Patent Grant
7475844
The present invention relates to a web winding device for simultaneously winding a plurality of webs around a plurality of winding cores respectively mounted on a winding shaft, and a spacer mounted to the winding shaft.
In a production line of a photosensitive film, a magnetic tape, or the like, a broad raw material web such as paper or film is subjected to various kinds of treatment including coating treatment and drying treatment using a photosensitive material and a magnetic material, and then the raw material web is wound in a roll shape (raw material web coil). The raw material web coil is set to a web cutting device. In the web cutting device, first of all, the raw material web drawn from the raw material web coil is cut into a plurality of narrow webs by a slitter. Next, the plurality of narrow webs thus cut are simultaneously wound in a roll shape by a web winding device disposed in a downstream side from the slitter in a web transporting direction, thus a product web coil is obtained.
Two winding shafts are generally disposed in the web winding device. The plurality of narrow webs cut by the slitter are simultaneously wound around after being allocated alternately to each other of the two winding shafts such that the side ends of the narrow webs are not overlapped with each other during winding of the webs. A plurality of winding cores for winding the respective narrow webs and a plurality of approximately cylindrical spacers are mounted to each of the winding shafts so as to be arranged in a line alternately. The spacer defines a position of each of the winding cores such that each winding core corresponds to a position of each allocated narrow web (see Patent Document 1).
Upon finishing the winding of the narrow web, the winding core around which the narrow web is wound is removed from the winding shaft, and a new winding core is set to the winding shaft. Accordingly, in general, the winding cores and the spacers are detachably attached to the winding shaft so as to be removed easily from the winding shaft. Therefore, a stopper for regulating the moving of the winding cores and the spacers in the axial direction is provided at one end of the winding shaft, and the winding cores and the spacers are biased toward the stopper by a predetermined biasing force. Thereby, the spacers abut on both side surfaces of each winding core, and the position of the winding core in the axial direction is defined. Further, chuck claws or the like to be in pressure contact with an inner peripheral surface of the winding core are disposed at the winding shaft. When both winding shafts are rotated, the chuck claw and the inner peripheral surface of the winding core are in sliding contact with each other, and rotational force of the winding shafts is transmitted to the winding core. When the narrow web is wound, the winding core is rotated at a peripheral velocity corresponding to the transporting speed of the web. Therefore, when the winding shaft is rotated faster than the winding core, there occurs sliding between the winding shaft and the winding core due to the rotational difference, and then winding tension in accordance with the sliding coefficient of friction thereof is generated (see Patent Documents 2 and 3).
There is thickness variation in a width direction of the raw material web. Therefore, when the narrow web is wound around each winding core mounted to the winding shaft, there arises a difference in winding diameter between the respective product web coils. When the winding diameter of a product coil is larger than an adjacent product coil rotated at the same rotational speed, a peripheral velocity W1 of one product web coil having a larger winding diameter becomes faster than a peripheral velocity W2 of the other product web coil. At this time, each winding core is rotated while being in sliding contact with the winding shaft (chuck claw) as described above. Therefore, there occurs further sliding between the winding core and the winding shaft of the product web coil having a larger diameter. The peripheral velocity W1 is decreased to a level of the peripheral velocity W2.
However, the spacer abuts on both side surfaces of the respective winding cores as described above. The spacer is rotated at the same speed as that of the winding shaft since the spacer is in contact with the winding shaft by its weight. Accordingly, torque in a rotational direction of the winding shaft from the spacer is applied to the winding core abutting on the spacer in accordance with contact resistance therebetween and the rotational speed of the spacer. The torque prevents the decelerating of the peripheral velocity W1. Since the torque is varied, the winding tension on the narrow web becomes unstable.
Further, when the biasing force for biasing the winding core and the spacer toward the stopper is strong, there occurs no sliding between the winding core and the spacer, and therefore the winding cores sandwiching the spacer are substantially connected to each other. Therefore, the product web coils having a winding diameter different from each other are rotated at the same rotational speed. Accordingly, depending on the winding diameter, the peripheral velocity of each product web coil will be faster or slower than the appropriate velocity. As a result, the tightly wound product web coil due to the increase in the winding tension and the loosely wound product web coil due to the decrease in the winding tension are formed.
