JPH06150609A - Disk cartridge - Google Patents

Abstract

PURPOSE:To improve a characteristic of impact resistance strength for a shutter lock member and/or an erroneous recording preventive member while maintaining the sliding performance and elastic displacement performance. CONSTITUTION:By a disk cartridge, a disk shaped information recording medium 4 is freely rotatably housed inside the main body 1 of cartridge. In this disk cartridge, the shutter lock member 20 and/or the erroneous recording preventive member 39 freely operably incorporated inside the main body 1 of cartridge are molded by a polyacetal resin or a polycarbonate resin, in which a polyurethane resin is mixed by weight >=5%, <=30%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc cartridge in which a disc-shaped information recording medium such as an optical disc is rotatably housed inside a cartridge body, and in particular, an opening for recording and reproducing information signals is opened. , A shutter lock member for holding the shutter member to be closed at the opening closed position and / or a re-recording of an information signal with respect to the information recording medium.
Position to prevent erasure of information signal once recorded
And an erroneous recording prevention member selectively moved to the position of.

[0002]

2. Description of the Related Art An information signal such as a musical tone signal or a video signal is produced by using a laser beam having a very small spot on a disc substrate formed of a synthetic resin material such as a light-transmitting acrylic resin, a polycarbonate resin or the like, glass or the like. Is an optical disc, a magneto-optical disc (hereinafter collectively referred to as an optical disc) capable of recording recorded information signals at high density and reading the recorded information signals and rewriting the recorded information signals. It is widely used in video disk systems and office office equipment.

In this optical disc, if dust adheres to the surface or is scratched, the information signal cannot be read. For this reason, a cartridge main body is constructed by combining an upper half and a lower half of a rectangular shallow dish formed of synthetic resin, and an optical disc is rotatably accommodated in the cartridge main body to construct a disc cartridge. An information signal recording / reproducing opening for exposing at least a part of the optical disk to the outside in the radial direction is formed in the cartridge body, and the information signal recording / reproducing opening is opened or closed. In this way, the shutter member is movably assembled to the cartridge body.

Further, the disc cartridge is provided with a shutter lock member which is rotatably supported by the cartridge main body and holds the shutter member at a position where the information signal recording / reproducing opening is closed. The shutter lock member is formed of a synthetic resin material, and is, for example, a lock arm which is thinly formed from one end of a base portion configured as an attachment portion and is curvedly formed through an elastic displacement portion capable of elastic displacement. The lock arm portion is provided with an engaging concave portion that is relatively engaged with the engaging piece of the shutter member at the top portion on the outer surface side.

In this shutter lock member, the through hole provided in the mounting portion is fitted to the mounting pin standing on the lower half so that the engaging concave portion faces the front surface of the cartridge main body. It is rotatably attached to the inner surface of the half. The shutter lock member is configured such that, when the shutter member is set and operated to close the information signal recording / reproducing opening, the engaging concave portion relatively engages with the engaging piece of the shutter member, so Holding the member locked in the open position.

When the disc cartridge is inserted into the cartridge mounting portion of the information recording / reproducing apparatus, the shutter releasing member of the information recording / reproducing apparatus is engaged with the shutter opening member insertion groove formed in the front side of the cartridge body. The shutter opening member rides from the outer side surface of the lock arm portion of the shutter lock member toward the front end side to elastically displace the elastically displacing portion so that the lock arm portion is inside the cartridge main body. Press in one direction. As a result, the engagement between the engagement piece of the shutter member and the engagement recess of the shutter lock member is released, and the shutter member is pushed by the shutter opening member and moved in the direction to open the information signal recording / reproducing opening. It

On the other hand, the disc cartridge is provided with an erroneous recording prevention mechanism in order to prevent the information signal once recorded on the optical disc from being accidentally erased. This erroneous recording prevention mechanism is configured so that it can be selectively moved between a first position that enables re-recording of an information signal on an optical disc and a second position that prevents erasure of a recorded information signal. For example, an erroneous recording prevention member that opens and closes an erroneous recording detection hole formed in the corner portion of the lower half is movably assembled to the cartridge body.

