JP2002257277A - Flexible bend pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily provide a desired curvature on a flush plane. SOLUTION: In this flexible bend pipe 10, connection faces A1 and A2 are tilted to the pipe axis in a straight pipe condition, and their tilting directions are alternately differentiated from each other. At construction, one side of short pipes of the flexible bend pipe 10 is turned by a predetermined angle to that on the other side, and the short pipes are turned by the same predetermined angle, while sequentially changing the turning direction alternately. Consequently, respective connection parts 18 are bent in the same bending direction at the same angle. In this way, the flexible bend pipe 10, bent at the predetermined angle on the flush plane, that is, the flexible bend pipe 10 with a predetermined curvature can be formed easily. By changing the turning angle properly, desired curvature can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a universally bent tube, and more particularly to a universally bent tube which connects two tubes with a predetermined curvature.

[0002]

2. Description of the Related Art Conventionally, a flexible tube 1 as shown in FIG. 8 has been known. The flexible tube 1 includes a plurality of short tubes 2
Which are connected to each other by a universal joint structure having a spherical shell 4 into which a spherical adapter 3 is rotatably fitted. In the flexible tube 1, the bending angle is restricted by locking the tube wall of the other short tube 2 to the tapered opening end 4a of the spherical shell 4. That is, according to the flexible curved tube 1, it is possible to obtain a curvature in a range from a straight state to a maximum bending angle (maximum curvature) when the flexible tube 1 is locked to the tapered opening end 4a.

[0003] Further, an example of a conventional flexible tube of this type is as follows.
Japanese Utility Model Application Laid-Open No. 6-November 15, 1994
80989 [F16L27 / 02, 11/18]
Is disclosed. This universal curved pipe (universal pipe joint) 5
As shown in FIG. 9, a tapered adjusting part 6 having both opening end faces formed so as to be inclined, the tapered adjusting part 6 and a straight adjusting part 7 having both opening end faces formed in parallel, etc. Are connected to each other by fitting the fitting projections 9 on the other opening end face into the fitting grooves 8 on the opening end face. According to the universal pipe joint 5, the taper-shaped adjusting component 6, the straight-shaped adjusting component 7, and the like are combined in an appropriate number in an appropriate direction, so that they are displaced in an arbitrary direction in parallel by an arbitrary size, and , It is possible to connect, for example, pipes (not shown) whose axes are displaced and are at bent positions.
In other words, connection can be made in accordance with the situation of individual differences at the construction site.

[0004]

However, the universally bent tube 1
In FIG. 8, it is possible to obtain a curvature in a range from a linear state to a maximum curvature. However, since the connection structure uses a spherical surface capable of obtaining an arbitrary bending direction, each connection portion has the same angle in the same direction. However, it was difficult to bend only the curvature, and the curvature could be restricted (fixed) only at the maximum curvature due to the engagement at the tapered opening end 4a. Therefore, when a predetermined curvature is required, it can be practically used only with the maximum curvature that can be fixed, and when a curvature smaller than the maximum curvature is required, it is necessary to separately perform work to fix the curvature at the maximum curvature. It was.

Further, universal fittings 5 (actual Hei 6-8098
In Japanese Patent Application Laid-open No. 9), connection can be made in accordance with individual situations. when a predetermined curvature in the plane, it has been rather a problem that troublesome.

SUMMARY OF THE INVENTION It is, therefore, a primary object of the present invention to provide a freely curved tube which can have a desired curvature in the same plane and can be simplified.

[0007]

According to the present invention, three or more short pipes having a joining surface inclined with respect to a pipe axis in a straight pipe state are connected to each other continuously and freely rotatable within the joining surface. It is a freely bendable pipe in which the directions of inclination of the joining surfaces are alternately changed in a straight pipe state.

