JPH081845Y2 - Mold for cassette case molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention mainly relates to a cassette case molding die for molding a case body of a video cassette case.

"Prior Art" In general, a video cassette case in which a video tape is housed has a structure in which a pair of upper and lower case bodies are combined. In recent years, as product designs have diversified, and in particular, as the design of the upper surface of the upper case body has diversified, it is necessary to newly manufacture a cavity mold for forming the upper surface of the upper case body in order to cope with this. Is occurring.

"Problems to be solved by the invention" However, when a cavity mold is newly manufactured and replaced in this way, it takes time to manufacture because the cavity mold is complicated and the amount of processing is large. There is the problem of high costs.

Therefore, in order to solve the above problem, the following cassette case molding die is provided.

That is, as shown in FIGS. 3 and 4, the cavity mold 2 forming the outer surface 1a of the upper case body 1, the cavity mold 2 forming the design surface 1c of the upper surface 1b of the upper case body 1, The insert mold 3 is composed of a cavity mold body 4 which is detachably fitted to form an upper surface outer edge portion 1d and a side face 1e of the upper case body 1. By replacing the insert mold 3, the design surface can be improved.
It corresponds to the change of 1c.

Therefore, in the cassette case molding die having the above-described configuration, the design surface 1c can be changed only by processing the insert die 3, so that the manufacturing cost can be reduced.

However, in the above-mentioned cassette case molding die, since the insert die 3 is fitted to the cavity die main body 4 in a state of being lapped, it takes a lot of time to process the insert die 3, and as a result, the design surface 1c is changed. However, there is a problem in that burrs are easily generated in this portion due to the clearance K between the insert die 3 and the cavity body 4.

"Purpose of Invention" This invention was made in view of the above circumstances,
An object of the present invention is to provide a mold for molding a cassette case, which can easily change the design surface of the case body and can prevent burrs from being generated during molding.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention is a molding die for molding a case body of a cassette case in which side plates are vertically provided on the outer periphery of a bottom plate. A core mold for molding the inner surface side of the case body that is brought into contact with and separated from the case body, and a cavity mold for molding the outer surface side of the case body, wherein the cavity mold is a curved surface of the outer surface of the bottom plate and the intersecting ridge of the bottom plate and the side plate. It comprises a first cavity mold for molding the outer surface of the part and a second cavity mold for molding the outer surface of the side plate, and these first and second cavity molds are brought into close contact with each other with a flat contact surface. In this state, a mold for forming a cassette case is proposed, which is integrally fixed in a fixed state by a detachable fastener.

[Operation] With the cassette case molding die according to the present invention, the first cavity mold for molding the outer surface of the bottom plate of the case body and the curved surface of the intersecting ridge between the bottom plate and the side plate is integrally formed. Therefore, there is no mold parting line such as an insert mold in the part that molds the outer surface of the bottom plate of the case body of the cassette case,
No burr is generated on the outer surface of the bottom plate of the case body during injection molding.

Also, the cavity mold can be divided into a first cavity mold and a second cavity mold, but since they are brought into close contact with each other at the contact surface and are integrally fixed by a fastener, there is no clearance between them and injection molding is performed. It becomes possible to prevent the occurrence of burrs. Moreover, since the contact surface is formed in one plane, it can be easily processed.

Furthermore, by removing the fasteners that fix the first cavity mold and the second cavity mold, the two cavity molds can be separated, so that the first cavity mold can be easily replaced. And by this,
It is possible to easily change the design of the bottom plate of the case body.

[Embodiment] An embodiment of the cassette case molding die of the present invention will be described below with reference to FIGS. 1 and 2.

In these drawings, reference numeral 10 is the outer surface 1a of the upper case body 1.
3 shows a cavity mold for forming a. The cavity mold 10 has an upper surface 1b on which a design surface 1c of the upper case body 1 is formed, and a curved surface 11 at an intersecting ridge portion between the upper surface 1b and the side surface 1e of the upper case body 1.
The upper mold surface (first cavity mold) 12 and the side surface mold 13 (second cavity mold) that is closely adhered to the joining surface (adhesion surface) 12a of the upper surface mold 12 and forms the side surface 1e of the upper case body 1. Cavity type).

The upper surface mold 12 and the side surface mold 13 are flush with the edge portion of the curved surface 11 of the upper surface mold 12 and the edge portion of the inner side surface 13a of the side surface mold 13, and are fastened with a bolt (fastener) not shown. It is joined by.

When the upper case body 1 is injection-molded by using the cavity mold 10 configured as described above and the core mold that faces the cavity mold 10 and molds the inner surface of the upper case body 1, the core mold is formed as in the conventional case. A cavity (cavity) is formed between the core die and the cavity die 2 by bringing the movable die plate including the die into contact with the fixed die plate including the cavity die 10, and the molten resin is injected and supplied into the cavity. And the upper case body 1 is molded.

