U.S. patent application number 14/218447 was filed with the patent office on 2014-07-17 for tape winding apparatus.
This patent application is currently assigned to FUJIFILM CORPORATION. The applicant listed for this patent is FUJIFILM Corporation. Invention is credited to Takahisa IZUMIDA, Hiroki OHTSU.
Application Number | 20140197266 14/218447 |
Document ID | / |
Family ID | 41087909 |
Filed Date | 2014-07-17 |
United States Patent
Application |
20140197266 |
Kind Code |
A1 |
IZUMIDA; Takahisa ; et
al. |
July 17, 2014 |
TAPE WINDING APPARATUS
Abstract
A tape winding apparatus includes: a rotating device configured
to rotate a wind-up core for winding a tape into a roll which
defines a tape roll; a push roller configured to be pressed against
the tape roll, the push roller contacting with and rolling on an
outer periphery of the tape roll at a tape feeding position where
the tape is fed onto the tape roll; a feeding direction control
guide arranged upstream from the push roller as viewed in a running
direction of the tape and configured to control a tape-feeding
direction of the tape that is fed onto the tape roll; and a
movement device configured to move at least one of the push roller
and the feeding direction control guide such that the tape-feeding
direction conforms with a tangential direction of the tape roll at
the tape feeding position.
Inventors: |
IZUMIDA; Takahisa;
(Kanagawa, JP) ; OHTSU; Hiroki; (Kanagawa,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
FUJIFILM CORPORATION
Tokyo
JP
|
Family ID: |
41087909 |
Appl. No.: |
14/218447 |
Filed: |
March 18, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13569967 |
Aug 8, 2012 |
8702028 |
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|
14218447 |
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|
12406389 |
Mar 18, 2009 |
8272590 |
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13569967 |
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Current U.S.
Class: |
242/547 |
Current CPC
Class: |
B65H 18/26 20130101;
B65H 23/038 20130101; B65H 2404/43 20130101 |
Class at
Publication: |
242/547 |
International
Class: |
B65H 18/26 20060101
B65H018/26; B65H 23/038 20060101 B65H023/038 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 24, 2008 |
JP |
2008-075548 |
Claims
1. A method for producing a roll of tape wound on a wind-up core
comprising: a setting step of setting a tape and a wind-up core to
a tape winding apparatus which comprises: a rotating device
configured to rotate the wind-up core to wind the tape into a tape
roll; a push roller configure to contact with and roll on an outer
periphery of the tape roll at a tape feeding position where the
tape firstly contacts with the tape roll and is fed onto the tape
roll; a feeding direction control guide arranged at a non-contact
position relative to the tape roll and upstream from the push
roller as viewed in a running direction of the tape and configured
to control a tape-feeding direction of the tape that is fed onto
the tape roll, the feeding direction control guide having a
cylindrical guide surface for guiding the tape; and a movement
device configured to move at least one of the push roller and the
feeding direction control guide such that the tape-feeding
direction conforms with a tangential direction of the tape roll at
the tape feeding position, a rotating step of rotating the wind-up
core while guiding the tape by the push roller and the feeding
direction control guide along the tangential direction; and a
moving step of moving the movement device in accordance with a
change in diameter of the tape roll, such that regardless of the
diameter of the tape roll, the tape-feeding direction determined by
positions of the push roller and the feeding direction control
guide conforms with the tangential direction.
2. The method according to claim 1, wherein the movement device
comprises: a swing arm supporting the push roller and configured to
be swingable about a central axis of the cylindrical guide surface
of the feeding direction control guide; a slide stage on which the
swing arm is swingably supported while supporting the feeding
direction control guide; a spring having a first end engaged with
the swing arm and a second end engaged with the slide stage and
configured to apply a pressing force to the push roller; a rail
along which the slide stage is guided; an actuator for moving the
slide stage along the rail; and a controller configured to control
the actuator to maintain the tangential direction of the tape roll
at the tape feeding position, and wherein the moving step
comprising moving the slide stage along the rail by means of the
actuator in accordance with the change in diameter of the tape
roll.
3. The method according to claim 1, wherein the movement device
comprises: a swing arm supporting the push roller and configured to
be swingable about a central axis of the cylindrical guide surface
of the feeding direction control guide; a first longitudinal swing
arm member on which the swing arm is swingably supported by the
feeding direction control guide; a spring having a first end
engaged with the swing arm and a second end engaged with the first
longitudinal swing arm member and configured to apply a pressing
force to the push roller; an actuator for swinging the first
longitudinal swing arm member; and a controller configured to
control the actuator to maintain the tangential direction of the
tape roll at the tape feeding position, and wherein the moving step
comprising moving the feeding direction control guide via the first
longitudinal swing arm member by means of the actuator in
accordance with the change in diameter of the tape roll.
4. The method according to claim 1, wherein the movement device
comprises: a base on which the feeding direction control guide is
fixed so as not to be movable relative to the wind-up core; a
second longitudinal swing arm member supporting the push roller and
swingably supported on the base; and a spring configured to apply a
swinging force to the second longitudinal swing arm member, wherein
a pivot axis of the second longitudinal swing arm member is
positioned at a midpoint of a line segment connecting a rotation
axis of the wind-up core and a tape contacting point of the feeding
direction control guide at which point the tape contacts with the
cylindrical guide surface of the feeding direction control guide
for guiding the tape toward the tape roll, and wherein the moving
step comprising moving the second longitudinal swing arm member in
accordance with the change in diameter of the tape roll, such that
the push roller moves along a trajectory of a circular arc passing
through the rotation axis of the wind-up core and the feeding
direction control guide.
