The connection part is provided with a slip-out prevention part that prevents the helical corrugated pipe and the connection adapter from slipping out of the connection part. Here, the connection adapter has a plurality of vertically split divided bodies having a split section extending in the axial direction, and an assembly part that assembles the divided bodies to each other. The assembly part is provided only at a position biased toward the one end side, and the multiple divided bodies are capable of being separated from each other at the other end side opposite to the one end side.

According to this pipe connector, the pipe connector includes a connection adapter and a main body having a connection portion. The connection adapter is attached to the end of the helical corrugated pipe by inserting the inner protrusion of the connection adapter into the helical recess on the outer surface of the helical corrugated pipe and rotating the connection adapter so that the connection adapter fits around the outer periphery of the helical corrugated pipe from one end side. When the end of the helical corrugated pipe together with the connection adapter is inserted into the connection portion of the main body, the slip-out prevention portion provided on the connection portion prevents the helical corrugated pipe and the connection adapter from slipping out of the connection portion, and the helical corrugated pipe is connected to the connection portion and thus to the pipe connector. Here, the connection adapter has multiple vertically split divided bodies that are assembled to each other by an assembly portion located to one side of the one end, and the other ends can be separated from each other. Therefore, even if the helical corrugated tube has a tendency to curl when the connection adapter is attached to the end of the helical corrugated tube, causing a lot of friction between the helical corrugated tube and the connection adapter, the friction can be reduced by separating the multiple segments from each other, making it possible to reduce the resistance to attachment.

The pipe connector according to the invention described in claim 2 is the pipe connector described in claim 1, in which the plurality of divided bodies are provided with movement restriction parts that engage with each other and restrict relative movement in the axial direction. By providing the movement restriction parts in addition to the assembly part, the structure of the assembly part can be simplified.

The pipe connector according to the invention of claim 3 is the pipe connector according to claim 2, in which the movement restricting portion is provided on the portion of the divided surface where the protrusion is present. By providing the movement restricting portion on the divided surface, the movement restricting portion can be protected by the divided bodies, and by providing the movement restricting portion on the portion of the divided surface where the protrusion is present, the movement restricting portion can be easily formed.

The pipe connector according to the invention described in claim 4 is a pipe connector according to any one of claims 1 to 3, in which an inner-side water-swellable sheet is provided on the inner surface of the connection adapter at a position biased toward the other end so as to be sandwiched between the connection adapter and the spirally corrugated pipe. By providing the inner-side water-swellable sheet, water is stopped between the inner surface of the connection adapter and the outer surface of the spirally corrugated pipe. And, by providing this inner-side water-swellable sheet at a position biased toward the other end where the multiple segments can be separated from each other, when the connection adapter is attached to the end of the spirally corrugated pipe, the other ends of the multiple segments are separated from each other, reducing friction between the spirally corrugated pipe and the inner-side water-swellable sheet and reducing the resistance to attachment.

The pipe connector according to the invention described in claim 5 is a pipe connector according to any one of claims 1 to 4, in which an outer surface water-swellable sheet is provided on the outer surface of the connection adapter so as to be sandwiched between the connection adapter and the connection part. The outer surface water-swellable sheet is stretchable in the circumferential direction of the connection adapter and is provided across at least the adjacent divided bodies. The provision of the outer surface water-swellable sheet provides a watertight seal between the outer surface of the connection adapter and the inner surface of the connection part. Since the outer surface water-swellable sheet is provided across the adjacent divided bodies and is stretchable, it allows the other end of the divided bodies to open and prevents damage to the assembly part due to excessive opening.

The pipe connector according to claim 6 is a pipe connector according to any one of claims 1 to 5, in which a water-swellable sheet is provided between the divided surfaces on at least one of the opposing divided surfaces so as to be sandwiched between the adjacent divided bodies. By providing the water-swellable sheet between the divided surfaces, water is stopped between the divided surfaces of the adjacent divided bodies.

The pipe connector of this invention has multiple segments spaced apart from one another, which reduces the resistance to installation and makes it easy to attach the connection adapter to the end of the helical corrugated pipe.

