JPH087975B2 - Tape cassette - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cassette, and more particularly to a tape cassette suitable for a magnetic recording / reproducing apparatus such as a video tape recorder.

2. Description of the Related Art Generally, a tape cassette mounted on a magnetic tape device such as a video tape recorder has a structure in which a magnetic tape stretched over the front surface of a case body is sandwiched between a front lid and a back lid provided on the front surface of the case body. (For example, JP-A-63
-175279 gazette).

Hereinafter, a conventional tape cassette as described above will be described with reference to the drawings.

FIG. 8 is a perspective view of a conventional example, FIGS. 9 and 10 are cross-sectional views of a main part of a conventional tape cassette, and FIG. 11 is a waist plan view of a lower cassette case.

4 to 6, an opening 61 is provided on the front surface of the tape cassette 64 along substantially the entire width of the cassette. A magnetic tape 59 is stretched over the opening 61 by a guide portion 72, and is normally covered by a front lid 58 and a back lid 57.

The front lid 58 is rotatable about a fulcrum pin 65. A first coil spring 66 is attached to the fulcrum 65, and constantly biases the front lid 58 in the closing direction.

Further, a pair of bracket portions 67 is provided inside the upper surface of the front lid 58. A pair of support pins 60 provided at the left and right ends of the back cover 57 are inserted into the bracket portion 67, and the back cover 57 is rotatable about the support pins 60.

A pair of guide pins 55 provided at both ends of the back lid 57 are slidably inserted into the guide grooves 56. The pair of guide grooves 56 have the same left and right shape, and the guide portion 72 and the guide groove 56 are The tape cassettes 64 are provided at positions where they overlap each other in the width direction.

Further, the guide portion 72 is formed of a semi-circular resin molding in order to secure a wide tape pass area 59a, 59b.

A lock member 50 is rotatably provided on the cassette case 68. Further, a leaf spring 70 is attached to the rear side of the lock member 50, and the lock member 50 is urged to rotate in the forward direction.

The projection 52 provided on the side plate 54 of the front lid 58 and the claw portion 53 of the lock member 50 are always engaged with each other to prevent the front lid 58 from rotating.

Regarding the tape cassette configured as above,
The operation will be described below. The tape cassette 1 always prevents the careless opening of the front lid 58 by the locking member 50.

On the other hand, when the tape cassette 1 is inserted into a video tape recorder (hereinafter referred to as VTR), the lock member 50 is moved in the A direction against the leaf spring 70 by the lock release member 71 provided on the VTR side as shown in FIG. The front cover 58 is rotated so that the engagement between the projection 52 and the claw portion 53 is released, and the front lid 58 can be rotated.

After that, as shown in FIG. 6, when moving in the B direction,
The front lid 58 opens upward, and the back lid 57 has the support pin 60 as the fulcrum pin.
The guide pin 55
Is guided along the guide groove 56 and is opened.

The opening operation when mounting on the VTR has been described above, but the opening operation is exactly the opposite of the opening operation.

SUMMARY OF THE INVENTION However, in the above-mentioned configuration, in order to secure a wide tape path area in which the tape is fed out from the cassette, the resin shape is a semicircular shape, and the guide accuracy is poor. The influence of the change is great and the reliability against tape damage is poor, and a semicircular guide member made of a metal post is conceivable, but it is extremely difficult to manufacture and there is a problem that the cost is increased significantly.

In view of the above problems, the present invention secures a sufficient tape path area even with a metal post that has good guide accuracy and is less affected by changes in the environment and time, and improves reliability against tape damage, and The tape cassette provides good dust resistance.

Means for Solving the Problems In order to solve the above-mentioned problems, a tape cassette according to the present invention comprises a pair of tape reels around which a tape is wound and both ends of the tape are respectively locked, and the tape is stretched on the front surface. A cassette case containing the pair of tape reels, an opening provided inside the tape stretched on the front surface, a guide member for guiding the tape stretched on the front surface, and the cassette case. A front lid that is pivotally supported on the side surface and covers the front surface of the tape stretched over the front surface by rotation; a back lid that is pivotally supported by the front lid and covers the back surface of the tape by rotation; A pair of guide grooves formed on the left and right side surfaces of the cassette case facing the opening for restricting rotation, the guide groove being provided rearward of the guide portion, and the guide portion and the cassette case. It is provided at a position where it does not overlap in the width direction.

