JP2939952B2 - Mold unit for molding audio tape cassette half - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold apparatus for molding audio tape cassette halves, and more particularly to a mold apparatus capable of selectively molding a plurality of types of tape cassette halves having different head position discriminating holes. Molding device.

[0002]

2. Description of the Related Art An audio cassette tape is shown in FIG.
17 to 17, the magnetic tape 2 wound around a pair of rotatable hubs 1 is housed in a cassette 3. The cassette 3 has a pair of cassette halves 4a and 4b.
Are combined. These cassette halves 4a,
As shown in FIGS. 9 and 10, 4b has a thin case shape in which the side plates 6, 7, 8 are bent perpendicularly from the respective edges of the rectangular flat base surface 5. A transparent window 9 for seeing through the tape diameter is provided at the center of the substrate portion 5. At both ends of the rear side surface portion 8 of the cassette 3, claws 11 are formed on each of the cassette halves 4a and 4b to be bent when it is desired to prevent erroneous erasure of recording on the magnetic tape 2. By the way, there are a plurality of types of audio cassette tapes having different head positions, but in order to automatically determine the head position of the cassette tape mounted on the cassette tape player side,
The form of the head position determination holes 12 and 13 formed in the rear side surface portion 8 of the cassette 3 is changed according to the difference in the head position. That is, in the case of the cassette tape in the metal position, as shown in FIGS.
Are formed, and a pair of head position discriminating holes 13 is also formed in the center of the side surface portion 8. Also,
In the cassette tape at the chrome position, as shown in FIG. 16, head position discriminating holes 12 are respectively formed only at both end portions of the side surface portion 8 of the cassette 3. further,
The cassette tape in the normal position has no head position determination hole as shown in FIGS. The head position determination holes 12 and 13 are provided in the cassette 3
Although it opens to the outside, the head position determination hole 1
The ribs 14 and 15 that surround the head position discriminating holes 12 and 13 from inside the cassette 3 surround the cassette half 4 and surround the cassette half 4.
It is formed on the inner surfaces of a and 4b. The ribs 14 surrounding the head position determination holes 12 at both ends of the side surface portion 8 are
Is connected to the rib 16 surrounding the.

[0003] Incidentally, the tape cassette half 4a,
4b is a single piece of plastic, for example, Japanese
As described in JP-A-1-205778
By changing only the nest in the mold
Multiple types of tapes with different
Mold half using a common mold device.
Has been done in the past. Similarly, there is a mold apparatus which can selectively form a plurality of types of tape cassette halves 4a and 4b having different forms of the head position determination holes 12 and 13 as described above. That is, in this mold apparatus, formation or non-formation of the head position determination holes 12 and 13 can be selected by exchanging the insert. Here, a configuration that has conventionally been adopted to enable selection of formation or non-formation of the head position determination holes 12 and 13 will be described by taking one head position determination hole 13 as an example. 11 to 1
In FIG. 4, 21 is a cavity body member, 22 is a core body member, and these cavity body member 21 and core body member
Numeral 22 moves vertically in the figure to open and close, and forms a cavity 23 in the shape of the cassette halves 4a and 4b at the time of mold clamping. Note that the opening and closing directions of the cavity main body member 21 and the core main body member 22 are the cassette half 4a,
This is a direction orthogonal to the base surface 5 of 4b. Further, the cavity body member 21 forms the outer surfaces of the cassette halves 4a and 4b,
The core body member 22 forms the inner surface of the cassette halves 4a and 4b. At a position corresponding to the head position determination hole 13 in the core main body member 22, a concave nesting portion 24 is formed. This nesting part 24
The discriminating hole forming nest 25 and the discriminating hole non-forming nest 26 are detachably and selectively attached. The cavity body member 21 has a recess 27 into which a portion of the inserts 25 and 26 located outside the cavity 23 is fitted. And, the discriminating hole forming nest 25,
As shown in FIGS. 11 and 13, the cassette halves 4a,
It has a shape penetrating through the side surface portion 8 of 4b, and forms the head position determination hole 13 and the front surface side of both surfaces of the rib 15 surrounding the hole. In addition, a concave portion 28 that forms the back side of the rib 15 is formed in the core main body member 22. On the other hand, as shown in FIGS. 12 and 14, the discriminating hole non-forming nest 26 has a groove 29 for forming the side surface portion 8 for closing the head position discriminating hole 13, but also the surface of the rib 15. It also forms the side. That is, as shown in FIG. 10, the conventional mold apparatus does not have the corresponding ribs even when the head position determination holes 12 and 13 are not formed.
14 and 15.

