The present invention includes a filtration apparatus for an injection molding machine where the injection molding machine includes a screw housed within a bore for generating molten polymer. A tip member extends axially from the screw. The tip member has radially extending upstream and downstream flanges positioned axially apart from each other. A filter encircles the tip member and is capable of filtering the molten polymer. An annular ring member encircles the tip member and is slidably positioned within the bore between the upstream and downstream flanges. The ring member is capable of sliding between the flanges for directing the molten polymer through the filter or preventing back flow of the molten polymer past the upstream flange. An end stop is positioned within the bore and is capable of engaging and preventing movement of the ring member past the end stop while allowing the downstream flange of the tip member to be translated forwardly therepast to simultaneously space the upstream and downstream flanges apart from the ring member. This allows the molten polymer to bypass the filter for purging contaminants filtered from the molten polymer.

Polymer filteration apparatus and method of use

With the same screw diameter as in conventional screw
extruders, an improved device is disclosed wherein the screw
length is reduced, whereby the material residue is reduced,
the throughput is increased, the screw motive power is
reduced, the temperature control is facilitated to prevent
rubber scorching, and extrusion molding of a vulcanizable
rubber composition is made possible at a low temperature. In a composite extruding apparatus of rubber, a gear pump (20)
is connected to a tip end of a screw extruder (10) via a
screen mesh (14) having a breaker plate (15), and a die head
(24) is connected to an ejecting side of the gear pump (20),
wherein the screw extruder (10) plasticizes a fed rubber
composition (G) mainly by friction with an inner surface of a
barrel (12) and by heating from outside, and extrudes the
rubber composition (G) from the screen mesh (14) to a space on
the inlet side of the gear pump (20). The screen mesh (14)
rectifies the rubber composition (G) passing through the
screen mesh (14) towards the gear pump (20) while stirring and
plasticizing the rubber composition (G) by friction and shear.
The gear pump (20) further stirs and plasticizes the rubber
composition (G), which is fed to the space on the inlet side,
by shear and compression, and gives a forcing pressure to the
die head (24).

Composite extruding apparatus of rubber and method of extruding unvulcanized rubber

A compact and precision extrusion system and method for extruding strips of rubber compounds with profiles of accurate dimensions. Strips of rubber compound (7) are uniformly heated and mixed in an extruder and then passed through a low pressure drop strainer (19) to remove foreign matter. The strained compound then is fed directly into a gear pump (20) which delivers precise volumes of the rubber compound immediately into the spread chamber of an extrusion head (21) after which it passes through a die to form a precise strip (23) of the rubber compound. The strainer and extrusion head are movably mounted with respect to the gear pump for axial separation from the gear pump for easy removal of the rubber compound from the various components of the system to facilitate compound changes. A control system regulates the speed of the extruder to provide a near constant pressure at the entrance port of the gear pump to precisely regulate the rate of extrusion of the compound from the extrusion head. The extruder preferably includes a feed section (30), a pressure generation section (31), and a mix section (32) which maintain the temperature of the rubber compound below 100°C.

A compact precision extrusion system and method

Method and apparatus is set forth for supporting a laminated extrusion die in such a manner so as to virtually eliminate all tensile stress in the die by applying a compressive force to end portions of die blades, forming said laminated die, parallel to the neutral axis thereof and offset a given distance from the neutral axis toward an outlet face of the die.

Laminated extrusion die blade support

A filtration apparatus for use in polymer processing includes a housing having an internal bore for directing polymer flow and a channel oriented transversely to the bore. A slide plate for supporting filters is movable through the channel and across the bore. An annular upstream seal ring sealably contacts the slide plate. A surface of the upstream seal ring facing the upstream direction is angled with respect to the bore. A plurality of ring segments are arranged to form an annular segmented ring. The segmented ring presents a tapered ring surface that is generally complimentarily angled relative to the angled surface of the upstream seal ring. Pressurized polymer flowing through the bore imparts radially forces on the ring segments, causing the ring segments to impart axial forces on the upstream seal ring to enhance the seal interface between the upstream seal ring and the slide plate.

Sliding plate filter with segmented sealing ring

In a screw extrusion device used for extruding plastics materials, a filter or tool-carrier is disposed at the downstream or outlet end of the extruder, an annular pressure element bearing on the carrier so as to secure and seal the carrier in its operative position The carrier is displaceable perpendicularly to the flowpath of the plastics material so as to permit facile changing of the filter element The annular pressure element is acted upon by hydraulic fluid, the hydraulic circuit including an annular pressure chamber The inner and outer walls of the chamber are formed, respectively, by concentric metal bellows One end of each bellows is mounted on the pressure element and the other end thereof on a housing

Filter or tool-changing device for screw extruders

Sieb- oder werkzeugwechselvorrichtung fuer schneckenextruder

CHANGEUR DE TAMIS OU DE FILIERE POUR EXTRUDEUSES A VIS DE MISE EN OEUVRE DE MATIERES PLASTIQUES, AVEC UN PORTE-TAMIS OU PORTE-FILIERE MOBILE PERPENDICULAIREMENT A L'AXE DU CANAL D'ECOULEMENT ET BLOQUE AVEC ETANCHEITE DANS LA POSITION DE TRAVAIL PAR UN POUSSOIR ANNULAIRE, ALIMENTE HYDRAULIQUEMENT PAR UNE CHAMBRE DE PRESSION ANNULAIRE. LA CHAMBRE DE PRESSION ANNULAIRE 15 EST FORMEE PAR DEUX SOUFFLETS METALLIQUES 13, 14, DISPOSES CONCENTRIQUEMENT ET FIXES D'UNE PART SUR UN POUSSOIR ANNULAIRE 16 ET D'AUTRE PART SUR LE CORPS 4, 10. L'INVENTION SUPPRIME LES PROBLEMES D'ETANCHEITE DU FLUX HYDRAULIQUE DANS LA CHAMBRE DE PRESSION ANNULAIRE ET PERMET UNE COURSE SUFFISANTE DU POUSSOIR ANNULAIRE.

Herbert Adolf Dipl Ing

Papers

Filter or tool-changing device for screw extruders

Sieb- oder werkzeugwechselvorrichtung fuer schneckenextruder

Changeur de tamis ou de filiere pour extrudeuses a vis