JPS6258452A - Shutter opening and closing mechanism for magnetic disc cassette - Google Patents

Abstract

PURPOSE:To surely open and close a shutter with a very simple structure by fixing one end of a leaf spring to a cassette holder and forming a spring piece in its free end and providing this spring piece with a friction member and allowing this friction member to act upon the shutter. CONSTITUTION:When a shutter 7 is locked by a lock lever 67 and a cassette is inserted to a cassette holder 80 in this state, a friction member 82 rides on a slope 69 in the front end of a groove 8 of a cassette, and a free end 81f is brought into contact with the inside of a stopper 80e to press the friction member 82 more strongly in the direction of an arrow D through a spring piece 81f is pushed outward. When the cassette is inserted furthermore, the friction member 82 rides on the side face of the shutter 7. When insertion of the cassette is advanced furthermore, a claw 72 is disengaged from a notch part 67a to release the lock because a claw 80d starts to push the lock lever 67, and the shutter 7 is opened by the friction member 82 without pushing the shutter by the claw 80d because the force of friction stronger than the pressing force to the shutter 7 acts by the friction member 82.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a shutter opening/closing mechanism for a magnetic disk cassette, and more particularly to a shutter for a magnetic disk cassette in which no urging force is applied in the closing direction of the shutter. This relates to an opening/closing mechanism.

[Prior Art] Some magnetic disk cassettes have a structure in which a shutter is closed to close an opening into which a magnetic head or the like is inserted when not in use.

The shutters of this type of magnetic disk cassette include those that are always biased in the closing direction by a spring or the like, and those that are not biased.

Figure 3 shows a shutter opening/closing mechanism in which the shutter is not biased in the closing direction by a spring or the like.
It is shown in FIG.

FIG. 3 illustrates a magnetic disk cassette. A magnetic disk 1 is rotatably housed in a magnetic disk cassette 2 made of plastic or the like.

A center hub 3 is fixed to the center of the magnetic disk 1, and faces into an opening 5 formed in the center of the cassette.

A PG pin 4 for indicating the rotational phase of the disk is embedded in the center hub 3.

Openings 6 into which a magnetic head or the like is fitted are formed in the upper and lower side surfaces of the magnetic disk cassette 2.

This opening 6 is opened and closed by a shutter 7 that is slidably fitted from the side edge of the cassette so as to sandwich the top and bottom of the cassette.

This shutter 7 is slidable in the P and Q directions as shown by arrows.

A long and narrow opening 7a is formed at the side edge of the shutter 7.

Further, a groove 8 is formed in the cassette at the side edge on the side where the shutter 7 is provided.

At a predetermined position of the magnetic disk cassette 2, there is a through hole 9 for positioning when the magnetic disk cassette 2 is installed in the device. lO is formed.

Note that in FIG. 3, arrow C indicates the mounting direction of the cassette.

On the other hand, the opening/closing mechanism of the shutter is shown in FIGS. 4(a) to 4(e).

A shutter opening member 73 and a shutter closing member 74 are provided on the cassette holder side (not shown). The opening member 73 is formed of a leaf spring, for example, and is fixed to the upper surface of the cassette holder at its tail end, and has a claw 73a having a U-shaped cross section downwardly formed at its distal end.

Further, a bent portion 7 is provided on the side edge of the opening member 73 toward the upper side.
3c is formed, and a projecting piece 73e is provided on the upper surface of the distal end portion of the opening member 73 to protrude.

On the other hand, the closing member 74 is stacked on top of the distal end of the opening member 73, and one end thereof is slidably and rotatably connected to a pin 76 protruding from the opening member 73 through an elongated hole 74b. It is mounted on a shaft.

In the vicinity of the elongated hole 74b of the closing member 74, a claw 74a for closing the shutter is formed downward and folded back toward the back side of the opening member 73.

One side edge of this claw 74a, that is, the side edge on the side into which the cassette is inserted, is sloped.