Effect The present invention has good guide accuracy due to the above-mentioned configuration,
It is possible to provide a tape cassette that secures a sufficient tape path area even when using a metal post that is less affected by changes in the environment and aging, improves reliability against tape damage, and has good dustproofness against tape.

First Embodiment A tape cassette according to an embodiment of the present invention will be described below.
It will be described with reference to FIGS.

FIG. 1 is a plan view with an upper cassette case and a front lid removed according to an embodiment of the present invention, FIG. 2 is a plan view with a back lid further removed, and FIG. 3 is a plan view of a tape cassette. FIGS. 4 and 5 are sectional views of the tape cassette in the closed and opened state of the XX portion, and FIGS. 6 and 7 are sectional views of the tape cassette in the closed and opened state of the YY portion. .

1 to 7, the tape cassette 1 has an upper cassette case 2 and a lower cassette case 3 which are fitted to each other to form a flat cassette case as shown in FIGS.
Two cassette reels 4a, 4b arranged side by side on the same plane,
And a cassette case accommodating the magnetic tape 5.

The cassette reels 4a and 4b fix the start end or the end of the magnetic tape 5, respectively, and surround the magnetic tape 5 with the magnetic tape 5.
Is wound.

6 is a front lid that covers the upper surface and the front surface of the magnetic tape 5,
As shown in FIG. 3, it has a substantially U-shape. Further, the upper and lower cassette cases 2 and 3 support a pair of front lid rotation supporting shafts 6a and 6b provided on both left and right side plates of the front lid 6, and the front lid 6 rotates around the rotation supporting shafts 6a and 6b. Move. Further, the front lid 6 is always biased in the closing direction by a front lid biasing spring 7 provided on the pivot shaft 6b. The biasing spring 7 is composed of a torsion coil spring, one end of which is supported by the upper cassette case 2 and the other end of which is supported by a pin 6c provided on the front lid rotation support shaft 6b.

An opening 8 is a space into which a post (not shown) for pulling out the magnetic tape 5 from the upper and lower cassette cases 2 and 3 enters. Further, the magnetic tape 5 is extended to the front surface of the upper and lower cassette cases 2 and 3 by being guided by the guide posts 9a and 9b made of stainless steel at the substantially left and right ends in the upper and lower cassette cases 2 and 3.

The stainless steel guide posts 9a and 9b are made of a non-magnetic material and have a high surface roughness of 0.4 μm or less.

Reference numeral 10 is a back cover that covers the back surface of the opening 8 of the magnetic tape 5. In the back cover 10, a pair of back cover rotation supporting shafts 10a and 10b protruding left and right are pivotally supported by a bearing portion 6e of a bracket portion 6d provided integrally with the front cover 6. The back cover 10 is a pivot shaft 10a, 10b.
It is rotatable around.

Reference numeral 11a is a guide groove for guiding the guide pin 10c at the left end of the back lid 10, and is provided at the left end of the opening 8 of the lower cassette case 3. The guide groove 11a is the guide post 9a and the width direction of the tape cassette 1. Guide post that does not overlap with A
It is located almost behind 9a.

Reference numeral 11b is a guide groove for guiding the right guide pin 10c at the right end of the back cover 10, and is provided at the right end of the opening 8 of the lower cassette case 3. As is clear from the figure, the left and right guide grooves 11a and 11b are different in distance from the front surface 16 of the tape cassette, and 11a and 11b are formed in different groove shapes.

Dotted lines 5a and 5b in FIGS. 1 and 2 indicate tape path areas where the magnetic tape 5 can be pulled out from the left and right tape rolls 13a and 13b during normal running.

The tape path areas 5a and 5b are formed in a range that does not contact the guide posts 9a and 9b in the tape cassette 1.

The alternate long and short dash lines 5c and 5d are the tape rolls 13 on the left and right when running at high speed.
The tape paths pulled out from a and 13b are shown, and are in contact with the guide posts 9a and 9b.

Reference numeral 12 denotes a notch portion of the lower cassette case 3 which is notched because the guide post 9a is brought close to the opening 8 in order to secure a large left and tape pass area 5a during normal traveling.

Reference numeral 10e is a rib that is provided at the left end of the back lid 10 and supports the left guide pin 10d. When the lid is closed, the notch 12 is covered with the bracket portion 6d of the front lid 6.

Reference numerals 13a and 13b are tape rolls in which the magnetic tape 5 is wound around the cassette reels 4a and 4b.

