JPH0452034Y2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> The present invention relates to a blow molding device, and more particularly to a blow molding device that laminates a film on the outer peripheral surface of a parison simultaneously with blow molding.

<<Prior Art>> As blow molding in which a film is laminated on the outer circumferential surface of a parison simultaneously with blow molding, for example, the method disclosed in Japanese Patent Application Laid-open No. 89025/1989 is known.

In this way, when laminating a film on the outer circumference of the parison at the same time as blow molding, it is necessary to set or attach the film to the outer circumference of the parison in advance.

<<Problem to be solved by the invention>> In the blow molding apparatus disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 61-89025, when the parison and film are sandwiched between the molds, the film completely contacts the parison. As a result, there are parts of the film to which the heat of the parison is not sufficiently transferred, and there is a problem that the film parts are torn when blow molding is performed by blowing pressurized gas into the film.

Therefore, the edge of the film is pressed against a predetermined part of the outer peripheral surface of the parison, and the film is wound around the outer peripheral surface of the parison by rotating the parison, so that the entire surface of the film is in contact with the parison. After ensuring sufficient ductility of the film, it is conceivable that the film be sandwiched between molds and blow molded.

However, in this case, the parison is tilted due to the pressing of the film against the outer peripheral surface of the parison and the restraint of the film when the parison is rotated.
There is a problem in that the wrapping work cannot be performed as desired.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a blow molding apparatus that can prevent the parison from tilting when the film is wound around the parison, and improve the winding operation.

<Means for Solving the Problems> In the present invention, in a molded product in which a film is laminated on the outer peripheral surface of a parison as described above,
We focused on the fact that most of the parisons have a flat shape, and that a pair of expander pins are generally used to preform this flat shape.We used these expander pins to prevent the parison from tilting. It is something to do. That is, in the blow molding apparatus of the present invention, the pair of expander pins are movable between an active position located inside the parison and an inactive position where they are pulled out from the inside of the parison, and the pair of expander pins One of the expander pins is placed in a first position in cooperation with the other expander pin to form the parison into a flat shape, and a second position is located inside a predetermined portion of the parison where the edge of the film is set. and at least a position outside the parison opposite to one expander pin in the second position and a position opposite to the other expander pin. The present invention is characterized in that a film pressing roll is provided on one side for pressing the film against the parison in cooperation with the expander pin.

《Operations and effects of the invention》 In the blow molding device of the invention, one of the expander pins of the pair is
movable in cooperation with the other expander pin between a first position where the parison functions to flatten the parison and a second position inside a predetermined portion of the parison where the edge of the film is set; When attaching the film to the parison, one of the expander pins is moved to the above-mentioned predetermined portion of the parison, so that it is possible to sufficiently resist the pressing force of the film against the parison. The parison does not tilt during application, and the workability and accuracy of film application can be improved while preventing the film from tearing as described above during blow molding. Furthermore, a film pressing roll is provided opposite at least one of the expander pins to press the film supplied to the outer peripheral surface of the parison, thereby preventing the film from being fused to the parison. I can help.

<<Example>> Hereinafter, a blow molding apparatus according to an example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a blow molding apparatus 1 according to an embodiment of the present invention.

The blow molding apparatus 1 includes an accumulator head 3 for extruding a heated and melted thermoplastic resin as a base material into a parison 2, and a pair of molds 4, 4 located symmetrically about the center line of the parison 2.
, a blow pin 5 for blowing compressed air into the inside of the parison 2, and a product take-out device 7 for taking out the molded product 16 from the molds 4, 4 after blow molding.
It is equipped with Above storage head 3
is configured to be rotatable in order to rotate the parison 2 in order to attach a film to the outer peripheral surface of the parison 2, which will be described in detail later.

The product take-out device 7 includes the blow molding device 1
The guide rail 11 is fixed at one end to the frame 8 of the mold 4, and extends in a direction (back and forth direction) perpendicular to the opening/closing direction (left and right direction) of the molds 4, 4, and whose other end is fixed to the support 9. It includes a take-out part 12 that is slidably provided, and a chain drive part 13 that slides the take-out part 12. The take-out portion 12 is provided parallel to the guide rail 11, and as shown in FIG.
A pair of arms 15, 1 opened and closed by 4, 14
5. Further, during blow molding, the tip of the blow pin 5 is held by a lifting device located inside the parison 2 by a support stand 18 (see FIG. 6) supported by a vertical drive device (not shown). On the other hand, when the molded product 16 is taken out at the end of blow molding, the tip thereof is held in a lowered position below the lower end surface of the molded product 16.