5. The method according to claim 1, wherein the roll of tape wound
on the wind-up core is a servo-formatted magnetic tape.
6. A method for producing a roll of tape wound on a wind-up core
comprising: a setting step of setting a tape and a wind-up core to
a tape winding apparatus which comprises: a rotating device
configured to rotate the wind-up core to wind the tape into a tape
roll; a push roller configure to contact with and roll on an outer
periphery of the tape roll at a tape feeding position where the
tape firstly contacts with the tape roll and is fed onto the tape
roll; a feeding direction control guide arranged at a non-contact
position relative to the tape roll and upstream from the push
roller as viewed in a running direction of the tape and configured
to control a tape-feeding direction of the tape that is fed onto
the tape roll, the feeding direction control guide having a
cylindrical guide surface for guiding the tape; and a movement
device comprising a swing arm supporting the push roller and
configured to be swingable about a central axis of the cylindrical
guide surface of the feeding direction control guide, and
configured to move at least one of the swing arm and the feeding
direction control guide, relative to the wind-up core, such that
the tape-feeding direction conforms with a tangential direction of
the tape roll at the tape feeding position, a rotating step of
rotating the wind-up core while guiding the tape by the push roller
and the feeding direction control guide along the tangential
direction; and a moving step of moving the movement device in
accordance with a change in diameter of the tape roll, such that
regardless of the diameter of the tape roll, the tape-feeding
direction determined by positions of the push roller and the
feeding direction control guide conforms with the tangential
direction.
7. The method according to claim 6, wherein the movement device
comprises: a slide stage on which the swing arm is swingably
supported while supporting the feeding direction control guide; a
spring having a first end engaged with the swing arm and a second
end engaged with the slide stage and configured to apply a pressing
force to the push roller; a rail along which the slide stage is
guided; an actuator for moving the slide stage along the rail; and
a controller configured to control the actuator to maintain the
tangential direction of the tape roll at the tape feeding position,
and wherein the moving step comprising moving the slide stage along
the rail by means of the actuator in accordance with the change in
diameter of the tape roll.
8. The method according to claim 6, wherein the movement device
comprises: a first longitudinal swing arm member on which the swing
arm is swingably supported by the feeding direction control guide;
a spring having a first end engaged with the swing arm and a second
end engaged with the first longitudinal swing arm member and
configured to apply a pressing force to the push roller; an
actuator for swinging the first longitudinal swing arm member; and
a controller configured to control the actuator to maintain the
tangential direction of the tape roll at the tape feeding position,
and wherein the moving step comprising moving the feeding direction
control guide via the first longitudinal swing arm member by means
of the actuator in accordance with the change in diameter of the
tape roll.
9. The method according to claim 6, wherein the roll of tape wound
on the wind-up core is a servo-formatted magnetic tape.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a Divisional of application Ser. No.
13/569,967, filed Aug. 8, 2012, which is a Divisional of
application Ser. No. 12/406,389 filed Mar. 18, 2009 (now U.S. Pat.
No. 8,272,590), claiming priority based on Patent Application No.
JP 2008-075548 filed Mar. 24, 2008, the contents of all of which
are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a tape winding apparatus,
and more particularly to a tape winding apparatus which can wind a
tape into a roll at high speeds while maintaining a precise and
aligned winding profile.
[0003] It is desirable that a tape-like material such as a magnetic
tape is wound into a roll with a precise and aligned winding
profile. Recently, data is recorded on a magnetic tape having an
extremely narrow track width. Therefore, if the tape edge is not
aligned precisely when it is wound into a roll, there is a
possibility that the magnetic head will not follow a predetermined
track during the recording and/or reading of the data. Further, in
a recent magnetic tape, a tracking servo signal is recorded on a
recording layer during the manufacture of the magnetic tape.
However, if the winding profile of the tape roll is not precisely
aligned before recording the servo signal, the magnetic tape will
shift in a direction of the tape width so that a precise recording
of the servo signal cannot be performed. Moreover, if the winding
profile of the magnetic tape is not aligned, the magnetic tape is
partly subject to deformation and/or the tape edge is susceptible
to damage. These are more likely to occur for a recent magnetic
tape because the thickness of the magnetic tape becomes
thinner.
[0004] The magnetic tape will be wound into a roll with a precise
and aligned winding profile if the wind-up speed is reduced.
However, in order to improve productivity at a production site or
to improve data scan speed on a magnetic tape drive, it is
desirable that the magnetic tape be wound up as fast as
possible.
[0005] There is also a need to improve productivity of tape
products other than magnetic tape.
[0006] Japanese Laid-open Patent Publication No. 62-31645, which
corresponds to U.S. Pat. No. 4,778,119, discloses a magnetic tape
wind-up system for winding up a magnetic tape into a roll shape at
high speeds. In this conventional system, a push roller (i.e., edge
control roller) is pressed against a tape roll that is a tape
having been wound into a roll so that air between the tape roll and
a magnetic tape to be wound around the tape roll is removed. This
can improve preciseness and alignment of the winding profile. The
push roller is supported on a swing arm, to which a position
control roller is also provided to control a feed direction of the
magnetic tape to the tape roll.
