JPH10149660A - Tape reel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the scattering of resin powders by a projecting stepped part which is provided on the mounting part of a reel plate, and to enable the prevention of deterioration in the property of a magnetic tape such as dropout, etc., at the time of recording/reproducing operation, even though the resin is scraped and the powders are fallen down due to the burr of the reel plate. SOLUTION: The projecting stepped part 15 for preventing the scattering of resin powders is provided on all around the outermost peripheral part at the mounting part 11 of reel plate on the lower side reel member 7 of a tape cassette for VTR. By forming such a structure, the resin powders become the state sealed into the space between the reel plate 1O and the mounting part 11 of reel plate by the stepped part 15 even though the resin is scraped and the powders are fallen down due to the burr 10a of the reel plate 10, therefore, the resin powders are not scattered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape reel incorporated in, for example, a tape cassette for a VTR, and more particularly to a tape reel formed by integrally fixing a resin upper reel member and a lower reel member. The present invention relates to a tape reel in which a metal reel plate is mounted so as to be sandwiched between an upper reel member and a lower reel member.

[0002]

2. Description of the Related Art First, a conventional example will be described with reference to FIGS.

In FIGS. 1 and 2, reference numeral 1 denotes a VTR tape cassette, 2 denotes a cassette housing thereof, and the cassette housing 2 is provided with a magnetic tape corresponding to a reel drive shaft insertion hole 3 formed at the bottom. A pair of tape reels (a take-up reel and a supply reel) 5 around which the tape 4 is wound are rotatably accommodated.

[0004] As shown in FIG.
In each case, the upper reel member 6 and the lower reel member 7 made of resin are united and fixed.

[0005] The upper reel member 6 constitutes an upper flange of the tape reel 5, and has a hole 6a formed at a center portion thereof, through which a later-described reel plate projects. On the other hand, the lower reel member 7 integrally has a flange portion 7a constituting a lower flange of the tape reel 5, a hub portion 7b around which the magnetic tape 4 is wound, and a central cylindrical portion 7c inside the hub portion 7b. A plurality of engaging claws 8 are formed on the inner peripheral surface of the central cylindrical portion 7c to engage with the reel drive shaft of the cassette deck.

A welding rib 9 is provided on the upper end surface of the central cylindrical portion 7c. The welding rib 9 is placed in a state where the upper reel member 6 is placed on the central cylindrical portion 7c of the lower reel member 7.
By applying ultrasonic waves to the upper reel member 6
And the lower reel member 7 are welded and united and fixed.

Further, at the center of the tape reel 5,
A metal reel plate 10 separate from the upper reel member 6 and the lower reel member 7 is attached.

The reel plate 10 is machined so as to protrude at the center thereof into a spherical shape, and is mounted so as to be sandwiched between the upper reel member 6 and the lower reel member 7. That is, a concave step-shaped reel plate attaching portion 11 is formed over the entire periphery at the upper end of the central cylindrical portion 7c of the lower reel member 7, and the reel plate 10 is fitted into the reel plate attaching portion 11. The upper reel member 6 and the lower reel member 7 are united and fixed by ultrasonic welding.

In the reel plate 10 mounted in such a manner as to be sandwiched between the upper reel member 6 and the lower reel member 7, the spherical portion at the center thereof has a hole at the center of the upper reel member 6. 6a protrudes from the upper surface of the tape reel 5.

The reel plate 10 of the tape reel 5
The reel holder 12 is attached to the upper surface of the cassette housing 2 in correspondence with the above, and the reel holder 12 elastically presses the center of the reel plate 10 by the force of the spring 13 to always hold the tape reel 5. It is pressed against the bottom of the cassette housing 2 (playback is prevented).

When the tape cassette 1 constructed as described above is mounted on the cassette deck, the reel drive shaft on the cassette deck side is inserted from the insertion hole 3 and engages with the engaging claw 8 of the tape reel 5. When the reel drive shaft is rotated by the motor in this state, the tape reel 5 rotates integrally with the shaft and the magnetic tape 4 runs.
At this time, the tape reel 5 is rotated while being lifted from the bottom of the cassette housing 2.

The reel plate 10 attached to the center of the tape reel 5 in the tape cassette 1 is formed by stamping a sheet metal material by a press, so that its outer peripheral edge is formed as shown in FIG. Burrs 10a occur.