The erroneous recording preventing member is made of a synthetic resin material and has an erroneous recording preventing portion having a size large enough to close the erroneous recording detecting hole formed in the lower half. The first and second elastic arm portions are configured to extend so as to face each other from both end sides on one end side of the section. The erroneous recording prevention member is erected on the lower half and is interposed between the pair of guide walls having the first and second engaging recesses formed therein. A first position for opening the erroneous recording detection hole and a second position for closing the erroneous recording detection hole by engaging engagement protrusions formed at the tips respectively with the first and second engagement recesses.
The position of and is moved to.

Therefore, at the first position where the erroneous recording preventing member opens the erroneous recording detecting hole, the erroneous recording detecting means provided on the information recording / reproducing apparatus side enters the erroneous recording detecting hole and detects it. Then, the recording of the information signal on the optical disc housed in the cartridge body is prohibited.

[0010]

By the way, the shutter lock member or the erroneous recording prevention member movably incorporated in the cartridge main body prevents shavings from being generated during the moving operation, and has a sufficient elastic displacement. In order to make it possible, it is generally molded with a polyacetal resin, a polycarbonate resin or the like which is excellent in sliding characteristics and elastic displacement characteristics. However, the polyacetal resin has a characteristic that the impact strength is slightly small, and therefore, if the shutter lock member molded with this polyacetal resin accidentally drops the disc cartridge, it is formed thinly from one end of the base, for example. As a result, the tip of the curved lock arm portion may be damaged via the elastically displaceable portion.

Therefore, a broken piece of the lock arm portion of the shutter lock member damages the optical disk, or the shutter member cannot be locked, and dust or the like enters the cartridge body through the information signal recording / reproducing opening. However, there arises a problem that the reading and recording of the information signal are disabled by permitting the above.

Similarly, in the erroneous recording prevention member, the tips of the first and second elastic arm portions formed so as to face each other from one end side of the erroneous recording prevention portion are damaged, There is a possibility that the broken pieces may damage the optical disk, or the erroneous recording detection hole may not be opened or closed by the erroneous recording prevention member, and valuable information signals may be erased.

Therefore, the present invention is required for these members by molding a shutter lock member and / or an erroneous recording prevention member operably incorporated in the cartridge body by using a synthetic resin mixed with a polyurethane resin as a material. It is intended to provide a disc cartridge which improves the impact strength property while maintaining the sliding property and the elastic displacement property, thereby reliably protecting the optical disc and / or preventing erroneous erasure of information signals. It was proposed for the purpose.

[0014]

DISCLOSURE OF THE INVENTION A disk cartridge according to the present invention which achieves this object is a disk cartridge in which a disk-shaped information recording medium is rotatably housed inside a cartridge body. A shutter lock member and / or an erroneous recording prevention member operably incorporated in the main body is formed by using a synthetic resin in which a polyurethane resin is mixed in a weight ratio of 5% to 30%.

[0015]

According to the present invention, the polyurethane resin is added in a weight ratio of 5
% And 30% or less, a shutter lock member and / or an erroneous recording prevention member formed by using a synthetic resin as a material has a sliding characteristic for the operation such as rotation and movement in the cartridge body, or a shutter member, The elastic displacement characteristics during the engagement operation with the shutter release member, the guide wall, etc. are sufficiently maintained, and the impact resistance characteristics are improved, and even when the disk cartridge is dropped, the parts constituting these members are damaged. Is prevented.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, a disk cartridge provided with a shirt lock mechanism and an erroneous recording prevention mechanism according to the present invention has a substantially shallow plate-shaped upper half 2 and a lower half formed by a synthetic resin material. The cartridge body 1 is a combination of the cartridge body 1 and the cartridge body 1.
An optical disc 4, which is a disc-shaped information recording medium, is rotatably accommodated therein.

