JPS5822308Y2 - tape reel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape reel, and particularly to a reel suitable for use in tape cassettes for winding and storing magnetic tape in VTRs, tape recorders, etc.

A tape cassette used in a cassette type VTR generally has a pair of reels housed in a cassette casing, and a magnetic tape is wound around each reel with both ends fixedly attached.

Flanges are provided at both ends of the reel to prevent the magnetic tape from moving in the width direction of the reel.

In this case, it is desirable that the flange be configured to be large enough to still come into contact with the outermost magnetic tape even when all of the magnetic tape is wound onto one reel.

However, in this case, the distance between the pair of reels increases, and the tape cassette becomes larger accordingly.

Therefore, as shown in FIG. 1, one of the reels 12 and 13 in the casing 11 has a main flange 14 with a large diameter at its lower end, and an auxiliary flange 15 with a relatively small diameter at its upper end. Form each and also reel 1
In contrast, a tape cassette has been proposed in which a large main flange 14 is formed at the upper end and a small auxiliary flange 15 is formed at the lower end.

According to such a configuration, the pair of reels 12 and 13 can be brought close to each other, so that the tape cassette can be made smaller.

Both the main flange 14 and the auxiliary flange 15 are circular, and the diameter of the main flange 14 is larger than the diameter of the auxiliary flange 15, and the diameter of the auxiliary flange 15 is also larger than the diameter of the reel hub 16.

Therefore, in order to integrally mold these reels 12 and 13 from synthetic resin, it is necessary to use a split mold, which makes the mold complicated (cutting the mold becomes troublesome as well).

Therefore, in the past, the reel hub 16 and one flange, for example, the main flange 14, were integrally molded, and the other auxiliary flange 15 was joined to the end of the reel hub 16 by ultrasonic welding as shown in FIG. Ta.

However, this type of connection adds a welding process to the tape reel manufacturing process, making the process complicated.

Further, it is necessary to provide a welding margin with high accuracy on one of the reel hub 16 and the auxiliary flange 15, and furthermore, the dimensional accuracy of the tape reel 12 in the axial direction tends to vary depending on the welding conditions.

In addition, the heat applied during welding causes the reel hub 16 to
deforms, thereby causing the magnetic tape 17 being wound.
There were problems such as negative effects on the

It is also considered to eliminate the auxiliary flange 15 in order to integrally mold the tape reel 12, but if this is done, there is a problem that the magnetic tape IT will become uneven when winding the magnetic tape 17 around one reel hub. There is,
Furthermore, if the opening 18 formed in the cassette casing 11 for inserting the reel shaft for driving the tape reel 12 is large, at least the hub 16 of the tape reel 12 will fall out of the opening 18. A problem arises.

The present invention was developed in view of these problems, and includes a main flange provided at one end of the reel hub, and
In the reel in which an auxiliary flange smaller than the main flange is provided at the other end, the auxiliary flange is formed from segments partially formed in the circumferential direction of the reel hub, and at least the segments are formed on the main flange. This relates to a tape reel characterized in that openings of the same size are formed at positions corresponding to the segments.

Therefore, according to the present invention, it is possible to integrally mold the main flange and the auxiliary flange together with the reel hub without using split molds, thereby improving the dimensional accuracy of the tape reel and reducing costs.

An embodiment in which the present invention is applied to a reel of a tape cassette used in a cassette type VTR will be described below with reference to the drawings.

As shown in FIGS. 3 and 4, the tape reel 20 of this embodiment is integrally molded from synthetic resin, and a main flange 22 having a relatively large diameter is provided at the lower end of the reel hub 21. ing.

Also, at the upper end of this reel hub 21 there is a pair of segment) 2
3.24 is provided.

These segments) 23 and 24 are provided symmetrically with respect to the axis of the reel hub 21, and
They are each formed into a fan shape occupying a suitable angle, for example, 600 degrees, in the circumferential direction.

These segments 23 , 24 also have a diameter smaller than the diameter of the main flange 22 .

These segments 23, 24 constitute the auxiliary flanges of the tape reel 20.

In the main flange 22, fan-shaped openings 25 and 26 having the same size as these segments 23 and 24 are formed at positions corresponding to these segments t-23 and t-24, respectively.

The reel hub 21 has a cylindrical shape, and a magnetic tape is wound around the outer peripheral surface of the reel hub 21.

