JPH11207789A - Method and apparatus for injection molding shell for recording and/or reproducing disk and its product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a product of a high quality level and high accuracy by forming an overall surface area as a smooth surface without forming a gate mark on a surface of an upper cell or a lower cell. SOLUTION: The apparatus for injection molding a shell for a recording and/or reproducing disk comprises a protrusion-like fixed mold 1 having a mechanism for injecting a molding resin in a melted state, a recess-like movable mold 2 to be brought into contact with or separated from the mold 1, and an auxiliary movable mold 8 for an edge. A cavity 7 of an upper cell and/or a lower cell of a shell for a recording disk is formed by these molds. Thus, a gate of the cavity 7 can be formed at the mold 4 of a position corresponding to a rear side of the cell. And, a removing mechanism for releasing and removing the molded cell adhered to the mold 2 at the time of opening the mold is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for injection-molding a shell for a high-quality recording and / or reproducing disk having high moldability, and an apparatus and a product thereof.

[0002]

2. Description of the Related Art Many types of shells for recording and / or reproducing disks of this kind are produced as casings for new media such as MD (mini-disc) and MO (magneto-optical) disks.

FIGS. 7 (a), 7 (b) and 7 (c) and FIG.
(A), (b), and (c) show a recording disk shell of this type of recording disk shell conventionally known. FIG. 7 shows a rectangular upper cell (I), and FIG. 8 shows a rectangular lower cell (II). (A) is a front view, (b) is a rear view, and (c) is a cross-sectional shape. The recording disk shell is formed by a combination of these two cells. A disc-shaped recordable and / or reproducible disc (not shown) is built in the inside, and a necessary label is mainly attached to the surface of the upper cell, so that the disc is commercially available.

In each figure, a is a rectangular shutter window formed on one side, b is a center hole formed in the center, c ₁ and c _2.
Is ₂ on each of the surfaces A ₁ and A ₂ of the cells (I) and (II).
The gate traces formed at locations, B ₁ and B _2, are the respective cells (I),
The back surface of (II), d ₁ and d ₂ are small high four-peripheral walls formed at four circumferential positions of each cell (I) and (II), and e ₁ and e ₂ are the back surface of each cell (I) and (II). The protrusion pin marks formed at a number of locations are shown.

[0005] These cells (I) and (II) are mass-produced with a desired synthetic resin by means of injection molding, and most of the gate portions of the cavities constituting these cells (I) and (II) are formed. Was provided on the side corresponding to the surfaces A ₁ and A ₂ of the cells (I) and (II).

[0006]

As described above, the gate portion of the injection molding means is formed of the cavity cells (I) and (II) capable of molding the cells (I) and (II). When the upper cell (I) and the lower cell (II) are formed at locations corresponding to the surfaces A ₁ and A ₂ of (I) and (II), the surface A
₁ and A ₂ remain as gate traces c ₁ or c ₂ and become a local so-called non-smooth surface. As a result, the entire surface of both cells (I) and (II) cannot be formed as a completely smooth surface, which lowers the commercial value and has many disadvantages such as limitations on the shape, size and design of the label formed on the surface. .

[0007] The following are listed below: (1) Breaking, dents, distortions, etc. occur due to the gate during sticking of the seal.

(2) In the case of a gate in the shutter slide area on the front surface, the function of the operation is obstructed by a remaining gate or the like.

(3) The texture is poor due to the presence of the gate on the surface.

[0010] (4) In particular, when providing the gate in a position where the gate mark c ₁ is formed weld lines product becomes unsightly appearing in the product center.

[0011] There are drawbacks such as a
₁ and e ₂ are the back surfaces B ₁ and B _{2 in} each of the cells (I) and (II).
However, there is also an inconvenience that a transparent product is viewed through, and the image of the product is deteriorated because of the large number and the large trace shape.

The present invention has been made by paying attention to the points described above, and has high quality, high precision and high commercial value by forming a smooth surface over the entire surface without forming a gate mark on the surface of the upper cell or the lower cell. An object of the present invention is to provide a novel recording and / or reproducing disk shell injection molding method and apparatus capable of molding a product, and a product thereof.

