JPH03219932A - Double injection molding method - Google Patents

Abstract

PURPOSE:To mold efficiently a molded product of a long-sized matter while contriving miniaturization and weight reduction of an injection device, by a method wherein after the first movable mold and a single stationary mold are clamped down on each other by confronting them with each other by following a movement of a movable member and synthetic resin is injected within a molding space between the first movable mold and stationary mold with the first injection device. CONSTITUTION:When a mold clamping cylinder is actuated, the second movable mold 23 is clamped down a stationary mold 25 holding the first molded product 41. In this instance, the first molded product 41 is positioned within the second molding space 47 formed of the second movable mold 23 and stationary mold 25. Then when the second injection stand is moved toward the rear of the stationary mold 25 with the actuating second cylinder 31, an injection nozzle of the second injection device 29 is pressure-contacted to a sprue 49 of the stationary mold 25. Then when molten synthetic resin is injected within the molding space 47 through the injection nozzle of the second injection device 29, the second molded product 51 is molded while the same is being fused integrally with the first molded product 41 and a product 53 is molded.

Description

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

The present invention relates to a double injection molding method for integrally molding at least two different types of molded products.

[Prior art]

The present applicant previously proposed in Japanese Patent Application No. 60-299212 that of first and second fixed molds attached to a support member that moves up and down, the first fixed mold was opposed to the movable mold. After that, a first injection step of injecting a synthetic resin into a first fixed mold and a movable mold clamped by a first injection device to form a first molded product; After the injection process, a mold opening process in which the first fixed mold and the movable mold are opened, and a fixed mold in which the second fixed mold is opposed to the movable mold as the support member moves up and down. a second step of integrally molding a second molded product into the first molded product by injecting synthetic resin into the clamped movable mold and the second fixed mold using a second injection device; A double injection molding method consisting of two injection processes was proposed.

[Problem to be solved by the invention]

However, in the double injection molding method described above,
The support member to which the first and second fixed molds are attached is moved up and down, and the movable mold and the first or second fixed mold are selectively opposed to each other for injection molding. When double-molding a molded product, there is a drawback that the support member must be moved vertically over a long distance. In other words, in order to make it possible to move the fixed mold according to the length of the molded product below or above the injection device, the height of the main body frame itself must be increased to accommodate the mounting plate that has been moved downward. Or you have to provide a lot of space above. For this reason, when the fixed mold for a long object is located within the main body frame, the molding machine itself becomes larger and heavier, and when the fixed mold is located above, the molding machine The installation space became large, and the factory space could not be used effectively. The present invention was invented to solve the above-mentioned conventional drawbacks, and its purpose is to easily modify existing molding machines to reduce the size and weight of the injection device while increasing its longevity. It is an object of the present invention to provide a double injection molding method capable of efficiently molding even large molded products.

[Means to solve the problem]

For this reason, the present invention provides a double injection molding method in which a second molded product made of the same or a different type of synthetic resin is integrally molded with a first molded product and the product is injection molded. Of the first and second movable molds that are attached at a predetermined interval in the lateral direction to a movable member that is supported so as to be movable in the lateral direction orthogonal to the direction, the first movable mold is After the mold and a single fixed mold are faced and clamped, a first injection device injects the constituent resin into the molding space between the first movable mold and the fixed mold to form a first molded product. is molded, and then when the first movable mold is released from the fixed mold, the movable member is moved so that the second movable mold faces the fixed mold holding the first molded product. After the mold is clamped, a second injection device injects synthetic resin into the molding space between the second movable mold and the fixed mold to integrally mold the second molded product with the first molded product. It is characterized by

[Action of the invention]

Since the present invention is configured as described above, as the movable member moves, the first movable mold is opposed to a single fixed mold and these are clamped, and then the first movable mold is clamped by the first injection device. A first molded product is molded by injecting synthetic resin into a molding space between one movable mold and a fixed mold. Next, after releasing the first movable mold from the fixed mold, the movable member is moved and the second movable mold is moved to the fixed mold holding the first molded product.
Clamp the movable molds facing each other. And these second
When the synthetic resin is injected by the second injection device into the molding space formed by the movable mold and the fixed mold, the second molded product is integrated with the first molded product. The product is molded by injection molding. Therefore, even when double-molding a long product, it is possible by improving an existing molding machine, and the molding machine can be made smaller and lighter.

