JPS588973B2 - Youyu Oshidashi Sochi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a melt extrusion apparatus for synthetic resins such as polyester, polyamide, polyolefin, etc.

More specifically, it relates to (1) a melt extrusion device that can change the discharge amount from a mold over a wide range by installing a plurality of extruders with the same or different discharge amounts in a series and switching the melt-extruded synthetic resin with a switching operation; It is an invention.

In the conventional technology, one extruder and one mold are set in one line, so the stable selection range of melt output is extremely narrow, and production is limited by the extruder output. Conditions are set.

For example, in film production, film products with various thicknesses are required, and in order to obtain thick films, it is necessary to reduce the film take-up speed, rolling speed, etc.

In the conventional technology, there was a problem in that it was difficult to produce multiple brands in one series, which was disadvantageous in terms of operating rate, production efficiency, etc.

An object of the present invention is to provide a melt extrusion device that can rationally produce multiple brands in one line.

Another object is to provide a melt extrusion apparatus that can improve operating efficiency during production and reduce capital investment.

That is, the present invention is a melt extrusion apparatus comprising two or more extruders, conduits connected to each extruder, a switching device, a kneading device, and a mold, and the extruders have mutually the same or different melt output amounts. Each of the conduits is engaged with each extruder, the conduits are assembled in the switching device, the amount of molten synthetic resin to be supplied from one or more extruders is selected by the switching device, and the switching device This is a melt extrusion device in which the synthetic resin that has passed through the device is kneaded in a kneading device and then supplied to a mold.

The present invention will be explained with reference to the drawings.

FIG. 1 shows an example in which two extruders with different melt discharge amounts are used.

Extruders 1a and 1b are engaged with conduits 4a and 4b and are coupled to switching device 2.

A kneading device 3 is provided between the switching device and the mold (not shown).

Now, when the synthetic resin is melted and discharged from one or both of the extruders, the molten synthetic resin flows to the switching device through one or both of the conduits.

This switching device has the effect of opening the conduit through which the synthetic resin is supplied, allowing the molten synthetic resin to flow in the direction of the mold depending on whether only one extruder is operated or when both extruders are used. It has the function of obtaining.

The molten synthetic resin that has passed through the switching device is kneaded by the kneading device, which averages out uneven thermal decomposition, uneven temperature, and uneven flow rate due to differences in residence time that occur when the synthetic resin flows in the conduit. become

Kneading devices include filters, spiral rotary blades (e.g., static mixer manufactured by K-EX), and changes in the cross-sectional area of flow channels (e.g., a combination of thick and narrow channels).
Those with the following functions can be applied.

As the mold, various types of known shapes (for example, molds, blown film dies, T-shaped dies, hollow molding dies, etc.) can be used depending on the purpose.

According to the present invention, the amount of synthetic resin supplied to the mold can be changed over a wide range in a stable state using the switching device.

For example, FIG. 2 shows the relationship between the screw rotation speed and the discharge amount of an extruder in the prior art, and the synthetic resin supply amount is determined within the range in which the screw rotation speed can be changed.

However, in the apparatus of the present invention, even if only one of the extruders with different extrusion rates is used, the output rate can be changed within a stable operating range of the screw rotation speed, as shown in Fig. 3. Therefore, the amount of molten synthetic resin supplied to the mold can vary considerably.

As a specific example, the discharge amount of the extruder 1a is 40 to 220 kg.
/ hour, when the discharge rate of extruder 1b is 200 to 800 kg/hour, when only one extruder is used, 40 to 800 kg/hour
g/hour of synthetic resin supply amount, and if used together, 1020 g/hour
k9/hour can be reached.

In the conventional system, the extruder for low discharge rate and the extruder for low discharge rate were separated in series, but in the present invention, they are integrated, making it possible to produce multiple brands in one series.

Furthermore, since the amount of synthetic resin used can be selected from a wide range in a short time without replacing the extruder, such as the screw or cylinder, opportunity losses are reduced and the operating rate is increased.

Furthermore, the production volume can be changed with efficiency with a single switching device, resulting in high workability.

Although the present invention installs multiple extruders in one production line, the equipment cost is small (generally, molds are more expensive than extruders, and film forming equipment requires rolling, heat setting, cooling, etc.). There is also an advantage (the equipment cost of the Hirotori equipment is enormous, so it is optimal to add an extruder in terms of equipment cost).

The present invention is the most rational melt extrusion device in the field of synthetic resin molding.

[Brief explanation of drawings]

FIG. 1 is a process schematic diagram showing one example of an embodiment of the apparatus of the present invention. FIG. 2 (conventional method) and FIG. 3 (apparatus of the present invention) are graphs showing the extruder screw rotation speed and the discharge (supply) amount of molten synthetic resin. In the drawings, ia and lb are extruders, 2 is a switching device, 3 is a kneading device, and 4a and 4b are conduits.

Claims (1)

[Claims] 1 Two or more extruders with the same or different melt discharge amounts, conduits that engage each extruder, a switching device to connect each conduit and guide it to the mold, and a kneading device installed between the switching device and the mold A melt extrusion device consisting of a mold and a mold.