[0008]

For example, a freely bendable pipe is constituted by three (first, second and third) short pipes, and a third short pipe is connected between the first and second short pipes. At the time of construction, when the third short pipe is rotated by a predetermined angle in the joint plane with respect to the first short pipe, the joint plane is inclined with respect to the pipe axis. Bend at a bending angle (curvature) according to. Subsequently, in the straight pipe state, the inclination directions of the joining surfaces are alternately different, so that the second short pipe is moved in the joining plane by the same angle in the direction opposite to the previous rotation direction with respect to the third short pipe. Rotate. Then, the third short pipe and the second short pipe are
It bends at the same bending angle in the direction along the bending direction of the first and third short tubes. In this way, the short pipe on the other side of the short pipe on one side of the freely bent tube, whereas by rotating from the side by the same predetermined angle while changing alternately the direction of rotation in order to the other side, in the same plane Thus, it is possible to simplify the tube into a freely curved tube having a predetermined angle, that is, a predetermined curvature. A desired curvature can be obtained by appropriately changing the rotation angle.

When a mark for providing a predetermined curvature is provided on the outer surface of the short pipe, each short pipe can be rotated by the same angle by aligning the mark.

[0010]

According to the present invention, a desired curvature can be obtained in the same plane, and it is only necessary to rotate each short tube by the same angle while alternately changing the rotation direction. Therefore, one universally curved tube can handle a plurality of required curvatures.

When a mark for providing a predetermined curvature is provided on the outer surface of the short tube, the desired curvature can be obtained more easily.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG.
Is for connecting two pipes with a predetermined curvature, and a first short pipe 1 to which a first pipe (not shown) is connected.
2, including a second short pipe 14 to which a second pipe (not shown) is connected, and at least one third short pipe 16 continuously connected between the first short pipe 12 and the second short pipe 14. .

In this embodiment, the third short pipe 16 is 2
In the following, the one connected to the first short pipe 12 may be referred to as a third short pipe 16a, and the one connected to the second short pipe 14 may be referred to as a third short pipe 16b.

Each short pipe, that is, the first short pipe 12 and the second short pipe 1
The fourth short tube 16 and the third short tube 16 are made of, for example, a synthetic resin such as vinyl chloride or the like, and have basically the same structure.
8 and are inclined with respect to the pipe axis.
And through A2, they are mutually rotatable in the joining plane.

That is, as shown in FIG. 2, the connecting portion 18 is provided with a first engaging portion 2 formed at the other end of one short tube.
0, formed at one end of the other short tube and the first
It includes a second engaging portion 22 engaged with the engaging portion 20.

The first engaging portion 20 has a surface B perpendicular to the pipe axis a.
Has a joint surface A1 inclined at a predetermined angle θ, while the second engagement portion 22 is inclined at a predetermined angle θ with respect to a surface B orthogonal to the pipe axis b, and It has a joining surface A2 that comes into contact. In addition, in FIG.
And when the pipe axis b is coaxial, that is, when the short pipes are in a straight pipe state.

A rubber ring receiving groove 24 is formed on the outer surface of the first engaging portion 20 over the entire circumference.
Is mounted with a rubber ring 26. Due to the compression force of the rubber ring 26, the first engagement portion 20 and the second engagement portion 22
Water stoppage is ensured and resistance to rotation is appropriately obtained. In addition, the inner surfaces near the joining surfaces A1 and A2 are chamfered in a tapered shape, so that a large step does not occur on the inner surface of the freely curved tube 10 even when bent.

In forming the connecting portion 18, for example,
First, the rubber ring 26 is mounted on the rubber ring accommodating groove 24, and a lubricant is applied to the rubber ring 26. Then, the first engagement portions 20 are pushed into the second engagement portions 22 by aligning the tube axes a and b coaxially. Then, the first engagement portion 20 is pushed into the second engagement portion 22 while the diameter of the second engagement portion 22 is expanded by the first engagement portion 20. And it pushes in until the joining surface A1 and the joining surface A2 contact, and the 1st engagement part 20 and the 2nd engagement part 22 are engaged (fit).

