JP5127958B2 - reel - Google Patents

Description

  The present invention relates to a reel on which a recording tape such as a magnetic tape used for storing data in a computer or the like is wound.

  2. Description of the Related Art Conventionally, there is a recording tape cartridge in which a recording tape such as a magnetic tape used as a data recording / reproducing medium (data backup) for a computer or the like is wound around a resin reel and the reel is accommodated in a single case. Are known. In such a reel of the recording tape cartridge, a hub around which the recording tape is wound and an upper flange and a lower flange that hold the end in the width direction of the recording tape may be formed separately (for example, , See Patent Document 1 and Patent Document 2).

  In such a three-piece (component) reel, the upper flange is welded to the upper end of the hub, and the lower flange is welded to the lower end of the hub. Therefore, when the hub is deformed due to the tightening of the recording tape, the upper flange and the lower flange welded to the hub may be deformed by the influence of the deformation. Further, when the upper flange and the lower flange are welded to the upper end portion and the lower end portion of the hub, respectively, there is a problem that the welding strength is not sufficiently ensured, for example, there is a possibility of peeling at the time of deformation.

JP 2002-133818 A JP 2005-108409 A

  In view of the above problems, an object of the present invention is to obtain a three-piece reel that can improve the rigidity of the hub and also improve the welding strength of the flange to the hub.

In order to achieve the above object, in the reel according to claim 1 of the present invention, an overhang portion that projects radially is formed on the inner peripheral surface of the cylindrical portion, and the recording tape is provided on the outer peripheral surface of the cylindrical portion. A hollow hub that is wound, a first flange that is provided on one end side of the hub and has a first extending portion that is welded to the protruding portion, and on the other end side of the hub And a second flange having a second extending portion welded to the overhang portion.

  According to the first aspect of the present invention, the first extending portion of the first flange and the second extending portion of the second flange are welded to the projecting portion formed on the inner peripheral surface of the hub. Therefore, the welding strength of the first flange and the second flange with respect to the hub can be improved, and the rigidity of the hub can be improved.

  A reel according to a second aspect is the reel according to the first aspect, wherein the projecting portion is formed in an annular shape.

  According to the second aspect of the present invention, since the projecting portion is formed in an annular shape, the welding strength of the first flange and the second flange to the hub can be further improved, and the rigidity of the hub can be further improved. it can.

  A reel according to a third aspect is the reel according to the first or second aspect, wherein the projecting portion is formed at a substantially center of the hub.

  According to the third aspect of the present invention, since the overhang portion is formed at substantially the center of the hub, the welding strength of the first flange and the second flange to the hub can be further improved, and the rigidity of the hub is further improved. Can be made.

  A reel according to a fourth aspect is the reel according to any one of the first to third aspects, wherein an overhang length of the overhang portion is equal to the first extension portion and the first overhang. 2 It is characterized by being the same as the thickness of the extending portion.

  According to the fourth aspect of the present invention, since the overhanging length of the overhanging portion is the same as the thickness of the first extending portion and the second extending portion, the braking member and release member provided in the hub There is no risk of interference with the overhang.

  As described above, according to the present invention, it is possible to provide a three-piece reel capable of improving the rigidity of the hub and improving the welding strength of the flange to the hub.

Schematic perspective view of recording tape cartridge Schematic exploded perspective view of the recording tape cartridge as seen from above Schematic exploded perspective view of the recording tape cartridge as seen from below Schematic exploded perspective view showing the configuration of the reel Schematic side cross-sectional view showing reel configuration Schematic plan view of reel hub Schematic side sectional view showing the recording tape cartridge before the drive gear of the rotating shaft is engaged Schematic side sectional view showing the recording tape cartridge after the drive gear of the rotating shaft is engaged

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, the schematic configuration of the recording tape cartridge 10 will be described, and then the reel 20 will be described. For convenience of explanation, the loading direction of the recording tape cartridge 10 into the drive device is indicated by an arrow A, and this is the forward direction (front side) of the recording tape cartridge 10.

  An arrow B direction orthogonal to the arrow A is a right direction (right side), and an arrow C direction orthogonal to the arrows A and B is an upward direction (upper side). In the following description, the “radial direction” refers to a direction parallel to a direction radially outward from the axis (center) line of the reel 20 accommodated in the case 12.

