JP2000182355A - Magnetic tape cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the short-circuit of a substrate of an ID board by preventing the partial damage, etc., of the plating on contact points due to minute barrs on the substrate of the ID board. SOLUTION: The signal transfer as to the kind or the use, etc., of magnetic tape is carried out in between a recording/reproducing device (hard device) through the contact points 21a-21d. Among each of the contact points 21a-21d of the ID board, the 1st contact point 21a performs the function for discriminating the thickness of the magnetic tape, the 2nd contact point 21b performs the function for discriminating the type of the magnetic tape, the 3rd contact point 21c performs the function for discriminating the use of the magnetic tape, and the 4th contact point 21d performs the function for grounding (GND). That is, the thickness of the magnetic tape is discriminated by reading out the resistance value between the 1st contact point 21a and the 4th contact point 21d, at the side of the recording/reproducing device. The specified space A is secured between the end part of the gold plated part on the copper foil of the ID board 20 and the end surface of the printed circuit board 22 of the ID board 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape cassette provided with an ID board for identifying the type or use of a magnetic tape on a hard device side, and more particularly to a structure for preventing a short circuit of an ID board substrate. .

[0002]

2. Description of the Related Art In general, in audio equipment, video equipment and the like, a magnetic tape cassette for recording / reproducing a magnetic tape wound around a pair of tape reels so as to be able to run in a cassette half is often used. . Referring to FIG. 4, a pair of tape reels (not shown) around which a magnetic tape (not shown) is wound, as a magnetic tape cassette 30 conventionally used for, for example, a DVC (digital video cassette), is connected to an upper cassette half 31. Some of the lower cassette halves 32 forming a pair are rotatably supported.

An ID board 33 for identifying the type or use of the magnetic tape, and an erroneous erasure preventing piece 34 for preventing erroneous erasure of the recorded contents of the magnetic tape are provided at a front corner of the lower cassette half 32 in FIG. Each is provided. Referring to FIGS. 4 to 6, the ID board 33 is provided in the lower cassette half 32 at a position surrounded by the side wall 35 and the partition ribs (not shown). The ID board 33 connects a plurality of (four in FIG. 4) contacts 36 to the lower cassette half 32.
A signal such as the type or use of a magnetic tape is exchanged with a recording / reproducing device (hard device) (not shown) through the contact 36.

[0004] The ID board 33 is manufactured in the following procedure. First, a copper foil is attached on a printed circuit board 38 made of a substrate material such as glass epoxy resin,
A required pattern is printed (etched) to remove an unnecessary portion of the copper foil, and a copper foil of a required shape (rectangular shape in FIG. 5) serving as a contact 36 is formed on the printed circuit board 38. Next, after cleaning the printed circuit board 38, a gold plating process is performed on the copper foil. The gold plating of the copper foil is an indispensable process to prevent detection failure due to repeated sliding with the hardware device. Further, a required shape for accommodating the printed circuit board 38 in the lower cassette half 32 by punching with a press die (in FIG. 5, a flat plate shape and a substantially L shape in plan view).
Process into

[0005]

In the above-described conventional magnetic tape cassette 30, when the printed board 38 of the ID board 33 is punched by a press die, the end face of the contact 36 of the printed board 38 is moved in the direction of arrow B in FIG. Small burr 3 along
9 was caused, and there was a problem that the burrs 39 caused partial breakage 40 of the gold plating on the copper foil. If gold-plated burrs are generated or partially damaged, or the like 40 occurs, as the magnetic tape cassette 30 is repeatedly attached to and detached from the recording / reproducing apparatus, the burrs further spread and reach the insulating portion, or fragments are attached to the insulating portion. Therefore, there is a concern that the printed circuit board 38 may be short-circuited.

SUMMARY OF THE INVENTION It is an object of the present invention to reliably prevent partial breakage of plating on a contact due to minute burrs of an ID board substrate, thereby reliably preventing a short circuit of the ID board substrate. It is to provide a magnetic tape cassette which can be used.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hard device by contacting a contact on a substrate exposed from an opening formed in a lower cassette half with a corresponding contact on the hard device. ID to identify the magnetic tape on the side
In a magnetic tape cassette provided with a board, the ID
The contact point of the board is plated, and a predetermined distance is secured between the end of the plated part and the end face of the board. And a magnetic tape cassette.

[0008]

According to the magnetic tape cassette of the present invention,
The D board makes the hardware device identify the type or use of the magnetic tape by contacting the contacts on the substrate exposed from the opening formed in the lower cassette half with the corresponding contacts on the hardware device. . A plating process is performed on the contacts of the ID board. Since a predetermined interval is secured between the end of the plated portion and the end surface of the substrate, the punching blade does not come into contact with the plated portion at the time of punching by the press. Therefore, no burr or damage occurs in the plated portion, and short-circuit of the contact due to the metal piece can be prevented.

As described above, from the viewpoint of preventing the occurrence of burrs that cause a short circuit, the larger the distance, the better. However, as shown in FIG. 7, the magnetic tape cassette 30 slides the plated portion 36 of the ID board 33 with respect to the corresponding contact 52 on the hardware device 50 side in the direction of arrow C (in FIGS. 2 and 7). If the gap is made too large, the exposed portion (the portion without plating) of the ID board 33 comes into sliding contact with the contact 52, and stable contact detection may not be performed. Therefore,
It is desirable that such an interval be 0.25 mm or less from the viewpoint of electrically stable contact detection.

