JPH039869B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transfer molding method and apparatus. Transfer molding equipment inserts a plastic transfer film between the molds of an injection molding machine.
This is a device that transfers a pattern previously printed on a transfer film to a molded product at the same time as molding.

As a conventional transfer molding apparatus, there is one shown in FIGS. 1 and 2, for example.

This transfer molding device includes a fixed plate 11, a tie bar 1
2. Movable plate 13, fixed mold 14 attached to fixed plate 11, movable mold 1 attached to movable plate 13
5. Film supply attached to movable platen 13
It has a positioning device 16, an injection nozzle 17, etc. Note that the fixed mold 14 has three molds 14a and 14b.
and 14c, which are guided by the pin 18 and are movable in the axial direction of the pin 18. Film supply/positioning device 16
is a roll 20a rotated by a motor 19
It has a roll 20b pressed against it, a roll 22a rotated by a motor 21, and a roll 22b pressed against it, whereby the transfer film 24 is sequentially sent out from the coil 23. . The feeding length of the transfer film 24 can be controlled by controlling the operating time of the motor 19 using a timer;
This is done by a method such as reading the mark on the top with an optical sensor to determine the position. 1st
When the transfer film 24 is positioned as shown in the figure, the movable plate 13 moves from left to right in FIG. The transfer film 24 is first transferred to the fixed mold 1.
4, and then sandwiched between the mating surfaces of the fixed mold 14 and the movable mold 15. Further, as the movable platen 13 moves forward, the molds 14a, 14b, and 14c of the fixed mold 14 come into close contact with each other.
However, the transfer film 24 is not the same as the mold 1 of the fixed mold 14.
4a and then each mold 14a, 1 of the fixed mold 14
Until 4b and 14c are completely in contact with each other, the transfer film 24 is not firmly sandwiched between the fixed mold 14 and the movable mold 15.
They are simply held together by a force equivalent to the frictional force between the mold 14a and the pin 18. For this reason,
The transfer film 24 may be misaligned due to vibrations, wind pressure, etc. caused by the movement of the movable platen 13. In addition, the moving load on the movable platen was also increased. Furthermore, it is necessary to install a hydraulic cylinder for ejecting in a limited space on the fixed type side, which greatly limits the degree of freedom in designing the hydraulic cylinder. Furthermore, since the molded transfer film moves together with the positioning device attached to the movable platen when the mold is opened and closed, it was necessary to consider the interlocking with the film winding device provided on the fixed part side.

For this reason, it is conceivable to provide a film positioning device on the fixed mold side and guide the resin injected from the fixed mold side to the opposite side of the transfer film, but conventionally, a side gate was provided for this purpose and the transfer film I tried to bypass it. However, this method has the problem that the runners guiding the resin are long, resulting in a large amount of resin being wasted, and also has the disadvantage that the width of the mold becomes large.

The present invention was made by focusing on the above-mentioned problems in conventional transfer molding methods and devices, and involves making holes in the transfer film and sending resin from the fixed mold side to the movable mold side through the holes. This aims to solve the above problems.

Hereinafter, the present invention will be explained based on FIGS. 3 to 8 of the accompanying drawings showing embodiments thereof.

A first embodiment is shown in FIGS. 3-5. frame 30
A fixed platen 32 is fixed thereon, and a movable platen 34 facing the fixed platen 32 is guided by tie bars 36 and is movable in the horizontal direction. A movable mold 38 and a movable mold 42 guided by support pins 40 are attached to the movable platen 34 . The fixed platen 32 includes a film supply/positioning device 44.
A fixed mold 46 is provided, and a hole punching device 48, which will be described later, is provided within the fixed mold 46. Note that the mold constituted by the movable molds 38, 42 and the fixed mold 46 is a multi-cavity mold having a molding section 86 for molding four molded products at the same time. The film supply/positioning device 44 includes a coil 5 provided on a horizontally movable movable frame 50.
2, feed roll 54, guide roll 56, guide roll 58, dancer roll 60, and tension roll 6
The transfer film 64 unwound from the coil 52 is finally transferred to a winding device 66.
It is wound up. The injection nozzle 68 is connected to the fixed platen 32
The central part of the fixed mold 46 can be entered from the side.

