JP7645528B2 - Tube connection structure - Google Patents

Description

The present invention relates to a connection structure for pipes such as drainage pipes.

A conventional pipe connection structure is known in which pipes are connected watertightly to each other using a water-stopping member. In the pipe connection structure described in Patent Document 1, the end of one pipe is enlarged in diameter to form a receiving portion into which the other pipe can be inserted, and a male screw is formed on the outer periphery for screwing with a nut. The end of the other pipe is inserted into the receiving portion, and a groove is formed on the outer periphery over the entire circumference, and a water-stopping member is fitted into the groove. The water-stopping member is a packing made of an elastic member having a generally triangular cross section, and is pressed by the nut toward the first pipe when one pipe and the nut are screwed together.
The end of the first pipe is formed with a tapered surface that is inclined toward the inside, and the water-stopping member pressed against the first pipe by screwing the nut is pressured by the tapered surface so as to contract inward. At this time, the water-stopping member is pressed against the outer surface of the other pipe over its entire circumference, thereby connecting the pipes watertightly.

The structure described in Patent Document 2 is known as a pipe connection structure using another water-stopping member. The water-stopping member described in Patent Document 2 deforms so as to protrude inward when one pipe is connected to a nut, and the deformed portion presses against the side of the other pipe, thereby connecting the pipes watertightly.

JP 2009-058082 A JP 2015-124510 A

In the connection structure of the pipes by screwing as described in the above Patent Document 1, the nut must be tightened with an appropriate torque. That is, if the tightening force is less than the appropriate torque, the water-stopping member is not pressed watertightly, and there is a risk of water leakage, and if the tightening force is more than the appropriate torque, there is a risk of damage to the nut or other components. However, since the tightening torque varies depending on the worker, it is difficult to always tighten with the appropriate torque and ensure a certain construction quality. In addition, the connection structure described in Patent Document 1 requires the water-stopping member to be contracted inward while moving in the screwing direction by screwing, so a very high torque is required to connect the pipes watertightly, and it is difficult to improve the construction quality without causing differences depending on the worker.
In contrast, the water-stopping member in the pipe connection structure described in Patent Document 2 only deforms inward when fastened, and deforms significantly with little force, making it possible to reduce the torque required for fastening. However, the water-stopping member described in Patent Document 2 is difficult to position, and the water-stopping member may move from the appropriate position during construction or deform into an unexpected shape when connected, making it impossible to connect the pipes watertightly.

In view of the above problems, the present invention aims to provide a pipe connection structure that is easy to connect and has stable construction quality.

In order to solve the above problem, the present invention provides a first pipe having a receiving portion,
A second pipe inserted into the receiving portion;
a water-stopping member disposed watertightly between the first pipe and the second pipe;
A pipe connection structure including a connection member that is connected to the first pipe and connects the first pipe and the second pipe,
The water-stopping member is hollow with a space for deformation formed therein, and has a generally C - shaped cross section including a groove-shaped locking portion formed toward the first pipe or the connecting member to be locked to the first pipe or the connecting member,
The first pipe or the connection member includes a locked portion protruding toward the locking portion,
This is a pipe connection structure characterized in that the water-stopping member is pressed by the first pipe or the connecting member when the first pipe and the connecting member are connected, causing the hollow space to deform and be pressed against the outer surface of the second pipe.

In the present invention as set forth in claim 2, the engaged portion is
2. The pipe connection structure according to claim 1, wherein the connecting portion is formed wider than the locking portion.

In the present invention according to claim 3, the connecting member is annular,
The locking portion is
3. The pipe connection structure according to claim 1 , wherein the connecting member is formed over an entire circumference.

According to the present invention, when the first pipe and the connecting member are connected, the water-stopping member is pressed by the first pipe or the connecting member, and is deformed, and is pressed against the outer surface of the second pipe, so that the pipes can be connected with little torque. In addition, because the water-stopping member is engaged with the connecting member, it is possible to prevent the water-stopping member from shifting position or deforming into an unexpected shape when the second pipe is inserted or the connecting member is rotated.

