JPH0919943A - Multiple injection molding method and multiple injection mold - Google Patents

Abstract

(57) [Summary] (Correction) [PROBLEMS] To provide a multiple injection molding method having a short molding cycle, high productivity, and a small molding defect rate. SOLUTION: A stationary mold 1, a movable mold 30, and a slide mold 10 are used, and the slide mold 10 and the previous semi-molded product H1 work together to form cavities H1 and 12 for secondary molding. Slide it to the second position. Then, the primary molding for injecting into the cavities 13, 32 after taking out the molded product and the secondary molding for injecting into the cavities H1, 12 for secondary molding are simultaneously performed. Next, the secondary molded product is taken out, and the slide mold 10 is moved to the first position where the secondary molding cavities H1, 12 are formed in cooperation with the primary semi-molded product H1.
Then, the primary molding for injecting into the cavities 11 and 31 after taking out the molded product and the secondary molding for injecting into the cavities H1 and 12 for secondary molding are simultaneously performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a fixed mold, a movable mold, and a movable mold provided between these molds to form a primary semi-molded product by primary molding. A secondary molding method for molding and secondary molding to integrally mold a secondary semi-molded product into a primary semi-molded product to obtain a molded product, and a mold for secondary injection molding used for carrying out this molding method It is about.

[0002]

2. Description of the Related Art A hollow body product is formed as a half-hollow body or a divided body in a primary formation, the divided surfaces are abutted in the secondary formation, and the abutted portions are heated or welded to form one piece. Manufacturing hollow body products, D
The SI molding method, that is, the die sliding injection molding method is disclosed in Japanese Patent Publication No.
Proposed by No. 377. By applying the above-mentioned DSI molding method, a molded product composed of two kinds of resins, for example, a hard material and a soft material, is injected using a mold as shown in FIG. It can be obtained by molding. That is, FIG. 3A shows a mold for integrally molding a hemispherical second semi-molded product with a cubic first semi-molded product. , A movable mold K, and a slide mold S that slides between the molds F and K in the left-right direction in the drawing. A pair of first and second sprues a and b are formed on the fixed mold F at a predetermined interval. Similarly, a pair of first and second sprues c and d are also formed on the slide mold S. First
Sprue c communicates with a cavity e for molding a part of the first semi-molded product, and the second sprue d communicates with a cavity f for molding a hemispherical second semi-molded product. There is. In addition, a runner g having a predetermined length in the lateral direction is formed on the upper surface side of the slide mold S and communicates with the second sprue d. The movable mold K is provided with a cavity h for molding the lower half of the cubic first semi-molded product.

In order to mold a molded article made of different materials using the above-mentioned mold, as shown in FIG. 3B, the slide mold S is slid to the left first. To the position. Then, for example, a hard molten resin is injected from the first injection machine A. Then, the molten resin is filled from the first sprue a of the fixed mold F and the first sprue c of the slide mold S into the cavities e and h, and the cubic first semi-molded product is primarily molded. . Next, the movable mold K is opened, and the slide mold S is slid rightward to the second position. In this second position, as shown in FIG. 3C, the second sprue b of the fixed mold F is the runner g of the slide mold S.
And communicates with the cavity f through the second sprue d. Therefore, when the soft molten resin is injected from the second injector B, the hemispherical second semi-molded product is secondarily integrally molded on the first semi-molded product by the cavity f. Open the movable mold K and take out the molded product.

[0004]

A molded article composed of different materials can be obtained by the molding method using the above-mentioned mold. Moreover, since it can be molded by injection molding simply by sliding the slide mold S, there is an advantage that a molded product having a large bonding strength between different materials can be obtained. However, there are some problems to be improved. For example, when the primary molding is performed by the injection machine A, the injection machine B for secondary molding is closed, and conversely, when the secondary molding is performed by the injection machine B, the injection machine A is set to be closed. The cycle is long and the productivity cannot be improved. Also,
Since the injection is stopped, the molten resin stays and causes defective molding, which also causes an increase in defective rate. Therefore, the present invention provides a multiple injection molding method and a multiple injection molding method used for carrying out the method, in which the strength of the joint is large, the molding cycle is short, the productivity is high, and the defective molding rate is small. The purpose is to provide a mold.