[0004]

As described above, according to the conventional mold apparatus for molding the tape cassette halves 4a and 4b, even if the head position discriminating holes 12 and 13 are not formed, the corresponding ribs 14 and 15 are formed. Are formed, but these ribs 1
4 and 15 are when there are no head position discriminating holes 12 and 13.
Functionally unnecessary. That is, when the head position determination holes 12 and 13 are not formed, the ribs 14 and 15
Forming wastes unnecessary use of resin. When the ribs 14 and 15 are formed, the cassette half 4
There is also a problem that sink marks tend to occur at positions corresponding to the ribs 14 and 15 on the surfaces of a and 4b.

An object of the present invention is to solve such a problem, and a resin used in a mold apparatus capable of selectively molding a plurality of audio tape cassette halves having different forms of head position determination holes. While reducing the occurrence of sink marks due to the formation of the ribs.

[0006]

According to the present invention, there is provided a tape cassette half comprising a base portion and a side portion bent from an edge of the base portion. In a mold apparatus for molding an audio tape cassette half capable of selectively molding a plurality of types of tape cassette halves having different forms of head position determination holes to be opened and closed in a direction orthogonal to the base surface of the tape cassette half. A pair of mold members that form a tape cassette half-shaped cavity inside at the time of mold clamping, and a plurality of types of nests that are detachably and selectively attached to nest attachment portions provided on the mold members, As these nests, the head position determination hole of the tape cassette half and the head position determination hole are inserted into the tape cassette half. Said tape cassette C with a discriminating hole forming nested to form the front and back surfaces of ribs for blocking, in place of the head position determination holes to form the side portions
A discriminating hole non-forming nest for flattening a position corresponding to the rib on the inner surface of the roof.

[0007]

In the mold apparatus for molding an audio tape cassette half according to the present invention, a pair of mold members are clamped to form a tape cassette half-shaped cavity between the mold members, and a resin is formed in the cavity. To form a tape cassette half. At this time, when a head position determination hole is formed in the side surface of the tape cassette half, a determination hole forming nest is attached to the nest attachment portion of the mold member. The nesting for forming the discriminating hole forms a head position discriminating hole and both front and back surfaces of a rib for blocking the head position discriminating hole from inside the tape cassette half. On the other hand, when the head position discriminating hole is not formed, a discriminating hole non-forming nest is mounted on the nest mounting portion of the mold member. Due to the nest for forming no discrimination hole, a side portion is formed in the tape cassette half in place of the head position discrimination hole, and the tape
A position corresponding to the rib on the inner surface of the cassette half is formed flat.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the mold apparatus for molding an audio tape cassette half according to the present invention will be described below with reference to FIGS. 31 is a fixed mold, 32 is a movable mold, the fixed mold 31 has a cavity body member 33 which is a mold member forming an outer surface of the tape cassette half 4b,
The movable mold 32 has a core body member 34 which is a mold member forming the inner surface of the cassette half 4b. The fixed type
The movable mold 31 and the movable mold 32 are moved vertically in FIGS. 2 to 7 to open and close, and the cassette half 4b is closed when the mold is clamped.
Is formed between the cavity main body member 33 and the core main body member 34. The opening and closing directions of the fixed mold 31 and the movable mold 32 are orthogonal to the base surface 5 of the cassette half 4b. The cavity body member
In 33, a first primary runner 36 is formed on a parting line surface with the core body member 34, and the first primary runner 36 opens to a position to be the front side surface portion 6 of the cassette half 4b in the cavity 35. A gate 37 is formed at the tip of the first primary runner 36 as a submarine gate. Further, the cavity body member 33 of the core body member 34
The parting line with the second primary runner 38
Are formed. On the other hand, the cavity main body member 33 has a second primary gate 39 which communicates with the second primary runner 38 and opens to a position at the center of the rear side surface 8 of the cassette half 4b in the cavity 35 as a submarine gate. Is formed. Further, the core body member 34 includes:
A movable core member 40 forming the inner surface of the transparent window 9 of the cassette half 4b is slidably incorporated. On the other hand, in the cavity main body member 33, a secondary gate 41 composed of a direct gate facing the movable core member 40 is formed.

