JP6346101B2 - Winding core manufacturing method - Google Patents

Description

The present invention relates to a winding core manufacturing how, in particular for example, a long film is wound into a roll, about the winding core manufacturing how.

  Generally, the film is shipped in a state where it is wound around a cylindrical core. Here, when a film is wound around a winding core having a circular cross section, a step occurs at the winding start end portion of the film, and thus a step mark (deformation) due to this step may occur in the film. Therefore, in order to prevent the occurrence of such step marks, a technique is known in which a step portion having the same depth (step height) as the thickness of the film is formed in advance on the outer peripheral surface of the winding core. Yes. In addition, when fixing the winding start edge part of a film to a winding core using adhesive members, such as an adhesive tape, the level | step-difference part which has the depth which added the thickness of the adhesive member to the thickness of the film is formed.

  Patent Document 1 discloses an example of a method for manufacturing a winding core having a stepped portion on the outer peripheral surface. In the manufacturing method of Patent Document 1, after forming a raw tube (core material) having a cross-sectional shape that matches a desired cross-sectional shape of a core by extrusion-molding a thermoplastic resin, the original tube has a predetermined length. By cutting to the right, a core having a step portion extending along the axial direction of the core and having a depth substantially equal to the thickness of the film (sheet-shaped roll) is manufactured.

JP 2007-119230 A

  However, as in the technique of Patent Document 1, when the core is manufactured by profile extrusion molding, the size of the core, such as the diameter and thickness of the core, and the thickness of the film to be wound (that is, the depth of the stepped portion to be formed) ), It is necessary to prepare a deformed die and a deformed sizing forma (cooling cap). For this reason, the technique of Patent Document 1 is difficult to adopt due to the large equipment cost. Further, in the profile extrusion molding, there is a problem that the shape of the stepped portion is not clear and it is difficult to accurately form the stepped portion having a small depth.

Another object of the present invention is to provide a novel, core manufacturing how.

Another object of the present invention can reduce the cost, and the desired stepped portions can be accurately formed, it is to provide a manufacturing how the core.

1st invention is the manufacturing method of the core by which a film is wound around an outer peripheral surface, Comprising: The extrusion molding process which manufactures a cylindrical original tube by extruding a thermoplastic resin using an extrusion molding apparatus, A cutting step of forming a step portion extending along the axial direction with respect to the outer peripheral surface of the original pipe using a cutting machine, and the pressing force acts on the cutting machine in the direction of forming the step portion. A presser roller for pressing the original pipe so that the cutting machine is arranged on the line of the extrusion process of the original pipe, and the arrangement position is on the upstream side of the take-up machine provided in the extrusion apparatus, and the cutting process Is a method for manufacturing a core, which is performed continuously with the extrusion process.

According to the first invention, it is possible to reduce the cost, can be more accurately form a desired stepped portion. Further, since the cutting process for forming the stepped portion in the original pipe is continuously performed in-line with the extrusion process, the winding core can be efficiently manufactured, and the manufacturing cost can be reduced. In addition, since the cutting machine is arranged upstream of the take-up machine in the direction of extruding the original pipe, it is possible to prevent the operating vibration of the cutting machine from being transmitted to the original pipe passing through the cutting machine. For this reason, the displacement of the original pipe at the time of cutting can be suppressed appropriately, and the step portion can be formed more accurately.

2nd invention is a manufacturing method of the core by which a film is wound around an outer peripheral surface, Comprising: The extrusion process which manufactures a cylindrical original pipe by extruding a thermoplastic resin using an extrusion molding device, A cutting step of forming a step portion extending along the axial direction with respect to the outer peripheral surface of the original pipe using a cutting machine, and the pressing force acts on the cutting machine in the direction of forming the step portion. The cutting machine is provided with an end mill arranged so that its axis extends along the tangential direction of the outer peripheral surface of the original tube, and the outer peripheral surface of the end mill faces the tip side. This is a method for manufacturing a winding core having a tapered portion with a small diameter.

According to the second invention, it is possible to reduce the cost, can be more accurately form a desired stepped portion. Moreover, in 2nd invention, a cutting machine is equipped with the end mill for cutting an original pipe and forming a level | step-difference part. This end mill is arranged such that its axis extends in the tangential direction of the outer peripheral surface of the original pipe. Accordingly, step portions having various shapes can be formed by appropriately changing the outer peripheral surface shape of the end mill. Further, a taper portion having a diameter that decreases in a curved or straight line toward the tip end is formed on the outer peripheral surface of the end mill. When the end mill is not formed with a tapered portion, a bent portion is formed at the side edge of the step portion opposite to the side surface (rising surface) on the winding core. The bent portion formed at the side edge of the step portion is basically no problem, but may cause a step mark depending on the material of the film. Therefore, by forming a tapered portion in the end mill and making the bent portion curved or wide-angled, it is possible to more appropriately prevent a step mark from being generated on the film.

A third invention is dependent on the second invention, and a tip end portion of the end mill has a protrusion formed in a bowl shape, and a guide groove for guiding the cutter in the cutting process is provided with a stepped portion by the end mill. Formed simultaneously.

