JPH038257B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field> The present invention relates to an inflation molding machine that extrudes synthetic resin into tube-shaped bubbles, folds the bubbles flat, and passes them through a cooling liquid tank to form tube strips of a predetermined width. The present invention relates to a bubble stabilizer support device.

<Prior Art> Prior to this application, this type of bubble stabilizer support device was as shown in FIGS. 2 and 3.
A male threaded portion 12 is provided at the lower end of one hollow tube 10 to be screwed into the air supply port 11 of the molding die of the inflation molding machine, and the upper end is provided for blowing air into the bubble B. A plurality of air blowing holes 16 are provided near the lower end of the hollow tube 10 to communicate with an internal air passage 15 formed over the entire length of the hollow tube 10.

Prior to attaching and supporting the bubble stabilizer A to such a hollow tube 10 and performing inflation molding, the following preparatory work is performed.

That is, in order to guide the resin extruded from the resin discharge port of the molding die as a bubble B to the upper nip roller 17, the upper end opening 13 of the hollow tube 10 attached to the air supply port 11 of the molding die is closed with a hand H, and the lower While blowing air from the air blowing hole 16 of the molding die, the molten resin F is extruded in an annular shape from the resin discharge port of the molding die, and the molten resin F is blown up along the bubble stabilizer A, and the upper edge is lifted by hand. Upper end opening 1 of empty tube 10
3 is opened, and when the hollow tube 10 is lifted to the upper end, the upper edge of the molten resin is pinched by hand to form a closed end and a bubble B is formed. Next, the blower is started so that the diameter of this bubble B becomes a desired value, and the air supply port 11 of the molding die is connected to the upper opening 13 of the hollow tube 10.
While supplying air into the bubble B through the bubble B, the bubble is formed and lifted to the upper nip roller 17.
Next, it is guided to a winder 20 through a bubble breakage diameter detection device 18 and a cooling device 19. Next, the inflation molding machine is switched to continuous operation, and at this time, the fold diameter detection device 1 is operated so that the bubble fold diameter becomes the desired value.
The blower is started and stopped based on the value detected in step 8, and the air pressure inside the bubble B is adjusted through the air supply/discharge port of the forming die to form a bubble with a desired folding diameter.

Therefore, when blowing up the annular molten resin in the preparation stage for continuous bubble molding, the operator should cover the upper end opening 13 of the hollow tube 10 with one hand and blow the molten resin with the other hand. It is necessary to pick up the hollow tube 10 to the upper end, which is a rather troublesome operation, and at the same time, when transitioning from the blowing operation to the continuous bubble operation, it is discharged from the upper end opening 13 of the hollow tube 10 into the bubble B. Since air is also blown out from the air outlet 16 at the bottom, the air supplied into the bubble cannot be used 100% effectively for setting the bubble fold diameter, and when changing the bubble fold diameter, When the bending diameter is to be changed significantly, the bubble B is blown into the hollow tube 10 near the resin discharge port of the molding die and below the bubble stabilizer A by the air blown out from the air outlet 16 provided at the bottom of the hollow tube. The known bubble in which a bubble stabilizer is provided in the hollow tube has the drawback that the bubble B expands abnormally to the outside without being attached to the hollow tube, which interferes with changing the bubble diameter, and makes it difficult to obtain a bubble B with the desired diameter. Has a stabilizer.

[Objective] The present invention relates to a bubble stabilizer support device for an inflation molding machine that improves the drawbacks of the prior art, ensures blowing up of molten resin, and smoothly changes the diameter of the bubble.

<Structure> The object of the present invention is to provide a bubble stabilizer support device for use in an inflation molding machine, which includes an outer cylinder with open upper and lower ends that supports a bubble stabilizer on its circumferential surface, and an outer cylinder that is fitted into the outer cylinder with a gap. The lower end of the outer cylinder communicates with the air supply port of the molding die, and near this lower end, a plurality of air blowing holes are provided that penetrate the peripheral wall of the outer cylinder. is provided with an air passage with a top and bottom opening over its entire length, and a manual knob for opening and closing this air passage is provided at the upper end of the hollow inner cylinder that protrudes from the upper end of the outer cylinder, and an air blowing hole of the outer cylinder is provided. An inflation molding machine characterized in that a valve is integrally provided at the lower end of the hollow inner cylinder, the valve selectively opening into the gap and an air supply port of the molding die with which the lower end of the outer cylinder communicates. This is achieved by the present invention, which is a bubble stabilizer support device.

Next, typical embodiments of the present invention will be described based on the drawings.

4 and 5, reference numeral 30 denotes a bubble stabilizer support device, which supports the bubble stabilizer A on its circumferential surface, and includes an outer cylinder 40 with open upper and lower ends, and a gap S in this outer cylinder 40. The main component is a hollow inner cylinder 50 that is fitted at a certain angle.

