U.S. patent application number 13/971842 was filed with the patent office on 2013-12-19 for reel.
This patent application is currently assigned to FUJIFILM CORPORATION. The applicant listed for this patent is FUJIFILM CORPORATION. Invention is credited to Kenji TAKENOSHITA.
Application Number | 20130334353 13/971842 |
Document ID | / |
Family ID | 46757562 |
Filed Date | 2013-12-19 |
United States Patent
Application |
20130334353 |
Kind Code |
A1 |
TAKENOSHITA; Kenji |
December 19, 2013 |
REEL
Abstract
The present invention provides a reel which includes: a hub,
around an outer periphery face of which a recording tape is wound;
an annular first flange disposed at one axial direction end portion
of the hub; an annular second flange disposed at the other axial
direction end portion of the hub; a plurality of first pad portions
protruding into the hub from the first flange, the first pad
portions being engaged with the hub to be relatively non-rotatable;
and a plurality of second pad portions protruding into the hub from
the second flange, the plurality of second pad portions being
welded to the plurality of first pad portions.
Inventors: |
TAKENOSHITA; Kenji;
(Odawara-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
FUJIFILM CORPORATION |
Tokyo |
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JP |
|
|
Assignee: |
FUJIFILM CORPORATION
Tokyo
JP
|
Family ID: |
46757562 |
Appl. No.: |
13/971842 |
Filed: |
August 21, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/JP2011/075214 |
Nov 1, 2011 |
|
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13971842 |
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Current U.S.
Class: |
242/118.6 |
Current CPC
Class: |
B65H 75/14 20130101;
G11B 23/037 20130101 |
Class at
Publication: |
242/118.6 |
International
Class: |
B65H 75/14 20060101
B65H075/14 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 28, 2011 |
JP |
2011-042336 |
Claims
1. A reel comprising: a hub, around an outer periphery face of
which a recording tape is wound; an annular first flange disposed
at one axial direction end portion of the hub; an annular second
flange disposed at the other axial direction end portion of the
hub; a plurality of first pad portions protruding into the hub from
the first flange, the first pad portions being engaged with the hub
to be relatively non-rotatable; and a plurality of second pad
portions protruding into the hub from the second flange, the
plurality of second pad portions being welded to the plurality of
first pad portions.
2. The reel according to claim 1, wherein the first pad portions
are engaged with an inner periphery face side of the hub.
3. The reel according to claim 1, further comprising a penetrating
hole formation portion that is integrally formed at an inner
periphery face of the hub and in which penetrating holes are
formed, wherein relative rotation between the first flange and
second flange and the hub is disabled by at least the first pad
portions being fitted into the penetrating holes.
4. The reel according to claim 1, further comprising a circular
plate-shaped reinforcement portion that is integrally formed at an
inner periphery face of the hub so as to be coaxial with the hub,
and in an outer periphery portion of which penetrating holes are
formed, wherein relative rotation between the first flange and
second flange and the hub is disabled by at least the first pad
portions being fitted into the penetrating holes.
5. The reel according to claim 4, wherein a fastening portion for
fastening to a rotary member of a drive device is formed at the
reinforcement portion.
6. The reel according to claim 3, wherein a gap is formed between a
radial direction outer side wall face of the penetrating holes and
a radial direction outer side wall face of at least the first pad
portions.
7. The reel according to claim 3, wherein the first pad portions
are structured in a plurality of different kinds of shape, the
second pad portions are structured in a plurality of kinds of shape
that correspond with the first pad portions, and the penetrating
holes are formed in a plurality of kinds of shape that correspond
with at least the first pad portions.
8. The reel according to claim 1, wherein the first flange at which
the first pad portions are provided and the second flange at which
the second pad portions are provided are formed in the same
shape.
9. The reel according to claim 7, wherein each of the first pad
portions and the second pad portions includes an identical
flat-shaped plate.
10. The reel according to claim 9, wherein energy directors are
provided with a welding surface of each of the first pad portions
and the second pad portions, and the energy directors are provided
intermittently in a circumferential direction and are spaced by a
predetermined interval in a radial direction.
11. The reel according to claim 9, wherein energy directors are
provided from an end portion substantially to a middle portion in a
circumferential direction with a welding surface of each of the
first pad portions and the second pad portions, such that when the
welding surfaces of the first pad portions are superposed with the
welding surfaces of the second pad portion, the energy directors of
the first pad portions do not face with the energy directors of the
second pad portions.
12. The reel according to claim 9, wherein the penetrating holes
are formed with shapes the same as the first pad portions and the
second pad portions, and a plate thickness of the penetrating hole
formation portion is twice plate thicknesses of the first pad
portions and the second pad portions.
13. The reel according to claim 7, wherein each of the first pad
portions and the second pad portions includes first welding ribs
that is formed with a longer and narrow shape and second welding
ribs that is formed with a shorter and narrow shape, and the first
welding ribs and the second welding ribs are provided alternating
at equal intervals.
