JPH0434004Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The invention consists of feeding a continuous film with a pattern printed at a predetermined pitch into the female mold cavity opening,
The present invention relates to an injection molding device for injecting molten resin into a cavity from an injection device on the female mold side to produce a three-dimensional molded product with a pattern attached.

[Conventional technology]

In general, a device for producing a three-dimensional molded product by feeding a continuous film with a pattern printed at a predetermined pitch one after another into the cavity opening of a female mold and injecting molten resin from an injection device installed on the female mold side. The type that heats the continuous film in front of the mold and feeds the heated part onto the cavity, or the type that heats the continuous film by adsorbing it with a movable heating plate in front of the female mold, and then transfers the heated part directly to the heating plate. There is a type in which injection molding is performed by moving a continuous film to the cavity opening, feeding the continuous film onto the cavity, and spraying the heated pattern onto the bottom of the cavity via a heating plate.

[Problem that the invention attempts to solve]

In the former case, since the heated and softened film is conveyed onto the cavity, accurate positioning on the cavity is difficult. In addition, in the latter case, after the film is adsorbed and heated above the female mold,
Since the film is fed onto the cavity while being heated, it requires a relatively large number of mechanical operations and is complicated, and since the film is not directly aligned on the cavity, the alignment accuracy is poor.
Therefore, an object of the present invention is to provide a device with a relatively simple structure and accurate alignment.

[Means for solving problems]

In order to solve this problem, the present invention involves feeding a continuous film with patterns formed at a predetermined pitch into corresponding positions of a cavity formed in a female mold, closing the cavity with a male mold, and injecting molten resin. In the injection molding apparatus for producing a three-dimensional molded product having a pattern, the injection molding apparatus includes a film support device provided to support the continuous film, and a film support device located above the female mold, a feed roller for feeding the continuous film supported by the support device into the opening of the cavity; a retraction roller provided below the female die for drawing the continuous film downward; and a constant tension for applying a certain tension to the continuous film. a tension roller for detecting marks formed on the continuous film at predetermined pitches, and a sensor for aligning the pattern of the continuous film with the cavity opening and stopping the continuous film;
It is characterized by comprising a movable heating plate that reciprocates between the cavity opening and a standby position above the cavity opening and heats the continuous film hanging down along the cavity opening at the cavity opening position.

[Effect]

Films are fed into the cavity opening of the female mold one after another from a film support device slidably provided on the female mold, and marks formed on the film are detected by a sensor to stop the film feeding roller and the retraction roller. . At this time, the tension roller acts to position the film at the cavity opening with a constant tension. Thereafter, the heating plate is moved to the opening of the cavity, heated by adsorption, and while the cavity is evacuated, the heated film is force-fed to the bottom of the cavity by compressed air.

In this way, the film pattern can be accurately aligned with the cavity opening, and since the film is heated, the pattern can be accurately transferred to the uneven three-dimensional molded product.

[Example of idea]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In the present invention, as shown in FIG. 1, a molded article W mainly having an uneven pattern P on its surface is produced by injection molding of molten resin.

The injection molding apparatus M of the present invention is shown in FIGS. 3 and 4.
As shown in the figure, it has a female mold 2 supported by a movable platen 1, in which a molding cavity C is formed and air communication holes 3, 3 for vacuum extraction are formed. The air communication hole 3 is connected to a vacuum source (not shown). Moreover, the air communication hole 3 is the sixth
As shown in the figure, the opening may be made in the front step of the female mold 2.

A film support device 4 for supporting a film roll 4 is slidably provided on the upper surface of the movable platen 1, and the continuous film F sent out from this device 4 passes through the front surface of the female cavity opening. A film processing device 6 hanging down and provided below the female mold 2
drawn in by.

On the other hand, a male die 8 fixed to a stationary plate 7 is located corresponding to the female die 2, and a nozzle 9 as an injection device is installed inside the stationary plate 7 and the male die 8.

A heating plate 10 is installed at the upper center of the female and male molds 2 and 8.
is provided, and this heating plate 10 is connected to a drive cylinder 11
The movable platen 1 is held vertically movably and guided by guide rails 12, 12 provided on the sides of the moving path of the movable platen 1.

