JPH04331123A - Die slide type mold structure for injection molding - Google Patents

Abstract

PURPOSE:To produce a product by mold clamping and mold opening of one time and to enhance productivity by parallel providing two slide molds having a female mold and a male mold and forming the half bodies by the respective slide molds and thereafter moving the slide molds to a second position to join both half bodies. CONSTITUTION:In the case of setting both slide molds 22 in a first mold clamping position and advancing a movable mold 20, the female and male mold parts 202, 201 of the movable mold 20 are mold-matched with the male and female mold parts 221, 222 of one side of slide mold 22 to form a cavity having the shape of a half body W. Further in the other side of slide mold 22, the male mold part 201 is mold-matched with the female mold part 221 to mate the right and left half bodies W. In this stare, molten resin is introduced into the cavity of one side of slide mold 22 from a nozzle to form the right and left half bodies W. Together therewith, molten resin is introduced into the cavity of the other side of slide mold 22. The mating parts of the right and left half bodies W are joined to produce a hollow product. Thereafter the respective slide molds 22 are moved to a second mold clamping position to perform molding reverse to the above-mentioned method.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die structure for sliding die injection molding, and more particularly to a structure capable of maintaining a constant injection amount each time.

0002

BACKGROUND OF THE INVENTION When producing synthetic resin products, blow molding or injection molding are generally used.

For example, when manufacturing a hollow product using a blow molding method, the molten resin is extruded into a cylindrical parison using an accumulator head, both sides of the parison are sandwiched between molds, and air is blown into the inside to form the hollow product. In this case, relatively large burrs are formed on the top and bottom of the product due to the mold, and a nozzle hole for blowing air remains on the product, resulting in a completely sealed hollow product. Moreover, it is difficult to manufacture to a uniform thickness.

[0004] On the other hand, when manufacturing hollow products using the injection molding method, a method is adopted in which the hollow molded product is divided into two parts, the left and right halves are each injection molded, and the two halves are abutted and joined. However, in this case, there is an advantage that completely sealed hollow products and hollow products with complex shapes can be successfully manufactured.

For example, as shown in Japanese Unexamined Patent Publication No. 62-87315, a slide mold is provided between a fixed mold and a movable mold, and the movable mold and the slide mold are placed in the first mold clamping position, and the male and female of both are placed in the first clamping position. A pair of half bodies is manufactured by injecting molten resin into the cavity formed by the mold part, and then the slide mold is slid to set the movable mold and the slide mold to the second mold clamping position, and the half bodies are manufactured. A die slide injection molding method is known in which the two halves are joined by abutting the two halves and injecting molten resin into the abutting portion.

[0006]

However, in the die slide injection molding method described in the above-mentioned conventional publication, the left and right halves are molded by primary injection, and the abutting portions of the halves are molded by secondary injection after mold sliding. The amount of injected resin differs significantly between the primary injection and the secondary injection.
There have been problems in that it is difficult to adjust the injection amount for each injection molding, it is difficult to manage the injection amount, and it is also difficult to deal with this in terms of equipment.

In view of these points, the present invention provides a die-sliding injection mold that makes it possible to keep the injection amount constant each time and to produce one finished product for each injection. The challenge is to provide structure.

[0008]

[Means for Solving the Problems] Therefore, in the die-sliding mold structure for injection molding according to the present invention, first and second slide molds each having a female mold part and a male mold part arranged in the sliding direction mutually slide. On the other hand, a non-sliding mold 20 is provided in which male mold parts and female mold parts are arranged in two rows corresponding to the first and second sliding molds. is provided with a driving source that slides each of them by a predetermined pitch independently of each other, and the sliding surfaces of the first and second slide molds are provided with a drive source that is coaxial with the injection nozzle at the first and second mold clamping positions, respectively. A plurality of half-sprues are provided to form the upper sprue, and the mold-splitting surfaces of the first and second sliding molds and the non-sliding mold are supplied from the sprue formed by the pair of half-sprues. The gist is that a runner is formed for supplying molten resin to each female mold part in a state where the molds are matched.

[0009] When injection molding is performed using the die slide injection mold having the structure according to the present invention, the first and second
At the first mold clamping position of both sliding molds, the first sliding mold and the non-sliding mold perform primary injection of the right half body and the left half body, and the second sliding mold and the non-sliding mold perform primary injection of the right half body and the left half body. Both halves are joined, both the first and second sliding molds are slid to the second mold clamping position, the left and right halves are joined with the first sliding mold and the non-sliding mold, and the second A sliding type and a non-sliding type are used to perform primary injection of the right half body and the left half body.

