Dual worm extruder having wear resistant bore walls
AssigneeFirma Friedrich Theysohn
InventorFriedrich Theysohn
Life of this patent
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Abstract
A dual worm extruder includes a worm housing having a cavity and a wear resistant insert accommodated in the cavity. The insert has two parallel extruder bores defining, when viewed together in cross section, passages of circular areas having an overlap. The outer surface portions of the insert situated on opposite sides adjacent the overlap are peripherally concave, whereby the cross-sectional outline of the insert has the shape of an hourglass.
Claims6
In a dual worm extruder including a worm housing having an inner wall defining a cavity;
- and a wear resistant insert accommodated in said cavity;
- said insert having two parallel extruder bores defining, when viewed together in cross section, passages of circular areas having an overlap;
- said insert having an outer surface formed of first surface parts facing first portions of said inner wall and being situtated on opposite sides of said insert in zones adjacent said overlap and second surface parts facing second portions of said inner wall and being situated peripherally adjacent said first surface parts of said insert;
- the improvement wherein said first surface parts are peripherally concave, whereby the cross-sectional outline of said insert has the shape of an hourglass;
- further wherein said first portions of said inner wall define a clearance with respective said first surface parts of said insert and further wherein a flowable metal fills at least one said clearance.
In a dual worm extruder including a worm housing having an inner wall defining a cavity;
- and a wear resistant insert accommodated in said cavity;
- said insert having two parallel extruder bores defining, when viewed together in cross section, passages of circular areas having an overlap;
- said insert having an outer surface formed of first surface parts facing first portions of said inner wall and being situated on opposite sides of said insert in zones adjacent said overlap and second surface parts facing second portions of said inner wall and being situated peripherally adjacent said first surface parts of said insert;
- the improvement wherein said first surface parts are peripherally concave, whereby the cross-sectional outline of said insert has the shape of an hourglass;
- further wherein said first portions of said inner wall define a clearance with respective said first surface parts of said insert;
- and further wherein a metal filler body is disposed in at least one said clearance.
Dependencies are inferred from the claim text.