JPH0426290B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a multicolor molding method for integrally molding a first molded product and a second molded product.

[Conventional technology]

For example, as shown in Japanese Patent Publication No. 50-32253, a so-called multicolor molding method in which a first molded product and a second molded product are integrally molded is a method in which a movable plate is attached horizontally to a fixed plate of the main body frame. The first and second female molds are mounted on this movable plate at a predetermined interval in the front-rear direction. In order to mold the first molded product, for example, in the molding space between the clamped first female mold and male mold, a Synthetic resin is centrally injected and molded from a first injection device having an axis, and then, after these molds are opened, a movable plate is moved laterally to form a male mold that holds the first molded product. After the molds are clamped with the second female mold facing each other, the first injection molding is performed on the main body frame into the molding space between the second female mold and the male mold holding the first molded product. The synthetic resin is centrally injected from a second injection device disposed in a direction inclined to the axis of the apparatus, and the second molded product is integrally molded into the first molded product.

[Problem to be solved by the invention]

However, in the multicolor molding method described above, since the movable platen is moved back and forth in the lateral direction, a part of the movable platen (first and second Since the female mold (the part where the female mold is attached) protrudes, it requires a lot of installation space, and it is also difficult to secure space to install an ejection device that enters from the side of the mold and automatically ejects the molded product. I couldn't do it. Therefore, with such a molding method, it has not been possible to systemize the molding machine and a general-purpose type take-out device in combination. In addition, in such a molding method, two injection devices are arranged on the main body frame and center injection is performed into the first and second female molds, so the molding machine itself is suitable for multicolor molding. As a result, the equipment itself has become larger and more expensive. Unfortunately, the molding machine became a specialized machine, and the cost of the molding machine itself became extremely high.The molding cost per mold was high, and the operating efficiency of the multi-color molding machine was poor. The present invention was invented to solve the above-mentioned conventional drawbacks, and its purpose is to utilize an existing molding machine by combining a center injection molding method and a parting injection molding method. It is an object of the present invention to provide a multicolor molding method that allows multicolor molding and significantly reduces molding costs. Another object of the present invention is to perform multicolor molding by moving the movable plate to its upper and lower limit positions, thereby positioning each female mold to face the male mold. The purpose of the present invention is to provide a multicolor molding method that allows for

[Means to solve the problem]

A movable plate is supported movably in the vertical direction by a fixed side support plate provided on the main body frame, while a movable side support plate is movably supported by the main body frame when the movable plate moves to the upper movement limit position. The first female mold is attached to a position that matches the male mold attached to the holder, and the second female mold is attached to a position that matches the male mold when the movable plate moves to the lower limit position. After the movable plate of the mold is moved upwards or downwards so that one of the female molds faces the male mold and the molds are clamped, one of the female molds and the male mold are released from the first injection device. A first molding process in which a synthetic resin is injected into the molding space to mold a first molded product, and after opening one of the female and male molds, the movable plate is moved downwards opposite to the above. Alternatively, after moving upward and clamping the female mold holding the first molded product and the other female mold so that they face each other, the second injection device connects the male mold and the other female mold. a second molding step in which a synthetic resin is injected into the molding space and a second molded product is integrally molded on the first molded product held in the male mold; One of the injection devices is a center injection type injection device attached to the main body frame with its axis aligned with the machine center, and the other injection device has its axis aligned with the axis perpendicular to the other injection device. It is characterized by comprising a parting injection type injection device disposed on the side of the main body frame corresponding to the mating surface of the male mold and the female mold.