0010

[Operation] First, both slide molds are set to the first mold clamping position,
The male and female mold parts of the first sliding mold and the corresponding male and female mold parts of the non-sliding mold, and the female mold part of the second sliding mold and the female mold part of the non-sliding mold are respectively matched to form one nozzle. When resin is injected toward the sprue formed between the sliding surfaces of the first and second slide molds, the molten resin is supplied to each female mold in the first slide mold through a runner that communicates with the sprue. A right half body and a left half body are molded, and the second sliding mold is supplied with molten resin through a runner that communicates with the sprue, and both the first sliding mold and the non-sliding female mold are molded. Molten resin is supplied to the abutment area between the right half body and the left half body within the chamber to join them together, producing a hollow product.

Next, when the mold is opened and the hollow product etc. is ejected, both slide molds are slid from the first mold clamping position to the second mold clamping position, and when the mold is clamped, the above case is different. Conversely, the male and female mold parts of the second sliding mold and the corresponding male and female mold parts of the non-sliding mold, and the female mold part of the first sliding mold and the female mold part of the non-sliding mold are mold-matched, respectively. result,
The left and right halves are molded using the second slide mold, and the two halves are joined using the first slide mold.

[0012] In this way, at both the first and second mold clamping positions, the molding of the left and right halves and the joining of the halves are performed simultaneously, so that the amount of molten resin injected is constant each time. becomes.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below based on specific examples shown in the drawings.

FIGS. 1 to 5 show a die structure for sliding die injection molding according to an embodiment of the present invention. In FIG. 1, a mounting frame 11 is provided on a bed 10 of an injection molding machine 1, a die slide type mold 2 is supported on the mounting frame 11, and a molten resin injection mechanism 3 is mounted on the bed 10. is disposed facing the mold 2, and the injection mechanism 3 includes a hopper 30 for storing molten resin, a nozzle 31 for injecting the molten resin, a pressurizing cylinder 32, and a drive device 33 for moving the nozzle 31 forward and backward. There is.

Next, the structure of the mold 2 will be explained in detail. The mold 2 has two sliding molds 22A and 22B between the movable mold 20 and the fixed mold 21 as shown in FIGS. 2 and 3. A female part 221 and a male part 222 are formed in the sliding direction on the molding surfaces of both slide molds 22, and a first, male mold part 222 is formed on the molding surface of the movable mold 20. 2nd slide type 2
Two rows of male mold parts 202 and female mold parts 201 are formed corresponding to the male and female mold parts 221, 222 of 2A and 22B, and the male and female mold parts 201, 202, 222, 221 are matched. On the other hand, the two female mold parts 201 and 221 are molded together to form a cavity for joining the two halves together. .

First and second half sprues 223A, 22
4A, 223B, and 224B are provided at a pitch equal to the slide stroke of the first and second slide molds 22A and 22B, respectively, and shifted by a half pitch with respect to the mold part, and at the first mold clamping position shown in FIG. , first slide mold 2
2A second half sprue 224A and second slide mold 22
In the second mold clamping position shown in FIG. 3, the first half sprue 223A of the first slide mold 22A and the second half sprue of the second slide mold 22B match. 224B to form one sprue 210.

As described above, the position of the sprue 210 formed at both the first and second mold clamping positions remains unchanged, and the sprue 210 is connected to the injection nozzle 31 (see FIG. (see) to supply the molten resin. In addition, L-shaped and T-shaped runners 225A and 2
26A; 225B, 226B are provided starting from each half sprue 223A, 224A, 223B, 224B, respectively.

As shown in FIG. 4, which is a cross-sectional view taken along the line A--A in FIG. Submarine gates 227 and 227 are respectively provided so that the molten resin can be distributed and supplied to the molds 221, so that the two half bodies W and W can be molded simultaneously on the first slide mold 22A side.

Further, as shown in FIG. 5, which is a cross section taken along the line B-B in FIG.
The L-shaped runner 225B is mold-matched with the female mold part 221 of B, and the L-shaped runner 225B can supply molten resin to the two halves W, W that are brought together via the side gate 228. There is. T-shaped runner 226 of second slide type 22B
B and the L-shaped runner 225A of the first slide type 22A,
Similarly to the above, the submarine gate and the side gate make it possible to supply molten resin when necessary, that is, at the second mold clamping position.

Furthermore, the mold 2 is provided with die slide cylinders 23 for sliding both slide molds 22, respectively.
A mold opening/closing cylinder 24 for opening and closing the movable mold 20 is also provided.

Next, the manufacturing method will be explained. When manufacturing a hollow product, first, both slide molds 22 are set to the first mold clamping position shown in FIG.
The male and female mold parts 221, 222 of the movable mold 20 and the male and female mold parts 202, 201 of the movable mold 20 are matched as shown in FIG. The female mold part 221 of the slide mold 22 and the female mold part 20 of the movable mold 20
1 are mold-matched as shown in FIG. 5, and the left and right halves W are abutted.