Reference numeral 14 denotes a lighthouse including a photodiode provided on a VTR (not shown) that emits light toward a light receiving element (not shown) for detecting the start and end of the magnetic tape 5.

Reference numeral 15 is an insertion hole provided in the bottom surface of the lower cassette case 3 for allowing the lighthouse 14 to enter the tape cassette 1.

The light from the lighthouse 14 inserted into the insertion hole 15 passes through the light receiving paths 16a and 16b when the lid is opened, and the upper and lower cassette cases 2 and 3
Is guided from the inside to the outside through light receiving holes 17a and 17b provided on the left and right side surfaces of the upper and lower cassette cases 2 and 3, respectively.

18a and 18b are cassette case positioning holes provided in the lower cassette case 3.

Reference numeral 19 denotes a lock portion (not shown) provided on a side plate of the front lid 6 so that the front lid 6 is opened carelessly when the VTR (not shown) is not attached and the magnetic tape 5 is not damaged. It is a lock member that engages and locks the front lid 6, and the lock member biasing spring 20 always biases the lock member 19 in a direction to engage with the front lid lock portion.

Numerals 21a and 21b are reel brakes for preventing tape slack due to careless rotation of the cassette reels 4a and 4b wound with the magnetic tape 5 when the VTR is not attached, and axes provided on the upper and lower cassette cases 2 and 3. Rotate around 22a, 22b,
The tip is a cassette reel due to a constant biasing spring (not shown)
It is biased in a direction to engage with 4a, 4b.

Reference numeral 23 is a notch groove provided in the upper and lower cassette cases 2 and 3, and is a groove for opening a lid for opening a lid opening member (not shown) provided on the VTR side to push up the front lid 6 in the opening direction. is there.

The operation of the tape cassette configured as described above will be described below.

FIG. 4 is a view of a closed lid, and the magnetic tape 5 stretched over the opening 8 is normally covered with the front lid 6 and the back lid 10, respectively.

Even if the front lid 6 is intentionally opened upward, the lock member 19 and the front lid lock portion (not shown) of the front lid 6 come into contact with each other,
It does not rotate in the direction of arrow I.

In this way, damage to the tape due to careless opening of the front lid is prevented.

Next, when the tape cassette 1 is inserted into a VTR (not shown), the lock member 19 is rotated clockwise about the shaft 24 to become 19a shown by a broken line, and the front lid lock portion is disengaged from the front lid. The upper lid of 6 can be opened.

Next, by moving the tape cassette 1 in the direction of arrow II, the lid opening member (not shown) provided on the VTR side is inserted into the lid opening groove 23 of the upper and lower cassette cases 2 and 3 provided inside the front lid 6. When the tape cassette 1 enters and moves in the II direction of the tape cassette 1, a force is generated to rotate the front lid 6 clockwise about the front lid rotation support shafts 6a and 6b. When the front lid 6 is further moved in the direction of arrow II, the front lid 6 is opened upward against the front lid biasing spring 7 around the support shafts 6a and 6b.

Further, the back cover 10 rotates integrally with the front cover 6 while being restricted by the left guide groove 11a and the right guide groove 11b provided in the lower cassette case 3 around the pair of left and right back cover support shafts 10a, 10b. The state shown in FIGS. 4 to 7 is obtained.

Here, the groove shape of the left and right guide grooves 11a, 11b is the rotation when the back cover 10 is rotated by a certain amount about the pair of left and right rotation support shafts 10a, 10b provided on the same straight line. The guide pins 10c and 10d on the left and right have different positions from the support shafts 10a and 10b, and the locus is on either side of the guide grooves 11a and 11b.
Even if is regulated, the tip 10f of the back cover 10 draws the same locus.

In this way, the back lid 10 opens and closes the notch 12 on the back surface of the magnetic tape 5 by the bracket portion 6d of the front lid 6 and the rib 10e as the front lid 6 rotates.

Further, at the same time when the front cover 6 and the rear cover 10 are opened and closed, a reel brake releasing member (not shown) installed in the VTR enters the reel brake releasing hole 25 to stop the rotation of the cassette reels 4a and 4b. The reel brakes 21a, 21b that have been used are rotated in a direction of separating from the cassette reels 4a, 4b, and the restraint of the cassette reels 4a, 4b is released. Further, a reel stand (not shown) in the VTR supports the respective cassette reels 4a and 4b and becomes rotatable.