  As shown in FIGS. 1 to 3, the recording tape cartridge 10 has a case 12 having a substantially rectangular box shape. In the case 12, an upper case 14 and a lower case 16 made of resin such as polycarbonate (PC) are respectively provided with a peripheral wall 14B standing on the periphery of the top plate 14A, and a peripheral wall 16B standing on the periphery of the bottom plate 16A. Are joined together by ultrasonic welding, screwing, or the like.

  The right wall 12B of the case 12 is formed with an opening 18 for pulling out a recording tape T wound on a reel 20 described later, and a drive end of the recording tape T drawn out from the opening 18 has a drive A leader pin 30 that is pulled out while being locked (engaged) by a drawing member (not shown) of the apparatus is fixed.

  An annular groove 32 is formed at both ends of the leader pin 30 projecting from the widthwise end of the recording tape T, and the annular groove 32 is locked to a hook or the like of the drawing member. Thereby, when the recording tape T is pulled out, the hook or the like does not come into contact with the recording tape T to be damaged.

  Further, a pair of upper and lower pin holding portions for positioning and holding the leader pin 30 in the case 12 on the inner side of the opening 18 of the case 12, that is, the inner surface of the top plate 14A of the upper case 14 and the inner surface of the bottom plate 16A of the lower case 16. 36 is provided. The pin holding portion 36 has a substantially semicircular shape with the drawing tape T drawn side open, and both end portions 34 of the leader pin 30 in an upright state can enter and leave the pin holding portion 36 from the open side. Has been.

  In addition, a leaf spring 38 is fixedly disposed in the vicinity of the pin holding portion 36, and the bifurcated tip portion of the leaf spring 38 is engaged with the upper and lower end portions 34 of the leader pin 30. The leader pin 30 is held by the pin holding portion 36. When the leader pin 30 enters and exits the pin holding portion 36, the tip of the leaf spring 38 is appropriately elastically deformed to allow movement of the leader pin 30.

  The opening 18 is opened and closed by a door 50. The door 50 is formed in a substantially rectangular plate size that can close the opening 18, and the top plate 14 </ b> A and the bottom plate 16 </ b> A inside the opening 18 can be moved along the right wall 12 </ b> B of the case 12. Grooves 64 are formed in which the upper and lower ends of the door 50 are slidably fitted.

  A shaft 52 is projected from the center of the rear end of the door 50, and a coil spring 58 is inserted into the shaft 52. An enlarged portion 54 that prevents the coil spring 58 from falling off is formed at the rear end of the shaft 52. Further, the lower case 16 is provided with a support base 60 having a locking portion 62 that locks the rear end of the coil spring 58 inserted into the shaft 52.

  Accordingly, the door 50 is slidably supported on the support base 60 and the rear end of the coil spring 58 is locked to the locking portion 62, so that the door 50 is always urged by the urging force of the coil spring 58. The opening 18 is biased in the closing direction. When the opening 18 is opened, it is preferable that a support base 66 that supports the shaft 52 is further protruded on the rear side of the support base 60.

  Further, a projection 56 for opening / closing operation projects outwardly from the front end of the door 50. The convex portion 56 engages with an opening / closing member (not shown) on the drive device side as the recording tape cartridge 10 is loaded into the drive device. Thereby, the door 50 is configured to be opened against the urging force of the coil spring 58.

  In addition, a write protect 70 is set at the left rear portion of the case 12 so as to be slidable in the left-right direction. The write protect 70 is set on the rear wall of the case 12. An opening 68 for projecting the operation projection 72 for manually operating the is formed. The opening 68 is formed by a notch 68A formed in the peripheral wall 14B of the upper case 14 and a notch 68B formed in the peripheral wall 16B of the lower case 16 when the upper case 14 and the lower case 16 are joined. It is the structure formed.

  Furthermore, the lower case 16 is provided with a long hole 69 that exposes the protrusion 74 of the write protect 70 in the left-right direction, and when the recording tape cartridge 10 is loaded in the drive device, the drive The position of the write protect 70 is detected on the apparatus side, and it is automatically determined whether or not recording on the recording tape T is possible. The protrusion 74 does not protrude from the lower surface of the lower case 16.

  Next, the reel 20 and the brake member 80 that prevents the reel 20 from rotating when not in use (when not loaded in the drive device) will be described. Inside the case 12, only one reel 20 made of resin such as polycarbonate (PC) is rotatably accommodated.

