JPS6132284A - Magnetic tape cassette - Google Patents

Abstract

PURPOSE:To improve the rigidity of a front lid by forming a U-shaped groove having an inflection point as a back lid guide groove and allowing a back lid to operate only inside the front lid. CONSTITUTION:The guide groove 4 is formed in a U shape having a curve point at its upper end and has a slanting groove part 41 for rotating the back lid 7 clockwise around a support shaft 8, and the lower end 71 of the back lid 7 is moved to behind a tape T. Further, a vertical groove part 42 is formed at a halfway part connecting with the groove part 41, and the lower end 71 guides the back lid 7 to inside and over the tape T while moved to behind the tape T. The front lid 5 is rotatable around the support shaft of the front lid 5 and the back lid 7 is coupled with the front lid 5 through the support shaft 8; and an axial projection part 75 is provided at part of it and the whole of the back lid 7 is positioned by the guide groove 4 of a tape cassette 1. The lids 5 and 7 are opened and closed without contacting the tape T and the back lid 7 is positioned inside the front lid 5. Consequently, the sectional shape of the front lid 5 provides tolerance to bending and the rigidity is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a magnetic tape cassette, and is particularly useful when applied to a lid (zict) structure for the purpose of protecting the tape.

<Prior Art> The lid attached to a tape cassette is primarily intended to protect the tape when the cassette is being carried.

On the other hand, when the tape cassette is loaded into a magnetic recording/reproducing device (hereinafter referred to as a VTR), this lid can sufficiently expose the tape and provide a wide threading area, making it easy to pull out the tape. It is desirable that the overall height of the cassette be kept as low as possible during the above-mentioned interval.

By the way, in conventional tape cassettes, even when the lid of the so-called single-lid system is closed, there is a risk that a finger may be inserted into the back of the lid and the tape may be directly touched.

Therefore, a double-lid system that combines two lids, a front lid and a back lid, has also been proposed.

<Problems to be solved by the invention> In conventional devices, the back lid is easy to open from the outside, and the back lid slides to the outside of the front lid, making it difficult to provide a large cassette crimping area with the cassette compartment. Otherwise, the threading area is determined by the shape of the back lid guide groove, and the back lid must be slid to the outside of the front lid, making it impossible to support the cassette guide at both ends due to its shape, and the rigidity of the front lid decreases. There were various problems that could occur.

Therefore, the present invention has been proposed in view of the above-mentioned conventional situation, and the lid is stable when the lid is closed. The purpose of this is to make it possible to reduce the height of the building to the ground and to keep the overall height from being too high.

<Means for Solving the Problems> The present invention improves the position and shape of the back lid guide groove in a double lid type tape cassette in which the lid is composed of a front lid and a back lid, and improves the position and shape of the back lid guide groove. The feature is that the back lid operates only on the inside of the front lid by forming a shaped groove.

<Function> In the magnetic tape cassette of the present invention, by pushing up the lower end 71 of the back lid 7 with the push-up lever 9 provided on the VTRgAll, the back lid 7 is rotated along the guide U-shaped groove 4. At this time, the front lid 5, which is pivotally connected to the back lid 7, is also rotated about the support shaft 6 and moved upward to open the fretting area, and the above operation is performed. It can be closed by performing the opposite operation.

During the opening and closing operations of the lids 5 and 7, the back lid 7 is always located inside the front lid 5, and in the closed state, the front lid 5 covers the entire threading area and the back lid 7 is completely inside the threading area. It is covered.

<Embodiment> An embodiment of the present invention shown in FIGS. 1 to 4 will be described.

First, in these figures, 1 is a tape cassette, and a threading area 2 formed in a concave shape is provided at the center of the front end of the tape cassette. Note that grooves 4 for back lid guides, which will be described later, are formed on both inner surfaces of the concave peripheral wall 3 surrounding the area 2 so as to face each other. Reference numeral 5 designates a front lid, which has an L-shaped cross section with a horizontal portion 51 and a vertical portion 52 connected to each other, and has a lid side plate portion which is formed in an elongated shape to cover the threading area 2 and extends from both ends thereof. is rotatably supported by a support shaft 6 provided on the tape cassette.

As is clear from FIG. 1, the guide groove 4 has an overall shape with a curved point at the upper end. That is, the lower end portion has an inclined groove portion 41 that allows the back lid 7 to rotate clockwise around the support shaft 8, and the back lid 7 is rotated by the action of the core portion 41.
The lower end 71 side is behind the tape T.

be moved towards Further, a midway portion following the groove portion 41 is a vertical groove portion 42, and the back lid 7 is opened with the lower end 71 side moved to the rear of the tape T.
is guided upward inside the tape T. Further, at the upper end of the vertical groove 42, there is an inclined groove 43 for gradually rotating the back lid 7 counterclockwise, and a slight vertical groove 44.
are connected.

