Tape reels and tape cartridges

Abstract

To provide a tape reel with a cylindrical portion having a shape close to a perfect circle and a tape cartridge having the tape reel with the cylindrical portion having a shape close to a perfect circle.SOLUTION: A tape reel includes a cylindrical portion and a bottom portion having an upright surface on which the cylindrical portion stands. The upright surface includes a central surface located on a center side of the bottom portion and a first inclined surface that is formed along a circumferential direction of the cylindrical portion on the outer peripheral portion of the central surface and inclines so that the wall thickness of the bottom portion gradually reduces toward the outer peripheral portion. A through hole passing through the bottom portion is formed on the outer peripheral portion, a pair of wall portions stand on the first inclined surface on both ends of the through hole in the circumferential direction, and a second inclined surface, whose inclined angle with respect to the central surface is smaller than the inclined angle of the first inclined portion, is formed on a surface continuous with the central surface of each wall portion.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The technology of the present disclosure relates to a tape reel and a tape cartridge. [Background technology]

[0002] Patent Document 1 discloses a reel having a cylindrical hub molded from a resin material and having a bottom with an open upper end, a lower flange integrally molded with the hub on the lower end side of the hub, an annular upper flange facing the lower flange, and a welded portion joining the lower surface of the upper flange to the upper end surface of the hub.

[0003] Patent Document 2 discloses a tape reel that has a hub including a bottom and a cylindrical portion protruding from the bottom, with a gear formed in the bottom along the circumferential direction of the cylindrical portion, a first hole formed inside the cylindrical portion, and a second hole formed in the bottom between the gear and the inner wall surface of the cylindrical portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-15191 [Patent Document 2] Japanese Patent Application Laid-Open No. 2010-44845 Summary of the Invention

[0005] One embodiment of the technique of the present disclosure provides a tape reel having a cylindrical portion with improved roundness, and a tape cartridge including a tape reel having a cylindrical portion with improved roundness. [Means for solving the problem]

[0006] A first aspect of the technology disclosed herein is a tape reel comprising a cylindrical portion and a bottom portion having an upright surface from which the cylindrical portion stands, the upright surface having a central surface located on the center side of the bottom portion and a first inclined surface formed on the outer periphery of the central surface along the circumferential direction of the cylindrical portion and inclined so that the thickness of the bottom portion gradually decreases toward the outer periphery, a through hole penetrating the bottom portion is formed in the outer periphery, a pair of wall portions are erected on the first inclined surface on both circumferential sides of the through hole, and a second inclined surface is formed on the surface connected to the central surface of each wall portion, the inclination angle relative to the central surface being smaller than the inclination angle of the first inclined surface.

[0007] A second aspect of the technique of the present disclosure is the tape reel according to the first aspect, in which the ratio of the angle of inclination of the second inclined surface to the angle of inclination of the first inclined surface is not less than 0.03 and not more than 0.5.

[0008] A third aspect of the technology of the present disclosure is a tape reel according to the first or second aspect, having a tapered surface formed on the opening edge of the through hole on the second inclined surface side and flaring toward the second inclined surface side.

[0009] A fourth aspect of the technology of the present disclosure is a tape reel according to any one of the first to third aspects, in which a plurality of through holes are formed at intervals in the circumferential direction, and each wall portion is erected on both circumferential sides of the through hole.

[0010] A fifth aspect of the technology of the present disclosure is a tape cartridge having a tape reel of any one of the first to fourth aspects, and a case that rotatably supports the tape reel and houses the tape reel and a tape wound around the tape reel. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view showing a tape cartridge equipped with a tape reel according to a first embodiment. FIG. [Figure 2] 1 is an exploded perspective view showing a tape cartridge including a tape reel according to a first embodiment, as viewed from above. [Figure 3]1 is an exploded perspective view showing a tape cartridge including a tape reel according to a first embodiment, as viewed from below. FIG. [Figure 4] 1 is a perspective view showing a tape reel according to a first embodiment, with a partially enlarged cross section; [Figure 5] FIG. 2 is a partially enlarged perspective view of the tape reel according to the first embodiment. [Figure 6] FIG. 2 is a partially enlarged plan view of the tape reel according to the first embodiment, along with a graph of the roundness of the hub. [Figure 7] FIG. 2 is a partially enlarged perspective view of the tape reel according to the first embodiment. [Figure 8] FIG. 2 is a partially enlarged perspective view of a tape reel according to a first comparative example. [Figure 9] FIG. 10 is a partially enlarged perspective view of a tape reel according to a second comparative example. [Figure 10] 4 is an explanatory diagram illustrating the inclination angles of a first inclined surface and a second inclined surface of the tape reel. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] An example of an embodiment of the technology of the present disclosure will be described with reference to the accompanying drawings.

