A BOTTOM-UP 3D PRINTER, A PLATFORM FOR THIS PRINTER, AND A METHOD OF 3D PRINTING

A bottom-up 3D printer comprises a resin tub (8) provided with a quartz glass window (10), an optical system (28) comprising a laser (16) and an oscillating and/or rotating mirror (17), a platform (3) supporting on its bottom conical surface (4) the printed object (29), and the actuators (25, 26, 27) controlled by a control system, all mounted on a frame (30) enclosed in a housing. The platform (3) is suspended in a platform head (2) mounted in a suspension mechanism (1). The platform head (2) rotates about vertical axis (R1), while the platform (3) counter-rotates about inclined axis (R2) forming an angle (γ) with vertical. The axis of the cone of the platform (3) is collinear with its axis of rotation (R2), and a generatrix of the cone makes the same angle (γ) with the plane perpendicular to the cone axis. Angular velocities (ω1, ω2) of, respectively, the platform head (2) and the platform (3) are comprised in a range of 1-30 RPM, preferably 10-15 RPM. The suspension mechanism (1) has the means for radial displacement of the platform head (2) and its vertical axis (R1), relative to the point of intersection (S) of the inclined axis (R2) with the upper surface of the window (10). This point of intersection (S) remains fixed during printing. The angle (γ) is controllable by rotation of the platform (3) about a horizontal axis (R3) in the platform head (2). The platform (3) has a removable conical cap (5) fixed with the fastening means (6) to a support of the cap (7). An instantaneous position of the laser light spot (19) on the upper surface of the window (10) is controlled by a control system, through rotation or oscillation of the mirror (17) about horizontal axis (R4), and also rotation or oscillation about vertical axis (R5). UV or VIS laser light initiates the photocuring of the resin and build-up of new layer of the printout.