JPH11227074A - Manufacture of formed paper tube and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the twisting of a tube from the widthwise expansion and contraction of a band stock, ensure its longitudinal strength to pressure and realize the possibility of the use in the form cut in an arbitrary length. SOLUTION: Band stocks 1a-1d are fed axially along a circular sectional circular part 2a formed on the upstream side of a paper feeding direction. After the band-stocks 1a-1d are formed in a circular shape by being urged against the circular part 2a, the circularly shaped band-stocks are fed to a deformed shape part, which is formed at the downstream side of a shaft or is not circular or deformed sectional part such as L-shape in cross-section, so as to urging the stocks against this deformed part in order to form into a deformed shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a molded paper tube, and more particularly, to a method for manufacturing a molded paper tube having an arbitrary length and having no twist. And equipment.

[0002]

2. Description of the Related Art Conventionally, a molded paper tube having a hollow inside has been used for protecting an article, for example, when the article is transported or stored. The molded paper tube is used by applying to the corners and side surfaces of the articles at the time of packaging various articles by utilizing the buffering effect of the paper.

As a method for producing such a molded paper tube, for example, a method called a spiral method is known. For example, in the case of manufacturing a square shaped paper tube by this spiral method, a formed paper tube is formed by winding a strip of paper from an oblique direction while rotating a square shaft serving as a core metal. . However, in this case, the direction of the fiber of the belt-shaped paper is usually the longitudinal direction,
Since it has the property of expanding and contracting in the direction perpendicular to the fiber direction, that is, in the width direction of the belt-shaped paper due to moisture, twisting is caused in a rectangular molded paper tube in which the belt-shaped paper is wound obliquely. Tend. Another drawback is that the pressure resistance of the finished product in the longitudinal direction (longitudinal direction) is not so large.

On the other hand, there is known a method of manufacturing a molded paper tube called a flat winding method. In this method, a strip of paper cut into a predetermined length is wound around a square shaft serving as a core metal so as to be folded in the width direction to form a square shaped paper tube. In this way, it is possible to prevent the fiber from being stretched and twisted in the direction perpendicular to the fiber direction, that is, in the width direction of the band-shaped paper, and the longitudinal direction matches the fiber direction of the band-shaped paper, thereby increasing the pressure resistance. There is. However, since it uses band-shaped paper that has been cut to a predetermined length in advance, it is used as a cushioning material for articles that require a certain length, such as building materials and kitchen sinks, which are protected by hitting them. There was a disadvantage that it could not be done.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to eliminate the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a belt-like paper fed along the axial direction of a shaft. A first shaping portion which is pressed into contact with a circular portion having a circular cross section formed on the upstream side in the paper feeding direction of the shaft and is shaped into a cylindrical shape; and a first shaping portion provided downstream of the first shaping portion, A second forming unit that presses the band-shaped paper formed into a cylindrical shape by the first forming unit with a deformed portion having a non-circular cross-section formed on the downstream side of the shaft and forms the deformed shape. By manufacturing, a molded paper tube is manufactured so as to prevent twisting due to expansion and contraction in the width direction of the band-shaped paper, secure pressure resistance in the vertical direction, and be able to be cut to an arbitrary length for use. That is.

Another object of the present invention is to firstly press the belt-shaped paper into contact with the circular portion to avoid meandering caused by imbalance of the tension of the belt-shaped paper when directly forming into a deformed shape (particularly, asymmetrical cross section). Molded into a good cylindrical shape,
In addition, even if slight meandering occurs due to elongation of the ears, which is a delicate waving that may occur at the widthwise cut end of the band-shaped paper, it is relatively easy to form a circular cross-section, and at the same time, meandering on the circular cross-section The purpose is not to particularly affect the process, and to enhance the applicability for later forming into various irregular shapes.

Still another object is to guide a belt-shaped paper supplied in the axial direction by a cylindrical guide member in advance so as to be rolled along a circular portion, and to press the belt-shaped paper against the circular portion so as to be easily formed into a cylindrical shape. That is.