14. The reel according to claim 13, wherein first energy directors
are formed at a radial direction outer side on the first welding
ribs, and second energy directors are formed at a radial direction
inner side on the second welding ribs.
15. The reel according to claim 13, wherein the first welding ribs
and the second welding ribs protrude to the same heights, and a
plate thickness of the penetrating hole formation portion is twice
protrusion height of the first welding ribs and second welding
ribs.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation application of
International Application No. PCT/JP2011/075214, filed Nov. 1,
2011, the disclosure of which is incorporated herein by reference
in its entirety. Further, this application claims priority from
Japanese Patent Application No. 2011-042336, filed Feb. 28, 2011,
the disclosure of which is incorporated herein by reference in its
entirety.
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates to a reel on which a recording
tape such as a magnetic tape or the like is wound.
[0004] 2. Related Art
[0005] Heretofore, a recording tape cartridge has been known in
which a recording tape such as a magnetic tape or the like, which
is principally used as an information recording and replaying
medium for computers and the like (data backup), is wound on a
reel, and the reel is singly accommodated in a case.
[0006] A reel with a three-piece structure is known as a reel to be
accommodated in this recording tape cartridge. In the three-piece
structure, an upper circular tube portion is formed at an inner
periphery portion of an upper flange, a lower circular tube portion
is formed at an inner periphery portion of a lower flange, the
upper circular tube portion and lower circular tube portion are
welded together, and a hub is sheathed around the outer periphery
face side of the upper circular tube portion and lower circular
tube portion (for example, see Japanese Patent Application
Laid-Open (JP-A) No. 2007-299437).
[0007] However, in the reel disclosed in Japanese Patent
Application Laid-Open (JP-A) No. 2007-299437, the upper circular
tube portion and lower circular tube portion are welded along the
whole periphery thereof. Therefore, process efficiency in a welding
process cannot necessarily be considered to be excellent. In
addition, a turning preventer that prevents the hub from rotating
relative to the upper and lower flanges must be separately
formed.
SUMMARY
[0008] The present invention provides a reel that may improve
process efficiency in a welding process.
[0009] A reel according to a first aspect of the present invention
includes: a hub, around an outer periphery face of which a
recording tape is wound; an annular first flange disposed at one
axial direction end portion of the hub; an annular second flange
disposed at the other axial direction end portion of the hub;
plural first pad portions protruding into the hub from the first
flange, the first pad portions being engaged with the hub to be
relatively non-rotatable; and plural second pad portions protruding
into the hub from the second flange, the plural second pad portions
being welded to the plural first pad portions.
[0010] According to a reel in accordance with the first aspect,
because the reel is assembled by the plural first pad portions
protruding into the hub interior from the first flange being welded
to the plural second pad portions protruding into the hub interior
from the second flange, process efficiency in a welding process may
be improved. Moreover, because the first flange and the second
flange may be made incapable of rotating relative to the hub by the
first pad portions being engaged with the hub to disable relative
rotation, there is no need to form a separate turning
preventer.
[0011] In a reel according to a second aspect of the present
invention, in the reel according to the first aspect, the first pad
portions are engaged with an inner periphery face side of the
hub.
[0012] According to a reel in accordance with the second aspect,
the first pad portions and second pad portions may be welded at the
inner periphery face side of the hub. Therefore, the first flange
and second flange may be welded more securely than in a structure
in which first pad portions and second pad portions are welded at
the center side of a hub. The meaning of the term "inner periphery
face side of the hub" as used herein is not limited to positions
adjacent to the inner periphery face of the hub but includes
positions that are a little toward the radial direction inner side
from the inner periphery face of the hub.
[0013] In a reel according to a third aspect of the present
invention, the reel according to the first aspect further includes
a penetrating hole formation portion that is integrally formed at
an inner periphery face of the hub and in which penetrating holes
are formed, wherein relative rotation between the first flange and
second flange and the hub is disabled by at least the first pad
portions being fitted into the penetrating holes.
[0014] According to a reel in accordance with the third aspect, the
first pad portions and second pad portions may be welded with ease.
Moreover, relative rotation between the first flange and second
flange and the hub may be disabled with a simple structure.
[0015] In a reel according to a fourth aspect of the present
invention, the reel according to the first aspect further includes
a circular plate-shaped reinforcement portion that is integrally
formed at an inner periphery face of the hub so as to be coaxial
with the hub, and in an outer periphery portion of which
penetrating holes are formed, wherein relative rotation between the
first flange and second flange and the hub is disabled by at least
the first pad portions being fitted into the penetrating holes.
[0016] According to a reel in accordance with the fourth aspect,
the first pad portions and second pad portions may be welded with
ease. Moreover, relative rotation between the first flange and
second flange and the hub may be disabled with a simple structure.
Further, a hub with a higher stiffness (strength) than a hub that
does not include a reinforcement portion can be provided.