An object of the present invention is to provide a web winding device capable of winding webs around each winding core positioned in a winding shaft by a spacer with a stable winding tension, and a spacer used therefor.
To achieve the above object, a web winding device of the present invention includes a winding shaft extending along a width direction of a web, a plurality of winding cores arranged in a line in an axial direction of the winding shaft so as to be rotatable around the winding shaft, a rotation transmission member provided at the winding shaft and being in sliding contact with an inner peripheral surface of the winding core at the time of rotating the winding shaft, and a plurality of spacers mounted to the winding shaft so as to be alternate with a plurality of the winding cores, for positioning each winding core in the axial direction. The spacer includes an approximately cylindrical spacer body abutting on the winding shaft, a contact member protruding from a spacer body side surface opposed to the winding core and abutting on the winding core, and a holding member for holding the contact member rotatably around the spacer body.
It is preferable that the contact member has an annular shape with its center at a rotational axis line of the winding shaft, and held by the holding member so as to be rotatable around the rotational axis line relative to the spacer body. Further, the holding member preferably includes an approximately annular holding recess formed on the spacer body side surface opposed to the winding core with its center at the rotational axis line, and a plurality of rollers disposed between a bottom surface of the holding recess and the contact member.
Preferably, the spacer body, the contact member, and the rollers are made from any of one of resin, MC material, and MC nylon material. Further, it is preferable that a plurality of the winding shafts are disposed in the web winding device, and a plurality of the webs are allocated to the respective winding shafts and wound around the winding core mounted to each of the winding shaft.
A spacer of the present invention is mounted to a winding shaft so as to be alternate with each of a plurality of winding cores, and defines a position of the winding core mounted to the winding shaft in an axial direction of the winding shaft. The spacer includes an approximately cylindrical spacer body abutting on the winding shaft, a contact member protruding from a spacer body side surface opposed to the winding core and abutting on the winding core, the contact member having an approximately annular shape with its center at a rotational axis line of the winding shaft, a holding recess formed on the spacer body side surface opposed to the winding core and having an approximately annular shape with its center at the rotational axis line, for holding the contact member rotatably around the rotational axis line of the winding shaft, and a plurality of rollers disposed between a bottom surface of the holding recess and the contact member.
Preferably, the spacer body, the contact member, and the rollers are made from any of one of resin, MC material, and MC nylon material.
The web winding device of the present invention includes a winding shaft extending along a width direction of a web, a plurality of winding cores arranged in a line in an axial direction of the winding shaft so as to be rotatable around the winding shaft, a rotation transmission member provided at the winding shaft and being in sliding contact with the inner peripheral surfaces of the winding cores at the time of rotating the winding shaft, and a plurality of spacers mounted to the winding shaft so as to be alternate with a plurality of the winding cores, for positioning each winding core in the axial direction. Further, the spacer includes an approximately cylindrical spacer body abutting on the winding shaft, a contact member protruding from a spacer body side surface opposed to the winding core and abutting on the winding core, and a holding member for holding the contact member rotatably around the spacer body. Accordingly, each of the winding cores on the winding shaft can be rotated independently from each other without being affected by the spacers, and the winding tension of each winding core for the web can be stabilized within the predetermined range. As a result, it is possible to stabilize the winding shape and winding hardness of the wound web coil.
Further, the contact member has an annular shape with its center at a rotational axis line of the winding shaft, and is held by the holding member so as to be rotatable around the rotational axis line relative to the spacer body. Accordingly, it is possible to efficiently prevent the transmission of torque to the winding core from the spacer rotated around the rotational axis line of the winding shaft.
The holding member includes an approximately annular holding recess formed on the spacer body side surface opposed to the winding core with its center at the rotational axis line, and a plurality of rollers disposed between a bottom surface of the holding recess and the contact member. Accordingly, it is possible to efficiently prevent the transmission of torque from the spacer to the winding core.
The spacer body, the contact member, and the rollers are made from any of one of resin, MC material, and MC nylon material. Accordingly, it is possible to reduce the weight of the web winding device.