On the outer peripheral portions of the upper and lower halves 2 and 3, rising peripheral walls 5a and 5b which are abutted against each other and constitute an outer peripheral wall 5 of the cartridge main body 1, are erected. The inner surfaces of the halves 2 and 3 facing each other are formed as arc walls inscribed in the rising peripheral walls 5a and 5b,
Disc storage portion forming walls 6a and 6b that are abutted against each other to form a disc storage portion, and a plurality of butt fitting protrusions 7a and 7b are provided upright.

Therefore, the upper and lower halves 2 and 3 are formed by the rising peripheral walls 5a and 5b and the disc storage portion forming walls 6a and 6 respectively.
The cartridge main body 1 is constructed by assembling the butt-fitting b and the butt-fitting projections 7a and 7b, and integrating them by ultrasonic welding or the like.

A circular opening 8 is formed in a substantially central portion of the lower half 3 and is accommodated in the cartridge main body 1 when the disc cartridge is mounted on the information recording / reproducing apparatus. The disc table of the information recording / reproducing apparatus for driving the optical disc 4 thus operated functions as a disc entrance opening. Specifically, the disk-entry opening 8 exposes the metal plate 9 for magnet clamping, which is provided by closing the center hole of the optical disk 4 housed in the cartridge body 1.

The upper and lower surfaces of the cartridge main body 1, that is, the upper and lower halves 2 and 3, face at least a part of the signal area formed on the optical disk 4 housed outside to the outside. The information signal recording / reproducing openings 10 and 11 are provided so as to face each other, and the information signal recording / reproducing openings 10 and 11 are close to the disc entrance opening 8 as shown in FIG. It is formed in a rectangular shape extending from the position to the front side of the cartridge main body 1 and substantially at the center of the cartridge main body 1 in the left-right direction.

As shown in FIG. 2, on the front surface side of the cartridge main body 1, a shutter opening member 13 (FIG. 3) arranged on the recording / reproducing apparatus side for moving a shutter member 12 described later.
The shutter opening member insertion groove 14 into which the reference (see) enters is formed. The shutter opening member insertion groove 14 has an opening end 14a on one side surface orthogonal to the front surface of the cartridge body 1 and is formed in the movement direction of the shutter member 12, as shown in FIG. In addition, a shutter slide guide wall 15 which is provided upright on the inner side surface of the lower half 3 is provided in the shirt opening member insertion groove 14 in order to ensure stable operation of the shutter member 12. .

A butt wall 16 is erected on the inner surface of the upper half 2 on the front edge side of the information signal recording / reproducing opening 10. The butt wall 16 is formed by combining the upper and lower halves 2 and 3. In this state, the cartridge body 1 is abutted against the inner surface of the lower half 3 to prevent the cartridge main body 1 from bending in the thickness direction at the shutter opening member insertion groove 14.

In order to prevent dust and the like from entering the cartridge body 1 through the information signal recording / reproducing openings 10 and 11 and adhering to the housed optical disc 4,
A shutter member 12 for opening and closing the information signal recording / reproducing openings 10 and 11 is assembled. The shutter member 12 is formed by pressing a thin metal plate, and includes shutter portions 12a and 12b for opening and closing the information signal recording / reproducing openings 10 and 11, and a base of the shutter portions 12a and 12b. Connecting piece 12c for connecting the end sides
It consists of and, and has a U shape as a whole.

At both ends of the connecting piece 12c of the shutter member 12, the shutter member 12 has a U-shaped cross section having a height substantially corresponding to the height of the lower half 3 on the front surface side. First and second slide guide portions 17 and 18 are provided so as to guide in parallel stable movement along the front surface side. When the shutter member 12 is attached to the cartridge body 1 at the tip end side of the first slide guide portion 17, the shutter member 12 is inserted into the shirt opening member insertion groove 14 formed on the front side of the cartridge body 1, and An engagement piece 19 that is relatively engaged with a shutter lock member 20 arranged in the cartridge body 1 described later is formed by bending.