According to such a connecting portion 18, the joining surface A
In the plane of the first and A2, the first engaging portion 20 and the second engagement portion 2
2 can be relatively rotated. Since the joint surfaces A1 and A2 are inclined with respect to the pipe axes a and b, the angles formed by the pipe axes a and b change in the range of 0 to 2θ degrees by rotating them together. . That is, one short pipe (first engagement portion 20) and the other short pipe (second
0 ° (straight pipe state) up to 2θ
An arbitrary bending angle (curvature) can be obtained within a range of degrees (a state rotated from a straight pipe state by 180 degrees). Further, since the engagement (fitting) structure of the first engagement portion 20 and the second engagement portion 22 via the rubber ring 26 is provided, when the short tubes are relatively rotated by a predetermined angle, the positions thereof are changed. Fixedly maintained. That is,
The connecting part 18 can be fixed in a rotated state.

More specifically, as shown in FIG. 1, at the other end of the first short pipe 12 and the third short pipe 16b, first engagement portions 20 are formed in the same inclined state, respectively. At one end of the third short tube 16a and the second short tube 14 as the other party, the second engagement portions 22 are formed in the same inclined state. The other end of the third short pipe 16a is provided with the first short pipe 1
The first engagement portion 20 of the second and third short tubes 16b is rotated 180 degrees around the tube axis, that is, the inclination direction of the joining surface A1 is the first engagement of the first short tube 12 and the third short tube 16b. The first engaging portion 20 is formed in a state where the first engaging portion 20 is opposite to the joining portion 20. On the other hand, one end of the third short tube 16b which is the other end is provided with the second engaging portion 2 of the third short tube 16a and the second short tube 14.
2 is rotated 180 degrees around the pipe axis, that is, the inclination direction of the joining surface A2 is the third short pipe 16a and the second short pipe 1
4 in a state where the second engaging portion 22 is reversed.
2 are formed. Also, at one end of the first short pipe 12,
A rubber ring socket 28 for receiving a first tube (not shown) is formed, and the other end of the second short tube 14 is a spout connected to a second tube (not shown). In this embodiment, each short tube is integrally formed by injection of a synthetic resin.

Then, each of the first engaging portions 20 and the second engaging portions 22 are connected. In this way, as can be clearly understood from FIG. 1, in the straight pipe state in which the pipe axes of the short pipes are coaxial, the inclination angles of the joint surfaces A1 and A2 at the connection portions 18 are the same, as can be seen from FIG. They are connected to each other such that their inclination directions are alternately different (in opposite directions).

When the flexible tube 10 is constructed, for example, the universal tube 10 is first made to have a desired curvature, and then the first tube and the second tube (not shown) are respectively connected to the first short tube 1.
2 and the second short pipe 14. In order to make the universally curved tube 10 have a predetermined curvature, each short tube in a straight pipe state is relatively rotated by a predetermined angle (an angle at which a predetermined curvature is obtained). Specifically, for example, first, with respect to the first short pipe 12,
The short tube 16a is rotated in a predetermined direction by a predetermined angle. Then
The first short pipe 12 and the third short pipe 16a are bent at a bending angle according to the inclination angle θ and the rotation angle of the joining surfaces A1 and A2. Next, the third short pipe 16a, the third short pipe 16
b is rotated by the same predetermined angle in the direction opposite to the rotation direction of the third short tube 16a. Then, the third short pipe 16a and the third short pipe 16b are bent at the same bending angle in the direction along the bending direction of the first short pipe 12 and the third short pipe 16a. Then, with respect to the third short pipe 16b, the second short pipe 14 is moved in the same direction as the rotation direction of the third short pipe 16a, that is, in the direction opposite to the rotation direction of the third short pipe 16b. Rotate the same predetermined angle. Then, the third short pipe 16b and the second short pipe 14 are bent at the same bending angle in the direction along the previous bending direction. In this way, the short pipe on the other side of the short pipe on one side of the freely curved pipe 10, whereas by rotating from the side by the same predetermined angle while changing alternately the direction of rotation in order to the other side, each connection The flexible tube 1 bent at a predetermined angle in the same plane at the portion 18, that is, the flexible curved tube 1 having a predetermined curvature
It can be simplified to zero. Then, a freely curved tube having a desired curvature can be obtained by appropriately changing the rotation angle.