Next, the drive device 33 is activated to move the nozzle 31
is advanced, the pressurizing cylinder 32 is operated, and the hopper 3
The molten resin within 0 is injected. Then, the molten resin is injected into the cavity of the first slide mold 22A through the sprue 210, the T-shaped runner 226A, and the submarine gates 227, 227, and the left and right half bodies W, W are manufactured, and at the same time, the sprue 210, L It is injected into the cavity of the second slide mold 22B via the letter-shaped runner 225B and the side gate 228, and the abutting parts of the left and right halves W are joined to produce a hollow product. When the molding is completed, the nozzle 31
At the same time, the mold opening/closing cylinder 24 is operated to open the movable mold 20 and eject the manufactured hollow product.

When the mold opening and ejection are completed in this way, both slide molds 22A and 22B are slid from the first mold clamping position to the second mold clamping position shown in FIG. On the contrary, the second slide type 2
The male and female mold parts 221 and 222 of the first slide mold 2B and the corresponding male and female mold parts 202 and 201 of the movable mold 20 are matched as shown in FIG. The female mold parts 201 of 20 are mold-aligned as shown in FIG. 5, and then molten resin is injected in the same manner as described above to manufacture left and right half bodies W and a hollow product.

In the die slide injection mold structure of this embodiment as described above, two slide molds 22 are combined in parallel, and the left and right halves W are molded in one injection, and
Since the halves W are joined together, the amount of molten resin injected at one time can be kept constant each time, and the complicated adjustment of the injection amount as in the conventional method can be eliminated.

Furthermore, in the die structure for slide injection molding of this embodiment, one hollow product can be produced by one mold-clamping and mold-opening operation, and one hollow product can be produced by two mold-clamping and mold-opening operations as in the conventional method.
Work efficiency can be greatly improved compared to manufacturing one product.

[0026]

As described above, according to the die slide injection mold structure according to the present invention, two slide molds having a female part and a male part are provided in parallel, and the first position of the slide mold is With a single injection, one slide mold molds the left and right halves, the other slide mold joins the halves, the slide mold is slid to the second position, and the other slide mold is molded with a single injection. By molding the left and right halves, and joining the halves with one slide mold, the amount of molten resin injected each time can be kept constant, and the product can be molded with just one mold clamping and mold opening. One product can be manufactured, which has the effect of improving productivity.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an injection molding machine equipped with a die slide injection mold having a structure according to an embodiment of the present invention.

FIG. 2 is a plan configuration diagram showing the die structure for die slide injection molding in a first mold clamping position.

FIG. 3 is a plan configuration diagram showing the die structure for die slide injection molding in a second mold clamping position.

FIG. 4 is a cross-sectional view taken along line A-A in FIG. 2.

FIG. 5 is a cross-sectional view taken along line BB in FIG. 2.

[Explanation of symbols]

20 Movable mold 201 Female part 202 Male part 22A, 22B First and second slide molds 221 Female part 222 Male part 210 Sprue, 223A, 224A, 223B, 224B Half sprue 225A, 226A, 225B, 226B Runner .

Claims (2)

[Claims] Claim 1: First and second slide molds having a female mold part and a male mold part disposed in the sliding direction are provided in sliding contact with each other so as to be freely slidable, while corresponding to the first and second slide molds. A non-sliding die 20 having two rows of male and female parts is provided, and the first and second sliding dies are each provided with a drive source that slides each one by a predetermined pitch independently of each other, Each sliding surface of the first and second slide molds is provided with a plurality of half sprues for forming sprues located coaxially with the injection nozzle at the first and second mold clamping positions, respectively. 1. The mold dividing surfaces of the second sliding mold and the non-sliding mold are provided with a mold for supplying molten resin supplied from a sprue formed by a pair of half sprues to each female mold part in a mold-matched state. A die-sliding type injection mold structure characterized by the formation of a runner. [Claim 2] At the first mold clamping position of both slide molds, the first
The male and female mold parts of the sliding mold 20 are matched with the corresponding male and female mold parts of the non-sliding mold 20 to primary inject the right half body and the left half body. The female mold part and the corresponding female mold part of the non-sliding mold are matched to join the two halves W, and both sliding molds 22 are slid to the second mold clamping position, and the female mold of the first sliding mold is and the corresponding female mold part of the non-sliding mold to join the left and right halves W, and the male and female mold parts of the second sliding mold and the corresponding male and female mold parts of the non-sliding mold. 2. The die-sliding mold structure for injection molding according to claim 1, wherein the right half body and the left half body are primarily injected by matching the molds.