[0007] However, because the magnetic tape is wound around the push
roller in the conventional magnetic tape wind-up system, the
tensile force acting on the magnetic tape urges the push roller
away from the tape roll. Therefore, as the wind-up speed is
increased, a variation in the tensile force of the magnetic tape
adversely affects the pressing force of the push roller, so that it
becomes difficult to wind up the magnetic tape into a roll in a
precise and aligned manner.
[0008] In view of the above, the present invention seeks to provide
a tape winding apparatus which can wind a tape at high speeds in a
precise and aligned manner while eliminating an adverse effect on
the push roller due to variation in the tensile force of the
tape.
SUMMARY OF THE INVENTION
[0009] According to the present invention, there is provided a tape
winding apparatus comprising: a rotating device configured to
rotate a wind-up core for winding a tape into a roll which defines
a tape roll; a push roller configured to be pressed against the
tape roll, the push roller contacting with and rolling on an outer
periphery of the tape roll at a tape feeding position where the
tape is fed onto the tape roll; a feeding direction control guide
arranged upstream from the push roller as viewed in a running
direction of the tape and configured to control a tape-feeding
direction of the tape that is fed onto the tape roll; and a
movement device configured to move at least one of the push roller
and the feeding direction control guide such that the tape-feeding
direction conforms with a tangential direction of the tape roll at
the tape feeding position.
[0010] With this configuration of the tape winding apparatus
according to the present invention, the push roller contacts with
the tape roll at the tape feeding position where the tape is fed
onto the tape roll, and the feeding direction of the tape toward
the push roller is controlled by the feeding direction control
guide and the movement device. This feeding direction of the tape
conforms with the tangential direction of the tape roll at the tape
feeding position, so that the tape is not wound around the push
roller. This can eliminate an adverse effect on the pressing force
of the push roller against the tape roll caused by the tensile
force of the tape per se and variation in the tensile force.
Therefore, shifting of the push roller is restricted, and the tape
can be wound into a roll at high speeds while maintaining a precise
and aligned winding profile.
[0011] In the aforementioned tape winding apparatus, the feeding
direction control guide may have a cylindrical guide surface for
guiding the tape. Further, the push roller may be supported on a
swing arm which is swingable about a central axis of the
cylindrical guide surface of the feeding direction control guide,
and an urging member is further provided to urge the push roller
supported on the swing arm toward the tape roll.
[0012] With this configuration of the tape winding apparatus,
because the swing arm is swingable about the central axis of the
cylindrical guide surface of the feeding direction control guide,
the tensile force acting on the tape that is wound around the
feeding direction control guide does not cause a swinging motion of
the swing arm.
[0013] To be more specific, as in the case of the conventional
system, if the feeding direction control guide (corresponding to
the position control roller disclosed in U.S. Pat. No. 4,778,119)
is supported on a swingable part of the swing arm, the tensile
force acting on the tape that is wound around the feeding direction
control guide will cause the swing arm to swing about its pivot
axis. On the contrary, according to the above configuration of the
present invention, the feeding direction control guide has a
cylindrical guide surface for guiding the tape, and the rotation
axis of the cylindrical guide surface conforms with the pivot axis
of the swing arm. Therefore, a predetermined relative position is
kept between the feeding direction control guide and the swing arm,
and the tensile force of the tape does not cause a swinging motion
of the swing arm.
[0014] In one specific embodiment, the movement device may
comprise: a swing arm supporting the push roller and configured to
be swingable about a central axis of the cylindrical guide surface
of the feeding direction control guide; a slide stage on which the
swing arm is swingably supported while supporting the feeding
direction control guide; a spring configured to apply a pressing
force to the push roller, one end of the spring being engaged with
the swing arm and the other end of the spring being engaged with
the slide stage; a rail along which the slide stage is guided; and
an actuator for moving the slide stage along the rail.
[0015] In another specific embodiment, the movement device may
comprise: a swing arm supporting the push roller and configured to
be swingable about a central axis of the cylindrical guide surface
of the feeding direction control guide; a first longitudinal swing
arm member on which the swing arm is swingably supported; a spring
configured to apply a pressing force to the push roller, one end of
the spring being engaged with the swing arm and the other end of
the spring being engaged with the first longitudinal swing arm
member; and an actuator for swinging the first longitudinal swing
arm member. In this specific embodiment, the tape winding apparatus
may further comprise an optical sensor for sensing an outer
diameter of the tape roll, and a controller configured to receive a
detection signal from the optical sensor, and the controller may
control the actuator so as to swing the first longitudinal swing
arm member in accordance with the detection signal from the optical
sensor.
[0016] In yet another specific embodiment, the feeding direction
control guide may be fixed to a base so as not to be movable
relative to the wind-up core, and the movement device may comprises
a second longitudinal swing arm member supporting the push roller,
and a spring configured to apply a swinging force to the second
longitudinal swing arm member. In this tape winding apparatus, a
pivot axis of the second longitudinal swing arm member is
positioned at a midpoint of a line segment connecting a rotation
axis of the wind-up core and a tape contacting point of the feeding
direction control guide at which point the tape contacts with a
guide surface of the feeding direction control guide for guiding
the tape toward the tape roll.