A plurality of the winding shafts are disposed in the web winding device, and a plurality of the webs are allocated to each of the winding shafts and wound around the winding core mounted to each of the winding shafts. Accordingly, it is possible to prevent the side ends of the webs adjacent from touching/overlapping with each other.
Moreover, the spacer of the present invention is mounted to a winding shaft so as to be alternate with each of a plurality of winding cores and defines a position of each winding core mounted to the winding shaft in a direction of the winding shaft. The spacer includes an approximately cylindrical spacer body abutting on the winding shaft, a contact member protruding from the spacer body side surface opposed to the winding core and abutting on the winding core, the contact member having an approximately annular shape with its center at a rotational axis line of the winding shaft, a holding recess formed on the spacer body side surface opposed to the winding core and having an approximately annular shape with its center at the rotational axis line, for holding the contact member rotatably around the rotational axis line of the winding shaft, and a plurality of rollers disposed between a bottom surface of the holding recess and the contact member. Therefore, in a similar manner, each of the winding cores on the winding shaft can be rotated independently from each other without being affected by the spacers, and the winding tension on each winding core for the web can be stabilized within the predetermined range.
The spacer body, the contact member, and the rollers are made from any of one of resin, MC material, and MC nylon material. Accordingly, it is possible to reduce the weight of the spacer.
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As shown in
The raw material web supplying device 13 includes a coil rotational shaft 18, a holder (not shown), and a motor (not shown). A raw material web coil 17 obtained by winding the raw material web 11 in a roll shape is set to the coil rotational shaft 18. The holder holds the coil rotational shaft 18 rotatably. The motor is connected to the coil rotational shaft 18. When the coil rotational shaft 18 is rotated by the motor clockwise in the drawing, the raw material web 11 is drawn from the raw material web coil 17. The drawn raw material web 11 is transported to a slitter 14 by a suction drum 20 disposed in a downstream side from the raw material web coil 17 in a transporting direction of the web.
The slitter 14 includes a plurality of upper rotatable cutting blades 21 and lower rotatable cutting blades 22, slitter shafts 23, holders (not shown), and a motor for rotating cutting blades (not shown). The upper rotatable cutting blades 21 and lower rotatable cutting blades 22 are disposed so as to sandwich the raw material web 11 continuously transported from the raw material web coil 17. The upper rotatable cutting blades 21 and lower rotatable cutting blades 22 are fixed to the slitter shafts 23. The holder holds the both slitter shafts 23 rotatably. The motor for rotating cutting blade is connected to the both slitter shafts 23.
The rotatable cutting blades 21, 22 are fixed to the slitter shaft 23 at an interval which is equal to a width of the product web 11a by respective spacers not shown in the drawing. When the raw material web 11 is transported between the upper rotatable cutting blades 21 and the lower rotatable cutting blades 22 from the raw material web coil 17, the upper rotatable cutting blades 21 rotate clockwise and the lower rotatable cutting blades 22 rotate counterclockwise direction in the drawing. Thereby, the raw material film 11 is cut into a plurality of product webs 11a. The product webs 11a thus cut are continuously transported to the web winding device 15.
The web winding device 15 simultaneously winds the plurality of product webs 11a into a coil shape to form the product web coils (hereinafter referred to as web coils) 25. The web winding device 15 includes a first winding shaft 26 and a second winding shaft 27 disposed below the first winding shaft 26 in the vertical direction. The product webs 11a cut by the slitter 14 are allocated, one by one, to the first winding shaft 26 and the second winding shaft 27 in an alternate manner with use of guide rollers 28 and transporting guides not shown in the drawing. For example, when reference numerals 1, 2, 3, . . . , and N are given in this order to the product webs 11 from the right side in the drawing in this embodiment, the product webs 11a having odd reference numbers are allocated to the first winding shaft 26, and the product webs 11a having even reference numbers are allocated to the second winding shaft 27. Thereby, it is possible to prevent the side ends of the adjacent product webs 11a from touching/overlapping with each other at the time of winding the webs.
As shown in
The movable collar 32 is biased toward the fixed collar 31 by a biasing device 35 (including a cylinder, a rod, a swing arm, and the like). Thereby, the winding cores 33 and the spacers 34 are arranged so as to be adjacent to each other without clearance in the axial direction of the first winding shaft 26.