[0013] As shown in FIG. 1, the tape cartridge 10 has a case 12. One tape reel 20 is housed in the case 12. A recording tape T is wound around the tape reel 20. Details of the case 12 and the tape reel 20 will be described later. The case 12 is an example of a "case" according to the technology of the present disclosure. The tape reel 20 is an example of a "tape reel" according to the technology of the present disclosure. The tape cartridge 10 is an example of a "tape cartridge" according to the technology of the present disclosure.

[0014] The tape cartridge 10 is inserted into a drive device (not shown). In the drive device, the recording tape T is unwound from the tape cartridge 10, and information is written to and read from the recording tape T.

[0015] In the drawings, the loading direction of the tape cartridge 10 into the drive device is indicated by arrow A. The direction indicated by arrow A is the forward direction of the tape cartridge 10. The direction indicated by arrow B, which is perpendicular to arrow A, is the rightward direction of the tape cartridge 10, and the direction indicated by arrow C, which is perpendicular to arrows A and B, is the upward direction of the tape cartridge 10 and the tape reel 20. In the following, the radial and circumferential directions of the tape reel 20 may be simply referred to as the "radial direction" and the "circumferential direction." The above-mentioned forward, rightward, and upward directions are defined for convenience and do not limit the orientation of the tape cartridge according to the technology of the present disclosure.

[0016] As shown in Figures 1 to 3, the case 12 is formed in the shape of a flat rectangular box. The case 12 has an upper case 14 and a lower case 16. A peripheral wall 14B is provided on the periphery of a top plate 14A of the upper case 14, and a peripheral wall 16B is provided on the periphery of a bottom plate 16A of the lower case 16. With the lower end of the peripheral wall 14B and the upper end of the peripheral wall 16B in contact with each other, the upper case 14 and the lower case 16 are joined by ultrasonic welding and / or screw fastening, for example. The upper case 14 and the lower case 16 are made of resin, such as polycarbonate (PC), for example.

[0017] 2 and 3, screw bosses 15 are formed near the corners of the upper case 14 and the lower case 16. Screws (not shown) are threaded into the screw bosses 15 from the underside of the lower case 16, joining the upper case 14 and the lower case 16 to assemble the case 12. A resin tape reel 20 is rotatably housed inside the case 12.

[0018] The tape reel 20 has a hub 22, an upper flange 24, and a lower flange 26. The hub 22 is an example of a "cylindrical portion" according to the technology of the present disclosure. The hub 22 is formed into a cylindrical shape with an open upper end and a closed bottom. The upper flange 24 is formed into an annular shape, and the lower flange 26 is also formed into an annular shape. The upper flange 24 and the lower flange 26 face each other.

[0019] In this embodiment, the upper flange 24 is ultrasonically welded to the upper end of the hub 22. In contrast, the lower flange 26 is molded integrally with the hub 22 at the lower end of the hub 22. In other words, the hub 22 and the lower flange 26 constitute a hub member 100 with a lower flange.

[0020] Recording tape T is wound around the outer peripheral surface of hub 22. Recording tape T is an example of a magnetic tape or the like as an information recording and reproducing medium. The positions of both widthwise ends of the wound recording tape T are regulated by an upper flange 24 and a lower flange 26 that face each other in parallel.