Further, a bent portion 74c is formed upwardly on the side edge of the closing member 74 opposite to the elongated hole 74b.

A spring 77 is stretched between the bent portion 74c and the bent portion 73c of the opening member 73, and the opening member 74 is rotated clockwise in the middle diameter direction in FIG. Gives rotational habit.

Further, a notch 74d is formed on the side edge of the closing member 74 on the protruding piece 73e side, and this notch 74d and the protruding piece 7
3e and restricts the rotation limit of the closing member 74 in the counterclockwise direction.

Further, the side edge of the notch 74d on the bent portion 74c side is a slope 74.
It is e.

The opening/closing mechanism having the above-described structure has claws 73a and 74.
The cassette is attached to the apparatus side with the cassette facing a position corresponding to the groove 8 formed on the side edge of the cassette.

Furthermore, a claw 72 facing toward the groove 8 is formed on the shirt tough provided slidably on the cassette 2 at a position closer to the front in the mounting direction than the opening 7a.

Furthermore, a lock lever 67 made of synthetic resin or the like is provided on the cassette 2 side, and its base end is connected to the cassette 2.
It is fixed to a holding part 68 formed on the side.

In addition, the tip of the lock lever 67 is a free end,
The claw 72 is fitted into a groove 67a formed on the outer edge of the shutter 7, thereby locking the shutter 7.

FIG. 5(a) before mounting the cassette.

As shown in (b), the pawl 72 is connected to the groove 67 of the lock lever 67.
a, the shutter 7 is in a locked state, and the opening 6 is closed.

Next, the opening/closing operation of the shutter will be explained.

First, when the cassette 2 is mounted on the apparatus side, the claws 74a and 73a of the opening/closing mechanism relatively approach the tip 70a of the shutter 7 while being fitted into the groove 8.

Then, the slope of the claw 74a comes into contact with the tip 70a of the shutter 7, and the closing member 74 moves in the direction of arrow F around the bottle 76.
That is, it is rotated clockwise in FIG. 4(a) against the tensile force of the spring 77.

Then, it rides on the side of the shutter 7.

During this operation, the claw 74a does not come into contact with the a rough lever 6f, and the shutter 7 remains locked.

As the cassette is further inserted, the claw 74a is eventually fitted into the opening 7a by the force of the spring 77.

On the other hand, at about the same time, the claw 73a of the opening member pushes the lock lever 67 as shown in FIG.

Further, at the same time as the lock is released, the claw 73a contacts the tip 70a of the shutter 7, and as the cassette is mounted, the claw 73a contacts the tip 70a of the shutter 7, and as the cassette is installed,
) The shutter is opened reliably as shown in ().

Usually, a spring is provided on the ceiling of the holder to press the inserted cassette downward. Further, the height inside the holder is greater than the thickness of the cassette.

The holder is lowered and the cassette is positioned by the positioning bin. In this case, the positioning bin also determines the height of the cassette, while the holder is used to determine the exact position and height of the cassette. Even after it engages with the bin and stops, it descends a little, and at this time the cassette is urged downward by the above-mentioned pressing spring, ensuring the cassette positioning.

This is called overcharging, and overcharging begins from this state, and since the opening/closing mechanism is provided in the holder, during this overcharging, the cassette is still lowered together with the holder relative to the stopped cassette. Therefore.

There is a risk that the opening/closing claw, cassette, and shutter may be damaged.

Therefore, the fear of such damage is avoided by making the opening member made of a leaf spring and fixing its tail end to the holder so that it can swing up and down.

On the other hand, the shutter closing operation is performed as follows.

When the cassette is pulled out from the state shown in Fig. 5(d), the claw 7
4a is in the opening 7a and hits the edge 7b thereof, keeping the shutter 7 in that position against the withdrawal movement of the cassette, and the shutter.

7 is started to close.

Eventually, the claw 73a pushes the lock lever 67.

The state shown in FIG. 5(C) is reached, and the claw 72 eventually fits into the notch 67a, and locking by the lock lever 67 is performed.