The female die 2 is supported by a support plate 13 attached to the upper part of the movable plate 1, and the film support device 5
are holding plates 14, 1 provided at intervals on the movable plate 1;
4, and the lower part of this holding plate 14 is provided on slide parts 1a, 1a formed on the movable plate 1 so as to be slidable in the moving direction of the movable plate 1. As a result, the continuous film F is adjusted to hang down at a predetermined position on the front surface of the cavity opening of the female mold 2. A feed roller 16 rotated by a pulse motor 15 is provided in front of the holding plate 14, and a presser roller 17 is provided opposite the feed roller. Arms 18,1 from the front of this holding plate 14
8 protrudes, and a continuous film F is attached to the front end of this arm 18.
A guide roller 19 for guiding is supported.

A pattern P is printed on the film F at a predetermined pitch as shown in FIG. 2, and positioning marks m, m, . It is detected by optical sensors 20, 20 provided on both sides of the front surface. This optical sensor 20 is configured so that its mounting position can be adjusted.

The film processing device 6 includes a vertical plate 22 supported by an arm 21 projecting forward from the lower part of the movable plate 1;
22, and between this vertical plate 22, two pinch rollers 23, 23 from above, a tension roller 24,
A pull-in roller 25a rotationally driven by a pulse motor 26 and a press roller 25b that cooperates with the pull-in roller 25a are supported. The tension roller 24 is used to always apply a constant tension to the continuous film F, and the tension roller 24 is arranged so that its shafts 24a, 24a move along diagonal slits 27, 27, which serve as guide sections. It's getting old.

The heating plate 10 includes a support frame 30 that is guided vertically along the guide rail 12, and a heating plate 31 is mounted on the support frame 30 in a direction perpendicular to the moving direction of the heating plate 10 (horizontal direction). movably supported. Cylinders 32, 32 as driving devices are provided on the side surfaces of the support frame 30 and the heating plate 31, and the expansion and contraction of the cylinders 32 causes the heating plate 31 to move in the horizontal direction.

The heating plate 31 has air holes 31a, 31a,...
..., 31a are formed, and air holes 3 are formed on the Teflon-treated suction surface S on the front surface of the heating plate 31.
1a is formed with a pitch of 5 to 20 mm, and its diameter is
0.3 to 0.7 mm is preferred. The heating plate is a hot plate heater, a sintered metal heater, or a heat-resistant composite resin heater. The air hole 31a is connected to a vacuum source and a compressed air source (not shown) via a switching valve, and when the film F is to be adsorbed to the suction surface S, it is connected to the vacuum source, and the film F is adsorbed to the suction surface S immediately before injection. When the film F is forced into the cavity, it is connected to a compressed air source.

Next, the operation of this device will be explained.

In FIG. 3, when the molded product W is taken out, the feed roller 16 and the pull-in roller 25a rotate to advance the film F by one pitch. When the film F is lowered and the sensor 20 detects the mark m (FIG. 2) on the film, the sensor 20 activates the pulse motor 1 of the feed roller 16 and the retraction roller 25a.
5 and 26 are stopped. When the film F is being fed, the tension roller 24 is in a slightly elevated position from the position shown in FIG. Give a predetermined tension to. The mounting position of the sensor 20 is adjustable, and the position is such that when a predetermined tension is applied to the film F by the tension roller 24, the pattern P is at a predetermined position in the cavity opening. is set to In this way, the pattern is accurately positioned with respect to the cavity C by the action of the tension roller 24 and the sensor 20. Note that the sensor 20 is provided on the front surface of the female mold 2, that is, it directly detects the mark m for the pattern P corresponding to the cavity C. Positioning accuracy is improved compared to the conventional one.

Furthermore, since the tension roller 24 is restricted in its movement by the slit 27, it can be used even if the film F is fed at a long pitch. That is, conventionally, the tension roller 102 is
03 and pinion 102 mechanism to move it up and down, in this case the tension roller 1
00 moves up and down within a range of distance l, and if the pitch of the picture is made longer than l, it becomes unusable, but the structure of the present invention eliminates this disadvantage.