Also, on the lower side near both ends of the horizontal portion 51 of the front lid 5, there are provided arms 53 for supporting the back lid that extend downwardly and protrude along the inside of the vertical portion 52. 7
is a back lid, which is formed to have a slightly narrower width than the width of the threading area 2, and is rotatably supported by the arm 53 through a support shaft 8 at both ends of the midway portion.

In addition, the lower end 71 of the back lid 7 comes into contact with the upper end abutment engagement surface 91 of the push-up lever 9, which will be described later. An arm 74 is provided extending from the lower back side of both ends, and a shaft-like projection that fits into the groove 4 is provided on the outer side of the tip.

Therefore, in FIG. 1, the front lid 5 is rotatable around the support shaft of the tape cassette 1.

On the other hand, the back lid 7 is connected to the front lid 5 and the support shaft 8.
The tape cassette 1 has a shaft-like protrusion 75 on its part, and the guide groove 4 provided on the side surface of the threading area of the tape cassette 1 determines the position of the entire back lid. .

Note that 50.70 in the figure indicates a state in which the lids 5 and 7 are open, and the IJ hood rotates approximately 751 in the illustrated example. Further, T is a tape, and when the lids 5 and 7 are closed, the lids 5 and 7 are covered with a tape that can be seen from the periphery.

FIG. 2 schematically shows the state of the front lid 5 at every 15 degrees of rotation angle in the process of opening and closing the lids 5 and 7. As is clear from the figure, the valley lids 5 and 7 open and close while avoiding contact with the tape T.

Further, at this time, the back lid 7 is located only inside the front lid 5.

It is schematically shown in a state in which the pace is fixed at every 15 degrees of rotation angle, and the upper end abutment engagement surface 91, which is the top surface for pushing up the lid pushing up lever 9 protruding from the VTR, and the lower end 71 of the back lid 7 are shown schematically. It shows the positional relationship. That is, the lower end 71 is always in a state of facing and abutting against the upper end abutting and engaging surface 91 of the push-up lever 9.

<Effects> In the present invention, first, the cross-sectional shape of the Freon I-IJ hood became resistant to bending, and its rigidity was improved. Also, the back lid does not need to slide over the front lid, so
There is no need to provide a tapered shape or the like in the connecting bending part between the horizontal part 51 and the vertical part 52 of the Freon I-IJ hood, and the space factor is improved. It became possible to install an upper half of the Since the guide groove is a U-shaped groove, the distance from the front surface of the cassette 1 to the guide groove 4 can be made small, and therefore the threading area area can be determined by considering only the size of the guides to be stored in the area. can. In addition, the back lid 7 feels fully covered by the front lid 5 in the closed state and does not extend outside the cassette, so there is no risk of it being accidentally opened from the outside. Further, even when the back lid 7 is opened, it does not slide to the outside of the front lid 5, so that a relatively large cassette compression area can be provided by the cassette compartment when loading the VTR. Moreover, as a result of forming the lid guide groove 4 in a U-shape, the amount of movement of the lower end 71, which is the lowest point of the back lid 7, in the front-rear direction during opening of the lid can be made relatively small. It is possible to incorporate a lid opening/closing mechanism by pushing up the back lid 7 like a lever 9.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of the main part showing an embodiment of the present invention, FIG. 2 is a side sectional view of the main part showing the moving state of the lid during opening/closing operation, and FIG. 3 is a sectional side view of the main part showing the lid during opening/closing operation FIG. 4 is a side sectional view of a main part schematically illustrating a state where the tape cassette is moved and fixed to the same base, and FIG. 4 is a partially cutaway plan view of the tape cassette. 1...Tape cassette 2...Threading area 4...
...Guide groove 5 ...Front lid 6 ...... Support shaft

Claims (1)

[Claims] In a cassette in which the lid mechanism that opens and closes the threading area formed on the front side of the tape cassette body is a double-lid system consisting of a front lid and a back lid, the back lid has a lower end engaging portion connected to the threading area of the tape cassette. The front lid is movably supported along U-shaped guide grooves formed on both side walls, and the front lid is pivotally connected to the middle part of the back lid at both inner ends, and the lower end of the back lid is connected to the middle part of the back lid. A magnetic tape cassette characterized in that the part is in contact with a push-up lever provided on the side of a magnetic recording/reproducing device.