Worm press

Claim 1

A WORM PRESS FOR MELTING THERMOPLASTIC SYNTHETIC RESINS SUPPLIED IN THE FORM OF SHAVINGS, WHICH COMPRISES A HOUSING HAVING AN INLET DISPOSED TO RECEIVE THERMOPLASTIC RESIN SHAVINGS, AN INTERMEDIATE AXIAL ZONE COMMUNICATING AT ONE END WITH SAID INLET, A HEATABLE AXIAL ZONE FOR MELTING SUCH SHAVINGS, AND COMMUNICATING WITH THE OTHER END OF SAID INTERMEDIATE ZONE, AND AN OUTLET COMMUNICATING WITH SAID MELTING ZONE, FOR DISCHARGING MOLTEN THERMOPLASTIC MATERIAL THEREFROM; AND A WORM MEMBER DISPOSED FOR ROTATION WITHIN SAID HOUSING TO CONVEY SHAVINGS RECEIVED AT THE INLET THEREOF THROUGH SAID INTERMEDIATE ZONE AND INTO SAID MELTING ZONE FOR MELTING THEREIN, SAID WORM MEMBER HAVING A THREAD EXTENDING IN AXIAL LENGTH FROM SAID HOUSING INLET THROUGH SAID INTERMEDIATE ZONE AND TO SAID MELTING ZONE, SAID WORM THREAD BEING LATERALLY UNDERCUT AT AND ALONG THE ROOT PORTION THEREOF TO DEFINE A SHAVING CONVEYING REGION BETWEEN CONSECUTIVE THREAD FLIGHTS WHICH IS WIDER ALONG THE ROOT THAN ALONG THE OUTER PERIPHERY OF THE WORM MEMBER, WHEREBY A PORTION OF THE OUTWARD RADIAL COMPONENT OF SHAVING COMPACTION PRESSURE FORCES EXISTING IN SAID REGION ACTS AGAINST THE LATERALLY UNDERCUT PORTIONS OF THE THREAD THEREBY REDUCING THE PORTIONS OF SUCH RADIALLY OUTWARD PRESSURE FORCES ACTING AGAINST THE HOUSING.