JPH0737064B2 - Pipe making machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pipe manufacturing method for manufacturing a long spiral pipe having a predetermined diameter by continuously winding a synthetic resin strip in a spiral shape. Regarding the machine.

(Prior art) Recently, underground pipes such as aging sewer pipes are being rehabilitated by lining them with synthetic resin pipes. For this method, for example, a pipe manufacturing machine for manufacturing a synthetic resin pipe by continuously winding a synthetic resin strip in a spiral shape is used. The pipe making machine is arranged so as to face one end surface of the underground buried pipe to be rehabilitated, and the spiral pipe manufactured by the pipe making machine is directly inserted into the underground buried pipe. If such a pipe making machine is used, the work efficiency in rehabilitating the underground buried pipe will be significantly improved. In addition, since it is sufficient to transfer the coiled strip to the work site, there is no need to transfer the bulky synthetic resin pipe to the work site, and there is an advantage that the transfer cost can be reduced.

Such a pipe making machine is disclosed in, for example, Japanese Examined Patent Publication No. 62-13170.
It is disclosed in JP-A-72-20987.

The pipe manufacturing machine disclosed in Japanese Examined Patent Publication No. 62-13170 regulates the outer diameter of the spirally wound strip by a plurality of rollers when spirally winding the strip. , The strip is guided. Moreover, the diameter of the spiral tube to be formed is changed by making the conveying speed of the spirally wound belt-shaped member different from the speed of the spirally wound belt-shaped member. . In addition, JP-A-62-20987
The pipe-making machine disclosed in Japanese Patent Laid-Open Publication No. 9-242242 conveys a strip-shaped body along the inner peripheral surface of an existing pipe to manufacture a spiral tube while controlling the outer diameter of the spirally-wound strip-shaped body. It is composed.

In this way, the pipe-making machine disclosed in each of the publications is configured to regulate the outer diameter of the wound band-shaped body when the band-shaped body is spirally wound. For this reason, when a strip-shaped body is sequentially spirally wound and a load is applied to the strip-shaped body in the transport direction when the spiral tube is continuously manufactured, the strip-shaped body swells from between the rollers and the like. There is a risk. When manufacturing a long spiral tube, such a load is likely to be applied to the strip,
It is not easy to manufacture a long spiral tube having a predetermined diameter.

Further, Japanese Patent Publication No. 51-13503 discloses a spiral hose manufacturing device for rolling a plurality of rollers onto the inner peripheral surface of the hose material when the hose material is spirally wound to manufacture the hose. . However, this manufacturing apparatus manufactures a spiral hose by winding a soft hose material extruded from an extrusion die around a plurality of rollers so that a part of the material overlaps with each other. It cannot be wound. Therefore, the spiral hose manufacturing apparatus cannot manufacture the spiral tube used for rehabilitation of the buried tube.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems, and an object thereof is a pipe manufacturing method capable of easily manufacturing a long spiral pipe having a predetermined diameter with a strong propulsive force. To provide a machine. Another object of the present invention is to provide a pipe manufacturing machine which does not require complicated control and is easy to operate. Still another object of the present invention is to provide a pipe manufacturing machine that can easily manufacture spiral pipes having different diameters.

(Means for Solving the Problems) In the pipe manufacturing machine of the present invention, a band-shaped body having engaging portions on both side edges is spirally wound and adjacent engaging portions are engaged with each other to form a spiral pipe. A pipe manufacturing machine to be manufactured, each of which is rotatable and has a plurality of driven rollers arranged in a cylindrical shape with a predetermined spiral angle, and two driven rollers provided in parallel with the driven rollers. A pair of driving rollers for sandwiching the belt-like member and rolling the belt-like member to the driven rollers so that the belt-like members are contained therein, and a driving roller pair for conveying the belt-like member to the driven rollers. And a tension roller pair that rotates at a speed slower than the rotation speed of the drive roller, thereby achieving the above object.

