JP2009166456A - Manufacturing method of pipe fitting, manufacturing apparatus of pipe fitting - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of pipe fittings and a manufacturing apparatus of pipe fittings which exhibit a good productivity, yield products having a stable quality and easily cope with the situation where the thickness of a water-seal sheet wound on the pipe fitting is changed or the amount of the force to press the sheet against the pipe needs to be changed. <P>SOLUTION: In the manufacturing apparatus of pipe fittings 10 a core bar-sliding cylinder 29 is activated to insert a core bar 21 into a screwed pipe 3 around the inner surface of which a water-expansive sheet is attached. In the manufacturing apparatus of pipe fittings 10 then a core bar expanding cylinder 23 is activated to let the core bar 21 press the water-expansive sheet against the inner surface of the screwed pipe 3 and the screwed pipe 3 is rotated, as it stands. The core bar 21 presses the water-expansive sheet against the entire inner surface of the screwed pipe 3, as the screwed pipe 3 is rotated. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a method for manufacturing a pipe joint and an apparatus for manufacturing a pipe joint for connecting, for example, pipes used for protection of electric wires and cables.

Conventionally, pipes have been used to protect electric wires, cables, etc., but when such pipes are buried in the ground, it is necessary to ensure waterproofness at the connecting portions. For this reason, it is necessary to waterproof the pipe joint used for connecting the pipe bodies.

As such a pipe joint having a waterproof property, for example, a pipe having a water-stop sheet, such as a water expansion sheet that expands by absorbing moisture, is known on the inner peripheral surface of the pipe body. Yes. That is, by providing the sheet in the gap between the pipe joint and the pipe connected to the pipe joint, the sheet expands due to moisture that has entered from the outside during use, filling the gap between the pipe joint and the pipe body, This prevents moisture from entering the pipe from the gap with the pipe.

16A and 16B are views showing the pipe joint 50. FIG. 16A is a perspective view showing the appearance of the pipe joint 50, and FIG. FIG. 17 is a cross-sectional view showing a state in which the pipe joint 50 connects the protective pipes 51a and 51b.

The pipe joint 50 is obtained by attaching a water expansion sheet 55 to the inner peripheral surface of a cylindrical spiral grooved pipe 53. The pipe joint 50 is provided with a water expansion sheet 55 at a contact portion with the protective pipes 51a and 51b since protective pipes and the like connected from both ends thereof are inserted. Since the pipe joint 50 has the spiral groove 54 on the inner peripheral surface, the water expansion sheet 55 is attached along the inner peripheral surface irregularities of the pipe joint 50 formed by the spiral groove 54.

In order to connect the protective pipes 51a and 51b by the pipe joint 50, for example, the following may be performed. That is, from one end of the pipe joint 50, the protective pipe 51a is inserted while screwing the protective pipe 51a and the spiral groove 54 of the pipe joint 50, and screwed to the other end.

Next, the end of the protective pipe 51b is abutted with the end of the protective pipe 51a, and the pipe joint 50 is rotated in the reverse direction. That is, the pipe joint 50 is rotated in a direction in which the pipe joint 50 is detached from the protective pipe 51a and in a direction in which the pipe joint 50 is screwed in the protective pipe 51b. The connection is completed when the butted portion 52 of the protective piping 51a, 51b comes to the approximate center of the pipe joint 50.

The protection pipes 51a and 51b and the pipe joint 50 connected in this manner have the water expansion sheet 55 disposed in the gap between the connection portions. Therefore, when moisture enters from the outside, the water expansion sheet 55 is It expand | swells and the clearance gap between the pipe joint 50 and protective piping 51a, 51b can be filled, and the penetration | invasion of the water | moisture content in the protective piping 51a, 51b can be prevented.

As such a pipe joint, for example, there is a pipe joint in which a water expansion sheet is attached to a surface of the connection portion of the pipe body facing the pipe body (Patent Document 1).

In addition, after disposing a water expansion sheet on the inner peripheral surface of a cylindrical body member formed in advance, the core material was press-fitted while rotating into the main body member, and the inner peripheral surface of the main body member was provided. There exists a manufacturing method of a pipe joint which fixes a water expansion sheet in a body member with an adhesion ingredient (patent documents 2).
JP 2003-278773 A Japanese Patent No. 3678742

However, the pipe joint described in Patent Document 1 has a problem in that quality variation tends to occur because the water expansion sheet is manually attached to the inner peripheral surface of the main body member. In particular, when the main body member has a spiral groove, it is necessary to stick the water expansion sheet along the spiral groove, which is difficult to work, and there is a risk of poor attachment or leakage of the connection due to this. There is a problem that there is.

Further, in the method of manufacturing a pipe joint described in Patent Document 2, the pipe joint can be easily manufactured. However, in order to press-fit the core material into the main body member, the pressing force that presses the water expansion sheet to the inner peripheral surface of the main body member. There is a problem that cannot be changed. That is, in this manufacturing method, the pressing force of the water expansion sheet is uniformly determined by the outer diameter of the core mold member, the inner diameter of the main body member, and the thickness of the water expansion sheet. For this reason, there is a problem that the pressing force of the water expansion sheet changes due to the dimensional error and deformation of the main body member, the thickness error of the water expansion sheet, and the quality is not stable. Furthermore, such a method of press-fitting the core material into the main body member cannot cope with design changes such as changes in the material and thickness of the water expansion sheet, and there is a problem that the core material needs to be recreated.

In addition, core materials having different external shapes are required for changing the pressing force. For this reason, when handling the water expansion sheet | seat from which thickness differs, there exists a problem that it is necessary to prepare the core type material of a different size for every thickness. Furthermore, since the core material is press-fitted inwardly from the end of the main body member, the water expansion sheet is likely to be wrinkled or turned up inside the main body member, resulting in a quality problem.

In particular, when the main body member has a spiral groove, in order to press the entire water-expandable sheet, the core material is set in accordance with the number of groove pitches of the tubular body by the length corresponding to the pasting length of the sheet member. It is necessary to rotate it by the required number and insert it into the pipe joint, and then reverse it by the same number of rotations as it was inserted to return it to the base. As a result, compared to the insertion start portion, the insertion end portion has a smaller number of rotations for pressing by the number of movements of the spiral groove necessary for insertion of the core material, and ensures the adhesion of the insertion end portion. As a result, the pressure is more than necessary. Furthermore, if the rotational speed of the core material is increased, the sheet member may not be pressed uniformly, so that it is difficult to increase the attaching speed and the productivity is poor. Furthermore, if the inner peripheral surface of the main body member is smooth or a spiral groove, it is possible to press-fit the core material, but in the bellows tube or the like having independent grooves in which annular grooves are provided at regular intervals, in this manufacturing method, There is a problem that the water expansion sheet cannot be attached.

The present invention has been made in view of such problems, has good productivity, can obtain stable quality, and the thickness and material of the water-stop sheet to be attached to the pipe joint are changed. Or when it is desired to change the pressing force that presses the sheet against the pipe body, it has a pipe joint or a straight groove having not only a spiral groove but also an independent groove on the peripheral surface of the pipe body. It is an object of the present invention to provide a method for manufacturing a pipe joint and the like that can manufacture a pipe joint and a different type pipe joint.

In order to achieve the above-described object, the first invention provides a grooved tubular body having a spiral groove formed continuously in the tubular body or a plurality of annular grooves formed independently of the tubular body. On the other hand, the grooved tubular body is fitted into the grooved tubular body in which the sheet member is disposed along the inner peripheral surface of the grooved tubular body via the grooved tubular body and the sheet member. After inserting a plurality of pressing bodies having convex portions according to the groove shape of the surface in a state where the outer peripheral portions of the plurality of pressing bodies are reduced in diameter, the plurality of pressing bodies are respectively inserted into the circumferential surface of the grooved tubular body. The grooved tubular body and / or the plurality of pressing bodies are rotated while the diameter is expanded and brought into contact with the sheet member and the pressing body is pressed against the sheet member against the circumferential surface of the grooved tubular body. Or do not rotate or reciprocate at a certain angle, press The sheet member disposed on the inner peripheral surface of the serial grooved tube by adhering or bonding a manufacturing method of the pipe joint of manufacturing the pipe joint.

Here, the pressing body is a member such as a core bar for pressing the sheet member against the peripheral surface of the tubular body. The sheet member is a sheet-like member having a property of expanding when water is absorbed, such as a water expansion sheet. Moreover, a pipe means the cylinder used as the base material of the pipe joint and pipe joint to manufacture.