At a position corresponding to the head position discriminating holes 12 and 13 in the core body member 22, a pair of first nest mounting portions 46 and a pair of second nest mounting portions 46 are provided.
47 are formed in a concave shape straddling a position facing the cavity 35 and a position outside the cavity 35. The first nest mounting portion
46, a first discriminating hole forming nest 48 and a first discriminating hole non-forming nest 49 are removably and selectively mounted, and the second nest mounting portion 47 is The discriminating hole forming nest 50 and the first discriminating hole non-forming nest 51 are removably and selectively attached. That is, these nests 48, 49, 50, 51 are partially fitted into the nest mounting portions 46, 47 and are fixed to the core body member 34 by bolts 52 at positions outside the cavity 35. is there. The cavity body member
Recesses 53, 54 are formed in the nest 33 so that portions of the nests 48, 49, 50, 51 located outside the cavity 35 are fitted. Further, both the second nest mounting portions 47 and a pair of concave portions 54 corresponding to these, respectively, are provided with the second primary runner 38.
And the second primary gate 39.

The first discriminating hole forming nest 48 has a shape penetrating through the side face 8 of the cassette half 4b.
The head position determination hole 12 and the front and back surfaces of the rib 14 surrounding the hole are formed, and the claw 11 and the front surface side of the rib 16 surrounding the hole are formed. For this purpose, the first discriminating hole forming nest 48 is formed with a groove 56 serving as the rib 14 and a hole 57 serving as the claw 11, as shown in FIG.
In contrast, the first discriminating hole non-forming nest 49 is
Again, the claw 11 and the surface side of the rib 16 surrounding the claw 11 are formed, the side face 8 is formed instead of the head position determination hole 12, and the position corresponding to the rib 14 is formed flat. Further, a rib 17 having a shape in which the rib 16 is extended to the side surface portion 8 is formed. For this purpose, the first discriminating hole non-forming nest 49 is formed with a hole 57 serving as the claw 11 as shown in FIG.
A groove 58 serving as the side surface portion 8 in place of the head position determination hole 12 and a groove 59 communicating with the groove 58 and serving as the rib 17 are formed. The pair of claws 11 in the entire cassette 3 are formed separately in the two cassette halves 4a and 4b. Therefore, the first nests 48 and 49 at one end of the cassette half 4b have holes 57 serving as the claws 11 therein. However, the first nests 48 and 49 on the other end side
There is no hole 57. Further, the second discriminating hole forming nest 50
As shown in FIG. 4 and FIG. 6, the hole penetrates the side surface portion 8 of the cassette half 4b, and forms the head position discriminating hole 13 and the front and back surfaces of the rib 15 surrounding the hole. For this purpose, a groove 61 serving as the rib 15 is formed in the second discriminating hole forming nest 50. On the other hand, as shown in FIG. 5 and FIG. 7, the second discrimination hole non-forming nest 51 forms a side face portion 8 instead of the head position discrimination hole 13 and a position corresponding to the rib 15 is flat. It is formed in. For this purpose, the second discriminating hole non-forming nest 51 is formed with a groove 62 serving as the side surface portion 8 instead of the head position discriminating hole 13.

Next, the operation of the above configuration will be described. At the time of forming the tape cassette half 4b, the fixed mold 31 and the movable mold 32 are clamped and the movable core member 40 is fixed.
Is abutted against the cavity body member 33 to form a cassette half-shaped primary cavity 35 excluding the transparent window 9 between the cavity body member 33 and the core body member 34, and a primary runner 36 is formed in the primary cavity 35. , 38 are filled with opaque resin through primary gates 37, 39. Next, after the opaque resin is solidified, the movable core member 40 is separated from the cavity body member 33 to form a secondary cavity therein, and the secondary cavity is filled with a transparent resin from the secondary gate 41. Furthermore, after this transparent resin has solidified,
The fixed mold 31 and the movable mold 32 are opened, and the molded cassette half 4b is taken out.