Another object is to form the deformed portion so that its cross-sectional shape smoothly changes from a circular shape to a non-circular deformed shape, and the second forming portion forms a band-shaped paper formed into a cylindrical shape. By providing a plurality of rollers that are in pressure contact with the deformed portion, the belt-shaped paper is formed while being continuously changed in the axial direction while being gradually changed to a predetermined deformed shape.

Another object of the present invention is to provide a facility in which the second forming section has a press member for moving the band-shaped paper formed into a cylindrical shape in the direction perpendicular to the axis of the shaft and pressing against the deformed section. Is to be simplified.

[0010]

In short, according to the first aspect of the present invention, a plurality of strips of paper are sequentially supplied to a shaft serving as a metal core, stacked, and pressed against the shaft while being fed in the axial direction of the shaft. In the method for manufacturing a formed paper tube to be formed, a belt-shaped paper is supplied in an axial direction along a circular portion having a circular cross section formed on the upstream side in the paper feeding direction of the shaft, and the belt-shaped paper is supplied to the circular portion. After being pressed and formed into a cylindrical shape, the cross section formed on the downstream side of the shaft is sent to a deformed portion having a non-circular deformed shape, and pressed into contact with the deformed portion to be formed into a deformed shape. is there.

According to a second aspect of the present invention, there is provided a method for manufacturing a molded paper tube formed by sequentially supplying a plurality of belt-shaped papers to a shaft serving as a core metal, stacking the belt-shaped papers, and pressing the shafts while pressing the shafts in the axial direction. In the apparatus, a first forming section for pressing a belt-shaped paper supplied along an axial direction of the shaft into a circular section having a circular cross section formed on the upstream side in the paper feeding direction of the shaft to form a cylindrical shape. And a belt-shaped paper provided on the downstream side of the first forming section and formed into a cylindrical shape by the first forming section, wherein the cross-section formed on the downstream side of the shaft has a non-circular irregular shape. And a second molded part that is pressed into contact with the part and molded into an irregular shape.

According to a third aspect of the present invention, in the apparatus for manufacturing a molded paper tube according to the second aspect, the first molding portion has a substantially elliptical entrance and a cross section into which a strip of paper is inserted. And a tubular guide member having an outlet substantially matching the cross-sectional shape of the circular portion of the shaft, and having a cylindrical guide member arranged so that the shaft passes therethrough.

According to a fourth aspect of the present invention, in the apparatus for manufacturing a molded paper tube according to the second aspect, the deformed portion is formed such that its cross-sectional shape smoothly changes from a circular shape to a non-circular shape. The second forming section is formed, and has a plurality of rollers for pressing the strip-shaped paper formed into a cylindrical shape against the deformed section.

According to a fifth aspect of the present invention, in the apparatus for manufacturing a molded paper tube according to the second aspect, the second forming section is configured to cut the band-shaped paper formed into a cylindrical shape in a direction perpendicular to the axis of the shaft. It is characterized in that it has a press device that moves close to and presses against the deformed portion.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1A and 1B are a plan view and a side view, respectively, showing a schematic configuration of a molded paper tube manufacturing apparatus according to an embodiment of the present invention.

The apparatus for manufacturing a molded paper tube shown in FIG. 1 (hereinafter referred to as the present apparatus) sequentially supplies and stacks a plurality of strips of paper 1a to 1d on a shaft 2 serving as a metal core, and the axial direction of the shaft 2. To form a molded paper tube having a hollow with an L-shaped cross section. The apparatus presses the belt-shaped paper supplied along the axial direction of the shaft 2 against a circular section 2a (see FIG. 3 and the like) having a circular cross section formed on the upstream side of the shaft 2 in the paper feeding direction. A first forming part 10 for forming a cylindrical shape by the first forming part 10, and a belt-shaped paper formed into a cylindrical shape by the first forming part 10 on the downstream side of the shaft 2. And a second molding portion 20 formed into an irregular shape by pressing against a modified portion 2b (see FIG. 8 and the like) having an irregular shape whose cross section is not circular.