[0013]

The present invention has solved the above-mentioned problems by providing the following constitution.
These are listed below.

(1) An injection molding method for injecting a desired molten synthetic resin into cavities formed by a fixed mold and a movable mold to mold an upper cell and / or a lower cell constituting a recording disk shell. During the mold clamping process between the fixed mold and the movable mold, the molten resin is injected into the cavity through a gate provided at a location corresponding to the back side of the cell to solidify and form the molten resin, and the movable mold moves. Recording and / or recording, wherein one of the front or back surfaces of the molding cell adhered to either one of the molds during the mold opening step is released and removed by a removing means such as suction. Injection molding method for disk shell.

(2) An injection molding method for injecting a desired molten synthetic resin into a cavity formed by a fixed mold and a movable mold to mold an upper cell and / or a lower cell constituting a recording disk shell. During the mold clamping process between the fixed mold and the movable mold, the molten resin is injected into the cavity through a gate provided at a location corresponding to the back side of the cell to solidify and form the molten resin, and the movable mold moves. The molding cell adhering to either one of the molds during the mold opening process is removed by a removing means such as suctioning one surface of the front surface or the back surface, and an auxiliary removing means by a protruding pin provided in the mold. A recording and / or disk shell injection molding method characterized in that it can be removed by releasing the mold.

(3) A convex fixed mold provided with a mechanism capable of injecting a molding resin in a molten state, a concave movable mold capable of moving toward and away from the fixed mold, and an auxiliary movable mold for an edge. To form a cavity for the upper cell and / or lower cell of the recording disk shell, so that the gate of this cavity can be formed in a fixed mold at a location corresponding to the back side of the cell and adhere to the movable mold when the mold is opened. An injection molding device for a recording and / or disk shell, comprising a detachable mechanism capable of releasing a molded cell from a mold.

(4) A convex fixed mold having a mechanism capable of injecting a molding resin in a molten state, a concave movable mold capable of moving toward and away from the fixed mold, and an auxiliary movable mold for edge, and these molds are provided. To form a cavity for the upper cell and / or lower cell of the recording disk shell, so that the gate of this cavity can be formed in a fixed mold at a location corresponding to the back side of the cell and adhere to the movable mold when the mold is opened. A detachable mechanism that can release the molded cell
And a recording and / or disk shell injection molding apparatus, comprising an auxiliary ejection pin in a movable mold.

(5) The auxiliary movable type for an edge is capable of reciprocally opening and closing in the transverse direction crossing the axial reciprocating opening and closing movement of the movable type. 5.) An injection molding apparatus for a recording and / or disk shell according to any of the preceding claims.

(6) An upper cell and / or a lower cell obtained by forming a gate mark on the outer periphery of the disk accommodating portion by the injection molding apparatus according to the above (4) or (5). Characterized recording and / or disk shell.

[0020]

Embodiments of the present invention will be described below.

(First Embodiment) First, a first embodiment will be described with reference to FIGS.

In each of the drawings, reference numeral 1 denotes a fixed mold that constitutes an injection molding apparatus; 2 denotes a movable mold that can move toward and away from the fixed mold 1;
Denotes a molten resin flow path provided with a valve gate mechanism 4 provided in the fixed mold 1, and the fixed mold 1 and the movable mold 2 mainly communicate with each other via a gate 6 opened and closed by a valve rod 5 of the valve gate mechanism 4. It leads to the cavity 7 that is constructed. In addition, the valve gate mechanism 4 and the gate 6 are one in FIG.

The cavity 7 has a convex portion 1a of the fixed mold 1 which conforms to the back and front surfaces of the cell P such as a rectangular upper cell or lower cell of the recording and / or reproducing disk shell and the four peripheral walls. When,
It is formed by the concave portion 2a of the movable mold 2 and the auxiliary auxiliary movable mold 8 that can form the opening edge of the four peripheral walls.

In addition, since the auxiliary movable mold for edge 8 needs to form an opening edge of the four peripheral walls of each cell P, for example, four directions in the front-rear and left-right directions between the fixed mold 1 and the movable mold 2 The tip of each of the divided auxiliary auxiliary movable molds 8 is movable along the movable mold 2 so as to freely contact and separate from the protruding side surface of the convex portion 1 a of the fixed mold 1. They are arranged freely (only two are shown only in the left-right direction in the figure, and the front-back direction is omitted).

