JPS5919979Y2 - Screwed structure of cassette case - Google Patents

Description

[Detailed description of the invention] The present invention relates to a screw-fastening structure for a cassette case, and in particular, in a case where the two upper and lower outer casings forming the cassette case are fixed with tapping screws, the two outer casings are provided with tapping screws. It relates to screw holes with symmetrical shapes.

The cassette is constructed by winding magnetic tape around an internal bubble, covering it with two upper and lower outer casings, and crimping these two outer casings together.This prevents dust from entering the cassette case. This prevents easy intrusion and prevents the magnetic tape from being soiled.

In response to this, conventional methods have been provided in which the peripheral edges of the outer casings are fixed to each other with an adhesive in order to reliably press the two upper and lower casings together.

However, in such a cassette case, it is necessary to work to release the magnetic tape from being entangled in the capstan, etc., which occurs when the tape is used for a long period of time, to adjust the pressure spring of the pad against the magnetic head, and to wind the magnetic tape onto the Nordbub. This made it impossible to create optical illusions of the loaded state, and there was a risk of damaging the cassette case if the cassette case was forcibly opened.

In addition, in order to facilitate the attachment and detachment of the cassette case outer casing, a notch is provided on the peripheral edge of one of the outer casings, and a fitting protrusion is provided on the periphery of the other outer casing to be locked into the notch. There has been provided a device in which the outer casing is joined by aligning each of the above-mentioned peripheral markings.

However, in such a cassette case, when the upper and lower outer casings are repeatedly attached and detached, the above-mentioned notch gradually expands, the above-mentioned protrusion deforms, and the connection gradually becomes looser, until the outer casings are not connected. There are drawbacks that make it impossible.

On the other hand, in order to allow repeated attachment and detachment of the outer casing, a relatively large diameter hole is provided in the peripheral edge of one outer casing, and a hole with a smaller diameter than the above hole is provided in the periphery of the other outer casing. A cassette case is provided in which holes are provided, an out-of-plane case is joined so that these holes match, and a tapping screw is inserted through the large diameter hole and screwed into the small diameter hole. ing.

FIG. 1 is a partial cross-sectional view showing such a conventional cassette case, and FIG. 2 is a partially sectional view showing the coupling structure of the upper and lower outer casings of the cassette case.

In other words, in the same figure, 1 is a cassette case, and 2 are the upper and lower parts.
The upper outer casing 1a has two counterbore holes 2 for supporting screw heads and the through holes 3 that follow the counterbore holes 2 at the four corners of the upper outer casing 1a, while the through holes 3 of the lower outer casing 1b Through-holes 4 having a smaller diameter than the through-hole 3 are provided at the four corners corresponding to the above-mentioned through-holes.

When connecting the upper and lower outer casings 1a and 1b, use the tapping screws 5.
is inserted into the through hole 3, and the threaded part is forcibly screwed into the through hole 4 with a small diameter using a screwdriver or the like.
As shown in the figure, the out-of-plane casings 1a and lb are combined to form a cassette case.

However, in a cassette case with such a structure,
Upper and lower outer casings 1a.

Since the shapes of the through holes provided in 1b are different, the tapping screws 5 must always be screwed into the outer casings 1a and 1b from one side to the other, resulting in poor workability during assembly.

In particular, since there is always a play 6 between the through hole 3 and the tapping screw 5, the upper and lower outer casings 1a and lb may be displaced from each other during transportation or handling of the cassette case 1, and this displaced state When the tape stabilizes at , the magnetic tape cannot run smoothly in the linear direction. For example, if the upper edge of the magnetic tape receives strong tension and the lower edge becomes loose, a change appears in the pressure force against the magnetic head. If there is a difference in the input and output signal levels of the left and right channels, or if the magnetic tape begins to run at an angle to the head gap,
The phase characteristics of the input and output signals are shifted, and the reproduction sensitivity deteriorates particularly in the high frequency region, resulting in a situation similar to that in which the azimuth is out of order.

Particularly, such a phenomenon occurs conspicuously when debris generated when the tapping screw 5 is screwed in enters into the play 6.

The present invention was made to improve such conventional drawbacks, and in the case where the two upper and lower outer casings forming the cassette case are fixed with tapping screws, the screw holes etc. provided in these outer casings are made symmetrically. It is characterized by the fact that it facilitates the work of tightening screws and prevents displacement of the upper and lower outer casings, thereby stabilizing recording and playback characteristics.