(Example) Hereinafter, the present invention will be described with reference to Examples.

The pipe making machine of the present invention, as shown in FIG. 1 and FIG.
It has a rectangular parallelepiped frame body 10 and a mandrel portion 20 mounted in the frame body 10. The mandrel portion 20 is attachable to and detachable from the frame body 10. The frame 10 includes a top plate 11 and a bottom plate 12
The side plates 13 and 13 and the back plate 14 form a horizontally long rectangular parallelepiped, and the front side portion is open.
The mandrel portion 20 is formed by opening the frame body 10 from the front side opening portion.
It is inserted into the frame 10 and attached to the frame 10. Each side plate 13
Top plate 11 and bottom plate so that they can approach and separate from each other
It is slidably attached to 12 via a long hole.

The back plate 14 has a support shaft 15 for supporting the mandrel portion 20.
Is cantilevered almost horizontally.

The mandrel portion 20 has a plurality of pipe making rollers 21. The pipe-making roller 21 has a driven roller 21a arranged on a roller shaft 22 in a rotating device, and two drive rollers 21b fixedly fitted on the roller shaft 22. The roller shaft 22 that supports the driven roller 21a is installed between a disk-shaped front support plate 23 and a rear support plate 24 that are arranged at a predetermined interval.
A connecting pipe 26 is installed between the central portions of both support plates 23 and 24. The connecting pipe 26 penetrates the back side support plate 24, and a laterally elongated auxiliary plate 25 is fixed to the penetrating end portion. Arc-shaped notches 24a and 24a are formed at two axially symmetric positions of the rear support plate 24, and each notch 24a is formed.
The end of the auxiliary plate 25 is located opposite to. This auxiliary plate
Roller shafts 22a and 22a are installed between each end of 25 and the front support plate 23, respectively. Of these roller shafts 22a, the driven roller 21a is externally fitted to the back side half on the profile supply side, the drive roller 21b is externally fitted to the front side half, and the drive roller 21b is fitted to the other roller shaft 22a.
Only the outer circumference of the roller shaft 22a is fitted. The outer peripheral surface of the drive roller 21b is made of, for example, hard urethane rubber. Gears 27 and 27 (see FIG. 3) are externally fitted to the rear end of each roller shaft 22 to which the driving roller 21b is externally fitted.

The roller shafts 22 and 22a are arranged so as to have a cylindrical shape with a predetermined spiral angle.

The mandrel portion 20 having such a configuration is mounted in the frame body 10. The connecting pipe 26 of the mandrel portion 20 is inserted into the support shaft 15 in the frame body 10 from the auxiliary plate 25 side. At this time, the drive rollers 21b and 21b are positioned on the respective side portions in the horizontal direction. When the auxiliary plate 25 reaches the rear plate 14 of the frame body 10, the support shaft 15
Penetrates the connecting pipe 26, and a set screw 15a is attached to the tip of the connecting pipe 26 to fix the entire mandrel portion 20 to the support shaft 15. On all the tube-making rollers 21 of the fixed mandrel portion 20, a synthetic resin band 40 is spirally wound so as to include these tube-making rollers 21.

The side plates 13 and 13 of the frame body 10 are respectively provided with drive rollers 16a and 16a paired with the drive rollers 21b and 21b of the mandrel portion 20, respectively. Each drive roller 16a is
They are externally fitted and fixed to roller shafts 16b arranged in a box-shaped mounting member 17a. Each mounting member 17a is attached to each drive roller 1
It is parallel to 6a. On the outer peripheral surface of each drive roller 16a, a large number of annularly protruding fins 16c, 16c, ... Are arranged at predetermined intervals in the axial direction. Each fin 16
As will be described later, the c is fitted between the ridges 42 arranged on the back surface of the strip 40. The outer peripheral surface of the drive roller 16a between each fin 16c is knurled.

