JPS6251410A - Molding of multi-color article and mold thereof - Google Patents

Abstract

PURPOSE:To simplify the molding of a multi-color article by a method wherein a grooved gap to connect close molding parts with each other is formed so as to pour resin with different colors through the grooved gap in the respective close molding parts when the molding of resin part surrounding the close molding part is intended. CONSTITUTION:Firstly, a stationary mold 9 and a movable mold 8, by both of which a molding part 3 containing character parts 2 and 2' is molded, are opposite to each other so as to be contacted with each other under pressure. At this time, the tip part of a flat plate 13 abuts against the respective protruded parts 14 and 14' for constituting a plurality of enclosed molding parts 5 and 5' of the stationary mold 9. Under the above-mentioned state, resin for molding character is poured through a resin leading-in passage 15 and a gate 16 in order to mold the molding part 3 containing the character parts 2 and 2'. Secondly, the flat plate 13 is retreated so as to develop a grooved gap 17 and at the same time the movable mold 8 is transferred from the stationary mold 9 to a stationary mold 10 without releasing the molding part 3 from the movable mold 8 so as to oppose the mold 9 to the mold 10 in order to be brought into contact with each other under pressure and, after that, to pour resin for molding part with color different from that of the molding part 3 through a resin leading-in passage 18 and a gate 19 in order to mold a molding part 4 integrally with the molding part 3. Thus, a multi-color article with a large number of enclosed molding parts can be easily molded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for molding multicolored resin articles such as typewriter keys, and a mold for the molding.

[Conventional technology]

In a multicolored resin article, such as a typewriter key or similar article, as shown in FIGS. 12 and 13, a first molded part 3 having a character portion 2.2' forming the characters of the typewriter key 1; The second molding part 4 that forms the base is made of resin of a different color and is molded integrally. Therefore, the common movable mold and the fixed mold for the tjS1 molding part
Only the molded part 3 is molded, then the fixed mold is replaced without removing the first molded part 3 molded from the movable mold, and a resin of a different color is injected to form the second molded part n4 with the first molded part 3. A molding method of integrally molding is used. At this time, depending on the character to be formed, there may be a closed molded part 5.5' surrounded by the character part 2.2'. This closed molded part 5.5', also called island part, cannot be filled with the resin for the second molded part unless special resin channels are provided.

Therefore, in the conventional method, when molding the first molded part 3, r! Character portion 2 surrounding IMI molded portion 5.5'.
A pin is inserted from the movable mold directly under the character part 2.2', and a small hole 6.
6' is formed in the first molded part 3, and the small hole 6.
6' was used as a resin passage communicating the closed molded part 5.5' and the open part 7.

However, in this method, it is necessary to set a pin and drill a small hole 6.6' for each closing molded part 5.5'.
A typewriter key with a large number of closed molded parts 5.5' requires a large number of pins, which complicates the structure of the movable type and makes processing and assembly very troublesome. .

Furthermore, when molding typewriter keys that have the same shape but simply have different spellings of characters, there is a problem in that the movable molds must be replaced because the pin positions differ depending on the character.

[Problem that the invention seeks to solve]

The present invention was made in order to solve the above problems, and it is possible to easily mold a multicolored resin article having a large number of closed molded parts, and to easily mold a multicolored resin article having a plurality of closed molded parts. The object of the present invention is to provide a molding method and a molding die that can mold resin articles without replacing the movable mold.

[Means for solving problems]

Therefore, in the present invention, a movable mold having a molding part and a plurality of fixed molds facing the molding part of the movable mold and forming spaces for respective molding parts corresponding to the color of the resin are used to mold the surrounding area. In a method for molding a multicolor article, in which a multicolor resin article having a plurality of closed molded parts surrounded by resins of different colors is integrally molded, fj including a resin part surrounding the closed molded part
When molding the %1 molded part, a continuous groove-shaped void is formed so as to connect the plurality of closed molded parts, and then,
When molding the second molding part containing the plurality of rIi chain molding parts with a resin of a different color from the first molding part, each ff! A method for molding a multicolored article is provided, which comprises molding by injecting a chain-forming molding resin.

