SU937173A2 - Plastisizer meter for thermosetting moulding materials - Google Patents

Description

(54) BATCH-PLASTICATOR FOR THERMO-REACTIVE PRESS MATERIALS

one

The invention relates to polymer engineering and can be used for dosing and pre-kneading before pressing thermosetting plastics.

According to the main author. St. No. 686887 is known a kneader-kneader for thermosetting press materials containing a material Cylinder and a screw with an ejector moving coaxially in it in an axial direction, the dispenser being provided with a drive plunger coaxially screwed in the material cylinder to counter the displacement of the press material 1.

A disadvantage of the known plasticizer-dispenser is its limited technological capabilities, since it does not provide for fast readjustment to receive doses that differ from a circle, for example square, hexagonal, oval, etc., which is necessary to reduce the compression part of the mold. In addition, the performance of a known plasticizer, depending on the length of the dose and its cross section, is limited, since the dose cross section does not exceed the diameter and must fit (in the case of a dose cross section in the form of a square, hexahedron, etc.) into the cross section of the material cylinder, which leads to a sharp increase in the flow resistance of the material, i.e. a decrease in productivity, while the length of the dose cannot be increased by more than acceptable values.

The purpose of the invention is the expansion of technological capabilities by increasing the range of doses and improving the performance of the plasticizer batcher.

This goal is achieved by the fact that the kneader-kneader for thermosetting press materials is provided with a liner installed in the material cylinder and enclosing the drive plunger with a shaping working surface, the ratio of the cross-sectional areas of the insert and the material cylinder being between 1.01 and 1.25.

Claims (2)

In addition, the transition from the material cylinder to the shaping working surface of the liner is made according to a hyperboloid of rotation, which helps to increase the quality of the cylindrical shape. The presence of a liner with a shaping working surface of various cross sections helps to obtain doses of various shapes during a quick changeover of the batcher-platikator, since the installation of the insert from the end portion of the material cylinder is a simple process. The ratio of the cross-sectional areas of the liner and the material cylinder creates the conditions for the best filling of the liner with the material. Making the transition between the material cylinder and the liner along the hyperboloid of rotation also provides high-quality filling of the liner with the material in the case of making doses of a cylindrical shape. FIG. 1 shows a plasticizer dispenser, general view; in fig. 2 - insert cross-sectional shapes. The plasticizer batcher consists of a press material loading mechanism 1, a material cylinder 2, a screw 3 -c located inside it, a rotary actuator 4 and an extractor 5 that is coaxially mounted in the axially moving dose ejector 5, a quick-release liner 6 with a shaping working surface. creating a counter-pressure to the movement of the press material with the plunger 8 installed in the liner 6, and the device 9 to maintain the required temperature of the zone of softening of the material cylinder 2. The ratio of the areas of transverse cross-section the inlays of liner 6 and material cylinder 2 are selected within 1,, 25 to ensure the conditions for the best filling of liner 6 with press material and confirmed by tests that showed that with an increase in the ratio of cross sections over 1.25 (during the test, 20 doses were made each ratios) the dose dispersion increases and their quality deteriorates due to the appearance of chipping caused by the uneven density of the press material. The transition 10 from the material cylinder 2 to the shaping working surface of the liner 6 is made according to a hyperboloid of rotation when manufacturing doses of a cylindrical shape. The optimality of the proposed solution is also confirmed by experiments, which showed that a transition along a conical surface does not ensure sufficient mixing of the press material and the removal of volatile components, which complicates the conditions for pressing parts from these doses (the number of prepressions increases and the pressing time increases) and provides a transition 10 along the hyperboloid of rotation intensive movement of the press material, contributing to the removal of volatile and increase the quality of cylindrical doses. Dispenser-plasticizer works as follows. From the loading mechanism 1, the press material enters the material cylinder 2, is caught by the turns of the screw 3 receiving rotation from the actuator 4, and moves towards the liner b of the forming / heating zone against the walls of the material cylinder 2 whose temperature is maintained by device 9. In zone shaping the liner 6, there is a counter-pressure plunger 8 in the press material, coupled to the actuator 7 with adjustable force. When moving, the press material fills the expanding part of the forming zone of the liner 6, the plunger 8 moves away from the screw 3, maintaining the required density of the press material in the filling zone, and after the dose is set, the ejector 5 pushes it out. After that, the plunger 8 returns to its original position and the operation is repeated. The use of the proposed Plastic Dispenser allows to expand the range of doses, improve their quality and increase the productivity of the plasticizer. Claim 1. Batch plasticizer for thermosetting press materials according to ed. St. No. 686887, characterized in that, in order to expand technological capabilities by increasing the range of doses and improving the performance of the plasticizer dispenser, it is provided with a liner with a shaping working surface installed in the material cylinder and covering the drive plunger Chindra selected in the range of 1.01-1.25. 2. A plasticizer dispenser according to claim 1, characterized in that, in order to improve the quality of the cylindrical dose, the transition from the material cylinder to the forming working surface of the liner is made along a hyperboloid of rotation. Sources of information taken into account during the examination 1. USSR author's certificate No. 686887, cl. B 29 B 1/032, 1977 (prototype). f JO FIG. 2