The rear end of each roller shaft 16b is connected to the output shaft of a hydraulic motor 16d supported by a mounting member 17a, and the drive roller 16a is rotated by rotationally driving the hydraulic motor 16d. A gear 16e is externally fitted to each roller shaft 16b between the hydraulic motor 16d and the drive roller 16a. Each gear 16e
Can be meshed with a gear 27 arranged coaxially with the drive roller 21b of the mandrel portion 20 which is paired with the drive roller 16a arranged coaxially.

The bottom surface of each attachment member 17a is attached to the lower end portion of the support plate 17b arranged along the inner surface of each side plate 13. Each mounting member 17a is rotatable along a plane orthogonal to the supporting plate 17b. The upper surface of the mounting member 17a is
It is attached to a piston rod 17e of a hydraulic cylinder 17d via a connecting member 17c. The hydraulic cylinder 17d is supported by a support plate 17b such that the advancing direction of its piston rod 17e is in the direction in which the mandrel portion 20 is disposed. Therefore, when the piston rod 17e of the hydraulic cylinder 17d advances, the mounting member 17a rotates around the portion supported by the lower end of the support plate 17b, and the mandrel portion 20 disposed in the frame body 10 is rotated. Approach. On the contrary, when the piston rod 17e retracts, the mounting member 17a is separated from the mandrel portion 20. Then, when the mounting member 17a approaches the mandrel portion 20, the driving roller 16a mounted on the mounting member 17a approaches each driving roller 21b of the mandrel portion 20, and the belt-shaped body 40 forms a pair of driving rollers 16a. It is nipped by a pair of driving rollers composed of the drive rollers 21b and 21b. Then, the drive roller 16
When a approaches the drive roller 21b of the mandrel portion 20, the gears 16a and 27 fitted on the roller shafts 16b and 22a mesh with each other. As a result, when the drive roller 16a disposed in the frame body 10 is rotated by the hydraulic motor 16d, the drive roller 21b on the mandrel portion 20 side is also rotated, and the strip-shaped body 10 sandwiched between the two is driven roller 21a. Are transferred so that they are transferred to each other.

Support plate for supporting the hydraulic cylinder 17d and the mounting member 17a
17b is rotatably arranged along the side plate 13. Therefore, the drive roller 16a supported by the mounting member 17a is tilted by the rotation of the support plate 17b. Then, the support plate 17b is rotated so that the drive roller 16a is parallel to the drive roller 21b of the mandrel portion 20 which is twisted at a predetermined spiral angle.

The upper side of one support plate 17b is bent into the frame body 10, and the support member 17 penetrating the upper plate 11 of the frame body 10 is bent at the bent portion.
f is installed. A mounting frame 18a is arranged on the supporting member 17f. A tension roller pair consisting of a driving tension roller 18b and a driven tension roller 18c is arranged in the mounting frame 18a. The driving tension roller 18b is supported in parallel with the driving roller 16a above the driving roller 16a attached to the lower part of the support plate 17b supporting the tension roller 18b, and the driven tension roller 18c is The driving tension roller 18b
And are rotatably supported in parallel with. The drive tension roller 18b is a hydraulic motor supported by the mounting frame 18a.
It is connected to the output shaft of 18d and is rotated by the drive of the hydraulic motor 18d. The driven tension roller 18c can be moved toward and away from the driving tension roller 18b by the hydraulic cylinder 18f supported by the mounting frame 18a.
It is supported.

Between the pair of tension rollers, there is a belt 40 made of synthetic resin.
Is transported. When the driven tension roller 18b approaches the driven tension roller 18c, the tension roller pair sandwiches the strip 40, and the driven roller 16a below the driven roller 16a and the driven roller 21 facing the driven roller 16a.
The band 40 is fed to and from a.