The edge assist movable die 8 is closed as shown in FIGS. 1 and 2 (a) at the time of mold clamping, but is opened at the time of mold opening as shown in FIGS. 2 (b) to 2 (d). , (B) to (c), the movable mold 2 is moved in the lateral opening direction X crossing the movable mold 2 in the axial reciprocating movement, and is opposite to the opening direction X when the mold is clamped. It is formed so as to be capable of reciprocating opening and closing movement so that it can move in the closing direction Y.

FIG. 1 shows an example of a configuration in which the auxiliary movable die for edge 8 can be automatically reciprocally opened and closed.

Reference numeral 9 denotes cam rods which are disposed obliquely outwardly at four positions in front, rear, left and right with the convex portion 1a of the fixed die 1 interposed therebetween. This cam rod 9 penetrates obliquely through the cam hole 10 of the divided auxiliary auxiliary movable die 8 and has a tip 9a.
Is engaged in a part of the escape hole 11 of the movable mold 2.

That is, when shifting from the mold-clamped state to the mold-opened state shown in FIG.
a is engaged in the escape hole 11, but since it is the escape hole 11, the mold can be easily opened and the movable mold 2
The auxiliary movable mold for edge 8 mounted on the movable body 2 moves in the X direction in the horizontal direction due to the inclination of the cam rod 9 and can be opened in conjunction with the opening operation of the movable mold 2. In the initial stage of the operation, since the auxiliary movable mold for edge 8 is still engaged with the opening edge of the cell P in which the edge is movable, the movable mold 2 of the concave part 2a is smaller than the movable mold 2 of the concave mold 2a. The cell P having a high holding force to maintain the adhesion state to the other side is given an action force for peeling off from the four-periphery opening edge, and the cell P has an extremely high adhesion force as shown in FIGS. 2B to 2C. There is an advantage that the mold can be opened by adhering to the convex portion 2a side of the weak movable mold 2.

Numeral 12 is a means for taking out a product cell P provided with, for example, a suction mechanism, which is provided with a suction cup 12a and a suction pipe 12b, and in a mold opening process, as shown in FIGS. 2 (c) and 2 (d). The concave portion 2a of the movable mold 2
It can be separated and taken out. The take-out means 12 can operate over a part of or the entire surface of the product cell P.

FIGS. 5 (a), 5 (b), 5 (c) and 6
(A), (b), and (c) show a front view, a back view, and a cross-sectional view of an upper cell and a lower cell of a molded recording disk shell, and show the back surface 13 _{1 of} each of the cells P ₁ and P _2. , 13 ₂ , the gate traces 14 ₁ , 14 ₂ only slightly remain on the rough surface, and the entire surface 15 ₁ , 15 ₂ is obtained as a smooth surface R. The gate traces 14 ₁ , 14 ₂ of both cells P ₁ , P ₂ are formed in inconspicuous locations on the outer periphery of the disk accommodating locations 18 ₁ , 18 ₂ as shown in FIG. , Gate trace 14
_1, 14 is also ₂ protrude solidified problem, there is an advantage that does not give trouble to the disk stored.

Similar to the conventional products shown in FIGS. 7 and 8, each of the cells P ₁ and P ₂ also has a rectangular shutter window a, a center hole b, and a small four-height peripheral wall d ₁ and d. _{Shows 2} .

Further, as shown in a chain line in FIG. 1 and in FIG. 3, a protruding pin 16 may be additionally provided on the movable mold 2 in the same manner as in the prior art, and can be used together with the extracting means 12. The locations ejector pin 16 acts in this case, as shown in FIG. 5 (a), for example at a location unobtrusive peripheral rest recess a ₁ of the shutter window a cell P ₁ may be provided above one location, thus , the surface 15 in the cell P ₁ in FIG. 5
_The protrusion pin traces 17 are formed without damaging the smooth surface R of _one .