On the other hand, the light stand 14 for detecting the beginning and end of the magnetic tape 5 provided in the VTR enters the insertion hole 15. Also, magnetic tape 5
A loading post (not shown) for winding the magnetic tape around a rotating cylinder (not shown) enters the opening 8 of the tape cassette 1 and the magnetic tape 5 is projected to the front.
, During normal running, pull out in the tape path area 5a, 5b,
When running at high speed, pull out with 5c, 5d tape path Magnetic tape 5
Run. In this way, the magnetic tape 5 comes into contact with the guide posts 9a and 9b when the magnetic tape 5 is running at high speed or while the magnetic tape 5 is being pulled out. Therefore, in order to prevent damage to the magnetic tape 5 or to ensure the tape running performance with high accuracy, the guide posts 9a, 9b are required to have high accuracy with respect to environment / aging, wear, and surface roughness. It

The mounting operation when the tape cassette 1 is mounted in the cassette mounting position of the VTR has been described above, but the operation of taking out the tape cassette 1 from the VTR is completely opposite to the mounting operation.

In the first embodiment, only the guide groove 11a is attached to the guide post 9
The guide groove 1 was placed at a position where it did not overlap with a in the width direction A.
It may be 1b and the guide post 9b, or may be arranged at a position where neither of the guide grooves overlaps.

Further, the cutout portion 12 is also only the left end of the opening portion 8, but it is not limited to this.

As described above, according to the present invention, the magnetic tape is covered with the front lid and the back lid, and even in a tape cassette having a wide opening, a wide tape pass area is ensured and the running performance of the magnetic tape is further improved. The feature is that the reliability against tape damage is increased.

[Brief description of drawings]

FIG. 1 is a plan view with an upper cassette case and a front lid removed according to an embodiment of the present invention, FIG. 2 is a plan view with a back lid further removed, and FIG. 3 is a plan view of a tape cassette, FIG. 5, FIG. 5 is a sectional view of the tape cassette in the XX portion with the lid closed and opened, and FIGS. 6 and 7 are sectional views of the tape cassette in the YY portion with the lid closed and opened. FIG. 9 is a perspective view of a conventional tape cassette, FIGS. 9 and 10 are cross-sectional views of essential parts, and FIG. 11 is a plan view of essential parts of a lower cassette case. 1 ... Tape cassette, 2 ... Upper cassette case, 3 ...
… Lower cassette case, 5 …… Magnetic tape, 5a, b …… Tape path area, 5c, d …… Tape path, 6 …… Front lid, 8…
… Aperture, 9a, b …… Guide post, 10 …… Back cover, 10c…
… Left guide pin, 10d …… Right guide pin, 10e …… Rib,
11a …… Left guide groove, 11b …… Right guide groove, 12 …… Notch.

Claims (4)

[Claims] 1. A pair of tape reels around which a tape is wound and both ends of which are locked, a cassette case in which the tape is stretched on the front surface, and the pair of tape reels are built in, and a tape cassette is mounted on the front surface. An opening provided inside the stretched tape, a front lid that is pivotally supported on the side surface of the cassette case, and covers the front surface of the tape stretched on the front surface by rotation, and is pivotally supported by the front lid. A back cover that covers the back surface of the tape by rotation, and first and second grooves having different left and right groove shapes formed on the left and right side surfaces of the cassette case facing the opening that regulates the rotation of the back cover. A tape cassette having two guide grooves. 2. The tape cassette according to claim 1, wherein the first and second guide grooves are provided at positions different in distance from the front surface of the cassette. 3. A pair of tape reels around which a tape is wound and both ends of the tape are locked, a cassette case in which the tape is stretched on the front surface, and the pair of tape reels are built in, and a tape cassette is mounted on the front surface. An opening provided inside the stretched tape, a notch provided on a surface of the cassette case forming the opening, a shaft supported on a side surface of the cassette case, and stretched on the front surface. And a front lid that covers the front surface of the tape by rotation, and is pivotally supported by the front lid.
A tape cassette, comprising: a back cover that covers the back surface of the tape and the cutout portion by rotation, and a guide groove that restricts rotation of the back lid formed in the cassette case. 4. The tape cassette according to claim 2, wherein a guide member for guiding the tape stretched on the front surface and a notch portion of the cassette case are provided in the vicinity of the guide member.