FIG. 1 is a vertical cross-sectional view of an embodiment of the present invention. This is also a front view. FIG. FIG. 11 is a longitudinal cross-sectional view showing the state immediately before the helical wave tube with the connection adapter attached is inserted into the connection portion of the main body. FIG. FIG. 13 is a perspective view of the same connecting adapter in an inverted position. FIG. FIG. 8 is a cross-sectional view taken along line AA in FIG. 8 is a cross-sectional view taken along line BB in FIG. FIG. FIG. 13 is an exploded perspective view of the same with the connection adapter turned in the reverse direction. 13A and 13B are views showing the state when the connection adapter is attached to the helical corrugated pipe and the divided bodies are not separated from each other, where (a) is a longitudinal cross-sectional view and (b) is a front view. 13A and 13B are views showing the state when the divided bodies are separated from each other during the process of attaching the connection adapter to the helical corrugated tube, where FIG. FIG. 11 is a longitudinal cross-sectional view showing a connection adapter with a water-swellable sheet according to another embodiment of the present invention. This is also a front view. 17 is a cross-sectional view taken along line CC in FIG. FIG. 13 is a longitudinal cross-sectional view of a main portion showing a state in which a spirally corrugated pipe having a connection adapter with a water-swellable sheet attached thereto is inserted into a connection portion of a main body. FIG. 1 is a front view showing a conventional pipe connection structure with the upper half cut away.

The following describes the embodiment of the pipe connector according to the present invention with reference to the drawings.

Figures 1 to 14 show one embodiment of the present invention. In the figures, reference numeral 1 indicates a wall of an underground burial box or the like. Reference numeral 2 indicates a spirally corrugated pipe whose peripheral wall is formed by a spiral undulation. Reference numeral 3 indicates a pipe connector to which the spirally corrugated pipe 2 is connected.

The pipe connector 3 comprises a connection adapter 4 and a main body 5. The connection adapter 4 is formed in a cylindrical shape to receive the end of the helical corrugated pipe 2, and has a protrusion 4a on the inner surface that fits into the helical recess 2a on the outer surface of the helical corrugated pipe 2, and is attached to the end of the helical corrugated pipe 2 by rotating it in a spiral shape from the one end 4b side. This connection adapter 4 has multiple (two in the illustrated embodiment) divided bodies 4e, 4e in a vertical split shape having a split surface 4d extending in the axial direction 4c of the connection adapter 4, and an assembly part 4f that assembles the divided bodies 4e, 4e to each other. This assembly part 4f is provided only at a position biased toward the one end 4b side (i.e., a position shifted toward the one end 4b side from the center in the axial direction 4c of the connection adapter 4, preferably a position beside the one end 4b as shown in the illustrated embodiment), and the multiple divided bodies 4e, 4e are capable of being separated from each other at the other end 4g side opposite to the one end 4b side. The multiple divided bodies 4e, 4e are provided with movement restriction parts 4h that engage with each other to restrict relative movement in the axial direction 4c.

The main body 5 has a connection part 5a, into which the end of the helical wave pipe 2 to which the connection adapter 4 is attached is inserted together with the connection adapter 4. The connection part 5a is provided with a slip-out prevention part 5b that prevents the helical wave pipe 2 and the connection adapter 4 from slipping out of the connection part 5a.

Specifically, the corrugated pipe 2 is, for example, a protective pipe through which wires such as electric cables or pipes such as water pipes are passed.

The main body 5 includes a connector main body 6, a nut member 7, a connector 8 having the connection portion 5a, and a slip-out prevention body 9 having the slip-out prevention portion 5b. The main body 5 further includes first and second gaskets 10 and 11 as water-stopping members.

The connector body 6 is formed in a cylindrical shape and has an outwardly protruding flange 6a at its tip. A male thread 6b is formed on the outer surface of the connector body 6.

The connector 8 includes a first tubular portion 8a, a second tubular portion 8b spaced apart from the inside of the first tubular portion 8a, a connecting portion 8c connecting the first tubular portion 8a and the second tubular portion 8b at their rear ends, and the tubular connecting portion 5a. The connecting portion 5a extends rearward from the first tubular portion 8a, and the connecting portion 8c is provided at the bottom of the connecting portion 5a. A female thread 8d is formed on the inner surface of the first tubular portion 8a, and the female thread 8d is screwed into the male thread 6b of the connecting device main body 6, so that the connector 8 is attached to the connecting device main body 6 (more specifically, the rear end portion of the connecting device main body 6). The connecting portion 5a also has an accommodating recess 8e on its inner surface for accommodating the slip-out prevention body 9.

The slip-out prevention body 9 has a locking portion 9a as a slip-out prevention portion 5b, and the locking portion 9a locks the connection adapter 4 (more specifically, the locked portion 4i described below), so that the locking portion 9a (slip-out prevention portion 5b) prevents the spiral corrugated tube 2 and the connection adapter 4 from slipping out of the connection portion 5a. In detail, the slip-out prevention body 9 has a ring portion 9b formed in a ring shape and divided at one point in the circumferential direction, and the locking portion 9a. In detail, a plurality of locking portions 9a are provided so as to be aligned in the circumferential direction of the ring portion 9b. The locking portion 9a is formed to be curved so as to extend from the ring portion 9b and bend back, and a claw 9c that hooks onto the locked portion 4i is provided at the tip of the locking portion 9a.