In the third invention, a hook-shaped protrusion is formed at the tip of the end mill. When the step is formed by cutting the original tube, at the same time, a guide groove for guiding the cutter is formed by the projection of the end mill.

According to the third invention, the step portion and the guide groove can be formed at the same time by one end mill, that is, a single cutting process, so that the cutting process can be simplified or made efficient.

  According to this invention, since the stepped portion is formed by cutting, it is possible to manufacture a core having various sizes and depths of the stepped portion, as compared with the case where the core is manufactured by profile extrusion molding. Cost can be reduced. In addition, by providing the cutting machine with a pressing roller that presses the original pipe so that the pressing force acts in the direction in which the stepped portion is formed, the displacement of the original pipe in the depth direction of the stepped portion is appropriately suppressed, A desired stepped portion is accurately formed by cutting.

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

It is an illustration figure which shows the external appearance of the winding core which is one Example of this invention. It is an illustration figure which expands and shows the A part of the winding core of FIG. It is a table | surface which shows the experimental result about the relationship between the ratio W and protrusion ratio V in a winding core, and a level | step difference trace reduction effect. It is an illustration figure which shows roughly an example of the manufacturing apparatus which manufactures the winding core of FIG. It is a side view which shows an example of the cutting machine with which the manufacturing apparatus of FIG. 1 is provided, Comprising: The mode which looked at the cutting machine from the downstream of the extrusion direction of an original pipe is shown. It is a front view of the cutting machine of FIG. 5, Comprising: The mode which looked at the cutting machine from the direction orthogonal to the extrusion direction of an original pipe is shown. It is an illustration figure which shows a mode that an original pipe is cut with an example of the end mill with which the cutting machine of FIG. 5 is provided. It is an illustration figure which shows the contact position with respect to the original pipe of the press roller with which the cutting machine of FIG. 5 is provided. It is an illustration figure which shows a mode that an original pipe is further cut by a 2nd end mill. It is an illustration figure which shows another example of an end mill. It is an illustration figure which shows another example of an end mill. It is an illustration figure which shows another example of an end mill. It is an illustration figure which shows another example of an end mill. It is a front view which shows another example of a cutting machine.

  With reference to FIG. 1 and FIG. 2, the winding core 10 which is one Example of this invention is used in order to wind up the elongate film 100 in roll shape.

  The film 100 wound around the winding core 10 is various films such as a touch panel film, a semiconductor film, and an optical film, and the thickness thereof is, for example, 100 to 500 μm. The film 100 may have a single layer structure, or may have a multilayer structure in which, for example, an adhesive layer or a conductive layer is laminated on a film base material. Note that the film 100 may be referred to as a sheet or a film depending on the thickness, material, and the like.

  As shown in FIGS. 1 and 2, the winding core 10 is formed in a substantially cylindrical shape having a stepped portion 12 on its outer peripheral surface by a thermoplastic resin or the like. The inner diameter of the winding core 10 is, for example, 50-300 mm, and the axial length thereof is, for example, 100-2000 mm.

  The material of the winding core 10 is ABS (acrylonitrile butadiene styrene) resin, polyvinyl chloride, polypropylene, polyethylene, polystyrene, AS (acrylonitrile styrene) resin, polycarbonate, polyethylene terephthalate, polyamide, polyphenylene sulfide, polylactic acid, PGA ( Polyglycolic acid) and thermoplastic resins such as plant-derived resins, or alloys of these thermoplastic resins. Among these, ABS resin or polyvinyl chloride is preferably used.

  Moreover, the thermoplastic resin used as the raw material of the winding core 10 may contain fillers such as talc, calcium carbonate, clay, mica, silica, glass fiber, and carbon fiber. By adding a filler to the thermoplastic resin, an effect of improving strength, an effect of reducing bending and an effect of improving dimensional accuracy by reducing the linear expansion coefficient can be obtained. Among these, talc-containing ABS resin or talc-containing polypropylene is preferably used. At this time, the amount of talc added is preferably 3 to 15%. This is because if the amount of talc added exceeds 15%, the core 10 is easily cracked. If the amount of talc added is less than 3%, the strength improving effect, the bending reducing effect, and the dimensional accuracy improving effect are small. Because it becomes. An alloy of talc-containing polylactic acid and an ABS resin is also preferably used. Further, a carbon fiber-containing thermoplastic resin using polypropylene, ABS resin, polyamide resin, polyethylene terephthalate or polyphenylene sulfide as the thermoplastic resin of the substrate is also preferably used.

  The step portion 12 formed on the outer peripheral surface of the winding core 10 is formed to eliminate a step mark caused by the winding start end portion of the film 100, and extends along the axial direction of the winding core 10. In addition, it is formed over the entire length in the axial direction. The step portion 12 includes a side surface 12a that rises in the thickness direction (radial direction) of the core 10 and a bottom surface 12b that is formed in a direction (tangential direction) orthogonal to the side surface 12a.

  Further, an adhesive member 14 for fixing the winding start end portion of the film 100 to the winding core 10 is provided on the bottom surface 12 b of the step portion 12. When the film 100 is wound around the winding core 10, the film 100 is wound around the bottom surface 12 b of the step portion 12 so that the front end of the film 100 is in contact with or close to the side surface 12 a of the step portion 12. The starting end is fixed via the adhesive member 14.