The shutter member 12 is fitted and disposed on the cartridge body 1 so as to sandwich the front side of the lower harf 3 by the first and second slide guide portions 17 and 18.
A closed position for closing the information recording / reproducing openings 10, 11.
It is assembled to the cartridge body 1 so as to be freely movable in two positions, that is, an open position where it is opened. The thickness of the shutter member 12 is approximately equal to the area extending from the peripheral edge of the information signal recording / reproducing openings 10 and 11 of the cartridge main body 1 to one side surface side and the area extending to the front surface side where the shutter member 12 moves. A shutter slide concave portion 21 having a depth is provided so that the shutter slide concave portion 21 allows the shutter member 12 to be mounted flush with the surface of the cartridge main body 1, thus increasing the thickness. It is prevented.

A shutter lock member 20 is attached to the cartridge main body 1 for holding the shutter member 12 in a closed position where the information signal recording / reproducing openings 10 and 11 are closed. The shutter lock member 20 is provided with a pivotal support portion 24 having a base end portion provided with an insertion hole 23 which is inserted into a support shaft 22 which is provided upright on the inner surface of the lower half 3 constituting the cartridge main body 1, and a shutter. A lock arm portion 26 having an engaging recess 25 with which the engaging piece 19 formed on the member 12 is engaged with each other.
And an elastic displacement portion 27 integrally extended from the pivot portion 24 so as to face the lock arm portion 26.

A lock door of the shutter lock member 20.
The cam portion 26 is formed in a substantially V shape with a bulged central portion, and an engaging recess 25 with which the engaging piece 19 formed on the shutter member 12 is relatively engaged is provided at the top of the central bulged portion. Has been done. In addition, as shown in FIG.
As shown in FIG. 5, the turning position regulating step portion 28 is formed by thinly notching the portion of the other side surface of the lock arm portion 26 from the tip to the base end. When the shutter lock member 20 is attached to the cartridge body 1, the rotation position regulation step portion 28 engages with a shutter lock member rotation regulation wall 29, which will be described later, formed on the inner surface of the lower half 3. The rotation position of the shutter lock member 20 is regulated. Further, the elastic displacement portion 27 of the shutter lock member 20.
An abutting portion 30 bulging in a semicircular cross section is formed at the free end of the.

A support shaft 22 of the lower half 3 is provided upright.
A shutter lock member rotation restricting wall 29, which engages with a rotation position restricting step 28 formed in a lock arm part 26 of the shutter lock member 20 in parallel with the shutter slide guide wall 15, is provided in the shutter portion 31. The elastic displacement portion 27 of the shutter lock member 20 is parallel to the lock member rotation restricting wall 29.
The abutment support wall 32, which abuts and supports the abutment part 30, the outer surface of the disk storage part forming wall 6b and the shutter lock member rotation restricting wall 29, and the shutter lock member 20.
Lock arm portion support wall 33 that supports the tip end side of the lock arm portion 26, and the contact support wall 32 that is located between the lock arm portion support wall 33 and the support shaft 22 and the shutter lock member rotation. A shutter lock member support wall 34 that connects with the regulation wall 29 is erected integrally with each other.

Further, as shown in FIG. 3, the region between the support shaft 22 of the corner portion 31 on which the support shaft 22 of the lower half 3 is erected and the shutter lock member support wall 34 is formed. Time,
It serves as an eject pin projecting portion 35 from which an eject pin for projecting the lower half 3 from the mold cavity is projected. Therefore, due to the ejection of the eject pin, a burr protruding from the surface of the lower half 3 is formed around the eject pin projecting portion 35, and this burr exists in the rotation region of the shutter lock member 20. However, the shutter lock member 20 has a proper gap between the shutter lock member support wall 34 and the inner surface of the lower half 3 and does not hinder its operation.

As shown in FIG. 3, the shutter lock member 20 has a rotation position restricting step portion 28 formed in a lock arm portion 26 in which an insertion hole 23 formed in a pivot portion 24 is inserted into a support shaft 22. By engaging the shutter lock member rotation restricting wall 29 and abutting and supporting the abutment portion 30 at the tip of the elastic displacement portion 27 on the abutment support wall 32, the corner portion in the lower half 3 is provided. 31 is provided.