The first packing 10 and the second packing 11 are formed in a ring shape and fitted around the outer periphery of the connector body 6. The first packing 10 is between the flange 6a of the connector body 6 and the wall 1, and the second packing 11 is between the nut member 7 and the wall 1. The connector body 6, and therefore the main body 5, are attached to the wall 1 by sandwiching the wall 1 between the flange 6a and the nut member 7 via the first and second packings 10, 11. Note that the reference symbol 1a in the figure indicates a through hole opened in the wall 1, and the connector body 6 is inserted into the through hole 1a.

As described above, the connection adapter 4 is formed in a cylindrical shape, and has a retaining portion 4i protruding from its outer surface. The protruding portion 4a of the connection adapter 4 is formed in a spiral shape and is a female thread that screws into the spiral of the outer surface of the spirally corrugated pipe 2. In addition, the connection adapter 4 is provided with an inner rib 4j at the end on the other end 4g side that protrudes inward (specifically, protrudes in a ring shape) and can abut against the tip of the spirally corrugated pipe 2. Therefore, this inner rib 4j restricts the entry of the spirally corrugated pipe 2 into the connection adapter 4. The tip of the spirally corrugated pipe 2 remains inside the connection adapter 4. The tip of this inner rib 4j is not flat but rounded.

The connection adapter 4 is composed of two divided bodies 4e, 4e, which are formed by splitting a tube vertically in half (i.e., equally divided) (see Figs. 11 and 12). The assembly part 4f is composed of an engaged part 4k provided on one divided body 4e and an engaging part 4m provided on the other divided body 4e, and the engaging part 4m engages with the engaged part 4k, so that the two divided bodies 4e, 4e are prevented from separating from each other at one end 4b of the connection adapter 4 where the assembly part 4f (i.e., the engaged part 4k and the engaging part 4m) are located, and the opposite end 4g side can separate from each other. In detail, the assembly part 4f is provided on the outside of the connection adapter 4, and the engaged part 4k and the engaging part 4m are formed protruding from the outer surface of the divided body 4e near the split surface 4d. More specifically, as shown in Figs. 6 and 10 to 12, the engaged part 4k has a protruding part 4n that protrudes in the circumferential direction so as to exceed the split surface 4d. The engaging portion 4m protrudes from a position set back from the divided surface 4d and extends in the circumferential direction beyond the divided surface 4d, and the inside of the engaging portion 4m set back from the divided surface 4d forms a recess 4p. The engaging portion 4m has a hook portion 4q facing inward at its extended tip. When assembling the divided bodies 4e, 4e to each other, the engaging portion 4m covers the engaged portion 4k, the recess 4p and the protrusion 4n are fitted together, and the hook portion 4q is hooked onto the end face of the engaged portion 4k opposite the protrusion 4n.

As the movement restricting portion 4h of the connection adapter 4, a first movement restricting portion 4r is provided on one side of the divided body 4e, and a second movement restricting portion 4s is provided on the other side of the divided body 4e. The movement restricting portion 4h, i.e., the first movement restricting portion 4r and the second movement restricting portion 4s, are provided on the part of the divided surface 4d where the protrusion 4a is present. In detail, the first movement restricting portion 4r is made of a hole, and the second movement restricting portion 4s is made of a protrusion that fits into the hole.

Next, the effects of the pipe connector 3 having the above configuration will be described. According to this pipe connector 3, the pipe connector 3 includes a connection adapter 4 and a main body 5 having a connection portion 5a. The connection adapter 4 is attached to the end of the helical corrugated pipe 2 by rotating the connection adapter 4 while inserting the inner protrusion 4a of the connection adapter 4 into the helical recess 2a on the outer surface of the helical corrugated pipe 2 so that the one end 4b of the connection adapter 4 is fitted to the outer periphery of the helical corrugated pipe 2. When the end of the helical corrugated pipe 2 is inserted into the connection portion 5a of the main body 5 together with the connection adapter 4, the slip-out prevention portion 5b provided on the connection portion 5a prevents the helical corrugated pipe 2 and the connection adapter 4 from slipping out of the connection portion 5a, and the helical corrugated pipe 2 is connected to the connection portion 5a and thus the pipe connector 3.