On the upstream side of the molding sections 10 and 20 of the present apparatus, there are disposed a supply section 30 for supplying the band-shaped paper and an application section 40 for applying the adhesive to the band-shaped paper. A cut portion 50 for cutting the molded paper tube 5 to a predetermined length is arranged.

The supply section 30 is provided on the upstream side of the first molding section 10. The supply unit 30 includes a plurality of base paper rolls 3.
1 and set in a state in which the band-shaped paper is wound. The band-shaped papers 1 a to 1 d have a width substantially corresponding to the length around the shaft 2. The strips 1a and 1c are supplied from below to the shaft 2 while being guided by guide members 11a and 11c described later.
b and 1d are supplied from above to the shaft 2 while being guided by guide members 11b and 11d described later.

FIGS. 2A and 2B are a plan view and a side view, respectively, of the periphery of the coating section 40. Coating rollers 41b to 41d immersed in adhesive tanks 42b to 42d containing the adhesive are in contact with the surfaces of the band-shaped papers 1b to 1d facing the shaft 2. As this adhesive,
Vinyl acetate type is usually used, but urea resin type,
An arbitrary material such as a phenolic resin-based adhesive or glue is used.

On the other hand, since the belt-shaped paper 1a constitutes the innermost layer of the molded paper tube, the adhesive is supplied without being applied. However, paraffin may be applied to the inner side in contact with the shaft 2. This is to improve the slip so that the formed square paper tube is sent in the axial direction and advances.

FIGS. 3A and 3B are a plan view and a side view, respectively, around the guide member 11c of the first molding portion 10.
4 is a sectional view taken along the line IV-IV shown in FIG. 3, FIG. 5 is a sectional view taken along the line VV, and FIG.
It is sectional drawing which follows a line.

In order to form the belt-shaped paper into a cylindrical shape, the first forming unit 10 includes guide members 11a to 11d and back rollers 12a to 1d corresponding to the respective belt-shaped papers 1a to 1d.
2d and side rollers 13a to 13d.
Since these have almost the same functions, only the configuration around the guide member 11c will be described below.

As described above, a circular section 2a having a circular cross section is formed on the upstream side of the shaft 2 in the sheet feeding direction (see FIGS. 1 and 2B). One configuration of one molding unit 10 is provided. Guide member 11
c has a cylindrical shape, and has an inlet 15c having a substantially elliptical cross section into which the band-shaped paper 1c is inserted, and an outlet 16c whose cross section substantially matches the cross sectional shape of the circular portion 2a of the shaft 2. The inside diameter of the entrance 15c of the guide member 11c in the long axis direction is formed to be slightly larger than the widthwise dimension of the band-shaped paper 1c. The guide member 11c is fixedly installed on a support member 14 erected on the upper surface of the base 7 so that the shaft 2 passes therethrough.

Back roller 12c and side roller 13c
Are arranged in this order immediately downstream of the guide member 11c. The rollers 12c and 13c have a drum shape, and the cross-sectional radius of the constricted curved surface at the center is
It is formed so as to substantially coincide with the cross-sectional radius of a. The back roller 12c is provided below the shaft 2 as shown in FIG. 5 so as to abut on the central portion of the web 1c, while the side roller 13c is provided on the side of the shaft 2 as shown in FIG. A pair is provided. The rollers 12c and 13c
Is configured to be pressed against the surface of the circular portion 2a of the shaft 2 with a predetermined force via the belt-shaped paper.