Further, a recess 27 is formed inside the reel hub 21 to receive the reel shaft.

The upper end of this recess 27 is closed by a rib 28.

Note that the segments 23 and 24 are located at positions where the ribs 28 are extended radially outward.

The rib 28 has a positioning hole 2 for the reel shaft in its center.
9 is formed, and furthermore, three engagement holes 30 are formed on the outside of this positioning hole 29.

These engagement holes 30 engage with pins provided at the upper end of the reel shaft, thereby allowing the tape reel 20 to be rotationally driven by the reel shaft.

Next, we will discuss the molding of the tape reel 20 having such a configuration. As shown in FIG. This results in one-shot integral molding.

That is, the lower mold 32 is provided with a pair of protrusions 33 and 34 having a sector-shaped cross section, and these protrusions 33
．． Segment 23 forming an auxiliary flange by 34
．． 24 is formed integrally with the rim 20.

These protrusions 33, 34 simultaneously form a pair of fan-shaped openings 25, 26 in the main flange 22.

Furthermore, a cylindrical protrusion 35 is provided on the lower mold 32, and the recess 27 is formed by this protrusion 35.

A positioning hole 29 is further provided at the upper end of the protrusion 35 of the mold 32.
A small cylindrical projection 36 for forming the engagement hole 30 is formed in the mold 31, and a cylindrical projection 31 for forming the engagement hole 30 is formed in the mold 31.

Thus, the main flange 22 has segments 23, 24
By providing the openings 25 and 26 of the same shape at the corresponding positions, it is possible to
The main flange 22 is formed only by a pair of upper and lower molds 31°32.
and an auxiliary flange 23,24.
This makes it possible to mold them in one shot.

Therefore, the manufacturing process of the tape reel 20 is streamlined and costs can be reduced.

Further, since the auxiliary flange is not welded, dimensional variations and thermal deformation caused by welding are effectively prevented.

The tape reel 20 described with reference to FIGS. 3 and 4 is the supply reel of a pair of reels used in a VTR cassette, but the take-up reel can also be integrally molded in the same way. can.

FIG. 6 shows another embodiment of the present invention, and this embodiment concerns a reel 40 on the winding side.

In the take-up reel 40, the main flange 41 is disposed upward within the cassette casing.
The rib 42 is also arranged on the upper end surface of the reel hub 43, that is, on the main flange 41 side.

Openings 47 are formed in the main flange 41 in correspondence with the segments 4546 that constitute the auxiliary flange.
．． 48 is constructed much larger than these segments 45.46.

One of these openings 47 and 48 is also used for inserting the locking piece 50 into an engagement groove 49 formed on the outer peripheral surface of the reel hub 43.

The locking piece 50 is for securing one end of the magnetic tape 51 to the outer circumference of the reel hub 43.

Although the present invention has been described above with reference to embodiments, the present invention is not limited to the above embodiments, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiment, two segments are provided to constitute the auxiliary flange, but the number of segments may be one, or three or more.

As described above, the present invention consists of an auxiliary flange consisting of segments partially formed in the circumferential direction of the reel hub, and an opening at least the same size as the segment in the main flange at a position corresponding to the segment. Since the tape reel has a main flange and an auxiliary flange, it is possible to integrally mold the tape reel with a synthetic resin without using a split mold, and the manufacturing of the tape reel is greatly streamlined.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a tape cassette containing a conventional tape reel, Fig. 2 is a longitudinal sectional view of the tape reel showing the assembled state of the tape reel, and Fig. 3 is a longitudinal sectional view of a tape cassette containing a conventional tape reel.
FIG. 4 is a longitudinal sectional view of the tape reel showing the embodiment of the present invention, FIG. 5 is a longitudinal sectional view of the mold showing the state of molding of this tape reel, and FIG. It is a perspective view of the tape reel of an Example. In addition, in the symbols used in the drawings, 20... tape reel, 21... reel hub, 22...
...Main flange, 23...Segment, 24.
...segment, 25 ... sector-shaped opening,
26...Fan-shaped opening○

Claims (1)

[Scope of utility model registration request] In a reel having a main flange at one end of a reel hub and an auxiliary flange smaller than the main flange at the other end, the auxiliary flange is composed of segments partially formed in the circumferential direction of the reel hub. The tape reel is further characterized in that the main flange is formed with an opening having at least the same size as the segment at a position corresponding to the segment.