For example, when each short tube is relatively rotated by 180 degrees in each joint surface, the short tubes bend at a predetermined maximum bending angle 2θ as shown in FIG. Curvature. As can be seen from FIG. 3, when the curvature is set to the predetermined value, the flexible tube 10 is in the same state as every other short tube is rotated by the same angle. That is, the state shown in FIG. 3, in a state that only rotated 180 degrees first short pipe 12 and the third short pipe 16b from the state shown in FIG.

According to this embodiment, since the inclination directions of the joining surfaces are alternately changed in the straight pipe state, the respective short pipes are alternately rotated in the opposite direction by an appropriate same angle. Thereby, a required curvature can be easily obtained in a range from a straight pipe state to a maximum curvature in the same plane. Therefore, it is possible to cope with pipes of a plurality of desired curvature in one universal bends.

When a mark 30 for providing a predetermined curvature is provided on the outer surface of each short pipe as shown in FIGS. 4 and 5, for example, the short pipes are made identical by matching the marks 30. Since the angle can be rotated, a predetermined curvature can be obtained more easily.

In the flexible tube 10 shown in FIG. 4, the mark 30 includes a reference line 32 indicating a straight pipe state and a target line 34 indicating a predetermined curvature. The reference line 32 is provided, for example, in a straight line on all the short tubes. The target line 34 is provided, for example, on every other short pipe, in this embodiment, on the first short pipe 12 and the third short pipe 16b. The target line 34 is provided, for example, at a position where a plurality of curvatures required in advance can be obtained, that is, at a position shifted from the reference line 32 by a required angle in a required rotation direction. Although not shown, each target line may be provided with a number or the like that indicates a curvature, a radius of curvature, a bending angle, or the like.

[0028] Then, when the freely curved pipe 10 to a predetermined curvature, for example by rotating the short pipes as described above, combining a target line 34 of the reference line 32 and a predetermined curvature. For example, if the desired curvature is the target line 34a, in this embodiment, the target line 34a of the first short pipe 12 is set to the third short pipe 16a.
Combined with the reference line 32 of a, a target line of the third short pipe 16b 34
a may be adjusted to the reference line 32 of the third short pipe 16a and the second short pipe 14.

In the flexible tube 10 shown in FIG. 5, the mark 30 is represented by a reference point 36 and a target point 38. For example, the reference points 36 are provided at both ends of each short pipe, and the target points 3
8 is provided on the other end side of each short pipe. Also in this case, the reference point 36 and the target point 38 having a predetermined curvature (for example, the target point 3
8a), a predetermined curvature can be easily obtained. Also in this case, each target point 38 may be provided with a number or the like that indicates the above-mentioned curvature or the like.

It should be noted that the mark 30 is shown in FIGS.
However, the present invention is not limited to the shapes and arrangements shown in FIG.

In each of the above embodiments, the third short pipe 16
The while indicating that connects two continuously, the number of the third short pipe 16 is of course it can be changed as appropriate. However, also in this case, the short pipes are connected in such a manner that the inclination directions of the joining surfaces A1 and A2 are alternately different in a straight pipe state in which the pipe axes are coaxial.

In each of the above embodiments, the first short pipe 12
A rubber ring socket 28 is formed at one end of the first short pipe 12. The one end of the first short pipe 12 is appropriately changed in accordance with the pipe end of the first pipe to be connected. You may.

Further, in each of the above embodiments, the second short pipe 1
4, the other end of the second short pipe 14 is appropriately changed in accordance with the pipe end of the second pipe to be connected. Good.

Further, in each of the above-described embodiments, the connecting portion 18 to which each short pipe is rotatably connected to each other within the joint surface is formed continuously at the end of each short pipe. The method of forming the connection portion 18 can be changed as appropriate.

The connecting portion 18, for example, as shown in FIG. 6, it may be formed as each of the short pipe and a separate pipe fittings 40. The pipe joint 40 includes a first joint part 42 having the first engagement part 20 and a second joint part 44 having the second engagement part 22, and is formed by, for example, injection molding of a synthetic resin or the like. The first joint portion 42 and the second joint portion 44 are provided with openings 46 and 48 for receiving short tubes, respectively, and the short tubes are connected to the openings 46 and 48 by, for example, bonding. In this case, since straight pipes can be used as the short pipes, all of them need not be injection-molded as in the embodiment of FIG. 1, so that the manufacturing cost of the mold and the like can be reduced.