FIG. 7 is a side view showing a drive transmission mechanism for the back roller and the side roller. This drive transmission mechanism
It has a drive shaft 3 connected to rotation drive means such as a motor (not shown), and the rotation of the drive shaft 3 is controlled by a plurality of bevel gears 4a.
The power is transmitted to the rear roller 12b and the side roller 13b via the spur gear 4b and the spur gear 4b. Reference numeral “6” in the figure indicates a bearing mechanism. The drive transmission mechanism does not necessarily have to be as described above, and the drive can be transmitted from the motor shaft using any means such as gears, sprockets, and pulleys.

FIGS. 8A and 8B are a plan view and a side view, respectively, showing a part of the second molded portion in cross section. Note that FIG. 8B is a cross-sectional view of a portion shown below the dashed-dotted line as viewed from the downstream side above the dashed-dotted line.

On the downstream side of the shaft 2, as described above, a deformed portion 2 b having a non-circular cross section is formed. The deformed portion 2 b forms one configuration of the second formed portion 20. ing. As shown in FIG. 8B, the deformed portion 2b
Is an irregular shape whose cross-sectional shape is not circular from circular,
That is, in the present embodiment, it is formed so as to smoothly change to an L-shaped cross section. Also, in this irregularly shaped portion 2b,
It is preferable to provide a heater for the purpose of promoting molding.

In order to form the band-shaped paper having a cylindrical shape into an L-shaped section, the second forming section 20 includes a plurality of rollers 21a to 21a for pressing the band-shaped paper against the deformed portion 2b.
f. The rollers 21a to 21c are
Is disposed below the deformed portion 2b. These rollers 21
Each of a to 21c has a drum shape, but the cross-sectional shape of the constricted curved surface at the center is completed from a shape (the roller 21a) substantially matching the cross-sectional shape of the circular portion 2a to an L-shaped cross section. Shape (the roller 21)
It is formed with variations up to c). On the other hand, the roller 21
d and 21e have a hexagonal cross section along the rotation axis, and are arranged above the irregularly shaped portion 2b. Note that these rollers 21a to 21e are installed such that their rotation axes are perpendicular to the sheet feeding direction in a horizontal plane. Also,
The roller 21f has a drum shape, and the cross-sectional shape of the constricted curved surface at the center is formed to substantially match the outer shape of both ends of the finished product formed into an L-shaped cross section.

The rollers 21a to 21f are configured to be pressed against the surface of the deformed portion 2b of the shaft 2 with a predetermined force via a belt-shaped paper. In addition, it is preferable that knurls for preventing slipping are appropriately formed on the surfaces of the rollers 21a to 21f as needed. Further, rollers 21a to
21f may be heated by a heater (not shown). By doing so, the softening and bonding effects of the formed strip of paper can be enhanced.

FIGS. 9A and 9B are a plan view and a side view of the cut portion, respectively. The cut section 50 is provided at the most downstream in the present apparatus as shown. The molded paper tube 5 having an L-shaped cross section made of a band-shaped paper that is sent in the axial direction while being pressed by the second molded portion 20 is formed by the cut portion 5.
At 0, it is cut by the disc saw 51 to a predetermined length. Disk saw 51 and motor 52 for rotating the disk saw 51
Can be moved by a drive cylinder 53 in a direction perpendicular to the sheet feeding direction of the band-shaped paper, and can be moved by a drive cylinder 54 in a direction along the sheet feeding direction.

Next, a method for manufacturing a molded paper tube having a hollow having an L-shaped cross section will be described while explaining the operation of the present apparatus configured as described above.

The strip-shaped paper 1a constituting the innermost layer supplied from the supply unit 30 is sent to the first molding unit 10 from below without applying an adhesive. Note that the belt-shaped paper 1a is similar to other belt-shaped papers described below, but may be configured by, for example, one containing glass fiber, carbon fiber, or the like. This band-shaped paper 1a
It is inserted into a predetermined gap between the guide member 11a of the first forming part 10 and the circular part 2a of the shaft 2. The strip-shaped paper 1a supplied in the axial direction is guided by a cylindrical guide member 11a, and is previously rounded in the width direction along the circular portion 2a. The rolled strip 1a is rotated by the back roller 12a and the side roller 13a into a circular portion 2a of the shaft 2.
As a result, a cylindrical first layer having a butted portion on the upper side is formed. As described above, since the band-shaped paper is guided by the guide member 11a so as to be rolled in advance, the band-shaped paper can be easily pressed into contact with the circular portion 2a and formed into a cylindrical shape.