[0017] According to the present invention, the tape winding
apparatus can wind a tape at high speeds into a roll with a precise
and aligned winding profile because the tensile force of the tape
does not adversely affect on the pressing force of the push
roller.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Other objects and aspects of the present invention will
become more apparent by describing in detail illustrative,
non-limiting embodiments thereof with reference to the accompanying
drawings, in which:
[0019] FIG. 1A shows a structure of a tape winding apparatus
according to a first embodiment of the present invention;
[0020] FIG. 1B is an enlarged view showing a tape feeding position
at which a magnetic tape is fed onto a tape roll;
[0021] FIGS. 2A and 2B explain the operation of the tape winding
apparatus according to the first embodiment, in which FIG. 2A shows
that a small amount of magnetic tape has been wound into a roll,
and FIG. 2B shows that a large amount of magnetic tape has been
wound into a roll;
[0022] FIGS. 3A and 3B show a first modification of the tape
winding apparatus, in which FIG. 3A shows that a small amount of
magnetic tape has been wound into a roll, and FIG. 3B shows that a
large amount of magnetic tape has been wound into a roll;
[0023] FIGS. 4A and 4B show a second modification of the tape
winding apparatus, in which FIG. 4A shows that a small amount of
magnetic tape has been wound into a roll, and FIG. 4B shows that a
large amount of magnetic tape has been wound into a roll; and
[0024] FIG. 5 shows a third modification of the tape winding
apparatus.
DETAILED DESCRIPTION OF THE INVENTION
[0025] With reference to the accompanying drawings, preferred
embodiments of the present invention will be described.
[0026] As seen in FIG. 1A, a tape winding apparatus 1 according to
a first embodiment is shown as a winding mechanism of a
tape-running apparatus provided in a servo writer for recording a
servo signal on a magnetic tape.
[0027] The tape winding apparatus 1 has a base 10 made of a metal
plate or the like, and various devices are arranged on the base 10.
The tape winding apparatus 1 mainly includes a spindle 11, a
feeding-side push roller mechanism 20, an air removal push roller
mechanism 30, optical sensors 41, 42, and a controller 40.
[0028] A wind-up core 12 is attached to the spindle 11. The spindle
11 is driven to rotate by a motor 13 as an example of a rotating
device, so that a magnetic tape MT as an example of a tape is wound
around the wind-up core 12. The rotation of the motor 13 is
controlled by the controller 40.
[0029] The feeding-side push roller mechanism 20 includes a push
roller 21, a feeding direction control guide 22, a swing arm 23, a
slide stage 24, a rail 25, a spring 26, a drive belt member 27, a
motor 28, and an edge control guide 29. The swing arm 23, the slide
stage 24, the rail 25, the drive belt member 27, and the motor 28
constitute a movement device in this embodiment.
[0030] The push roller 21 is a roller made of urethane rubber and
rotatably supported on the swing arm 23. The outer peripheral
surface of the push roller 21 contacts with an outer periphery of a
tape roll TR at a position where the magnetic tape MT is fed onto
the tape roll TR (hereinafter referred to as a "tape feeding
position P"), so that the push roller 21 rolls on the tape roll TR.
Air between the tape roll TR and the magnetic tape MT to be fed
onto the tape roll TR is gradually removed by the pressing force of
the push roller 21. The push roller 21 roughly positions the edges
of the magnetic tape MT to be wound around the tape roll TR.
[0031] It is preferable that the push roller 21 has a hardness of
60 or less (Hs: in compliance with JIS K 6253). In the case where
the push roller 21 is made of urethane rubber, the hardness of 40
or more is preferable in order to prevent the push roller 21 from
adhering to the magnetic tape MT. The hardness of the push roller
21 can be selected such that the lower it is, the more gradually
air between the outermost magnetic tape MT and the tape roll TR
inside this magnetic tape MT is removed, and therefore enabling the
magnetic tape MT to be wound into a roll with a precise and aligned
winding profile.
[0032] Further, the diameter of the push roller 21 is preferably in
the range of 20-30 mm, and most preferably 28 mm. The pressing
force of the push roller 21 against the tape roll TR is preferably
in the range of 2.5-4 N, and most preferably 3 N.
[0033] The feeding direction control guide 22 is a roller for
controlling the feeding direction of the magnetic tape MT that is
fed between the push roller 21 and the tape roll TR. The feeding
direction control guide 22 is a tape guide roller arranged upstream
from the push roller 21 as viewed in a running direction of the
magnetic tape MT. The feeding direction control guide 22 is
positioned most closely to the push roller 21 at the tape feeding
position P. The feeding direction control guide 22 is rotatably
supported on the slide stage 24.
[0034] As seen in FIG. 1B, the controller 40 performs a control
such that the angle .theta. defined by line L1 normal to the line
segment connecting the center O of the tape roll TR and the tape
feeding position P and the magnetic tape MT that is about to be fed
into the tape feeding position P becomes as close to 0 degrees as
possible. This angle .theta. is preferably in the range of -5 to 5
degrees, and more preferably in the range of -5 to 0 degrees. If
this angle .theta. is smaller than 0 degrees, that is, if the
magnetic tape MT is fed into the tape feeding position P so as not
to be wound around the push roller 21, the tensile force of the
magnetic tape MT does not act on the pressing force of the push
roller 21.
[0035] The swing arm 23 is swingably supported on the slide stage
24 such that the pivot axis of the swing arm 23 is coaxial with the
rotation axis of the feeding direction control guide 22. To be more
specific, the pivot axis of the swing arm 23 is coaxial with the
central axis of a cylinder which is defined by a guide surface of
the feeding direction control guide 22 for guiding the magnetic
tape MT. This can ensure that even if the swing arm 23 swings, it
is possible to keep a predetermined relative position between the
guide surface (cylindrical surface) of the feeding direction
control guide 22 and the push roller 21 supported on the swing arm
23.