By the way, the molding is performed by a head position discriminating hole.
When switching to the tape cassette half 4b having a different form of 12 and 13, the nests 48, 49, 50 and 51 are appropriately replaced.
That is, when the head position determining hole 12 is formed in the side surface portion 8 of the cassette half 4b, the first determining hole forming nest 48 is attached to the first nest mounting portion 46 of the core body member 34, and the head position determining hole 12 is formed. Is not formed, the first discriminating hole non-forming nest 49 is attached. Also,
When the head position determination hole 13 is formed, the second determination hole forming nest 50 is attached to the second nest mounting portion 47 of the core body member 34, and when the head position determination hole 13 is not formed, the first determination hole is formed. The non-forming nest 51 is attached. That is, when forming the cassette half 4b having the same metal position as that shown in FIG. 9, the first discriminating hole forming nest 48 and the second discriminating hole forming nest 50 are attached. When forming the tape cassette half 4b in the chrome position, the first discriminating hole forming nest 48 and the second discriminating hole non-forming nest 51 are attached.
Furthermore, when molding the tape cassette half 4b of the normal position as shown in FIG. 8, attaching the first discriminating hole non-forming nesting 49 and the second discriminating hole non-forming nested 51. When the first discriminating hole forming nest 48 is attached, the first discriminating hole forming nest 48 forms the head position discriminating hole 12 and both the front and back surfaces of the rib 14 surrounding the hole, and the claw. 11 and ribs surrounding it
16 are formed. The back surface of the rib 16 is formed by the core body member 34. On the other hand, when the first discriminating hole non-forming nest 49 is attached, the side face portion 8 is formed by the first discriminating hole non-forming nest 49 instead of forming the head position discriminating hole 12. Also, rib 14
Are not formed, and a position corresponding to the rib 14 is formed flat. At the same time, the claw 11 and the ribs 16 and 17 surrounding the claw 11 are formed. When the second discriminating hole forming nest 50 is attached, the first discriminating hole forming nest 50 forms the head position discriminating hole 13 and both the front and back surfaces of the rib 15 surrounding it. On the other hand, when the second discrimination hole non-forming nest 51 is attached, the head position discrimination hole 13
Is not formed, instead of forming the second discriminating hole
51 forms the side surface portion 8. With this, the rib
15 is not formed and the tape cassette half 4b is
Position is flatly formed corresponding to that rib 15.

As described above, according to the configuration of the above embodiment, the nests 48, 49, 50, 51 for selecting formation or non-formation of the head position discriminating holes 12, 13 are provided at the entire positions of the ribs 14, 15. When the head position determination holes 12 and 13 are not formed, the ribs 14 and
Since 15 is not formed, the amount of resin used for molding the tape cassette half 4a can be saved. When the head position determination holes 12 and 13 are not formed, sink marks do not occur on the outer surface of the tape cassette half 4a at positions corresponding to the ribs 14 and 15. Thus, the occurrence of sink marks due to the formation of the ribs 14 and 15 can be reduced as much as possible.

The configuration and operation of the mold device for molding one of the tape cassette halves 4a and 4b constituting the cassette 3 have been described above.
The same applies to the configuration and operation of the molding die apparatus for the other cassette half 4a. FIG. 8 shows the other tape cassette half 4a formed by the mold apparatus of the present embodiment.

The present invention is not limited to the above-described embodiment, and various modifications can be made. For example,
In the above embodiment, the discriminating hole forming nests 48 and 50 are formed on both the front and back surfaces of the ribs 14 and 15 surrounding the head position discriminating holes 12 and 13. Even if only the ribs are formed, the discrimination hole non-forming nest can be formed without ribs by abutting the core body member at a position corresponding to the ribs.