The hollow inner cylinder 50 is installed to be able to move up and down in the axial direction of the outer cylinder 40 and to be rotatable around the axis.

An air passage 51 with open upper and lower ends is formed in the center of the hollow inner cylinder 50, and the hollow inner cylinder 51 is located at the upper limit position.
A manual knob 52 is provided at the upper end of the hollow inner cylinder 50 protruding from the upper end 40b of the outer cylinder 40.

On the other hand, the open lower end 40a of the outer cylinder 40 is provided with a male thread 41 that is threaded into the air supply port 11 of the die of the inflation molding machine, and this lower end 40a communicates with the air supply port 11. Near the lower end 40a of the outer cylinder 40, a plurality of air blowing holes 42 are formed at equal angular intervals in the peripheral wall of the outer cylinder 40. In a pair of grooves 43 formed by cutting out the peripheral wall, a positioning pin 54 is installed horizontally in the hollow inner cylinder 50 below the socket 52 and is detachable at both ends thereof.

This positioning pin 54 is located at the upper end 40b of the outer cylinder 40.
When the hollow inner cylinder 40 is positioned at the upper limit, the air outlet 42 is communicated with the air supply port 11, and the positioning pin 54 falls into the L-shaped groove 43 of the outer cylinder 40 and engages. , when the hollow inner cylinder 40 is located at the lower limit, the air outlet 42 and the air supply port 11
The air outlet 42 is connected to the hollow inner cylinder 50.
A valve 55 that opens into the gap S between the hollow inner cylinder 50 and the outer cylinder 40 is integrally provided at the lower end of the hollow inner cylinder 50.
5 is formed by a flange extending over the entire outer circumference of the hollow inner cylinder 50, and also has the function of preventing air from the molding die air supply port 11 from directly flowing into the gap S.

<Function> The function of the bubble stabilizer support device 30 of the present invention having the above configuration will be described below.

During molten resin blowing work, the hollow inner cylinder 50 is set at the upper limit position, and only the air blowing hole 42 is communicated with the air supply port 11 of the molding die by the action of the valve 55, and the air passage 51 of the hollow inner cylinder 50 is closed. 52, the molten resin is blown up from the resin discharge port of the molding die, and the molten resin is evenly distributed with both hands onto the bubble stabilizer A installed at an appropriate height around the outer cylinder 40. along the top of the hollow inner cylinder.

In this state, the positioning pin 54 of the hollow inner cylinder 50
is dropped into the L-shaped groove 43 from the upper part of the outer cylinder 40, rotated slightly around the axis, the pin 54 is engaged with the horizontal hole 43a of the groove 43, and the hollow inner cylinder 5 is
0 is set to the lower limit position, and by the action of the valve 55, the air blowing hole 42 is communicated with the gap S between the outer cylinder 40 and the hollow inner cylinder 50, and is not communicated with the air supply port 11, and the air passage of the hollow inner cylinder 50 is opened. 51 is opened by the action of Kotoku 52,
All the air from the air supply port 11 is discharged from the upper end of the hollow inner cylinder 50.

With this hollow inner cylinder 50 set at the lower limit position, the tip of the molten resin blown up and picked up is closed to form a bubble, and the air passage 5 of the hollow inner cylinder 50 is
Continuous inflation molding is carried out using air blown out from the upper end of the mold to adjust the bubble diameter to a desired value, as in the conventional method. At this time, since the lower air blowing hole 43 and the inside of the bubble B communicate through the gap S, the internal pressure is the same as that of the bubble B, and the inner pressure is the same as that of the bubble B. The internal pressure of the bubble space is maintained.

When changing the bubble fold diameter during continuous inflation molding, air is discharged from the upper end of the hollow inner cylinder 50 into the bubble B, or the molding die is The bubble diameter can be changed by exhausting air through the tube. At this time too,
Air supplied from the direct molding die does not flow into or out of the air blowing hole 43 of the outer cylinder 50.

<Effects> The present invention configured and operated as described above has the following effects.

Not only during the transition from bubble blowing to continuous molding, but also when changing the bubble fold diameter, all the air supplied from the air supply port 11 of the molding die to the bubble stabilizer support device 30 is the air in the hollow inner cylinder 50. The air can be blown into the bubble B through the passage 51, and is not discharged at all from the air blowing hole 43 provided at the bottom of the outer cylinder 50. When changing to a larger diameter bubble, the air in the bubble stabilizer A and the molding die is The bubble located between the supply ports 11 expands outward in a strange shape and does not interfere with changing the bubble diameter, and the bubble fold diameter can be smoothly changed to a large diameter, and the bubble diameter can be changed to a small diameter bubble. Even when the air blowing hole 43 of the outer cylinder 40
communicates with the inside of the bubble B through the gap S and becomes equal pressure, so it is no longer pressed by external pressure and comes into close contact with the circumferential surface of the outer cylinder 40, and due to this close contact, the frictional force between the outer cylinder 40 and the bubble B increases. It is possible to eliminate the problem of the bubble B growing larger and breaking when the bubble B is taken over.

