JP3466659B2 - Twin screw extruder - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a complete meshing type co-rotating twin-screw extruder for mixing, kneading and other reactions of resins and other melts and liquids.

[0002]

2. Description of the Related Art Conventional full mesh type co-rotating type 2
As the axial extruder (hereinafter, simply referred to as extruder) in this section, the one shown in FIG. 4 or FIG. 5 is known.

An extruder whose essential part of the screw portion is shown in FIG. 4 is composed of two meshing screws (or kneading discs: in the above and below, they are simply referred to as meshing screws) 1, The pressing plates 2 and 3 are arranged at both ends of the screw 1, and the shafts 1a of the screw 1 that protrudes outward from the pressing plate 2 by covering the outer circumference of the screw 1 and 1 between the pressing plates 2 and 3 with the barrel 4. Is connected to an unillustrated shaft support portion and drive means. The two meshing screws 1 and 1 are the same, and they rotate in the same direction although detailed illustration is omitted. Reference numeral 5 in the figure denotes an injection hole through which resin and other materials are injected into the inner cavity of the barrel 4 and into a flow channel 6 formed between the outer surface of the meshing screw 1 and the inner wall of the barrel 4. The material is subjected to mixing, kneading, and other treatments while moving from the pressing plate 2 side to the pressing plate 3 side, and is extruded out of the apparatus through a die or the like (not shown). Of course, not only two meshing screws 1 but also a multi-axis screw having more than two screws are known.

In addition to the structure of the extruder shown in FIG. 5, which shows the main part of the screw portion in FIG. 5, the extruder has a structure similar to that of the extruder in FIG. a shaft screw 7,7 provided, press even plate 3
a configuration of arranging the a.

[0005]

By the way, in the conventionally known twin-screw extruder as described above, whether the material injected from the injection hole 5 into the barrel 4 is located at the position of the injection hole 5 in the flow path 6 or not.
Luo push even sometimes remaining between the plates 2. Normal,
The material entered through the injection hole 5 is pressed with a discharge port (not shown).
Flow to the side of the plate 3 and reverse to the side of the holding plate 2.
Since there is only a small amount of flow, reverse to the holding plate 2 side.
The residence time of the flowing material is that a long. Such stagnant material causes mixing of deteriorated substances and coloring in the extruded product in the case of resin mixing, continuous mixing, and the like.

The present invention has been made in view of such conventional problems, and substantially eliminates the retention of the material in the barrel,
An object of the present invention is to provide a twin-screw extruder capable of minimizing deterioration of materials such as resins, inclusion of deteriorated materials, and deterioration such as coloring by making the residence time uniform.

[0007]

In order to achieve the above object, a twin-screw extruder according to the present invention is a fully meshing type co-rotating twin-screw extruder having two or more meshing screws. continuously provided a uniaxial screw at one end each of the respective mating screw is obtained by a structure in which disposed at a position corresponding to said single shaft screw to feed the site materials.

In the twin-screw extruder according to the present invention, the material is supplied to the single-screw screw in a case or a barrel at a position corresponding to the end opposite to the connecting end with the meshing screw. It can be configured as a hole.

The twin-screw extruder according to the present invention may have a structure in which the material supply portion is provided in the barrel at an intermediate position in the flow direction of the material by the meshing screw.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a completely meshing type co-rotating twin-screw extruder according to the present invention will be described below with reference to the drawings.
It should be noted that, in the following, the same parts as those of the prior art will be denoted by the same reference numerals, and overlapping description will be omitted.

FIG. 1 shows the entire screw section of an embodiment of the twin-screw extruder according to the present invention. The extruder of the illustrated embodiment has substantially the same structure as the conventional extruder shown in FIGS. 4 and 5, but the two meshing screws 1, 1 have a small diameter single-screw screw 10, respectively at the base ends. Yes 10 and continuously provided to a pair of lumen push even provided inside the plate 2a 1
Each insert a single-screw 10, 10 in 1 and 11, a single-screw 10 continuous meshing screw 1 it is intended that it has configured to be rotatable integrally, respectively. In addition, the meshing screw 1 and the uniaxial screw which are integrated
The ew 10 supports the shaft 1a at a portion not shown.