The blow molding apparatus 1 also includes a film roll 22 for continuously supplying the parison 2 with a film 17 to be attached to the outer peripheral surface of the molded product 16. As shown in FIG. 3, this film roll 22 is provided at the rear of the molds 4, 4 on the opposite side to the product take-out device 7, and is provided in the blow molding device 1.
The frame 8 can be freely rotated around a shaft 22a fixed to the bed portion 8a of the frame 8.

The film roll 22 stores the film 17 in a roll shape, and can unwind the film 17 by rotating in a predetermined direction. This unrolled film 1
A film supply device 30 is provided to supply the film 7 to the parison 2. As shown in FIG. 3, FIG. 4, and FIG. The cutter 32 that cuts the film 17 by moving vertically along the film roll 22 and the edge of the film 17 fed out from the film roll 22 are held by suction by the vacuum cleaner. A film feeder 33 that moves from a nearby position to a position of the parison 2 and supplies and attaches the edge of the film 17 to a predetermined part of the parison 2.
It is equipped with

The film feeder 33 has a carriage portion 34 and is movable, and is also provided with a chain drive device 35 for moving from a position near the film guide 31 to a position near the parison 2. An edge suction support member 36 for suctioning and supporting the edge of the film 17 is slidably provided on the upper surface of the truck portion 34 so as to be able to move toward and away from the parison 2. A large number of fine holes are distributed and provided on the surface of the edge suction support member 36 on the parison 2 side, that is, the surface thereof, and these fine holes are arranged in the passage 3.
The film 17 is connected to a vacuum source (not shown) via the film 17, so that the edge of the film 17 is attracted to this surface. An air cylinder 38 is disposed on the back surface of the edge suction support member 36, and the air cylinder 38 advances the edge suction support member 36 to place the edge of the film 17 at a predetermined position on the parison 2. It's starting to be forced on people.

An expanding device 40 for preforming the parison 2 having a circular horizontal cross section into a flat shape is provided on the support base 18 that supports the blow pin 5.
As shown in FIG. 7, this expanding device 40 includes a pair of expander pins 41 and 42 provided symmetrically with respect to the blow pin 5. These expander pins 41 and 42 are
Each of them is formed telescopically so that it can be expanded and contracted. Further, the expander pins 41 and 42 are arranged on sliding members 45 and 46 that are slidably attached to a pair of rails 43 and 44 that extend in parallel in a direction perpendicular to the opening and closing direction of the molds 4 and 4. and is configured to be movable in the direction in which the rails 43, 44 extend. The sliding members 45 and 46 are provided with air cylinders 47 and 4, respectively.
8 is attached, and this air cylinder 4
7,48 by two expander pins 4
1 and 42 are moved toward and away from each other around the blow pin 5.

One of the two expander pins 41 and 42, that is, the expander pin 41 is further arranged on a second sliding member 49 movably provided on the sliding member 45, and The first position is indicated by a solid line in the figure, and the second position is indicated by an imaginary line.
The air cylinder 50 is in charge of the movement of the solid line.
When the expander pin 41 is in the first position, it performs an expanding action, and when it is in the second position, it grips the edge of the film 17 and faces the film feeder 33 that has supplied it. The parison 2 is maintained at the desired position by opposing the pressing force of the film feeder 33.

On the other hand, facing the other expander pin, that is, the expander pin 42, a film pressing roll 51 is arranged so as to be able to move towards and away from the expander pin 42, and its movement towards and away from the expander pin 42 is controlled by an air cylinder 52. conduct. The parison 2 is placed between the film pressing roll 51 and the expander pin 42.
By moving the film pressing roll 51 toward the expander pin 42, the parison 2 of the film 17 is
Helps attach to the outer peripheral surface. The accumulator head 3 is rotatable as described above, and by rotating the parison 2 with the film 17 in contact with the outer circumferential surface of the parison 2, the film 17 is moved onto the outer circumferential surface of the parison 2. It is designed to be pasted on the entire area. The expander pin 42 also functions to maintain the parison 2 at a desired position against the pressing force of the film pressing roll 51.