The number of the pressing bodies is not particularly limited as long as they can be structurally designed. However, it is desirable that the number of pressing bodies is usually 2 to 4 pressing bodies, and the grooved tube body and / or the plurality of pressing bodies are used. Instead of rotating the pressing body, the grooved tube body and / or the plurality of pressing bodies may be reciprocated at a predetermined angle in the circumferential direction of the grooved tube body.

In the above-described method for manufacturing a pipe joint, a linear pipe body is used instead of the grooved pipe body, and instead of a plurality of pressing bodies having convex portions in the pipe axis direction to be fitted thereto, in the pipe axis direction. A plurality of pressing bodies having linear portions can also be used. Here, the straight tubular body refers to a tubular body having an inner peripheral surface with no irregularities such as a groove or a main body having no irregularities on the inner peripheral surface of the pipe.

In addition, the adhesion of the sheet member arranged on the inner peripheral surface of the grooved tubular body can be performed by heating, and the adhesiveness can be improved by heating and performing the bonding without heating. Bonding can be easily performed in a short time. The sheet member can be attached to the tube by pressure bonding without using an adhesive. For example, by pressing a sheet member in which a polyester fiber or the like is mixed with a woven or non-woven fabric containing water-expandable fibers with a heated pressing body, the polyester fiber is plasticized and embedded in a tubular resin, and the sheet member and the tubular body Resin can be crimped. Here, the polyester fiber has the same effect as the hot melt adhesive.

Thus, the sheet member can be attached to the tube body by pressing, either by bonding or by pressure bonding. Of course, not only applying an adhesive to the outer surface of the sheet member, but also mixing and pressing can be performed simultaneously by mixing polyester fibers in the water expansion sheet member and heating and pressing. In the case of pressure bonding, the polyester fiber mixed in the sheet member is partially melt-plasticized and fused to the tubular resin.

In this way, when the sheet member includes polyester fiber or the like, when the sheet member is released from the pressure, the sheet member is slightly shaped from the shape formed in accordance with the shape of the peripheral surface of the tubular body at the time of pressing. Although it tries to recover to the shape before pressing, the melted polyester fiber has the effect of fixing and restraining the sheet member at the position at the time of pressing. is there.

According to the first invention, the plurality of pressing bodies that press the sheet member to the tubular body are inserted to the peripheral surface of the tubular body without contacting the sheet member or the like in a reduced diameter state, and then the plurality of pressing bodies. Increases the diameter and starts pressing the sheet member arranged so that the plurality of pressing bodies do not move to the circumferential surface of the grooved tube, so that the insertion speed can be increased. Further, since the plurality of pressing bodies press the entire length of the sheet member against the tubular body, for example, when pressing a pair of pressing bodies against the opposing portions of the circumferential surface of the tubular body, the tubular body is rotated at least 1/2 turn or 1, Although it is sufficient to rotate by a small number of rotations of two rotations, more rotation may be required depending on the type of adhesive and the bonding conditions. In addition, since the plurality of pressing bodies are expanded in diameter after the pressing body is inserted and the plurality of pressing bodies perform pressing, not only a tubular body having a spiral groove or a tubular body without a groove but also an annular groove having a constant interval. The sheet member can also be attached to the inner peripheral surface of the tubular body having the independent groove provided in.

In addition, since the insertion and pressing of the pressing body are completely separate processes, the pressing force can be freely adjusted, and even when handling a sheet member having a different thickness, without replacing the pressing body, The same pressing body can be used. Furthermore, if the sheet member is bonded by heating the sheet member or the pressing body, the sheet member can be formed and bonded reliably and easily, and a hot melt adhesive can be used, thereby shortening the bonding time. By using a sheet member containing a polyester fiber having thermocompression bonding, the tube body and the sheet member can be bonded without using an adhesive.

In the first aspect of the invention, when the sheet member is disposed on the grooved tubular peripheral surface, it is desirable that the sheet member does not move relative to the grooved tubular peripheral surface. In this case, it is desirable to temporarily fix with an adhesive, but it is also possible to fix using a fixing means such as a pin. Needless to say, when fixing with a fixing member such as a pin, it is necessary to remove the fixing member such as a pin after the manufacture of the pipe joint. In addition, when temporarily fixing with an adhesive, it is only necessary to prevent the sheet member from moving, so it may be temporarily fixed to at least a part of the peripheral surface of the tubular body, and the entire sheet member can be temporarily fixed, It is not always necessary to temporarily fix the whole, and whether the temporary fixing is a part or the whole can be appropriately selected as necessary.

In addition, when manufacturing a pipe joint only by adhesion | attachment, it is necessary to apply | coat an adhesive so that the whole sheet | seat member may be covered, but when manufacturing a pipe joint by crimping | bonding, the adhesive should just apply | coat to the extent which can be temporarily fixed. . Moreover, when manufacturing a pipe joint using the effect of both adhesion | attachment and crimping | bonding, it is necessary to apply | coat an adhesive agent to the whole surface. Thus, the application of the adhesive can be changed according to the manufacturing method of the pipe joint.

For this reason, it is excellent in productivity and workability. Furthermore, the sheet member can be attached to both types of pipe joints of independent grooved pipes and spiral grooved pipes only by changing the pressing body, and both types of pipe joints can be manufactured. Since there is no press-fitting step, there is no turning of the sheet member and the pressing force can be adjusted, and therefore a method of manufacturing a pipe joint capable of obtaining stable quality even if the thickness and material of the sheet member are different is provided. be able to.

The second invention includes a plurality of pressing bodies that press the inner peripheral surface of the tubular body, a moving unit that moves the plurality of pressing bodies into and out of the tubular body, and the diameter of the plurality of pressing bodies is increased. A diameter expanding means for pressing the plurality of pressing bodies against the inner peripheral surface of the tubular body; and a rotating means for rotating the tube body and / or the plurality of pressing bodies, wherein the moving means is the plurality of the plurality of pressing bodies. The pressing body is moved into the tube body, the plurality of pressing bodies are expanded by the diameter expanding means, and the plurality of pressing bodies are pressed against the inner peripheral surface of the tube body by the rotating means. The pipe joint manufacturing apparatus is applicable to any of an independent grooved pipe, a spiral grooved pipe, and a straight pipe body, wherein the pipe body and / or the plurality of pressing bodies are rotated.
A third invention includes a plurality of pressing bodies that press the inner peripheral surface of the tubular body, a moving unit that moves the plurality of pressing bodies into and out of the tubular body, and the diameter of the plurality of pressing bodies is increased. Diameter increasing means for pressing each of the plurality of pressing bodies on the inner peripheral surface of the tubular body, and the moving means moves the plurality of pressing bodies to the inside of the tubular body, and the plurality of diameter expanding means are used to Applicable to any of independent grooved pipes, spiral grooved pipes, and linear pipes characterized by expanding the diameter of the pressing body and pressing the plurality of pressing bodies against the inner peripheral surface of the tubular body. This is a manufacturing apparatus for a simple pipe joint.

In the second and third inventions, the plurality of pressing bodies are preferably 2 to 4 pressing bodies.

According to the second invention, the plurality of pressing bodies that press the sheet member against the tubular body are inserted to the peripheral surface of the tubular body without contacting the sheet member or the like in a reduced diameter state, and then the plurality of pressing bodies. Increases the diameter and starts pressing the sheet member arranged so that the plurality of pressing bodies do not move to the circumferential surface of the grooved tube, so that the insertion speed can be increased. Further, since the plurality of pressing bodies press the entire length of the sheet member against the tubular body if the length of the pressing body is made longer than the sheet member length by a predetermined amount, for example, the pair of pressing bodies are pressed against the opposing portions of the peripheral surface of the tubular body. In this case, if the adhesive and pressing conditions are appropriately selected, the tube body may be rotated at least 1/2, and the rotation may be performed a predetermined number of times as necessary.
Further, according to the third invention, the sheet member can be configured so that the pressing body can press the entire peripheral surface of the tubular body after the diameter of the pressing body of the second invention is expanded, without the rotation of the pressing body and the reciprocation of a predetermined angle. Can be pasted.

Further, since the pressing is performed after the pressing body is inserted, the sheet member can be attached to the inner peripheral surface of the tubular body having the independent grooves provided with the annular grooves at regular intervals. Moreover, since the insertion and pressing of the pressing body are completely separate processes, the pressing force and the pressing amount can be adjusted freely, and the groove shape of the tubular body is constant even when handling sheet members having different thicknesses. If it is, the same press body can be used.