On the outer peripheral surface of the driving tension roller 18b, annular fins 18g, 18g, ... Which project in the radial direction are arranged at predetermined intervals in the axial direction. The fins 18g are fitted between the ridges 42 provided on the back surface of the band-shaped body 40, as described later. The outer surface of the driving tension roller between each fin 18g is knurled.

An encoder 19a for detecting the rotation of the driving tension roller 18b is arranged on the mounting frame 18a. The drive tension roller 18b is rotated by the pair of sprockets 1
It is transmitted to the encoder 19a by 9b and 19c and the chain 19d wound around these sprockets 19b and 19c.

The pipe manufacturing machine of the present invention manufactures, for example, a band 40 having a sectional structure as shown in FIG. 4 into a spiral pipe. The strip 41 is
A sheet portion 41 having a smooth surface, and T-shaped protrusions 42, 42 having a T-shaped cross section, which are arranged in parallel in the width direction on the back surface of the sheet portion 41 at a predetermined interval. On one side rear surface of the seat portion 41 in the width direction, a fitting protrusion 43 having a spherical tip end is provided.
The T-shaped ridges 42 are arranged in parallel. The fitting protrusion 43
At the tips of the T-shaped ridges 42 adjacent to each other, a locking portion 42a bent toward the fitting ridge 43 is formed. The other side portion of the seat portion 41 in the width direction is formed with the fitting protrusion 43.
Is stepped down so as to form an engagement step 44 capable of engaging one side portion 41a in the width direction, and is positioned on the back side by the thickness of the seat portion 41. In this portion, a fitting concave groove 45 that is bent to the back side is formed so that the fitting protrusion 43 formed on one side can be fitted. A ridge 45a having a T-shaped cross section is provided at the bent portion where the fitting groove 45 is formed so as to project to the back side. Engaging ribs 46 are formed at the side edges of the seat portion 41 that form the fitting recessed groove 45 in the width direction and extend while inclining toward the back side. The tips of the engaging ribs 46 are wound on the fitting projection 43 when the strip 40 is spirally wound and the adjacent fitting projections 43 are fitted into the fitting groove 45. T next to each other
It can be locked to the bent locking portion 42a of the mold ridge 42. Mating groove 4
At the time of fitting the fitting protrusion 43 into the fitting 5, an adhesive is applied to the fitting groove 45 of the strip 40.

The spiral pipe for lining the underground buried pipe is manufactured as follows using the pipe manufacturing machine of the present invention having such a configuration. First, on the ground, the mandrel portion 20 having an outer diameter corresponding to the diameter of the spiral tube to be manufactured is attached to the frame body 10. Each pipe-making roller has a predetermined spiral angle. Then, the support plates 17b to which the drive rollers 16a are attached are provided along the side plates 13 so that the drive rollers 16a arranged in the frame body 10 are parallel to the drive rollers 21b of the mandrel section 20, respectively. , Rotate each. When each drive roller 16a is in parallel with each drive roller 21b on the mandrel portion 20 side, each support plate 17b is fixed. At this time, the tension roller pairs 18b and 18b attached to the one support plate 17b
c is the lower drive roller 16 as the support plate 17b rotates.
It is inclined in parallel with a.

In such a state, in order to separate the driven tension roller 18c from the drive tension roller 18b, the hydraulic cylinder 18f is driven and each drive roller 16a in the frame 10 is driven.
The hydraulic cylinders 17d are respectively driven so as to separate them from the drive rollers 21b of the mandrel section 20. Next, the tip end of the synthetic resin strip 40, which is a spiral tube, is passed between the separated tension roller pairs 18b and 18c, and then the hydraulic cylinder 18f is driven to bring the tension roller pairs 18b and 18c close to each other. Drive tension roller 18
The hydraulic motor 18d is driven to rotate b. In this way, the strip 40 is fed while being sandwiched by the pair of tension rollers 18b and 18c, and the drive roller 16a which is separated from the belt 40 by the tension rollers 18b and 18c.
And the driven roller 21a. After the leading end of the strip 40 has passed, the hydraulic cylinder 17d is driven so that the drive roller 16a approaches the driven roller 21a and the drive roller 21b. At this time, the gear 16e externally fitted to the drive roller 16a meshes with the gear 27 externally fitted to the roller shaft 22a, and the rotational driving force of the drive roller 16a driven by the hydraulic motor 16d is applied to the roller shaft 22a. When transmitted, the drive roller 21b is rotationally driven.