Here, the connection adapter 4 has a plurality of vertically split divisions 4e, 4e assembled to each other by an assembly part 4f located at a position biased toward the one end 4b, and the other end 4g side can be separated from each other. Therefore, even if the friction between the spirally corrugated tube 2 and the connection adapter 4 is large due to the spirally corrugated tube 2 having a curling tendency when the connection adapter 4 is attached to the end of the spirally corrugated tube 2, the friction can be reduced by separating the plurality of divisions 4e, 4e (more specifically, the other end 4g side of the plurality of divisions 4e, 4e) from each other, and the resistance to attachment can be reduced (see FIG. 14). In other words, according to this pipe connector 3, the plurality of divisions 4e, 4e (more specifically, the other end 4g side of the plurality of divisions 4e, 4e) are separated from each other, and the resistance to attachment can be reduced, and the connection adapter 4 can be easily attached to the end of the spirally corrugated tube 2.

In the illustrated embodiment, the main body 5 includes a connector main body 6 and a nut member 7. The main body 5 is attached to the wall 1 by sandwiching the wall 1 between the flange portion 6a of the connector main body 6 and the nut member 7 (see FIG. 4). That is, the main body 5 is attached to the wall 1 in advance, and then, as described above, the helical corrugated pipe 2 with the connection adapter 4 attached is connected to the connection portion 5a of the main body 5, so that the helical corrugated pipe 2 can be connected to the wall 1 to be connected (see FIG. 4 and FIG. 1).

In addition to the mounting portion 4f, the connection adapter 4 is provided with a movement restricting portion 4h that restricts the relative movement of the segments 4e, 4e in the axial direction 4c. This allows the function of the movement restricting portion 4h to be omitted from the mounting portion 4f, simplifying the structure of the mounting portion 4f. Furthermore, by providing the movement restricting portion 4h on the divided surface 4d, the movement restricting portion 4h can be protected by the segments 4e, and by providing the movement restricting portion 4h on the portion of the divided surface 4d where the protruding portion 4a is present, the movement restricting portion 4h can be easily formed.

The present invention is not limited to the above-described embodiment, and various other modifications are possible. For example, the slip-out prevention part 5b prevents the helical wave tube 2 and the connection adapter 4 from slipping out of the connection part 5a by engaging the connection adapter 4, but the slip-out prevention part 5b may also prevent the helical wave tube 2 and the connection adapter 4 from slipping out of the connection part 5a by engaging the helical wave tube 2 (more specifically, the helical part on the outer surface of the helical wave tube 2).

The connection adapter 4 may also be composed of three or more divided bodies 4e, 4e.

As shown in Figs. 15 to 18, the connection adapter 4 may be provided with an inner water-swellable sheet 12, an outer water-swellable sheet 13, or a water-swellable sheet 14 between the divided surfaces. Here, the water-swellable sheets 12, 13, and 14 are sheets that have the property of absorbing water and expanding, and are formed, for example, from nonwoven fabric.

The inner surface water-swellable sheet 12 is provided on the inner surface of the connection adapter 4 so as to be sandwiched between the connection adapter 4 and the spiral corrugated tube 2, and more specifically, is provided at a position on the inner surface of the connection adapter 4 that is biased toward the other end 4g (i.e., a position shifted toward the other end 4g from the center in the axial direction 4c of the connection adapter 4). The outer surface water-swellable sheet 13 is provided on the outer surface of the connection adapter 4 so as to be sandwiched between the connection adapter 4 and the connection part 5a. This outer surface water-swellable sheet 13 is extensible in the circumferential direction of the connection adapter 4 and is provided across at least adjacent divided bodies 4e, 4e. The divided surface water-swellable sheet 14 is provided on at least one surface (both surfaces in the illustrated embodiment) of the mutually opposing divided surfaces 4d, 4d so as to be sandwiched between adjacent divided bodies 4e, 4e.

In detail, the inner water-swellable sheet 12 is provided on each divided body 4e. More specifically, the inner water-swellable sheet 12 covers the divided body 4e over the entire inner circumference, and both end portions are bent to cover the divided surface 4d so as to also serve as the inter-divided surface water-swellable sheet 14, and both ends are folded back to the outer surface side of the divided body 4e. The outer water-swellable sheet 13 is provided over the entire outer circumference of the connection adapter 4. This outer water-swellable sheet 13 is provided on the other end 4g side of the outer surface of the connection adapter 4. Each water-swellable sheet 12, 13, 14 is then attached to the divided body 4e (connection adapter 4) by adhesive or heat welding.

