JPH0722791Y2 - cassette - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is a mechanism for opening and closing an erroneous erasure prevention detection hole by a magnetic tape cassette for audio or video and other cassettes, in particular, an erasure prevention piece. It relates to a cassette with.

[Prior art]

The conventional cassette case is provided with an erroneous erasure prevention detection hole and an erroneous erasure prevention piece as a shutter for opening and closing the erroneous erasure prevention hole in order to prevent accidental erasure of the recorded matter on the magnetic tape. As the lock mechanism for maintaining the lock mechanism, one having a convex portion on the side of the erroneous erasure prevention and a concave portion for engaging the convex portion on the cassette case side is used.

[Problems to be solved by the invention]

However, in this conventional unlocking mechanism for the erroneous erasure prevention piece, as shown in FIG. 7, the two concave portions 5 and 6 into which the convex portion 4 provided at one place on the erroneous erasure prevention piece 3 is fitted are the upper case 1 The protrusions 4 are engaged and locked by the movement of the erroneous erasure prevention piece 3 at another position (two positions when opened / closed) provided on the inner wall plane wall.

However, when the convex portion 4 of the erroneous erasure prevention piece 3 is engaged with the concave portion 5 for closing, the operation portion 3 ₂ of the erroneous erasure prevention piece 3 is used to release the engagement between the convex portion 4 and the concave portion 5. Erase erasure prevention piece 3
When an operation is performed to move the convex portion 4, a force in the compression direction is applied to the convex portion 4 and the convex portion 4 tends to bend inward. Therefore, the moving force is increased, and the convex portion 4 engaged with the concave portion 5 is increased. It is inconvenient because the force to move around the part as a fulcrum must be increased and it is inconvenient to operate, and if operated with a strong force, it may be distorted due to excessive momentum and movement may be blocked, and it is difficult to handle. The force required in the opening and closing directions of the erroneous erasure prevention detection hole to operate the erroneous erasure prevention piece is unbalanced, and it feels uncomfortable in handling. Especially, the operation for preventing erroneous erasure is more difficult than the release operation. There was a problem in the operability that it was a thing.

In addition, it is also proposed that two protrusions are vertically provided via an arm (Japanese Utility Model Publication Nos. 55-22628 and 54-388).
(No. 99 bulletin, etc.) has a large thrust force and poor operability,
Since it only moves vertically, the erroneous erasure prevention piece is easily twisted, which is a problem of rattling.

The present invention is intended to easily eliminate these drawbacks of the related art, and both operations of the erroneous erasure prevention piece that opens and closes the erroneous erasure prevention detection hole can be performed with a uniform force, and the movement operation is smooth and easy. It greatly improves the operability in handling, and there is no rattling in the front and rear when locking, so there is no malfunction.
At the same time, it is an object of the present invention to provide a cassette in which an erroneous erasure prevention piece is temporarily fixed at the time of assembling the cassette to facilitate automatic assembly in an easily manufactured and inexpensive form.

[Means for solving problems]

This invention is, 1 _1, 1 ₂ and the cassette case erase prevention detection hole 2 mis 1 consisting, in a cassette provided with an erase prevention pieces 3 erroneous opening and closing the mis-erase prevention detection hole 2, the upper case inside Recesses 5 and 6 are provided on the plane wall and recesses 5 ₁ and 6 ₁ are provided on the rear side wall of the lower case so as to be spaced from each other, and an elastic arm 3 ₄ is extended above the erroneous erasure prevention piece 3 and is provided at the tip thereof. The recess
The convex portions 4 corresponding to 5, 6 and the elastic arm 3 ₄ are extended at the lower portion, and the convex portions 4 ₁ corresponding to the concave portions 5 ₁ and 6 ₁ are provided at the tips thereof, and the erroneous erasure is performed. bottom of the preventing pieces 3 to form a guide plate 3 ₁ slideably out those that have been decorated to a slide chamber in 11 that partitions the guide plate 3 ₁ to the lower casing 1 _2.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 1 to 6. A pair of reel hubs around which the embodiment is wound are rotatably mounted, the magnetic tape is drawn out from the front surface of the cassette case 1, and the rear of the cassette case 1 An erroneous erasure prevention detection hole 2 and an erroneous erasure prevention piece 3 which opens and closes the erroneous erasure prevention detection hole 2 are provided at the corners, and the erroneous erasure prevention piece 3 has a plurality of convex portions 4, 4 ₁ And the cassette case 1 is
A plurality of V-shaped groove recesses 5, 6, 5 ₁ , 6 ₁ are provided corresponding to the protrusions 4, 4 ₁ , respectively, and the recesses 5, 6, 5 ₁ , 6 ₁ prevent the erroneous erasure. piece 3, the recesses 5,5 ₁ that engages when closing the erase prevention detection hole 2 the erroneous engagement when said erasure preventing piece 3 mis are opened erase prevention detection hole 2 mis the recesses 6,6 ₁ wherein the cassette case 1, for example, in the union structure of upper and lower cases are provided apart from each into an upper casing 1 ₁ and the lower case 1 _second inner plane and side walls inner surface side.

