JPH0663989A - Plural material injection molding machine - Google Patents

Abstract

PURPOSE:To mold a second molded piece without removing a sprue runner after molding a first molded piece and opening the mold. CONSTITUTION:The plural material injection molding machine comprises a plurality of heating cylinders arranged in parallel, a stationary platen 61, and a movable platen 62. A stationary mold 63 is mounted at the platen 61, and a sprue is provided at a position of the mold 63 corresponding to the cylinder. A movable mold 64 is movably arranged at the platen 62, and a movable mold sliding unit 65 slides the mold 64 to molding positions of the cylinders. Positioning means for positioning the mold 64 is provided at molding position, and sprues are corresponded to the different positions on the mold 64. The mold 63 has a lightening hole 79 for containing a sprue runner 78 formed at the other molding position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-material injection molding machine.

[0002]

2. Description of the Related Art Conventionally, there are at least two heating cylinders, and a plurality of materials (for example, 2 materials) or a plurality of colors (for example, 2 materials)
In an injection molding machine (hereinafter, referred to as "multi-material injection molding machine") for molding with color resin, the heating cylinder is arranged on the fixed platen side or on the upper surface or side surface of the mold. For example, the molten resin is injected.

In a multi-material injection molding machine in which the heating cylinder is arranged on the upper surface or the side surface of the mold to inject resin, it is difficult to operate the molded product take-out machine, and the cost is high. In addition to increasing the height, especially in the case of disposing on the side surface of the mold, the width of the multi-material injection molding machine becomes wide and the occupied space becomes large. Therefore, the heating cylinder is usually arranged on the fixed platen side. In this case, the multi-material injection molding machine includes a reversing type for reversing the mold, a core back type for retracting a part of the core, and a slide type for sliding one mold.

FIG. 2 is a first process diagram of a conventional reversal type multiple material injection molding machine, FIG. 3 is a second process diagram of a conventional reversal type multiple material injection molding machine, and FIG. 4 is a conventional reversal type multiple material injection molding machine. FIG. 5 is a third process diagram in the material injection molding machine, and FIG. 5 is a fourth process diagram in the conventional reversal type multiple material injection molding machine. In FIG. 2, 11 is a fixed platen, 12 is a movable platen which is arranged so as to face the fixed platen 11 and is moved back and forth by a mold opening / closing device (not shown), 13 is a fixed mold attached to the fixed platen 11, 14 Is a movable mold which is disposed so as to face the fixed mold 13 and is attached to the movable platen 12 via the reversing device 15.

Reference numeral 18 is a first heating cylinder for melting the resin of the first material, and 19 is a second heating cylinder for melting the resin of the second material. The first material resin and the second material resin are different in type or color from each other and are injected from the first injection nozzle 20 and the second injection nozzle 21, respectively, and the fixed mold 13 and the movable mold 14 are injected. Is filled in the cavity formed by.

In this case, on the side of the first heating cylinder 18, the resin of the first material injected from the first injection nozzle 20 is filled in the cavity to form the first molded product portion 25. On the other hand, on the side of the second heating cylinder 19, the second resin injected from the second injection nozzle 21 is filled in the cavity, and the second resin is formed on the surface of the first molded product portion 25 molded by the previous shot. The molded part 26 is molded.

Subsequently, the mold is opened as shown in FIG. 3, and the sprue / runner portion 28 of the first molded product portion 25 is removed on the first heating cylinder 18 side. On the other hand, on the second heating cylinder 19 side, a molded product 27 including the first molded product portion 25 and the second molded product portion 26 is projected. Next, as shown in FIG.
It is reversed by 5, and the first molded product portion 25 moves from the first heating cylinder 18 side to the second heating cylinder 19 side.

Then, as shown in FIG. 5, the mold is closed and the mold is clamped, and the first heating cylinder 18 is provided with the first heating cylinder 18 side.
The first resin injected from the injection nozzle 20 is filled in the cavity to form the first molded product portion 25. on the other hand,
On the second heating cylinder 19 side, the second injection nozzle 2
The second resin injected from No. 1 is filled in the cavity, and the second molded product part 26 is molded on the surface of the first molded product part 25 molded in the previous shot.

The sprue bush on the side of the second heating cylinder 19 is a sprue / runner portion 28 of the first molded product portion 25.
However, since the sprue / runner portion 28 has been removed from the first molded product portion 25 at this point, it does not get in the way. FIG. 6 is a first process diagram of a conventional slide-type multi-material injection molding machine, FIG. 7 is a second process diagram of a conventional slide-type multi-material injection molding machine, and FIG. 8 is a first process diagram of a conventional slide-type multi-material injection molding machine. FIG. 9 is a fourth process drawing of a conventional slide-type multi-material injection molding machine.