FIG. 2 is an exploded view showing the tube body connection structure according to the first embodiment. FIG. 4 is a side view showing the first tube. 3A is a cross-sectional view showing a state in which a second tube is inserted into a first tube, and FIG. 3B is an enlarged view of part A in FIG. 3A. 4(a) is a cross-sectional view showing a state in which the first pipe body and the second pipe body are watertightly connected, and FIG. 4(b) is an enlarged view of part A in FIG. 4(a). FIG. 5A is a cross-sectional view showing a state in which a second tube is inserted into a first tube in a second embodiment, and FIG. 5B is an enlarged view of part A in FIG. 6(a) is a cross-sectional view showing a state in which the first pipe body and the second pipe body are watertightly connected, and FIG. 6(b) is an enlarged view of part A in FIG. 6(a). 7A is a cross-sectional view showing a state in which a second tube is inserted into a first tube in a third embodiment, and FIG. 7B is an enlarged view of part A in FIG. 8(a) is a cross-sectional view showing a state in which the first pipe body and the second pipe body are watertightly connected, and FIG. 8(b) is an enlarged view of part A in FIG. 8(a).

The pipe connection structure of the present invention will be described below with reference to the drawings. Note that the following description is provided to facilitate understanding of the embodiment, and is not intended to limit the invention.

As shown in Figures 1 to 4, the pipe connection structure in this embodiment is composed of a first pipe 1, a second pipe 2, a water-stopping member 3, and a connecting member 4.

The first pipe 1 is a cylindrical drainage pipe made of a hard resin material, and is provided at its end with a receiving portion 11. The receiving portion 11 is cylindrical and has an inner diameter that is approximately the same as the outer diameter of the second pipe 2. A step 12 is formed on the inner surface of the end of the receiving portion 11, in which the water-stopping member 3 is disposed, and a groove 13 is formed on the outer surface to engage with an engaging portion 42 of the connecting member 4, which will be described later.
As shown in Figure 2, with the engaging portion 42 positioned inside the groove portion 13, by rotating the connecting member 4 clockwise, a first groove portion 14 which is an inclined surface that brings the connecting member 4 closer to the first pipe body 1, and a second groove portion 15 which is formed in the circumferential direction of the first pipe body 1 from the end of the first groove portion 14 are engraved, and a loosening prevention member 16 is protruded outward from the second groove portion 15.

The second pipe 2 is a cylindrical drainage pipe, and during installation, the end is appropriately cut to adjust the length depending on the piping layout and then attached. Regardless of where the second pipe 2 is cut, the cross section and its neighboring parts will have the same outer diameter shape. The outer diameter of the second pipe 2 is approximately the same as the inner diameter of the receiving part 11, and the end is inserted into the receiving part 11.

The water-stopping member 3 is a packing made of an elastic material such as rubber or silicone, which is generally C-shaped in cross section and has an annular shape, and is disposed watertightly against the inner peripheral surface of the first pipe 1 and the outer peripheral surface of the second pipe 2. The water-stopping member 3 has an engagement portion 31 formed on the surface facing the first pipe 1, i.e., toward the connecting member 4. When no stress is applied to the water-stopping member 3 and it is not deformed, its inner diameter is generally the same as the inner diameter of the receiving portion 11 and the outer diameter of the second pipe 2.
The locking portion 31 is a groove-like recess formed around the entire circumference of the water-stopping member 3, and is locked to the connecting member 4 by inserting the locked portion 43 of the connecting member 4 therethrough.