In addition, when the sheet member is arranged around the entire circumference of the tubular body and the end portion of the sheet member is butted, the butted portion of the sheet member becomes a water channel, and there is a possibility that water may invade from the sheet. The end of the member may be wrapped. If the manufacturing apparatus of the present invention is used, after wrapping the sheet member, first, at this position, only the wrap portion is pressed with a pressing body, and the thickness of the sheet member of the wrap portion is thinly formed into the shape of the peripheral surface of the tubular body. At the same time, the sheet member can be attached to the peripheral surface of the tubular body, and then the pipe joint can be rotated, and the entire periphery including the portion other than the wrap portion of the sheet member can be molded and pasted according to the peripheral surface of the tubular body. . As described above, the pipe joint manufacturing apparatus according to the present invention can be pressed without rotating the tube body while the pressing member is pressed against the sheet member, or can be pressed while rotating the tube body with respect to the pressing member. It is also possible. It should be noted that if the core bar is structured so as to be almost completely circular when the diameter is expanded, and the structure is such that the inner circumferential surface pressing body is brought into contact with the core metal, the rotational motion or the reciprocating motion at a predetermined angle can be omitted. it can. With this structure, the sheet member can be attached without rotating the pressing body.

For this reason, it is excellent in productivity, and it is possible to affix a sheet member to an independent grooved pipe, it is excellent in workability, and since there is no press-fitting process, a pipe joint that can obtain stable quality can be obtained. A manufacturing apparatus can be provided.

According to the present invention, productivity is good, stable quality can be obtained, and when the thickness of the water-stop sheet attached to the pipe joint is changed, or the sheet is pressed against the pipe body. It is possible to provide a method for manufacturing a pipe joint that can easily cope with a change in pressing force.

Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a diagram showing a pipe joint manufacturing apparatus 10 according to the first embodiment. FIG. 1 (a) is a configuration diagram of the pipe joint manufacturing apparatus 10, and FIG. FIG. 6 is a view of the pressing roller 15 as viewed in the H direction.

As shown in FIG. 1A, a pair of support portions 18 are provided on the base 30, and the shaft 14 of the rotating roller 11 is rotatably provided on the support portion 18. A motor 13 for driving the rotary roller 11 is provided on the base 30 at the side of the support portion 18. Grooves 12 are provided near both ends of the rotating roller 11. The shaft 14 is connected to a motor 13, and the rotating roller 11 can be rotated in both forward and reverse directions by the motor 13.

A tube holding cylinder 17 is installed above the rotating roller 11. The tube pressing cylinder 17 has a tube pressing rod 19, and the end of the tube pressing rod 19 is provided on the support portion 20. The shaft 16 of the pressing roller 15 is rotatably provided on the support portion 20. Therefore, the pressing roller 15 can be moved in the directions of arrows A and B in the drawing according to the operation of the tube pressing cylinder 17. The tube pressing cylinder 17 is attached to the base 30 by a gantry not shown.

As shown in FIG. 1B, each of the rotating roller 11 and the pressing roller 15 is composed of a pair of rollers, and the rollers are provided in parallel. The manufactured spiral grooved tube 3 is placed between a pair of rotating rollers 11. The pair of rotating rollers 11 rotate in the same direction (for example, the X direction in the figure). At this time, the pressing roller 15 also rotates in the same direction as the rotating roller 11 as the tube rotates.

A core metal mount 27 is provided on the base 30. A height adjustment bolt 32 is provided on the upper portion of the core metal mount 27, and the tip of the height adjustment bolt 32 is joined to the core metal arm 26. The height adjustment bolt 32 is for adjusting the height of the core metal arm 26 in the vertical direction. The height of the cored bar 21 to be described later can be adjusted by the height adjusting bolt 32. For this reason, when manufacturing pipe joints having different pipe diameters, the cored bar 21 is connected to the center position of each tubular body. Can be adjusted. The core metal arm 26 is provided with a core metal diameter increasing cylinder 23.

The cored bar diameter increasing cylinder 23 is provided with a pair of cored bar diameter increasing rods 25 (not shown), and the cored bars 21a and 21b as pressing bodies are removed via the cored bar diameter increasing rods 25, respectively. Provided possible. In other words, the pair of core bars 21a and 21b are provided with their opposite sides facing each other. The operation of the core metal diameter increasing cylinder 23 will be described later.

Since the core bars 21 a and 21 b can be detached from the core bar arm 26, the core bars 21 a and 21 b can be exchanged according to the type of the pipe joint 1. The shape of the core bars 21a and 21b is determined by the shape of the pipe joint 1 to be manufactured. That is, there is no groove-like unevenness on the inner peripheral surface of the pipe joint 1, that is, for the manufacture of the pipe joint 1 in which a linear pipe body is used, the pressing surfaces of the core bars 21 a and 21 b are also the inner peripheral surface of the pipe joint 1. Corresponding to the shape, it may be linear (no irregularities). In addition, when the inner peripheral surface of the pipe joint 1 has a groove-like unevenness, the shape of the core bars 21a and 21b may be an uneven shape corresponding to the inner peripheral surface uneven shape of the pipe joint 1, What is necessary is just to have the convex part 22 corresponding to a groove shape. Note that a heater (not shown) is provided inside the cored bar 21. Therefore, the temperature of the cored bar 21 can be adjusted.

When the pipe joint 1 has a groove on the inner peripheral surface, the shapes of the core bars 21a and 21b are mainly determined by the depth and pitch of the groove of the pipe joint 1. In other words, if the depth and pitch of the grooves of the pipe joint 1 are the same, the core bars 21a and 21b having the same shape can be used regardless of the thickness of the water expansion sheet 5 (sheet member) to be attached. Furthermore, if the groove pitches are the same, even if the inner diameters of the pipe joints 1 to be manufactured differ to some extent, they can be accommodated by the core bars 21a and 21b having the same shape.

Moreover, it is desirable that the core bars 21a and 21b are slightly longer than the length of the pipe body of the pipe joint 1 to be manufactured. (To be precise, when a sheet member is attached to the peripheral surface of the pipe body over the entire length of the pipe body, it is desirable that the length of the pipe body is longer than the length of the pipe by the moving distance at the time of molding. When the length of the expansion sheet 5 is shorter than the tube length, it is desirable that the length of the expansion sheet 5 is substantially the same as the length of the water expansion sheet 5 or the length of the water expansion sheet 5 plus the moving distance of the pressing body. If the entire length of the sheet member can be pressed at once, bonding or crimping can be performed with a small number of rotations of 1/2 or 1, 2 rotations (pressing body movement distance corresponding to a small number of rotations) by adjusting the pressing force, temperature, and rotation speed. It is also possible to do.

The base 30 is provided with a core metal sliding cylinder 29 and a guide rail 33, and the core metal rack 27 is provided so as to be movable on the guide rail 33. The guide rail 33 is disposed up to the vicinity of the support portion 18 of the rotating roller 11. In addition, a cored bar slide rod 31 of a cored bar slide cylinder 29 is provided on the cored bar mount 27, and a cored bar slide rod 31 of the cored bar mount 27 is connected thereto. Therefore, the metal core mount 27 can slide on the guide rail 33 in the directions of arrows E and F in the drawing according to the operation of the cylinder 29 for mandrel slide. That is, when the core metal pedestal 27 is slid, the core metal diameter increasing cylinder 23 and the core bars 21a and 21b provided on the core metal pedestal 27 also move in the directions of arrows E and F in the figure. .

A stopper 35 is provided on the guide rail 33 in the vicinity of the support portion 18 in order to stop the core metal rack 27 at an accurate position during the sliding operation of the metal core rack 27. The metal core 27 comes into contact with the stopper 35 and stops the sliding operation during the sliding operation in the direction of arrow E in the figure. For this reason, the stopper 35 is attached so that the position can be freely changed on the guide rail 33 according to the type of the pipe joint to be manufactured.

A limit switch (not shown) is provided near the stopper 35. The limit switch detects the position where the cored bar mount 27 is stopped by the stopper 35 when the cored bar 21 is slid in the direction of arrow E in the figure.

Here, the materials of the rotating roller 11 and the pressing roller 15 are not specified, but in order to suppress slipping with the pipe joint 1 to be processed, a material that is difficult to slip is preferable, and rubber, resin, or the like can be used. Moreover, although the motor 13 is not specified, a normal electric motor may be sufficient. Moreover, although the material of the metal cores 21a and 21b is not specified, a material that is easy to slide with the water expansion sheet 5 and is not easily deformed is preferable, and metal, resin, or the like can be used. In particular, since there are a plurality of core bars 21a and 21b, the contact (pressing) area with the water expansion sheet 5 increases. For this reason, if the core metal 21a, 21b and the water expansion sheet 5 do not slide well, the water expansion sheet 5 may be displaced on the peripheral surface of the pipe when the core metal 21a, 21b presses the water expansion sheet 5. is there.

