Membrane assembly for a three-dimensional printing system

Abstract

A vat polymerization apparatus configured with a resin circulatory system that includes pumps arranged to extract used photo-curing resin from a tank and refresh or replace it with new resin, another fluid, or a combination of new resin and the fluid. Resin flow is regulated using a plurality of valves which are opened and closed to achieve a desired circulation process. Additional aspects of the apparatus include a membrane assembly in which a radiation-transparent flexible membrane is supported in a frame that stretches the membrane. A lip of the frame is secured to a bottom rim of the tank; thus, when the membrane assembly is in place it forms a bottom of the tank. A tension adjustment mechanism may be employed to adjust the tension of the membrane within the frame. The frame may be aligned with the tank with the aid of magnetized alignment aids distributed about the frame.

Dependencies are inferred from the claim text.