【Example】

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view schematically showing an injection molding apparatus embodying a double injection molding method, and FIG. 2 is a perspective view showing a sliding mechanism of a movable mold. A pair of mounting plates 5 and 7 facing each other are provided at a predetermined interval in the longitudinal direction of the main body frame 3, and between the mounting plates 5 and 7 there are four guide shafts 9 whose axes are aligned with the main body frame 3. It is installed parallel to the longitudinal direction of the A movable platen 11 is supported on these guide shafts 9 so as to be movable in the axial direction. Further, a rod 13a of a mold clamping cylinder 13 attached to the main body frame 3 is fixed to the movable platen 11, and when the mold clamping cylinder 13 is operated, the movable platen 11
is reciprocated in the axial direction. A support frame 15 is attached to the movable platen 11, and a slide plate 17 as a movable member is supported on the support frame 15 so as to be movable in the lateral direction orthogonal to the mold clamping direction. The slide board 1
A rod 19a of the cylinder 19 attached to the support frame 15 is attached to 7, and the rod 19a of the cylinder 19 is attached to the support frame 15.
The first and second movable molds 2, which will be described later along with the operation of 9,
1 and 23 are moved so that they are located at the mechanical center of the main body frame 3. First and second movable molds 21 and 23 are detachably attached to the slide board 17 at a predetermined interval with respect to the moving direction of the slide board 17. A fixed mold 25 corresponding to the shape of the product 53 to be integrally molded is removably attached to the mounting plate 7 facing the movable plate 11. Further, an auxiliary frame 33 is attached to the side of the main body frame 3 corresponding to the mounting plate 7 so as to extend in a direction perpendicular to the longitudinal direction of the main body frame 3. A stand 35 is supported so as to be movable in a direction perpendicular to the longitudinal direction of the main body frame 3. The first
On the injection table 35, there is a first injection device 37 having a built-in injection screw (not shown) having an axis perpendicular to the injection screw of a second injection device 29, which will be described later. It is attached so as to coincide with the parting surface of the clamped fixed mold 25 and the first movable mold 21. Further, a rod (not shown) of a first cylinder 39 attached to the auxiliary frame 33 is connected to the first injection table 35, and as the first cylinder 39 operates, the first injection The device 37 is moved in a direction perpendicular to the axis of the guide shaft 9. A second injection table 27 is attached to the main body frame 3 corresponding to the side of the mounting plate 7 so as to be movable in the longitudinal direction of the main body frame 3. A second injection device 29 is installed which includes an injection screw (not shown) with a matching axis. A rod (not shown) of a second cylinder 31 attached to the main body frame 3 is connected to the second injection table 27, and as the second cylinder 31 operates, the second injection table 27 , thus the second injection device 29 is moved in the axial direction. Next, a double injection molding method using the injection molding machine 1 configured as described above will be explained with reference to FIGS. 3 and 4. In FIG. 3 showing the molding state of the first molded product 41, when the cylinder 19 is not in operation, the slide plate 17 is moved to the right as shown in FIG. Of the mold 21 and the second movable mold 23, the first movable mold 21 is moved to face the left side of the fixed mold 25. In this state, the mold clamping cylinder 13
When operated, the first movable mold 21 is clamped against the fixed mold 25. Next, the first movable mold 21 with the first injection table 35 clamped by the first cylinder 39 operated in this state
When the first injection table 35 is moved toward the fixed mold 25, the injection nozzle of the first injection device 37 provided on the first injection table 35 is moved toward the first movable mold 21 and the fixed mold 25. The contact surface is pressed against the contact surface. Next, in the above state, the first injection device 3
The molten synthetic resin from the injection nozzle 7 is applied to the parting surface of the first movable mold 21 and the fixed mold 25 via the sprue 43, and then to the parting surface between the first movable mold 21 and the fixed mold 25. When injected into the first molding space 45, the first molded product 41 is molded. When the first cylinder 39 is moved back after the above operation, the injection nozzle of the first injection device 37 is separated from the parting surface between the first movable mold 21 and the fixed mold 25 and returned to its original position. At the same time, when a predetermined curing time has elapsed, the first movable mold 21 is released from the fixed mold 25 by the return movement of the mold clamping cylinder 13. The first molded product 41 molded at this time is held within the fixed mold 25. . Next, in FIG. 4 showing the operation of integrally molding the second molded product onto the first molded product, the cylinder 19 is operated with the first molded product 41 held within the fixed mold 25. Then, the slide plate 17 is moved toward the left side as shown in FIG. 4, and the second movable mold 23 is opposed to the fixed mold 25. When the mold clamping cylinder 13 is operated in the above state, the first
The second movable mold 23 is clamped to the fixed mold 25 holding the molded product 41. At this time, the first molded product 41 is located in a second molding space 47 formed by the second movable mold 23 and the fixed mold 25. Then, the second injection table 2 is activated by the second cylinder 31 that operates.
7 is moved toward the back of the fixed mold 25, the second
The injection nozzle of the injection device 29 is connected to the sprue 4 of the fixed mold 25.
9 is pressed against. Then, in the above state, the second injection device 2
When the molten synthetic resin is injected into 47 from the injection nozzle 9, the second molded product 51 is integrally fused and molded to the first molded product 41, and a product 53 is molded. Note that when the product 53 is molded, the injection nozzle of the second injection device 29 is separated from the sprue 49 of the fixed mold 25 by the first cylinder 31 which is moved back, and a predetermined curing time is maintained. When the time has elapsed, the second movable mold 23 is moved from the fixed mold 25 by the mold clamping cylinder 13 that moves back.
is released from the mold. At this time, the integrally molded product 53 is held in the second movable mold 23, and when the movable platen 11 is moved back to a predetermined position, the ejecting mechanism built in the movable platen 11 ( (not shown) makes the second movable mold 23
The product 53 is taken out from the product 53. In this way, the method of this embodiment moves the slide plate 17 in the lateral direction perpendicular to the mold clamping direction by the mold clamping cylinder 13, and connects the first movable mold 21, the second movable mold 23, and the fixed mold 25. By selectively facing them, it is possible to integrally mold the product 53 consisting of the first molded product 41 and the second molded product 51, so even if the product 53 is a long product, it can be It can be integrally molded using an injection device, and the molding machine can be made smaller and lighter. In the above description, the first movable mold 21 and the second movable mold 23, which are separate bodies, are removably attached to the slide board 17 at a predetermined interval in the lateral direction, and the slide board 17 As the first movable mold 21 moves relative to the fixed mold 25,
A product 53 consisting of a first molded product 41 and a second molded product 51 is integrally molded by selectively opposing the second movable mold 23, but as shown in FIG. The first molded product 41 and the second molded product 5 are attached to the plate 17.
A single movable mold block 61 in which convex portions 61a and 61b are respectively formed according to the shape of the mold 1 is removably attached, and the convex portions 61 are attached to the fixed mold 25 by the operation of the cylinder 19.
The product 53 may be integrally molded with the convex portions 61a and 61b selectively facing each other.