In FIG. 6, 31 is a fixed platen, and 32 is a fixed platen.
Is a movable platen 33, which is arranged so as to face the fixed platen 31 and is moved back and forth by a mold opening / closing device (not shown).
Is a fixed mold attached to the fixed platen 31, 3
4 is a movable mold which is disposed so as to face the fixed mold 33 and is attached to the movable platen 32, and 35 is the movable mold 34.
It is a movable mold slide device for sliding.

Reference numeral 38 is a first heating cylinder for melting the resin of the first material, and 39 is a second heating cylinder for melting the resin of the second material. The resin of the first material and the resin of the second material are different in type or color from each other, and are respectively injected from the first injection nozzle 40 and the second injection nozzle 41, and the fixed mold 33 and the movable mold 34. Filled in the cavity formed by.

In this case, on the side of the first heating cylinder 38, the resin of the first material injected from the first injection nozzle 40 is filled in the cavity to form the first molded product portion 45. Subsequently, the mold is opened, and the movable mold 34 is slid to the second heating cylinder 39 side by the movable mold slide device 35 as shown in FIG. 7. At this time, the sprue / runner portion 48 of the first molded product portion 45 is left as it is on the first heating cylinder 38 side.

Next, as shown in FIG. 8, the mold is closed and clamped, the second resin injected from the second injection nozzle 41 is filled into the cavity, and the resin is molded by the previous shot. The second molded product portion 46 is molded on the surface of the first molded product portion 45. Then, the mold is opened as shown in FIG. 9, the molded product 47 is projected from the movable mold 34, and the sprue runner portion 48 is projected from the fixed mold 33.

[0014]

However, in the conventional multi-material injection molding machine, in the case of the reversal type multi-material injection molding machine, the sprue / runner section 28 is formed after the first molded product section 25 is molded. Since it has to be removed, the work is troublesome and the injection molding cycle becomes long.

Further, in the case of a slide type multi-material injection molding machine, since the sprue / runner portion 48 is formed in the fixed mold 33, both injection nozzles 40 and 41 must be avoided to form a cavity. Since it is necessary to provide a protrusion on the fixed mold 33 side, the runner becomes long, and the resin may be filled in the cavity while solidifying in the runner.

Therefore, the sprue on the second heating cylinder 19, 39 side is made thicker than that on the first heating cylinder 18, 38 side, and the sprue / runner portions 28, 48 of the first molded product portions 25, 45 and the second heating portion are heated. There is provided one in which an annular space is formed between the sprues on the cylinders 19 and 39 side and the resin is supplied through the annular space. FIG. 10 is a perspective view of a sprue in a conventional multi-material injection molding machine.

In the figure, 51 is a sprue of the first resin, 52 is a runner of the first resin, 53 is a sprue of the second resin, and 54 is a runner of the second resin. Since the second resin sprue 53 is formed thicker than the first resin sprue 51, the first molded product parts 25, 45 are formed.
A resin flow path for the second resin is formed around the sprue / runner portions 28 and 48 (FIGS. 3 and 9).

Therefore, the sprue / runner portions 28 and 48 do not interfere with the molding of the second molded product portions 26 and 46. However, in this case, since the sprue 53 becomes thick, the cooling time becomes long when the thermal conductivity of the first resin is poor. The present invention solves the problems of the conventional multi-material injection molding machine, and after molding the first molded product part and opening the mold, the second molded product part is formed without removing the sprue / runner part. It is an object of the present invention to provide a multi-material injection molding machine that is capable of molding, does not need to provide a protruding portion on the fixed mold side, and does not lengthen the cooling time.

[0019]

Therefore, in the multi-material injection molding machine of the present invention, a plurality of heating cylinders arranged in parallel, a fixed platen, and the fixed platen are arranged so as to face each other. A movable platen is provided. A fixed die is attached to the fixed platen, and a sprue is provided at a position of the fixed die corresponding to the heating cylinder. A movable die is movably arranged on the movable platen, and a movable die slide device slides the movable die to a molding position by the heating cylinders.

Positioning means for positioning the movable mold at each molding position is provided, and the sprues are associated with different positions on the movable mold. Further, the fixed mold has a waste hole for accommodating the sprue runner portion formed at another molding position.

[0021]

According to the present invention, as described above, a plurality of material injection molding machines are provided with a plurality of heating cylinders arranged in parallel, and each heating cylinder molds a plurality of materials or resins of a plurality of colors. A fixed platen and a movable platen disposed so as to face the fixed platen are provided, and a mold opening / closing device performs mold closing, mold clamping, and mold opening.