Next, the operation of the core metal diameter increasing cylinder will be described. FIG. 2 is an enlarged view showing the vicinity of the core metal diameter increasing cylinder 23 and the core metals 21a and 21b. FIG. 2A shows a state where the cored bar diameter increasing rod 25 is housed in the cored bar diameter increasing cylinder 23 and the distance between the cored bars 21a and 21b is reduced (hereinafter, this state is referred to as a “reduced diameter” state). ), And FIG. 2B is a side view.

As shown in FIGS. 2A and 2B, a cored bar diameter increasing cylinder 23 is connected to the cored bar 26, and the cored bar is disposed on both sides in the vertical direction via a pair of cored bar diameter increasing rods 25. 21a and 21b are joined. Guides 24 are provided in the vicinity of both ends of the core bars 21a and 21b. The guide 24 is for maintaining the state in which the core bars 21a and 21b are perpendicular to the core bar diameter-enlarging rod without causing swinging or the like when the core bars 21a and 21b move in the vertical direction. A pipe (not shown) is provided inside the cored bar arm 26, and the cored bar diameter expanding cylinder 23 is operated by a fluid from the outside.

2 (c) and 2 (d), when the cored bar diameter increasing cylinder 23 is operated, the cored bars 21a and 21b move in the vertical direction with respect to each other (in the directions of arrows C and D in the figure). 2) (hereinafter, this state is referred to as an “expanded diameter” state), FIG. 2C is a front view, and FIG. 2D is a side view. As shown in FIG. 2C and FIG. 2D, the cored bar diameter-expanding cylinder 23 operates to reduce the diameter and expand the diameter of the cored bars 21a and 21b. In addition, the diameter expansion (reduction diameter) direction of the core bars 21a and 21b is not limited to the vertical direction. As long as the directions of the core bars 21a and 21b are opposed to each other, the core bars 21a and 21b may have left and right or a predetermined angle depending on the manufacturing conditions of the pipe joint.

Here, as the tube holding cylinder 17, the cored bar diameter increasing cylinder 23, and the cored bar sliding cylinder 29, an electric actuator or the like can be used in addition to a hydraulic cylinder and an air cylinder. As will be described later, the core metal sliding cylinder 29 does not apply an external force to the core metal rack 27 except during the sliding operation of the core metal rack 27. At this time, when an external force is applied to the cored bar mount 27 from other places, the cored bar mount 27 freely slides on the guide rail 33 without receiving a reaction force from the cored bar sliding cylinder 29. It is necessary to be in a state that can be performed (in the direction of arrow E and arrow F in FIG. 1). For this reason, it is desirable that the core metal sliding cylinder 29 is an air cylinder having a simple structure.

Further, the cylinder 23 for expanding the cored bar only needs to be able to easily adjust the pressing force of the cored bar 21 and keep the pressing force against the water expansion sheet 5 constant during the manufacture of the pipe joint 1. Is preferably a simple air cylinder. In this case, the maximum pressing force of the cored bar 21 can be adjusted by the supply air pressure. Further, by providing a relief valve in the core metal diameter increasing cylinder 23, the pressing force of the core metal 21 can be adjusted to be kept constant without being excessively high.

Moreover, the pipe joint manufacturing apparatus 10 has a control unit (not shown). The control unit is connected to various sensors and operating units provided in the pipe joint manufacturing apparatus 10 and controls the operation of the pipe joint manufacturing apparatus 10. In the following description, it is simply referred to as “control unit”.

Next, the operation of the pipe joint manufacturing apparatus 10 according to the present embodiment and the method for manufacturing the pipe joint 1 will be described. FIG. 3 is a diagram showing a state in which the water expansion sheet 5 is installed in the spiral grooved tube 3, FIG. 3 (a) is a perspective view of the spiral grooved tube 3, and FIG. 3 (b) is the spiral grooved tube 3. Sectional drawing and FIG.3 (c) are the figures which looked at the spiral grooved tube 3 from the axial direction.

First, as shown in FIG. 3, the water expansion sheet 5 as a sheet member is inserted into the inner peripheral surface of the spiral grooved tube 3 as a tubular body. The spiral grooved tube 3 is a tube in which a continuous spiral groove 7 is formed on the inner peripheral surface. The water expansion sheet 5 is previously rolled into a cylindrical shape slightly smaller than the inner diameter of the spiral grooved tube 3 so as to be accommodated in the spiral grooved tube 3 and inserted so as to be in contact with the inner peripheral surface of the spiral grooved tube 3. Is done. At this time, the water expansion sheet 5 is slightly longer than the inner peripheral length of the spiral grooved tube 3 so that the wrap portion 9 is generated in a part of the water expansion sheet 5.

Here, the wrap portion 9 refers to a portion where both ends of the water expansion sheet 5 overlap each other when the water expansion sheet 5 is rolled into a cylindrical shape. If the wrap portion 9 is not provided, a gap is generated between the water expansion sheets 5 after the pasting process, and there is a risk of water intrusion from there. In addition, it is necessary to wrap the wrapping direction of the wrap portion 9 in a direction in which no turning is caused by the rotation of the spiral grooved tube 3 in the pressing process by the core metal 21 described later. The direction in which no turning occurs is the rotational direction in which the end of the upper member of the wrap portion does not hit the pressing member during rotation, and the upper end of the wrap portion (the sheet on the inside of the tube) along the wrap portion. The direction is from the end) toward the lower end (the sheet end that is the outside of the tube).

It is desirable that at least one location of the water expansion sheet 5 is temporarily fixed to the spiral grooved tube 3 in a state where the water expansion sheet 5 is accommodated in the tube. In order to temporarily fix the water expansion sheet 5 to the spiral grooved tube 3, the entire circumference of the water expansion sheet 5 may be temporarily fixed to the inner peripheral surface of the spiral grooved tube 3 with an adhesive or the like. Only a part of the water expansion sheet 5 may be temporarily fixed to the inner peripheral surface of the spiral grooved tube 3.

For example, when only a part of the water expansion sheet 5 is temporarily fixed to the inner peripheral surface of the spiral grooved tube 3, an adhesive previously applied to the outer peripheral surface of the water expansion sheet 5 located in the lap portion 9 is used. Temporarily fix to the inner peripheral surface of the spiral grooved tube 3. In this case, a portion of the water expansion sheet 5 other than the temporarily-wrapped wrap portion 9 may have a gap with the inner peripheral surface of the spiral grooved tube 3, but the rounded water expansion sheet 5 is self-supporting. Therefore, it is not crushed in the spiral grooved tube 3 and can be maintained while maintaining a substantially cylindrical shape.

Protrusions 4 are provided at both ends of the spiral grooved tube 3. When the spiral grooved tube 3 is set on the rotating roller 11, the protrusion 4 is fitted into the groove 12 of the rotating roller 11, and the set position of the spirally grooved tube 3 is made constant. This is to prevent the spiral grooved tube 3 from being displaced on the rotating roller 11 during processing. It should be noted that the positions of the spiral grooved tube 3 and the rotary roller 11 can be matched, and other known methods can be used as long as no positional deviation occurs during the manufacture of the pipe joint. An adhesive is applied in advance to the outer peripheral surface of the inserted water expansion sheet 5 or the inner peripheral surface of the spiral grooved tube 3. Therefore, the water expansion sheet 5 is bonded along the spiral groove on the inner peripheral surface of the spiral grooved tube 3 by pressing the water expansion sheet 5 to the inner peripheral surface of the spiral grooved tube 3 by the cored bar 21 described later. Moreover, if the water expansion sheet 5 uses a thermocompression-bonding sheet, the water expansion sheet 5 can be bonded along the spiral groove on the inner peripheral surface of the spiral grooved tube 3.

In FIG. 3, the spiral grooved tube 3 is inserted with different water expansion sheets 5 from both ends of the spiral grooved tube 3. You may make it stick over (all inner peripheral surfaces).

Here, as the material of the water expansion sheet 5, it is only necessary to absorb water and expand, and for example, a water expansion nonwoven fabric or a sheet in which an expansion material is applied, or a sheet in which the expansion material itself is used is used. it can. The adhesive may be a general adhesive. For example, an adhesive such as a synthetic rubber type or a vinyl type can be used. When the cored bar 21 is heated, a hot melt adhesive should be used. You can also. Typical hot melt adhesives include polyester and polyamide adhesives.