In this way, the belt-shaped body 40 is fed by being sandwiched between the driving roller 16a and the driven roller 21a. The strip 40 is manually guided so as to be wound around a plurality of pipe-making rollers 21 (driving rollers 21a) forming the lower half circumference of the mandrel portion 20, and is fed between the other driving roller pair 16a and 21b. . Band
When the tip end 40 passes through the drive roller pairs 16a and 21b, the hydraulic cylinder 17d is operated to bring the drive roller pairs 16a and 21b close to each other. At this time, a gear (not shown) externally fitted to the drive roller shaft 16b and a gear (not shown) externally fitted to the roller shaft 22a mesh with each other and are driven by a hydraulic motor (not shown). The rotational drive force of the drive roller 16a is transmitted to the roller shaft 22a, and the drive roller 21b is rotationally driven. In this case, the driving tension roller 18b and the fins 18g and 16c arranged on the outer peripheral surfaces of both the driving rollers 16a.
Must be located between the ridges 42 and 43 on the back of the strip 40.

In this way, the pipe-making roller 21 around the lower half of the mandrel portion 20
The belt-like body 40 wound along the (driven roller 21a)
Are fed by being sandwiched between the drive roller pairs 16a and 21b. The belt-shaped body 40 is further guided while being wound around a plurality of pipe-making rollers 21 (following rollers 21a) constituting the upper half circumference of the mandrel portion 20, and is sandwiched at the beginning below the tension roller pairs 18b and 18c. Send to pair 16a and 21b. At this time, the fitting protrusion 43 of the belt 40 that has made a round is fitted in the fitting groove 45 of the newly supplied belt 40 near the contact portion between the driven roller 21a and the drive roller 21b. If the driving of each drive roller is continued in this state, a spiral tube is formed.

In this way, the hydraulic motors 16d and 18d are stopped at the time when the strip 40 is spirally wound for 2 to 3 turns, and the entire pipe making machine is installed in the manhole to which the ends of the buried pipes to be lined are connected. . If the manhole entrance is narrow, temporarily operate the hydraulic cylinder 18f to move the tension roller pair 18b and
Support member that is attached to the mounting frame 18a by separating 18c
It suffices to remove 17f from the support plate 17b, insert the frame body 10 in a portrait orientation, and reassemble it in the manhole.

In this way, the pipe making machine is installed at a predetermined position in the manhole, and the hydraulic motors 16d and 18d are driven again. As a result, the strip-shaped body 40 unwound from the strip-shaped coil disposed on the ground is spirally wound, and the frame body is formed as a spiral tube.
It is sequentially led out from the front side of 10 and introduced directly into the buried pipe to be lined.

At this time, the belt-shaped body 40 formed by the first drive roller pair 16a and 21b arranged symmetrically with respect to the support shaft 15 with respect to the drive roller 16a arranged below the tension rollers 18b and 18c.
Is set so as to be faster than the conveying speed of the belt-shaped body 40 by the tension roller pairs 18b and 18c, and therefore, between the first driving roller pairs 16a and 21b and the tension roller pairs 18b and 18c. Tension is applied to the band 40 portion. As a result, the belt-like body 40 is forcibly pressed against each driven roller 21a located between the first drive roller pair 16a and 21b and the tension roller pair 18b and 18c,
It is surely curved in an arc shape. Also, the tension roller pair
A second drive roller pair consisting of a drive roller 16a disposed below 18b and 18c and a drive roller 21b forming a pair with the drive roller 16a is provided with And 21a are set so as to be faster than the conveyance speed of the belt-shaped body 40, so that tension is applied to the belt-shaped body 40 portion between both drive roller pairs. As a result, the belt-like body 40 is forcibly pressed against the driven rollers 21a located between the pair of drive rollers, that is, the driven rollers 21a forming the upper half circumference of the mandrel portion 20, and is surely curved in an arc shape.