The spacer 34 abuts on both side surfaces of each winding core 33 to define the position of each winding core 33 in the axial direction. The length of the spacer 34 is equal to the width of the product web 11a. Accordingly, it is only required to adjust the mounting position of the fixed collar 31 in order to position the winding cores 33 in accordance with the position of the allocated product webs 11a. Note that the spacer 34 is described in detail later.
A motor 37 is connected to one end of the first winding shaft 26 through a driving connection mechanism not shown in the drawing. The motor 37 rotates the first winding shaft 26 at the time of winding the product web 11a. In this embodiment, each of the winding cores 33 is attached to the first winding shaft 26 in a rotatable and slidable manner so that a web coil 25 can be removed together with the winding core 33. Therefore, the first winding shaft 26 is provided with a rotation transmission mechanism 38 for transmitting rotational force of each shaft to the winding core 33. An air joint 39 is movably attached to the other end of the first winding shaft 26. An air blower 41 is connected to the first winding shaft 26 through the air joint 39 and an air pipe 40.
As shown in
When the first shaft 26 is rotated in a state where the chuck claw 43 is in pressure contact with the inner peripheral surface of the winding core 33, the pressing surface 42 of the chuck claw 43 and the inner peripheral surface of the winding core 33 is in sliding contact with each other. Thereby, the rotation of the shaft is transmitted to the winding core 33. As described above, the winding core 33 is rotated at the peripheral velocity corresponding to a transporting speed of the product web 11a when winding the product web 11a. Accordingly, when the first winding shaft 26 is rotated faster than the winding core 33, slipping occurs between the first winding shaft 26 and the winding core 33 due to a rotational speed difference, thus causing a winding tension in accordance with the sliding coefficient of friction thereof. At the end of winding, the air supply from the air blower 41 to the claw transporting mechanism is stopped to interrupt the pressurization of the chuck claw 43. Thereby, it becomes possible to remove the winding cores 33 from the winding shafts 26 and 27. When the winding core 33 is to be removed from the first winding shaft 26, the air joint 39 and the side wall 30 in the right side of
As described above, the thicknesses of the product webs 11a wound around the winding core 33 are not always equal to each other. Therefore, as shown in
At this time, the spacers 34 abutting on both surfaces of the winding cores 33 of the web coils 25a and 25b rotate at the approximately same speed as the first winding shaft 26, that is, at the speed faster than that of the winding core 33. Therefore, as described above, torque in the rotational direction of the winding shaft is applied to the winding core 33 of the web coil 25a by the spacer 34, and thereby the peripheral velocity W1 of the web coils 25a is prevented from decreasing. Since the torque is varied in accordance with the frictional resistance between the spacer 34 and the winding core 33 and the rotational speed of the spacer 34, the winding tension of each web coil 25 for the product web 11a becomes unstable. Further, in a case where biasing force for biasing the winding core 33 and the spacer 34 toward the fixed collar 31 is strong, the web coils 25a and 25b are rotated at the same rotational speed. Therefore, the peripheral velocity of the web coil 25a having a larger winding diameter is faster than its appropriate speed, and the peripheral velocity of the web coil 25b having a smaller winding diameter is slower than its appropriate speed. As a result, the tightly wound web coil 25a due to the increase in the winding tension and the loosely wound web coil 25b due to the decrease in the winding tension will be formed.
In view of the above, in this embodiment, in order to stabilize the winding tension on the product web 11a on each winding core 33, the shape of the spacer 34 is a thrust bearing. Thereby, it is possible to prevent transmission of the torque from the spacer 34 to the winding core 33, and rotate each winding core 33 independently. Hereinafter, the spacer 34 of the present invention is described by referring to
The spacer 34 is mainly composed of an approximately cylindrical spacer body 57 being in contact with the first winding shaft 26, and approximately annular contact members 58 protruding from both side surfaces of the spacer body 57 and abutting on the side surfaces of the winding cores 33 adjacent to the spacer 34, that is, three members in total. The spacer body 57 is made from resin, MC material (metal ceramics composite material), MC (monomer cast) nylon material, or the like for reducing the weight of the first winding shaft 26. The spacer body 57 holds the contact members 58 rotatably relative to the rotating center line C of the first winding shaft 26. Therefore, an approximately annular contact member holding recess 59 is formed to rotatably hold the contact members 58 on both side surfaces of the spacer 57.
