JPH0722774Y2 - Magnetic tape cassette - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a magnetic tape cassette, and more particularly to a DA tape cassette.
The present invention relates to a magnetic tape cassette suitable for use in a digital audio tape recorder known as T (Digital Audio Tapercorder).

[Conventional technology]

In recent years, miniaturization and weight reduction of cassette tape recorders have progressed, and miniaturized magnetic tape cassettes used therein have become popular. Also in audio equipment, the DAT (Electronics June 1987 issue, Ltd.)
Ohmsha, published, P65-70) has been developed, and it has become possible to perform high-quality and high-density recording / reproduction over a long period of time.

And as a magnetic tape cassette compatible with the DAT,
Similar to the well-known video tape cassette, a recorder for recording and reproducing in a relatively wide frequency band has been developed. Regarding the external appearance and shape of the magnetic tape cassette for DAT, it is smaller and easier to carry than the conventional compact cassette for audio.

Therefore, the magnetic tape cassette for DAT has a frequency equal to or more than that of the conventional compact cassette for audio, and is frequently used outdoors.

On the other hand, the DAT, which is well known, converts an analog signal into a digital signal and records the signal. Therefore, if a minute scratch or dust adheres to the magnetic tape, the signal is lost (dropout). In addition, as described above, since it has the characteristic of being frequently carried and used, it is the actual situation that the magnetic tape cassette is provided with a special dustproof mechanism.

The above-mentioned special dustproof structure is, for example, provided with a slider and a locking mechanism of the slider at the bottom of the magnetic tape cassette. When the magnetic tape cassette is used, the slider moves forward while contacting the bottom surface of the cassette half to open the lower side of the opening in front of the cassette to expose the magnetic tape and allow the magnetic tape to be pulled out to make contact with the magnetic head. To Further, when the magnetic tape cassette is not used, it returns while contacting the bottom surface of the cassette half to return the previously exposed magnetic tape to the sealed state and close the lower side of the opening.

The cassette case consisting of the pair of cassette halves,
ABS resin and PS resin are generally used, and POM is used for the slider.
Resin is often used. POM for the ABS resin and PS resin
Since the resin has hardness, the bottom surface of the cassette half is scraped off by friction between the two when the slider repeats the reciprocating motion as described above for a long period of time.

[Problems to be Solved by the Invention] Shavings generated by scraping the cassette half adhere to the magnetic tape running in the vicinity of the slider to cause signal loss.

Therefore, in the prior art, a structure such as a protrusion or a stepped portion was provided on the contact surface between the cassette half and the slider, and an attempt was made to improve the contact area by reducing the amount of shavings. It is not enough by itself, and in particular, a device capable of maintaining high level recording / reproduction in high density recording for a long time has been desired.

[Purpose of device]

An object of the present invention is to solve the above problems, and to provide a magnetic tape cassette having an excellent dustproof effect by reducing the abrasion of the cassette half due to the sliding of the slider.

[Means for Solving the Problems]

The object of the present invention is to rotatably support a magnetic tape wound around a pair of hubs inside a cassette hollow formed by a combination of upper and lower cassette halves, and to forward the cassette which is a part of the running position of the magnetic tape. In a magnetic tape cassette for recording / reproducing by pulling a part of the magnetic tape out of the cassette through an opening provided on the side of the cassette, the magnetic tape cassette slides along the bottom surface of the lower cassette half in the front and rear of the cassette, A slider for opening and closing the side is provided, and a plurality of ribs for reducing the friction coefficient in the same direction as the moving direction of the slider is provided on the outer surface of the lower cassette half on the sliding surface with the slider, and further It is achieved by a magnetic tape cassette characterized in that a UV-cured coating is formed on the surface to reduce abrasion due to sliding.

That is, by forming a rib on the sliding surface of the lower cassette half with respect to the slider, the sliding area is reduced and the reciprocating motion of the slider is smoothed. The surface is not scraped and the dustproof effect is improved.

[Embodiment]

Hereinafter, one embodiment of the present invention illustrated in the drawings will be described in detail.

FIG. 1 is an external view of a magnetic tape cassette 1 to which the present invention is applied as seen from the bottom surface.

When the magnetic tape cassette 1 is not used, the front panel of the upper cassette half 2, that is, the guard panel 3 provided on the mounting side for the DAT (not shown) is closed, and the bottom surface of the lower cassette half 4 is reciprocated (arrow A). The slider 5 moving in the B direction) is also locked by a locking mechanism (not shown) in a state where it has moved to the front surface portion.

In this state, the pair of reel shaft insertion holes 6a, 6b formed in the lower cassette half 4 and the slider shaft insertion holes 7a, 7b formed in the slider 5 do not communicate with each other. Therefore, the cassette halves 2 and 4, the guard panel 3, and the slider 5 provide dustproof measures to the magnetic tape (none of which is shown) wound around the pair of hubs. become.

On the other hand, when the magnetic tape cassette 1 is attached to the DAT, that is, when the slider is used, the slider 5 is moved in the direction of the arrow B, and the reel shaft insertion holes 6a, 6b, 7a, 7b communicate with each other at the stop position. A reel shaft (not shown) is inserted to drive the pair of hubs to rotate.

Further, the guard panel 3 is rotated upward, that is, in the direction of the arrow C, around the support shaft 8 through which the upper cassette half 2 is inserted. As a result, the opening portion of the magnetic tape cassette 1, that is, the mouth portion 9 shown in FIG. 2 is opened, and the magnetic tape is exposed on the front surface and pulled out by the recording / reproducing apparatus so that it can be brought into contact with the magnetic head.