[0021] The hub 22 has a bottom wall 28 formed on one axial end side of the hub 22, specifically the base end side. The bottom wall 28 is an example of a "bottom" according to the technology of the present disclosure. The bottom wall 28 is perpendicular to the hub 22. The hub 22 stands upright from an upper surface 33 of the bottom wall 28. The upper surface 33 is an example of an "upright surface" according to the technology of the present disclosure. For convenience, the direction in which the hub 22 stands upright from the bottom wall 28 is referred to as the upward direction of the tape reel 20 according to the technology of the present disclosure. Furthermore, for convenience, the direction opposite to the direction in which the hub 22 stands upright from the bottom wall 28 is referred to as the downward direction of the tape reel 20 according to the technology of the present disclosure. For example, the "upper side of the tape reel 20" refers to the side of the tape reel 20 on which the hub 22 stands upright, and the "lower side of the tape reel 20" refers to the side of the tape reel 20 on which the hub 22 stands upright. The aforementioned forward, rightward, and upward directions are also defined for the sake of convenience and do not limit the orientation of the tape cartridge according to the technology of the present disclosure. A reel gear 44 is formed in an annular shape on the lower surface (outer surface) of the bottom wall 28.

[0022] A gear opening 40 is formed in the center of the lower case 16 to expose the reel gear 44 to the outside of the case 12. The reel gear 44 exposed from the gear opening 40 is meshed with a drive gear (not shown) formed on a rotating shaft (not shown) of the drive device. The reel gear 44 is then driven to rotate by the drive gear, causing the tape reel 20 to rotate relative to the case 12 within the case 12.

[0023] A reel plate 46 is fixed to the underside of the bottom wall 28, radially inward of the reel gear 44. The reel plate 46 is a disk-shaped metal plate made of a magnetic material. The reel plate 46 is fixed coaxially and integrally with the hub 22, for example, by insert molding. The reel plate 46 is attracted and held by the magnetic force of an annular magnet (not shown) provided on the rotating shaft of the drive device.

[0024] A plurality of play restriction walls 42 are provided partially on the inner surfaces of the upper case 14 and the lower case 16. Each play restriction wall 42 is formed in an arc shape that is concentric with the gear opening 40. By being surrounded by the plurality of play restriction walls 42, the tape reel 20 is held in place so as not to rattle in the radial direction.

[0025] An opening 18 is formed in the right wall of the case 12. The recording tape T wound around the tape reel 20 can be pulled out through the opening 18.

[0026] A leader pin 30 is fixed to the free end of the recording tape T that is pulled out from the opening 18. The leader pin 30 is engaged with a pull-out member (not shown) of the drive device and is operated to pull out the tape. Both ends of the leader pin 30 protrude beyond the width direction ends of the recording tape T. An annular groove 32 is formed at each end of the leader pin 30. The annular groove 32 is engaged with a hook or the like of the pull-out member of the drive device.

[0027] A pair of pin holding portions 36 are provided inside the opening 18 of the case 12. In the example shown in Fig. 2, each pin holding portion 36 is provided facing 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. The pin holding portions 36 position and hold the leader pin 30 inside the case 12. The pin holding portion 36 has a generally semicircular shape that is open on the side from which the recording tape T is pulled out. Both ends 34 of the leader pin 30 can enter and exit the pin holding portion 36 from the open side of the pin holding portion 36.

[0028] A leaf spring 38 is fixed inside the case 12. The leaf spring 38 is disposed inside the case 12 relative to the pin holding portion 36. The leaf spring 38 has a bifurcated tip. Each tip of the leaf spring 38 engages with both upper and lower ends 34 of the leader pin 30, thereby holding the leader pin 30 in the pin holding portion 36. When the leader pin 30 moves in and out of the pin holding portion 36, each tip of the leaf spring 38 elastically deforms appropriately, allowing the leader pin 30 to move.

[0029] The case 12 is provided with a door 50. The door 50 is formed in the shape of a rectangular plate large enough to close the opening 18. Grooves 64 are formed in the top plate 14A and bottom plate 16A inside the opening 18. The upper and lower ends of the door 50 are slidably fitted into the grooves 64, respectively. This allows the door 50 to move along the right wall of the case 12 to open and close the opening 18.

[0030] A shaft 52 protrudes from the rear end of the door 50. A coil spring 58 is inserted into the shaft 52. An expanded portion 54 is formed at the rear end of the shaft 52. The expanded portion 54 prevents the coil spring 58 from falling off the shaft 52. A support base 60 having a locking portion 62 protrudes from the lower case 16. The rear end of the coil spring 58 inserted into the shaft 52 is locked to the locking portion 62.

[0031] The shaft 52 is slidably supported on a support base 60, and the rear end of the coil spring 58 is engaged with an engaging portion 62. As a result, the door 50 is constantly urged in the direction of closing the opening 18 by the urging force of the coil spring 58.