[0016]

According to the present invention, by exchanging the nest,
In a mold device capable of selectively molding a plurality of types of audio tape cassette halves having different forms of head position determination holes on the side surface, the head position determination holes and the head position determination holes are nested as tape cassette halves. A nest for forming a discrimination hole that forms both front and back surfaces of a rib that is cut off from the inside, and a side portion of a tape cassette half formed instead of a head position discrimination hole, and a position corresponding to the rib on the inner surface of the tape cassette half is flattened. When the head position discrimination hole is not formed, the rib surrounding the head position discrimination hole is not formed, so that the amount of resin used for molding the tape cassette half can be saved. The generation of sink marks due to the formation of ribs can be reduced as much as possible.

[Brief description of the drawings]

FIGS. 1A and 1B show an embodiment of a mold apparatus for molding a tape cassette half according to the present invention, wherein FIG. 1A is a plan view of a core body member, and FIG. 1B is a plan view of a cavity body member.

FIG. 2 is a perspective view of the vicinity of a first discriminating hole forming nest attached to the core body member.

FIG. 3 is a perspective view showing the vicinity of a first discriminating hole non-forming nest attached to the core body member;

FIG. 4 is a perspective view of the vicinity of a second discriminating hole forming nest attached to the core body member;

FIG. 5 is a perspective view of the vicinity of a second discriminating hole non-forming nest attached to the core body member;

FIG. 6 is a sectional view of the portion shown in FIG. 4;

FIG. 7 is a sectional view of the portion shown in FIG. 5;

FIG. 8 shows a normalizer formed by the mold apparatus of the embodiment.
It is a perspective view of the tape cassette half Le positions.

FIG. 9 is a perspective view of a tape cassette half in a metal position.

10 is a perspective view of the tape cassette half the normal port <br/> Jishon molded by conventional molding apparatus.

FIG. 11 is a perspective view showing an example of a conventional mold apparatus for molding a tape cassette half, in the vicinity of a discriminating hole forming nest attached to a core body member.

FIG. 12 is a perspective view of the vicinity of a discriminating hole non-forming nest attached to the core body member;

FIG. 13 is a sectional view of the portion shown in FIG. 11;

FIG. 14 is a sectional view of the portion shown in FIG. 12;

FIG. 15 is a perspective view of a cassette tape in a metal position.

FIG. 16 is a perspective view of the cassette tape in a chrome position.

FIG. 17 is a perspective view of a cassette tape in a normal position.

[Explanation of symbols]

4a, 4b Tape cassette half 5 Base face 6 Side face 7 Side face 8 Side face 12 Head position discriminating hole 13 Head position discriminating hole 14 Rib 15 Rib 33 Cavity main body member (Mold member) 34 Core main body member (Mold member) 35 Cavity 46 First nest mounting part (nest mounting part) 47 Second nest mounting part (nest mounting part) 48 First nesting hole for forming discriminating hole (nesting for forming discriminating hole) 49 No first discriminating hole formed Nest for Nesting (Non-Forming Discriminating Hole) 50 Nesting for Nesting of Discriminating Hole (Nesting for Forming Discriminating Hole) 51 Nest for Nesting for Non-Forming Discriminating Hole

Claims (1)

(57) [Claims] 1. A tape cassette half comprising a base surface portion and a side surface portion bent from an edge of the base surface portion, wherein a plurality of types of tape cassette halves having different forms of head position determination holes formed in the side surface portion. In a mold apparatus for molding an audio tape cassette half capable of selectively molding a pair of tape cassette half-shaped cavities which are opened and closed in a direction orthogonal to a base surface portion of the tape cassette half to form a tape cassette half-shaped cavity at the time of mold clamping. A mold member; and a plurality of kinds of nests which are detachably and selectively attached to nest attachment portions provided on the mold member. As these nests, a head position determination hole of the tape cassette half and the head are provided. Nesting for forming discrimination holes that form both front and back sides of ribs that block position discrimination holes from inside the tape cassette half Forming the side portion in place of the head position determination hole and the tape cassette housing.
A mold for molding an audio tape cassette half, comprising: a discriminating hole non-forming nest that flatly forms a position corresponding to the rib on the inner surface of the tape.