[0036] The swing arm 23 has one end portion opposite to the push
roller 21, and the feeding direction control guide 22 is positioned
between the push roller 21 and this end portion. A spring
engagement portion 23a is formed in this end portion so that one
end 26a of the spring 26 is hooked in the spring engagement portion
23a. The other end 26b of the spring 26 is hooked in a spring
engagement portion 24a formed in the slide stage 24. Because the
spring 26 functions as a tension spring, the swing arm 23 is urged
in the anticlockwise direction of FIGS. 1A and 1B. Therefore, the
outer peripheral surface of the push roller 21 is pressed against
the outer periphery of the tape roll TR by the action of the spring
26.
[0037] The other end portion of the swing arm 23 is provided with
the push roller 21, and a detection strip 23b extends from the
other end portion in the direction away from the tape roll TR. The
detection strip 23b is a part for blocking light emitted from the
optical sensor 41 to be described later.
[0038] The slide stage 24 supports the feeding direction control
guide 22, the swing arm 23, and the edge control guide 29. The
slide stage 24 is slidable along the rail 25 in the horizontal
direction of FIG. 1A. In other words, the slide stage 24 can slide
along the rail 25 toward and away from the tape roll TR.
[0039] The rail 25 extends in the horizontal direction of FIG. 1A.
The rail 25 guides the slide stage 24 and allows the slide stage 24
to move in parallel with the rail 25.
[0040] The drive belt member 27 constitutes a mechanism for moving
the slide stage 24 in the horizontal direction of FIG. 1A. The
drive belt member 27 includes a belt 27a, a drive pulley 27b, and a
driven pulley 27c. The belt 27a is looped around the drive pulley
27b and the driven pulley 27c which are arranged in the horizontal
direction of FIG. 1A. In other words, the belt 27a extends in the
horizontal direction with a tension being applied to the belt 27a
between the pulleys 27b, 27c, and upper and lower tensed portions
are formed between the pulleys 27b, 27c. The slide stage 24 is
fixed to the belt 27a at the lower tensed portion of the belt
27a.
[0041] A rotary driving force of the motor 28 is input to the drive
pulley 27b. When the motor 28 is driven to rotate and the drive
belt 27 turns, the slide stage 24 moves in the horizontal direction
toward and away from the tape roll TR. A stepping motor or a DC
motor may be employed as the motor 28.
[0042] The edge control guide 29 is a flanged roller. The edge
control guide 29 is rotatably supported on the slide stage 24. The
edge control guide 29 is arranged at a position adjacent to the
outer periphery of the tape roll TR and at a lower side of the
feeding direction control guide 22 as seen in FIG. 1A. To be more
specific, the edge control guide 29 is arranged at a position where
the magnetic tape MT wound around the outermost periphery of the
tape roll TR is ready to enter the tape feeding position P just
before passing through the feeding direction control guide 22.
[0043] The edge control guide 29 guides the tape roll TR such that
only the flange portion thereof comes into contact with the both
side edges of the tape roll TR while the roller portion thereof
does not contact with the outer periphery of the tape roll TR.
Therefore, the flange portion of the edge control guide 29 aligns
the side edges of the magnetic tape MT that is positioned at and
closely to the outer periphery of the tape roll TR without pressing
the tape roll TR.
[0044] The optical sensor 41 has a light emitting portion (not
shown) and a light receiving portion for receiving light emitted
from the light emitting portion. The detection strip 23b enters a
region between the light emitting portion and the light receiving
portion, and the orientation of the swing arm 23 is detected based
on the amount of light blocked by the detection strip 23b. The
detection signal from the optical sensor 41 is output to the
controller 40.
[0045] The air removal push roller mechanism 30 is positioned on
the opposite side of the tape roll TR from the feeding side push
roller mechanism 20. The air removal push roller mechanism 30
includes a push roller 31, a swing arm 33, a slide stage 34, a rail
35, a spring 36, a drive belt member 37, a motor 38, and an edge
control guide 39.
[0046] The push roller 31 is a roller made of urethane rubber that
is the same material as that of the push roller 21, and rotatably
supported on the swing arm 33. The outer peripheral surface of the
push roller 31 contacts with the outer periphery of the tape roll
TR, so that the push roller 31 rolls on the tape roll TR. Air
between the magnetic tape MT positioned at the outermost periphery
of the tape roll TR and the tape roll TR inside the outermost
magnetic tape MT is removed by the pressing force of the push
roller 31, so that the magnetic tape MT can be securely positioned
at the outermost periphery of the tape roll TR.
[0047] The swing arm 33 is swingably supported on the slide stage
34. The swing arm 33 has one end portion opposite to the push
roller 31, and the pivot axis 33c of the swing arm 33 is positioned
between the push roller 31 and this end portion. A spring
engagement portion 33a is formed in this end portion so that one
end 36a of the spring 36 is hooked in the spring engagement portion
33a. The other end 36b of the spring 36 is hooked in a spring
engagement portion 34a formed in the slide stage 34. Because the
spring 36 functions as a tension spring, the swing arm 33 is urged
in the anticlockwise direction of FIG. 1A. Therefore, the outer
peripheral surface of the push roller 31 is pressed against the
outer periphery of the tape roll TR by the action of the spring
36.