[0032] A protrusion 56 protrudes outward from the front end of the door 50. When the tape cartridge 10 is inserted into the drive device, the protrusion 56 engages with an opening / closing member (not shown) on the drive device side. The opening / closing member on the drive device applies a force to the protrusion 56 toward the opening side of the door 50, causing the door 50 to open against the biasing force of the coil spring 58.

[0033] A write protector 70 is provided on the left rear portion of the case 12. The write protector 70 is slidable in the left and right directions.

[0034] The write protector 70 is a member that sets whether recording is "allowed" or "not allowed" on the recording tape T. The write protector 70 is formed with an operating protrusion 72 for manually sliding the write protector 70 left and right.

[0035] An opening 68 is formed in the rear wall of the case 12. The operating protrusion 72 protrudes from the opening 68 to the outside of the case 12. In the example shown in Figures 2 and 3, a notch 68A is formed in the peripheral wall 14B of the upper case 14, and a notch 68B is formed in the peripheral wall 16B of the lower case 16. When the upper case 14 and the lower case 16 are joined together, the opening 68 is formed by the notch 68A and the notch 68B.

[0036] A protrusion 74 is formed on the write protect 70. A long hole 69 is formed in the lower case 16. The longitudinal direction of the long hole 69 coincides with the left-right direction of the case 12. The protrusion 74 is exposed to the outside of the case 12 from the long hole 69. When the tape cartridge 10 is loaded in the drive device, the position of the protrusion 74 is detected on the drive device side to determine whether recording onto the recording tape T is "possible" or "not possible."

[0037] A plurality of engagement gears 48 are provided on the periphery of the upper surface of the bottom wall 28 of the hub 22. The plurality of engagement gears 48 are spaced apart (e.g., equally spaced) around the hub 22. A plurality of through holes 29 are formed between the plurality of engagement gears 48 and above the reel gear 44. In the example shown in FIG. 2, there are three engagement gears 48. The three engagement gears 48 are arranged at intervals of 120 degrees around the hub 22. The number of through holes 29 is also three. As shown in FIG. 6, the three through holes 29 are also arranged at intervals of 120 degrees around the hub 22. The through holes 29 are an example of a "through hole" according to the technology of the present disclosure. Note that FIG. 6 shows a plan view of the hub 22 as seen from above and a graph showing the circularity of the hub 22. The graph in FIG. 6 emphasizes the deviation from a perfect circle in the planar shape of the hub 22.

[0038] A braking member 80 is disposed inside the hub 22. The braking member 80 is, for example, a disk-shaped member molded from a resin material. The cylindrical cavity of the hub 22 is a space capable of accommodating a braking mechanism including the braking member 80. Furthermore, the hole 25A of the upper flange 24 is a hole through which the braking mechanism can pass and operate.

[0039] An annular brake gear 84 is formed on the periphery of the lower surface 80A of the brake member 80. The brake gear 84 is capable of meshing with the engagement gear 48.

[0040] A rotation-restricting rib 76 protrudes downward from the inner surface of the top plate 14A of the upper case 14. The rotation-restricting rib 76 has a cross shape in a plan view. An engagement protrusion 86, which also has a cross shape in a plan view, protrudes from the upper surface of the braking member 80. The height of the engagement protrusion 86 is greater than the height of the rotation-restricting rib 76. When the rotation-restricting rib 76 is inserted inside the engagement protrusion 86, the braking member 80 becomes unable to rotate relative to the case 12 (specifically, the upper case 14), and becomes movable up and down within the hub 22.

[0041] A compression coil spring 98 is disposed between the upper case 14 and the braking member 80. The braking member 80 is urged downward by the urging force of the compression coil spring 98. As shown in FIG. 3, an annular protrusion 78 protrudes from the outer side of the rotation-restricting rib 76 of the upper case 14. One end of the compression coil spring 98 is located inside the annular protrusion 78 (specifically, between the rotation-restricting rib 76 and the annular protrusion 78). In addition, as shown in FIG. 2, an annular groove 88 is formed in the upper surface of the braking member 80. The other end of the compression coil spring 98 is located within the annular groove 88.