In each of the above embodiments, the first engaging portion 2
Although the rubber ring accommodating groove 24 is formed on the outer surface of the second engagement portion 22, the rubber ring accommodating groove 24 may be formed on the inner surface of the second engaging portion 22.

Further, the shapes of the first engaging portion 20 and the second engaging portion 22 of the connecting portion 18 are not limited to the above-described embodiments, but can be changed as appropriate. Generally, a universal joint structure rotatable through such an inclined joint surface is formed by injection molding because of its complicated shape and the like. As described above, the first engagement portion 20 and the second engagement portion 22 may be formed with a relatively simple structure by appropriately expanding the diameter of the end of the short pipe by the thermal secondary processing. In this case, the manufacturing cost can be further reduced.

In this embodiment, the second engaging portion 22 has a first tapered portion 5 whose diameter increases toward the distal end (open end).
0, and a second tapered portion 52 whose diameter decreases from the distal end of the first tapered portion 50 toward the open end, and which are inclined at a predetermined angle θ with respect to a plane B orthogonal to the tube axis b as a whole. You. The first engagement portion 20 has a diameter-enlarging portion 54 whose diameter increases toward the tip (open end) side, and a tip portion that extends from the tip of the diameter-enlarging portion 54 at a predetermined angle θ with respect to the tube axis a, for example. 56. Then, such a first engagement portion 2
0 and the second engagement portion 22 are engaged, the first engagement portion 20
The outer surface of the enlarged diameter portion 54 and the distal end surface of the distal end portion 56 are
The tip surface A1 of the first engagement portion 20 is in contact with the inner surface of the second taper portion 52 and the inner surface of the first taper portion 50 of the engagement portion 22 at a predetermined angle θ with respect to a surface B orthogonal to the tube axis a. Incline. The connecting portion 18 of the embodiment shown in FIG.
Similar to (2), while the inclination angle θ of the distal end surface A1 of the first engagement portion 20 is maintained by the second engagement portion 22, the first engaging portion 20 and the second engaging portion 22 , Tip surface A1
Can be relatively rotated within a joint surface having a joint surface. In addition,
In this embodiment, the rubber ring 26 is provided between the outer surface of the distal end portion 56 of the first engaging portion 20 and the inner surface of the second engaging portion 22 (near the boundary between the first tapered portion 50 and the second tapered portion 52). It is provided.

In each connection portion 18 of each embodiment described above, the first engagement portion 20 is formed on the other side of a short tube or the like.
In addition, the second engagement portion 22 is formed on one side of the short pipe or the like, but these may be formed on the opposite sides.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is an illustrative view showing a connection portion of the embodiment in FIG. 1;

FIG. 3 is an illustrative view showing the embodiment of FIG. 1 rotated to a maximum curvature;

FIG. 4 is an illustrative view showing a modified example of the embodiment in FIG. 1;

FIG. 5 is an illustrative view showing a modified example of a mark;

FIG. 6 is an illustrative view showing a modified example of a connection unit;

FIG. 7 is an illustrative view showing a modified example of a connection unit;

FIG. 8 is an illustrative view showing one example of a conventional technique;

FIG. 9 is an illustrative view showing another example of the related art;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Flexible bending pipe 12 ... 1st short pipe 14 ... 2nd short pipe 16 ... 3rd short pipe 30 ... Mark

Claims (2)

[The claims] 1. A freely bending pipe comprising three or more short pipes having a joint surface inclined with respect to a pipe axis in a straight pipe state and connected to each other continuously and rotatably within said joint surface, In the straight pipe state, the inclination direction of the joining surface was alternately changed,
A freely curved tube. 2. The flexible tube according to claim 1, wherein a mark for providing a predetermined curvature is provided on an outer surface of the short tube.