[0017] In a reel according to a fifth aspect of the present
invention, in the reel according to the fourth aspect, a fastening
portion for fastening to a rotary member of a drive device is
formed at the reinforcement portion.
[0018] According to a reel in accordance with the fifth aspect, the
reel may be directly installed in a drive device.
[0019] In a reel according to a sixth aspect of the present
invention, in the reel according to the third aspect, a gap is
formed between a radial direction outer side wall face of the
penetrating holes and a radial direction outer side wall face of at
least the first pad portions.
[0020] According to a reel in accordance with the sixth aspect,
because gaps are formed between the radial direction outer side
wall faces of the penetrating holes and the radial direction outer
side wall faces of the at least the first pad portions, when a
recording tape is wound on the hub, a deformation of the hub caused
by winding force of the recording tape may be absorbed by the
gaps.
[0021] In a reel according to a seventh aspect of the present
invention, in the reel according to the third aspect, the first pad
portions are structured in plural different kinds of shape, the
second pad portions are structured in plural kinds of shape that
correspond with the first pad portions, and the penetrating holes
are formed in plural kinds of shape that correspond with at least
the first pad portions.
[0022] According to a reel in accordance with the seventh aspect, a
combination in which the first pad portions of the first flange are
welded to the second pad portions of the second flange is
specifically determined in the circumferential direction. In
particular, if the first pad portions and the second pad portions
are respectively formed in corresponding shapes with equal
spacings, the first pad portions and second pad portions are
unlikely to become slanted. Thus, surface runout of the first
flange and the second flange may be suppressed or prevented.
[0023] In a reel according to an eighth aspect of the present
invention, in the reel according to the first aspect, the first
flange at which the first pad portions are provided and the second
flange at which the second pad portions are provided are formed in
the same shape.
[0024] According to a reel in accordance with the eighth aspect,
the first flange and the second flange may be formed by a single
mold. Hence, fabrication costs may be reduced.
[0025] In a reel according to a ninth aspect of the present
invention, in the reel according to the seventh aspect, each of the
first pad portions and the second pad portions includes an
identical flat-shaped plate.
[0026] According to a reel in accordance with the ninth aspect, the
first pad portions and second pad portions may be formed with ease.
Hence, fabrication costs may be reduced.
[0027] In a reel according to a tenth aspect of the present
invention, in the reel according to the ninth aspect, energy
directors are provided with a welding surface of each of the first
pad portions and the second pad portions, and the energy directors
are provided intermittently in a circumferential direction and are
spaced by a predetermined interval in a radial direction.
[0028] According to a reel in accordance with the tenth aspect,
welding areas are increased and the energy of ultrasonic
oscillations for melting the energy directors, may be efficiently
transmitted to the energy directors.
[0029] In a reel according to a eleventh aspect of the present
invention, in the reel according to the ninth aspect, energy
directors are provided from an end portion substantially to a
middle portion in a circumferential direction with a welding
surface of each of the first pad portions and the second pad
portions, such that when the welding surfaces of the first pad
portions are superposed with the welding surfaces of the second pad
portion, the energy directors of the first pad portions do not face
with the energy directors of the second pad portions.
[0030] According to a reel in accordance with the eleventh aspect,
welding areas are increased and the energy of ultrasonic
oscillations for melting the energy directors, may be efficiently
transmitted to the energy directors. Further, the shapes of the
energy directors formed on the first pad portion and the second pad
portions may be simplified.
[0031] In a reel according to a twelfth aspect of the present
invention, in the reel according to the ninth aspect, the
penetrating holes are formed with shapes the same as the first pad
portions and the second pad portions, and a plate thickness of the
penetrating hole formation portion is twice plate thicknesses of
the first pad portions and the second pad portions.
[0032] According to a reel in accordance with the twelfth aspect,
the penetrating holes may be formed with ease. Hence, fabrication
costs may be reduced.
[0033] In a reel according to a thirteenth aspect of the present
invention, in the reel according to the seventh aspect, each of the
first pad portions and the second pad portions includes first
welding ribs that is formed with a longer and narrow shape and
second welding ribs that is formed with a shorter and narrow shape,
and the first welding ribs and the second welding ribs are provided
alternating at equal intervals.
[0034] According to a reel in accordance with the thirteenth
aspect, the first pad portions and second pad portions may be
formed with ease. Hence, fabrication costs may be reduced.
[0035] In a reel according to a fourteenth aspect of the present
invention, in the reel according to the thirteenth aspect, first
energy directors are formed at a radial direction outer side on the
first welding ribs, and second energy directors are formed at a
radial direction inner side on the second welding ribs.
[0036] According to a reel in accordance with the fourteenth
aspect, welding areas are increased and the energy of ultrasonic
oscillations for melting the energy directors, may be efficiently
transmitted to the energy directors.