[0042] When the tape cartridge 10 is not in use (i.e., not loaded in a drive device), the brake gear 84 meshes with the engagement gear 48. Because the brake gear 84 meshes with the engagement gear 48, the tape reel 20 is prevented from rotating relative to the case 12. The tape reel 20 is then pushed toward the lower case 16 by the biasing force of the compression coil spring 98, exposing the reel gear 44 from the gear opening 40.

[0043] A release member 90 is disposed inside the hub 22. The release member 90 is located below the braking member 80 (specifically, between the bottom wall 28 and the braking member 80). The release member 90 is a member molded from a resin material and shaped like an equilateral triangle in a plan view. A plurality of through holes 92 are formed in the release member 90, which contributes to reducing the weight of the release member 90.

[0044] A plurality of legs 94 protrude from the underside of the release member 90. In the example shown in Figures 2 and 3, the legs 94 are provided at each vertex of the release member 90. The legs 94 are inserted into the through holes 29 and protrude above the reel gear 44 from the underside of the bottom wall 28.

[0045] As shown in Figure 2, a support protrusion 96 is formed in the center of the upper surface of the release member 90. As shown in Figure 3, a hemispherical release projection 82 is provided in the center of the lower surface 80A of the brake member 80. The release projection 82 is in contact with the support protrusion 96. This reduces the contact area between the brake member 80 and the release member 90, thereby reducing sliding resistance when in use (i.e., when the tape reel 20 is rotating). The brake member 80 can be made of, for example, polyacetal (POM). The release member 90 can be made of, for example, polybutylene terephthalate (PBT).

[0046] 4, a short cylindrical portion 25 is provided on the inner peripheral side (specifically, the inner peripheral edge) of the upper flange 24. The short cylindrical portion 25 is inserted into the inside of the hub 22 so as to fit along the inner peripheral surface of the hub 22.

[0047] As also shown in FIG. 5, a plurality of restriction ribs 22C extending in the vertical direction are formed on the inner peripheral surface of the hub 22. The plurality of restriction ribs 22C are formed at equal intervals in the circumferential direction. When the braking member 80 moves up and down inside the hub 22, the radial position of the braking member 80 is restricted from the outside. In addition, a plurality of protrusions 22D are formed on the inner peripheral surface of the hub 22. Each protrusion 22D extends in the vertical direction separately from each restriction rib 22C. The number of protrusions 22D is, for example, six. The plurality of protrusions 22D are formed at equal intervals in the circumferential direction.

[0048] 5 to 7, the top surface 33 of the bottom wall 28 has a central surface 33A and a first inclined surface 33B. The central surface 33A is an example of the "central surface" according to the technology of the present disclosure. The first inclined surface 33B is an example of the "first inclined surface" according to the technology of the present disclosure.

[0049] The central surface 33A is located on the central side of the bottom wall 28. In contrast, the first inclined surface 33B is located on the radially outer side of the bottom wall 28, i.e., on the outer periphery side. The first inclined surface 33B is continuous with the central surface 33A at an outer periphery 33C of the central surface 33A and is formed along the circumferential direction. The first inclined surface 33B is inclined with respect to the central surface 33A. Specifically, the first inclined surface 33B is inclined downward (opposite the side on which the hub 22 is erected) toward the radially outer side, i.e., toward the outer periphery. As shown in FIG. 10, the inclination angle of the first inclined surface 33B with respect to the central surface 33A is hereinafter referred to as inclination angle θ1. Due to the formation of the first inclined surface 33B, the thickness T1 (see FIG. 4) of the bottom wall 28 gradually decreases toward the outer periphery.

[0050] The plurality of through holes 29 are all formed in the outer peripheral portion 33C, penetrating the bottom wall .

[0051] A pair of wall portions 35 are provided on both circumferential sides of each through hole 29. Each wall portion 35 is provided on the first inclined surface 33B. The wall portions 35 are connected to the hub 22 on the outer circumferential side. The wall portions 35 are an example of a "wall portion" according to the technology of the present disclosure.

[0052] The wall portion 35 prevents foreign matter from passing through the through-hole 29 and entering the inside of the hub 22 when the leg portion 94 of the release member 90 is not inserted through the through-hole 29.