The two convex portions 4 and 4 ₁ are respectively provided on elastic arms 3 ₄ and 3 ₄ that extend above and below the erroneous erasure prevention piece 3 in a separated state, and the convex portions 4 project upward. corresponding to the concave portion 5, 6 inside the upper casing 1 _1, also other protrusions 4 ₁ corresponding to the recess 5 _1, 6 ₁ of projecting from the rear inner surface of the lower case 1 ₂ laterally engaging Te I can do it. In this case, by providing one of the protrusions 4 ₁ of the convex portion of the erasure prevention member 3 erroneously on the side walls of the lower case back, that the erasure prevention member 3 erroneously to the lower casing 1 ₂ when the cassette assembly is temporarily fixed It is possible and automatic assembly becomes easy. In addition, by fitting one of the other convex portions to the inner surface of the upper case, it is possible to prevent play between the erroneous erasure prevention piece 3 and the inside of the case 1, which is effective. Further, the concave portions 5, 6, 5 ₁ and 6 ₁ respectively define the inclination angles θ ₁ and θ ₂ of the sliding slopes on the side where the convex portions 4 and 4 ₁ contact when the erasure prevention piece 3 slides. Differently, that is, the relationship between the inclination angle θ ₁ on the opening direction side and the inclination angle θ ₂ on the closing direction side is θ ₁ <θ ₂ .

The concave portion is formed by a substantially V-shaped groove, and the slopes facing each other have different inclination angles, but the slopes on both end sides may serve as stoppers on the vertical planes. Further, when the two concave portions 5 and 6 or the concave portions 5 ₁ and 6 ₁ for supporting at the time of opening and closing each have two slopes, a concave groove of the same shape is formed in the sliding direction of the convex portions 4 and 4 _1. It is also easy to manufacture in such a manner that the inclined surfaces having the same angle are arranged in the same direction, that is, the forward side and the backward side of the convex portion.

Erase prevention member 3 the false are formed respectively through the elastic arm 3 ₄ a plurality of protrusions 4, 4 ₁ integrally, slidably guide plate in the slide chamber 11, which is囲成in Ekabe the cassette case 1 3 ₁ through to interior, are provided with fitted deploying the operating unit 3 ₂ serving as a finger hooking the case side to the opening 12.

Incidentally, 4,4 ₁ provided on the erasure prevention member 3 the erroneous are the slippery shape as a curved surface or a spherical or cylindrical surface on the contact surface side.

In the figure, 7 is a front lid, 8 is a slider, 9 is a cylindrical projection for screwing, 10 is a finger hook, and 13 is a reel shaft insertion hole.

In this cassette case 1, an erroneous erasure prevention detection hole 2 is opened and closed, and an erroneous erasure prevention piece 3 is slid along the case 1 to be handled. , 4 ₁ are concave parts on the cassette case 1 side 5,5 ₁ , 6,6 ₁
When engaging and disengaging from, there are two or more engaging parts, which can be smoothly slid and moved without causing rotational movement, and can be operated without increasing the operating force. The operating force can be moved in either direction. With the same force, its operability is remarkably good, and it can be reliably used without feeling uncomfortable.