[0005]

In order to achieve the above-mentioned object, the present invention uses a fixed mold, a movable mold, and a movable mold provided between these molds. When the primary semi-molded product is molded by primary molding and the secondary semi-molded product is molded integrally with the primary semi-molded product by secondary molding to obtain a molded product, to the cavity after taking out the molded product The primary molding for injection and the secondary molding for injection into the cavity for secondary molding, which is formed in cooperation with the primary semi-molded product molded by the primary molding, are simultaneously performed in the same mold, and Take out the molded product molded by the secondary molding, and then move the moving mold to the position where the cavity for the secondary molding is constructed in cooperation with the primary semi-molded product molded by the primary molding. ,
Next, the primary molding for injecting into the cavity after taking out the molded product and the secondary molding for injecting into the cavity for the secondary molding are simultaneously performed by the same mold, and the molded product molded by the secondary molding is performed. It is configured to repeat the above-mentioned operation of taking out and molding. According to a second aspect of the invention, in the molding method according to the first aspect, the movable mold is slidably moved between the fixed mold and the movable mold to mold the movable mold.
The invention according to claim 3 is configured such that, in the molding method according to claim 1 or 2, different resin materials are injected in the primary molding and the secondary molding. The invention according to claim 4 comprises a fixed mold, a movable mold, and a movable mold provided between these molds, and the fixed mold includes a pair of first and second molds. A sprue is provided, the movable mold is provided with at least three first, second, and third sprues and one cavity, and the movable mold is provided with at least two first and second cavities. When the movable mold is provided and moves to the second position, the first sprue of the fixed mold is moved to the second mold of the movable mold through the runner and the third sprue provided in the movable mold. Communicating with the cavity, the second sprue of the fixed mold is connected to the cavity of the movable mold and the first cavity of the movable mold through a runner and a second sprue provided in the movable mold. When the movable die moves to the first position while communicating with the The first sprue of the mold is communicated with the first cavity of the movable mold through the runner and the first sprue provided in the movable mold, and the second sprue of the fixed mold is It is configured to communicate with the cavity of the movable mold and the second cavity of the movable mold via a runner provided in the movable mold and a second sprue of the movable mold. According to a fifth aspect of the present invention, first and second runner stop projections are formed on the surface of the fixed mold facing the movable mold according to the fourth aspect, and the first runner stop projection is the movable mold. When the mold moves to the second position, the runner provided on the movable mold is closed, and the second runner stop projection is provided on the movable mold when the movable mold moves to the first position. The other runner is closed, and the invention according to claim 6 is such that the movable mold according to claim 4 or 5 is slidably driven between the fixed mold and the movable mold. Is composed of.

[0006]

Function: The moving die is moved to, for example, the second position. Then clamp the mold. Then, the first sprue of the fixed mold communicates with the second cavity of the movable mold through the runner and the third sprue provided in the movable mold, and the second sprue of the fixed mold moves. Via a runner and a second sprue provided in the mold, the cavity is made to communicate with the cavity of the moving mold and the primary semi-molded product molded by the previous primary molding. Therefore, the first of the fixed mold
The molten resin of, for example, a hard material is injected from the sprue, and the molten resin of a soft material is simultaneously injected from the second sprue. Then,
A primary semi-molded product is molded by the primary molding in the second cavity of the movable mold, and a secondary semi-molded product is integrally molded on the primary semi-molded product previously molded by the cavity of the movable mold. A semi-molded product is molded. After cooling and solidification, the movable mold is opened and a molded product composed of the primary semi-molded product and the secondary semi-molded product is taken out. The moving die is moved to the first position. Then clamp the mold. Then, the first sprue of the fixed mold communicates with the first cavity of the movable mold through the runner and the first sprue provided in the movable mold, and the second sprue is provided in the movable mold. The runner and the second sprue communicate with the cavity composed of the cavity of the moving mold and the primary semi-molded product molded by the previous primary molding. Therefore, similarly, the molten resin of the hard material is injected from the first sprue of the fixed mold and the molten resin of the soft material is simultaneously injected from the second sprue. Then, a primary semi-molded product is molded by the primary molding in the first cavity of the movable mold, and a secondary semi-molded product is integrally molded on the primary semi-molded product previously molded by the cavity of the movable mold. The second half molded product is molded. After cooling and solidification, the movable mold is opened and a molded product composed of the primary semi-molded product and the secondary semi-molded product is taken out. Hereinafter, the above operation is repeated to perform molding. In another invention, a movable mold is slidably moved between a fixed mold and a movable mold for molding, and in another invention, different resin materials are injected in primary molding and secondary molding.