  As shown in FIGS. 4 to 6, the reel 20 includes a cylindrical reel hub 22 constituting an axial center of the reel 20, an annular upper flange 24 provided on the upper end side thereof, and a lower end side thereof. It is comprised with the disk-shaped lower flange 26 provided. Then, a recording tape T such as a magnetic tape as an information recording / reproducing medium is wound around the outer peripheral surface of the reel hub 22, and an end portion in the width direction of the wound recording tape T by the upper flange 24 and the lower flange 26. Is retained.

  On the other hand, on the inner peripheral surface of the reel hub 22, an extending portion 22 </ b> A having a rectangular shape in a sectional view projecting a predetermined length L in the radial direction toward the rotation center of the reel 20 (reel hub 22) is annular at the center in the height direction. Projecting in the circumferential direction. Further, an annular extending portion 24A is erected at a predetermined height on the inner peripheral edge of the upper flange 24, and a predetermined position on the upper surface of the lower flange 26 and facing the annular extending portion 24A coaxially. The annular extending portion 26A is erected at a predetermined height.

  A plurality of (for example, three) ribs 26B for welding protrude from the upper surface of the annular extending portion 26A at equal intervals, and welding equivalent to the ribs 26B is also provided on the lower surface of the annular extending portion 24A. A plurality of (for example, three) ribs 24B (see FIG. 5) are provided at regular intervals. Thereby, the lower surface of the annular extending portion 24A is ultrasonically welded to the upper surface of the overhanging portion 22A, and the upper surface of the annular extending portion 26A is ultrasonically welded to the lower surface of the overhanging portion 22A.

  That is, the heights of the annular extending portion 24A and the annular extending portion 26A are about 1/2 each of the height excluding the height (thickness) H of the overhang portion 22A of the reel hub 22, The reel hub 22 is provided on the outer peripheral surface side of the annular extending portion 24A and the annular extending portion 26A so as not to be relatively rotatable by welding. Note that the height (thickness) H of the overhanging portion 22 </ b> A is smaller than the thickness W of the reel hub 22.

  In addition, one or more gates (not shown) that serve as a resin material inlet when the reel hub 22 is molded are provided on the distal end surface (radially inner surface) of the overhang portion 22A. Furthermore, the overhang length L in the radial direction of the overhang portion 22A is the same as the thickness (thickness) D of the extending portions 24A and 26A (L = D).

  Thus, the braking member 80 (described later) and the release member 90 (described later) inserted into the reel hub 22 do not reliably interfere with the overhanging portion 22A. Further, it is desirable that the lower flange 26 (extended portion 26A) provided with a reel gear 44 (described later) or the like, which requires positional accuracy with respect to the reel hub 22, be first in order of welding to the overhanging portion 22A.

  On the other hand, as shown in FIG. 1 to FIG. 3, a reel gear 44 is formed in an annular shape on the lower surface of the lower flange 26, and a gear for exposing the reel gear 44 to the outside at the approximate center of the lower case 16. An opening 40 is formed. The reel gear 44 exposed from the gear opening 40 is meshed with a drive gear 102 (see FIGS. 7 and 8) formed on the rotary shaft 100 of the drive device and is driven to rotate, so that the reel in the case 12 20 is rotatable relative to the case 12.

  An annular reel plate 46 made of a magnetic material is fixed to the inner surface in the radial direction of the reel gear 44 on the lower surface of the lower flange 26 by insert molding or the like, and an annular magnet (provided on the rotary shaft 100 of the drive device). It is attracted and held by a magnetic force (not shown). Further, the reel 20 is partially protruded from the inner surfaces of the upper case 14 and the lower case 16 so that the reel 20 is not rattled by the floating regulation wall 42 as an inner wall on a circular locus coaxial with the gear opening 40. Is held in.

  As shown in FIGS. 4 and 5, the engagement gear is located at a predetermined position that is radially inward of the annular extending portion 26 </ b> A of the lower flange 26 and on a circular locus coaxial with the lower flange 26. A plurality of 48 are erected at equal intervals (for example, three at intervals of 120 degrees), and the through holes 29 are equally spaced between the engagement gears 48 and at predetermined positions on the reel gear 44 in the bottom view. A plurality (three in this case at intervals of 120 degrees) are formed. A disc-shaped braking member 80 formed of a resin material such as polyacetal (POM) is inserted into the reel hub 22.