In this case, since the upper surface mold 12 forming the design surface 1c is not fitted in the cavity mold body 4 in a lapped state like the conventional nesting mold 3, the upper surface mold 12 and the side surface mold 12
There is no clearance between 13 and 13 so there is almost no burr during molding. Moreover, even if burrs occur between the joining surfaces of the upper surface mold 12 and the side surface mold 13, the design surface
Since it does not occur in 1c, it does not reduce the design effect, and furthermore, this burr is easy to remove and the removed mark is inconspicuous.

When it is necessary to change the design surface 1c of the upper edge 1b of the upper case body 1, only the top die 12 is newly manufactured, and the top die 12 is joined and fixed to the side die 13. Often,
It is possible to quickly and smoothly respond to changes in product design. In this case, since the upper surface mold 12 is not fitted with each other by lapping like the conventional insert mold 3, it is easy to process and can be manufactured at a lower cost.

Further, the upper surface mold 12 is provided with an upper surface 1b and a side surface 1e of the upper case body 1.
Since a surface for molding the curved surface 11 of the ridge portion is formed and the surface for molding the curved surface 11 is not divided by the parting line of the upper surface mold 12 and the side surface mold 13, the curved surface 11 of the upper case body 1 is formed. Can be formed into a smooth surface without burrs.

In the above embodiment, the upper surface 1b of the upper case body 1 whose design is often changed has been described, but in some cases, the lower surface of the lower case body paired with the upper case body 1 has the same upper surface (lower surface). ) The mold may be used to handle design changes.

"Effect of the Invention" As described above, the cassette case molding die according to the present invention is a molding die for molding a case body of a cassette case in which side plates are vertically provided on the outer periphery of a bottom plate. A core mold for molding the inner surface side of the case body and a cavity mold for molding the outer surface side of the case body, which are brought into contact with and separated from each other, and the cavity mold is a curved surface of the outer surface of the bottom plate of the case body and the intersecting ridge of the bottom plate and the side plate. The first cavity mold for molding the outer surface of the portion and the second cavity mold for molding the outer surface of the side plate are provided, and these first and second cavity molds are
Since they are integrally fixed by the detachable fasteners in a state where they are brought into close contact with each other on the flat contact surface, the following effects can be obtained.

First, since there is no mold parting line such as a nesting mold in the first cavity mold for molding the outer surface of the bottom plate of the case body of the cassette case and the curved portion of the intersecting ridge, burrs are formed on the outer surface of the bottom plate of the molded case body. It can be prevented from occurring. Therefore, the appearance quality of the cassette case can be improved.

Further, since the cavity mold is composed of the first and second cavity molds that can be divided, the design of the bottom plate outer surface of the cassette case can be easily changed by exchanging the first cavity mold. In this case, unlike the conventional nesting type, the two cavity types are not fitted together by rubbing, but the two cavity types are brought into close contact with each other by the contact surface which is one flat surface. The contact surface can be easily processed. Therefore, the manufacturing cost of the mold can be reduced, and by fixing both cavity molds integrally with the fastener, it is possible to eliminate the clearance on the contact surface and prevent the occurrence of burrs. Further, the two cavity molds can be easily fixed to the injection molding machine in a state where they are integrally formed.

[Brief description of drawings]

FIGS. 1 and 2 show an embodiment of a cassette case molding die of the present invention. FIG. 1 is a sectional view of a main part of the die, and FIG. 2 is a sectional view of a top die. FIG. 3 is a cross-sectional view of a main part of a conventional cassette case molding die, and FIG. 4 is a perspective view of an upper case body. 1 ... Upper case body, 1a ... Outer surface, 1b ... Top surface, 1c ... Design surface, 1e ... Side surface, 10 ... Cavity type, 11 ... Curved surface (ridge), 12 ... Top surface type, 13 ...... Side type.

Claims (1)

[Scope of utility model registration request] 1. A molding die for molding a case body of a cassette case in which a side plate is vertically provided on an outer periphery of a bottom plate, the core die for molding the inner surface side of the case body by contacting and separating from each other. And a cavity mold for molding the outer surface side, the cavity mold for molding the outer surface of the bottom plate and the outer surface of the curved portion of the intersecting ridge between the bottom plate and the side plate, and the cavity mold of the side plate. A second cavity mold for molding the outer surface, and the first and second cavity molds are integrally fixed by a detachable fastener in a state where they are brought into close contact with each other on a flat contact surface. A mold for molding a cassette case, which is characterized in that