JP4433595B2 - Mold for casting - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a casting mold, and more particularly to a casting mold for a complicated structure.
[0002]
[Prior art]
When casting a complex structure that includes a notch (undercut), conventionally, after casting with a shape that leaves the part where the notch is formed, the notch is machined. It was common to form. However, when such a method is adopted, there is a disadvantage that the man-hour is increased and the cost is increased. In particular, it is desirable to reduce the number of man-hours after casting as much as possible for relatively small mass-produced products, because accuracy is required for machining. However, there has been no report of a mold corresponding to a casting having a notch.
[0003]
[Problems to be solved by the invention]
As described above, conventionally, there is no metal mold for casting a complicated structure including a notch, and casting is performed while leaving a portion to be a notch, and then the notch is machined. It is generally formed, and there is a drawback that the number of man-hours after the fact increases.
An object of the present invention is to solve this problem by a relatively simple method, and to realize a casting mold that can cast a casting including a notch and eliminate subsequent processing.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a protruding portion corresponding to the cutout portion and a flat portion corresponding to the other portion, and enables the protruding portion to be retracted inside the flat portion . And it is set as the casting metal mold | die for manufacturing the casting which has the notch part (undercut) which provided the wedge-shaped space which spreads from a surface position to the rear part between adjacent parts . Thereby , the metal mold | die which can manufacture the casting containing a notch part by one casting relatively easily is realizable.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a casting mold according to the present invention will be described in detail with reference to the accompanying drawings.
[0006]
FIG. 1 is an external perspective view of a portable CD player having a lid part to be cast by the casting mold of the present invention with the lid opened. In FIG. 1, reference numeral 1 is a main body, reference numeral 1-3 is a stopper, reference numeral 2 is a lid, reference numeral 2-1 is a locking mechanism, and reference numeral 2-2 is a hinge arm.
The main body 1 of the casing is formed by molding a mixed resin of PC (polycarbonate) and ABS resin, for example. Moreover, the cover part 2 is manufactured by die-casting of a magnesium alloy including the protrusions of the lock mechanism 2-1 and the hinge arm part 2-2.
[0007]
The hinge arm portion 2-2 of the lid portion 2 is inserted from the notch of the main body portion 1 and is supported inside the main body portion 1 at the center of rotation of the hinge portion. A coil spring is housed in the main body 1 and one end thereof is locked to the hinge arm 2-2. When the coil spring is extended, the coil spring pushes up the hinge arm portion 2-2, thereby opening the lid portion 2.
In closing, when the user pushes down the lid 2, the locking mechanism 2-1 of the lid 2 is bitten by the clasp 1-3 of the main body 1 and the lid 2 is held in a closed state. When the clasp 1-3 is opened from the closed state, the coil spring extends and the lid portion 2 opens smoothly.
[0008]
As shown in FIG. 2, the lock mechanism 2-1 has an undercut so as to bite the clasp 1-3 of the main body 1. Such an undercut is not formed directly by the conventional casting method, but after casting in a form that leaves a portion where the undercut should be formed, the undercut is formed by removing this portion by machining. It was.
[0009]
FIG. 3 shows a cross-sectional view of an embodiment of the mold of the present invention. In FIG. 3, reference numeral 3 denotes a protruding portion of the mold, and reference numerals 4-1, 4-2, and 4-3 denote planar portions. Reference numeral 5 denotes a wedge-shaped space provided between each part of the mold. The projecting portion 3 is configured to be movable in the direction of the arrow between the plane portions 4-1 and 4-2. When casting, the mold is cast in the form shown in the figure by extruding the protruding portion 3 from the flat portions 4-1 and 4-2, and when the casting is finished and the mold is removed, the protruding portion 3 is moved to the flat portion. 4-1 and 4-2 are pushed in and removed from the casting.
By doing so, a structure having a complicated shape having an undercut can be cast into a final shape without subsequent processing, and the number of work steps can be greatly reduced.
[0010]
By the way, in the die casting of a magnesium alloy, it was necessary to raise the temperature of hot water (melted alloy) to about 800 to 900 ° C. At such a high temperature, the mold thermally expands and the respective parts are pressed against each other, which may cause a problem that the mold cannot be removed even at a temperature after the casting is finished. In order to avoid this, a wedge-shaped space that extends from the surface position to the rear part is provided between the respective parts of the mold. Thereby, it becomes easy to remove the mold even at a relatively high temperature, and the work can be efficiently performed.
[0011]
In the embodiment of FIG. 3, the protruding portion 3 is escaped by being retracted between the flat portions 4 (4-1, 4-2), but depending on the positional relationship between the size of the protruding portion 3 and the flat portion 4. Since the operation of the flat portion 4 and the operation of the protruding portion 3 are interlocked, the protruding portion 3 can be released to the space formed by the retreat of the flat portion 4. Also in this case, it is effective to provide a wedge-shaped space between each part of the mold for efficient work.
[0012]
【The invention's effect】
As described above, the invention according to claim 1 of the present invention is a casting mold for producing a casting having a notch (undercut), and a projection corresponding to the notch, and the other parts. A planar portion corresponding to the portion, and the protruding portion can be retracted inside the planar portion.
As a result, it is possible to realize a mold capable of casting a complex-shaped structure having an undercut into a final shape without subsequent processing, and greatly reducing the work man-hours. it can.
[0013]
In addition , a wedge-shaped space extending from the surface position to the rear portion is provided between adjacent portions. Accordingly, it is possible to solve the problem that the mold is difficult to be removed due to thermal expansion, and it is possible to realize a mold that can be easily removed even at a relatively high temperature and can be operated efficiently.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a portable CD player having a lid part to be cast by a casting mold according to the present invention in a state where a lid is opened.
FIG. 2 is an explanatory diagram showing the shape of a lock mechanism of a lid of the portable CD player shown in FIG.
FIG. 3 is a cross-sectional view of an embodiment of a mold according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Main-body part, 1-3 ... Clasp, 2 ... Cover part, 2-1 ... Lock mechanism, 2-2 ... Hinge arm part, 3 ... Projection part, 4-1, 4-2, 4-3 ... Plane Part 5, 5 wedge-shaped space.

Claims (1)

A protrusion corresponding to the notch ,
A plane portion corresponding to the other portion,
Allowing the protruding portion to be retracted into the planar portion ;
In addition, a wedge-shaped space that extends from the surface position to the rear is provided between adjacent parts.
A casting mold for producing a casting having a notch (undercut) .

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