The reel plate 10 is provided with the burr 1
The lower reel member 7 is mounted on the reel plate mounting portion 11 with the surface on which 0a protrudes downward.
This is because the burr 10a is hooked on the lower reel member 7 which is engaged with the reel drive shaft of the cassette deck, thereby placing a burden on the welded portion between the upper reel member 6 and the lower reel member 7. The reason is that the reel plate 10 is rotated integrally with the tape reel 5.

[0014]

However, the burr 10a of the reel plate 10 rubs against the reel plate mounting portion 11 of the lower reel member 7 due to the vibration of the ultrasonic welding when the tape reel 5 is assembled. Part of the resin is shaved, causing so-called powder dropping as shown in FIG.

The resin powder 14 removed by the burr
Is difficult to blow out to the upper surface side of the reel plate 10 (because the upper surface side of the reel plate 10 is widely covered by the upper reel member 6), but the lower reel side of the lower surface side of the reel plate 10 as shown in the drawing. The air blows toward the inner surface of the central cylindrical portion 7 c of the member 7 and scatters, and adheres to the reel plate 10.

The resin powder 14 is supplied to the tape reel 5
If the particles are scattered during the rotation of the tape and are caught between the magnetic tapes, adverse effects such as signal dropout during recording and reproduction are caused.

In order to eliminate the problem of powder dropping, a method of removing burrs 10a generated on the reel plate 10 by barrel polishing or the like can be considered, but it is not easy to completely remove burrs. It is not practical because the cost will increase significantly.

The present invention has been made in view of the above problems, and has a problem to be solved in that it is possible to simply and surely prevent the harmful effects such as the draw-out due to resin powder dropping. .

[0019]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is configured such that an upper reel member and a lower reel member made of resin are united and fixed, and a metal part is formed at a center portion. In a tape reel in which a reel plate is mounted so as to be sandwiched between an upper reel member and a lower reel member, a resin shaved by a burr generated at an edge of the reel plate is attached to a mounting portion of the reel plate. A convex step is provided to prevent scattering of the powder.

With such a structure, the resin powder shaved by the burr of the reel plate is in a state of being confined by the stepped portion, so that the resin powder is scattered and caught in the magnetic tape. Therefore, it is possible to reliably prevent deterioration of the magnetic tape characteristics such as dropout during recording and reproduction.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. In this embodiment, the VTR tape cassette described in the conventional example of FIGS. 1 to 4 will be described as an example.

In FIGS. 1 and 2, reference numeral 1 denotes a VTR tape cassette, 2 denotes a cassette housing thereof, and the cassette housing 2 has a magnetic recording disk corresponding to a reel drive shaft insertion hole 3 formed at the bottom. A pair of tape reels (a take-up reel and a supply reel) 5 around which the tape 4 is wound are rotatably accommodated.

This tape reel 5 is, as shown in FIG.
In each case, the upper reel member 6 and the lower reel member 7 made of resin are united and fixed.

The upper reel member 6 constitutes an upper flange of the tape reel 5, and has a hole 6a in the center thereof through which a later-described reel plate projects. On the other hand, the lower reel member 7 integrally has a flange portion 7a constituting a lower flange of the tape reel 5, a hub portion 7b around which the magnetic tape 4 is wound, and a central cylindrical portion 7c inside the hub portion 7b. A plurality of engaging claws 8 are formed on the inner peripheral surface of the central cylindrical portion 7c to engage with the reel drive shaft of the cassette deck.

A welding rib 9 is provided on the upper end surface of the center tube portion 7c, and the upper rib member 6 is placed on the center tube portion 7c of the lower reel member 7 in a state where the welding rib 9 is placed.
By applying ultrasonic waves to the upper reel member 6
And the lower reel member 7 are welded and united and fixed.

Further, at the center of the tape reel 5,
A metal reel plate 10 separate from the upper reel member 6 and the lower reel member 7 is attached.

The reel plate 10 is machined so as to have a central portion protruding in a spherical shape, and is mounted so as to be sandwiched between the upper reel member 6 and the lower reel member 7. That is, a concave step-shaped reel plate attaching portion 11 is formed over the entire periphery at the upper end of the central cylindrical portion 7c of the lower reel member 7, and the reel plate 10 is fitted into the reel plate attaching portion 11. The upper reel member 6 and the lower reel member 7 are united and fixed by ultrasonic welding.

The reel plate 10 mounted in such a manner as to be sandwiched between the upper reel member 6 and the lower reel member 7 has a spherical portion at a central portion thereof having a hole at a central portion of the upper reel member 6. 6a protrudes from the upper surface of the tape reel 5.