Further, the belt-shaped paper 1b is supplied,
The adhesive is applied by b and sent to the first molding unit 10 from above. The strip-shaped paper 1b is inserted into a predetermined gap between the guide member 11b of the first forming part 10 and the circular part 2a of the shaft 2. The band-shaped paper 1b is a cylindrical guide member 1.
1b, and is previously rounded in the width direction along the circular portion 2a. The rolled strip 1b is pressed against the circular portion 2a of the shaft 2 by the back roller 12b and the side roller 13b, so that a cylindrical second layer having a butted portion below is formed. Similarly,
The strip-shaped papers 1c and 1d are supplied, and the cylindrical third and fourth layers are formed. In this way, the belt-shaped paper 1a-1
d is laminated in four layers so that butted portions in the width direction appear alternately up and down, and is formed into a cylindrical shape having uniform strength. As described above, first, the band-shaped paper is pressed against the circular portion 2a, thereby avoiding meandering caused by imbalance of the tension of the band-shaped paper when directly forming into a deformed shape (particularly, an asymmetric cross-sectional shape), thereby achieving a well-balanced cylindrical shape. Molded into
In addition, even if slight meandering occurs due to delicate extension of the strip of paper or the like, it is relatively easy to form a circular cross-section, and meandering on the circular cross-section does not particularly affect the next step. There is. In addition, it is possible to enhance the applicability for later forming into various irregular shapes.

The band-shaped paper thus formed into a cylindrical shape is
It is introduced into the second molding section 20. The belt-shaped paper formed into a cylindrical shape is formed between the plurality of rollers 21a to 21f and the deformed portion 2b of the shaft 2 formed so that the cross-sectional shape smoothly changes from a circular shape to an L-shaped cross-section. Is passed through. The belt-shaped paper is pressed by rollers 21a to 21f rotating on the surface, and is sent forward by being pressed. This is particularly noticeable due to the shallow and narrow grooves, which are knurls carved on the roller surface with knurls. In this way, the strip-shaped paper formed into a cylindrical shape is formed while being continuously fed in the axial direction and gradually changing smoothly into a predetermined L-shaped cross section.

Next, the formed paper tube 5 having an L-shaped cross section sent from the second shaping section 20 is cut into a predetermined length by the cut section 50. Here, the disc saw 51 and the motor 52
Is moved by the drive cylinder 53 in the direction perpendicular to the feed direction of the molded paper tube 5 while being moved downstream by the drive cylinder 54 so as to match the feed speed of the molded paper tube 5. In this way, cutting of a predetermined length is performed while the feeding operation of the molded paper tube 5 is continued.

As described above, according to the present embodiment, since the longitudinal direction of the band paper is the longitudinal direction of the molded paper tube, twisting due to expansion and contraction in the width direction of the band paper is prevented, and the pressure resistance in the vertical direction is secured. Can be cut to any length and used, so it can be used for building materials and kitchen sinks, etc. Can also be used.

FIG. 10 is a view in which cross sections of a plurality of portions of a second molding portion of a molding paper tube manufacturing apparatus according to another embodiment are arranged. The cross section at a plurality of points shown in FIG. 10 is shown in FIG.
Are those corresponding to a plurality of cross sections in FIG.

In this embodiment, the deformed portion 2c is formed such that its cross-sectional shape smoothly changes from a circular shape to a non-circular deformed shape, that is, a square cross-sectional shape, and is formed into a cylindrical shape. A plurality of rollers 2 for pressing the band-shaped paper against the deformed portion 2c in order to form the band-shaped paper into a square cross section.
It is different from the above embodiment in having 1g and 21h. However, the other points are the same as those of the above embodiment, and the description thereof is omitted.