[0048] The other end portion of the swing arm 33 is provided with
the push roller 31, and a detection strip 33b extends from the
other end portion in the direction away from the tape roll TR. The
detection strip 33b is a part for blocking light emitted from the
optical sensor 42 to be described later.
[0049] The slide stage 34 supports the swing arm 33 and the edge
control guide 39. The slide stage 34 is slidable along the rail 35
in the horizontal direction of FIG. 1A. In other words, the slide
stage 34 can slide along the rail 35 toward and away from the tape
roll TR.
[0050] The rail 35 extends in the horizontal direction of FIG. 1A.
The rail 35 guides the slide stage 34 and allows the slide stage 34
to move in parallel with the rail 35.
[0051] The drive belt member 37 constitutes a mechanism for moving
the slide stage 34 in the horizontal direction of FIG. 1A. The
drive belt member 37 includes a belt 37a, a drive pulley 37b, and a
driven pulley 37c. The belt 37a is looped around the drive pulley
37b and the driven pulley 37c which are arranged in the horizontal
direction of FIG. 1A. In other words, the belt 37a extends in the
horizontal direction with a tension being applied to the belt 37a
between the pulleys 37b, 37c, and upper and lower tensed portions
are formed between the pulleys 37b, 37c. The slide stage 34 is
fixed to the belt 37a at the upper tensed portion of the belt
37a.
[0052] A rotary driving force of the motor 38 is input to the drive
pulley 37b. When the motor 38 is driven to rotate and the drive
belt 37 turns, the slide stage 34 moves in the horizontal direction
toward and away from the tape roll TR.
[0053] The edge control guide 39 is a flanged roller. The edge
control guide 39 is rotatably supported on the slide stage 34.
Because the function of the edge control guide 39 is the same as
that of the edge control guide 29 as described above, detailed
description of the edge control guide 39 will be omitted.
[0054] The optical sensor 42 has the same function as the optical
sensor 41 as described above. The detection strip 33b enters a
region between the light emitting portion and the light receiving
portion of the optical sensor 42, and the orientation of the swing
arm 33 is detected based on the amount of light blocked by the
detection strip 33b. The detection signal from the optical sensor
42 is output to the controller 40.
[0055] Detection signals (detection results) are input from the
optical sensors 41, 42 to the controller 40. The controller 40
performs a control such that the push roller 21 and the push roller
31 move gradually and radially outward of the tape roll TR in
accordance with a change in the amount of magnetic tape MT wound
around the wind-up core 12. The controller 40 also controls the
rotation speed of a motor for rotating the spindle 11. Further, the
controller 40 inputs a signal for the tensile force of the magnetic
tape MT and a servo signal to be written on the magnetic tape MT to
a servo write head (not shown).
[0056] Description will be focused only to controlling the push
roller 21 and the push roller 31. The controller 40 outputs drive
signals to the motors 28, 38 and controls the motors 28, 38 such
that the input signals from the optical sensors 41, 42 indicate
predetermined constant values. These values are previously stored
in a memory (not shown). For example, as the amount of magnetic
tape MT wound into the tape roll TR increases, the push roller 21
rotates in the clockwise direction, so that the detection strip 23b
blocks more amount of light emitted from the optical sensor 41. In
this instance, the controller 40 causes the drive pulley 27b to
rotate for a certain amount in the anticlockwise direction of FIG.
1A to thereby turn the belt 27a for a certain amount. This causes
the slide stage 24 to move in a direction away from the tape roll
TR. Therefore, the swing arm 23 swings in the anticlockwise
direction to keep a constant orientation.
[0057] The operation of the tape winding apparatus 1 as constructed
above will be described.
[0058] The magnetic tape MT supplied from a tape roll (not shown)
on the magnetic tape feeding side is guided along a plurality of
guide rollers G (one of which is shown in FIG. 1A) and wound into
the tape roll TR on the magnetic tape wind-up side, during which
the servo write head (not shown) records a servo signal on the
magnetic tape MT. As seen in FIG. 1A, the magnetic tape MT runs
along the guide roller G and is wound around the feeding direction
control guide 22 at a downstream from the guide roller G, and then
the tape-running direction of the magnetic tape MT is changed at
the feeding direction control guide 22 to an upward direction of
FIG. 1A so that the magnetic tape MT runs toward the tape feeding
position P. During this time, the magnetic tape MT runs along the
tangential direction of the tape roll TR at the tape feeding
position P. The magnetic tape MT is then wound around the outer
periphery of the tape roll TR at the tape feeding position P.
[0059] At the tape feeding position P the magnetic tape MT is
pressed against the tape roll TR by the push roller 21, so that air
between the tape roll TR and the outermost magnetic tape MT is
removed to a certain extent. The magnetic tape MT that has been
wound into the outermost periphery of the tape roll TR rotates in
the anticlockwise direction of FIG. 1A, and after a 180 degree
rotation of the tape roll TR, both edges of the magnetic tape MT
are aligned with those of the tape roll TR by the flange portion of
the edge control guide 39. The outermost magnetic tape MT having
been aligned with the tape roll TR is pressed against the tape roll
TR by the push roller 31, so that air between the magnetic tape MT
positioned at the outermost periphery of the tape roll TR and the
tape roll TR inside the outermost magnetic tape MT is further
removed and the magnetic tape MT can be more securely and stably
positioned at the outermost periphery of the tape roll TR.