A fixed mold is attached to the fixed platen, and a sprue is provided at a position of the fixed mold corresponding to the heating cylinder. A movable die is movably arranged on the movable platen, and a movable die slide device slides the movable die to a molding position by the heating cylinders. Therefore, the movable mold slide device slides the movable mold to each molding position, injects the resin from the heating cylinder corresponding to each molding position, and molds each resin.

Positioning means for positioning the movable mold at each molding position are provided so that the sprues are associated with different positions on the movable mold. Therefore, the sprue / runner portions are formed at different positions each time molding is performed at each molding position. In addition, the fixed mold,
A drain hole is provided to accommodate a sprue runner portion formed at another molding position. Since the sprue / runner portions formed each time molding is performed at each molding position are housed in the waste holes, they do not interfere with each shot.

[0024]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a partial plan view of a multi-material injection molding machine showing an embodiment of the present invention, and FIG. 11 is a positional relationship diagram of a movable mold and an injection nozzle in the multi-material injection molding machine showing an embodiment of the present invention.

In FIG. 1, 61 is a fixed platen and 62
Is a movable platen 63 which is disposed so as to face the fixed platen 61 and is moved back and forth by a mold opening / closing device (not shown).
Is a fixed mold attached to the fixed platen 61, 6
Reference numeral 4 denotes a movable mold which is disposed so as to face the fixed mold 63 and is attached to the movable platen 62 via a movable mold slide device 65. In this case, the movable mold 64 is placed at a position before the molding of the first resin is completed and the molding of the second resin is started. The movable mold slide device 65 includes a rodless cylinder 81 that slides the movable mold 64 left and right, and a slide guide 82 that guides the movable platen 62.

Reference numeral 68 is a first heating cylinder for melting the resin of the first material, and 69 is a second heating cylinder for melting the resin of the second material. The resin of the first material and the resin of the second material are different in type or color from each other, and are injected from the first injection nozzle 70 and the second injection nozzle 71, respectively, and the fixed mold 63 and the movable mold 64. Filled in the cavity formed by.

In this case, on the side of the first heating cylinder 68, the resin of the first material injected from the first injection nozzle 70 is filled in the cavity to mold the first molded product portion. Subsequently, the mold is opened, and the movable mold 64 is slid to the second heating cylinder 69 side by the movable mold slide device 65. At this time, the sprue / runner portion 78 of the first molded product portion moves to the second heating cylinder 69 side together with the movable mold 64.

Next, the mold is closed and the mold is clamped. At this time, the sprue / runner portion 78 is housed in the waste hole 79 formed in the fixed mold 63. Then, the second resin injected from the second injection nozzle 71 is filled in the cavity to form the second molded product portion on the surface of the first molded product portion. Here, the first heating cylinder 68 and the second heating cylinder 69 are arranged in parallel, and the pitch L ₁ thereof is set to the same value as the sliding amount of the movable mold 64. And
The movable mold 64 is guided by the slide guide 82 and is suspended by the rodless cylinder 81 to move. In this case, the slide of the movable mold 64 is restricted by the stoppers 83 attached to the left and right ends of the injection molding machine frame.

Further, adjustment stoppers 84 are mounted as positioning means for positioning the movable mold 64 at positions on both ends of the movable mold 64 facing the stoppers 83, and the movable mold 64 is moved to the left and right. It is adapted to come into contact with and separate from the stopper 83 as it slides. In this case, the thickness of the adjusting stopper 84 is set to L ₂ .

Therefore, when the movable die 64 is slid to bring the adjusting stopper 84 into contact with the stopper 83 on the first heating cylinder 68 side, the center of the movable die 64 is the first.
From the center point A of the heating cylinder 68 to the second heating cylinder 6
It shifts to the 9 side by a distance L ₂ . Further, when the movable die 64 is moved to bring the adjustment stopper 84 into contact with the stopper 83 on the second heating cylinder 69 side, the center of the movable die 64 is first from the point B of the center of the second heating cylinder 69. It shifts to the heating cylinder 68 side by a distance L ₂ .

The sprue / runner portion 78 formed at the same time when the first molded portion is molded on the side of the first heating cylinder 68 remains at the position corresponding to the point A and remains on the side of the second heating cylinder 69 as it is. It moves and is accommodated in the waste hole 79. Since the waste hole 79 is formed at the point C corresponding to the point A, the sprue runner portion 78 is housed in the waste hole 79, and it is not necessary to remove the sprue runner portion 78.