[0037] In a reel according to a fifteenth aspect of the present
invention, in the reel according to the thirteenth aspect, the
first welding ribs and the second welding ribs protrude to the same
heights, and a plate thickness of the penetrating hole formation
portion is twice protrusion height of the first welding ribs and
second welding ribs.
[0038] According to a reel in accordance with the fifteenth aspect,
the first welding ribs and the second welding ribs are unlikely to
cause slanting in the radial direction. Thus, surface runout of the
first flange and the second flange may be suppressed or
prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Exemplary embodiments of the present invention will be
described in detail based on the following figures, wherein:
[0040] FIG. 1 is a perspective diagram showing a pair of reels
installed in a drive device.
[0041] FIG. 2 is an exploded perspective diagram of a reel in
accordance with a first exemplary embodiment.
[0042] FIG. 3 is an exploded perspective sectional diagram in which
principal portions of the reel in accordance with the first
exemplary embodiment are shown magnified.
[0043] FIG. 4 is a sectional perspective diagram of the reel in
accordance with the first exemplary embodiment.
[0044] FIG. 5 is a sectional diagram in which principal portions of
the reel in accordance with the first exemplary embodiment are
shown magnified.
[0045] FIG. 6A is a perspective diagram showing an example of the
shapes of energy directors formed at protrusion portions of the
reel in accordance with the first exemplary embodiment.
[0046] FIG. 6B is a perspective diagram showing another example of
the shapes of the energy directors formed at the protrusion portion
of the reel in accordance with the first exemplary embodiment.
[0047] FIG. 7 is an exploded perspective diagram of a reel in
accordance with a second exemplary embodiment.
[0048] FIG. 8 is a plan diagram showing welding ribs that are
formed at protrusion portions of the reel in accordance with the
second exemplary embodiment.
[0049] FIG. 9 is a perspective diagram showing a reel hub of the
reel in accordance with the second exemplary embodiment viewed from
beneath.
[0050] FIG. 10 is a sectional diagram showing a state in which the
welding ribs formed at the protrusion portions of the reel in
accordance with the second exemplary embodiment are mutually
welded.
[0051] FIG. 11 is a sectional diagram in which principal portions
of the reel in accordance with the second exemplary embodiment are
shown magnified.
DETAILED DESCRIPTION
[0052] Herebelow, exemplary embodiments relating to the present
invention are described in detail in accordance with the drawings.
For convenience in the descriptions, the arrow UP in FIG. 1
represents an upward direction, the arrow DO represents a downward
direction, and a rotation axis direction of reels 10 and 20
according to the present exemplary embodiments is referred to as an
up-and-down direction (or height direction). Firstly, a first
exemplary embodiment is described.
[0053] The reels 10 and 20 according to the present exemplary
embodiment are fabricated of a synthetic resin such as, for
example, polycarbonate (PC). As shown in FIG. 1, the reels 10 and
20 are provided as a pair inside a casing 52 of a drive device 50
(of which only a floor plate 54 and three support pillars 56 are
shown in FIG. 1).
[0054] The reel 10 is used for feeding out a recording tape T and
the reel 20 is used for taking up the recording tape T. While the
recording tape T is being fed out from the reel 10 and taken up at
the reel 20, the recording tape T slides against a recording/replay
head 60. Thus, data is recorded on the recording tape T by the
recording/replay head 60 and/or data that has been recorded at the
recording tape T is replayed.
[0055] A plural number (four in the drawing, in sets of two) of
tape guides 58 are rotatably provided on the floor plate 54 at the
two sides of the recording/replay head 60. The recording tape T
being unwound from the reel 10 and taken up at the reel 20 is
guided by the tape guides 58.
[0056] The reels 10 and 20 are structured with reel hubs 12 and 22,
upper flanges 14 and 24, lower flanges 16 and 26, and reinforcement
portions 18 and 28 (see FIG. 2 to FIG. 5). The reel hubs 12 and 22
structure axial central portions of the reels 10 and 20 and have
substantially circular tube shapes. The upper flanges 14 and 24
have annular shapes and serve as first flanges provided at upper
end portion sides of the reel hubs 12 and 22. The lower flanges 16
and 26 have annular shapes and serve as second flanges provided at
lower end portion sides of the reel hubs 12 and 22. The
reinforcement portions 18 and 28 have substantially circular plate
shapes that serve as penetrating hole formation portions, which are
integrally continuous with height (axial) direction middle portions
of inner periphery faces of the reel hubs 12 and 22.
[0057] The recording tape T, which is a magnetic tape or the like
and serves as an information recording and replaying medium, is
wound around the outer periphery face of the reel hub 12 of the
reel 10. Width direction end portions of the recording tape T are
retained by the upper flange 14 and the lower flange 16. The
recording tape T that has been fed out from the reel 10 is taken up
onto the outer periphery face of the reel hub 22 of the reel 20,
and the width direction end portions thereof are retained by the
upper flange 24 and the lower flange 26.