[0060] Further, the outermost magnetic tape MT rotates in the
anticlockwise direction on the tape roll TR by 180 degrees, and at
a position just before the tape feeding position P the both side
edges of the outermost magnetic tape MT are aligned with those of
the tape roll TR by the edge control guide 29. Accordingly, the
magnetic tape MT is wound around the tape roll TR while the width
thereof is aligned with the tape roll TR.
[0061] As the amount of magnetic tape MT wound into the tape roll
TR increases from a small amount as shown in FIG. 2A to a large
amount as shown in FIG. 2B, the push roller 21 moves radially
outward of the tape roll TR, so that the amount of light emitted
from the optical sensor 41 but blocked by the detection strip 23b
changes accordingly. The controller 40 receives a signal for the
amount of received light from the optical sensor 41, and controls
the number of rotations of the motor 28 such that the amount of
received light to be detected by the optical sensor 41 takes a
constant value. Therefore, the push roller 21 moves radially
outward of the tape roll TR while the swing arm 23 keeps the same
orientation.
[0062] Although not shown in FIGS. 2A and 2B, as the push roller 31
moves radially outward of the tape roll TR, the amount of light
emitted from the optical sensor 42 but blocked by the detection
strip 33b changes accordingly. The controller 40 controls the
number of rotations of the motor 38 such that the amount of
received light to be detected by the optical sensor 42 takes a
constant value. Therefore, the push roller 31 moves radially
outward of the tape roll TR while the swing arm 33 keeps the same
orientation.
[0063] During this wind-up process of the magnetic tape MT, as
described above, the magnetic tape MT fed onto the tape roll TR is
pressed against the tape roll TR by the push roller 21 at the tape
feeding position P, so that air between the magnetic tape MT
positioned at the outermost periphery of the tape roll TR and the
tape roll TR inside the outermost magnetic tape MT is removed.
[0064] As described above, because the orientation of the swing arm
23 is constant irrespective of a change in the amount of magnetic
tape MT wound into the tape roll TR, the tape-feeding direction of
the magnetic tape MT running from the feeding direction control
guide 22 to the tape feeding position P substantially and
constantly conforms with the tangential direction of the tape roll
TR at the tape feeding position P.
[0065] According to this embodiment, because the magnetic tape MT
is not wound around the push roller 21, the tensile force of the
magnetic tape MT per se and variation in the tensile force do not
adversely affect on the push roller 21. For this reason, the
pressing force of the push roller 21 applied to the outermost
magnetic tape MT wound around the tape roll TR becomes stable, and
therefore it is possible to wind the magnetic tape MT into a roll
with a precise and aligned winding profile. Further, even if the
wind-up speed for the magnetic tape MT is increased, the tensile
force of the magnetic tape MT per se and variation in the tensile
force do not adversely affect on the push roller 21. Therefore, it
is possible to wind up the magnetic tape MT at high speeds compared
to the conventional magnetic tape wind-up system.
[0066] When comparing FIG. 2A and FIG. 2B, the feeding direction
control guide 22 moves outward in the horizontal direction of FIGS.
2A and 2B from the center point O of the tape roll TR. If the swing
arm 23 keeps the same orientation, the magnetic tape MT running
from the feeding direction control guide 22 to the tape feeding
position P is slightly away from the tangential direction of the
tape roll TR at the tape feeding position P. However, if this shift
amount is very small, the tensile force of the magnetic tape MT
does not substantially affect on the push roller 21 and no problem
occurs.
[0067] In the case where the magnetic tape MT running from the
feeding direction control guide 22 to the tape feeding position P
is necessary to strictly conform with the tangential direction of
the tape roll TR at the tape feeding position P, the outer diameter
of the tape roll TR may be detected with an optical sensor, etc.,
and the movement of the slide stage 24 may be controlled such that
the orientation of the swing arm 23 slightly changes in accordance
with the outer diameter of the tape roll TR. The relation between
outer diameter of the tape roll TR and position of the slide stage
24 can be stored in advance as a table.
[0068] As an alternative, as seen in a modification shown in FIGS.
3A and 3B, the rail 25 and the push roller 21, etc. may be arranged
such that the push roller 21 moves radially outward from the center
point O of the tape roll TR along the diameter of the tape roll TR.
According to this modification, the magnetic tape MT running from
the feeding direction control guide 22 to the tape feeding position
P can strictly conform with the tangential direction of the tape
roll TR at the tape feeding position P while maintaining the
constant orientation of the swing arm 23 as with the tape winding
apparatus 1 shown FIG. 1A.
[0069] Although the present invention has been described in detail
with reference to the above preferred embodiments, the present
invention is not limited to the above specific embodiments and
various changes and modifications may be made without departing
from the scope of the appended claims.
[0070] According to the above embodiments, the push roller 21 is
supported by the slide stage 24 through the swing arm 23, and the
slide stage 24 is moved linearly in one direction. However, the
swing arm 23 for supporting the push roller 21 is not limited to
this specific type. For example, as seen in FIGS. 4A and 4B, the
swing arm 23 may be supported on a longitudinal swing arm member
124 which is also swingable about a pivot axis, and the orientation
of the longitudinal swing arm member 124 may be controlled using an
actuator 128. In this modification, the outer diameter of the tape
roll TR is detected with an optical sensor 141. As seen in FIGS. 4A
and 4B, the actuator 128 is controlled in accordance with the outer
diameter of the tape roll TR such that the line segment OP
(connecting the center O of the tape roll TR and the tape feeding
position P) and the magnetic tape MT running from the feeding
direction control guide 22 to the push roller 21 are always kept at
a right angle irrespective of the outer diameter of the tape roll
TR. Further, if the pivot axis of the swing arm 23 is coaxial with
the central axis of the cylindrical guide surface of the feeding
direction control guide 22, the urging force of the spring 26
applied to the push roller 21 is not subject to the tensile force
of the magnetic tape MT per se and variation in the tensile force.