As described above, the corner portion 3 of the lower half 3
The shutter lock member 20 disposed in the first
The arm portion 26 extends along the shutter opening member insertion groove 14 formed on the front side of the cartridge body 34, whereby the engagement recess 25 formed at the top of the lock arm portion 26 releases the shutter. The card faces the inside of the member insertion groove 14
A shutter member 1 that slides on the front side of the trunk body 1
The two engaging pieces 19 can be engaged with each other. Then, in the shutter member 12, in the normal state, the engagement piece 19 is engaged with the engagement recess 25 of the shutter lock member 20 to close the information signal recording / reproducing openings 10 and 11. Is held in a locked state.

When the embodiment disk cartridge having the shutter lock member 20 is inserted into the cartridge mounting portion of the information recording / reproducing apparatus according to the insertion direction indicating mark 36 provided on the upper surface of the cartridge body 1, A shutter opening / closing member insertion groove 14 formed on the front side of the cartridge body 1.
The shutter opening member 13 provided on the side of the information recording / reproducing apparatus enters into. Then, as the disc cartridge is inserted into the disc mounting portion of the information recording / reproducing apparatus, the shirt releasing member 13 is mounted from the outer side surface of the lock arm portion 26 of the shutter lock member 20 toward the front end side. Then, the lock arm portion 26 is pushed inwardly of the cartridge main body 1.

The lock arm portion 26 is the cartridge main body 1.
When the shutter lock member 20 is pressed inwardly, the shutter lock member 20 rotates in the clockwise direction in FIG. 3 about the pivotal support portion 24 pivotally supported by the support shaft 22, and contacts the contact support wall 32. The elastic displacement portion 27 with which 30 is brought into contact is elastically displaced. Due to the rotating operation of the shutter lock member 20, the engagement piece 19 of the shutter member 12 is released from the shutter lock member 2.
By releasing the engagement with the engagement recess 25 of 0,
You will be able to move freely.

When the disc cartridge is further inserted into the cartridge mounting portion after the shutter member 12 is free to move, the shutter member 12 is pressed by the shutter opening member 13 and the opening portion opening position. The shutters 12a and 12b open the closed state of the information signal recording / reproducing openings 10 and 11 of the cartridge main body 1. When the shutter member 12 slides to the opening opening position, the pressing operation of the lock arm portion 26 by the shutter opening member 13 is released, the elastically displaced portion 27 that has been elastically displaced elastically returns, and the shutter lock member 20 is released. Turning around the pivot 24 in the counterclockwise direction in FIG. 3, the engaging recess 2 is inserted into the shutter opening member insertion groove 14.
It will be in the state that 5 faced.

When the recording or reproducing operation of the information signal is completed and the ejecting operation of the disk cartridge is performed, the shutter member 12 is moved relative to the cartridge body 1 and moves toward the opening closing position. By the operation of the shutter member 12, the engagement piece 19 is climbed up on the guide surface provided at the tip of the lock arm portion 26 of the shutter lock member 20 in the state where the engagement piece 19 is rotated and returned.
The elastic displacement portion 27 of the shutter lock member 20 is elastically displaced. When the disk cartridge is further pulled out, the engagement piece 19 of the shutter member 12 and the engagement recess 25 of the shutter lock member 20 are engaged with each other, and the shutter member 1
Reference numeral 2 is held in a locked state at a position where the information recording / reproducing openings 10 and 11 are closed.

Lower half 3 constituting the cartridge main body 1
In the corner portion 37 in which the shutter lock member 20 is disposed and the corner portion 37 at the diagonal position sandwiching the disc table entry opening 8, the erroneous recording detection hole 38 and the erroneous recording prevention member are provided. An erroneous recording prevention mechanism including 39 is provided. The erroneous recording prevention member 70 is formed of a synthetic resin material, and as shown in FIG. 5, the erroneous recording has a substantially rectangular shape large enough to close at least the erroneous recording detection hole 38 formed in the lower half 3. The prevention portion 40, the first elastic arm portion 41 projecting from the central portion of the erroneous recording prevention portion 40, and the first elastic arm portion 41 are opposed to each other in parallel to both sides. It is composed of a second elastic arm portion 42 and an operation arm portion 43 that are integrally provided so as to project, and the overall shape is approximately E-shaped.