[0053] The upper surface of the wall portion 35 is a second inclined surface 35A. The second inclined surface 35A is an example of the "second inclined surface" according to the technology of the present disclosure. The second inclined surface 35A is continuous with the central surface 33A and is inclined relative to the central surface 33A. Specifically, the second inclined surface 35A is inclined downward (opposite the side on which 22 is erected) toward the radially outward, i.e., outer periphery. As shown in FIG. 10, the inclination angle of the second inclined surface 35A relative to the central surface 33A is hereinafter referred to as inclination angle θ2. The inclination angle θ2 of the second inclined surface 35A is smaller than the inclination angle θ1 of the first inclined surface 33B.

[0054] A tapered surface 37 is formed in each through hole 29. The tapered surface 37 is an example of a "tapered surface" according to the technology of the present disclosure. The tapered surface 37 is formed on the opening edge of the through hole 29 on the second inclined surface 35A side, i.e., on the upper opening edge of the through hole 29. The tapered surface 37 is formed on the remaining edge 29B of the through hole 29 excluding the edge 29A on the hub 22 side, and forms a C-shape when viewed from above (the side on which the hub 22 is erected). The tapered surface 37 has a shape that widens from the center of the through hole 29 toward the second inclined surface 35A side (i.e., the radially outer side of the through hole 29). In other words, when each leg 94 of the release member 90 inserted into the through hole 29 from the second inclined surface 35A side comes into contact with the tapered surface 37, the tapered surface 37 is oriented to guide the leg 94 toward the center of the through hole 29 as it is inserted into the through hole 29.

[0055] Next, the operation of this embodiment will be described.

[0056] The lower flanged hub member 100 of this embodiment is formed (manufactured) by injection molding a resin using a mold. In injection molding, resin is injected into a cavity of a mold, and the injected resin shrinks as it cools and solidifies.

[0057] The lower flanged hub member 100 is formed with a first inclined surface 33B that is inclined at an inclination angle θ1 with respect to the central surface 33A. A wall portion 35 is erected on the first inclined surface 33B. The wall portion 35 is formed with a second inclined surface 35A that is inclined at an inclination angle θ2 with respect to the central surface 33A.

[0058] Here, Figure 8 shows a partially enlarged view of a bottom flanged hub member 110 of a first comparative example, and Figure 9 shows a partially enlarged view of a bottom flanged hub member 120 of a second comparative example. In the first and second comparative examples, elements, members, etc. that are the same as those in the first embodiment are designated by the same reference numerals as in the first embodiment.

[0059] In the lower flange-equipped hub member 110 of the first comparative example shown in FIG. 8 , the upper surface 35B of the wall portion 35 is flush with the central surface 33A. That is, the upper surface 35B is not inclined relative to the central surface 33A of the bottom wall 28. The wall portion 35 is connected to the hub 22 on the outer periphery. In the first comparative example, because the upper surface 35B is not inclined relative to the central surface 33A, the area connected to the hub 22 is larger than in this embodiment. Therefore, in the lower flange-equipped hub member 110 of the first comparative example, when the resin shrinks during injection molding, the resistance of the wall portion 35 to the shrinkage of the hub 22 is greater in the portion where the wall portion 35 is formed than in this embodiment. As a result, the portion of the hub 22 where the wall portion 35 is formed may bulge radially outward compared to the portion where the wall portion 35 is not formed.

[0060] In the bottom flanged hub member 120 of the second comparative example shown in Figure 9, the wall portion 35 (see Figure 7) is not formed on the first inclined surface 33B, and the first inclined surface 33B is continuous to the edge 29B of the through hole 29. That is, in the bottom flanged hub member of the second comparative example, when the resin shrinks during injection molding, there is no wall portion 35 that acts as a resistance to the shrinkage of the hub 22, and therefore the hub 22 has a shape with improved roundness compared to the bottom flanged hub member 110 of the first comparative example in which the wall portion 35 is formed. However, because the wall portion 35 is not formed, foreign matter is more likely to pass through the through hole 29 and enter the inside of the hub 22 than in a structure in which the wall portion 35 is formed.

[0061] In contrast, the lower flanged hub member 100 of this embodiment has a wall portion 35 formed therein, and therefore, compared to the lower flanged hub member of the second comparative example in which the wall portion 35 is not formed, foreign matter can be prevented from passing through the through hole 29 and entering the inside of the hub 22.