Therefore, as with the above embodiments, a tape winding apparatus
according to this modification can also wind the magnetic tape MT
into a roll at high speeds while maintaining a precise and aligned
winding profile.
[0071] According to another modification as seen in FIG. 5, a
feeding direction control guide 222 is stationary so as not to be
movable relative to the wind-up core 12. In this modification, the
feeding direction control guide 222 is a non-rotatable fixed guide
pin that is fixed to the base 10. As seen in FIG. 5, if the
diameter of the feeding direction control guide 222 is small, a
tape contacting point at which the magnetic tape MT contacts with
and guided by the guide surface of the feeding direction control
guide 222 may be regarded as being substantially constant. In this
instance, the trajectory of the tape feeding position P in
accordance with a change in the amount of magnetic tape MT wound
into the tape roll TR becomes substantially a circular arc, and the
center point of this circular arc is the midpoint of the line
segment connecting the center point O of the tape roll TR (i.e.,
the rotation axis of the wind-up core 12) and the tape contacting
point. According to this modification, a longitudinal swing arm
member 223 is provided, and the pivot axis for this swing arm
member 223 is positioned to conform with the midpoint of the line
segment. Further, a push roller 221 is supported on one end portion
of the longitudinal swing arm member 223 in such a position to move
along the trajectory of this circular arc. A spring 226 is engaged
with the other end portion of the longitudinal swing arm member
223, so that a swinging force is applied to the swing arm member
223. With this configuration of the tape winding apparatus 1, the
trajectory of the tape feeding position P in accordance with a
change in the amount of magnetic tape MT wound into the tape roll
TR conforms with the trajectory of the push roller 221. Therefore,
the advantageous effects of the present invention as described
above can be obtained with a simple structure.
[0072] In the above preferred embodiments, the tape winding
apparatus 1 used for a servo writer has been described. However, a
tape winding apparatus according to the present invention may be
applicable to other tape winding apparatus such as used for a
magnetic tape drive or used in a wind-up process for adhesive
tape.
[0073] Further, in the first embodiment, the feeding direction
control guide 22 has been described as a roller. However, the
feeding direction control guide is not limited to a roller, and may
have a stationary cylindrical surface such as shown in FIG. 5. As
an alternative, the feeding direction control guide may eject air
so that a tape is guided without contacting with the guide
surface.
EXAMPLE
[0074] Description will be give of an example, in which a tape
winding apparatus according to the present invention was tested to
check for its effectiveness.
[0075] A wind-up test for the magnetic tape was performed using a
servo writer provided with a tape winding apparatus 1 as shown in
FIG. 1A.
[0076] Conditions of the test were as follows.
Thickness of the magnetic tape: 6.6 .mu.m Pressing force of the
push roller: 3 N Diameter of the push roller: 28 mm Material for
the push roller: urethane rubber Hardness of the push roller: 40
(Hs: in compliance with JIS K 6253)
[0077] Under these conditions, the magnetic tape was wound up while
changing the position of the feeding direction control guide such
that the angle .theta. shown in FIG. 1B was defined to be
-10.degree., -5.degree., 0.degree., 5.degree., and 10.degree.,
respectively. The winding profile and the wind-up state of the tape
roll were checked by eye after completing the wind-up operation.
The results of the test were shown in Table 1.
TABLE-US-00001 TABLE 1 Angle .theta. Winding Profile/Wind-up State
-10.degree. Poor -5.degree. Fair 0.degree. Good +5.degree. Fair
+10.degree. Poor
[0078] As far as the results for winding profile and wind-up state
are concerned, the magnetic tape came off from the tape roll due to
hunting of the swing arm when the angle .theta. was +10 degrees.
When the angle .theta. was +5 degrees, the magnetic tape was wound
into a roll. However, the winding profile was not so good. When the
pressing force of the push roller was increased from 3 N to 5N at
the angle .theta. of +5 degrees, the winding profile (i.e.,
variation in the tape edge in the width direction of the magnetic
tape) was improved. However, the magnetic tape was wound up so
tightly that a radial pattern is formed on the tape roll as viewed
from the tape edge direction. Considering all these facts, the test
result was not very good at the test performed at the angle .theta.
of +5 degrees compared with the test result at the angle .theta. of
0 degrees. When the angle .theta. was 0 degrees, the magnetic tape
was wound into a roll with a precise and aligned winding profile.
When the angle .theta. was -5 degrees, the magnetic tape was wound
into a roll. However, the winding profile was slightly inferior
compared with the winding profile at the angle .theta. of 0
degrees. When the angle .theta. was -10 degrees, hunting of the
swing arm did not occur. However, air was not removed sufficiently,
thereby leading to frequent disengagement of the magnetic tape from
the tape roll.
[0079] The magnetic tape could be wound up at high speeds, such as
at 16 m/s, in the range of the angle .theta. from -5 to 5 degrees.
As disclosed in U.S. Pat. No. 4,778,119, the conventional magnetic
tape wind-up system offers the maximum wind-up speed of 10 m/s (600
m/min). Therefore, a tape winding apparatus according to the
present invention can offer a much faster wind-up process.
* * * * *