Here, the conveyance speed of the belt 40 by the tension roller pairs 18b and 18c, the second drive roller pairs 16a and 21b, and the first drive roller pairs 16a and 21b will be described. In the present invention, in order to apply tension to the strip 40 and forcibly wind it around the mandrel portion 20, the transport speed of the strip 40 by each of the roller pairs is set so as to have the speed difference as described above. . As a result, when the strip 40 is transported, a tensile force due to the difference in transport speed is applied to the strip 40. For example, when the drive rollers have the same outer diameter, the rotational speeds of the hydraulic motors, which are drive sources, are set differently, and the rotational speed of the hydraulic motor 16d that rotates the first drive roller pair 16a and 21b is set to When set to 10, the second drive roller pair 16a and 21b
When the rotational speed of the hydraulic motor (not shown) for rotating the belt 40 is set to 9 and the rotational speed of the hydraulic motor 18d for rotating the driving tension roller 18b is set to about 4 to 5, The desired tension is applied to the band 40,
40 is forcibly wrapped around the mandrel 20
Spaces between spirals having a predetermined diameter can be formed.

Further, it is preferable that the pipe making speed can be switched between two stages of high speed and low speed or in multiple stages, but in this case as well, the ratio of the above-mentioned number of revolutions is always kept constant.

The encoder 19a is used to detect and display the rotation of the driving tension roller 18b, and this display allows the operator to recognize the actual pipe-making speed.

The drive roller pair and the tension roller pair in the pipe manufacturing machine of the present invention are not limited to the above-described embodiments, but include various aspects as described below.

For example, the first drive rollers 16a and 21b in the above-described embodiment may be absent. In this case, from the tension roller pair 18b and 18c to the mandrel
A belt-shaped body extending up to 20 and extending up to the drive roller pair 16a and 21b disposed below the tension roller pair 18b and 18c.
Since the tension is applied to the 40 portion, the strip 40 is forcibly pressed against all the driven rollers 21a constituting the mandrel portion at once, instead of the two stages of the lower half circumference and the upper half circumference as in the above-described embodiment. To be done.

Further, the drive roller pair 16a does not exist below the tension roller pairs 18b and 18c, and only the driven roller 21a exists due to the fitting of the belt-shaped body 40. The drive roller pairs 16a and 21b similar to those in the above embodiment may be provided. In this case, the tension roller pair 18b and 18c circumscribes the lower part of the mandrel portion halfway to apply tension to the belt-shaped body 40 portion sandwiched by the drive roller pairs 16a and 21b. It is forcibly pressed against each driven roller 21a forming the lower half circumference of the portion 20. Even with such a configuration, the strip 40 is finally forcibly pressed against the entire circumference of the mandrel portion 20.

The tube-making rollers 21 including the driven roller 21a and the driving roller 21b of the mandrel section 20 are arranged in a cylindrical shape having a predetermined spiral angle. When the outer peripheral surface of each pipe-making roller 21 is parallel to the axial center, if each pipe-making roller 21 is arranged in a cylindrical shape so as to have a predetermined spiral angle and each end face position is twisted in the same direction, The outer diameter of the cylinder formed by the end of each pipe-making roller 21,
The outer diameter of the cylinder formed by the central portion of each pipe-making roller 21 is different, the former becomes larger, and the central portion as a whole becomes a constricted drum shape. If a spiral tube is manufactured by winding a strip-shaped body around such a pipe-making roller 21, the strip-shaped body is formed from the pipe-making roller 21.
When the strip 40 is led out, the strip 40 abuts on the end of each pipe-making roller 21, and a large resistance is applied to the strip 40.