In addition, the material of the spiral grooved tube 3 is not specified and can be used for both resin and metal. However, considering the cost, it is desirable to use resin. Resin is more preferable than metal. As a material of the spiral grooved tube 3, for example, polyethylene, general-purpose plastic, polypropylene, vinyl chloride resin, ABS resin, hard rubber, and the like can be used. These materials need to be appropriately selected depending on the purpose of use.

Next, the operation of the pipe joint manufacturing apparatus 10 will be described. FIG. 4 is a flowchart showing the operation of the pipe joint manufacturing apparatus 10, and FIGS. 5 to 12 are diagrams showing the manufacturing process of the pipe joint 1. In FIG. 4, when the pressing member is brought into contact with the entire peripheral surface of the pipe and the sheet member is formed, the pipe does not need to be rotated by the motor, so steps 108 and 109 are not necessary, and step 110 is a cored bar. This is a process that only returns the cylinder for expanding the diameter.

First, as shown in FIG. 5, the spiral grooved tube 3 in which the water expansion sheet 5 is installed is set on the rotating roller 11. At this time, the protruding portion 4 of the spiral grooved tube 3 is set so as to be aligned with the groove 12 of the rotating roller 11. Thereby, the set position of the spiral grooved tube 3 can always be made constant. The control unit of the pipe joint manufacturing apparatus 10 detects that the spiral grooved pipe 3 is installed by using a photoelectric sensor or the like (not shown), and detects whether the installation position is appropriate (step 101). Although details will be described later, when the spiral grooved tube 3 is set, the wrap portion 9 of the internal water expansion sheet 5 is set to be below or above the inner peripheral surface of the spiral grooved tube 3.

By arranging the wrap portion 9 at the pressing start position of the core bars 21a and 21b described later, the thickness of the wrap portion 9 can be made closer to the thickness other than the wrap portion 9, and it can be easily used as a pipe joint. it can. In the case where the water expansion sheet 5 is temporarily fixed inside the spiral grooved tube 3, only a part of the water expansion sheet 5 can be temporarily fixed inside the spiral grooved tube 3 or the water expansion sheet 5. The entire surface and the entire inner peripheral surface of the spiral grooved tube 3 may be temporarily fixed. Only a part of the water expansion sheet 5 may be temporarily fixed, for example, only the wrap portion 9 may be temporarily fixed.

As shown in FIG. 6, when the control unit confirms that the spiral grooved tube 3 has been set at an appropriate position, the control unit operates the tube pressing cylinder 17 and lowers the pressing roller 15 (arrow in the figure). A direction), the spiral grooved tube 3 is pressed by the pressing roller 15 (step 102). At this time, the tube pressing cylinder 17 detects the pressing position of the spiral grooved tube 3 of the pressing roller 15 and the pressing force at that time by means of a limit switch or a pressure sensor (not shown). It is confirmed that the pressing force is normal (step 103).

Next, as shown in FIG. 7, the control unit operates the core metal sliding cylinder 29. Along with this, the cored bar mount 27 and the cored bar diameter expanding cylinder 23 and the cored bars 21a and 21b, etc., moved in the E direction (step 104), and the cored bars 21a and 21b have spiral grooves. It is inserted into the tube 3. At this time, since the core bars 21a and 21b are in a reduced diameter state, the core bars 21a and 21b do not come into contact with the spiral grooved tube 3. When the core metal mount 27 moves to the position of the stopper 35 which is a preset stop position, the core metal sliding cylinder 29 stops operating (step 105). At this time, the control unit detects that the mandrel mount 27 has moved up to the stopper 35 with the aforementioned limit switch.

Next, as shown in FIG. 8, the control unit operates the cored bar diameter increasing cylinder 23 to increase the diameter of the cored bar arm 26 and the cored bars 21a and 21b attached thereto (step 106).

FIG. 9 is a cross-sectional view when the core bars 21a and 21b are expanded in diameter within the spiral grooved tube 3, and FIG. 9A is a diagram illustrating a state in which the core bars 21a and 21b are inserted. 9 (b) is a view showing a state in which the core metal 21 is expanded and the water expansion sheet 5 is pressed. As shown in FIG. 9 (b), when the core bars 21a and 21b are expanded in diameter, the water expansion sheet 5 inserted into the spiral grooved pipe 3 is moved to the inner periphery of the spiral grooved pipe 3 by the core bars 21a and 21b. Pressed against the surface. Here, the cored bars 21 a and 21 b have convex portions 22 corresponding to the concave and convex shapes formed by the grooves 7 on the inner peripheral surface of the spiral grooved tube 3. For this reason, the cored bars 21a and 21b press the water expansion sheet 5 along the grooves 7 on the inner peripheral surface of the spiral grooved tube 3.

Moreover, as above-mentioned, if the metal cores 21a and 21b are made longer than the length of the pipe joint 1 to be manufactured by the pressing distance of the metal cores 21a and 21b for adhesion or pressure bonding, the total length of the metal cores 21a and 21b Thus, the entire length of the spiral grooved tube 3 can be pressed. As described above, the lengths of the core bars 21a and 21b are preferably longer by the moving distance of the core bars 21a and 21b. However, even if the core bar is shortened or the length of the core bar is not provided with a pressing portion, Shaping may be possible by reversing and pressing the body, or by repeatedly pressing the body.

The heating temperature of the heater varies depending on the type of the water expansion sheet 5 and the adhesive, but the water expansion sheet 5 does not change in quality, and a range in which the adhesive has good adhesiveness may be appropriately selected. Often set to 210 ° C. If the temperature is higher than this, the water-expandable sheet 5 is altered, and if it is about 60 ° C. or lower, the adhesive effect of the adhesive cannot be sufficiently obtained.

If necessary, the core bars 21a and 21b can be heated to a set temperature by a heater provided in the core bars 21a and 21b. When heating the cored bars 21a and 21b, the heater can be preheated to a predetermined set temperature. In this case, the control unit can perform temperature control within a predetermined temperature range so that the core bars 21a and 21b are within the set temperature range. In addition, by heating the metal cores 21a and 21b, when the metal cores 21a and 21b press the water expansion sheet 5, the water to the uneven shape formed by the grooves 7 on the inner peripheral surface of the spiral grooved tube 3 is obtained. Since the expansion sheet 5 can be easily molded and the adhesiveness is improved, the two can be easily and reliably bonded. Further, when a hot melt adhesive is used for bonding the water expansion sheet 5 and the spiral grooved tube 3, bonding in a short time is possible.

Furthermore, if the water expansion sheet 5 of thermocompression bonding is used for the water expansion sheet 5, the water expansion sheet 5 and the spiral grooved tube 3 are pressure bonded by pressing the water expansion sheet 5 heated to a predetermined temperature with a pressing member. can do.

Further, the wrap portion 9 of the water expansion sheet 5 in the spiral grooved tube 3 is set so as to come below or above the spiral grooved tube 3. In this state, after the lap portion 9 of the spiral grooved tube 3 is pressed, the spiral grooved tube 3 is rotated. For this reason, the cored bar 21a or the cored bar 21b first presses the wrap portion 9. Thereby, the water expansion sheet 5 can be affixed uniformly on the inner peripheral surface of the spiral grooved tube 3, and the rotation of the spiral grooved tube 3 can be made constant.

The core metal diameter increasing cylinder 23 can adjust the pressing force as described above, and can adjust the pressing force with which the core bars 21 a and 21 b press the water expansion sheet 5. Further, the cored bar diameter-enlarging cylinder 23 can always press the water expansion sheet 5 with a constant force by the set pressing force. That is, even when the water expansion sheets 5 having different thicknesses are attached to the same spiral grooved tube 3, the same core bars 21a and 21b can be used.

Further, the cored bar diameter expanding cylinder 23 can press the water expansion sheet 5 with a pressing force suitable for the type of the water expansion sheet 5 according to the type of the water expansion sheet 5. Further, the pressing force with which the metal cores 21a and 21b press the water expansion sheet 5 varies also when pressing portions having different thicknesses such as the wrap portion 9 or due to deformation of the spiral grooved tube 3 or dimensional errors. The core metal diameter-enlarging cylinder 23 can always press the metal cores 21a and 21b against the water expansion sheet 5 with a constant force.

The cored bar diameter-expanding cylinder 23 is provided with a pressure sensor or the like (not shown), and the control unit detects the pressing force of the cored bars 21a and 21b (the pressure of the cored bar diameter expanding cylinder 23). When the pressing force of the core bars 21a and 21b falls within the set pressing force range, the controller drives the motor 13 to rotate the rotating roller 11 (in the direction of arrow X in the figure) as shown in FIG. Steps 107 and 108). Thereby, the spiral grooved tube 3 rotates between the rotating roller 11 and the pressing roller 15 (in the direction of arrow Y in the figure).
When the cored bar is designed so that the cored bar covers the entire inner circumference of the pipe when the diameter of the cored bar is expanded, a driving device for a rotating roller such as the motor 13 shown in FIG. 10 is unnecessary.