[0058] The meaning of the term "substantially circular tube shape"
as used in the present exemplary embodiments includes generally
circular rod shapes in which the shapes of the outer periphery
faces (winding faces) of the reel hubs 12 and 22 on which the
recording tape T is wound are formed as bulging cylinder shapes or
the like, hollow shapes that are not purely circular tube shapes,
in which ribs or the like are provided protruding from the inner
periphery face sides of the reel hubs 12 and 22, and so forth.
[0059] A motor that serves as a drive source (not shown in the
drawings) is provided at the drive device 50. A pair of rotary
members (not shown in the drawings) transmit rotary driving force
from a rotary shaft of the motor (not shown in the drawings). The
respective rotary members are rotatably provided in a pair of
aperture portions (not shown in the drawings) that are formed in
the casing 52 (the floor plate 54) of the drive device 50. The
reinforcement portions 18 and 28 of the reels 10 and 20 are
integrally fixed (fastened) to the respective rotary members by
unillustrated screws.
[0060] The structures of the reel 10 and the reel 20 are identical.
Accordingly, the reel 10 is taken as an example and described
below. As shown in FIG. 2 to FIG. 5, an upper circular tube portion
15 is integrally formed at an inner periphery edge portion of the
upper flange 14 of the reel 10. The upper circular tube portion 15
extends downward by a predetermined height, to be inserted into the
reel hub 12. A lower circular tube portion 17 is integrally formed
at an inner periphery edge portion of the lower flange 16. The
lower circular tube portion 17 extends upward by a predetermined
height, to be inserted into the reel hub 12.
[0061] A plural number (for example, six) of protrusion portions 32
with flat plate shapes, which serve as first pad portions, are
integrally formed at equal intervals at a lower end portion of the
upper circular tube portion 15. The protrusion portions 32 protrude
to the radial direction inner side (toward a rotation center
portion of the reel 10). Similarly, a plural number (the same as
that of the protrusion portions 32, which is six in this case) of
protrusion portions 34 with flat plate shapes, which serve as
second pad portions, are integrally formed at equal intervals at an
upper end portion of the lower circular tube portion 17. The
protrusion portions 34 protrude to the radial direction inner side
(toward the rotation center portion of the reel 10).
[0062] The protrusion portions 32 and the protrusion portions 34
have identical shapes, and the height of the upper circular tube
portion 15 and the height of the lower circular tube portion 17 are
the same. That is, the upper flange 14 and the lower flange 16 are
formed in identical shapes. Therefore, the upper flange 14 and the
lower flange 16 are structures that may be formed by a single mold,
and that may reduce fabrication costs.
[0063] The height of the upper circular tube portion 15 and the
height of the lower circular tube portion 17 with respect to the
reel hub 12 are set to heights such that, when the reel hub 12 is
sheathed around the outer periphery face sides of the upper
circular tube portion 15 and the lower circular tube portion 17, no
gap is formed between an upper end face of the reel hub 12 and a
lower face of the upper flange 14 or between a lower end face of
the reel hub 12 and an upper face of the lower flange 16, as shown
in FIG. 5. Therefore, deformation of the upper flange 14 and the
lower flange 16 by winding force of the recording tape T can be
suppressed.
[0064] As shown in FIG. 2 to FIG. 4, a plural number (the same as
that of the protrusion portions 32 and 34, which is six in this
case) of penetrating holes 30 are formed in the reinforcement
portion 18 of the reel hub 12 at an outer periphery edge portion
side thereof (positions adjacent to the inner periphery face of the
reel hub 12). The penetrating holes 30 are formed at equal
intervals, with shapes the same as the protrusion portions 32 and
34. A plate thickness of the region of the reinforcement portion 18
in which the penetrating holes 30 are formed is twice the plate
thicknesses of the protrusion portions 32 and 34 (see FIG. 5).
[0065] In this structure, as shown in FIG. 4 and FIG. 5, the
protrusion portions 32 of the upper flange 14 are fitted into the
penetrating holes 30 formed in the reinforcement portion 18 from
above, and the protrusion portions 34 of the lower flange 16 are
fitted into the penetrating holes 30 from below. Thus, the reel hub
12 is made non-rotatable relative to the upper flange 14 and the
lower flange 16 (rotating (turning) is prevented). By the
protrusion portions 32 and protrusion portions 34 being
ultrasonically welded, the upper flange 14 and the lower flange 16
are joined together and the reel hub 12 is integrally mounted at
the outer periphery face side of the upper circular tube portion 15
and the lower circular tube portion 17.
[0066] As shown in FIG. 6A, two rows of energy directors
(hereinafter referred to as EDs 37) that serve as welding fluxes
are provided protruding from a welding surface of each of the
protrusion portions 32 and 34. The EDs 37 of each protrusion
portion 32 or 34 are provided intermittently in the circumferential
direction (at equal intervals) and are spaced by a predetermined
interval in the radial direction. Accordingly, welding areas are
increased and the energy of ultrasonic oscillations for melting the
EDs 37 may be efficiently transmitted to the EDs 37.