According to this embodiment, it is possible to manufacture a square paper tube as a molded paper tube having an irregular shape, and it is possible to obtain the same effects as those of the above-described embodiment.

Further, as shown in FIG. 11, a deformed portion 2d is formed so that the cross-sectional shape smoothly changes from a circular shape to a U-shaped cross-section, and a plurality of rollers 21i which press the strip-shaped paper against the deformed portion 2d. By providing a length of about 21 s, it is possible to manufacture a molded paper tube having a U-shaped cross section as a modified molded paper tube, and it is possible to obtain the same effects as those described in the above embodiment. It is also possible to manufacture molded paper tubes of various shapes by changing the shape of the deformed portion to a shape other than the above.

FIG. 12 is a side view of a second forming part and a cutting part of a molded paper tube manufacturing apparatus according to still another embodiment, FIG. 13 is a plan view of the same, and FIG.
It is the figure seen from XIV line.

In this embodiment, the second forming section has a press device 25 for moving the band-shaped paper formed into a cylindrical shape close to the shaft 2 at right angles to the deformed portion 2b. This is different from the apparatus for manufacturing a molded paper tube shown in FIG. The press device 25 includes an upper die 26 and a lower die 27. The upper die 26 and the lower die 27 are moved close to each other by a hydraulic press, and a cylindrical strip is sandwiched therebetween to form an L-shaped cross section. You can do it. The upper die 26 and the lower die 27 of the press device 25 are, for example, 2 m along the axial direction of the shaft 2 in accordance with the forming ability.
May be provided by dividing into a plurality.

In this embodiment, a transport section 60 is provided downstream of the cutting section 50. This transport unit 60
Clamp members 61a and 61b for clamping the molded paper tube 5
And drive cylinders 62a and 62b for moving the clamp member 61 forward and backward along the paper feeding direction, and moving these clamp members 61a and 61b and the drive cylinders 62a and 62b on the transport base 63 along the paper feed direction of the band-shaped paper. And a drive cylinder 68 for moving the carriage 63 forward and backward in the direction perpendicular to the sheet feeding direction. The transport device 64 includes a roller chain 65 to which the clamp members 61a and 61b and the drive cylinders 62a and 62b are connected.
And a motor 67 for rotating a pulley 66 around which a roller chain 65 is wound.

The disc saw 51 of the cutting section 50 is configured to be rotationally driven by a motor 52 via a roller chain 53 or the like.
Is movable in the direction perpendicular to the sheet feeding direction along the guide member 54. However, the other points are the same as those of the apparatus shown in FIG. 1, and the description thereof will be omitted.

In this embodiment, the band-shaped paper formed into a cylindrical shape in the first forming portion on the upstream side is pressed by the pressing device 2.
5 is temporarily stopped after being sent between the upper mold 26 and the lower mold 27, and the upper mold 26 and the lower mold 27 are moved close to each other by a hydraulic press. Form into L-shape. When the forming by the press device 25 is completed, the clamp member 61a moves close to the formed paper tube 5 by the drive cylinder 62a and clamps the formed paper tube 5.

Then, the clamp member 61a is moved together with the drive cylinder 62a in the sheet feeding direction to the vicinity of the motor 67 and stopped by the transport device 64. At the same time, the clamp member 61b moves together with the drive cylinder 62b in the direction opposite to the sheet feeding direction to the vicinity of the cut section 50 and stops. Thus, the molded paper tube 5 clamped by the clamp member 61a is conveyed by being pulled out in the downstream direction. After the conveyance of the molded paper tube 5 is stopped, the disk saw 51 of the cutting section 50 is moved to cut the molded paper tube 5 to a predetermined length.

