EXTRUDER Russian patent published in 1998 - IPC

FIELD: processing thermoplastic materials requiring continuous mixing and homogenizing. SUBSTANCE: extruder has case and hollow worm with mixing device arranged between its turns. Mixing device is made in the form of spring-loaded pins placed in homogenizing region of worm. Pins are installed for radial displacement in plane perpendicular to longitudinal axis of worm shaft. Camshaft coaxially installed inside worm has its cams contacting spring-loaded pins. The latter are wing- shaped in section to provide for agitating processed material moving through helical groove of worm. In addition, conical slits are made in worm turns in pressure stabilization region which are converging in direction opposing product motion. Flow section of slits increases from origin to end of region in proportion to pressure rise. Slits are arranged at certain angle to turns equal to angle of slope of helical line and spaced through pitch L over helical thread. Formula for determining pitch of conical slits is given in description of invention. EFFECT: improved quality of product due to intensified mixing process and predetermined variation of temperature conditions. 3 cl, 5 dwg