Fig. 3 is a sectional view showing the screw fastening structure of the cassette case of the present invention. The outer casing 1a and the lower outer casing 1b are provided with counterbore holes 7, 8 for supporting screw heads, and counterbore holes 7, 8 for supporting screw heads.
Through holes 9 and 10 are provided symmetrically following 8, and these through holes 9 and 10 have a diameter somewhat smaller than the diameter of the tapping screw 11 so that the tapping screw 11 can be screwed into the through holes 9 and 10.

In addition, shallow holes 12.13 are provided in the abutting surfaces of the upper and lower outer casings 1a and lb of the through holes 9 and 10, and the tapping screws 1
The debris generated when screwing in 1 is trapped in these shallow holes 12 and 1.
It is designed to be housed within 3.

In a cassette case with such a structure, the upper and lower outer casings 1a
.

1b is formed symmetrically, and the tapping screw 1
1 are tightly fitted into the through holes 9, 10, so that displacement between the upper and lower outer casings 1a, 1b during transportation or the like is prevented.

Further, since the debris generated when the tapping screw 11 is screwed in is stored in the shallow holes 12 and 13, the debris does not intervene between the upper and lower outer casings and prevent the abutting surfaces from coming into close contact with each other. Displacement between the upper and lower outer casings due to uneven distribution within the holes 9 and 10 is prevented.

As described above, according to the present invention, in the screw-fastening structure of the cassette case in which the two upper and lower outer casings forming the cassette case are fixed with tapping screws, the tapping screws are installed in the mutually corresponding parts of the upper and lower two outer casings. A counterbore hole having an inner diameter into which a screw head can be inserted, and a through hole continuous with the counterbore hole and having an inner diameter slightly smaller than the threaded portion of the tapping screw are symmetrically provided, and the two upper and lower outer casings are A shallow hole is symmetrically provided on the outer periphery of the above-mentioned through-hole on the abutting surface to accommodate the debris generated when the tapping screw is screwed in, and the tapping screw can be screwed under the same conditions from either side of the two upper and lower outer casings. Because it is structured so that it can be screwed in, unlike conventional cassette cases where you always have to screw in the tapping screws from one side of the upper and lower outer casing to the other, you can check the top and bottom of the outer casing when screwing in, or if the screws are turned upside down. If there is, there is no need to turn it over, which can significantly improve work efficiency during assembly.

In addition, since the tapping screws fit tightly into the through holes of the two upper and lower outer casings, displacement between the two upper and lower outer casings during transportation is prevented, and debris generated during screwing is stored in the shallow holes. Therefore, debris will not interfere with the abutting surfaces of the upper and lower outer casings and prevent the upper and lower outer casings from being in close contact with each other, and furthermore, debris will not be unevenly distributed in the through holes and cause displacement between the upper and lower outer casings. Therefore, it has the advantage of being able to provide a cassette case with highly accurate and stable recording and playback characteristics.

[Brief Description of the Drawings] Fig. 1 is a perspective view of a conventional cassette case, Fig. 2 is a sectional view of the main part showing the connection structure of the upper and lower outer casings, and Fig. 3 is the upper and lower outer casings according to the present invention. FIG. 1... Cassette case, 1a... Upper outer casing, 1b.
...Lower outer casing, 7, 8...Spothole, 9,10...
Through hole, 12°13...Shallow hole.

Claims (1)

[Scope of utility model registration request] In a cassette case screwing structure in which two upper and lower outer casings forming a cassette case are fixed with tapping screws, a seat having an inner diameter into which the screw heads of the tapping screws can be fitted is placed in corresponding parts of the upper and lower two outer casings. With a borehole,
A through hole that is continuous with the counterbore hole and has an inner diameter slightly smaller than the threaded part of the tapping is provided symmetrically, and the above upper and lower 2
A shallow hole is symmetrically provided on the outer periphery of the above-mentioned through hole on the abutting surface of the two outer casings to accommodate the debris generated when screwing in the tapping screw, so that the tapping screw can be inserted in the same way from either side of the two upper and lower outer casings. A screw-fastening structure of a cassette case characterized by being configured so that it can be screwed under certain conditions.