[0067] As shown in FIG. 6B, the EDs 37 may be provided from an end
portion substantially to a middle portion in the circumferential
direction (i.e., on substantially half) of the welding surface of
each protrusion portion 32 or 34. Thus, it may be that when the
welding surfaces of the protrusion portions 32 are superposed with
the welding surfaces of the protrusion portions 34, the EDs 37 of
the protrusion portions 32 do not face (overlap) with the EDs 37 of
the protrusion portions 34.
[0068] That is, it may be that the EDs 37 formed substantially at a
circumferential direction half of the welding surface of one
protrusion portion 32 or 34 face the welding surface of another
protrusion portion 32 or 34 from the other end portion
substantially to the middle portion of the other welding surface
(i.e., substantially the other half at which the EDs 37 thereof are
not formed). Accordingly, the shapes of the EDs 37 formed on the
protrusion portions 32 and 34 may be simplified.
[0069] As shown in FIG. 2 to FIG. 4, three screw hole portions 36
that serve as a fastening portion are formed at equal intervals on
a concentric circumference of the reinforcement portion 18. Screws
for fastening to the rotary member of the drive device 50 are
inserted through the screw hole portions 36. A protrusion portion
38 is integrally formed at a lower face side of each screw hole
portion 36. The protrusion portion 38 protrudes downward in a
circular tube shape that is coaxial with the screw hole portion 36
(and communicates with the screw hole portion 36). With this
structure, positioning of the reel 10 (the reinforcement portion
18) in the up-and-down (height) direction with respect to the
rotary member is implemented by the protrusion portions 38 abutting
against an upper face of the rotary member.
[0070] A circular hole portion 40 is formed in the rotation center
portion of the reinforcement portion 18. An output shaft portion
(not shown in the drawings) protruding from the rotary member of
the drive device 50 is inserted (fitted) into the circular hole
portion 40. Thus, with this structure, positioning of the reel 10
(the reinforcement portion 18) in the radial direction with respect
to the rotary member (i.e., centering) is implemented.
[0071] A plural number (for example, three) of protruding portions
(not shown in the drawings) are protrudingly provided at equal
intervals on a concentric circumference of the rotary member. A
plural number of recessed portions 42 (the same number as that of
the protruding portions, which is three in this case) are formed at
equal intervals on a concentric circumference in the lower face of
the reinforcement portion 18, at the radial direction inner side
relative to the screw hole portions 36 (a region at which the plate
thickness is large). The protruding portions fit into the recessed
portions 42. Thus, with this structure, positioning of the reel 10
(the reinforcement portion 18) with respect to the rotary member in
the circumferential direction is implemented, and the screw hole
portions 36 may be matched up with screw boss portions (not shown
in the drawings) formed at the rotary member.
[0072] Now, operation of the reel 10 with the structure described
above is described. As mentioned above, the reel 10 is fabricated
by the plural (the same number as the penetrating holes 30)
protrusion portions 32 of the upper flange 14 and the plural (the
same number as the penetrating holes 30) protrusion portions 34 of
the lower flange 16 being fitted into the plural penetrating holes
30 formed in the reinforcement portion 18, and the protrusion
portions 32 and protrusion portions 34 being joined together by
ultrasonic welding.
[0073] That is, in a welding process for fabrication of the reel
10, it is sufficient for just the protrusion portions 32 and
protrusion portions 34 to be ultrasonically welded. Therefore,
compared to a structure in which the lower end face of the upper
circular tube portion 15 and the upper end face of the lower
circular tube portion 17 are ultrasonically welded over the whole
periphery, process efficiency may be improved (a process time
required for the welding may be shortened). Moreover, because the
protrusion portions 32 and 34 are welded at the inner periphery
face side of the reel hub 12, the upper flange 14 and lower flange
16 may be more securely welded than in a structure in which the
protrusion portions 32 and 34 are welded at the reel hub 12 center
side.
[0074] Furthermore, by the ultrasonic welding of the protrusion
portions 32 of the upper flange 14 and the protrusion portions 34
of the lower flange 16 that are fitted into the penetrating holes
30 formed in the reinforcement portion 18 of the reel hub 12, the
upper flange 14 and lower flange 16 may be joined together and may
be mounted to make the reel hub 12 non-rotatable with respect to
the upper flange 14 and lower flange 16.
[0075] Therefore, there is no need to separately form a turning
preventer to make the reel hub 12 and the upper and lower flanges
14 and 16 relatively non-rotatable. Thus, compared to a structure
in which a turning preventer for making the reel hub 12 and the
upper and lower flanges 14 and 16 relatively non-rotatable is
separately formed, fabrication of molds for molding the parts may
be simplified and mold fabrication costs may be reduced.