The reel plate 10 of the tape reel 5
The reel holder 12 is attached to the upper surface of the cassette housing 2 in correspondence with the above, and the reel holder 12 elastically presses the center of the reel plate 10 by the force of the spring 13 to always hold the tape reel 5. It is pressed against the bottom side of the cassette housing 2.

In the tape cassette 1 configured as described above, the reel plate 10 attached to the center of the tape reel 5 is formed by stamping a sheet metal material by a press. As shown in FIG. 4, burrs 10a are generated.

The reel plate 10 is provided with the burr 1
The lower reel member 7 is mounted on the reel plate mounting portion 11 with the surface on which 0a protrudes downward.

In this case, as described above, the tape reel 5
Reel plate 1 by vibration of ultrasonic welding when assembling
There is a problem that the burrs 10a of 0 scrape off the resin of the reel plate attaching portion 11 to cause powder drop.

Therefore, in this embodiment, as shown in FIG. 6, a convex step portion 15 for preventing resin powder from being scattered is entirely provided on the innermost peripheral portion of the reel plate mounting portion 11 of the lower reel member 7. It is provided over the circumference.

That is, with this structure, even if the resin is shaved by the burr 10a of the reel plate 10 and powder falls off, the resin powder can be removed by the step 15 between the reel plate 10 and the reel plate attaching portion. The resin powder is not scattered since it is sealed in the space between the resin powder and the resin powder.

Here, the projection height a of the step 15 is substantially the same as or larger than the projection height b of the burr 10a, taking into account the projection height b of the burr 10a of the reel plate 10. 0.05 to 0.1 mm. However, even if the burr 10a is higher than this height, the scattering of the resin powder can be sufficiently suppressed by the step portion 15.

In this structure, the step 15 is also a portion where the reel plate 10 is actually held.
It must be formed with a proper width shape. Even if the width dimension c of the step portion 15 is about 0.1 mm, it functions sufficiently to prevent scattering of resin powder. However, in order to properly form the width shape of the step portion 15 by resin molding (injection molding), it is necessary to use the step c. The width c of the portion 15 is set to 0.3 mm or more.

By setting the width c of the step portion 15 to 0.3 mm or more, even if the tape cassette falls and a large drop load is applied to the reel plate 10, it is sufficient for the drop load. High strength can be maintained, that is, the step 15 does not collapse due to the drop of the tape cassette.

Although the embodiment of the present invention has been described above, the present invention is, of course, not limited to this embodiment.

[0039]

As is apparent from the above description, in the tape reel of the present invention, since the convex step portion is provided in the mounting portion of the reel plate, the resin is shaved by the burr of the reel plate, and powder drop occurs. Even so, the step can effectively prevent the resin powder from scattering,
There is no possibility that the resin powder is caught in the magnetic tape, so that it is possible to reliably prevent the magnetic tape characteristics such as dropout during recording and reproduction from deteriorating. The present invention is structurally simple and can be easily implemented.

[Brief description of the drawings]

FIG. 1 is a perspective view of a tape cassette viewed from below.

FIG. 2 is a longitudinal sectional view of the same.

FIG. 3 is an exploded longitudinal sectional view of the tape reel.

FIG. 4 is a longitudinal sectional view of a reel plate.

FIG. 5 is an enlarged view of a mounting portion of a reel plate on a tape reel.

FIG. 6 is an enlarged view of a mounting portion of a reel plate in the tape reel according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram of dimensions of a step portion.

[Explanation of symbols]

1 ‥‥ tape cassette, 5 ‥‥ tape reel, 6 ‥‥ upper reel member, 7 ‥‥ lower reel member, 10 ‥‥ reel plate, 10a ‥‥ burr, 11 ‥‥ reel plate mounting part, 15 ‥‥ step Department

Claims (3)

[Claims] An upper reel member and a lower reel member made of resin are united and fixed together, and a metal reel plate is sandwiched between the upper reel member and the lower reel member at the center. In the tape reel which is mounted in a state in which the reel plate is mounted, a convex step portion for preventing scattering of resin powder shaved by burrs generated on the edge of the reel plate is provided on a mounting portion of the reel plate. A tape reel characterized by being provided. 2. The projection height of said step portion is 0.05-0.
The tape reel according to claim 1, wherein the tape reel is 1 mm. 3. The tape reel according to claim 1, wherein the width of the step is 0.3 mm or more.