At this time, the mandrel slide cylinder 29 is completely free to operate in the axial direction (the direction of arrows E and F in the figure). In other words, the core metal sliding cylinder 29 not only applies an external force to the core metals 21a and 21b, but also does not apply a reaction force to the force received from the core metals 21a and 21b. Therefore, the core metal mount 27 can freely slide on the guide rail 33.

The core bars 21 a and 21 b are screwed into the spiral groove 7 of the spiral grooved tube 3. For this reason, as the spiral grooved tube 3 is rotated, the core bars 21a and 21b are fitted into the grooves 7 of the spiral grooved tube 3 via the sheet member. Try to move in the axial direction. On the other hand, the cored bars 21a and 21b can be slid freely in the axial direction (the direction of arrow E and arrow F in the figure) in the same manner as the cored bar mount 27. Accordingly, with the rotation of the spiral grooved tube 3, the core bars 21 a and 21 b (core bar mount 27) follow the spiral groove 7, and the axial direction of the pipe joint (for example, the arrow F in the drawing). Direction).

In addition, the rotation direction of the rotating roller 11 (spiral grooved tube 3) is not specified. When the spiral grooved tube 3 has the spiral groove 7 as in the present embodiment, the convex portion 22 of the cored bars 21a and 21b and the groove 7 on the inner peripheral surface of the spiral grooved tube 3 as described above. As the spiral grooved tube 3 rotates, the core bars 21a and 21b move in the axial direction of the spiral grooved tube 3 (in the direction of arrows E and F in the figure). In this case, the rotational direction of the spiral grooved tube 3 may be any direction as long as the wrap portion 9 of the spiral grooved tube 3 is not turned over. However, since there is a risk of interference between the cored bar arm 26 and the spiral grooved tube 3 during rotation, the cored bars 21a and 21b preferably move in the direction in which they are retracted backward (in the direction of arrow F in the figure). Thus, it is desirable to rotate the spiral grooved tube 3.

The direction in which the wrap portion 9 of the spiral grooved tube 3 is not turned is a rotational direction in which the core bars 21a and 21b do not ride on the upper end (inside the tube body) of the wrap portion 9 and do not come into contact. Along the portion 9, the upper end of the wrap portion 9 (the end of the water expansion sheet 5 that wraps inside the tube) to the lower end (the end of the water expansion sheet 5 that wraps outside the tube) It is the direction toward.

FIG. 11 is a diagram showing the relationship between the wrapping direction of the wrap portion 9 and the rotation direction of the spiral grooved tube 3. FIG. 11A is a front view of the spiral grooved tube 3, and FIG. FIG. 3 is an enlarged view of a wrap portion 9. As shown in FIG. 11, the spiral grooved tube 3 rotates in the arrow Z direction in the figure in a state where the core bars 21 a and 21 b press the lap portion 9. The wrap portion 9 wraps so that the inner sheet end portion 37 is on the upper side and the outer sheet end portion 39 is on the lower side, and a step 38 is formed by the inner sheet end portion 37. That is, the inner sheet end portion 37 is a sheet end portion on the side exposed to the core bars 21a and 21b.

The rotation direction in which the water expansion sheet 5 is not turned is a direction in which the core bars 21 a and 21 b do not run over the step formed by the inner sheet end portion 37 of the wrap portion 9. The direction in which the core bars 21a and 21b do not run over the step formed by the inner sheet end portion 37 of the wrap portion 9 is the rotational direction in which the spiral grooved tube 3 moves in the arrow Z direction in the figure. That is, the core bars 21 a and 21 b start pressing the water expansion sheet 5 from the inner sheet end portion 37 of the water expansion sheet 5, descend the step 38, and press the outer sheet end portion 39. For this reason, the core bars 21a and 21b do not ride on the step 38 and do not hit the step 38. In addition, what is necessary is just to make it into the rotation direction opposite to the said Z direction with the rotation direction which the water expansion sheet 5 does not turn over when fixing the spiral grooved pipe | tube 3 and rotating the metal cores 21a and 21b.

The rotating roller 11 is rotated by a preset number of rotations by a timer or an encoder (not shown). The set number of rotations needs to be at least the number of rotations of the spiral grooved tube 3 to make 1/2 rotation. This is because the core bars 21a and 21b press the inner circumferential surface of the spiral grooved tube 3 over the entire circumference. The actual number of rotations may be appropriately determined in consideration of the adhesiveness and pressure-bonding property of the adhesive.

FIG. 12 is a cross-sectional view showing a state in which the spiral grooved tube 3 is rotated once in a state where the core bars 21 a and 21 b press the water expansion sheet 5. As shown in FIG. 12, the water expansion sheet 5 on the inner circumferential surface is pressed along the spiral groove 7 on the inner circumferential surface by the rotation of the spiral grooved tube 3 over the entire circumference. Moreover, the core bars 21a and 21b and the spiral grooved tube 3 are screwed together. For this reason, when the spiral grooved tube 3 rotates, the core bars 21 a and 21 b move by one pitch of the groove 7 from the initial pressing position relative to the spiral grooved tube 3. FIG. 12 shows a state where the core bars 21a and 21b have moved in the direction of retracting backward (in the direction of arrow F in the figure).

When the rotation roller 11 finishes rotating at the set number of rotations, the control unit stops the motor 13 and operates the cored bar diameter increasing cylinder 23 to reduce the diameters of the cored bars 21a and 21b, as shown in FIG. The pressing by the core bars 21a and 21b is finished (steps 109 and 110).

When the control unit detects that the core metal diameter increasing cylinder 23 has been returned to the original position (reduced diameter state) by a limit switch or the like (not shown), the core metal sliding cylinder 29 and the tube body pressing cylinder 17 are respectively operated. To return to the original position (step 111). Accordingly, the cored bar 27 returns to the original position (in the direction of arrow F in the figure), the pressing roller 15 rises (in the direction of arrow B in the figure), and releases the pressing of the spiral grooved tube 3. In this way, the pipe joint 1 in which the water expansion sheet 5 is pasted on the inner peripheral surface of the spiral grooved pipe 3 is manufactured.

The manufacture of the pipe joint 1 is completed by detecting that the core metal sliding cylinder 29 and the tube body pressing cylinder 17 are in their original positions by a limit switch or the like (not shown). After the pipe joint 1 that has been manufactured is removed, the spiral grooved pipe 3 is newly set as necessary, and the same operation is repeated to manufacture the pipe joint 1. The above operation is controlled by the control unit. As the control unit, a limit switch, a photoelectric sensor, a pressure sensor, a timer, a temperature sensor, and the like may be configured by relay control, and a CPU is used as the control unit. Control may be performed by operating a program. Further, in the manufacture of these pipe joints 1, the setting and pressing of the tube body to the manufacturing apparatus, the insertion of the core metal into the tube body, the pressing of the sheet member by the core metal, the operation of the motor for rotating the tube body, etc. Although it can be performed automatically, it can also be performed manually while checking each operation.

Thus, according to the pipe joint manufacturing apparatus 10 concerning this Embodiment, the pipe joint 1 which has the water expansion sheet 5 in an internal peripheral surface can be manufactured easily. Even if the pipe joint 1 has the spiral groove 7 on the inner peripheral surface, the water expansion sheet 5 can be attached along the groove 7. Further, if at least a part of the water expansion sheet 5 is temporarily fixed to the inner peripheral surface of the spiral grooved tube 3, the water expansion sheet 5 does not move in the spiral grooved tube 3. Can be done.

The core bars 21a and 21b that press the water expansion sheet 5 can adjust the pressing force, and can always press with a constant pressure. For this reason, a stable quality can always be obtained without being influenced by the dimensional accuracy of the spiral grooved tube 3. Further, even when the wrap portion of the water expansion sheet 5 is pressed to a predetermined thickness or when a water expansion sheet having a different thickness is attached, it is not necessary to replace the core bars 21a and 21b. , 21b allows the affixing operation to be performed with an appropriate pressing force according to the type and thickness of the water expansion sheet, so that the mandrel replacement operation is reduced and there is no need to arrange a large number of mandrel. Good workability.

