JPH0135311Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a cassette cover opening mechanism in which a cassette holder loaded with a cassette is moved horizontally and lowered to bring the cover into contact with an opener at a predetermined position to open the cassette cover. .

[Technical background of the invention]

A cassette for a video tape recorder has a cover over the part where the tape is pulled out from the cassette half in order to protect the tape, which is the recording medium. This cover has a shaft protruding from its inner wall supported by the cassette half, is biased closed by a spring, and is furthermore locked to the cassette half to prevent it from opening. Usually, the cover is opened by unlocking it and then rotating it around its axis.
There are currently two methods for this. In the first method, the cassette is inserted into the cassette holder from the top of the video tape recorder, and the cassette holder is pushed down so that the cover comes into contact with the opener. Another method is to insert the cassette horizontally from the front of the videotape recorder, loading the cassette into a cassette holder, which moves horizontally and lowers so that the cover abuts the opener. In either method, after the cover is opened, the tape is pulled out from the cassette half and loaded. The latter method is especially called the front loading method.
The present invention relates to this type of scheme.

FIG. 1 is a simplified diagram of a conventional cassette cover opening mechanism, and this diagram will be explained below.

When the cover 2 of the cassette 1 is inserted in the direction of the arrow, the cassette 1 is loaded into the cassette holder 3. At this time, the cover 2 of the cassette 1 touches the protrusion 4 of the cassette holder 3 and is unlocked. At the same time, the motor 5, which is the power source of the moving means, is turned on. The rotation of the five shafts of the motor is decelerated by two gears 6a and 6b, and the large gear 6b rotates in the direction of the arrow. gear 6b
As the slider 8 rotates, the eccentrically connected crankshaft 7 moves the slider 8 in the depth direction along the upper surface of the guide plate 9. The slider 8 and the cassette holder 3 have two links 10 as shown in the figure.
Since they are connected by a and 10b, they move in conjunction with each other.
However, since this cassette holder 3 has a guide pin 11 fixed to its side surface that fits into a hook groove 12 provided on the side surface of the guide plate 9, the cassette holder 3 first moves horizontally and then descends as shown by the arrow in the figure. do.

When the cassette holder 3 moves horizontally, the cassette 1 loaded in the cassette holder 3 moves to the second
The cover 2 is moved to the position shown by the two-dot chain line in the figure, and the cover 2 is directly above the opener 13 in a predetermined position. A gap A is provided between the tip of the opener 13 and the lower edge of the cover 2, as shown in the figure. The cassette holder 3 is lowered by an amount A from the above position, and the lower edge of the cover 2 comes into contact with the tip of the opener 13. Furthermore, the cassette holder 3 descends,
As shown in FIG. 3, the cover 2 rotates around the axis and opens. Then, when the cassette 1 is lowered by a distance B from the tip of the opener 13, the cover 2
opens completely. This operation is performed by half a rotation of the large gear 6b, and by the second half rotation, the cassette holder 3
is returned to its original state.

[Problems with background technology]

In the conventional cassette cover opening mechanism, the cover was opened by rotating it around the axis using only the difference B between the height of the tip of the opener and the descending distance of the cassette holder.

However, with this method, the extent to which the cover opens becomes smaller as the cassette holder descends, so it is necessary to increase the descending distance (A+B) of the cassette holder in order to completely open the cassette cover.

Video tape recorders that adopt the front loading system have various advantages because the cassette is inserted from the front, but they have the disadvantage that the height of the video tape recorder cannot be lowered with the built-in conventional cassette cover opening mechanism. It was hot.

Another disadvantage of this cassette cover opening mechanism is that when the cassette holder descends and the center of rotation of the cover is below the tip of the opener, the reaction force of the opener becomes large and the cassette setting position shifts. It was hot.

[Purpose of invention]

The present invention was developed based on the above-mentioned drawbacks, and its object is to provide a cassette cover opening mechanism that is thin and does not cause the cassette to shift.

[Summary of the invention] Among the cassette cover opening mechanisms, the present invention is particularly characterized by the structure of the opener.

The opener according to the present invention has a contact member that comes into contact with a corner of the cover on the cassette half side and slides on the corner. This contact member is at a height such that it abuts the corner of the cover when the cassette holder is lowered and the corner of the cover rotates to some extent. In this case, the most desirable height of the contact member is such that a straight line connecting the center of rotation of the cover and the corner comes into contact with the corner when the cover is rotated beyond the vertical direction. However, it is not necessarily limited to this. This problem can be solved by making the part that first comes into contact with the corner part a slope.