As the cassette ejecting operation progresses further, the claw 7
4a, the closing member 74 is pulled in the cassette removal direction, and the bottle 76 moves to the right end in the elongated hole 74b.

As a result, the slope 74e and the protrusion 73e begin to come into contact with each other, and the closing member 74 is rotated in the direction of arrow F in FIG.
4a leaves the opening 7a.

The shutter is opened and closed as described above.

[Problems to be Solved by the Invention] When the above-described structure is adopted, the number of parts is extremely large, and the overall weight becomes large, which hinders miniaturization and weight reduction.

Furthermore, if a mechanism is provided to prevent damage to the shutter opening/closing mechanism due to overcharging of the cassette holder (not shown) when the cassette is attached, the structure will become even more complicated, and the structure will become larger and heavier.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention fixes one end of the leaf spring to the cassette holder, and further forms a spring piece on the free end side of the leaf spring. A structure was adopted in which a friction member is provided in the shutter, and this friction member is applied to the shutter to open and close the shutter using the frictional force.

[Function] When the above-described structure is adopted, the shutter is opened and closed by the frictional force of the friction member, and the relative positional shift of the cassette when the cassette holder is overcharged can be absorbed by the leaf spring and spring piece. can.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

1 and 2 illustrate one embodiment of the present invention, and the same parts as in FIGS. 3 to 5 are designated by the same reference numerals.
The explanation will be omitted.

In FIG. 1, the reference numeral 80 indicates a cassette holder, and guide portions 8 for guiding the cassette are provided at both left and right ends of the cassette holder.
0a is formed.

Further, on the upper surface of the cassette holder 80, a pair of left and right protrusions 80b and a screw hole 80c formed between the protrusions 80b are provided in line with the insertion direction of the cassette.

Further, among the guide parts 80a of the cassette holder 80, a claw 80d and a stopper 8 are provided on the guide part on the side where the shutter is inserted.
0e is formed.

On the other hand, one end of a leaf spring 81 is fixed to the upper side of the force set holder 80.

A through hole 81a is formed in this plate spring 81 at a position corresponding to one of the protrusions 80b, and the other protrusion 80b and screw hole 80
A long hole 81b is formed at a position corresponding to c.

The purpose of forming the long holes in this way is to absorb processing errors.

This leaf spring 81 is attached to the cassette holder 8 by a screw 81c.
Fixed above 0.

On the other hand, a protruding portion 81d is provided on the free end side of the leaf spring 81, and a bent portion 81e is formed at the tip thereof.

This bent portion 81e is located outside the guide portion 80a of the cassette holder.

Furthermore, an elongated spring piece 81f is continuously provided from the bent portion 81e toward the insertion direction of the cassette.

In the middle of this spring piece 81f there is a bent part 81g that goes inward.
A friction member 82 made of an elastic material such as rubber is fixed inside the bent portion 81g.

The left and right sides of this friction member 82 are inclined surfaces.

Moreover, the free end 81h of the spring piece 81f is located inside the stopper 80e.

Further, the friction member 82 is attached to the guide portion 80 of the cassette holder 80.
It is fitted inward from the opening 80f formed in a.

Note that the thickness of the friction member 82 is larger than the width of the groove 8 formed on the side edge of the cassette.

Next, the opening/closing operation of the shutter using the opening/closing mechanism as described above will be explained based on FIGS. 2(a) to 2(C).

When the shutter 7 is inserted into the cassette holder 80 with the shutter 7 locked by the lock lever 67, the friction member 82 rides on the slope 69 formed on the tip side of the groove 8 of the cassette, and the cassette straddles the groove 8. The friction member 82 rides on the side edge.

Then, the spring piece 81f is pushed outward, but the free end 81h contacts the inside of the stopper 80e and the friction member 82
This means pressing more strongly in the direction of the arrow.

If another cassette is inserted in this state, the friction member 82
gets on the side of the shutter 7.