  As shown in FIGS. 1 to 3, a brake gear 84 that can mesh with the engagement gear 48 is formed in an annular shape on the periphery of the lower surface 80 </ b> A of the brake member 80. Then, on the upper surface of the braking member 80, a substantially cross-shaped groove portion in plan view, into which a rotation restricting rib 76 having a substantially cross shape in plan view that protrudes downward from the inner surface of the top plate 14A of the upper case 14 is inserted. The engaging wall portion 86 having 86 </ b> A is erected so as to be slightly higher than the height of the rotation restricting rib 76. As a result, the braking member 80 is configured to be non-rotatable with respect to the case 12 (upper case 14) and to be movable in the vertical direction while being guided in the reel hub 22 without being inclined.

  A compression coil spring 98 is disposed between the upper case 14 and the braking member 80. That is, one end of the compression coil spring 98 abuts on the inner side (between the rotation restricting rib 76 and the annular protrusion 78) of the annular protrusion 78 provided on the outer side of the rotation restricting rib 76 of the upper case 14, and the other end is the braking member. 80 is arranged in contact with an annular groove 88 provided on the upper surface of 80. As a result, the position of the compression coil spring 98 is not displaced in the radial direction, and the braking member 80 is constantly urged downward by the urging force of the compression coil spring 98.

  Therefore, when the recording tape cartridge 10 is not in use (when not loaded in the drive device), the braking gear 84 is always meshed with the engagement gear 48 and the relative rotation of the reel 20 with respect to the case 12 is prevented. The rotation is locked. At this time, the reel 20 is pressed against the lower case 16 side by this urging force, and the reel gear 44 is exposed from the gear opening 40. In addition, in order to prevent rattling (radial position deviation) in the reel hub 22 of the braking member 80, the inner circumferential surface of the annular extending portion 26A is provided with a position regulating rib having a length extending over the entire height. A plurality of projections 28 are provided at equal intervals (see FIGS. 4 and 5).

  Further, in the reel hub 22 and on the lower side of the braking member 80 (between the lower flange 26 and the braking member 80), a substantially regular triangle in plan view formed of a resin material such as polybutylene terephthalate (PBT), for example. A release member 90 having a shape is provided. The release member 90 is provided with a plurality of through holes 92 (three in the figure are hexagonal in the figure) formed in a predetermined shape at appropriate positions, so that the release member 90 is reduced in weight. .

  Further, on the lower surface of each release member 90 and at each apex portion, a substantially columnar leg portion 94 that protrudes downward from the reel gear 44 of the lower flange 26 by a predetermined height through the through hole 29 is projected. Yes. Accordingly, the leg 94 is pushed up and the braking member 80 is pushed up via the release member 90 in accordance with the operation in which the drive gear 102 of the rotary shaft 100 meshes with the reel gear 44.

  At this time, the leg portion 94 is configured not to be completely removed from the through-hole 29 even if the release member 90 rises to the uppermost position (usually about 2 mm to 3 mm). In addition, a planar portion 96 having a circular shape in plan view is formed at the center of the upper surface of the release member 90, and a substantially hemispherical release protrusion 82 protruding from the center of the lower surface 80A of the braking member 80 comes into contact therewith. (See FIGS. 7 and 8). Therefore, the contact area between the braking member 80 and the release member 90 is reduced, and the sliding resistance during use (when the reel 20 rotates) is reduced.

  Next, the operation of the recording tape cartridge 10 and the reel 20 configured as described above will be described. In the recording tape cartridge 10 having the above-described configuration, the opening 18 is closed by the door 50 when not in use (when stored or transported). The recording tape T is wound around the outer peripheral surface of the reel hub 22 of the reel 20.

  Here, the reel hub 22 has an overhanging portion 22A, which has a rectangular shape in cross-section, extending over a predetermined length L in the radial direction of the reel 20 (reel hub 22) at the center of the inner circumferential surface in the height direction. And projecting annularly. The height (thickness) H of the overhang portion 22 </ b> A is formed to be smaller than the thickness W of the reel hub 22. In addition, one or more gates (not shown) serving as a resin material inlet when the reel hub 22 is molded are provided on the distal end surface (radial inner surface) of the overhang portion 22A.