Further, in the present invention, as a mold suitable for carrying out the above method, a multicolored resin article having a plurality of rW chain molding parts surrounded by resins of different colors, a movable mold having a molding part, In a multi-color molding mold that integrally molds a molding part of the movable mold and a plurality of fixed molds facing each other and forming spaces for respective molding parts corresponding to the color of the resin, the movable mold is is provided with a groove connecting locations corresponding to the plurality of closed molding parts, a movable small piece is slidably attached to the bottom frame in the groove, and the movable small piece protrudes into and faces the molding part space. A nine-color mold is provided, which is capable of reciprocating from a position in contact with a fixed mold to a position recessed near the surface of a molding part of a movable mold.

〔Example〕

Embodiments of the present invention will be specifically described with reference to the drawings.

Figure m1 and Figure 2 are cross-sectional views of the mold for manufacturing typewriter keys, Figure 3 is a plan view of the movable mold, Figures 4 and 5 are plan views of the first and second fixed molds, respectively. Figure 6 is #S
It is a Kasuri perspective view of 1 molding part.

In this embodiment, a movable mold 8 and two fixed molds 9.10, which are compressed and moved by a ram, are used to form a plurality of closed molding parts 5.5' surrounded by character parts 2.2" as shown in FIG. ff112. The molding part 11 of the movable mold 8 is provided with a groove 12 passing through the movable mold 8 at a location corresponding to the closing molded part 5.5', and a flat plate 13 is formed in the groove 12. is slidably inserted.V plate 13
is urged by a spring (not shown) in the direction of protruding from the movable mold 8, and in a free state, its tip occupies a position protruding from the surface of the molding part 11 of the movable mold 8. Also,
A mechanism not shown allows the flat plate 13 to be moved backward against the spring pressure and fixed so that its tip is positioned near the surface of the molded part 11. The plate 13 constitutes a movable piece for forming a groove-like cavity connecting a plurality of closed molding parts 5.5'.

First, as shown in FIG. 1, a first stationary mold 9 and a movable mold 8 for molding the first molded part 3 including the character portions 2.2' are pressed against each other. At this time, the flat plate 13 is left in a free state. The flat plate 13 projects into the space for the first molding part by a spring (not shown), and its tip abuts on each of the protrusions 14.14' for forming the plurality of closed molding parts 5.5' of the first stationary mold 9. . In this state, 01 resin (for example, black) for character part molding is injected into the space for the first molding part through the resin introduction path 15 and the date 16, and the first molding part 3 including the character part 2.2'' is molded. .Here, since the part occupied by the flat plate 13 protruding into the space for the mi molding part is not filled with black resin, the molded first molding part 3 has a plurality of molded parts as shown in FIG. A groove-like cavity 1FiX17 connecting the closed molding parts 5.5' is formed on the back side of the character part 2.2'.

Next, as shown in FIG.
Without removing the movable mold 8 from the movable mold 8, the movable mold 8 is moved from the first fixed mold 9 to the second fixed mold 10, and the second fixed mold 1o and the movable mold 8 are brought into pressure contact with each other by facing each other. And plS1
A resin for the second molding part having a different color from that of the molding part 3 (for example, white) is injected into the space for the second molding part through the resin introduction path 18 and the date 19, and the second molding part 4, which has a white background, is colored black. It is molded integrally with the mi molding part 3 which forms the letters . Here, since the flat plate 13 has retreated to the vicinity of the surface of the molding part 11 of the movable mold 8, the groove-shaped void 17 formed on the back side of the character part 2.2' has a plurality of closed molding parts 5.5. ' and the open portion 7 form a continuous resin passage. Therefore,
A plurality of closed molded parts surrounded by character parts 2.2' 5.
5' can be reliably filled with white resin.

In the embodiments described above, in order to explain the operation simply, the typewriter key 1 which does not have two closing molded parts has been described as an example. However, the effects of the present invention become more apparent when a multicolored resin article having a large number of closed molded parts is molded.

For example, the first fixed mold 21 shown in FIG. 7 or 8.
Typewriter keys molded using 22 have many characters and many closed molded parts. However, according to the present invention, as shown in FIG.
．． By providing only one flat plate 13 in the movable mold 23 used opposite to the mold 22, all the I%HJIt-shaped parts can be filled with resin. Furthermore, the same movable mold 23 can be used for the fixed mold 21 shown in FIG. 7 and the fixed mold 22 shown in FIG. can.