[0076] Moreover, because the upper flange 14 and the lower flange
16 have the same shape (symmetry between the upper and the lower),
a single mold is sufficient for fabricating the upper flange 14 and
the lower flange 16. Thus, compared to a structure in which the
shapes of the upper flange 14 and the lower flange 16 are different
and a mold for the upper flange 14 and a mold for the lower flange
16 are separately required, fabrication costs may be further
reduced.
[0077] The protrusion portions 32 that are plurally (in the same
number as the penetrating holes 30) formed at equal intervals on
the upper flange 14 and the protrusion portions 34 that are
plurally (in the same number as the penetrating holes 30) formed at
equal intervals on the lower flange 16 are fitted into the
penetrating holes 30 that are plurally formed at equal intervals in
the reinforcement portion 18 of the reel hub 12. Thus, looseness
(and axial misalignment) between the reel hub 12 and the upper and
lower flanges 14 and 16 may be suppressed or prevented.
[0078] The fastening portion (the screw hole portions 36) for
fastening to the drive device (rotary member) is provided at the
reinforcement portion 18 that is formed integrally with the reel
hub 12 around which the magnetic tape T is wound. Therefore,
compared to a structure in which a portion for fastening to a drive
device is a separate body from the reel hub 12, stiffness
(strength) of the reel hub 12 may be assured and running stability
of the magnetic tape T may be improved.
[0079] The reel 20 is the same. The reels 10 and 20 are mounted and
fixed to the Os of the drive device 50 with screws. That is, screws
are inserted through the screw hole portions 36 of the
reinforcement portions 18 and 28 of the reels 10 and 20 and
threaded into the screw boss portions of the rotary members, and
thus the reinforcement portions 18 and 28 of the reels 10 and 20
are fastened to the rotary members. Thus, the reels 10 and 20 may
be directly installed in the drive device 50.
[0080] Next, a second exemplary embodiment is described. Portions
that are the same as in the above-described first exemplary
embodiment are assigned the same reference numerals and are not
described in detail (nor operations thereof). The second exemplary
embodiment too is described using the reel 10 as an example, and
the reel 20 is again the same.
[0081] As shown in FIG. 7 to FIG. 11, in the upper flange 14 and
the lower flange 16 of the reel 10 according to the second
exemplary embodiment, protrusion portions 33 and 35 are integrally
formed to protrude from the lower end portion of the upper circular
tube portion 15 and the upper end portion of the lower circular
tube portion 17. Each of the protrusion portions 33 and 35
protrudes in an annular shape to the radial direction inner
side.
[0082] As shown in more detail in FIG. 8, long, narrow first
welding ribs 46 and shorter, narrow second welding ribs 48 are
provided protruding from a welding surface (lower face) of the
protrusion portion 33 of the upper flange 14 (i.e., the upper
circular tube portion 15) in plural numbers alternating at equal
intervals (in the illustrated case, three of each at 120.degree.
intervals, making a total of six ribs). The first welding ribs 46
and second welding ribs 48 serve as the first pad portions.
[0083] Similarly, the long, narrow first welding ribs 46 and
shorter, narrow second welding ribs 48 are provided protruding from
a welding surface (upper face) of the protrusion portion 35 of the
lower flange 16 (i.e., the lower circular tube portion 17) in
plural numbers alternating at equal intervals (in the illustrated
case, three of each at 120.degree. intervals, making a total of six
ribs). These first welding ribs 46 and second welding ribs 48 serve
as the second pad portions. Respective single rows of the EDs 37
are formed at the first welding ribs 46 and the second welding ribs
48, at the radial direction outer side on the first welding ribs 46
and at the radial direction inner side on the second welding ribs
48.
[0084] As illustrated in detail in FIG. 9 and FIG. 10, the
penetrating holes 30 in the reinforcement portion 18 of the reel 10
according to the second exemplary embodiment are formed at
positions set a little toward the radial direction inner side from
the inner periphery face of the reel hub 12, and are structured
such that the first welding ribs 46 and second welding ribs 48 can
be respectively fitted therein.
[0085] Thus, the upper flange 14 and the lower flange 16 are joined
together by the first welding ribs 46 of the protrusion portion 33
being welded to the second welding ribs 48 of the protrusion
portion 35 and the second welding ribs 48 of the protrusion portion
33 being welded to the first welding ribs 46 of the protrusion
portion 35.
[0086] Accordingly, step portions 44 are formed at each penetrating
hole 30, alternating between the upper face side and the lower face
side of the reinforcement portion 18. The step portions 44 are
formed at both of circumferential direction end edge portions of
each penetrating hole 30. The step portions 44 are for making up
differences in length in the circumferential direction between the
first welding ribs 46 and the second welding ribs 48 (allowing for
the two circumferential direction end edge portions of each first
welding rib 46 being longer in the circumferential direction than
the second welding rib 48).