  As the adhesive member 14, an adhesive tape having adhesiveness on both sides (double-sided tape), an adhesive tape without a substrate, an adhesive, and the like are used. The thickness of the adhesive member 14 is, for example, 10-50 μm. However, the adhesive member 14 is not necessarily provided. For example, when the adhesiveness of the film 100 itself is large, the winding start end portion of the film 100 is directly attached to the bottom surface 12b of the stepped portion 12. It may be fixed.

  Further, the depth X of the stepped portion 12 (step height), that is, the length of the side surface 12a in the thickness direction of the core 10 is a thickness obtained by combining the thickness of the film 100 and the thickness of the adhesive member 14 (hereinafter referred to as “film”). It is referred to as a “thickness of 100, etc.”). That is, when the winding start end of the film 100 is fixed to the core 10, the depth X of the step portion 12 is set so that the winding start end of the film 100 slightly protrudes from the step portion 12. Is done.

  This is because the film 100 and the adhesive member 14 are softer than the core 10 and are compressed by the winding pressure, so that the depth X of the stepped portion 12 is set in advance to the same thickness as the thickness Y of the film 100 or the like. This is because, when the film 100 is wound, the upper end of the side surface 12a of the step portion 12 protrudes from the winding start end portion of the film 100, which may cause a step mark on the film 100. .

  Therefore, in this embodiment, the depth X of the step portion 12 is set smaller than the thickness Y of the film 100 or the like. The ratio W (W = X / Y) of the depth X of the stepped portion 12 to the thickness Y of the film 100 or the like is preferably 0.56 to 0.86. That is, the protrusion ratio V (V = (Y−X) / X) indicating the ratio of the upper surface portion of the film 100 protruding from the stepped portion 12 is preferably 0.14 to 0.80. When the protrusion ratio V of the film 100 is smaller than 0.14, there is a high possibility that a step mark due to the step portion 12 is generated in the film 100. When the protrusion ratio V is larger than 0.80, the winding of the film is increased. There is a high possibility that step marks resulting from the start end portion are generated in the film 100.

  When the adhesive member 14 is not provided on the winding core 10, the thickness Y of the film 100 or the like means the thickness of the film 100 itself.

  In FIG. 3, the experimental result about the relationship between the ratio W, the protrusion ratio V, and the level | step difference trace reduction effect by inventors etc. is shown. In this experiment, three types of experimental bodies (winding cores) were prepared by changing the depth X of the stepped portion, and the stepped trace reduction evaluation was performed. In the evaluation of the step mark reduction, it was determined that the step mark did not occur or the step mark was reduced to such an extent that it could be adopted as a product. On the other hand, the case where the step mark was not reduced or the step mark was reduced only to the extent that it could not be adopted as a product was determined as NG.

  As shown in the table of FIG. 3, a good step scar reduction effect was recognized for the winding core having a protrusion ratio V of 0.14-0.80 (ratio W of 0.56-0.86). On the other hand, an effective step mark reduction effect was not recognized for a core having a protrusion ratio V of less than 0.14 and a core having a protrusion ratio of greater than 0.80.

  Moreover, although illustration is abbreviate | omitted, when the outer peripheral surface of the winding core 10 is provided with the mark for showing the position of the level | step-difference part 12 (namely, winding start position of the film 100) using an inkjet printing machine etc. Good. As a mark, a graphic such as a straight line or a dotted line extending along the axial direction of the winding core 10 or an arrow pointing to the side surface 12a may be displayed on the bottom surface 12b or the top surface of the side surface 12a of the stepped portion 12. Since the depth of the stepped portion 12 is small and the stepped portion 12 itself is not conspicuous, the work of winding the film 100 around the core 10 is facilitated by clearly indicating the position of the stepped portion 12 using a mark.

  FIG. 4 is an illustrative view schematically showing an example of a manufacturing apparatus 30 for manufacturing the winding core 10. Hereinafter, an example of a method for manufacturing the core 10 using the manufacturing apparatus 30 will be described with reference to FIG. 4. In the manufacturing method of the core 10, basically, an extrusion process for extruding the cylindrical original tube 102 using an extrusion molding apparatus, and a step on the outer peripheral surface of the original tube 102 using a cutting machine 50 are used. And a cutting process for forming the part. And in the manufacturing method (manufacturing apparatus 30) of this Example, the cutting machine 50 is incorporated on the line of an extrusion molding process (extrusion molding apparatus), and the cutting process using the cutting machine 50 is an extrusion molding process. Performed continuously inline (online). That is, the manufacturing apparatus 30 includes an extrusion molding apparatus and a cutting machine 50.

  Specifically, the extrusion molding apparatus is an apparatus for manufacturing a cylindrical original pipe 102, that is, a circular original pipe 102 having no stepped portion by extruding a thermoplastic resin. In order from the upstream side in the extrusion direction, an extruder 32, a die 34, a vacuum sizing 36, a spray cooling bath 38, a caterpillar (block type) take-up machine 40, a cutting machine 42, and the like are included. As the extrusion molding apparatus, a general apparatus for a cylindrical tube (for example, a winding core having no step portion) may be appropriately used.