The contact member 58 is also made from resin, MC material, MC nylon material, or the like for reducing the weight of the first winding shaft 26. The contact member 58 has a contacting surface 60 (see
A plurality of spherical resin rollers (ball bearings) 62 are disposed at the same interval between the contact member 58 and a bottom surface of the contact member holding recess 59. Note that, although the resin rollers 62 are used for lightening of the first winding shaft 26 in this embodiment, the present invention is not limited thereto, and the rollers made from MC material or MC nylon material also may be used.
The respective resin rollers 62 are rotatably held by retainers 65 and abut on guide recesses 63 respectively formed on the bottom surface of the contact member holding recess 59 and the contact member 58. The retainer 65 includes rotational shafts/rods provided so as to be parallel to a radial direction of the first winding shafts 26, 27 at the same interval. The resin rollers 62 are rotated around the respective rotational shafts/rods. Here, the radial direction is a direction perpendicular to the rotational center line C. Additionally, a stopper 67 (see
With the above structure, even when one of the spacer body 57 and the contact member 58 is rotated, each of the resin rollers 62 is rotated along the guide recesses 63 and 64, respectively, and therefore only slightly torque caused by the rotation of the resin roller 62 is applied to the other one. Accordingly, even when the biasing mechanism 35 biases the winding cores 33 and the spacers 34 toward the fixed collar 31, each of the winding cores 33 can be rotated independently.
As a result, when the peripheral velocity W1 of the web coil 25a (see
Further, even when the biasing force by the biasing mechanism 35 is strong, each contact member 58 formed on both side surfaces of the spacer body 57 rotates relative to the spacer body 57. Therefore, each of the winding cores 33 rotates independently, and the web coils 25 having a winding diameter different from each other don't rotate at the same rotational speed.
As described above, since the spacer 34 has a so-called thrust bearing shape in this embodiment, it is possible to prevent transmission of the torque between the winding core 33 and the spacer 34. Therefore, it is possible to rotate each of the winding cores 33 independently, and stabilize the winding tension on the product webs 11a around the winding cores 33.
Next, an operation of this embodiment is described. Before starting driving of the web cutting device 10, the raw material web coil 17 is set to the coil rotational shaft 18 of the raw material web supplying device 13. Further, the winding cores 33 and spacers 34 are mounted alternately to the first and second shafts 26, 27 of the web winding device 15, respectively. Next, the biasing mechanism 35 biases the winding core 33 and the spacers 34 toward the fixed collar 31. Upon finishing the preliminary works described above, an operator starts driving of the web cutting device 10 and drives the air blower 41 to pressurize the chuck claw 43 against the inner peripheral surface of the winding core 33 (see
Rotatable cutting blades 21 and 22 start rotating respectively before the raw material web 18 transported from the raw material web coil 17 reaches between the rotatable cutting blades 21 and 22 of the slitter 14. Thereby, the raw material film 11 is cut into the plurality of product webs 11a. Further, the product webs 11a thus cut are allocated in an alternate manner, one by one, to the first winding shaft 26 and the second winding shaft 27 of the web winding device 15.
The front ends of the product webs 11a allocated to the first and second winding shafts 26 and 27 respectively are wound around the winding cores 33 by the web winding device not shown in the drawing. Next, upon starting the rotation of the motor 37, both winding shafts 26 and 27 are rotated. Upon rotation of both winding shafts 26 and 27, the pressing surface 42 of each chuck claw 43 and the inner peripheral surface of the winding core 33 are in sliding contact with each other, and thereby the rotational force of the shafts are transmitted to the winding core 33. Both winding shafts 26 and 27 are rotated faster than the winding core 33 rotating at the peripheral velocity corresponding to the transporting speed of the product web 11a. Due to the rotational difference, the winding tension on the product web 11a wound around the winding core 33 is generated.