□ Then, as the cassette is inserted further, the claw 80d starts to push the lock lever 67, so the claw 72 moves into the notch 67a.
The lock will be released.

When the lock is released, the shutter 7 is moved by the friction member 82.
Since the pressing force is large and an even larger frictional force is acting, the shutter 7 is opened by the friction member 82 even if the shutter is not pushed by the claw 80d.

Note that the distance between the friction member 82 and the pawl 80d is the same as that of the opening 7.
The friction member 82 does not fit into the opening 7a because it is smaller than the distance between the end Ii70a of the shutter and the end Ii70a of the shutter.

Therefore, an opening is not required on the shutter 7 side, but an existing cassette with an opening can be used as is as long as the above-mentioned dimensional relationship is maintained.

The state shown in FIG. 2(c) is a completely opened state.

Overcharging begins from this state, and since the opening/closing mechanism is provided in the holder, during this overcharging, the cassette is still lowered together with the holder relative to the stopped cassette.

Therefore, there is a risk that the opening/closing pawl, cassette, and shutter may be damaged. However, in this embodiment, this can be sufficiently absorbed by the elastic deformation of the spring piece at the tip of the leaf spring.

On the other hand, although the closing operation of the shutter is completely opposite to the operation described above, the shutter 7 is also closed by the frictional force of the friction member 82 at this time.

Then, the claw 72 is fitted into the notch 67a of the lock lever 67, and the locking is completed, and the friction member 82 is moved to the shutter 7.
It slides down, hits the side of the cassette, and eventually the cassette is pulled out completely.

On the other hand, the cassette holder is positioned at the position for recording and playing the cassette after the cassette is completely inserted.
A so-called overcharging operation is performed in which the whole is lowered and positioned.

At this time, a relative displacement of the cassette occurs within the cassette holder 80, but this displacement is absorbed by the deflection of the entire leaf spring 81.

[Effect] As is clear from the above description, according to the present invention, a spring piece is provided as a part of the leaf spring provided on the cassette holder, and a friction member that acts on the shutter is provided on this spring piece. Because of this, the shutter can be reliably opened and closed with an extremely simple structure by utilizing the frictional force of the friction member and the spring force of the spring piece.

[Brief explanation of drawings]

1 and 2 illustrate one embodiment of the present invention, FIG. 1(a) is an exploded perspective view of the main parts, FIG. 1(b) is a perspective view of a spring piece, and FIG. (a) to (C) are diagrams for explaining the operation, Figure 3 is a perspective view of the cassette, Figures 4 (a) to (e) are for explaining the conventional opening/closing mechanism, and Figure (a) is a plan view. , Figure (b) is a right side view, Figure (C) is a left side view, Figure (d) is a left side view.
) is a front view, (e) is a rear view, and Figures 5 (a) to (d) are
) is an operation explanatory diagram. 2...Magnetic disk cassette 7...Shutter 67...Lock lever 72
...Claw 80- Cassette boulder 81...
- Leaf spring 81f...Spring piece 82...Friction member (b) Fig. 2fl Figure 1 (b) Rizo/Ito/1 Shikuanaita Figure 3 F (a) (b) Figure 4 2≦! Daiishi Sukuae Yahi Tsutsu Figure 5 (CI) Figure 5 (C)

Claims (1)

[Claims] 1) One end of a leaf spring is fixed to the cassette holder, and a spring piece extending along the side edge of the cassette holder is provided on the free end side of the leaf spring, and this spring piece has friction with the shutter of the cassette. A shutter opening/closing mechanism for a magnetic disk cassette, characterized in that an engaging friction member is provided. 2) The shutter opening/closing mechanism for a magnetic disk cassette according to claim 1, wherein the thickness of the friction member is equal to or greater than the thickness of the cassette. 3) A shutter opening/closing mechanism for a magnetic disk cassette according to claim 1 or 2, characterized in that a stopper for locking the free end side of the spring piece is provided on the cassette holder side.