  In this embodiment, the cutting machine 50 is incorporated on the line of the extrusion process using the extrusion apparatus as described above. Specifically, the cutting machine 50 is disposed on the upstream side of the take-up machine 40 in the extrusion direction of the original tube 102, that is, between the spray cooling bath 38 and the take-up machine 40. A specific configuration of the cutting machine 50 will be described later.

  In such a manufacturing apparatus 30, the molten thermoplastic resin is sent from the extruder 32 to the die 34. The thermoplastic resin passes through the die 34 and is continuously extruded into the cylindrical original tube 102. The original tube 102 pushed out of the die 34 is cooled by passing through the vacuum sizing 36 and sized into a cylindrical shape having a predetermined size. The original tube 102 sized by the vacuum sizing 36 is further cooled in a spray cooling bath 38. The cooled cylindrical original tube 102 passes through the cutting machine 50, and after the stepped portion extending along the axial direction is cut on the outer peripheral surface thereof, it is taken up by the take-up machine 40, and the cutting machine 42. And in the cutting machine 42, the core 10 is manufactured by cut | disconnecting to predetermined length.

  In addition, about the structure of the manufacturing apparatus 30, it can change suitably. For example, the spray cooling bath 38 is not necessarily provided. Further, in order to suppress the displacement (meandering or vibration) of the original tube 102 during the cutting process, a belt-type take-up machine can be used instead of the caterpillar-type take-up machine 40. Further, the cutting machine 50 can be arranged on the upstream side of the cutting machine 42, that is, between the take-up machine 40 and the cutting machine 42. However, in this case, since the operating vibration of the cutting machine 42 may be transmitted to the original pipe 102 passing through the cutting machine 50, from the viewpoint of suppressing the displacement of the original pipe 102 during the cutting process, the cutting process is performed. The machine 50 is preferably arranged upstream of the take-up machine 40.

  Next, the configuration of the cutting machine 50 will be specifically described with reference to FIGS. 5 and 6. The cutting machine 50 includes a support base 52 that is a rectangular parallelepiped frame. Wheels 54 are provided at the four corners of the lower end portion of the support base 52, and a fixing portion 56 having a height adjusting mechanism is provided. That is, the support base 52 (and thus the cutting machine 50) can be moved by the wheels 54, and is fixed at a predetermined position by the fixing portion 56 so that the height of the upper surface can be adjusted.

  Further, an apparatus main body of the cutting machine 50 including an end mill 58, a support roller 60, a presser roller 62, a right and left fixing roller 64, and the like is provided on the upper surface of the support base 52. As will be described later, the end mill 58 and the pressing roller 62 are integrated as an upper unit 70, and the upper unit 70 is provided above the support base 52 so that the arrangement height can be adjusted (can be raised and lowered). 5 and 6 show a state in which the upper unit 70 including the end mill 58 and the pressing roller 62 is in the raised position.

  The end mill 58 is a rod-shaped cutting member for cutting the upper part (top) of the outer peripheral surface of the original tube 102 described above, and is connected to the drive shaft of the motor 66 via a connecting member such as a shaft coupling. The end mill 58 rotates around its axis by receiving a driving force from the motor 66 and cuts the original tube 102 with a blade formed on the outer peripheral surface thereof. The diameter of the end mill 58 is, for example, 10 mm, and the axial length thereof is, for example, 150 mm.

  Further, the end mill 58 is disposed sideways in this embodiment. That is, the end mill 58 is disposed such that its axis extends along the tangential direction of the outer peripheral surface of the original tube 102. As can be clearly understood from FIG. 7, a side surface 12 a of the stepped portion 12 is formed along the distal end surface of the end mill 58 on the outer peripheral surface of the original tube 102 (winding core 10) that passes through the cutting machine 50. A bottom surface 12b of the stepped portion 12 is formed along the outer peripheral surface. If the end mill 58 is disposed sideways as described above, the stepped portion 12 having various shapes can be processed by appropriately changing the outer peripheral surface shape of the end mill 58 as in another example of the end mill 58 described later. .

  However, FIG. 7 schematically shows a state in which the original tube 102 is cut by the end mill 58, and the corresponding relationship between the depth and width of the stepped portion 12, and the diameter and axial length of the end mill 58. Is not an accurate indication.

  Although not shown, the connecting member that connects the end mill 58 and the drive shaft of the motor 66 may be provided with one or more fixing members (support structures) that support the connecting member. In order to appropriately prevent the end mill 58 from shaking, the fixing member is preferably provided in the vicinity of the end mill 58, and the axial length of the end mill 58 itself is preferably set small. By providing the fixing member with respect to the connecting member, the end mill 58 is prevented from swinging, so that the processing accuracy of the stepped portion 12 by the end mill 58 is improved.