The first elastic arm portion 41 is formed to be longer than the second elastic arm portion 42 and the operating arm portion 43.
Further, the locking projections 4 are formed at the tips of the first arm portion 41 and the second arm portion 42 so as to project in opposite directions.
4, 45 are integrally formed. Since the first elastic arm portion 41 is formed to be long with respect to the second elastic arm portion 42, the locking convex portions 44 and 45 are arranged so as to mesh with each other. Further, the operation arm section 43
An operating portion 46 is integrally formed at the tip of the first and second elastic arm portions 41, 42 so as to project outward in the opposite direction.

An erroneous recording prevention portion 40 of the erroneous recording prevention member 39 is formed with an inclined guide surface 47, and this inclined guide surface 47 is engaged with a guide projection wall 48 erected on the lower half 3. Then, the erroneous recording prevention unit 40 guides the erroneous recording detection hole 38 so as to be surely closed.

A lower cover provided with the erroneous recording prevention member 39.
On the inner surface of the corner portion 37 of the frame 3, as shown in FIG. 6, the first and second elastic arm portions 41, 42 of the erroneous recording prevention member 39 are provided.
A slide guide wall 49 is integrally provided upright to guide the moving direction of the above and is sandwiched by the first and second elastic arm portions 41 and 42. The slide guide wall 49 is formed in parallel with the rising peripheral wall 5a of the lower half 3 and is provided with first and second click concave portions 50 and 51 which are curved outward. These first and second click recesses 50 and 51 are located at a first position where the erroneous recording prevention portion 40 of the erroneous recording prevention member 39 closes the erroneous recording detection hole 38 and a second position where the erroneous recording detection hole 38 is opened. When moved to the position, the engaging projections 4 of the second elastic arm portions 42 respectively.
5 is formed at a position where it can be engaged.

The rising peripheral walls 5a, 5b of the upper and lower halves 2, 3.
Are provided with notches 52a and 52b at positions corresponding to the corner portion 37 in which the erroneous recording prevention member 39 is disposed. These notches 52a and 52b are provided on the upper and lower halves 2, respectively.
Operation guide hole 5
Make up 3. The operation guide hole 53 is provided in the erroneous recording prevention member 3.
When the erroneous recording prevention unit 40 is moved to the first position where the erroneous recording detection hole 38 is closed and the second position where the erroneous recording detection hole 38 is opened, the operation unit 46 of 9 is exposed to the outside. It has a sufficient length.

By the way, the operation guide hole 53 is formed so that a gap is formed on the side wall orthogonal to the moving direction of the erroneous recording prevention member 39 in order to easily and accurately perform the above-described movement operation of the erroneous recording prevention member 39. It is configured. That is, the operation guide hole 53 has cutout recesses (54a, 54b), (5) on both side walls orthogonal to the moving direction of the erroneous recording prevention member 39, in other words, on both side walls in the longitudinal direction of the operation guide hole 53.
4c, 54d) respectively,
The operation guide hole 5 in which the length between the side walls of the outer opening is larger than the length between the side walls of the inner opening of the trunk body 1.
3 are configured.

As described above, the notch recesses (54a, 54b) formed on the both side walls in the longitudinal direction of the operation guide hole 47,
By (54c, 54d), a gap is formed between the operation guide hole 53 and both side surfaces of the operation portion 46 of the erroneous recording prevention member 39, so that the slide guide wall 49 is sandwiched between the first and the first portions. (2) The erroneous recording prevention member 39, which is firmly held by the elastic arm portions 41 and 42, can be easily and easily moved by inserting fingernails into these gaps without using an operating member such as tweezers. it can.

Located inside the operation guide hole 53, a shield wall 55 is formed upright on the inner surface of the lower half 3 in parallel with the slide guide wall 49. The shielding wall 55 regulates elastic displacement of the operation arm portion 43 of the erroneous recording prevention member 39 inward of the cartridge main body 1 and covers the operation guide hole 53 to allow the inside of the cartridge main body 1 to be seen through. regulate.