[0062] Furthermore, in the bottom flange-equipped hub member 100 of this embodiment, a second inclined surface 35A is formed on the wall portion 35. That is, in the bottom flange-equipped hub member 100 of this embodiment, the area where the wall portion 35 is connected to the hub 22 is smaller than in the bottom flange-equipped hub member 110 of the first comparative example, in which the second inclined surface 35A is not formed on the wall portion 35. Therefore, in the bottom flange-equipped hub member 100 of this embodiment, when the resin shrinks during injection molding, the wall portion 35 acts as less resistance to the shrinkage of the hub 22 than in the bottom flange-equipped hub member 110 of the first comparative example. Therefore, in the bottom flange-equipped hub member 100 of the first embodiment, the roundness of the hub 22 is improved compared to the bottom flange-equipped hub member 110 of the first comparative example, as shown in FIG. 6 .

[0063] In addition, compared to the lower flanged hub member 110 of the first comparative example in which the second inclined surface 35A is not formed on the wall portion 35, in order to reduce the resistance effect of the wall portion 35 against the shrinkage of the hub 22 when the resin shrinks during injection molding, the inclination angle θ2 of the second inclined surface 35A may be in a range greater than 0 degrees and smaller than the inclination angle θ1 of the first inclined surface 33B.

[0064] In this embodiment, the ratio of the inclination angle θ2 of the second inclined surface 35A to the inclination angle θ1 of the first inclined surface 33B is, for example, 0.03 or more and 0.50 or less. When the ratio of the inclination angle θ2 to the inclination angle θ1 is 0.50 or less, the height of the second inclined surface 35A from the first inclined surface 33B can be ensured, compared to when the ratio exceeds 0.50, and the effect of preventing foreign matter from entering the inside of the hub 22 can be more effectively exhibited. Furthermore, when the ratio of the inclination angle θ2 to the inclination angle θ1 is 0.03 or more, compared to when the ratio is less than 0.03, the portion where the wall portion 35 is formed is prevented from bulging outward in the radial direction when the resin shrinks during injection molding, and a hub 22 with improved roundness can be obtained.

[0065] In this embodiment, a tapered surface 37 is formed on the opening edge of each through hole 29 on the second inclined surface 35A side. When each leg portion 94 of the release member 90 inserted into the through hole 29 from the second inclined surface 35A side comes into contact with the tapered surface 37, the tapered surface 37 guides the leg portion 94 toward the center of the through hole 29.

[0066] In this embodiment, since a plurality of through holes 29 are formed, a structure can be realized in which a plurality of leg portions 94 of the release member 90 are inserted into each of the through holes 29, respectively.

[0067] The wall portions 35 are erected on both circumferential sides of each through hole 29. Therefore, foreign matter can be prevented from passing through the through hole 29 and entering the inside of the hub 22 on both circumferential sides of each through hole 29.

[0068] The technology of the present disclosure provides a tape reel 20 having a hub 22 with a roundness of 30 μm or less. This roundness is defined as (Dmax-Dmin) / 2, where Dmax is the maximum diameter of the hub 22 and Dmin is the minimum diameter. The roundness of the hub 22 according to the technology of the present disclosure satisfies the above-mentioned roundness condition on both the base end side and the tip end side.

[0069] In the tape reel 20 according to the technology of the present disclosure, the recording tape T is wound around the hub 22. Then, inside the drive device, the recording tape T is unwound from the tape cartridge 10. In this case, by having the roundness of the hub 22 be 30 μm or less, it is possible to suppress fluctuations in the feed speed of the recording tape T and bring the feed speed closer to a constant speed, compared to when the roundness exceeds 30 μm. Because fluctuations in the feed speed of the recording tape T are suppressed, errors in reading and writing information from and to the recording tape T can also be suppressed.

[0070] To determine the shape of the mold for actually molding the lower flanged hub member 100, the following method can be used as an example.

[0071] That is, first, a lower flanged hub member is formed using a mold for molding a lower flanged hub member in which the second inclined surface 35A is not formed and the upper surface of the wall portion 35 is flush with the central surface 33A (not inclined relative to the central surface 33A of the bottom wall 28).