[0087] That is, the first welding ribs 46 and the second welding
ribs 48 protrude to the same heights, and the plate thickness of
the reinforcement portion 18 at the region in which the penetrating
holes 30 are formed is twice the protrusion height of the first
welding ribs 46 and second welding ribs 48. The height of each step
portion 44 is the same as the protrusion height of the first
welding rib 46 (which is half of the plate thickness of the
reinforcement portion 18 at the region in which the penetrating
holes 30 are formed).
[0088] Thus, in this structure, as shown in FIG. 10, the first
welding ribs 46 that are fitted into the penetrating holes 30 and
the second welding ribs 48 that are fitted into the penetrating
holes 30 may be welded by the respective EDs 37 that have
positional relationships so as not to face one another in the
up-and-down direction (to be offset from one another in the radial
direction and not overlap).
[0089] Thus, with the structure in which the first welding ribs 46
at which the EDs 37 are formed at the radial direction outer side
and the second welding ribs 48 at which the EDs 37 are formed at
the radial direction inner side are superposed and joined (the
structure in which the EDs 37 do not overlap with one another), the
first welding ribs 46 and the second welding ribs 48 are unlikely
to cause slanting in the radial direction. Thus, surface runout of
the upper flange 14 and the lower flange 16 may be suppressed or
prevented.
[0090] As shown in FIG. 11, a gap S1 in the radial direction is
formed between each of wall faces 18A at the radial direction outer
sides of the penetrating holes 30 and each of wall faces 46A and
48A at the radial direction outer sides of the first welding ribs
46 and second welding ribs 48 fitted into the penetrating holes 30.
A gap S2 in the radial direction is also formed between an inner
periphery face 12A of the reel hub 12 and outer periphery faces 15A
and 17A of the upper circular tube portion 15 and the lower
circular tube portion 17.
[0091] At the inner periphery face side of the reel hub 12, the
substantially circular plate-shaped reinforcement portion 18 that
is concentric with the reel hub 12 is integrally provided to be
continuous. Therefore, the radial direction stiffness (strength) of
the reel hub 12 is improved compared to a reel hub in which the
reinforcement portion 18 is not integrally provided to be
continuous (not shown in the drawings). Consequently, deformation
of the reel hub 12 by winding force of the recording tape T may be
suppressed, and effects on the upper flange 14 and the lower flange
16 may be prevented.
[0092] At the same time, because the above-mentioned gaps S1 and S2
are formed in the radial direction, deformation of the reel hub 12
by the winding force of the recording tape T may be absorbed by
these gaps S1 and S2. Therefore, effects on the upper flange 14 and
the lower flange 16 may be further prevented. Herein, the gaps S1
and S2 are set at, for example, between 0.05 mm and 0.5 mm.
[0093] Hereabove, the reels 10 and 20 according to the present
exemplary embodiments are described on the basis of the attached
drawings, but the reels 10 and 20 according to the present
exemplary embodiments are not limited to the reels shown in the
drawings; designs may be modified as appropriate within a scope not
departing from the spirit of the present invention. For example,
the structures in which both the first pad portions (the protrusion
portions 32 or the first welding ribs 46 and second welding ribs
48) and the second pad portions (the protrusion portions 34 or the
first welding ribs 46 and second welding ribs 48) are together
fitted into the penetrating holes 30 in the reinforcement portion
18 or 28 are not limiting; structures in which one or both of the
first pad portions and the second pad portions are fitted in are
possible.
[0094] However, in a structure in which both the first pad portions
and the second pad portions are together fitted into the
penetrating holes 30 of the reinforcement portion 18 or 28, the
upper flange 14 at which the first pad portions are provided and
the lower flange 16 at which the second pad portions are provided
may be formed in the same shape, which is desirable. Further, in
the illustrated case the upper flange 14 and lower flange 16 are
joined together by the welding ribs 46 and 48 of two kinds with
different shapes, but the upper flange 14 and lower flange 16 may
be joined together by welding ribs of three or more kinds with
different shapes.
[0095] In this case it is desirable for the welding ribs with
different shapes to be formed alternatingly at equal intervals.
Thus, surface runout of the upper flange 14 and the lower flange 16
may be suppressed or prevented. Further, the protrusion portions 38
are not limited to being formed at the lower faces of the screw
hole portions 36 coaxially with the screw hole portions 36, and may
be formed at the lower face of the reinforcement portion 18 or 28
on a different concentric circumference from the screw hole
portions 36.
[0096] The recessed portions 42 may be formed in the rotary member
and the protruding portions formed at the reinforcement portion 18
or 28 to implement positioning in the circumferential direction
(matching up the positions of the screw hole portions 36 at the
reinforcement position 18 or 28 with the screw boss portions at the
rotary member). The numbers of the recessed portions 42 (and
protruding portions) and of the screw hole portions 36 (and screw
boss portions) are not limited to three. Furthermore, although not
shown in the drawings, the reels 10 and 20 according to the present
exemplary embodiment may also be employed in recording tape
cartridges in which only one reel is accommodated in a case.
* * * * *