  Returning to FIG. 5 and FIG. 6, the support roller 60 and the pressing roller 62 are provided on the upstream side and the downstream side of the end mill 58 in the extrusion direction of the original tube 102. The support roller 60 and the presser roller 62 constitute a vertical fixing roller that cooperates with each other to restrict vertical displacement (meandering or vibration) of the original tube 102. That is, the support roller 60 supports the original tube 102 from below, and the presser roller 62 presses the original tube 102 from above, that is, from the direction in which the step portion 12 is formed. Specifically, the support roller 60 and the presser roller 62 are V-groove driven rollers, and the original tube 102 is sandwiched at a predetermined pressure therebetween, thereby preventing the vertical displacement of the original tube 102. It rotates around its axis as the original tube 102 moves in the extrusion direction. The distance between the shaft of the end mill 58 and the shaft of the pressing roller 62 disposed on the upstream side and the downstream side thereof is, for example, 130 mm.

  Also, rubber lining is preferably applied to the surfaces of the V grooves of the support roller 60 and the presser roller 62. As a result, the grip force of the support roller 60 and the pressing roller 62 against the original pipe 102 is improved, and the vertical displacement of the original pipe 102 can be more effectively prevented.

  Such a support roller 60 is provided so as not to move with respect to the upper surface of the support base 52. When the cutting machine 50 is arranged on the line of the extrusion process of the original pipe 102, the height of the fixing portion 56 is set so that the outer peripheral surface of the original pipe 102 contacts the surface of the V groove of the support roller 60. The arrangement height of the support roller 60 is adjusted using the height adjusting mechanism.

  Further, the presser roller 62 is integrated with the end mill 58 and the motor 66 by the support frame 68 or the like to constitute the upper unit 70. The entire upper unit 70 can be adjusted in height along the support shaft 74 by the elevating cylinder 72. Further, in the upper unit 70, the end mill 58 and the motor 66 can adjust the relative position in the vertical direction with respect to the presser roller 62 in accordance with the operation of the handle 78. When manufacturing the winding core 10 using the manufacturing apparatus 30, the entire upper unit 70 moves downward so that the presser roller 62 can sandwich the original tube 102 with the support roller 60 with a predetermined pressure. To be fixed. Further, the arrangement height of the end mill 58 is finely adjusted so that the stepped portion 12 having a desired depth can be formed. That is, the end mill 58 can form the step portions 12 having various depths by changing the relative position with respect to the presser roller 62.

  The left and right fixing rollers 64 are provided on the upstream side of the upstream support roller 60 and on the downstream side of the downstream support roller 60, respectively. The right and left fixing rollers 64 are a pair of flat type driven rollers (right pressing roller and left pressing roller), and can be moved in the lateral direction so that the distance between them can be adjusted according to the operation of the handle 78. Is done. The right and left fixing roller 64 regulates the displacement (meandering or vibration) in the lateral direction of the original tube 102 by sandwiching the original tube 102 with a predetermined pressure from both sides. Rotate around that axis.

  Further, although not shown in the drawings, the cutting machine 50 is provided with a scrap removing unit for removing the cutting scrap generated by the cutting from the original tube 102. As the scrap removing unit, for example, a blower that is provided in the vicinity of the end mill 58 and blows air against the cutting portion of the original tube 102 is used. However, the dust removal unit may be a dust collector that is disposed at a position facing the end mill 58 with the original tube 102 interposed therebetween, and sucks the cutting waste.

  And in the manufacturing method (cutting machine 50) of this Example, as shown in FIG. 8, the contact position with respect to the original tube 102 of the pressing roller 62 arrange | positioned downstream of the end mill 58 is the level | step-difference part 12, That is, the position is shifted from the cutting portion by a predetermined angle. That is, the angle is set such that the displacement of the original tube 102 can be appropriately suppressed while preventing the pressing roller 62 from contacting the stepped portion 12 (cutting portion).

  Here, in order to improve the processing accuracy of the depth of the stepped portion 12, it is necessary to make the displacement of the original pipe 102 in the depth direction (vertical direction) of the stepped portion 12 as small as possible. Therefore, it is important to hold down the original tube 102 from above by the pressing roller 62 so that a pressing force acts on the direction in which the stepped portion 12 is formed. On the other hand, when the pressing roller 62 contacts the stepped portion 12, particularly the upper end of the side surface 12a, the stepped portion 12 is deformed, and the stepped portion 12 having a desired shape or depth may not be formed. That is, there is a possibility that the processing of the stepped portion 12 may be affected. Further, when the presser roller 62 comes into contact with the stepped portion 12, the balance with which the presser roller 62 presses the original tube 102 is deteriorated, and the displacement of the original tube 102 may not be appropriately suppressed.

  Therefore, in this embodiment, the contact position of the presser roller 62 with respect to the original tube 102 is set to a position shifted from the step portion 12 by a predetermined angle. In order to prevent the presser roller 62 from coming into contact with the stepped portion 12 and appropriately suppress the displacement of the original tube 102, the contact position between the presser roller 62 and the original tube 102 from the side surface 12 a of the stepped portion 12. The angle α up to (contact center) is preferably set to 22.5-45 degrees. In this embodiment, the angle α is set to 30 degrees.