When the film F stops at the proper position relative to the cavity C, the heating plate 10 is moved to the drive cylinder 1.
1, the film F is independently lowered from the standby position shown in FIG. 3, and then lowered to a position opposite the cavity C and stopped as shown in FIG. After that, the cylinder 32 is extended and the heating plate 3
Press 1 onto the front of the female mold. At this time, the air holes 31a are communicated with a vacuum source to attract the film F to the suction surface S of the heating plate 31. Film F
After being adsorbed and heated for a short time, the switching valve is switched to connect the air hole 31a to a compressed air source, and the heated film is fed under pressure to the bottom of the cavity C to preform a patterned film. At this time, the cavity C of the female mold 2 is evacuated through the air communication hole 3.

After that, the heating platen 10 is raised, the movable platen 1 is further moved in the direction of the male mold 8, the male mold 8 is engaged with the cavity C, and the molten resin (ABS, PS, AS, MMA ,PC,PVC,PP,
A molded product W is made by injecting thermoplastic resin such as PE. After the molded product W is extruded by the cavity C, the above-described operation is repeated.

[Effects of the Invention] According to the present invention, since the sensor for detecting the mark on the film is provided on the female die, the pattern on the film can be directly aligned with the cavity on the female die. Furthermore, after aligning the pattern with the cavity, the movable heating plate is lowered from an upper standby position to the cavity independently of the film, so that no misalignment occurs between the pattern and the cavity during heating. Furthermore, a predetermined tension can be applied to the film using a tension roller. In this way, the pattern on the continuous film can be accurately stopped at a predetermined position in the cavity opening, and since the film F is heated at the cavity opening, operations such as moving the softened film are not required, and the pattern can be accurately maintained. This has the effect that even a molded product with irregularities attached to a certain position can be manufactured.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the molded product, Fig. 2 is a front view of the continuous film, Fig. 3 is a schematic configuration diagram of the injection molding apparatus of the present invention, Fig. 4 is a front view of the injection molding apparatus, and Fig. 5 6 is a state diagram when the cavity is closed with a heating plate, FIG. 6 is a diagram of another embodiment of a female type, and FIG. 7 is a diagram of a conventional tension roller. DESCRIPTION OF SYMBOLS 1...Moving plate, 2...Female mold, 5...Film support device, 6...Film processing device, 8...Male mold,
10... Heating plate, 20... Sensor, 24... Tension roller, 25a... Retraction roller.

Claims (1)

[Claims for Utility Model Registration] 1. At the corresponding position of the cavity formed in the female mold,
In an injection molding apparatus for producing a three-dimensional molded product having a pattern by feeding a continuous film having a pattern formed at a predetermined pitch, closing the cavity with a male mold, and injecting molten resin, the injection molding device a film support device provided to support the film; a feed roller located above the female mold for feeding the continuous film supported by the film support device into the opening of the cavity; and a feed roller located below the female mold. a tension roller provided between the feeding roller and the drawing roller to apply a certain tension to the continuous film; and a tension roller provided in the female die to apply a certain tension to the continuous film. a sensor that detects marks formed at predetermined pitches on the continuous film and aligns the pattern of the continuous film with the cavity opening and stops the continuous film; and a sensor that aligns the pattern of the continuous film with the cavity opening and then stops the continuous film; and a movable heating plate that descends independently from the continuous film from an upper standby position to the cavity opening and heats the continuous film hanging down along the cavity opening at the cavity opening position. An injection molding device characterized by: 2. The injection molding apparatus according to claim 1, wherein the film support device is supported on the upper surface of a female movable plate so as to be slidable along the direction of movement thereof. 3. The injection molding apparatus according to claim 1, wherein the tension roller is movable along a guide portion extending diagonally over a short distance. 4. The heating plate includes a support frame guided along a guide rail, a heating plate supported movably in a direction perpendicular to the moving direction of the heating plate with respect to the support frame, and a drive for moving the heating plate. an air hole is formed in the heating plate for sucking the continuous film and spraying the heated continuous film onto the bottom surface of the cavity;
The injection molding apparatus according to claim 1, wherein the air hole is selectively connected to a vacuum source and a compressed air source. 5. The injection molding apparatus according to claim 4, wherein the front surface of the heating plate of the heating plate is treated with Teflon.