[0007]

EXAMPLES According to the present invention, molded articles of various shapes can be molded, but in order to facilitate understanding, a cubic primary semi-molded article having a simple shape in primary molding is molded,
An example in which a hemispherical secondary semi-molded product is integrally molded on the primary semi-molded product by the secondary molding will be described. First, an example of the mold of the present invention will be described. As shown in FIG. 1A, the mold according to this embodiment includes a fixed mold 1, a movable mold 30 paired with the fixed mold 1, a movable mold 1 and a movable mold 30. It is composed of a slide mold 10 that is slidably driven in the left-right direction in the figure with the mold 30.

The fixed mold 1 is provided with a pair of first and second sprues 2 and 3 at predetermined intervals. Locate rings 4 and 5 are provided at the supply opening ends above the first and second sprues 2 and 3, and the locate ring 4 has the first
The nozzle of the injection machine A of No. 2 touches the locate ring 5, and the nozzle of the second injection machine B touches the locate ring 5. Further, on the lower surface of the fixed mold 1 facing the slide mold 20, first and second runner stop projections 6 and 7 are formed in the vicinity of both left and right ends in the drawing. The operation of these runner stop projections 6 and 7 will be described later in detail, but when the mold is clamped, for example, if the first runner stop projection 6 enters the projection receiving hole of the slide mold 30, the second runner stop projection 6 is stopped. The projection 7 enters the runner and closes the runner.

The slide mold 10 is provided with first and third cavities 11 and 13 for molding a part of the first semi-molded product on both sides. Further, a part of the first semi-molded product and a second cavity 12 for molding a hemispherical secondary semi-molded product are provided at a predetermined interval between the first and third cavities 11 and 13. It is provided. The first, second, and third cavities 11, 12, and 13 are communicated with the first, second, and third sprues 14, 15, and 16.

FIG. 1B is a schematic view of the upper surface of the slide mold 10 for showing the runner formed on the upper surface of the slide mold 10. As shown in FIG. On the upper surface of the slide mold 10, the slide mold 10
The first and second runner inlets 20 and 21 respectively aligned with the first and second sprues 2 and 3 of the fixed mold 1 when slid to the first position with respect to the fixed mold 1, and (a) of FIG. ),
Third and fourth runner inlets 24, 25 are formed that are aligned when slid to the second position shown in (b). Then, from the first runner entrance 20 to the first runner 2
2 extends rightward in an arc shape and communicates with the first sprue 14. From the second runner inlet 21, the second runner 2
3 extend in a zigzag manner so that the runners do not interfere with each other and communicate with the second sprue 15. Similarly, a third runner 26 extends leftward in an arc shape from the third runner inlet 24 and communicates with the third sprue 16. Further, a fourth runner 27 extends in a zigzag manner from the fourth runner inlet 25 so as not to interfere with each other, and communicates with the second sprue 15. Further, on the right side in the drawing of the upper surface of the slide mold 10, there is a first projection receiving hole 28 into which the first runner stop projection 6 of the fixed mold 1 is inserted when the slide mold 10 slides to the first position. Formed, and to the left, the second of the stationary mold 1 when the slide mold 10 slides to the second position.
The second projection receiving hole 29 into which the runner stop projection 7 of FIG.