  As described above, according to the method for manufacturing the core 10 of this embodiment, the step portion 12 is formed by cutting, and therefore the core 10 having various sizes (diameter and thickness) and the depth of the step portion 12 is formed. Compared with the case where the core is manufactured by profile extrusion molding, the equipment cost can be reduced. Further, the cutting machine 50 includes a pressing roller 62 that presses the original tube 102 so that a pressing force acts in the direction in which the stepped portion 12 is formed, so that the displacement of the original tube 102 in the depth direction of the stepped portion 12 is achieved. Is appropriately suppressed, and the desired stepped portion 12 is accurately formed by cutting.

  Further, according to this embodiment, the contact position of the presser roller 62 with respect to the original tube 102 is shifted from the stepped portion 12 by a predetermined angle, so that the original tube is not affected without affecting the processing of the stepped portion 12. The displacement of 102 can be suppressed appropriately. Therefore, the desired stepped portion 12 can be accurately formed.

  Furthermore, according to this embodiment, since the depth X of the stepped portion 12 is set smaller than the thickness Y of the film 100 or the like, it is possible to suppress the occurrence of a step mark caused by the stepped portion 12, and the thickness Y of the film or the like Compared with the case where the step portion 12 having the same depth X is formed, step marks generated on the film 100 can be more appropriately prevented or reduced. Moreover, by setting the depth of the stepped portion 12 to be small, it is possible to reduce the amount of cutting in the cutting process, and it is possible to reduce the amount of generated cutting waste. Furthermore, since the generation amount of cutting waste is small, it becomes easy to remove the cutting waste by a waste removal unit such as a blower.

  Furthermore, according to this embodiment, since the cutting process for forming the step portion 12 is continuously performed in-line with the extrusion molding process, the winding core 10 can be efficiently manufactured, and the manufacturing cost is reduced. Can be achieved. Further, by disposing the cutting machine 50 upstream of the take-up machine 40 in the extrusion direction of the original pipe 102, it is possible to prevent the operating vibration of the cutting machine 42 from being transmitted to the original pipe 102 passing through the cutting machine 50. For this reason, the displacement of the original pipe 102 at the time of cutting can be suppressed appropriately, and the step part 12 can be formed more accurately.

  Here, in the case where the cutting process for forming the stepped portion 12 is performed as an outline separately from the extrusion molding process, the thickness difference in the circumferential direction of the original pipe 102 in the process of cooling the original pipe 102 to room temperature after the extrusion molding. Due to the above, there is a case where the original pipe 102 is bent in the axial direction. If the original tube 102 is bent, it takes time to position the original tube 102 with respect to a conventional cutting machine such as a milling machine. Further, since it is necessary to manually install the short original pipes 102 one by one in the cutting machine, it takes extra time. On the other hand, as in this embodiment, the cutting process is continuously performed in-line with the extrusion molding process, so that the original tube 102 and the end mill are used by using the support roller 60, the pressing roller 62, the right and left fixing rollers 64, and the like. The stepped portion 12 can be accurately cut over the entire length of the original tube 102 only by the initial position setting in which the positional relationship with 58 is constant.

  Further, once the original pipe 102 is bent, it is difficult to correct the bend and make the original pipe 102 straight, so that the depth and width of the stepped portion 12 can be reduced during cutting with a cutting machine. Variation will occur. In particular, when manufacturing the core 10 having an axial length of 1 m or more, the variation becomes large. On the other hand, as in this embodiment, the cutting process is continuously performed in-line with the extrusion molding process, so that cutting is performed in a state where the bending of the original pipe 102 immediately after the extrusion molding is small or in a state where the bending is small. The processing can be completed. Therefore, it is not necessary to correct the bending of the original pipe 102, and the step portion 12 can be accurately formed over the entire length of the original pipe 102.

  In this way, the cutting process can be continuously performed in-line with the extrusion process by the inventors developing a cutting machine 50 having the configuration shown in FIGS. 5 and 6. Is.

  In the above-described embodiment, one end mill 58 is provided in the cutting machine 50. However, the cutting machine 50 may include two or more end mills. For example, when the stepped portion 12 is cut using the rod-shaped end mill 58 as in the above-described embodiment, a bent portion is formed on the side edge 12c (see FIG. 7) opposite to the side surface 12a of the stepped portion 12. . The bent portion of the side edge 12c is basically no problem, but depending on the material of the film 100 and the like, it may cause a step mark. Therefore, the cutting machine 50 is provided with a second end mill 80 on the downstream side of the end mill 58, and the second end mill 80 is used to perform cutting again so that the bent portion of the side edge 12c has a smooth curved surface. You can also As this 2nd end mill 80, as shown in FIG. 9, it is good to use what has the outer peripheral surface used as a curve shape toward a front end side. By making the side edge 12 c of the stepped portion 12 curved, it is possible to more reliably prevent the step mark from being generated on the film 100.

  Although not shown, instead of providing the second end mill 80 in the cutting machine 50, a polishing disk or the like may be provided to chamfer the bent portion of the side edge 12c. Note that the second end mill 80, the polishing disk, and the like are not necessarily provided in the cutting machine 50, and may be provided in another cutting machine disposed on the downstream side of the cutting machine 50.