The connecting member 4 is a nut member having an opening formed inside through which the second tubular body 2 is inserted, and has a flange portion 41 , an engaging portion 42 , and a locked portion 43 .
The flange portion 41 extends outward from the end portion of the connecting member 4 on the first tubular body 1 side, and an engagement portion 42 that protrudes inward is formed from the outer end portion of the flange portion 41, while an engagement portion 43 is formed from the inner end portion of the flange portion 41 toward the first tubular body 1.
The engaging portion 42 is formed to protrude inward in a large diameter portion extending from the outer end of the flange portion 41 toward the first pipe 1, and is disposed in a groove portion 13 formed in the first pipe 1 when installation is completed. The engaging portion 42 is slidable in the groove portion 13, and the connecting member 4 is moved in the axial direction of the first pipe 1 by rotating the connecting member 4.
The locked portion 43 is a cylindrical projection that projects toward the locking portion 31 of the water-stopping member 3 , and the width of the locked portion 43 is substantially the same as that of the locking portion 31 .

The first tube 1 and the second tube 2 are connected as follows:

First, the locking portion 31 of the water-stopping member 3 is locked to the locked portion 43, and the engaging portion 42 of the first pipe 1 is placed in the groove 13 to connect the first pipe 1 to the connecting member 4. At this time, since the locked portion 43 has substantially the same width as the locking portion 31, the water-stopping member 3 is not deformed and is only positioned relative to the connecting member 4. Furthermore, although the locked portion 43 is locked to the locking portion 31 of the water-stopping member 3, the locked portion 43 does not reach the end of the water-stopping member 3, and the water-stopping member 3 is in a hollow state.
3, the second pipe 2 is inserted into the receiving portion 11 of the first pipe 1. At this time, the second pipe 2 passes through the connecting member 4, and the water-stopping member 3 comes into contact with the outer periphery of the second pipe 2, but because the inner diameter of the water-stopping member 3 in an undeformed state is substantially the same as the outer diameter of the second pipe 2, no friction occurs that would prevent the water-stopping member 3 from being inserted into the receiving portion 11. In addition, because the locked portion 43 is locked to the locking portion 31, the water-stopping member 3 is not displaced during insertion.
Next, the connection member 4 is rotated clockwise until the engaging portion 42 abuts against the end of the second groove 15. At this time, the engaging portion 42 slides inside the first groove 14, causing the connection member 4 to move in the axial direction toward the first pipe 1. At this time, as shown in FIG. 4 , the water-stopping member 3 abuts against the step portion 12, and is pressed by the connection member 4 and the first pipe 1, causing the water-stopping member 3 to deform so as to be in pressure contact with the outer surface of the second pipe 2.
Then, due to friction caused by the pressing of the water-stopping member 3, the first pipe 1 and the second pipe 2 are connected watertightly, and the second pipe 2 cannot be removed from the first pipe 1. In addition, the engaging portion 42 overcomes the locking member 16 formed in the second groove portion 15, thereby preventing the connecting member 4 from rotating unexpectedly and causing the connection to be released.

When disconnecting the first pipe 1 and the second pipe 2, the connecting member 4 is rotated counterclockwise. At this time, the connecting member 4 moves axially away from the first pipe 1, and the water-stopping member 3 returns to its original shape due to its own elasticity. This reduces the friction between the water-stopping member 3 and the second pipe 2, making it possible to remove the second pipe 2 from the first pipe 1.

In the present invention, the connection between the first pipe 1 and the second pipe 2 is completed by rotating the connection member 4 until the engagement portion 42 abuts against the end of the second groove portion 15. Therefore, the worker can easily determine how far to rotate the connection member 4, and the work quality can be stabilized by eliminating variations in the tightening torque by the worker.
Furthermore, the water-stopping member 3 of the present invention does not move in the axial direction of the second pipe 2 when it is pressed against the second pipe 2. Therefore, it can be deformed with less force than conventional water-stopping members. Furthermore, the water-stopping member 3 is hollow with a space formed inside when it is engaged with the connecting member 4. Therefore, the water-stopping member 3 has a space inside for deformation, so it can be greatly deformed with little force. This is preferable for a connection structure using the groove portion 13 and the engagement portion 42, as in this embodiment, which achieves connection with fewer rotations or movements than screwing.
Furthermore, since the water-stopping member 3 is engaged with the connecting member 4, it is possible to prevent the water-stopping member 3 from shifting out of position or being deformed into an unexpected shape when the second tubular body 2 is inserted or the connecting member 4 is rotated.