The movable mold 30 is provided with first and second cavities 31, 32 for molding the lower half of the first semi-molded product at predetermined intervals. These first and second cavities 31, 32 are respectively aligned with the first and second cavities 11, 12 of the slide mold 10 when the slide mold 10 slides to the first position, and are shown in the figure. When slid to the second position, the second and third cavities 12 and 13 are respectively aligned.

Next, a method of molding a molded product composed of a cube and a hemisphere using the above mold will be described with reference to FIG. As shown in (a) and (b) of FIG. 2, the hard material has already been injected from the injection machine A into the first cavity 31 of the movable mold 30 in the previous molding cycle, and the first half of the cube has been injected. A description will be given from the time when the molded product H1 is molded. The mold is clamped in the state of the second position shown in FIG. Then, the first sprue 2 of the fixed mold 1 is in communication with the third runner inlet 24 of the slide mold 10, and the second sprue 3 is in communication with the fourth runner inlet 25 of the slide mold 10. . At the same time, the second runner stop projection 7 of the fixed mold 1
Although it enters the second protrusion receiving hole 29 of the slide mold 10,
Runner stop projection 6 of the second runner 23 enters the second runner 23
The runner 23 is closed.

Therefore, for example, a hard material is injected from the nozzle of the first injection machine A, and a soft material is injected from the nozzle of the injection machine B at respective speeds. The hard injection material injected from the injection machine A includes the first sprue 2 of the fixed mold 1, the third runner inlet 24 of the slide mold 10, and the third runner 2.
6 and the third sprue 16 to be injected into a cavity composed of the third cavity 13 of the slide mold 10 and the second cavity 32 of the movable mold 30. Therefore, by this cavity, the cubic primary semi-molded product H1 is primarily molded. The soft injection material injected from the second injection machine B passes through the second sprue 3 of the fixed mold 1, the fourth runner inlet 25 of the slide mold 10, the fourth runner 27, and the second sprue 15. It is injected through the second cavity 12 of the slide mold 10, that is, the cavity for secondary molding composed of the primary semi-molded product H1 and the second cavity 12. Therefore, the hemispherical secondary semi-molded product H2 is integrally secondary-molded on the cubic primary semi-molded product H1.
After cooling and solidification, the movable mold 30 is opened. Although not shown in the figure, the ejector pin projects and the molded product is taken out.

1 for the second cavity 32 of the movable mold 30.
The slide mold 10 is slid to the first position shown in (c) and (d) of FIG. 2 while leaving the next half-molded product H1. Then, the first and second cavities 11 and 12 of the slide mold 10 are aligned with the first and second cavities 31 and 32 of the movable mold 30, respectively. Further, the first sprue 2 of the fixed mold 1 is aligned with the first runner inlet 20 of the slide mold 10, and the second sprue 3 of the fixed mold 1 is aligned with the second runner inlet 21. Then the mold is clamped. Then, the first runner stop projection 6 of the fixed mold 1
Enters the first projection receiving hole 28 of the slide mold 10 and the second runner stop projection 7 enters the fourth runner 27 to close the fourth runner 27.

Inject as described above, take out the molded product,
Then, while the slide mold 10 is slid and clamped, the injection machines A and B are weighed for the next injection, so that the injection machines A and B eject as described above. The hard injection material injected from the injection machine A passes through the first sprue 2 of the fixed mold 1, the first runner inlet 20, the first runner 22 and the first sprue 14 of the slide mold 10. It is injected into a cavity composed of the first cavity 11 of the slide die 10 and the first cavity 31 of the movable die 30. Therefore, these cavities 11, 31
As a result, a cubic primary semi-molded product H1 is primarily formed. The soft injection material injected from the injection machine B includes the second sprue 3 of the fixed mold 1 and the second runner inlet 2 of the slide mold 10.
It is injected through the first and second runners 23 and the second sprue 15 into a cavity for secondary molding composed of the second cavity 12 of the slide mold 10 and the primary semi-molded product H1. Therefore, the hemispherical secondary semi-molded product H2 is secondarily integrally formed on the cubic primary semi-molded product H1. After cooling and solidification, the movable mold 30 is opened. The ejector pin projects and the molded product is taken out. Hereinafter, the above molding cycle is repeatedly molded.