Then, the clamp of the formed paper tube 5 by the clamp member 61a is released, and the transport table 63 is moved by the drive cylinder 68 in the direction perpendicular to the feeding direction of the band-shaped paper. Switching is performed so as to face each other. The molded paper tube 5 having a predetermined length, from which the clamp by the clamp member 61a is released, is carried out by carrying-out means (not shown).

On the other hand, after the clamp member 61b is switched so as to face the molded paper tube 5, the same operation as described above is repeated. In this way, it is possible to continuously manufacture a molded paper tube from a strip of paper, although it is pitch feed.

According to this embodiment, there is no need to provide a drive transmission mechanism such as various gears as in the apparatus shown in FIG.
Equipment can be simplified, and wear of the shaft 2 can be reduced. Moreover, it is possible to obtain the above-described effects similar to those of the apparatus shown in FIG.

The embodiments described above are not described to limit the present invention, and various changes can be made within the technical idea of the present invention. For example, in the above-described embodiment, a molded paper tube is manufactured by stacking four strips of paper, but the number of strips of paper to be stacked can be set as appropriate. Further, a configuration in which a plurality of belt-shaped papers are inserted into the same guide member may be adopted.

[0051]

As described above, according to the first and second aspects of the present invention, the belt-shaped paper is axially moved along the circular portion having a circular cross section formed on the upstream side in the paper feeding direction of the shaft. After the strip-shaped paper is pressed into contact with the circular portion and formed into a cylindrical shape, the cross section formed on the downstream side of the shaft is sent to a deformed portion having a non-circular cross-sectional shape, and pressed against the deformed portion. It is possible to prevent twisting due to expansion and contraction in the width direction of the band-shaped paper, and to secure the pressure resistance in the vertical direction, and cut it to an arbitrary length for use. can do. As a result, there is an effect that it can be used as a cushioning material for an article requiring a certain length, such as a building material or an article such as a kitchen sink.

Further, by pressing the band-shaped paper against the circular portion, it is possible to avoid the meandering caused by the imbalance of the tension of the band-shaped paper in the case where the band-shaped paper is directly formed into a deformed shape, thereby forming a well-balanced cylindrical shape. Even if slight meandering occurs due to delicate extension of the paper or the like, it is relatively easy to form a circular section, and meandering on the circular section does not particularly affect the next step. Further, the applicability for later forming into various irregular shapes can be enhanced.

According to the third aspect of the present invention, it is possible to guide the band-shaped paper supplied in the axial direction so as to be rolled in advance along the circular portion by the cylindrical guide member, and press the rolled paper against the circular portion. Thus, there is an effect that it becomes easy to form a cylindrical shape.

According to the fourth aspect of the present invention, the deformed portion is formed so that its cross-sectional shape smoothly changes from a circular shape to a non-circular deformed shape, and the belt-shaped paper formed into a cylindrical shape is deformed. Since a plurality of rollers are provided so as to be in pressure contact with the portion, the belt-shaped paper can be formed while being continuously fed in the axial direction while being gradually changed to a predetermined irregular shape.

According to the fifth aspect of the present invention, since the press device is provided, there is no need to provide a drive transmission mechanism such as various gears, so that the equipment can be simplified and the shaft can be improved. Can be reduced.

[Brief description of the drawings]

FIGS. 1A and 1B are a plan view and a side view, respectively, showing a schematic configuration of an apparatus for manufacturing a molded paper tube according to an embodiment of the present invention.

FIGS. 2A and 2B are a plan view and a side view, respectively, of the periphery of a coating section.

FIGS. 3A and 3B are a plan view and a side view, respectively, around a guide member of a first molded portion.

FIG. 4 is a sectional view taken along the line IV-IV shown in FIG.

FIG. 5 is a sectional view taken along the line VV.

FIG. 6 is a sectional view taken along the line VI-VI.

FIG. 7 is a side view showing a drive transmission mechanism of a back roller and a side roller.