Next, the sliding mechanism of the slider 5 will be described with reference to FIGS. 2 and 3.

The lower cassette half 4 is formed in a box-shaped structure including a lower surface portion 11, wall portions 12, 13, 14 surrounding the lower surface portion 11 from three sides, and a wall portion 16 having a plane concave shape. Then, the wall portions 12, 14
Are formed on the slopes in the directions facing each other, and these slopes 12a and 14a serve as guides for the slider 5.

On the other hand, the slider 5 includes a flat plate portion 21 and guide portions 22 and 23.
The guide portions 22 and 23 are provided with slanted surface portions 22a and 23a that slide on the slanted surface portions 12a and 14a.

Further, on the bottom surface of the lower cassette half 4, two ribs 24, 25 having a semicircular cross section as shown in FIGS. 1 and 3 are provided.
Are formed.

The ribs 24 and 25 have the same arrows as the slider 5 as described above.
When sliding in the A and B directions, it is provided in order to reduce the contact area with the bottom surface of the lower cassette half 4 to make the sliding smooth and reduce the generation of the above-mentioned shavings.

However, since the structure in which the ribs 24 and 25 are provided in this way is insufficient, in the present embodiment, the two ribs 24 and 25 are provided.
UV cured coatings 24a and 25a were formed on the surface of. The UV curable coatings 24a and 25a are formed by coating the surface of the ribs 24 and 25 with a UV curing agent such as an unsaturated polyester type, urethane-acrylate type, epoxy-acrylate type, polyester-acrylate type, etc. Surface hardening can be achieved by the method described below.

As a result, even when the lower cassette half 4 as well as the upper cassette half 2 is made of ABS resin or PS resin, the surface hardness of the ribs 24, 25 is increased and the wear resistance is improved. Therefore, the slider 5 formed of POM resin
However, even if the ribs 24, 25 are repeatedly slid over a long period of time, they are hardly scraped off because of improved wear resistance. In other words, almost no shavings are generated from the ribs 24, 25, and almost no shavings adhere to the magnetic tape, so there is no signal loss of the magnetic tape and it can be said that it is almost perfect dust-proof measure. Will be taken.

Incidentally, the dust-proof measures by the UV curing coating 24a, 25a, by taking measures in the vicinity of the magnetic tape running other than the above,
Exhibits a further dustproof effect.

For example, the guard panel 3 is rotatable by inserting the support shaft 8 into the insertion hole 30 formed in the upper cassette half 2 as shown in FIG.
Since they rub against each other, shavings are likely to occur. Moreover, the insertion hole 30 is in the vicinity of the mouth portion 9 and is in a close distance to the running magnetic tape.

Therefore, when shavings are generated from the insertion hole 30, there is a great possibility that the shavings adhere to the magnetic tape.
Form a film. As described above, by forming the UV coating on the member in which shavings are easily generated in the vicinity of the magnetic tape, the dustproof effect can be dramatically improved, and the reliability of the magnetic tape cassette can be enhanced.

Further, although the above-mentioned embodiment relates to a magnetic tape cassette for audio, the present invention can be applied to a magnetic tape cassette for video.

[Effect of device]

Since the present invention is configured as described above, it has the effects described below.

Since a plurality of ribs that reduce the coefficient of friction are provided at the position where the slider slides on the bottom surface of the lower cassette half that constitutes the magnetic tape, and a UV cured coating that is cured by ultraviolet irradiation is formed on the surface of the plurality of ribs, the slider slide There is no scraping of the lower cassette half due to movement, removal of shavings from the magnetic tape, the dustproof effect of the magnetic tape cassette is improved, and the slidability of the slider can be kept good for a long time. .

Further, according to the present invention, the cassette half can be formed by using ABS resin or PS resin, which is inexpensive and easy to mold, as a case constituent material, so that a high-performance magnetic tape cassette that is inexpensive and has an excellent dustproof effect can be obtained. .

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is an external view of the magnetic tape cassette as seen from the bottom, FIG. 2 is a perspective view showing the shapes of the lower cassette half and the slider, and FIG.
FIG. 4 is a sectional view of a main part of the magnetic tape cassette, and FIG. 4 is a partially cutaway perspective view of the magnetic tape cassette. Symbols in the figure: 1 ... magnetic tape cassette, 2 ... upper cassette half,
3 …… Guard panel, 4 …… Lower cassette half, 5 ……
Slider, 6a, 6b, 7a, 7b …… Reel shaft insertion hole, 1
2a, 13a, 22a, 23a …… guide part, 24, 25 …… rib, 24a, 25a
…… UV curing film.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-202380 (JP, A) real-open Sho-62-80277 (JP, U) real-open Sho-56-51183 (JP, U) real-open Sho-55- 132785 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A magnetic tape wound around a pair of hubs is movably supported inside a cassette hollow formed by a combination of upper and lower cassette halves, and is provided on the front side of the cassette which is a part of the running position of the magnetic tape. In the magnetic tape cassette for recording and reproducing by pulling a part of the magnetic tape out of the cassette through the opened opening, slide the front and rear of the cassette along the bottom surface of the lower cassette half to open and close the lower side of the opening. A slider for tightening is provided, and a plurality of ribs for reducing the coefficient of friction are provided on the outer surface of the lower cassette half on the sliding surface with the slider in the same direction as the moving direction of the slider. A magnetic tape cassette characterized by having a UV-cured coating that reduces wear due to movement.