The present invention can be implemented in various forms. For example, in the above-described molding example, injection materials having different hardness are injected from the injection machines A and B, but injection materials having the same material but different colors can be injected to obtain a molded product. It is also clear that injection materials with the same material and color can be injected. Although the slide mold 10 is applied in the embodiment of the mold, the slide mold 10 may be replaced by a rotary mold rotating in the space between the fixed mold 1 and the movable mold 30. . In addition, the slide mold 10 has a first part for molding a part of the primary semi-molded product,
Although a few cavities 11, 12, and 13 are provided, if the first semi-molded product is molded by the movable mold 30, the first and third cavities 11 and 13 are unnecessary. Furthermore, the slide mold 10 has three first, second,
Three sprues 14, 15, 16 are provided, and these three first, second, third sprues 14, 15, 16 are movable molds 3.
As is apparent from the fact that the first and second cavities 31 and 32 of 0 are alternately aligned, the slide mold 10 has, for example, 6 sprues, and the movable mold 30. It is also possible to provide four cavities and to similarly inject from the first and second sprues 2 and 3 of the fixed mold 1 to obtain two molded products at the same time.

[0017]

As described above, according to the present invention, a fixed mold, a movable mold, and a movable mold provided between these molds are used, and primary molding is performed to obtain a primary half. When the molded product is molded and the secondary semi-molded product is integrally molded with the primary semi-molded product by the secondary molding to obtain the molded product, the primary molding for injecting into the cavity after taking out the molded product, Simultaneously perform the secondary molding, which is formed by cooperating with the primary semi-molded product molded by the primary molding, into the cavity for the secondary molding, using the same mold, and molded by the secondary molding. Remove the molded product, then move the moving mold to the position where the cavity for secondary molding is constructed in cooperation with the primary semi-molded product molded by primary molding, and then remove the molded product. After injection, the primary molding is injected into the cavity, and the secondary molding is injected into the cavity. Secondary molding is performed at the same time with the same mold, and the molded product obtained by secondary molding is taken out. By repeating the above operation, it is possible to perform simultaneous molding without waste in molding with two injection machines. Further, the effect peculiar to the present invention that the molding cycle is shortened and the productivity is improved can be obtained. Moreover, since there is no injection machine that simultaneously injects and pauses, there is no resin stagnation, and molding can be performed with a low defective molding rate. According to another invention, since the movable die is slidably moved between the fixed die and the movable die to form, the sliding movement has a shorter movement distance than the rotational movement even with the same movement, The molding cycle can be further shortened. Further, the mold can be easily manufactured and the movable mold can be easily aligned with the fixed mold or the movable mold. Further, since the moving range can be narrowed as compared with the rotational movement, the effect that the mold can be made compact can be obtained. Further, according to another invention, different resin materials are injected in the primary molding and the secondary molding, so that the effect of obtaining a molded product made of a different material having high bonding strength is added.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a secondary molding die according to the present invention, in which (a) is a schematic cross-sectional view thereof and (b) is a schematic plan view of a slide die.

FIG. 2 is a view showing a state of being molded by a secondary molding die according to the present invention, in which (a) is a sectional view schematically showing a molding state when the slide die is at the second position. , (B) is a schematic plan view of the slide mold at that time, (C) is a sectional view schematically showing the molding state when the slide mold is in the first position, and (D) is that time 3 is a schematic plan view of the slide mold of FIG.