On the other hand, when the size of burrs, damages and the like, which are problematic, were investigated and examined, the size was found to be approximately 0.02.
０．１0.1 mm. Therefore, in consideration of the stability of the contact detection and the variation in the processing accuracy of the product, the interval is set as follows.
The thickness is preferably 0.05 to 0.25 mm, but preferably 0.1 to 0.15 mm in consideration of stability.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing a lower cassette half of a magnetic tape cassette according to an embodiment of the present invention, FIG. 2 is a plan view showing an ID board of the magnetic tape cassette of FIG. 1, and FIG. It is a principal part expansion perspective view of the ID board of FIG.

In FIG. 1, a magnetic tape cassette 10
Is a pair of tape reels 11 (not shown) on which a magnetic tape (not shown) is wound.
It is rotatably supported by a lower cassette half 12 that forms a pair with an upper cassette half (not shown). The lower cassette half 12 is integrally formed of a synthetic resin such as an ABS resin.

The lower right corner 1 of the lower cassette half 12 in FIG.
The ID board 3 is provided with an ID board 20 for identifying the type or use of the magnetic tape. The ID board 20 is disposed in the lower cassette half 12 at a position surrounded by the side wall 14 and the partition ribs 15.

As shown in FIGS. 2 and 3, the ID board 20 has a plurality of (four in FIG. 1) contacts 21a to 21d.
Is exposed from an opening (not shown) provided at the corner 13 of the lower cassette half 12 and the contacts 21a to 21d
, A signal such as the type or use of the magnetic tape is exchanged with a recording / reproducing device (hard device) (not shown).

Of the contacts 21a to 21d of the ID board 20, the first contact 21a at the left end in FIG. 2 is for identifying the thickness of the magnetic tape, and the second contact 21b from the left in FIG. For identification, third contact 2 at the third from left in FIG.
1c has a function for identifying the use of the magnetic tape, and the fourth contact 21d at the right end in FIG. 2 has a function for grounding (GND). That is, the thickness of the magnetic tape is identified by reading the resistance value between the first contact 21a and the fourth contact 21d on the recording / reproducing device side. The type of the magnetic tape is identified by reading the resistance value between the second contact 21b and the fourth contact 21d on the recording / reproducing device side. Further, the third contact 21c and the fourth
By reading the resistance value between the contacts 21d on the recording / reproducing device side, the use of the magnetic tape is identified.

The ID board 20 is manufactured in the following procedure. First, after attaching a copper foil on a printed circuit board 22 made of a substrate material such as glass epoxy resin,
A required pattern is printed (etched) to remove unnecessary portions of the copper foil, and a copper foil of a required shape (rectangular shape in FIG. 2) to be the contacts 21a to 21d is formed on the printed circuit board 22. Next, after cleaning the printed circuit board 22, a gold plating process is performed on the copper foil. The gold plating on the copper foil prevents detection failure due to repeated sliding with the recording / reproducing apparatus.
Further, the printed board 22 is processed into a required shape (a flat plate shape and a substantially L-shape in plan view in FIG. 2) for accommodating the printed circuit board 22 in the lower cassette half 12 by punching using a press die.

A predetermined gap A is provided between the end 23 of the portion of the ID board 20 which has been subjected to the gold plating on the copper foil and the end face 24 of the printed board 22 of the ID board 20. In the present embodiment, the interval A is 0.1 mm. Since the interval A is ensured, even when a fine burr 39 (see FIG. 6) occurs on the printed board 22 during the punching process of the printed board 22 by the press die,
Partially damaged gold plating 40 due to burrs 39 (see FIG. 6)
Is reliably prevented.

As described above, according to the above embodiment, the ID
An edge 23 of a gold-plated portion on the copper foil of the board 20;
Since the predetermined interval A is secured between the ID board 20 and the end surface 24 of the printed board 22, even when a small burr 39 occurs on the printed board 22 during the punching of the printed board 22 by the press die, It is possible to reliably prevent partial damage 40 of the gold plating due to the burrs 39. Thereby, even when the attachment and detachment of the magnetic tape cassette 10 to and from the recording / reproducing apparatus are repeated, the printed circuit board 2
2 can be reliably prevented.

[0019]

As described above, according to the present invention, the contact point of the ID board is plated, and the end of the plated part and the end face of the substrate are connected to each other. A predetermined interval is secured between them. Therefore, I
It is possible to reliably prevent minute burrs on the substrate of the D board and partial damage of plating on the contacts due to burrs. Thereby, the short circuit of the substrate of the ID board can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a plan view showing a lower cassette half of a magnetic tape cassette according to an embodiment of the present invention.

FIG. 2 is a plan view showing an ID board of the magnetic tape cassette of FIG.

FIG. 3 is an enlarged perspective view of a main part of the ID board of FIG. 2;

FIG. 4 is a perspective view showing a conventional magnetic tape cassette.

FIG. 5 is a plan view showing an ID board of the magnetic tape cassette of FIG.

6 is a perspective view of the ID board of FIG. 5 and an enlarged perspective view of a main part.

FIG. 7 is a cross-sectional view of the vicinity of an ID board when a magnetic tape cassette is loaded in a hardware device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Magnetic tape cassette 11 Tape reel 12 Lower cassette half 20 ID board 21a-21d Contact point 22 Substrate (printed circuit board) 23 Edge part of plated part of ID board 24 Edge face of ID board substrate A Gold plating of ID board The distance between the edge of the processed part and the edge of the printed circuit board

Claims (1)

[Claims] 1. An ID board for identifying a magnetic tape to a hardware device by contacting a contact on a substrate exposed from an opening formed in a lower cassette half with a corresponding contact on a hardware device. In the magnetic tape cassette, a plating process is performed on the contact of the ID board, and a predetermined distance is provided between an end of the plated portion and an end surface of the substrate. A magnetic tape cassette, characterized in that a magnetic tape cassette is secured.