Next, the runner / gate portion for molding the second molded product portion without removing the runner at the time of molding the first molded product portion will be described. FIG. 12 is an enlarged view of a gate portion in a multi-material injection molding machine showing an embodiment of the present invention. In the figure, 86 is a first molded product part molded with the first resin, 87 is a second molded product part molded with the second resin, 89 is a gate of the first resin, and 90 is 1. This is a resin runner.

The sprue runner portion 78 (FIG. 1) is formed separately when molding the first resin and when molding the second resin. Therefore, the first resin gate 89
If the or runner 90 is formed only on the movable mold 64 side, when the second resin is filled, the recesses of the gate 89 and the runner 90 do not exist on the movable side. Therefore, the resin of the second material can be filled without being disturbed by the runner 90 of the resin of the first material. Further, the gate 89 made of the first resin and the second molded product portion 87 made of the second resin are not easily joined to each other. Therefore, after molding the second molded part 87,
It is possible to easily separate the gate 89 and the runner 90.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention, and these are not excluded from the scope of the present invention.

[0035]

As described in detail above, according to the present invention, a plurality of heating cylinders are arranged in parallel in a multi-material injection molding machine, and a plurality of materials or a resin of a plurality of colors are used by each heating cylinder. Molding is performed. A fixed platen and a movable platen are provided, a fixed die is attached to the fixed platen, and a sprue is provided at a position of the fixed die corresponding to the heating cylinder. A movable die is movably arranged on the movable platen, and a movable die slide device slides the movable die to a molding position by the heating cylinders.

Therefore, the movable mold slide device moves the movable mold to each molding position and injects the resin from the heating cylinder corresponding to each molding position to mold each resin.
Positioning means for positioning the movable mold at each molding position is provided, and the sprues are associated with different positions on the movable mold. Therefore, the sprue / runner portions are formed at different positions each time molding is performed at each molding position.

Further, the fixed mold is provided with a waste hole for accommodating the sprue runner portion formed at another molding position. Since the sprue / runner portions formed each time molding is performed at each molding position are housed in the waste holes, they do not interfere with each shot. And
It is not necessary to remove the sprue runner portion for each molding at each molding position, and the injection molding cycle can be shortened. Further, since the sprue / runner portion can be projected when the molded product is projected, it is possible to prevent scattering of resin pieces, resin powder, and the like. Further, the position of the gate can be selected according to the shapes of the molded product part made of the first resin and the molded product part made of the second resin.

[Brief description of drawings]

FIG. 1 is a partial plan view of a multi-material injection molding machine showing an embodiment of the present invention.

FIG. 2 is a first process diagram in a conventional reversal type multiple material injection molding machine.

FIG. 3 is a second process diagram in a conventional reversal type multiple material injection molding machine.

FIG. 4 is a third process diagram in a conventional reversal type multiple material injection molding machine.

FIG. 5 is a fourth process diagram in a conventional reversal type multiple material injection molding machine.

FIG. 6 is a first process diagram in a conventional slide-type multi-material injection molding machine.

FIG. 7 is a second process diagram of a conventional slide-type multi-material injection molding machine.

FIG. 8 is a third process diagram in the conventional slide-type multi-material injection molding machine.

FIG. 9 is a fourth process diagram of a conventional slide-type multi-material injection molding machine.

FIG. 10 is a perspective view of a sprue in a conventional multi-material injection molding machine.

FIG. 11 is a positional relationship diagram of a movable mold and an injection nozzle in a multi-material injection molding machine showing an embodiment of the present invention.

FIG. 12 is an enlarged view of a gate portion in the multi-material injection molding machine showing the embodiment of the present invention.

[Explanation of symbols]

 61 Fixed Platen 62 Movable Platen 63 Fixed Die 64 Movable Die 65 Movable Die Sliding Device 68 First Heating Cylinder 69 Second Heating Cylinder 78 Sprue / Runner 79 Drain Hole 84 Adjustment Stopper

Claims (1)

[Claims] 1. A plurality of heating cylinders arranged in parallel, (b) a fixed platen, (c) a movable platen opposed to the fixed platen, and (d) the above. A fixed mold attached to a fixed platen and provided with a sprue at a position corresponding to each heating cylinder; and (e) a movable mold movably arranged on the movable platen,
(F) A movable mold slide device that slides the movable mold to a molding position by the heating cylinders, and (g) positions the movable mold at each molding position, and positions the movable mold at different positions on the movable mold. (H) The fixed mold has a positioning means for associating each sprue, and (h) the fixed mold is provided with a waste hole for accommodating the sprue runner portion formed at another molding position. Molding machine.