When the cassette holder is lowered and the lower edge of the cover abuts the tip of the opener, the lower edge of the cover is maintained at its height by the opener. On the other hand, since the cassette half descends together with the cassette holder, the cover rotates around its axis and opens. Then, the corner portion of the cover rotates while descending and comes into contact with the contact member. The corners of the cover are maintained at their height by the contact members and slide over the contact members as the cassette half is lowered. At this time, the cover further rotates around the axis and the lower edge of the cover comes off the tip of the opener. The cassette holder then lowers a certain distance and the cover opens completely.

As described above, in the present invention, the opener is provided with a contact member to increase the opening degree of the cover relative to the descending distance of the cassette holder, thereby making it possible to shorten the descending distance of the cassette holder. Further, since the corner portion of the cover slides on the contact member and releases the reaction force of the opener, the cassette does not become misaligned.

[Example of idea]

FIG. 4 shows an opener which is a main part of the present invention, and will be specifically explained below with reference to this figure.

The opener 23 is a plate-shaped member, which is placed at a predetermined position on the base (the same position as in the conventional case).
The opener 23 has a contact member 24, which is formed by horizontally bending a portion of the opener 23 outward. Contact member 24
is at a height at which it just contacts the corner 2a of the cover 2 when the cassette 1 is lowered from the position shown by the solid line to the position shown by the dashed-dot line in FIG. 5 and the cover 2 is slightly opened. That is, this is the height at which the cover 2 contacts the tip of the opener 23 and opens, and the straight line connecting the rotation center of the cover 2 and the corner exceeds the vertical direction. The contact member 24 has a length that allows the corner 2a of the cover 2 to slide on the surface of the contact member 24. Note that the contact member 24 is the opener 23
It is also possible to provide them separately, rather than integrally with them.
Further, the contact member 24 that comes into contact with the corner portion 2a does not necessarily have to be planar.

Next, the operation when the cover 2 is opened by the opener 23 will be explained (see FIG. 5).

The cassette holder 3 is moved horizontally by the above-mentioned moving means, and the cover 2 of the cassette 1 is
is moved directly above the opener 23, that is, to the position shown by the solid line in FIG. At this time, as described above, there is a gap A between the lower edge of the cover 2 and the tip of the opener 23.

Next, the cassette holder 3 is lowered by the moving means, and the cassette 1 is lowered from the position shown by the solid line to the position shown by the dashed-dotted line. During this time, cover 2
The lower edge of the cover 2 is in contact with the tip of the opener 2.
rotates around the axis and opens, and the corner 2a of the cover 2 comes into contact with the contact member 24 at the position indicated by the dashed line. The cassette 1 is continuously lowered further from the position indicated by the one-dot chain line, and the corner portion 2a slides on the contact member 24. At this time, the cover 2 rotates around the axis and comes off from the tip of the opener 23. Furthermore, the cassette 1 is lowered to the position indicated by the two-dot chain line, and the cover 2 is completely opened. This state is shown in FIG. 6, and as can be seen from this figure and FIG. 5, the lower edge of the cover 2 is raised above the tip of the opener 23 by an amount C. Since the descending distance of the cassette holder is shorter by C than the conventional one, the cassette cover opening mechanism can be made thinner by C.

Further, as can be seen from FIG. 5, the corners of the cover slide on the surface of the contact member and no extra force is applied, so that the cassette does not become misaligned.

[Effect of idea]

As explained above, according to the present invention, the cassette cover opening mechanism can be made thin and the positional displacement of the cassette can be eliminated.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a conventional cassette cover opening mechanism, FIGS. 2 and 3 are operational illustrations,
FIG. 4 is a perspective view showing the main parts of the present invention, and FIGS. 5 and 6 are operational illustrations. 1...Cassette, 2...Cover, 2a...Corner, 3...Cassette holder, 4...Protrusion, 5...
...Motor, 6a, 6b...Gear, 7...Crankshaft, 8...Slider, 9...Guide plate, 10
a, 10b...link, 11...guide pin, 1
2... Hook groove, 13, 23... Opener, 24...
...Contact member.

Claims (1)

[Claims for Utility Model Registration] A cassette cover opening mechanism in which a cassette holder loaded with a cassette is moved horizontally by a moving means and lowered, and the cassette cover is brought into contact with an opener at a predetermined position to open the cassette cover, The opener operates when the cassette holder descends and the corner of the cover rotates to some extent.
A cassette cover opening mechanism characterized by having a contact member that comes into contact with this corner and slides on this corner.