JPS5945109A - Method and apparatus for supplying additive in extruder - Google Patents

Abstract

PURPOSE:To remove effects due to the temperature of a feed port wall and heated steam from a compression portion, etc. when the main material and additive are supplied together by a method wherein additive is supplied cylindrically from a funnel chute to the feed port of an extruder cylinder, while the main material is supplied from the side of a box body covering the tube portion of the chute makig a cylindrical form in the box body and supplies the main material to the feed port in the manner wrapping the additive with cylinder-formed main material. CONSTITUTION:Melted high-temperature main material is supplied from a line 1 in cylinder form through the main material passage 4 and the feed port 5 into an extruder cylinder 6. Additive is supplied in cylindrical form from a chute 7 into the extruder cylinder 6 through the feed port 5 and is wrapped with the main material. The tube portion of the chute 7 that comes in contact with the main material is cooled because water runs in a compartment 8 and the additive is not effected by the heat from the tube portion. Because the outer circumference of the compartment 8 is covered with a compartment 9 having air layer, the melted main material is not cooled but flows down through the main passage 4 without changing its temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a feeding method and apparatus for feeding additives to an extruder simultaneously with main raw materials.

During kneading and extrusion in an extruder, main raw materials and additives such as modifiers or fillers are often fed simultaneously via a feeder. Among these additives, when the melting point is low, the following problems occur and production is hindered.

1) Under the influence of the temperature around the feeder, the additives melt and form a layer around the two feed ports, making it impossible to stably and continuously feed them together with the main raw materials.

2) The melted additives deteriorated over time and were intermittently downgraded to the feedlot, adversely affecting the product.

3) The additive was melted by the return of the heated gas from the extruder compression section and adhered to the feedlot. As a result, continuous supply became impossible or the mixing ratio changed.

Even if the additive is inorganic and has a high melting point, the additive may stagnate due to the build-up and adhesion of the main raw material at one feed port, or it may absorb moisture under the influence of the heated gas from the compression section and adhere to the feedro wall. It was impossible to maintain a stable continuous supply. For this reason, many proposals have been made regarding the shape of the chute and the throwing position ta, but none have completely solved the above-mentioned drawbacks.

The present invention has been made from this point of view, and its purpose is to provide a method for supplying additives in an extruder that is not affected by feedflow wall temperature, heated steam from the compression section, etc. when main raw materials and additives are supplied simultaneously. and equipment.

The present invention will be explained below with reference to figures showing one embodiment. First, the case where the main raw material is melt feed will be explained. The main raw material (1, not shown) flows through the pipe 1 from the face hole 3 of the box-like body 2 into the main raw material passage 4, which is a circular hole in the box-like body 2, where it becomes a cylindrical body. The feed is fed into the extruder cylinder/6 from the port 5. - A tensile agent (not shown) is introduced into a chute 7 provided at the center of the box-like body 2 (from a feeder not shown) and is fed from the feeder 5 into the extruder cylinder 6. A partition A8 is provided on the outer periphery of the cylindrical portion which is shaped like a funnel, and the chute 7 is cooled by passing water between the inside of the partition A8 and the outside of the cylindrical portion. is partition B with an air layer.
9 is provided, and this air layer may be stationary or flowing. Note that the reference numeral 10 is a screw.

Next, the operation of the present invention will be explained. The melted main raw material i is fed from the high temperature main raw material i pipe 1 through the main raw material passage 4 of the box-shaped body 2 into a cylindrical shape from the feeder 5 into the extruder cylinder/6. On the other hand, since water passes through the partition A8 in the cylindrical portion where the additive is stored, the cylindrical portion is cooled, and the additive is not affected by heat from the cylindrical portion. Further, since the outer periphery of the partition A8 is covered by the partition B9 having an air layer, the melted main material flows down the main material passage 4 while maintaining its temperature without being cooled. However, the melted main raw material is A
The amount should be such that it does not rise so much that it touches the surface.

In the above explanation, the main raw material was melted, but when it is in powder form, the temperature is room temperature and the additives are not heated, so partition A8 and partition B9 are unnecessary, but 40 main raw material passages are required. It is preferable to increase the passage area.

As described above, the method and apparatus for supplying additives to an extruder according to the present invention supplies additives in a cylindrical manner from a funnel-shaped chute to the feedlot of an extruder cylinder, and supplies the main raw material to a box that covers the cylindrical portion of the chute. By feeding from the side of the shaped body, it is formed into a cylindrical shape inside the box-shaped body, and this cylindrical main raw material is configured to enclose the additive and supply it to the feeder.

Therefore, it has the following advantages.

1) The additive is no longer affected by the build-up in the feeder of the extruder cylinder.

2) It is no longer affected by the heated gas returning from the extruder cylinder compression section.

3) Additives are no longer affected by heat from raw materials even at low melting points.

4) Even the melted main raw material is no longer affected by the heat of additives.

5) Stable continuous supply is now possible while keeping the mixing ratio of main raw materials and additives constant.

[Brief explanation of drawings]

The figure is a sectional view of one embodiment of the present invention. 2... Box-shaped body, 5... Feedro, 6... Extruder cylinder, 7... Chute. Applicant: Toshiba Machine Co., Ltd.

Claims (1)

[Scope of Claims] 1) Additives are supplied in a cylindrical manner from a funnel-shaped chute to the feedlot of an extruder cylinder, and the main raw material is fed from the side of a box-shaped body that covers the cylindrical portion of the chute to form a box-shaped body. A method for supplying additives to an extruder, in which the additives are formed into a cylindrical shape inside the extruder, and the additives are enclosed in the cylindrical main raw material and supplied to the feed port. 2) A funnel-shaped chute with its tip open to the feedro of the extruder cylinder for supplying additives, and a cylindrical part of the chute inserted into the interior of the chute for supplying the main raw material, and its lower surface placed on the feeder port. An extruder additive supply device consisting of a box-shaped body placed in a