  Therefore, when the reel hub 22 is molded, the resin material injected from the gate flows favorably from the overhang portion 22A to the upper end portion and the lower end portion of the reel hub 22. Therefore, even in the reel hub 22 in which the overhanging portion 22A is formed, it is possible to prevent contraction deformation due to different cooling times of the resin material. That is, even the reel hub 22 in which the overhanging portion 22A is formed can be accurately molded.

  When the reel 20 is assembled, the extended portion 26A of the lower flange 26 is first welded to the overhang portion 22A, and then the extended portion 24A of the upper flange 24 is welded. Therefore, centering of the reel gear 44 with respect to the reel hub 22 (positioning so that the rotation centers coincide) can be performed with high accuracy.

  Further, since the extended portions 24A and 26A standing on the upper flange 24 and the lower flange 26 are welded to the overhanging portion 22A of the reel hub 22, the upper flange 24 and the lower flange 26 are welded to the reel hub 22. It is easy to peel off and the welding strength can be improved.

  Further, the reel hub 22 is provided on the outer peripheral surface side of the extending portions 24A and 26A, and the overhanging portion 22A is provided in an annular shape on the inner peripheral surface side of the reel hub 22, so that the rigidity of the reel hub 22 is improved. Can be made. Therefore, even if the winding amount of the recording tape T is increased and the winding tightening force is increased, the reel hub 22 can be prevented from being collapsed inward in the radial direction. Further, since the overhang length L of the overhang portion 22A is the same as the thickness (thickness) D of the extension portions 24A and 26A (L = D), the brake member 80 and the release member 90 are There is no possibility of interfering with the overhanging portion 22A.

  When the recording tape T is used, the recording tape cartridge 10 is loaded into the drive device along the arrow A direction with the front wall 12A at the head. Then, first, the opening / closing member provided on the drive device side engages with the convex portion 56 of the door 50. In this state, when the recording tape cartridge 10 further moves in the arrow A direction, the opening / closing member moves the projection 56 relatively rearward against the urging force of the coil spring 58. Then, the door 50 on which the convex portion 56 projects is slid rearward in the groove portion 64 along the right wall 12B to open the opening 18.

  Thus, when the recording tape cartridge 10 is loaded into the drive device to a predetermined depth and the opening 18 is completely opened, a positioning member (not shown) of the drive device is moved to a positioning hole (not shown) formed in the lower case 16. (Not shown). Here, “relative” means that the recording tape cartridge 10 is lowered and the positioning member may be raised. Thus, the recording tape cartridge 10 is accurately positioned at a predetermined position in the drive device, and further sliding (rearward movement) of the door 50 is restricted.

  When the recording tape cartridge 10 is positioned at a predetermined position, the rotary shaft 100 relatively enters from the gear opening 40 and meshes the drive gear 102 with the reel gear 44. Then, as the drive gear 102 meshes with the reel gear 44, the leg portion 94 protruding on the reel gear 44 is pushed up against the urging force of the compression coil spring 98 and is braked via the release member 90. The member 80 is pushed upward, and the meshing between the brake gear 84 and the engagement gear 48 is released.

  The reel plate 46 is attracted and held by the magnetic force of an annular magnet (not shown) provided inside the drive gear 102 in a state where the drive gear 102 and the reel gear 44 are completely engaged with each other. No. 20 is unlocked in the case 12 so that the reel gear 44 can be rotated relative to the case 12 while maintaining the meshing of the reel gear 44 with the drive gear 102 (see FIG. 8).

  On the other hand, a drawing member provided on the drive device side enters the case 12 from the opened opening 18 and grips and pulls out the leader pin 30 positioned and held by the pin holding portion 36. At this time, since the recording tape cartridge 10 is accurately positioned in the drive device, the drawing member can reliably engage the hook with the annular groove 32 of the leader pin 30. Further, since the rotation lock state of the reel 20 is released, the reel 20 can rotate as the leader pin 30 is pulled out.

  Thus, the leader pin 30 extracted from the opening 18 is accommodated in a take-up reel (not shown). Then, by rotating the take-up reel and the reel 20 synchronously, the recording tape T is sequentially drawn out from the case 12 while being taken up by the take-up reel, and is arranged along a predetermined tape path. Information is recorded or reproduced by a recording / reproducing head (not shown).