In the pipe making machine of the present invention, in order to solve such a problem, each pipe making roller 21 composed of the driven roller 21a and the driving roller 21b has a shape in which the diameter of the central portion is larger than the diameter of each end portion. Has been done. As a result, even if the tube-making rollers 21 are arranged in a cylindrical shape at a predetermined spiral angle, the formed cylinder has a constant outer diameter in the axial direction. If the cylinder to be formed has a constant outer diameter in the axial direction, the strip 40 forcibly wound along all the driven rollers 21a forming the mandrel portion 20 as a spiral tube is the mandrel. It will be carried out smoothly from the part 20. Drive roller of second drive roller pair
21b is arranged coaxially with the driven roller, and both rollers have the same shape as the other tube-making rollers.

The shape of each tube-making roller 21 is determined by the diameter of the spiral tube to be manufactured and the width of the strip. Assuming that the inner diameter of the spiral tube is D and the width of the strip is W, the axis of the tube-making roller 21 is x, as shown in FIG.
The axis and the center of the pipe-making roller 21 and the line orthogonal to the x-axis are y
The axis. The pipe-making roller 21 is symmetrical with respect to the y-axis, and has a maximum diameter on the y-axis and a smaller diameter toward the end. Let Δy be the difference between the diameter (y coordinate) of the pipe making roller and the maximum diameter of the pipe making roller in the x coordinate.
Is expressed by the following equation.

As represented by such an expression, each pipe-making roller 21 has a maximum diameter in the central portion and is gradually reduced in diameter toward each end face, so that each pipe-making roller has a cylindrical shape with a predetermined spiral angle. Even with the above arrangement, the outer diameter of the cylinder formed by each pipe-making roller is constant in the axial direction.

When considering the cross section passing through the axis of each pipe-making roller 21, the shape of the outer peripheral surface thereof is approximated as an arc having a predetermined radius R. As shown in FIG. 6, the outer diameter of the cylinder 30 formed by each tube-making roller 21 (the inner diameter of the spiral tube to be manufactured) is D, the length of the cylinder is B, and the spiral of each tube-making roller 21 is The angle (the angle between the line parallel to the axis of the peripheral surface of the cylinder 30 and the line parallel to the axis of the tube-making roller 21 at the contact portion between the tube-making roller 21 and the cylinder 30) is θ, and The width is W, the twist angle of the tube-making roller 21 (the deviation of the center position on each end surface of the tube-making roller 21 is expressed as the center angle on one end surface of the cylinder 30) is α, and FIG. ), The difference between the maximum diameter (center portion) and the minimum diameter (end surface) of the pipe making roller 21 is Δy.
Then, The following equation is obtained from the equations (2) to (4).

Further, if Δy is eliminated from the equation (5), R is represented by the following equation.

Thus, the outer diameter D of the cylinder formed by each pipe-making roller,
When each pipe-making roller is formed so as to have an arcuate outer peripheral surface having a radius R represented by the length B of the cylinder and the width W of the strip, the cylinder formed by these pipe-making rollers Has a constant outer diameter.

When the length of each pipe making roller is 280 mm and the width of the strip is 95 mm, the inner diameter of the spiral pipe (the outer diameter of the cylinder formed by each pipe making roller) D and the maximum outer diameter of the pipe making roller Table 1 shows the relationship between the maximum value maxΔy of the difference from the minimum outer diameter and the radius R of the arc that defines the outer peripheral surface shape of the pipe making roller.