【Effect of the invention】

Therefore, the present invention has developed a double injection molding method that can easily modify an existing molding machine to make the injection device smaller and lighter, while also efficiently molding long products. it is possible to provide

[Brief explanation of drawings]

Fig. 1 is a perspective view schematically showing an injection molding apparatus embodying the double injection molding method, Fig. 2 is a perspective view showing a sliding mechanism of a movable mold, and Fig. 3 is a molding state of the first molded product. FIG. 4 is an explanatory diagram showing the effect of integrally molding the second molded product onto the first molded product. FIG. 5 is an explanatory diagram showing a modified example for carrying out the method of the present invention. be. In the figure, 1 is an injection molding machine, 15 is a movable plate, 17 is a slide plate as a movable member, 19 is a cylinder 21 is a first movable mold, 23 is a second movable mold, 25 is a fixed mold, 29 37 is a first injection device, 37 is a second injection device, 41 is a first molded product, 51 is a second molded product, and 53 is a product.

Claims (1)

[Claims] 1. In a double injection molding method in which a second molded product made of the same or a different type of synthetic resin is integrally molded with a first molded product to injection mold the product, a movable platen Of the first and second movable molds that are attached at a predetermined interval in the lateral direction to a movable member that is supported so as to be movable in the lateral direction perpendicular to the mold clamping direction, the first movable mold is After the movable mold and a single fixed mold are faced and clamped, the constituent resin is injected into the molding space between the first movable mold and the fixed mold by the first injection device to form the first mold. A molded product is molded, and then, when the first movable mold is released from the fixed mold, the movable member is moved to place a second movable mold on the fixed mold that held the first molded product. After the molds are clamped facing each other, a second injection device injects synthetic resin into the molding space between the second movable mold and the fixed mold to integrate the second molded product into the first molded product. A double injection molding method characterized by molding. 2. The double injection molding method according to claim 1, wherein the movable member is provided with first and second movable molds separately provided at a predetermined interval in a lateral direction perpendicular to the mold clamping direction. 3. A movable mold block is attached to the movable member, in which a mold corresponding to the first molded product and molds corresponding to the first and second molded products are integrally formed at a predetermined interval. Item 1. Double injection molding method according to item 1.