JPH087972B2 - Tape reel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a tape reel suitable for being applied to a tape cassette.

[0002]

2. Description of the Related Art The structure of a conventional tape reel hub will be described below with reference to FIGS. Figure 5A
6A, reference numeral 1 denotes a hub as a whole, each of which is cylindrical and has a coaxial outermost hub portion 1a, a middle hub portion 1b, and an innermost hub portion 1c. Each hub part 1
A plurality of ribs 2a and 2b are arranged in the gaps between a, 1b and 1c at regular angular intervals. Outermost hub part 1
a is a tape winding section, and a tape clamper 4
Is provided. An inner side of the innermost hub portion 1c is an engagement hole for a reel shaft of a magnetic recording / reproducing apparatus such as a VTR,
A plurality of claws 3a arranged at predetermined angular intervals are provided. Although not shown, the hub 1 is arranged at the center of a disc-shaped flange and is integrally formed with the flange by using a plastic material.

In the hub 1 of FIG. 5A, ribs 2a, 2
b is arranged on the same radiation, and the claw 3a is arranged on the radiation intermediate between the ribs 2a and 2b. Further, in the hub 1 of FIG. 6A, the ribs 2a and 2b and the claw 3a are all arranged on the same radiation.

[0004]

By the way, when the tape is wound around the hub 1, the hub 1 receives a force in the axial direction, and when the winding amount of the tape increases, the hub 1 shown in FIGS. 5A and 6A.
As shown in FIGS. 5B and 6B, respectively,
1b and 1c are deformed into concave or convex in the radial direction.

However, in the hub 1 of FIGS. 5A and 6B, since the ribs 2a and 2b arranged in the gaps between the hub portions 1a, 1b and 1c are arranged on the same radiation, the tape winding is performed. When the loading amount is considerably large, the axial force applied to the outermost hub portion 1a by the tape winding is strongly transmitted to the innermost rib portion 1c via the ribs 2a and 2b. The joint hole 3 is considerably reduced and deformed, which makes it difficult to insert and remove the reel shaft into and from the engaging hole.

In view of the above point, the present invention is intended to propose a tape reel capable of reducing the degree of contraction deformation of the engagement hole with respect to the reel shaft due to the tape winding around the hub.

[0007]

The present invention provides a flange 5
And a hub 1 provided at the center of the flange 5, the hub 1 having N (≧ 3) coaxial hub portions 1a to 1a.
1c and a plurality of ribs 2a arranged in the respective gaps,
In the tape reel comprising 2b and the engaging hole 3 for the reel shaft provided in the innermost hub portion 1c of the N hub portions 1a to 1c, the N hub portions 1a
1a, 1b adjacent to each gap of 1c; 1b, 1c
The relative positions of the plurality of ribs 2a and 2b provided on each other are made different.

[0008]

According to the present invention, when the hub 1 is applied with a force toward the axial center by the tape winding, the displacement of each of the plurality of ribs 2a and 2b toward the axial center is caused by the rib portion 1 respectively.
The deformation of b and 1c is considerably absorbed, and the degree of reduction and deformation of the engagement hole 3 with respect to the reel shaft due to the tape winding around the hub 1 is reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a tape cassette of a digital VTR will be described in detail below with reference to FIGS. First, the structure of the tape reel will be described with reference to FIGS. 1 and 2. In FIGS. 1 and 2, the parts corresponding to those of FIGS. 5 and 6 are designated by the same reference numerals. Reference numeral 1 denotes a hub as a whole, which is erected at the center of a disk-shaped flange 5 having teeth 5a formed on the outer circumference and is integrally molded together with the flange 5 using a plastic material. Further, another disc-shaped flange 6 is fixed to the free end of the hub 1, and the both flanges 5 and 6 are opposed to each other substantially parallel to each other via the hub 1.

The hubs 1 are arranged coaxially with each other, and are placed at 60 ° in a gap between the cylindrical outermost peripheral hub portion 1a, intermediate peripheral hub portion 1b and innermost peripheral hub portion 1c, and the hub portions 1a and 1b. Of the plate-shaped cylinder 2 and the six ribs 2a arranged in the gap between the six plate-shaped ribs 2a and the hub portions 1b, 1c arranged at 60 ° intervals, and the innermost hub portion 1c. It is integrally configured with an engaging hole 3 for the reel shaft, which has 12 claws 3a provided inside and arranged at intervals of 30 °. In this case, the height of the hub portion 1a is larger than that of the hub portions 1b and 1c.