FIG. 3A is a sectional view showing an example of a mold for obtaining a molded product from primary molding and secondary molding, and FIG. 3B is a sectional view showing a state where primary molding is performed, It is sectional drawing which shows the state which is (c) secondary molding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed mold 2, 3 1st, 2nd sprue 6, 7 1st, 2nd runner stop projection 10 Slide mold 11, 12, 13 1st, 2nd, 3rd cavities 14, 15, 16 1st, 2nd 3 sprue 22, 23 1st, 2nd runner 26, 27 3rd, 4th runner 30 Fixed mold 31, 32 1st, 2nd cavities

Claims (6)

[Claims] 1. A fixed mold (1) and a movable mold (30).
And a moving mold (10) provided between these molds (1, 30) are used to mold a primary semi-molded product (H1) by primary molding and Next half molded product (H
When 2) is integrally molded with the primary semi-molded product (H1) to obtain a molded product, primary molding in which the molded product is taken out and injected into the cavities (13, 32) and molding by primary molding Simultaneous with the same molding (1, 10, 30) and the secondary molding that is injected into the cavity (H1, 12) for secondary molding that is formed in cooperation with the primary semi-molded product (H1). Then, take out the molded product molded by the secondary molding,
Then, the moving mold (10) is moved to a position where the cavity (H1, 12) for secondary molding is formed in cooperation with the primary semi-molded product (H1) molded by primary molding, , Cavity after removing the molded product (11, 3
The primary molding for injection into 1) and the secondary molding for injection into the cavity (H1, 12) for secondary molding are made in the same mold (1,
10 and 30) are carried out simultaneously, and the molded article molded by the secondary molding is taken out, and the above-mentioned operation is repeated to carry out molding, and the multiple injection molding method is characterized. 2. The injection molding method according to claim 1, wherein the movable mold (10) is slidably moved between the fixed mold (1) and the movable mold (30) to mold. Method. 3. The molding method according to claim 1, wherein a different resin material is injected in the primary molding and the secondary molding. 4. A fixed mold (1) and a movable mold (30).
And a movable mold (10) provided between these molds (1, 30), and the fixed mold (1) includes a pair of first and second sprues (2, 3). ) Is provided, and the movable mold (10) has at least three first, second, and third sprues (14, 15, 1).
6) and one cavity (12) are provided, the movable mold (30) is provided with at least two first and second cavities (31, 32), and the movable mold (10) is provided. Is moved to the second position, the first sprue (2) of the fixed mold (1) passes through the runner (26) and the third sprue (16) provided in the movable mold (10). Communicating with the second cavity (32) of the movable mold (30), and the second sprue (3) of the fixed mold (1) is a runner (provided on the movable mold (10). 27) and a second sprue (15) communicate with the cavity (12) of the movable mold (10) and the first cavity (31) of the movable mold, and the movable mold (10). Is moved to the first position, the first sprue (2) of the fixed mold (1) moves forward. The fixed mold (1) communicates with the first cavity (31) of the movable mold (30) through the runner (22) and the first sprue (14) provided in the movable mold (10). The second sprue (3) of the movable die (3) is provided via the runner (23) provided in the movable die (10) and the second sprue (15) of the movable die (10). A multi-injection molding die, characterized by communicating with the cavity (12) of 10) and the second cavity (32) of the movable die (30). 5. A fixed mold (1) according to claim 4, wherein first and second runner stop projections (6, 7) are formed on the surface of the fixed mold (1) facing the movable mold (10), Runner stop protrusions (6)
Closes the runner (23) provided on the movable die (10) when the movable die (10) moves to the second position, and the second runner stop projection (7) moves the movable runner (23). When the mold (10) moves to the first position, the moving mold (1
0) A multiple injection molding die for closing the other runner (27) provided in (0). 6. The movable die (1) according to claim 4 or 5.
Reference numeral 0) is a multi-injection molding die which is a slide die (10) slidably driven between a fixed die (1) and a movable die (30).