[0072] The shape of the formed hub member with a bottom flange is then measured, and the shape of the mold is modified based on the measurement results. Specifically, the inclination angle θ2 of the second inclined surface 35A is set and the mold is modified. The modified mold is then used to form the hub member with a bottom flange again. By repeating this process, the inclination angle θ2 of the second inclined surface 35A is determined, and the shape of the hub of the formed hub member with a bottom flange can be made closer to a perfect circle. Therefore, no lower limit for circularity is specified for the hub 22 according to the technology disclosed herein.

[0073] The material of the lower flange-equipped hub member 100 according to the technology of the present disclosure is not particularly limited as long as it is resin. From the viewpoint of satisfying the strength and durability required of the tape reel 20, for example, glass fiber reinforced polycarbonate is preferable. The glass fiber content in the glass fiber reinforced polycarbonate is, for example, 10% or more and 30% or less.

[0074] In the description of this specification, "parallel" refers to parallelism in the sense of including a tolerance that is generally accepted in the technical field to which the technology of the present disclosure belongs, in addition to completely parallelism. In the description of this specification, "perpendicular" refers to perpendicularity in the sense of including a tolerance that is generally accepted in the technical field to which the technology of the present disclosure belongs, in addition to completely perpendicularity. In the description of this specification, "equally spaced" refers to equidistant spacing in the sense of including a tolerance that is generally accepted in the technical field to which the technology of the present disclosure belongs, in addition to completely equal spacing. In the description of this specification, "matched" refers to matching in the sense of including a tolerance that is generally accepted in the technical field to which the technology of the present disclosure belongs, in addition to completely equal spacing.

[0075] The above-described description and illustrations are a detailed explanation of the parts related to the technology of the present disclosure and are merely an example of the technology of the present disclosure. For example, the above description of the configuration, functions, actions, and effects is an explanation of an example of the configuration, functions, actions, and effects of the parts related to the technology of the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or replacements may be made to the above-described description and illustrations within the scope of the gist of the technology of the present disclosure. Furthermore, to avoid confusion and facilitate understanding of the parts related to the technology of the present disclosure, the above-described description and illustrations omit explanations of common technical knowledge that do not require particular explanation to enable the implementation of the technology of the present disclosure.

[0076] In this specification, "A and / or B" is synonymous with "at least one of A and B." In other words, "A and / or B" means that it may be only A, only B, or a combination of A and B. Furthermore, in this specification, the same concept as "A and / or B" is also applied when three or more things are expressed connected by "and / or."

[0077] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference. [Explanation of symbols]

[0078] 10 Tape Cartridge 12 cases 14 Upper case 16 Lower case 20 tape reels 22 Hub (an example of a cylindrical part) 28 Bottom wall (example of bottom) 29 Through holes 33 Top surface (example of vertical surface) 33A Center plane 33B 1st slope 35 Wall 35A 2nd slope 37 Tapered surface 100 Lower flanged hub member θ1 Inclination angle of the first inclined plane θ2 Inclination angle of the second inclined surface T Recording tape (an example of tape)

Claims

1. A cylindrical portion; a bottom portion having an upright surface on which the cylindrical portion stands; Equipped with The erection surface is a central surface located on the central side of the bottom portion; a first inclined surface formed on an outer periphery of the central surface along the circumferential direction of the cylindrical portion, the first inclined surface being inclined so that the thickness of the bottom portion gradually decreases toward the outer periphery; and a through hole penetrating the bottom portion is formed in the outer periphery; a pair of wall portions are provided on the first inclined surface on both sides of the through hole in the circumferential direction; A second inclined surface is formed on a surface of each of the walls that is continuous with the central surface, and the inclination angle of the second inclined surface relative to the central surface is smaller than the inclination angle of the first inclined surface. Tape reel.

2. The ratio of the inclination angle of the second inclined surface to the inclination angle of the first inclined surface is 0.03 or more and 0.50 or less.

2. The tape reel according to claim 1.

3. a tapered surface formed on an opening edge of the through hole on the second inclined surface side and diverging toward the second inclined surface side; 3. The tape reel according to claim 1 or 2.

4. A plurality of the through holes are formed at intervals in the circumferential direction, The wall portions are provided on both sides of the through hole in the circumferential direction. The tape reel according to any one of claims 1 to 3.

5. The tape reel according to any one of claims 1 to 4; a case that rotatably supports the tape reel and accommodates the tape reel and a tape wound around the tape reel; A tape cartridge having:

Images