The rib 2b is provided so as to correspond to the intermediate position between the adjacent ribs 2a and the midpoint position of the adjacent claw 3a.

Reference numeral 7 denotes a cylindrical reel shaft of a VTR, and three claws 7a are provided at 120 ° intervals on the peripheral surface of the VTR, and are integrally formed at the center of a disk-shaped reel stand 8 for supporting a tape reel. Have been planted.

A circular protrusion 6a is formed in the center of the other flange 6, and the protrusion 6a is supported by the hubs 1b and 1c of the hub 1 and is formed in the protrusion 6a . The rib 2b is fitted in the hole, and the flange 6 is attached to the hub 1 by adhesion or welding between the protrusion 6a and the top of the rib 2b. Further, the peripheral portion of the protruding portion 6a of the flange 6 abuts against and is supported by the hub portion 1a.

Incidentally, the diameters of the flanges 5 and 6 are 178.
5 mm, outer diameter of outermost hub portion 1a is 58 mm, engagement hole 3
Has an inner diameter of 32 mm.

Next, the operation of this tape reel will be described. A large amount of tape is wound around the hub portion 1a of the hub 1,
When a force is applied toward the axis X, the intermediate portion of the hub portion 1a with respect to the rib 2a is recessed toward the axis X, and the rib 2a is displaced toward the axis X. Then, the hub portion 1b,
The middle portion of the rib 2b is recessed toward the axis X, and the rib 2
b is displaced toward the axis X. Thus, the hub portion 1c
However, the vicinity of the portion corresponding to the rib 2b is recessed toward the axis X, and the entire hub portion 1c is contracted and deformed, but the extent thereof is slight. Further, if the number of hub portions is increased, the extent of the contraction deformation of the engagement hole of the innermost peripheral hub portion with respect to the reel shaft is correspondingly increased.
It will be even smaller.

FIGS. 3 and 4 show a large-sized tape cassette for a digital VTR using the above-mentioned tape reel. Reference numeral 10 denotes a tape reel for supplying and winding, and T
Indicates a magnetic tape wound around these reels 10. FIG. 3 shows a state in which the tape reel 10 is arranged on the lower half 12 of the housing 11 of the tape cassette shown in FIG. Thirteen
Is a claw for preventing the rotation of the tape reel when the tape cassette is not used, and engages with teeth formed on the outer periphery of the flange 5 of the tape reel.

Incidentally, the flange 6 of the tape reel can be omitted.

[0018]

According to the present invention described above, it is possible to reduce the degree of contraction deformation of the engagement hole with respect to the reel shaft due to the tape winding around the hub. Therefore, there is almost no possibility that it is difficult to insert and remove the reel shaft into and from the engagement hole. Therefore, on a large tape reel with the above-mentioned exemplary dimensions,
It is very effective when winding a large amount of tape.

[Brief description of drawings]

FIG. 1 is a plan view showing a part of a tape reel according to the present invention.

FIG. 2 is a sectional view of a tape reel according to the present invention.

FIG. 3 is a plan view showing a lower half of a tape cassette including the tape reels of FIGS. 1 and 2.

FIG. 4 is a side view of the tape cassette.

FIG. 5 is a plan view showing a structure of a hub of a conventional tape reel and a modified state thereof.

FIG. 6 is a plan view showing a structure of a conventional tape reel hub and a modified state thereof.

[Explanation of symbols]

 1 hub 1a-1c hub part 2a, 2b rib 3 engagement hole for reel shaft 5,6 flange

Claims (1)

[Claims] 1. A flange, and a hub provided at the center of the flange, the hub being N (≧ 3) hubs having a coaxial center, and a plurality of hubs respectively arranged in the respective gaps. Ribs,
Provided on the innermost hub portion of the N hub portions,
In a tape reel composed of an engagement hole for a reel shaft, the relative positions of a plurality of ribs provided in adjacent ones of the gaps of the N hub portions are made different from each other. Tape reel characterized by.