As shown in FIGS. 7 and 8, the erroneous recording prevention member 70 positions the erroneous recording prevention portion 40 on the side facing the erroneous recording detection hole 38, and the first and second elastic arm portions 41. , 42
With the slide guide wall 49 sandwiched between them, the operation arm portion 43 is arranged on the inner surface of the lower half 3 so as to extend between the rising peripheral walls 5a and 5b and the shielding wall 55. As a result, the erroneous recording prevention member 39 is slid by the operation portion 46 which is exposed to the outside on the back side of the cartridge body 1 through the operation guide hole 53.

The operation portion 46 of the erroneous recording prevention member 39
Has such a projecting dimension that it faces outward through the operation guide hole 53 so that the tip end surface of the lower half 3 is substantially flush with the side surface of the lower half 3 when assembled. Has been done.

The erroneous recording prevention member 39 is included in the erroneous recording prevention section 40.
Is at the first position where the erroneous recording detection hole 38 is closed,
As shown in FIG. 7, the engaging convex portion 45 at the tip of the second elastic arm portion 42 is relatively engaged with the first click concave portion 50 formed in the slide guide wall 49, so that the erroneous recording detection hole 38 is formed. It is held in a closed state. When the erroneous recording prevention section 40 closes the erroneous recording detection hole 38 in this way, for example, the erroneous recording detection means provided on the information recording / reproducing apparatus side is prevented from entering the erroneous recording detection hole 38, and the card is prevented. An information signal can be recorded on the optical disc 4 housed in the trunk body 1.

When the erroneous recording preventing member 39 is slid in the direction of arrow A in FIG. 7 and the erroneous recording preventing portion 40 is at the second position where the erroneous recording detecting hole 38 is opened, as shown in FIG. , A second click concave portion 51 in which the locking convex portion 45 at the tip of the second elastic arm portion 42 is formed in the slide guide wall 49.
By being relatively engaged with, the misrecording detection hole 38 is held in an open state. In this way, in the state where the erroneous recording prevention unit 40 opens the erroneous recording detection hole 38,
For example, an erroneous recording detecting means provided on the information recording / reproducing apparatus side enters the erroneous recording detecting hole 38 and prohibits recording of an information signal on the optical disc 4 housed in the cartridge body 1.

Further, the erroneous recording prevention member 39 is moved from the first position where the erroneous recording prevention section 40 closes the erroneous recording detection hole 38 to the second position where the erroneous recording detection hole 38 is opened, The locking convex portion 44 formed at the tip of the first elastic arm portion 41 moves by riding on the curved rear side wall of the first click concave portion 51, and the erroneous recording prevention portion 40 opens the erroneous recording detection hole 38. When it reaches the second position, it comes into pressure contact with the slide guide wall 49, thereby restricting the movement of the erroneous recording prevention member 39 in the first position direction.

By the way, as described above, the shutter lock member 20 holds the shutter member 12 at the two positions for opening and closing the information recording / reproducing openings 10 and 11, respectively. 22 at its pivotal branch 2
4 is swingably supported and the lock arm portion 26 is provided.
Is pressed by the shutter opening member 13, the elastic displacement portion 60 elastically displaces. On the other hand, erroneous recording prevention member 39
Also, the erroneous recording prevention section 40 moves the erroneous recording detection hole 38 to two positions for opening and closing, respectively, and
The second elastic arm portions 41 and 42 are elastically displaced to engage with the first and second click concave portions 50 and 51, respectively.

Thus, these shutter lock members 2
0 and the erroneous recording prevention member 39 are members that are moved in the cartridge body 1 and part of which is elastically displaced, so that they can be scraped and dusted during operation, and sufficient elastic displacement is possible. Of course, even if the disc cartridge is dropped, each component is formed of a synthetic resin material having a material property of impact resistance so as not to be damaged. That is,
The shutter lock member 20 and the erroneous recording prevention member 39 are formed of, for example, a synthetic resin material in which a polyacetal resin is used as a base material and a polyurethane resin is mixed in a weight ratio of 5% to 30%.