To overcome this, the conventional method uses a fixed type 21 shown in Figure #7.
The movable mold 24 shown in FIG. 10 is attached to #! The fixed mold 22 shown in Fig. 18 has a movable mold 25 shown in Fig. 11, and a different movable mold dedicated to the red fixed mold has a large number of pins 26 at locations corresponding to the respective closed molding parts. I had to use it.

〔Effect of the invention〕

As explained above, according to the method of the present invention, a continuous groove-like void connecting a plurality of closed molded parts is formed when molding the first molded part. This has the effect of allowing the article to be shaped into a shape. Furthermore, according to the mold of the present invention, a groove-like void that becomes a resin passage to a plurality of closed molded parts is formed by the - pieces of movable pieces, so a multicolored article having a large number of closed molded parts is formed. However, it is possible to form resin passages to all closed molded parts with one or a few movable pieces, simplifying the structure of the mold, and simply changing the position and number of closed molded parts. An excellent effect is that multi-colored articles that differ only slightly can be molded using the same movable mold.

[Brief explanation of drawings]

1 to 6 show the first embodiment, and! @ Figures 1 and 2 are cross-sectional views of the mold, Figure 3 is a plan view of the movable mold, and Figure 4 is a cross-sectional view of the mold.
The figure is a plan view of the first fixed mold, FIG. 5 is a plan view of the fixed mold of tjS2, FIG. 6 is a perspective view of the first molding part, and FIGS. 7 to 9 are views of the second embodiment. 7 and 8 are plan views of the first fixed type, FIG. 9 is a plan view of the movable type, and FIGS. 10 and 11 are plan views of the conventional movable type.
2 is a perspective view of the typewriter key, FIG. 13 is a sectional view taken along the line X-X in FIG. 12, and FIG. 14 is a perspective view of the first molded part formed by the conventional method. 2.2'...Character part, 3...First molded part, 4...
・Second molded part, 5.5'...Closed molded part, 8...
Movable type. 9...First fixed mold, 10...Second fixed mold, 12
...Groove, 13...Flat plate (movable small piece), 17...Groove-shaped gap, 26...Pin. Agent Patent Attorney Mano Goto Figure 1 Figure 2 Figure 3 Figure 4 Figure 50 Figure 6 Figure 7 Figure 9 Figure 10 Figure 11

Claims (1)

[Claims] 1. Using a movable mold having a molding part and a plurality of fixed molds facing the molding part of the movable mold and forming spaces for each molding part corresponding to the color of the resin, A method for molding a multicolored article that integrally molds a multicolored resin article having a plurality of closed molded parts surrounded by resins of different colors, comprising: molding a first molded part including a resin part surrounding the closed molded part; When doing so, a continuous groove-shaped void is formed to connect the plurality of closed molded parts, and then a second molded part including the plurality of closed molded parts is molded with a resin different in color from the first molded part. A method for molding a multicolored article, characterized in that when molding, resin is injected into each closed molding part through the groove-like gap. 2. The molding method includes: forming a space for a first molding part formed by opposing a first fixed mold for molding a first molding part including a resin part surrounding the closed molding part and the movable mold; One movable piece is made to protrude from the movable mold, and with the movable piece in contact with each of the protrusions of the plurality of closed molded parts of the first fixed mold, resin is injected and the first movable piece is injected. a first molding step of molding one molded part; a movable piece retreating step of retracting the movable small piece to create a continuous groove-like gap; and then taking out the first molded part from the movable mold. the first stationary mold is replaced with a second stationary mold for molding a second molding section including the plurality of closed molding parts;
A resin different in color from the first molding part is injected into a space for the second molding part formed by facing the fixed mold and the movable mold to which the first molding part is attached, and forming the second molding part. A method for molding a multicolored article according to claim 1, further comprising a second molding step of molding. 3. A multicolored resin article having a plurality of closed molded parts surrounded by resins of different colors is combined with a movable mold having a molded part,
A multicolor mold for integrally molding using a molding part of the movable mold and a plurality of fixed molds facing each other and forming spaces for respective molding parts corresponding to the color of the resin, wherein the movable mold is is provided with a groove connecting locations corresponding to the plurality of closed molded parts, a movable small piece is slidably inserted into the groove, and the movable small piece protrudes into the molded part space and faces the molded part space. A multicolor molding die characterized in that it is capable of reciprocating movement from a position in contact with a fixed mold to a position retracted near the surface of a molding part of a movable mold. 4. The multicolor mold according to claim 3, wherein the movable piece is a single flat plate.