JPS59224327A - Cylinder extruder with grooved weighing section - Google Patents

Abstract

PURPOSE:To prevent uneven temperature distribution of materials by a method in which grooves are provided at right angle to the direction of thread of the screw on the inner surface of the weighing section cylinder of an extruder in such a way as to raise the mixing degree of molten resin by high extruding forces with high back pressure of the screw. CONSTITUTION:When a screw is turned counterclockwise at a speed U in relation to a cylinder, it dynamically equals the clockwise rotation of the cylinder with the speed U in relation to the screw. In short, grooves 4 are provided continuously at equal intervals at right angle to the flow direction of molten resin with component velocity V in the direction of the screw groove 2 of the speed U. Frictional coefficient between both is raised, extruding performance is raised, the mixing degree is raised, the molten resin is homogenized, the temperature rise of the resin is prevented, and the temperature distribution of the resin is equalized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the modification of a melt-kneading extruder for thermoplastic resins, etc. An extrusion-like screw consists of a feed section, which is the part near the popper, a compression part, which is the central part, and a metering part, which is the tip part, which is historically near the flaker plate. The present invention is characterized in that a groove is provided on the inner surface of one of the seven rings of the metering portion in a direction perpendicular to the direction of the screw thread groove.

The above three parts of the extruder are: feeding of resin in the feeding section, compression and plasticization of the material in the compression section, and kneading of the molten resin material and extrusion of the material against screw back pressure in the metering section. will be carried out. Conventionally, various improvements have been made to the screw in this metering section in order to obtain a high degree of kneading and a high extrusion capacity. However, as demands for diversification and higher quality of synthetic resin materials increase, these demands cannot be met by conventional improvements to the screw itself, such as improving the shape of the screw.

The purpose of this product is to overcome the above problems by increasing the screw back pressure, providing strong extrusion ability against this pressure, increasing the degree of kneading of the molten resin feathers, and
Prevents temperature unevenness of the phase material and maintains uniformity 1. (As mentioned above, the present invention has grooves perpendicular to the direction of the screw thread groove on the inner surface of the so-called weighting part unrinder. C,
A propelling force (f) is applied to the resin material parallel to the direction of the screw thread groove, and the resin moves forward along the thread groove. - Since the inner surface of the cylinder is provided with < ftf as described above, this groove applies a small force to the flow of resin, increasing the coefficient of friction between the resin and the inner wall of the cylinder, and increasing the friction coefficient at the tip of the screw. The extrusion capacity is increased by 10 to 30% compared to the conventional method by applying pressure yK higher than the back pressure to the resin. In addition, the large number of grooves on the inner surface of the cylinder allow for repeated kneading, which results in a large dispersion effect and a high degree of kneading, resulting in uniformity of kneading. Since it is made thicker, it is possible to lower the resin temperature by 1≦h and to equalize the temperature compared to the conventional one.

The groove on the inner surface of the cylinder according to the present invention is made of molten resin f11?
The shape may be arbitrary as long as it can prevent retention. Further, the grooves may be at regular intervals or at irregular intervals, and may be continuous or discontinuous.

Examples of the present invention will be described below. For comparison, FIG. 1 shows a metering section having a conventional grooveless cylinder, FIG. FIG. 3 is a developed view of the screw and the inner surface of the cylinder of the same embodiment for illustration purposes only.

If the screw rotates counterclockwise with respect to the screw at a speed U, it is mechanically equivalent to the rotation of the ring clockwise with respect to the screw at a speed U (see FIG. 6). In other words, the molten resin flows along the cylinder inner surface 1 with a component of the speed U in the direction of the screw thread groove 2 and a velocity V, while the cylinder inner surface 1 has grooves 4 continuously and at regular intervals perpendicular to the flow of the resin. It is set in. Therefore, the coefficient of friction between the two increases 9, and the above-mentioned remarkable effects such as an increase in extrusion capacity, an improvement in the degree of kneading, an equalization of ftjj, and further prevention and equalization of the resin temperature can be obtained. .

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of the metering section of the conventional example, FIG. 2 is a vertical cross-sectional view of the cylinder according to the embodiment of the present invention, and FIG. 6 is a developed view of the inner surface of the screw and syringe of the same embodiment. 1... Cylinder inner surface, 2... Screw groove, 3...
・Scrini], -flight, 4...groove. Patent π Applicant Japan Steel Works Co., Ltd. Patent attorney Yasu 1) Three generations 1; 11 Patent attorneys

Claims (1)

[Claims] An extruder characterized in that a groove is provided on the inner surface of the metering part cylinder in a direction perpendicular to the direction of the screw thread groove.