When the bubble is blown up, the air passage 51 can be closed by the action of the cock 52, and the hollow inner cylinder 4 can be closed as in the conventional case.
The upper end of the blown-up molten resin can be uniformly lifted and guided above the hollow inner cylinder 40 using both hands without the need to cover the upper end of the molten resin with one's hand.

The bubble stabilizer support device 30 of the present invention, which performs continuous bubble formation as described above, is used together with a cooling ring that cools the outer peripheral surface of the bubble to obtain bubbles with a high expansion ratio and a large folded diameter. The bubble can be cooled from the inside and outside by the air circulating inside the bubble and the air from the cooling ring without causing abnormal expansion in the lower part of the support device 30.

<Effects of the embodiment> When the knob 53 of the knob 52 is horizontal, the air passage 51 is closed, and when it is vertical, the air passage 51 is closed.
When opened, the bubble stabilizer support device 30 can be set for continuous molding from the outside of the bubble B depending on the position of the knob 53 and the engagement/disengagement position of the positioning pin 54 with the L-shaped groove 43. It can be determined at a glance whether or not the bubble is being molded properly, and defective bubble molding can be prevented.

The engagement between the horizontal hole 43a of this L-shaped groove 43 and the positioning pin 54 prevents the hollow inner cylinder 50 from moving away from the lower limit position due to the air pressure passing through the upward air passage 51 during continuous bubble molding. can be prevented.

The hollow inner cylinder 50 of the embodiment described above is equipped to be able to move vertically and rotate freely, but the valve 55 at the lower end of the hollow inner cylinder 50 is formed in a rotary type, and the hollow inner cylinder 50 can be rotated around its axis. However, the present invention is the same even if the structure is such that the air outlet 43 communicates with and does not communicate with the air supply port 11.

[Brief explanation of the drawing]

The figures relate to the present invention; Fig. 1 is a schematic diagram of an inflation molding machine, and Fig. 2 shows a method for blowing up bubbles using a hollow tube, which is a conventional bubble stabilizer support device. Figure 3 to explain the state in which
The figure shows a state in which the upper end of the molten resin is closed using a hollow tube similar to that in Fig. 2, and Fig. 4 shows a state in which blowing work is performed using a bubble stabilizer support device according to an embodiment of the present invention. FIG. 5 is a diagram showing a state in which bubbles are continuously formed using the bubble stabilizer support device of FIG. 4. Explanation of main symbols in the figure, 11...Air supply port,
30...bubble stabilizer support device, 40...outer cylinder,
43... Air blowout hole, 50... Hollow inner cylinder, 51...
...Air passage.

Claims (1)

[Claims] 1. A bubble stabilizer support device used in an inflation molding machine includes an outer cylinder with open upper and lower ends that supports the bubble stabilizer on its circumferential surface, and a bubble stabilizer that is fitted into the outer cylinder with a gap. The lower end of the outer cylinder communicates with the air supply port of the forming die,
A plurality of air blow-off holes are provided near the lower end of the outer cylinder and penetrate through the peripheral wall of the outer cylinder.In the center of the hollow inner cylinder, an air passage with vertical openings is provided along its entire length. , provided at the upper end of the hollow inner cylinder protruding from the upper end of the outer cylinder, the air blowing hole of the outer cylinder being selectively opened to the air supply port of the molding die with which the lower end of the outer cylinder communicates with the gap; A bubble stabilizer support device for an inflation molding machine, characterized in that a valve is integrally provided at the lower end of the hollow inner cylinder. 2 The hollow inner cylinder is equipped to be able to move up and down, and the air outlet is connected to the air supply port at its upper limit position, the communication is cut off at the lower limit position, and the air outlet is opened in the gap between the outer cylinder and the hollow inner cylinder. 2. A bubble stabilizer support device for an inflation molding machine according to claim 1, wherein a flange is integrally provided at the lower end of the hollow inner cylinder as a valve. 3 The hollow inner cylinder is equipped to be able to move vertically between the first and second positions, and the positioning pin, which is implanted horizontally in the lower part of the hollow inner cylinder across its axis, extends in an L-shape from the upper end of the outer cylinder. The positioning pin can be freely inserted into and removed from the notched groove, and when it is at the lower limit position of the hollow inner cylinder, the positioning pin
3. The bubble stabilizer support device for an inflation molding machine according to claim 2, which engages with the horizontal hole of the character-shaped groove and engages with the upper end surface of the outer cylinder when it is at its upper limit position. 4. The bubble stabilizer support device for an inflation molding machine according to claim 1, wherein the hollow inner cylinder rotates around its axis, and the valve is a bubble that can freely rotate back and forth.