  Furthermore, instead of providing the second end mill 80 and the like in addition to the end mill 58, the side edge 12 c of the stepped portion 12 can be curved with one end mill 58 by changing the shape of the end mill 58. For example, as shown in FIG. 10, it is preferable to use an end mill 58 having a taper portion 58a whose diameter decreases in a curved shape toward the distal end side on the outer peripheral surface thereof.

  Further, for example, as shown in FIG. 11, an end mill 58 having a tapered portion 58a that linearly decreases in diameter toward the tip end side can be used on the outer peripheral surface thereof. The inclination angle (taper angle) of the linear taper portion 58a is set to, for example, 1-3 degrees. In the case of the end mill 58 shown in FIG. 11, the bent portion of the side edge 12 c of the stepped portion 12 remains a little. However, since the angle of the bent portion can be increased, it is possible to appropriately prevent the step mark from being generated on the film 100 even in the end mill 58 shown in FIG.

  Further, in the above-described embodiment, only the stepped portion 12 is formed on the outer peripheral surface of the winding core 10, but as shown in FIG. 12, the cutter is guided to the outer peripheral surface of the winding core 10. The guide groove 16 can also be formed. The guide groove 16 is formed on the bottom surface 12 b along the side surface 12 a of the stepped portion 12 and extends over the entire axial length of the winding core 10. The depth of the guide groove 16, that is, the distance from the bottom surface of the guide groove 16 to the bottom surface 12b of the stepped portion 12 is, for example, 0.5-1.5 mm, and the width of the guide groove 16 is, for example, 0.5-1. 5 mm. The guide groove 16 is formed so that the front end of the film 100 can be properly brought into contact with the side surface 12a of the stepped portion 12 when the front end of the film 100 is not parallel to the axial direction of the winding core 10. It is used to cut off the excess part of the sheet with a cutter.

  When such a guide groove 16 is formed, as shown in FIG. 12, an end mill 58 having a hook-shaped protrusion 58b at its tip may be used. By using the end mill 58 shown in FIG. 12, one end mill 58, that is, the stepped portion 12 and the guide groove 16 can be simultaneously formed by a single cutting process, so that the cutting process can be simplified or made efficient. Therefore, the manufacturing cost of the core 10 having the step portion 12 and the guide groove 16 can be reduced.

  As shown in FIG. 13, the connecting portion 12d between the side surface 12a and the bottom surface 12b of the step portion 12 formed on the winding core 10 may have an arc shape (R shape). Thereby, the strength of the stepped portion 12 (and the winding core 10) can be improved. In this case, an end mill 58 having a curved surface portion 58c at the tip thereof may be used.

  Furthermore, a tapered portion 58a as shown in FIG. 10 or 11 can be formed on the outer peripheral surface of the end mill 58 shown in FIG.

  As described above, the stepped portion 12 having various shapes can be formed by arranging the end mill 58 sideways and appropriately changing the outer peripheral surface shape of the end mill 58. Further, the step 12 and the guide groove 16 can be formed simultaneously. That is, by arranging the end mill 58 so that its axis extends along the tangential direction of the outer peripheral surface of the original tube 102, variations in cutting work are increased.

  However, the end mill 58 may be disposed vertically, that is, with its axis extending along the thickness direction of the original tube 102. In this case, although variations in the cutting process are reduced, the axial direction of the end mill 58 and the direction in which the end mill 58 is pressed against the original pipe 102 coincide with each other, so that the end mill 58 itself is less likely to be shaken.

  In the above-described embodiment, the two upper and lower fixing rollers including the supporting roller 60 and the pressing roller 62 are provided on the upstream side and the downstream side of the end mill 58. Three or more fixing rollers may be provided. In the case where the upper and lower fixing rollers are added, it is preferable that the upper and lower fixing rollers have three to six stations. In this way, by adding the upper and lower fixing rollers, the displacement of the original tube 102 can be suppressed more appropriately.

  When the number of the upper and lower fixing rollers is three, it is preferable that the upstream side of the end mill 58 is one and the downstream side of the end mill 58 is two. This is because the operating vibration in the take-up machine 40 or the cutting machine 42 has a great influence on the displacement of the original pipe 102. By adding an upper and lower fixing roller on the downstream side of the end mill 58, the original pipe is more effectively used. This is because the displacement of 102 can be suppressed. Similarly, when the upper and lower fixing rollers have five stations, it is preferable that the upstream side of the end mill 58 has two stations and the downstream side of the end mill 58 has three stations.

  As an example, FIG. 14 shows a cutting machine 50 with four upper and lower fixing rollers. In addition to the configuration of the cutting machine 50 shown in FIG. 5, the cutting machine 50 shown in FIG. 14 has an upstream side of the upstream left and right fixing rollers 64 and a downstream side of the downstream left and right fixing rollers 64. For each, a vertical fixing roller constituted by a support roller 60 and a pressing roller 62 is added. That is, two upper and lower fixing rollers are provided for each of the upstream side and the downstream side of the end mill 58. The four pressing rollers 62 are integrated with the end mill 58 and the motor 66 by a support frame 68 or the like to constitute an upper unit 70, and the entire upper unit 70 is arranged along the support shaft 74 by a lifting cylinder 72. The height can be adjusted.