In the first embodiment described above, the water-stopping member 3 was engaged with the connecting member 4, but it may be engaged with the first pipe body 1 as in the second embodiment shown in Figures 5 and 6.

Furthermore, when the water-stopping member 3 is engaged with the first tubular body 1 or the connecting member 4, the hollow space formed inside is crushed, thereby causing the water-stopping member 3 to deform. However, as in the third embodiment shown in Figures 7 and 8, the water-stopping member 3 may also be deformed by inserting the engaged portion 43 into the water-stopping member 3.
The locked portion 43 according to the third embodiment is wider than the locking portion 31 at the base end side, and a positioning protrusion 44 narrower than the locking portion 31 is formed at the end on the water-stopping member 3 side. Here, when the first pipe 1 and the second pipe 2 are not connected, that is, when the engagement portion 42 is disposed in the first groove portion 14, the water-stopping member 3 is locked to the positioning protrusion 44 of the locked portion 43 as shown in Fig. 7, and only the positional deviation is prevented. Here, when the second pipe 2 is inserted and the connection member 4 is rotated clockwise, the locked portion 43 wider than the locking portion 31 is inserted into the water-stopping member 3 as shown in Fig. 8, and the water-stopping member 3 is deformed to cover the locked portion 43 and is pressed against the outer surface of the second pipe 2. At this time, the first pipe 1 and the second pipe 2 are watertightly connected to each other due to friction caused by the pressing of the water-stopping member 3, and the second pipe 2 cannot be removed from the first pipe 1.

Although the embodiments of the present invention have been described above, the pipe connection structure of the present invention is not limited to the shapes of the respective embodiments, and various design changes may be made within the scope of the gist of the invention. For example, the locking portion is formed around the entire circumference of the annular water-stopping member, but may be formed only on a part of it. Similarly, the locked portion corresponding to the locking portion may be formed only on a part of the first pipe or the connecting member.
Furthermore, the pipe body may be a pipe body constituting a drain pipe, a water supply pipe, or an air intake pipe used in a washstand, a bathtub, or a sink, or may be other pipes.

REFERENCE SIGNS LIST 1 First pipe 11 Receiving portion 12 Step portion 13 Groove portion 14 First groove portion 15 Second groove portion 16 Locking member 2 Second pipe 3 Water-stopping member 31 Locking portion 4 Connecting member 41 Flange portion 42 Engagement portion 43 Locked portion 44 Positioning projection

Claims (3)

A first tubular body having a receiving portion;
A second pipe inserted into the receiving portion;
a water-stopping member disposed watertightly between the first pipe and the second pipe;
A pipe connection structure including a connection member that is connected to the first pipe and connects the first pipe and the second pipe,
The water-stopping member is hollow with a space for deformation formed therein, and has a generally C - shaped cross section including a groove-shaped locking portion formed toward the first pipe or the connecting member to be locked to the first pipe or the connecting member,
The first pipe or the connection member includes a locked portion protruding toward the locking portion,
A pipe connection structure characterized in that the water-stopping member is pressed by the first pipe or the connecting member when the first pipe and the connecting member are connected , causing the hollow space to deform and for the water-stopping member to be pressed against the outer surface of the second pipe. The engaged portion is
The pipe connection structure according to claim 1, characterized in that the width of the connecting portion is greater than that of the locking portion. The connecting member is annular,
The locking portion is
3. The pipe connection structure according to claim 1 , wherein the connecting member is formed over an entire circumference.

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