[Effect of device]

In the present invention, recesses 5 and 6 are provided on the inner plane wall of the upper case and recesses 5 ₁ and 6 ₁ are provided on the rear side wall of the lower case, respectively, and the elastic arm 3 ₄ is extended above the erroneous erasure prevention piece 3. A convex portion 4 corresponding to the concave portions 5 and 6 at the tip end thereof, and an elastic arm 3 ₄ extending at the lower portion thereof, and a convex portion 4 corresponding to the concave portions 5 ₁ and 6 ₁ at the tip end portion thereof. ₁ provided with respectively, to form a guide plate 3 ₁ at the bottom of the erasure prevention member 3 the false, by slidably it has furnished the slide chamber in 11 that partitions the guide plate 3 ₁ on the lower case 1 _2, There is an engaging mechanism that corresponds to the protruding parts that protrude upward in the vertically separated positions, the protruding parts that protrude to the side in the horizontal direction, and the recesses that fit these, preventing accidental erasure. The piece can be operated stably without rotating during the moving operation, and it will not be distorted or bogged down. , The force required in the opening direction or the closing direction is balanced, and the erroneous erasure prevention piece moves smoothly without feeling uncomfortable in handling, and one of the protrusions of the erroneous erasure prevention piece is provided in the side wall portion of the rear surface of the lower case. Since it protrudes correspondingly to and is fitted in the horizontal direction, the erasure prevention piece can be temporarily fixed to the lower case when the cassette is assembled,
Automatic assembly becomes easy, and by fitting the other convex part to the inner surface of the upper case and engaging it in a different direction from the convex part, the vertical direction and the front-back direction when sliding the erroneous erasure prevention piece Since there is no backlash, there is no inclination and movement is smooth and can be operated lightly with a small force, and the sliding direction in the horizontal direction is also regulated and guided, which greatly improves operability and proper engagement retention It is possible to prevent backlash between the erroneous erasure prevention piece and the inside of the case, that is, since there is no back and forth backlash in the locked state, no malfunction occurs and the opening / closing movement of the erasure prevention piece is almost uniform. It can be done by force, the operability is greatly improved, the handling is easy and the operation force can be reduced, the holding force of the engagement can be sufficient, and the configuration is simple and easy and inexpensive. Can be manufactured.

[Brief description of drawings]

FIG. 1 is an overall perspective view of the embodiment of the present invention viewed from the bottom side, and FIG. 2 is a plan view of a part of an erroneous erasure prevention mechanism.
FIG. 3 is a partially cut-away rear view with a part cut away, FIG. 4 is a bottom view of FIG. 3 line II, and FIG. 5 is FIG.
II An enlarged cut-away plan view of the line II, FIG. 6 is a perspective view of the erroneous erasure prevention piece, and FIG. 7 is a rear view of the conventional example under one operation state. 1 ... Cassette case, 2 ... Erase prevention detection hole, 3
…… Erase erasure prevention member 3 ₁ …… Guide plate, 3 ₄ …… Elastic arm, 4,4 ₁ …… Convex part, 5,6,5 ₁ , 6 ₁ …… Recessed part, θ ₁ , θ
₂ …… Inclination angle. 11 …… Slide room

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-13487 (JP, A) Jikkoku 55-22628 (JP, Y2) Jikkō 54-38899 (JP, Y2)

Claims (1)

[Scope of utility model registration request] [Claim 1] upper and lower cases (1 ₁₎ (1 ₂₎ and the cassette case (1) to prevent inadvertent erasure detection hole (2) formed of, erase prevention erroneous opening and closing the mis-erase prevention detection hole (2) In a cassette provided with a piece (3), recesses (5) and (6) are formed in the inner wall of the upper case, and recesses (5 ₁ ) are formed in the rear side wall of the lower case.
(6 ₁ ) are provided separately from each other, an elastic arm (3 ₄ ) is extended above the erroneous erasure prevention piece (3), and a convex portion corresponding to the concave portions (5) and (6) is provided at the tip thereof. (4), the elastic arm (3 ₄ ) is extended to the lower part, and the convex portion (4 ₁ ) corresponding to the concave portion (5 ₁ ) (6 ₁ ) is provided at the tip of the elastic arm (3 ₄ ). erasure prevention member (3) lower in forming the guide plates (3 _1), this guide plate (3 ₁₎ of the slide chamber which is partitioned in the lower case (1 ₂₎ (11)
A cassette characterized by a slidable interior inside.