Note that another film pressing roll 51 having the same structure may be provided at a position facing the expander pin 41 shown by dotted lines in FIG.

A method of molding a molded product having a film pasted on its outer surface using the blow molding apparatus 1 configured as described above will be described below in the order of steps.

First, a parison 2 made of thermoplastic resin is preformed and extruded by the accumulator head 3.

Next, the pin drive device (not shown) is activated to raise the support base 18, thereby setting the blow pin 5 and expander pins 41, 42 to be located inside the parison 2. .

Next, the expander pins 41 and 42 are expanded. Note that this extension is preferably performed by an electric motor.

Next, the film feeder 33 is moved toward the parison 2, and when the film feeder 33 reaches the parison, it is stopped, and the air cylinder 38 is activated to move the edge suction support member 36 toward the parison. Once moved, the film 17 is affixed to the parison at a predetermined position. Prior to this, the air cylinder 50 is operated to move the expander pin 41 to the second position shown by imaginary lines in FIGS. 4 and 7. When this pasting is completed, the film feeder 33 is returned to its initial position near the film guide 31. At this time, almost simultaneously, the air cylinder 52 is operated to position the film pressing roll 51 at a position where it is almost in contact with the outer peripheral surface of the parison 2.

Thereafter, the accumulator head 3 is rotated to wrap the film 17 over the entire outer peripheral surface of the parison 2. After the winding of the film is completed, the rotation of the accumulator head 3 is stopped. After the accumulator head 3 is stopped, the expander pins 41 and 42 are contracted, and then the expander pin 41 is returned to the first position, and the air cylinder 4
7, 48, and the expander pin 4 is
1 and 42 are moved away from each other, the cross-sectional shape of the lower end of the parison 2 is changed from circular to flat, and the film pressing roll 51 is also retreated to the retracted position.

In the film feeder 33, the edge of the film 17 is held by suction for the next forming, and in this state, the cutter 32 is operated to cut the film 17. Thereafter, the molds 4, 4 are closed, and compressed air is blown into the parison 2 through the blow pin 5 to perform blow molding. After the blow molding is completed, open the molds 4, 4, and at the same time press the blow pin 5.
is lowered to a lowered position where its tip is located below the lower end of the molded product for the next cycle.

Finally, the take-out section 12 of the product take-out device 7
is moved back toward the product take-out side, the molded product 16 is taken out, and one cycle of the molding process is completed.

[Brief explanation of the drawing]

FIG. 1 is a front view of a blow molding device according to an embodiment of the present invention, FIG. 2 is a plan view of a take-out section of a product take-out device used in the blow molding device, and FIG. 3 is a blow molding device shown in FIG. 1. FIG. 4 is a schematic plan view of the film feeding device shown in FIG. 3, FIG. 5 is a side view of the film feeding device shown in FIG. 3, and FIG. 6 is a front view of the film feeding device of the device. FIG. 7 is a front view of the expanding device, which is the main part of the blow molding device, and FIG. 7 is a plan view of the expanding device shown in FIG. 1...Blow molding device, 2...Parison, 4...
...Mold, 41, 42...Expander pin, 51
...Roll for pressing film.

Claims (1)

[Scope of utility model registration request] a pair of expander pins located inside the hollow parison to flatten the parison; a film roll for supplying a film to be applied to the outer peripheral surface of the parison; A blow molding apparatus having a film feeder that is set on a predetermined portion of the outer circumferential surface of the parison, and a rotational drive means that rotates the parison, the pair of expander pins being at an operating position located inside the parison;
The parison is movable between an inactive position pulled out from inside the parison, and one of the pair of expander pins cooperates with the other expander pin to flatten the parison. and a second position inside the predetermined portion of the parison where the edge of the film is set, and the second position is outside the parison. A film pressing roll that cooperates with the expander pin to press the film onto the parison is provided at at least one of a position opposite to one of the expander pins and a position opposite to the other expander pin. Characteristic blow molding equipment.