FIGS. 8A and 8B are a plan view and a side view showing a part of the second molded portion in cross section, respectively.

FIGS. 9A and 9B are a plan view and a side view of a cut portion, respectively.

FIG. 10 is a diagram in which a plurality of cross sections of a second forming portion of a manufacturing apparatus for a formed paper tube according to another embodiment are arranged.

FIG. 11 is a view in which a plurality of cross sections of a second forming section of a manufacturing apparatus for a formed paper tube according to still another embodiment are arranged.

FIG. 12 is a side view of a second forming unit and a cutting unit of a device for manufacturing a formed paper tube according to still another embodiment.

FIG. 13 is a plan view of the same.

FIG. 14 is a view taken along line XIV-XIV of FIG.

[Explanation of symbols]

 1a to 1d: band-shaped paper, 2: shaft, 2a: circular portion, 2b to 2d: deformed portion, 10: first molded portion, 11a to 11d: guide member, 15a to 15d: inlet, 16a to 16d: outlet, Reference numeral 20: second forming portion, 21a to 21s: roller, 25: press device.

Claims (5)

[Claims] 1. A plurality of strips (1a to 1d) are sequentially supplied to and laminated on a shaft (2) serving as a cored bar.
In the method for manufacturing a molded paper tube formed by being pressed and pressed while being sent in the axial direction of the shaft, the belt-shaped paper (a) is formed along a circular portion (2a) having a circular cross section formed on the upstream side in the paper feeding direction of the shaft (2). 1a to 1d) are supplied in the axial direction, and the belt-shaped paper (1a to 1d) is pressed into contact with the circular portion (2a) to form a cylindrical shape, and then the shaft (2)
The cross section formed on the downstream side of the non-circular shape is sent to a deformed portion (2b to 2d) having a non-circular shape, and is pressed into contact with the deformed portion (2b to 2d) to be formed into a deformed shape. Production method. 2. A molded paper formed by sequentially supplying and laminating a plurality of strips of paper (1a to 1d) to a shaft (2) serving as a metal core, and pressing and pressing the shaft in the axial direction of the shaft (2). In the pipe manufacturing apparatus, the strip-shaped paper (1) supplied along the axial direction of the shaft (2) may be used.
a to 1d) are pressed into contact with a circular section (2a) having a circular cross section formed on the upstream side in the sheet feeding direction of the shaft (2) to form a cylindrical section, and a first forming section (10); The strip-shaped paper (1a to 1d) provided downstream of the first forming section (10) and formed into a cylindrical shape by the first forming section (10).
) Is formed on the downstream side of the shaft (2) by pressing against a deformed portion (2b-2d) having a non-circular cross-section and formed into a deformed shape. An apparatus for manufacturing a molded paper tube. 3. The first molded part (10) is formed of a band-shaped paper (1a to 1).
1d) is provided with an inlet (15a to 15d) having a substantially elliptical cross section into which the inserted part is inserted, and an outlet (16a to 16d) whose cross section substantially matches the cross sectional shape of the circular portion (2a) of the shaft (2). A cylindrical guide member (11a to 11a) in which the shaft (2) is disposed so as to pass therethrough.
The apparatus for manufacturing a molded paper tube according to claim 2, characterized by comprising 11d). 4. The deformed portion (2b to 2d) is formed such that its cross-sectional shape smoothly changes from a circular shape to a non-circular deformed shape, and the second molded portion (20) has a cylindrical shape. The apparatus according to claim 2, further comprising a plurality of rollers (21a to 21s) for pressing the band-shaped paper (1a to 1d) formed into a shape to the deformed portions (2b to 2d). 5. The second forming section (20) moves the strip-shaped paper (1a to 1d) formed into a cylindrical shape in the direction perpendicular to the axis of the shaft (2) to move the deformed sections (2b to 2d). 3. The apparatus for manufacturing a molded paper tube according to claim 2, further comprising a press device (25) for pressing against said 2d).