As described above, in the shutter lock member 20 and the erroneous recording prevention member 39 formed of the polyacetal resin obtained by mixing the polyurethane resin in the predetermined weight ratio, the conventional shutter lock member 20 made of the polyacetal resin and the erroneous recording are prevented. Compared with the prevention member 39, it has characteristics such as excellent impact resistance, good fluidity of resin, little retention discoloration, good heat stability, and little deposit during molding. .

[0052]

[Table 1]

Table 1 is a physical property comparison table between the test piece 1 formed of polyacetal resin and the test piece 2 formed of polyacetal resin formed by mixing 10% by weight of polyurethane resin. This table 1
As is apparent from the above, the test piece 2 is extremely superior to the test piece 1 in the characteristics relating to the mechanical strength against the impact such as dropping, that is, the tensile elongation and the Izod impact strength.

When molded with a polyacetal resin mixed with a polyurethane resin having a weight ratio of less than 5%, improvement in impact resistance cannot be expected, and the weight ratio is 30%.
When molded with a polyacetal resin mixed with a polyurethane resin exceeding 100, there is a problem that sliding characteristics are deteriorated, smooth operation may not be performed, and chipping is likely to occur.

In the above-described embodiment, the shutter lock member 20 and the erroneous recording prevention member 39 are formed of a synthetic resin material in which a polyacetal resin is used as a base material and a polyurethane resin is mixed in a weight ratio of 5% to 30%. However, in addition to the polyacetal resin, for example, even when molded by a synthetic resin material obtained by mixing a polyurethane resin with a polycarbonate resin in a weight ratio of 5% to 30%, in addition to the polyacetal resin,
Equivalent effect is achieved.

[0056]

As described above, according to the present invention, the shutter lock member and / or the erroneous recording prevention member is formed by the synthetic resin in which the polyurethane resin is mixed in the weight ratio of 5% to 30%. Therefore, the operating characteristics and elastic displacement characteristics of these members in the cartridge body are maintained at the same level as conventional ones, and the impact strength characteristics are improved, so if the disk cartridge is accidentally dropped. Even in such a case, it is possible to reliably prevent the inconveniences such as damage to the respective constituent parts of the member and damage to the optical disk due to the damaged pieces, or dust entering inside and adhering to the surface of the optical disk.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a disk cartridge according to the present invention.

FIG. 2 is a perspective view from the upper surface side of the disc cartridge.

FIG. 3 is a plan view of an essential part showing the disc cartridge except for an upper half.

FIG. 4 is a perspective view of a shutter lock member included in the disc cartridge.

FIG. 5 is a perspective view from the bottom side of the disc cartridge.

FIG. 6 is an essential part exploded perspective view showing an erroneous recording prevention mechanism provided in the disk cartridge.

FIG. 7 is a plan view of a main part for explaining the operation of the erroneous recording prevention mechanism section, showing a first state in which an erroneous recording detection hole is closed by an erroneous recording prevention member.

FIG. 8 is a plan view of relevant parts for explaining the operation of the erroneous recording prevention mechanism section, showing a second state in which an erroneous recording detection hole is opened.

[Explanation of symbols]

 1 ... Cartridge body 2 ... Upper half 3 ... Lower half 4 ... Optical disc 12 ... Shutter member 13 ... Shutter release member 20 ... -Shutter lock member 38 --- Error recording detection hole 39 --- Error recording prevention member

Claims (3)

[Claims] 1. A disk cartridge in which a disk-shaped information recording medium is rotatably housed in a cartridge body, wherein a movable member operably incorporated in the cartridge body is made of polyurethane resin. A disc cartridge formed by molding a synthetic resin mixed in a ratio of 5% to 30%. 2. The movable member is a shutter lock member for holding a shutter member for opening and closing an information signal recording / reproducing opening for exposing a part of the information recording medium to the outside at an opening closed position. Item 1. The disc cartridge according to Item 1. 3. An erroneous recording in which the movable member is selectively moved to a first position where the information signal can be re-recorded on the information recording medium and a second position where the information signal once recorded is prevented from being erased. The disk cartridge according to claim 1, which is a prevention member.