The core bars 21a and 21b that press the water expansion sheet 5 can be heated to adjust the temperature. For this reason, when the cored bar 21a, 21b presses the water expansion sheet 5, it becomes easy to form the water expansion sheet 5 into the uneven shape formed by the grooves 7 on the inner peripheral surface of the spiral grooved tube 3. In the case where the water expansion sheet 5 contains a thermoplastic resin, the water expansion sheet 5 can be reliably molded, so that a high-quality pipe joint 1 can be obtained. In addition, it is desirable that the water expansion sheet 5 and the spiral grooved tube 3 be bonded by heating, but if heated, the bonding can be performed easily and reliably. Furthermore, since a hot melt adhesive can be used, the bonding time can be shortened.

Further, the core bars 21a and 21b press only a part of the inner peripheral surface of the pipe joint of the water expansion sheet 5, and when the water expansion sheet 5 is pressed, no force is applied in the axial direction of the spiral grooved tube 3, Since the rotation direction of the spiral grooved tube 3 when the gold 21a, 21b presses the water expansion sheet 5 is a direction in which the water expansion sheet 5 is not turned up, the pressing of the water expansion sheet 5 by the core bars 21a, 21b Sometimes, the water expansion sheet 5 is not peeled off or turned up, and there is no defect.

Further, in order to attach the water expansion sheet 5 to the entire inner peripheral surface of the spiral grooved tube 3, the spiral grooved tube 3 may be rotated at least 1/2 turn. For this reason, since the bonding time of the water expansion sheet 5 to the spiral grooved tube 3 is extremely short, the pipe joint 1 can be produced with high productivity.

Moreover, even when it has an independent groove | channel in the internal peripheral surface of the spiral grooved pipe 3, the water expansion sheet 5 can be reliably affixed along the independent groove | channel of the spiral grooved pipe 3 internal peripheral surface.

In the present embodiment, the case where two core bars 21 and 21b are used is shown, but the number of core bars 21 is not limited to this. For example, FIG. 14 shows an example in which four metal cores 21a, 21b, 21c, and 21d are provided, and FIG. 14 (a) is a diagram showing a reduced diameter state, and FIG. ) Is a diagram showing a state in which the diameter has been expanded.

As shown in FIG. 14A, the core bars 21a and 21b are provided to face each other (in the vertical direction in the figure). The core bars 21c and 21d are provided opposite to each other (left and right direction in the figure) and in a direction perpendicular to the core bars 21a and 21b. Between the core bars 21a and 21b, a core bar diameter increasing cylinder 23a and a guide 24a are provided. Further, a cored bar diameter increasing cylinder 23b (not shown) and a guide 24b are provided between the cored bars 21c and 21d.

That is, by operating the core bar diameter increasing cylinders 23a and 23b, the core bars 21a, 21b, 21c and 21d can be expanded in diameter as shown in FIG. If four cored bars are used, the inner peripheral surface of the pipe is pressed in a state where the diameter of each cored bar is increased. Therefore, the entire inner circumference of the pipe can be pressed by rotating the pipe at least 1/4. . Therefore, a pipe joint manufacturing apparatus with higher production efficiency can be obtained. Although the number of the core bars 21 is not limited, it is desirable that the number of core bars 21 can be set so as to be opposed to each other. Or it is desirable to use four. Moreover, each core metal does not necessarily need to be the same size. In addition, when a water expansion sheet is attached to the entire inner surface of the pipe joint by only pressing a plurality of core bars without rotating the core bar (when the entire inner peripheral surface of the pipe joint can be covered only by pressing the core bar) ), The core metal movement timing at the expansion and contraction diameter, the stop position at the diameter reduction (distance of the joint center) so that the core metals do not collide with each other when the core diameter expands or contracts It is necessary to change so that the core does not collide. For example, referring to FIG. 14, in FIG. 14, the movement timing of the mandrel when the core bars 21a and 21b in the vertical direction and the core bars 21c and 21d in the left and right direction are expanded and contracted, and the stop position when the diameter is contracted are shown. It should be different. In addition, since the cored bar is not rotated to attach the water expansion sheet, it is not expected to move in the pipe axis direction of the mandrel along with the rotation, so the length of the cored bar is equal to the length of the piped joint. It is necessary to.

FIG. 15 is a view showing an independent grooved tube 43 having an independent groove 41, FIG. 15 (a) is a perspective view of the independent grooved tube 43, and FIG. 15 (b) is a drawing of the independent grooved tube 43 as a core metal 21a. It is sectional drawing which shows the state which 21b is pressing. As shown in FIG. 15A, the pipe joint 40 is obtained by attaching the sheet member 5 to the inner peripheral surface of the independent grooved pipe 43 having the independent groove 41. Here, the independent groove 41 refers to a plurality of annular grooves provided independently from each other in the tube axis direction.

According to the pipe joint manufacturing apparatus 10, the pipe joint 40 is manufactured by using the core bars 21 a and 21 b having the convex portions 22 corresponding to the independent grooves 41 even if the pipes 43 have the independent grooves 41. be able to. That is, as shown in FIG. 15 (b), the cored bars 21a and 21b having the convex portions 22 corresponding to the independent grooves 41 press the water expansion sheet 5 to the inner peripheral surface of the independent grooved tube 43, and this state When the independent grooved tube 43 is rotated, the water expansion sheet 5 can be attached along the independent groove 41 over the entire inner peripheral surface of the independent grooved tube 43.

Therefore, if only the shapes of the core bars 21a and 21b are changed, even the pipe joint 40 having the independent groove 41 can be used in the pipe joint 1 having the spiral groove 7 or other pipe joints having no groove. Even if it exists, it can manufacture similarly. When manufacturing the pipe joint 40 having the independent groove 41, the core 43a is not screwed with the spiral groove even if the independent grooved tube 43 is rotated when the water expansion sheet 5 is pressed by the core bars 21a and 21b. The gold 21a, 21b does not move in the pipe joint axial direction.

As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

For example, in the first embodiment, the cored bars 21a and 21b that are longer than the spiral grooved tube 3 are used, so that the cored bars 21a and 21b are spirally grooved while the spirally grooved tube 3 is rotated 1/2. Although the inner peripheral surface of the attached tube 3 could be pressed over the entire length, the core bars 21a and 21b shorter than the spiral grooved tube 3 may be used. That is, in the first embodiment, the core bars 21a and 21b are inserted into the spiral grooved pipe 3 until the core bars 21a and 21b overlap the entire length of the spiral grooved pipe 3, and then the water expansion sheet 5 is inserted. However, it is also possible to perform a pressing operation after inserting the core bars 21 a and 21 b shorter than the spiral grooved tube 3 into the spiral grooved tube 3.

For example, after inserting the core metal 21a, 21b shorter than the spiral grooved tube 3 into the groove 7 on the inner peripheral surface of the spiral grooved tube 3, the water expansion sheet 5 is pressed with the cored bars 21a, 21b, and then the spiral grooved As the tube 3 rotates, the core bars 21a and 21b and the spiral grooved tube 3 are screwed together, and the core bars 21a and 21b move over the entire length of the spiral grooved tube 3 while moving in the spiral grooved tube 3 by screwing. The water expansion sheet 5 can be pressed. In this case, the total length of the core bars 21 a and 21 b can be shorter than that of the spiral grooved tube 3, but the total length of the core bars 21 a and 21 b is preferably longer than the total length of the water expansion sheet 5.

In the embodiment described above, the spiral grooved tube 3 is rotated. However, the core bars 21a and 21b may be rotated, or both may be rotated. That is, the same effect can be obtained if the spiral grooved tube 3 and the core bars 21a and 21b rotate relatively. Further, instead of rotating the spiral grooved tube 3 and the cored bars 21a and 21b, at least one of the spirally grooved tube 3 and the cored bars 21a and 21b is reciprocated at a constant angle, so 3 The inner surface may be pressed. For example, if a pair of core bars 21a and 21b is used, the entire inner circumference of the spiral grooved tube 3 can be pressed by reciprocating about 90 degrees clockwise and counterclockwise, respectively. If 21b, 21c, 21d is used, the entire inner circumference of the spiral grooved tube 3 can be pressed by reciprocating about 45 degrees forward and reverse.

Here, if the size of the core bars 21a and 21b is increased to increase the pressing range of the inner surface of the spiral grooved tube 3 at the time of diameter expansion, the entire inner surface of the spiral grooved tube 3 is pressed at a smaller rotation angle. You can also. For example, if the core metal size is such that about 1/2 of the inner circumferential surface of the spiral grooved tube 3 can be pressed when the diameter of the cored bars 21a and 21b is increased, the spiral grooved tube 3 can be spiraled by rotating the spiral grooved tube 3 about 1/4. The entire inner circumference of the grooved tube 3 can be pressed.