A drilling device 4 arranged in the center of the fixed mold 46
8 is enlarged and shown in FIG. A blade 72 is rotatably supported in a recess 70 in the center of the fixed mold 46 using a pin 74 as a fulcrum. The blade 72 is approximately equally spaced 4 on the circumference.
It is located at a specific location. The blade 72 is the spring 7
6, it is normally accommodated in the recess 70 in the state shown by the imaginary line. The fixed mold 46 also has an axially movable intermediate nozzle 78.
is provided, with intermediate nozzle 78 normally in the position shown in phantom under the action of spring 80. The intermediate nozzle 78 has a sprue runner 82 extending therethrough in the axial direction. The injection nozzle 68 can come into contact with the right end of the sprue runner 82 in FIG. It is possible to contact the opening of the sprue runner 84 of the movable mold 42 when the movable mold 42 is moved. The sprue runner 84 of the movable mold 42 communicates with the molding section 86.

Next, the effect will be explained.

First, the transfer film 64 is positioned by the action of the film supply/positioning device 44, and then the movable platen 34 advances rightward in FIG. 3 to perform a mold closing operation. As a result, the transfer film 64 is sandwiched between the movable mold 42 and the fixed mold 46. After mold clamping, the injection nozzle 68
Move forward to the left in the figure and press the intermediate nozzle 78.
Therefore, the left end of the intermediate nozzle 78 in FIG. 5 pushes the blade 72, causing it to rotate about the pin 74 as a fulcrum. That is, the intermediate nozzle 78 and the blade 72 are
Each moves from a state shown by a virtual line to a state shown by a solid line. The transfer film 64 is cut by this rotation of the blade 72. The blade 72 is 4
Since the transfer film 64 is provided at
is cut into a cross shape. The intermediate nozzle 78 moves forward, pushing aside the cut transfer film 64, and comes into contact with the opening of the sprue runner 84.
In this state, resin is injected from the injection nozzle 68. The resin injected from the injection nozzle 68 passes through the sprue runners 82 and 84.
It passes between the movable mold 42 of the molding section 86 and the transfer film 64, and transfers the design on the transfer film 64 at the same time as molding. After molding, it is cooled and then the mold is opened. By opening the mold, the sprue in the sprue runner 82 of the intermediate nozzle 78 moves toward the movable mold 42 together with the sprue in the sprue runner 84. Simultaneously with the mold opening operation, the transfer film 64 is peeled off from the molded product 88. Furthermore, when the mold is opened, the movable mold 42 is pulled by a tensioning device such as a chain (not shown) and is separated from the movable mold 38. By doing so, the sprue 90 can be ejected by an ejector (not shown). The molded product 88 is also ejected by an ejection device (not shown). The transfer film 64 is fed by a predetermined amount by the dancer roll 60 moving to the lower end position shown by the imaginary line, and then being wound up by the tension roll 62 to the upper end position shown by the solid line. The formed transfer film 64 is wound up by a winding device 66. Due to the above, 1
Finish the molding cycle.

Next, a second embodiment shown in FIGS. 6, 7 and 8 will be described. This transfer molding device is provided with a hole punching device at a position before the molding film enters the mold. That is, as shown in FIG. 6, the drilling device 48' is provided on the movable frame 50. Note that the other configurations are the same as those shown in FIG. 3, so the same reference numerals are given and detailed explanations are omitted. The drilling device 48' is shown in an enlarged view in FIG. This hole punching device 48' is arranged to punch a hole in the transfer film 64 at a position one cycle before entering the forming section. The drilling device 48' includes a case 92, a receiving blade 94 attached to the case 92, and a pushing blade 96 that is movably supported within the case 92 and can be engaged with the inner diameter of the receiving blade 94.
The push blade 96 is driven by a motor 100 via a crank mechanism 98 to reciprocate.
As a result, a circular hole is formed in the transfer film 64. The cut piece 102 punched out by the pusher blade 96 is removed by a chute 104.
In order to make the perforation position accurate, the above-mentioned perforation is performed after the transfer film 64 has been positioned. Transfer film 64 with holes as shown in Figure 8
is shown positioned at the center of the fixed mold 46. In this case, the injection nozzle 68 directly contacts the convex portion 42a of the movable mold 42 passing through the hole in the transfer film 64 to inject the resin. It is clear that this embodiment also provides the same functions and effects as those of the first embodiment described above.

Note that, as shown in FIG. 8, the convex portion 42a is designed to be engaged with and guided by a bushing 106, but the bushing 106 is not necessarily necessary.
A gap may be provided between the fixed mold 46 and the convex portion 42a. Furthermore, the reason why the convex portion 42a is made to protrude toward the fixed mold 46 is to prevent resin spilled from the injection nozzle 68 from getting caught in the parting surface of the mold. The injection nozzle 68 may be a shut-off nozzle.