With the above structure, as shown in FIGS. 1, 2 and 3, the molten resin injected into the cavity 7 by the injection molding means at the time of clamping the fixed mold 1 and the movable mold 2 is cooled and solidified. At the same time, as shown in FIG. 2, the movable mold 8 for the edge is also opened in the lateral direction X by the mold opening operation of the movable mold 2, and the molded product cell P is joined from the convex portion 1a of the fixed mold 1 having a strong joining force. It can be in a state of being joined to the concave portion 2a side of the movable mold 2 having a weak force.

Next, the removal means 12 such as a suction cup 12a
Works, the molding cell P adhering to the concave portion 2a of the movable mold 2 can be very easily taken out by suction-release.

After the cell P is taken out as a product, the movable mold 2 returns to the fixed mold 1 again, enters the mold clamping state of FIG. 1, and the same operation can be repeated and continued.

The injection molding means is exemplified by the case where the valve gate mechanism 4 is used, but any other molding means may be used as long as it is a runnerless injection molding method capable of high precision molding, including other spear system methods. . Further, if necessary, a sprue method can be similarly implemented.

The above description is based on the case where only the extraction means 12 is used when the molding cell P is exclusively adhered to the concave portion 2a side of the movable mold 2 and the case where the extraction means 12 and the protruding pin 16 are used together. As described in the example, also in the case where the molding cell P is attached to the convex portion 1a of the fixed mold 1 and the mold is opened as shown in FIG.
The present invention can be implemented even when the protrusion pins 16 are used alone or in combination.

In this case, since the tip of the protruding pin 16 hits the rear surface of the molding cell P and does not act on the front surface, there is no problem that a special arrangement location must be specified. When used in combination with the take-out means 12, the force can be dispersed, so that the number of the protruding pins 16 can be reduced.

Furthermore, in these embodiments, the means for forming each cell constituting the shell for the recording disk has been exclusively described. However, other shells for the reproducing disk and the shell for the recording / reproducing disk, such as MD and MO disk casings. It can be widely used for cell molding.

[0040]

According to the present invention, recording and / or reproducing corresponding to the casing of an MD (mini-disc) or MO (magneto-magnetic) disk, which is expected to be a new medium which is expected to be a small and compact medium whose demand has been rapidly increasing recently. The upper cell or lower cell of the disk shell can be molded with high precision, especially since the gate location is set on the back of each cell, no gate marks can be formed on the surface, so it can be molded as a beautiful smooth surface, as shown below It has many effects like this.

(1) The surface design can be freely performed without concern for the gate position.

(2) The print design can be freely set without regard to the gate position.

(3) Breakage, dents, distortion, etc. due to gate marks during sticking of the seal can be prevented.

(4) A product can be produced according to the image without worrying about the trace of the protruding pin in the transparent product cell.

(5) In the die structure, a part or the whole of the product cell uses a holding mold opening of a detaching mechanism such as a suction cup suction means, and thereafter, the holding pin is released to eliminate the projecting pin. . In addition, even if a protruding pin is required, it can be set at an inconspicuous location with several extremely small pins.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a molding apparatus according to the present invention.

FIGS. 2A and 2B are cross-sectional explanatory views showing a molding method based on the molding apparatus of FIG. 1, wherein FIG.
Is an explanatory diagram showing the process of removing the molded product when the mold is opened in a state of change with time.

3A and 3B are cross-sectional explanatory views showing a molding method when a protruding pin is used in combination with the molding apparatus of FIG. 1, wherein FIG.
(B), (c) and (d) are explanatory diagrams showing a process of removing a molded product in a time-varying state when the mold is opened.

FIG. 4 is a cross-sectional explanatory view showing a molding method of a molding apparatus according to another embodiment of the present invention, where (a) shows a state at the time of mold clamping;
(B), (c) and (d) are explanatory diagrams showing a process of removing a molded product in a time-varying state when the mold is opened.

FIG. 5 shows a molded article upper cell molded by the apparatus and the method according to the present invention, wherein (a) is a surface view,
(B) is a rear view, and (c) is an explanatory sectional view.

FIG. 6 shows a lower cell of a molded article formed by the apparatus and the method according to the present invention, wherein (a) is a surface view and (b) is a surface view.
Is a rear view, and (c) is a cross-sectional explanatory view.