  When the recording tape cartridge 10 that has finished recording and reproducing information is ejected from the drive device, first, the recording shaft T is rewound onto the reel 20 by the reverse rotation of the rotary shaft 100. When the recording tape T is rewound to the end of the reel 20 and the leader pin 30 is held by the pin holding portion 36, the positioning member is relatively extracted from the positioning hole, and the rotating shaft 100 is also pulled out. Is relatively extracted from the gear opening 40, and the meshing of the drive gear 102 with the reel gear 44 is released.

  Then, the braking member 80 and the release member 90 are pressed downward by the urging force of the compression coil spring 98, and the leg portion 94 inserted through the through hole 29 has a predetermined height from the lower surface of the lower flange 26 on the reel gear 44. The brake gear 84 meshes with the engagement gear 48 while projecting downward. Thereby, the reel 20 is again in the rotation locked state in which the relative rotation in the case 12 is prevented (see FIG. 7).

  Thereafter, the recording tape cartridge 10 is moved in the direction opposite to the arrow A direction by an unillustrated ejecting mechanism. Then, with this movement, the door 50 slides in the closing direction of the opening 18 by the urging force of the coil spring 58 and completely closes the opening 18 (returns to the initial state). Thus, the relative rotation of the reel 20 with respect to the case 12 is locked, and the recording tape cartridge 10 with the opening 18 closed is completely ejected from the drive device.

  As described above, the annular protruding portion 22A is formed on the inner peripheral surface of the reel hub 22, and the annular extending portion 26A of the lower flange 26 and the annular extending portion of the upper flange 24 are formed on the annular protruding portion 22A. Since 24A is configured to be welded in this order, the centering of the reel gear 44 with respect to the reel hub 22 can be accurately performed, the welding strength can be increased, and the rigidity of the reel hub 22 can be further increased.

  Therefore, even if the winding amount of the recording tape T is increased, the reel hub 22 can be prevented from falling and deforming. That is, this makes it possible to obtain the recording tape cartridge 10 that can sufficiently cope with an increase in recording capacity. In addition, since the deformation of the reel hub 22 is excellent, damage to the recording tape T during long-term storage can be reduced.

  It should be noted that the overhanging portion 22A is preferably provided at the center in the height direction (vertical direction) of the reel hub 22, but may be slightly shifted in the vertical direction. Therefore, in the said embodiment, the position of 22 A of overhang | projection parts is made into the approximate center in a height direction. Accordingly, the heights of the extending portions 24A and 26A may be finely adjusted as appropriate.

  Moreover, in the said embodiment, although it was set as the structure which has the leader pin 30 as a leader member, it is good also as a structure which has a leader block (illustration omitted) and a leader tape (illustration omitted), and the door 50 which opens and closes the opening 18 is also provided. For example, it may be configured to move along a predetermined arc (not shown).

  In the above embodiment, the recording tape cartridge 10 in which the single reel 20 is accommodated has been described. However, the present invention can also be applied to a recording tape cassette (not shown) in which two reels 20 are accommodated. Further, the recording tape T only needs to be understood as a long tape-like information recording / reproducing medium capable of recording information and reproducing the recorded information, and the recording tape cartridge 10 (reel 20) can be any recording / reproducing system. Needless to say, the present invention can also be applied to the recording tape T.

DESCRIPTION OF SYMBOLS 10 Recording tape cartridge 12 Case 20 Reel 22 Reel hub 22A Overhang | projection part 24 Upper flange (1st flange)
24A extension part (first extension part)
26 Lower flange (2nd flange)
26A extension part (second extension part)
DESCRIPTION OF SYMBOLS 29 Through-hole 30 Leader pin 44 Reel gear 48 Engagement gear 80 Brake member 82 Release protrusion 84 Brake gear 90 Release member 94 Leg part 100 Rotating shaft 102 Drive gear

Claims (4)

A hollow hub is formed on the inner peripheral surface of the cylindrical portion so as to project in the radial direction, and a recording tape is wound around the outer peripheral surface of the cylindrical portion ;
A first flange provided on one end side of the hub and having a first extending portion welded to the overhang portion;
A second flange provided on the other end side of the hub and having a second extending portion welded to the overhang portion;
A reel characterized by comprising.   The reel according to claim 1, wherein the projecting portion is formed in an annular shape.   The reel according to claim 1, wherein the projecting portion is formed at a substantially center of the hub.   4. The reel according to claim 1, wherein an overhanging length of the overhanging portion is the same as a thickness of the first extending portion and the second extending portion. .

Images