In addition, although the manufacturing method and manufacturing apparatus of this invention are normally applied about the manufacturing method and manufacturing apparatus of a joint in any form of a joint of an independent grooved pipe, a spiral grooved pipe, and a linear pipe body. In addition to the above-mentioned joints, the present invention can also be applied to the manufacture of dissimilar pipe joints (joints for dissimilar pipe bodies) in which different types of pipes are connected to both ends of the joint.

In addition, the pipe is manufactured from only one side of the pipe joint using the method described in the present invention. In the case of a different type pipe joint, the sheet member is divided into two pieces from the end of the joint toward the joint center. In the case of pasting, by selecting the length of the pressing member, two sheets can be pasted at the same time, or by reversing the joint in the tube axis direction, the two parts can be pasted one by one. it can.

It is a figure which shows the pipe joint manufacturing apparatus 10, (a) is a figure which shows the structure of the pipe joint manufacturing apparatus 10, (b) is a H direction arrow directional view of the rotation roller 11 and the pressing roller 15. It is a figure which shows the structure of the metal cores 21a and 21b and the core metal diameter expansion cylinder 23 vicinity, (a) is a front view which shows the state which the metal cores 21a and 21b reduced in diameter, (b) is the metal cores 21a and 21b. The side view which shows the state which diameter-reduced, (c) is a front view which shows the state which core metal 21a, 21b expanded, (d) is the side view which shows the state where core metal 21a, 21b expanded. It is a figure which shows the state which installed the water expansion sheet | seat 5 in the spiral grooved tube 3, (a) is a perspective view of the spiral grooved tube 3, (b) is sectional drawing of the spiral grooved tube 3, (c) is a spiral The figure which looked at the grooved pipe 3 from the axial direction. The flowchart which shows operation | movement of the pipe joint manufacturing apparatus 10. FIG. The figure which shows the state which set the pipe 3 with a spiral groove in the pipe joint manufacturing apparatus 10. FIG. The figure which shows the state which the pressing roller 15 of the pipe joint manufacturing apparatus 10 pressed down the pipe 3 with a spiral groove. The figure which shows the state by which the metal cores 21a and 21b of the pipe joint manufacturing apparatus 10 were inserted in the pipe 3 with a spiral groove. The figure which shows the state which the metal cores 21a and 21b of the pipe joint manufacturing apparatus 10 pressed the water expansion sheet 5 in the pipe 3 with a spiral groove. FIG. 6 is a cross-sectional view showing a state where the core bars 21a and 21b press the water expansion sheet 5, and (a) is a diagram showing a state where the core bars 21a and 21b are inserted into the spiral grooved tube 3 with the diameter reduced; (B) is a figure which shows the state which core metal 21a, 21b expanded and pressed the water expansion sheet 5 to the pipe 3 with a spiral groove. The figure which shows the state which the rotation roller 11 of the pipe joint manufacturing apparatus 10 rotated. It is a figure which shows the state which rotated the spiral grooved tube 3 in the state which pressed the water expansion sheet 5 with the metal cores 21a and 21b, (a) is a front view of the spiral grooved tube 3, (b) is a lap | wrap part. 9 enlarged view. Sectional drawing which shows the state which the pipe | tube 3 with a spiral groove rotated in the state which the metal cores 21a and 21b pressed the water expansion sheet 5 to the pipe | tube 3 with a spiral groove. The figure which shows the state which manufacture of the pipe joint 1 of the pipe joint manufacturing apparatus 10 was completed. The figure which shows the case where it has the metal cores 21a, 21b, 21c, and 21d. It is a figure which shows the independent grooved pipe | tube 43 which has an independent groove | channel, (a) is a perspective view of the independent grooved pipe | tube 43, (b) shows the state which the metal cores 21a and 21b are pressing the independent grooved pipe | tube 43. Sectional drawing. It is a figure which shows the conventional pipe joint 50, (a) is a perspective view which shows the external appearance of the pipe joint 50, (b) is sectional drawing of the pipe joint 50. FIG. Sectional drawing of a pipe joint which shows the state which the pipe joint 50 connected protective piping 51a, 51b.

Explanation of symbols

1, 40 ... Pipe fitting 3 ... Spiral grooved tube 4 ... Projection part 5 ... Water expansion sheet 6 ... Projection 7 ... Groove 8 ... Step 9 ... ... Wrap part DESCRIPTION OF SYMBOLS 10 ... Pipe manufacturing apparatus 11 ... Rotary roller 12 ... Groove 13 ... Motor 14 ... Shaft 15 ... Pressing roller 16 ... Shaft 17 ... Tube body pressing cylinder 18 ········· Supporting portion 19 ··········· Rolling rod 20 ····························· Support portions 21a, 21b, 21c, 21d ...... Core metal diameter increasing rod 26 ......... Core metal arm 27 ......... Core metal mount 29 ......... Core metal slide cylinder 30 ......... Base 31 ......... Core metal slide rod 33 ......... Guide rail 35 ......... Stopper 37 ......... Inner sheet member 38 ......... Step 39 ......... Outer sheet member 41 ......... Germany Groove 42 ......... Groove 43 ......... Independent grooved pipe 50 ... ... Pipe fitting 51 ... ... Protective piping 52 ... ... Butt portion 53 ... ... Spiral grooved pipe 54 ... ... Spiral groove 55 ... ... Water expansion sheet

Claims (7)

For a grooved tube having a spiral groove formed continuously in the tube or a plurality of annular grooves formed independently of the tube,
In the inside of the grooved tube body in which the sheet member is disposed along the inner peripheral surface of the grooved tube body,
A plurality of pressing bodies having convex portions according to the groove shape on the surface of the grooved tubular body, which are fitted via the grooved tubular body and the sheet member,
After inserting the outer periphery of the plurality of pressing bodies in a reduced diameter state,
Expanding the diameter of each of the plurality of pressing bodies to the circumferential surface of the grooved tube, and contacting the sheet member;
Furthermore, while pressing the pressing body against the circumferential surface of the grooved tube against the sheet member,
The grooved tubular body and / or the plurality of pressing bodies are rotated or pressed to the inner peripheral surface of the grooved tubular body without rotating or reciprocating at a predetermined angle with respect to the circumferential surface of the tubular body. A method for manufacturing a pipe joint, wherein a pipe joint is manufactured by bonding or crimping the arranged sheet members. The method of manufacturing a pipe joint according to claim 1, wherein the plurality of pressing bodies are 2 to 4 pressing bodies. Instead of rotating the grooved tube and / or the plurality of pressing bodies,
The pipe joint according to claim 1 or 2, wherein the grooved pipe body and / or the plurality of pressing bodies are reciprocated at a predetermined angle in a circumferential direction of the grooved pipe body. Method. The pipe joint manufacturing method according to any one of claims 1 to 3, wherein a straight pipe body is used in place of the grooved pipe body, and a plurality of protrusions are provided in a pipe axis direction to be fitted therewith. A method of manufacturing a linear pipe joint, wherein a plurality of pressing bodies having straight portions in the tube axis direction are used instead of the pressing body. A plurality of pressing bodies that press the inner peripheral surface of the tubular body;
Moving means for moving the plurality of pressing bodies into and out of the tubular body;
Diameter expanding means for expanding the plurality of pressing bodies, and pressing each of the plurality of pressing bodies against the inner peripheral surface of the tubular body;
A rotating means for rotating the tubular body and / or the plurality of pressing bodies;
Comprising
The moving means moves the plurality of pressing bodies into the tube body, expands the plurality of pressing bodies by the diameter expanding means, and presses the plurality of pressing bodies against the inner peripheral surface of the tube body. However, the pipe body and / or the plurality of pressing bodies are rotated by the rotating means, and the pipe joint is applicable to any of an independent grooved pipe, a spiral grooved pipe, and a straight pipe body. Manufacturing equipment. A plurality of pressing bodies that press the inner peripheral surface of the tubular body;
Moving means for moving the plurality of pressing bodies into and out of the tubular body;
Diameter increasing means for expanding the plurality of pressing bodies, and pressing each of the plurality of pressing bodies over the entire inner peripheral surface of the tubular body;
Comprising
The moving means moves the plurality of pressing bodies to the inside of the tube body, expands the plurality of pressing bodies by the diameter expanding means, and each of the plurality of pressing bodies on the entire inner peripheral surface of the tube body. An apparatus for manufacturing a pipe joint that can be applied to any of an independent grooved pipe, a spiral grooved pipe, and a straight pipe body. The pipe joint manufacturing apparatus according to claim 5 or 6, wherein the plurality of pressing bodies are two to four pressing bodies.

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