(Effects of the Invention) In the pipe manufacturing machine of the present invention, the belt-like body is enclosed by the plurality of driven rollers arranged in a cylindrical shape having a predetermined spiral angle in this manner. It is designed to be wound into a spiral and wound in a spiral shape, and tension is applied so that the belt-like body can surely roll contact with each driven roller.
The strip can be easily manufactured into a spiral tube having a predetermined diameter. At the time of pipe making, it suffices to set the rotation speed of each drive roller in advance so that tension is applied to the strip, and there is no need to control the drive rotation speed of each drive roller during pipe making.
Easy to operate. When changing the diameter of the spiral tube to be produced, it is only necessary to replace the mandrel part.

Since the pipe making machine of the present invention is thus regulated in inner diameter, the diameter of the spiral pipe produced even when a large driving force is applied can always be made constant.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an example of the pipe making machine of the present invention,
FIG. 2 is a partially cutaway side view thereof, FIG. 3 is a plan view of an essential part thereof, FIG. 4 is a cross-sectional view of a belt-like body used in the pipe making machine, and FIGS. 5 and 6 (a). , (B) are explanatory views of the shape of the pipe making roller. 10 ... Frame, 15 ... Spindle, 16a ... Drive roller, 16d ... Hydraulic motor,
16e… Gear, 18b… Drive tension roller, 18c… Tension roller for driven, 20… Mandrel part, 21… Pipe-making roller, 2
1a: driven roller, 21b: drive roller, 22, 22a ... roller shaft.

Claims (11)

[Claims] 1. A pipe manufacturing machine for manufacturing a spiral pipe by spirally winding a band-shaped body having engaging portions on both side edges and engaging adjacent engaging portions with each other, each of which is rotatable. And a plurality of driven rollers arranged in a cylindrical shape having a predetermined spiral angle, and provided in parallel with the driven rollers so that the belt-shaped body is sandwiched by two driving rollers and each driven roller is included. And a driving roller pair that rolls and conveys the belt-shaped body to each driven roller, and the belt-shaped body is sandwiched to convey the belt-shaped body to the driven roller, and the speed is lower than the rotation speed of the driving roller pair. A pipe making machine equipped with a pair of tension rollers that rotate at. 2. A driving roller of the driving roller pair,
The pipe according to claim 1, wherein the driven roller and the driven rollers are arranged so as to have a cylindrical shape with a predetermined spiral angle, and the driven roller and the driven rollers form a mandrel portion. Machine. 3. The pipe making machine according to claim 2, wherein the driven roller and the drive roller forming the mandrel portion have a diameter in a central portion in the axial direction larger than a diameter in an end portion. . 4. The drive roller pair is arranged at a position after the belt-shaped body is conveyed from the tension roller and is brought into rolling contact with each driven roller forming a lower half circumference of the mandrel portion. The pipe manufacturing machine according to item 2 of the above. 5. A second drive roller pair capable of sandwiching and transporting a belt-shaped body transported by the drive roller pair is disposed at a position axially symmetrical to a mandrel portion with respect to the drive roller pair. The pipe manufacturing machine according to claim 4. 6. The second drive roller pair applies a tension to the belt-shaped body conveyed from the drive roller pair so that the belt-shaped body is brought into rolling contact with each driven roller constituting the upper half circumference of the mandrel portion. The pipe manufacturing machine according to claim 5. 7. The pipe making machine according to claim 6, wherein one drive roller pair of the second drive roller pair is arranged coaxially with one driven roller forming a mandrel portion. 8. The pipe manufacturing machine according to claim 3, wherein the mandrel portion is detachably disposed on a predetermined frame. 9. A drive roller forming a pair with a drive roller forming a mandrel portion in each drive roller pair is disposed on the frame body so as to be able to come into contact with and separate from each drive roller forming a mandrel portion. The pipe manufacturing machine according to claim 8. 10. The drive roller arranged on the frame body is rotated by a hydraulic motor, respectively.
The pipe manufacturing machine according to item. 11. The pipe manufacturing machine according to claim 10, wherein the drive rollers of each drive roller pair are rotationally driven in opposite directions by a pair of gears that mesh with each other when the drive rollers approach each other.