JPS5829210B2 - Bubble internal cooling type rotary inflation die - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inflation die for forming a film by an inflation method.

In a device that forms film using the inflation method, a fixed die is used to blow up a bubble, and when the bubble is wound up, the film is deflected (circumferential variation in thickness).
This has the drawback that a satisfactory product cannot be obtained due to the formation of bulges and the concentration of wrinkles in these areas.

In order to prevent this, conventional methods have been taken to eliminate the above-mentioned drawbacks by employing a rotary inflation die equipped with a rotating device.

Also, in recent years, a method of cooling the film from inside by replacing the air inside the bubble has been attracting attention as a means of measuring the capacity of an inflation film forming apparatus.

However, when this method is adopted, it is not possible to install a rotating device like the conventional one in order to provide an air exchange tube in the center of the die, and therefore a fixed die is currently used.

The present invention solves these problems and provides a bubble internal cooling type rotary inflation die that can employ a rotary inflation method while using a bubble internal air replacement method.

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1 and Fig. 2, 1 is the dispensing hardware 2 of the dice.
The die adapter 4 of the extruder (not shown) is connected to the resin introducing section 3 of the extruder, and 4 is a closing plate. It is divided into the flow of

It should be noted that the side feed type or other commonly used systems may be adopted as the distribution mechanism crosspiece.

Reference numeral 6 denotes a fixed part connecting body which is connected to the distribution hardware 2 with bolts, and is provided with a number of branch passages 7 passing through it, corresponding to, for example, eight flows at the distribution end portion 5 of the distribution hardware 2. , the upper end portion communicates with a semicircular annular groove portion 8.

Reference numerals 9 and 10 denote an inner ring and an outer ring that are fitted and planted on the fixed part connecting body 6 along the inner and outer edges of the semicircular annular groove 8, and the opposing space is a cylindrical fixed one-rotation connecting space. It is configured in section 11.

Reference numeral 12 denotes an inner sliding plate mounted on the upper surface of the fixed part connecting body 6 on the inner peripheral side than the inner ring 9, and 13 denotes a sliding plate mounted on the upper surface of the fixed part connecting body 6 on the outer peripheral side than the outer ring 10. It is.

Reference numeral 14 denotes a rotating part connecting body connected to the fixed part connecting body 6, which is externally fitted onto the inner ring 9 and the outer ring 10, leaving the fixed one-rotation connecting space 11, and is connected to the inner and outer sliding plates 12. It is supported on 13.

A roller bearing support 15 is connected to the rotating part connecting body 14 with a bolt, and the roller bearing 16 is held by a roller bearing presser 17 connected to the fixed part connecting body 6.

Reference numeral 18 denotes, for example, 16 diagonal passages arranged in a ring in the rotary part connecting body 14 so as to communicate with the cylindrical fixed one-rotation connecting space 11. For example, eight spiral body introduction passages 19 are formed and arranged in an annular shape, and penetrate through the upper surface.

Reference numeral 20 denotes a rotational drive device that drives the rotating part connecting body 14 one rotation via an annular rotating gear 21 fixed thereto.

Reference numeral 22 denotes a spiral body that is connected to the rotating part connecting body 14 with a spiral groove introduction passage 23 that communicates with the spiral body introduction passage 19, and a spiral groove that communicates with the spiral groove introduction passage 23 on its outer periphery. It has 24.

25 is an outer cylinder that is fitted and connected to the spiral body 22, 26 is an inner lip that is connected to the spiral body 22, and 27 is an outer cylinder 2.
5, and between the inner lip 26 and the outer lip 27 is the spiral groove 2 of the spiral body 22.
4 is formed into a cylindrical homogeneous passage portion 28 communicating with the passageway 4, and the open end thereof is formed into an annular lip portion 29.

Reference numeral 30 denotes a thickness unevenness adjusting bolt attached to the outer lip 27.

Reference numerals 31 and 32 denote an outer cylinder and an inner cylinder for air displacement arranged at the center of the die, both of which are configured to rotate together with the die rotation part, and the displacement air is supplied to the outer cylinder 31 and the inner cylinder 32.
It is supplied from between the inner cylinder 32 and discharged from the inner cylinder 32.

In addition, 33 to 36 are respectively distributed metal items 2. Fixed part connection body 6
．． A heater 37 is attached to the outer periphery of the outer cylinder 25 and the outer lip 27, and a die support 37 is attached to the distribution hardware 2.

In FIG. 3, reference numeral 38 denotes a horizontal scraping pin, which is fixed at a position corresponding to the fixed rotation connection space 11 of the rotating part connecting body 14 and at a position that does not overlap with the opening position of the oblique passage part 18. - at least one projecting inward of the rotational connection space 11;
There are one.

This is to eliminate the possibility that a portion where the resin does not flow, that is, a stagnation portion of the molten resin, may occur at a position between the openings of the distribution passage portion 7 in the fixed one-rotation connection space 11, and deterioration may occur. The molten resin in the annular groove 8 and the fixed one-rotation connection space 11 is constantly disturbed by the resin scraping pin 38 that constantly moves within the fixed one-rotation connection space 11.
No stagnation occurs.

Next, its effect will be explained.

The resin introduced into the resin introduction part 3 is divided into eight streams in the distribution part 5, and is supplied from the eight branch passages 7 to the annular groove part 8 and the fixed one-rotation connection space part 11,
Then, as described above, without generating a stagnation part, it is evenly sent to, for example, eight spiral introduction passages 19 and 23 through the rotating diagonal passages 18, for example, 16, and passes through the spiral groove 24 into a cylindrical shape. It is homogenized in the homogeneous passage section 28 and blown out from the cylindrical lip section 20 to form a bubble 39.

As described above, according to the present invention, although the bubble internal cooling method can be used to efficiently manufacture the product, since the rotary inflation method is used, the occurrence of curling can be reliably prevented.

Furthermore, if both the outer cylinder and the inner cylinder for air displacement are made rotatable, it is possible to eliminate the curl caused by the displacement air.

Furthermore, if a resin scraping pin is provided, it is possible to prevent molten resin from accumulating in the rotating connection portion, thereby eliminating product deterioration.

Note that since the air displacement outer cylinder and inner cylinder are provided through the center of the die, the sealing device thereof is extremely simple.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view thereof, and FIGS. 2 and 3 are perspective views showing essential parts of a rotating connection part. 2... Distribution hardware, 6... Fixed part connection body, 7... Diversion passage section, 8... Annular groove part, 9, 10... Inner and outer rings, 11... Fixed one rotation Connection space section, 14...
-Rotating part connecting body, 18... Oblique passage part, 19... Spiral body introduction passage part (through passage part), 24... Spiral structure part, 29... Lip part, 31.32...・Outer cylinder and inner cylinder for air displacement.

Claims (1)

[Claims] 1. A fixed part connecting body that penetrates through a branching passage section that divides the resin introduced from the extruder into a plurality of flows arranged in an annular shape, and a fixed part connecting body that is rotatably connected to the fixed part connecting body. a rotating part connecting body having a plurality of through passages arranged in an annular shape communicating with the plurality of branch passages of the fixed part connecting body via a cylindrical fixed one rotation connecting space; A means for preventing molten resin from accumulating in the cylindrical stationary one-rotation connection space, and a bubble for displacing air for internal cooling disposed through the center of the stationary part connection body and the rotary part connection body. A bubble internal cooling type rotary, characterized in that an outer cylinder and an inner cylinder are provided as a supply/discharge port, and a through passage of the rotating part connecting body is communicated with a bubble forming lip part interlocked with the rotating part connecting body. inflation dice.