An injection hole 12 communicating with the inner cavity 11 is provided between the two shafts 1a and 1a on the rear end surface of the pressing plate 2a.
It is injected into the barrel 4 and then flows into the barrel 4.

The screw shapes of the meshing screw 1 and the single screw 10 are shown in FIGS. 2 and 3 in the illustrated example.
However, since a single-screw screw has a wide range of shape selection, it may be selected according to various conditions such as the type of material and viscosity. Kneading screw is kneading
You can also select a disc. The position of the injection hole 12 is not limited to the position in the illustrated example, but may be any position near the rear end of the pressing plate 2a in the space formed by the inner cavity 11 and the uniaxial screw 10, either the upper surface, the lower surface, or the left and right side surfaces. It may be provided at a plurality of positions, or may be provided at a plurality of positions.

Next, the operation of this embodiment will be described. Injection hole 1
The material such as resin injected from 2 is extruded into the barrel 4 by the uniaxial screw 10 in the inner cavities 11 and 11, respectively, and the flow path 6 formed between the outer surface of the meshing screw 1 and the inner wall of the barrel 4 is pushed. The liquid flows in, is subjected to mixing, kneading, and other processing, and is extruded out of the apparatus through a die (not shown).

That is, since there is almost no space behind the material injection position in the flow direction, the amount of material that can stay in the flow path 6 in the barrel 4 is extremely small or almost completely absent. In addition, the meshing screw 1
Even when the same or different material is injected from the injection hole 5 provided at the middle position of the mixer and mixed and kneaded, the material is supplied from the single-screw screw 10 side. It will not occur.

[0016]

As described above, the twin-screw extruder according to the first aspect of the present invention has a single-screw screw continuously connected to each one end side of a twin-screw or two or more meshing screws that rotate in the same direction in a completely meshing type. Since it corresponds to the material supply site by making it possible to make the space located on the rear side of the flow smaller than the material injection position, the amount of material that can stay behind in the flow direction of the material is extremely small or almost The effect is that it can be lost. For this reason, deterioration of the material is eliminated, and in the case of a material such as a resin, coloring due to mixing of the deteriorated material is also eliminated, and the retention time of the material is uniform because the amount of retention is small, and the product properties can be improved accordingly. It is possible to obtain various and great effects such as being possible.

A twin-screw extruder according to a second aspect of the present invention is a case or barrel in which a material supply portion to a single-screw screw is provided at a position corresponding to an end portion opposite to a connecting end portion with a meshing screw. In addition to the above common effect, the space located on the rear side of the flow from the material injection position can be made extremely small or eliminated, and the retention amount of the material can be further reduced. The effect is that it can be reduced.

In the twin-screw extruder according to the third aspect of the present invention, since the barrel is provided with the material supply site at the midway position in the material flow direction by the meshing screw, in addition to the above-mentioned common effect, two or more kinds are provided. Even when injecting and processing different materials, the effect that the materials from the single-screw screw side can perform the processing such as mixing and kneading without causing leakage and retention of the material to the rear due to the supply can get.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an entire screw portion of an embodiment of a twin-screw extruder according to the present invention.

FIG. 2 is a cross-sectional view of a meshing screw portion of the example of FIG.

FIG. 3 is a cross-sectional view of a single screw unit of the example of FIG.

FIG. 4 is a sectional view showing an entire screw portion of a conventional twin-screw extruder.

FIG. 5 is a cross-sectional view showing the entire screw portion of another conventional twin-screw extruder.

[Explanation of symbols]

1 meshing screw 2, 2a, 3, 3a Presser plate 4 barrels 5 injection holes 6 Material flow path 10 Single screw 12 injection holes

Claims (3)

(57) [Claims] 1. A fully meshing co-rotating twin screw extruder having two or more meshing screws, wherein a single screw is connected to one end side of each meshing screw, and the single screw is continuously connected. twin-screw extruder, characterized in that arranged at the position corresponding to the supply part of the material. Wherein the feed portion of the material into the single screw c, and characterized in that the injection hole provided on the case or the barrel at the end position corresponding communication設端opposite between the meshing screw The twin-screw extruder according to claim 1. 3. The twin-screw extruder according to claim 1 or 2, wherein the barrel is provided with a material supply site at an intermediate position in the material flow direction by the meshing screw.