In this embodiment, the spacer 34 is divided into three sections including the spacer body 57 being in contact with the peripheral surface of the winding shaft 26 or 27, and the contact members 58 being in contact with the winding cores 33 on both sides of the spacer body 57. The spacer body 57 holds the contact member 58 such that the contact members 58 rotate relative to the spacer body 57. Accordingly, it is possible to prevent the transmission of torque between the winding core 33 and the spacer 34 almost completely, and rotate each winding core 33 (web coil 25) independently.
Consequently, when the peripheral velocity W1 of the web coil 25a (see
Upon finishing winding of the product web coil 25, the rotation of the motor 37 is stopped, and the supplying of high-pressure air from the air blower 41 is also stopped, thus interrupting the pressure contact between the chuck claw 43 and the winding core 33. Next, the web cutting device not shown in the drawing cuts a predetermined position of each of the product webs 11a. Upon finishing cutting of the product web 11a, the operator removes the web coils 25 together with the winding cores 33 from the winding shafts 26, 27, and mounts new winding cores 33 and the spacers 34 to the winding shafts 26, 27 in an alternate manner. Then, the peripheral surface of the new winding core 33 is pressed by the chuck claw 43, and the front end of the product web 11a is wound around the core by the web winding device not shown in the drawing. Hereinafter, the product web coil 25 is wound in the same manner.
Note that, in this embodiment, in order to prevent the transmission of torque between the winding core 33 and the spacer 34, the spacer body 57 holds the approximately annular contact member 58 such that the contact member 58 rotates relative to the spacer body 57. However, the present invention is not limited thereto. Any member can be adopted as long as the member abuts on the side surface of the winding core 33 and be held rotatably by the spacer body 57 in accordance with the rotation of the winding core 33. For example, instead of the contact member 58, the approximately cylindrical or spherical resin roller 70 may be used. Hereinafter, by referring to
As shown in
Further, although the raw material web 11 is cut by the slitter 14 into eight sheets of the product web 11a, and four winding cores 33 are mounted on the first and second shafts 26, 27 respectively in this embodiment, the present invention is not limited thereto. The number of sheets of the product web 11a and the number of the winding cores 33 and the spacers 34 to be mounted can be varied as needed.
Note that, although the product webs 11a obtained by being cut by the slitter 14 are allocated one by one to the two winding shafts 26, 27 in an alternate manner in this embodiment, the present invention is not limited thereto. The number of winding shafts may be three or more, and the product webs 11a are allocated to the respective winding shafts.
[Experiment]
In order to provide evidence to prove the effect of the present invention, in both “Comparative Example” in which a conventional spacer was mounted to the first winding shaft 26 and “Example” in which the spacer 34 of the present invention was mounted to the first winding shaft 26, the product web 11a was wound around the plurality of winding cores 33 disposed in the axial direction of the winding shafts, and the winding tension was measured and the measurement results were compared.
The kind of the product web 11a (the raw material web 11), the set value of air pressure of the air blower 41, the rotational speed of the motor 37, the winding cores 33 at which winding tension is measured, a tension measuring device were common between “Comparative Example” and “Example”. Only the spacer to be used was different therebetween. Further, when measuring the winding tension at each winding core 33, winding tension was measured at plural points in the axial direction of the winding shaft, and average value (AVE), maximum value (MAX), and minimum value (MIN) of the winding tension was obtained at each winding core 33. Further, for comparison, a certain reference value (not shown publicly) of the winding tension, which was common between “Comparative Example” and “Example”, was designated by the inventor of the present invention and considered as 100%, and then the measurement result of the winding tension at each winding core 33 is shown relative to the reference value in a graph. The measurement result of “Comparative Example” is shown in a graph of
As shown in
The present invention is applicable to various kinds of web winding devices capable of simultaneously winding various kinds of narrow webs such as a protective film for liquid crystal display, PET (Polyethylene Terephthalate) film, magnetic recording tape, photo film, adhesive agent tape, or the like.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-082627 | Mar 2005 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2006/305384 | 3/17/2006 | WO | 00 | 8/21/2007 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2006/101043 | 9/28/2006 | WO | A |
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| 62-51538 | Mar 1987 | JP |
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| Number | Date | Country | |
|---|---|---|---|
| 20080149756 A1 | Jun 2008 | US |