In the second embodiment, the transfer film 64 was formed with a circular hole, but the transfer film 64 was cut into a cross shape and an intermediate nozzle 78 shown in FIG. 5 was used as in the first embodiment. It's okay.

In addition, in the above two embodiments, the transfer film 6
Although a special hole-making device 48 is provided to make holes in 4, other means for making holes may be used, such as a method of piercing the transfer film 64 with an injection nozzle, or a method of piercing the transfer film 64 with the pressure of the injected resin. A method of piercing the film 64 or the like may be used.

Note that the present invention can be applied to a multi-cavity molded product without a pattern at the center of the mold or to a donut-shaped molded product.

As explained above, according to the present invention, the transfer molding method involves providing a hole in the transfer film unwound from the coil, and connecting the movable mold and the transfer film through the hole in the transfer film from the fixed mold side. Since the resin is injected between the holes, the transfer molding equipment that implements this method requires a punching device that makes holes at predetermined positions in the transfer film, and a film supply/positioning device that is installed on the fixed mold side. and an injection nozzle provided on the fixed mold side that can inject the resin through the hole of the positioned transfer film, so there is less disturbance to the film supply/positioning device and the positioning accuracy can be improved. Also, compared to the conventional side gate method,
The runners are short and there is less waste of resin. In addition, since the film supply/positioning device is fixed,
Interlocking with the winding device is easily performed. Furthermore, the ejector cylinder of a normal horizontal injection machine can be used as an ejection device for molded products.
The degree of freedom in setting ejection timing and ejection force increases.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional transfer molding device, FIG. 2 is a sectional view taken along the - line of the transfer molding device shown in FIG. 1, FIG. 3 is a diagram showing a transfer molding device according to the present invention, and FIG. is the − of the transfer molding apparatus shown in Fig. 3.
5 is an enlarged sectional view of the central part of the mold of the transfer molding apparatus shown in FIG. 3; FIG. 6 is a sectional view of the transfer molding apparatus according to the second embodiment of the present invention; FIG. 7 is an enlarged view of the hole punching device of the transfer molding apparatus shown in FIG. 6, and FIG. 8 is an enlarged view of the central part of the mold of the transfer molding apparatus shown in FIG. 30...Frame, 32...Fixed plate, 34...
Movable plate, 36... Tie bar, 38... Movable type, 40
...Support pin, 42...Movable type, 44...Film supply/positioning device, 46...Fixed type, 4
8...Drilling device, 50...Movable frame, 52
... Coil, 54 ... Feed roll, 56 ... Guide roll, 58 ... Guide roll, 60 ... Dancer roll, 62 ... Tension roll, 64 ... Transfer film, 66 ... Winding device, 68 ... ...Injection nozzle, 70...Recess, 72...Blade, 74...Pin,
76... Spring, 78... Intermediate nozzle, 80... Spring, 82... Sprue runner, 84... Sprue runner, 86... Molded part, 88... Molded product,
90... Sprue, 92... Case, 94... Receiving blade, 96... Pushing blade, 98... Crank mechanism, 10
0...Motor, 102...Cut piece, 104...Shoot, 106...Button.

Claims (1)

[Claims] 1. In a transfer molding method in which a transfer film is sandwiched between a fixed mold and a movable mold and the design on the transfer film is transferred to a molded product at the same time as injection molding, a transfer film unwound from a coil is used. A transfer molding method characterized in that a hole is provided in the film, and resin is injected from the fixed mold side through the hole in the transfer film between a movable mold of a mold forming section and the transfer film. 2. In a transfer molding device that inserts a transfer film between a fixed mold and a movable mold and transfers the design on the transfer film to a molded product at the same time as injection molding, a hole punching device that makes holes at predetermined positions in the transfer film; A transfer molding apparatus comprising: a film supply/positioning device provided on the fixed mold side; and an injection nozzle provided on the fixed mold side capable of injecting resin through holes in the positioned transfer film. 3. The transfer molding device according to claim 2, wherein the hole punching device is arranged within the fixed mold. 4. The transfer molding apparatus according to claim 2, wherein the perforation device is provided at a position where it can make holes in the transfer film before it is sent between the fixed mold and the movable mold.