  Further, in the above-described embodiment, the V-groove type press roller is used as the press roller 62, but a flat type press roller can also be used as the press roller. In this case, the two flat-type press rollers are arranged so as to extend in an oblique direction so as to correspond to the surface of the V-groove of the V-groove presser roller, and the direction in which the step portion 12 is formed. A pressing force is applied. Also in this case, the position where the pressing roller contacts the original tube 102 is a position shifted from the step portion 12 by a predetermined angle.

  Furthermore, in the above-described embodiment, the step portion 12 is formed by cutting the upper portion of the original tube 102, but the circumferential position of the outer peripheral surface of the original tube 102 forming the step portion 12 is particularly limited. Not. For example, the stepped portion 12 may be formed by cutting the side portion or bottom portion of the original tube 102 using the end mill 58. In this case, a supporting roller that presses the original tube 102 from below, a right presser roller or a left presser roller that presses from the left and right, etc., press the original tube 102 so that a pressing force acts in the direction in which the stepped portion 12 is formed. Functions as a presser roller. Also in this case, the position where the pressing roller contacts the original tube 102 is a position shifted from the step portion 12 by a predetermined angle.

  In the above-described embodiment, the pressing roller 62 presses the original tube 102 from the direction in which the stepped portion 12 is formed, but the present invention is not limited to this. For example, when the step portion 12 is formed by cutting the upper portion of the original tube 102, a V-groove type press roller is adopted as the right press roller and the left press roller, and the right press roller and the left press roller You may make it hold | suppress the original pipe | tube 102 so that a pressing force may act with respect to the direction which forms the level | step-difference part 12. FIG. That is, the V-groove type pressing roller that presses the original tube 102 from a direction other than the direction in which the stepped portion 12 is formed is pressed against the direction in which the stepped portion 12 is formed. It may be made to function as. Also in this case, the position where the pressing roller contacts the original tube 102 is a position shifted from the step portion 12 by a predetermined angle.

  However, the presser roller that presses the original tube 102 so that the pressing force acts in the direction in which the stepped portion 12 is formed does not necessarily need to contact the original tube 102 at a position shifted from the stepped portion 12 by a predetermined angle. In some cases, the original tube 102 may be pressed so as to contact the portion 12.

  Further, in the above-described embodiment, the cutting process for forming the stepped portion on the outer peripheral surface of the original tube 102 is continuously performed in-line with the extrusion molding process. ). Even when the cutting process is performed in outline, the cutting machine 50 illustrated in FIGS. 5 and 14 may be used.

  When performing the cutting process in outline, first, a long cylindrical original tube 102 of about 3 to 4 m is manufactured using a general cylindrical tube extrusion molding apparatus. Subsequently, the stepped portion 12 extending along the axial direction with respect to the outer peripheral surface of the original tube 102 is formed by using the cutting machine 50. Then, the core 10 is manufactured by cutting the original tube 102 in which the stepped portion 12 is formed into a predetermined length using a cutting machine or the like. By performing the cutting process in this way, the degree of freedom in the manufacturing process is increased.

  It should be noted that the specific numerical values such as the dimensions mentioned above are merely examples, and can be appropriately changed according to the needs of product specifications and the like.

DESCRIPTION OF SYMBOLS 10 ... Winding core 12 ... Step part 30 ... Winding core manufacturing apparatus 50 ... Cutting machine 58 ... End mill 58a ... End mill taper part 58b ... End mill projection part 60 ... Support roller 62 ... Pressing roller 64 ... Left and right fixing roller 100 ... core 102 ... original tube

Claims (3)

A method of manufacturing a core in which a film is wound around an outer peripheral surface,
An extrusion process for producing a cylindrical raw tube by extruding a thermoplastic resin using an extrusion apparatus; and
Forming a step portion extending along the axial direction with respect to the outer peripheral surface of the original tube using a cutting machine,
The cutting machine includes a pressing roller that presses the original pipe so that a pressing force acts on a direction in which the stepped portion is formed.
The cutting machine is arranged on a line of the extrusion process of the original pipe, the arrangement position is upstream of the take-up machine provided in the extrusion apparatus,
The said cutting process is a manufacturing method of the winding core performed continuously with the said extrusion molding process. A method of manufacturing a core in which a film is wound around an outer peripheral surface,
An extrusion process for producing a cylindrical raw tube by extruding a thermoplastic resin using an extrusion apparatus; and
Forming a step portion extending along the axial direction with respect to the outer peripheral surface of the original tube using a cutting machine,
The cutting machine includes a pressing roller that presses the original pipe so that a pressing force acts on a direction in which the stepped portion is formed.
The cutting machine includes an end mill arranged so that an axis extends along a tangential direction of the outer peripheral surface of the original pipe,
The outer peripheral surface of the said end mill is a manufacturing method of a winding core which has a taper part which becomes a diameter small toward the front end side. The end portion of the end mill has a protrusion formed in a bowl shape,
The method of manufacturing a winding core according to claim 2 , wherein in the cutting step, a guide groove for guiding the cutter is formed simultaneously with the stepped portion by the end mill.

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