【Example】

The method of the present invention will be explained below using an example of its apparatus. FIG. 1 is a schematic perspective view of a molding machine showing an example of an apparatus embodying the method of the present invention, and FIG. 2 is a schematic perspective view showing a slide mechanism on the female mold side. A fixed side support plate 5 is provided upright on the right side of the center of the main body frame 3 of the molding machine 1. Furthermore, a movable side support plate 7 is erected on the left side of the central part of the main body frame 3 so as to face the fixed side support plate 5, and between these fixed side support plate 5 and movable side support plate 7 there are four Guide rods 9 are mounted at diagonal positions. A movable platen 11 is supported on the guide rod 9 so as to be movable in the axial direction, and the movable platen 11 is supported by a mold clamping cylinder 12 attached to the movable support plate 7.
It is moved between a mold-clamping position close to the fixed-side support plate 5 and a mold-opening position spaced apart from the fixed-side support plate 5. A first injection device 13 is fixed to the upper right side of the main body frame 3 so as to have its axis in a direction that coincides with the moving direction of the movable platen 11. The first injection device 13 has a built-in injection screw (not shown) and a heating cylinder 13a that melts the synthetic resin and pressurizes it to a predetermined pressure. Through hole 5a provided in 5
is inserted into the A support frame 15 extending in the vertical direction is attached to the fixed support plate 5 facing the movable plate 11, and a through hole 15a is formed in the support frame 15 so as to match the through hole 5a of the fixed support plate 5. There is. A movable plate 17 is supported by the support frame 15 so as to be movable in the vertical direction, and the movable plate 17 is moved between an upper position and a lower position of the support frame 15 by a hydraulic cylinder 23 attached to the main body frame 3. Ru. This movable plate 17 has a first female die 19, a male die 25 (described later), and a second female die 2 when the movable plate 17 moves to the lower limit position.
1, when the movable plate 17 moves to the upper limit position,
They are attached so as to face the male molds 25, respectively. In addition, a movable platen 11 facing the fixed side support plate 5
One male mold 25 is attached to , and when the movable plate 17 is moved to the lower position with the hydraulic cylinder 23 inactive, the upper first female mold 19 and the male mold 25 are Further, when the movable plate 17 is moved to the upper position by the operation of the hydraulic cylinder 23, the lower second female mold 21 and the male mold 25 are opposed to each other. Further, a through hole 17a is formed in the movable plate 17 according to the mounting position of the first female mold 19 so as to coincide with the through hole 5a and the through hole 15a. A second injection device 27 is disposed on the side of the main body frame 3 injected into the second female mold 21 so as to have its axis in a direction perpendicular to the axis of the first injection device 13 . This second injection device 27 includes a heating cylinder 27 in which an injection screw (not shown) is built-in.
a, and the nozzle portion 27b at the tip thereof is moved toward (the mating surface) of the second female mold 21 and the male mold 25. Next, the multicolor molding method using the above-mentioned device example will be described in a third manner.
This will be explained with reference to FIGS. In the non-operating state of the hydraulic cylinder 23,
The first female mold 19 is moved and positioned to face the male mold 25 by the movable plate 17 that has been moved to the lower position. The mold clamping cylinder 12 operating in this state causes the male mold 25 to close to the first female mold 1.
9, the nozzle portion 13b of the first injection device 13 is inserted through the through hole 5a, the through hole 15a, and the through hole 17a and is pressed against the sprue 19a of the first female mold 19. Male mold 2 shown in Figure 3
A synthetic resin is injected into the molding space between the mold 5 and the first female mold 19, and a first molded product 29a shown in FIG. 6 is center injection molded. Next, after a predetermined curing time has elapsed, the contact between the sprue 19a and the nozzle portion 13b of the first female mold 19 is released, and the mold clamping cylinder 12, which moves back, closes the first female mold 19. From male mold 25
are spaced apart. At this time, the first molded product 29a is held within the male mold 25. When the hydraulic cylinder 23 is operated in this state, the second female mold 21 is positioned to face the male mold 25 by the movable plate 17 which has moved upward as shown in FIG. The male mold 25 holding the first molded product 29a is clamped to the second female mold 21 by the operation of the mold clamping cylinder 12. In this state, the second injection device 27 connects its nozzle portion 27b to the second
After the female mold 21 and the male mold 25 are brought into pressure contact with a sprue 21a provided on the mating surface (parting surface), the second female mold 21 is connected via this sprue 21a.
When the synthetic resin is injected into the molding space between the mold and the male mold 25, the second molded product 29b shown in FIG.
Parting injection molding is performed integrally with the molded product 29a to form the molded product 29. After the above-described operation, when a predetermined curing time has elapsed, the contact between the sprue and the nozzle portion 27b on the parting surfaces of the second female mold 21 and the male mold 25 is released, and the mold moves back. The second female die 21 and the male die 25 are opened by the tightening cylinder 12. At this time, a molded product 2 in which the first molded product 29a and the second molded product 29b are integrally molded.
9 is held within the male mold 25, and is ejected from the male mold 25 by an ejecting mechanism (not shown) that operates in conjunction with the mold opening operation to complete molding. In this way, the method of this embodiment integrally molds the molded product 29 by combining center injection molding and parting injection molding. The first molded product 29a and the second molded product 29b
The molded product 29 consisting of the above can be integrally molded, and multicolor molding can be performed without using a special machine, and molding costs can be reduced. Moreover, an existing center injection molding machine can be used as a multicolor molding machine, and molding efficiency can be improved.

【Effect of the invention】

Therefore, the present invention enables multi-color molding using an existing molding machine by combining the center injection molding method and the parting injection molding method, significantly reducing molding costs, and moving the movable plate to its upper limit of motion. It is possible to provide a multicolor molding method that allows multicolor molding to be performed by positioning each female mold to face the male mold by moving the female mold to the lower limit position.

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing a molding machine that embodies the method of the present invention, FIG. 2 is a schematic perspective view showing a slide mechanism on the female mold side, and FIGS. 3 to 6 are It is an explanatory diagram showing an effect. In the figure, 1 is a molding machine, 3 is a main body frame, 5 is a fixed side support plate, 7 is a movable side support plate, 13 is a first injection device, 17 is a movable plate, 19 is a first female mold, 21
25 is a male mold, 27 is a second injection device, 29 is a molded product, and 29a and 29b are first and second molded products.

Claims (1)

[Claims] 1. A movable plate that is supported movably in the vertical direction by a fixed side support plate provided on the main body frame, and is movable to the main body frame when the movable plate moves to the upper movement limit position. The first mold is attached to the same position as the male mold attached to the supported movable support plate.
Of the female mold and the second female mold attached to the position that coincides with the male mold when the movable plate moves to the lower limit of movement position, move the movable plate upward or downward and select one of them. After the female mold is opposed to the male mold and the molds are clamped, synthetic resin is injected from the first injection device into the molding space between the female mold and the male mold to form the first molded product. A first molding step of molding, and a female mold holding the first molded product by moving the movable plate downward or upward opposite to the above after opening one of the female mold and male mold. After the molds are clamped with the male mold and the other female mold facing each other, a synthetic resin is injected into the molding space between the male mold and the other female mold from a second injection device, and the mold is held in the male mold. and a second molding step in which a second molded product is integrally molded on the first molded product, and one of the first and second injection devices has its axis aligned with the center of the machine. It consists of a center injection type injection device attached to the main body frame, and the other injection device has an axis in a direction perpendicular to one injection device, and the injection device A multicolor molding method comprising a parting injection type injection device placed on the side of a main body frame.