However, the inner surface water-swellable sheet 12 does not have to double as the water-swellable sheet 14 between the divided surfaces, and the inner surface water-swellable sheet 12 and the water-swellable sheet 14 between the divided surfaces may be provided separately. The outer surface water-swellable sheet 13 does not necessarily have to be provided over the entire outer circumference of the connection adapter 4. The water-swellable sheet 14 between the divided surfaces does not have to be provided on both surfaces of the divided surfaces 4d, 4d that face each other, and may be provided on only one surface.

The provision of the inner water-swellable sheet 12 provides a watertight seal between the inner surface of the connection adapter 4 and the outer surface of the spirally corrugated pipe 2. The inner water-swellable sheet 12 is provided at a position biased toward the other end 4g side where the multiple segments 4e, 4e can be separated from each other, so that when the connection adapter 4 is attached to the end of the spirally corrugated pipe 2, the other ends 4g of the multiple segments 4e, 4e are separated from each other, reducing friction between the spirally corrugated pipe 2 and the inner water-swellable sheet 12 and reducing the resistance to attachment. In other words, in the conventional pipe body connection structure, if a nonwoven fabric for watertightness is provided on the inner surface of the plug joint, the plug joint is screwed forward while the spirally corrugated pipe compresses the nonwoven fabric so that the nonwoven fabric is firmly attached to the outer surface of the spirally corrugated pipe, which creates a very large friction and can make the attachment work very difficult. Therefore, by separating the other ends 4g of the multiple segments 4e, 4e from each other, the resistance to installation can be reduced, making installation work easier.

The inner water-swellable sheet 12 is provided on the inner surface of the connection adapter 4 closer to the other end 4g than the location where the assembly section 4f is provided. Therefore, the inner water-swellable sheet 12 is not present inside the location of the assembly section 4f, where there is almost no change in the size of the internal space in the connection adapter 4. This also reduces the resistance to attaching the connection adapter 4 to the helical corrugated pipe 2, making the installation work easier.

The provision of the outer water-swellable sheet 13 also provides a waterproof seal between the outer surface of the connection adapter 4 and the inner surface of the connection portion 5a. This outer water-swellable sheet 13 is provided across the adjacent segments 4e, 4e and is stretchable, allowing the other ends 4g of the segments 4e, 4e to open and preventing damage to the assembly portion 4f due to excessive opening.

In addition, the provision of a water-swellable sheet 14 between the divided surfaces provides watertightness between the divided surfaces 4d, 4d of adjacent divided bodies 4e, 4e.

2 Spiral wave pipe 2a Recess 3 Pipe connector 4 Connection adapter 4a Protrusion 4b One end 4c Axial direction 4d Partition surface 4e Divided body 4f Attachment portion 4g Other end 4h Movement restricting portion 5 Main body 5a Connection portion 5b Slip-out prevention portion 12 Inner surface water-swellable sheet 13 Outer surface water-swellable sheet 14 Water-swellable sheet between the parting surfaces

Claims (6)

A pipe connector for connecting a spirally corrugated pipe,
a connection adapter formed in a cylindrical shape to receive the end of the helical corrugated tube, having a protrusion on its inner surface that fits into a helical recess on the outer surface of the helical corrugated tube, and being attached to the end of the helical corrugated tube from one end side by rotating in a helical manner; and a main body;
the main body has a cylindrical connection portion into which the end portion of the spirally corrugated tube to which the connection adapter is attached is inserted together with the connection adapter;
the connection portion is provided with a slip-out prevention portion that prevents the spiral wave tube and the connection adapter from slipping out of the connection portion;
the connection adapter has a plurality of vertically split divisions having split sections extending in an axial direction thereof, and an assembly portion for assembling the divisions to each other;
The assembly portion is provided only at a position biased toward the one end, and the multiple divided bodies are capable of being separated from each other at the other end side opposite the one end side. The pipe connector according to claim 1, wherein the plurality of divided bodies are provided with movement restriction parts that engage with each other to restrict relative movement in the axial direction. The pipe connector according to claim 2, wherein the movement restriction portion is provided on the part of the divided surface where the protrusion is present. The pipe connector according to any one of claims 1 to 3, wherein an inner-side water-swellable sheet is provided on the inner surface of the connection adapter at a position offset toward the other end so as to be sandwiched between the connection adapter and the spirally corrugated pipe. an outer surface water-swellable sheet is provided on an outer surface of the connection adapter so as to be sandwiched between the connection adapter and the connection portion;
5. The pipe connector according to claim 1, wherein the outer water-swellable sheet is extensible in the circumferential direction of the connection adapter and is provided across at least the adjacent divided bodies. A pipe connector according to any one of claims 1 to 5, in which a water-swellable sheet is provided between the divided surfaces on at least one surface of the divided surfaces that face each other so as to be sandwiched between the adjacent divided bodies.

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