FIG. 7 shows a conventional upper cell, in which (a) is a mold clamping time, (b), (c) and (d) are mold opening times, and an explanatory diagram showing a process of taking out a molded product with a lapse of time.

FIG. 8 shows a lower cell of a conventional product, in which (a) shows a state when the mold is clamped, (b), (c) and (d) shows a state when the mold is opened, and a process of removing a molded product in a time-dependent manner.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Fixed mold 1a constituting injection molding 2a convex part 2 movable mold 2a concave part 3 molten resin flow path provided with valve gate mechanism 6 gate 7 cavity 8 auxiliary movable mold for edge 9 cam rod 10 cam hole 11 escape hole 12 extraction means 14 _1, 14 ₂ upper cell P ₁ is a product according to the present invention, Roaseru backside ₁₃ 1 _{P 2,} 13 gate mark 15 ₁ formed on _2, 15 ₂ upper cell P is a product according to the present invention _1, Roaseru surface 16 projecting pin 17 projecting pin marks 18 ₁ P _2, 18 ₂ disk receiving position a shutter window b center hole c _1, c ₂ each conventional cell (I), the surface a ₁ of the (II),
Gate mark A ₁ are respectively formed at two locations in A _2, A ₂ each cell of a conventional product (I), the surface B _1, B ₂ each cell of conventional product (II) (I), the rear surface d of (II) ₁ , d ₂ Small, four high four peripheral walls e ₁ , e ₂ Protruding pin marks of conventional cells (I) and (II)

Claims (6)

[Claims] 1. An injection molding method for injecting a desired molten synthetic resin into cavities formed by a fixed mold and a movable mold to mold an upper cell and / or a lower cell constituting a recording disk shell, During the mold clamping step between the fixed mold and the movable mold, the molten resin was injected into the cavity through a gate provided at a location corresponding to the back side of the cell to solidify and form the molten resin, and the movable mold moved. A recording and / or disc characterized in that one of the front surface or the back surface of a molding cell adhered to one of the molds during the mold opening step can be removed by releasing the mold using a removing means such as suction. Injection molding method for shell. 2. An injection molding method for injecting a desired molten synthetic resin into a cavity formed by a fixed mold and a movable mold to mold an upper cell and / or a lower cell constituting a recording disk shell, During the mold clamping step between the fixed mold and the movable mold, the molten resin was injected into the cavity through a gate provided at a location corresponding to the back side of the cell to solidify and form the molten resin, and the movable mold moved. During the mold opening process, the molding cell adhering to either one of the molds is separated by a detaching means such as suction on one of the front and rear surfaces thereof and an auxiliary detaching means using a protruding pin provided in the mold. An injection molding method for a recording and / or disk shell, characterized in that it can be removed by molding. 3. A convex fixed mold having a mechanism capable of injecting a molding resin in a molten state, a concave movable mold capable of moving toward and away from the fixed mold, and an auxiliary movable mold for an edge. A cavity for the upper cell and / or lower cell of the recording disk shell is formed, so that the gate of this cavity can be formed in a fixed mold corresponding to the back side of the cell and adheres to the movable mold when the mold is opened. An injection molding apparatus for a recording and / or disk shell, comprising a detaching mechanism capable of releasing a molded cell from a mold. 4. A convex fixed mold having a mechanism capable of injecting a molding resin in a molten state, a concave movable mold capable of moving toward and away from the fixed mold, and an auxiliary movable mold for an edge. A cavity for the upper cell and / or lower cell of the recording disk shell is formed, so that the gate of this cavity can be formed in a fixed mold corresponding to the back side of the cell and adheres to the movable mold when the mold is opened. An injection molding apparatus for a recording and / or disk shell, comprising: a removal mechanism capable of releasing a molded cell from a mold; and an auxiliary ejection pin in a movable mold. 5. The end movable auxiliary movable type is capable of reciprocatingly opening and closing in a lateral direction crossing the movable reciprocating axial reciprocating opening and closing movement. Recording and / or disk shell injection molding equipment. 6. A recording device comprising an upper cell and / or a lower cell, wherein a gate mark is formed outside the outer periphery of a disk accommodating portion by the injection molding apparatus according to claim 4. And / or disk shell.