A 3D printing apparatus including a tank, a print platform, a motor, a force sensor, and a controller is provided. The tank is configured to accommodate a photocurable resin. The print platform is arranged adjacent to the tank. The motor is mechanically connected to the print platform. The motor is configured to drive the print platform to move. The force sensor includes a position encoder. The controller is electrically connected to the force sensor and the motor. The controller is configured to confirm whether the print platform is configured to reach a target position through a value of the position encoder.

A radiation curable composition including at least one radiation hardenable component, a photo-initiator, and a filler material having a population of particulates in an amount greater than or equal to 50% by weight of the printable composition. The population of particulates exhibits a median diameter (D50) of greater than or equal to 0.3 micrometer on a volume-average basis as determined using the Particle Size Test Method, and the radiation curable composition exhibits a viscosity of less than or equal to 150 Pa s when measured using the Viscosity Test Method. A method, apparatus, and systems for producing composite articles by selectively exposing a portion of the radiation curable composition to a source of actinic radiation to at least partially cure the exposed portion of the radiation curable composition, thereby forming a hardened layer, preferably by an additive manufacturing process such as stereophotolithography, are also described. The composite articles may include composite dental restorations.

A radiation curable composition including at least one radiation hardenable component, a photo-initiator, and a filler material having a population of particulates in an amount greater than or equal to 50% by weight of the printable composition. The population of particulates exhibits a median diameter (D50) of greater than or equal to 0.3 micrometer on a volume-average basis as determined using the Particle Size Test Method, and the radiation curable composition exhibits a viscosity of less than or equal to 150 Pa s when measured using the Viscosity Test Method. A method, apparatus, and systems for producing composite articles by selectively exposing a portion of the radiation curable composition to a source of actinic radiation to at least partially cure the exposed portion of the radiation curable composition, thereby forming a hardened layer, preferably by an additive manufacturing process such as stereophotolithography, are also described. The composite articles may include composite dental restorations.

Systems and methods for lens creations are disclosed. The method includes initiating light transmission from a light source through a diffuser into a container holding resin and a substrate. The light transmission is performed according to an irradiation pattern wherein each point in the resin is illuminated by at least 10% of the diffuser. This causes a lens to be formed. To achieve this illumination, at least 15% of the diffuser receives light from the light source. Further, a diameter of the diffuser is greater than or equal to a diameter of the substrate. The system performing the methods includes a polymerization apparatus and may include a resin conditioning and reservoir apparatus, a metrology unit, a resin drainage apparatus and an optional postcuring apparatus.

The present disclosure provides a flow control equipment and an automatic refilling system. The flow control equipment includes: a housing, including a discharge hole in a bottom of the housing; a liquid inlet tube connecting with a top of the housing; a motor located in the housing; a flow locking blade and a plurality of flow control blades connected to the motor, where leakage holes of different sizes are formed in the flow control blades, and the motor drives the flow control blades and the flow locking blade to rotate to align the different leakage holes with the discharge hole, or to seal the discharge hole; and a liquid outlet tube connecting with the discharge hole.

The present disclosure provides a flow control equipment and an automatic refilling system. The flow control equipment includes: a housing, including a discharge hole in a bottom of the housing; a liquid inlet tube connecting with a top of the housing; a motor located in the housing; a flow locking blade and a plurality of flow control blades connected to the motor, where leakage holes of different sizes are formed in the flow control blades, and the motor drives the flow control blades and the flow locking blade to rotate to align the different leakage holes with the discharge hole, or to seal the discharge hole; and a liquid outlet tube connecting with the discharge hole.

According to one embodiment, a three-dimensional object includes a periodic structure. The periodic structure includes a plurality of unit objects which form a plurality of stepped structures connected to each other. In each of the stepped structures, the unit objects are connected together in a stepwise form along a polygonal spiral trajectory around a unit axis. In each of the stepped structures, the unit axis extends in a first direction. The stepped structures are each provided with a unit channel extending along the connected unit objects of the stepwise form. The periodic structure is provided with a channel in communication with an outside of the periodic structure, the channel including the unit channels.

According to one embodiment, a three-dimensional object includes a periodic structure. The periodic structure includes a plurality of unit objects which form a plurality of stepped structures connected to each other. In each of the stepped structures, the unit objects are connected together in a stepwise form along a polygonal spiral trajectory around a unit axis. In each of the stepped structures, the unit axis extends in a first direction. The stepped structures are each provided with a unit channel extending along the connected unit objects of the stepwise form. The periodic structure is provided with a channel in communication with an outside of the periodic structure, the channel including the unit channels.

A three-dimensional printing system includes a vertical support beam, a resin vessel assembly coupled to the vertical support beam and including a resin vessel, and a support tray positioning system. The support tray positioning system includes a support tray elevator, a lead screw nut, a motorized lead screw, an intermediate nut, and a linear bearing. The motorized lead screw engages the lead screw nut to raise and lower the support tray elevator. The linear bearing constrains motion of the support tray elevator to vertical motion. The support tray elevator, the intermediate nut, and the lead screw nut interlock to constrain rotational motion of the lead screw nut with respect to the support tray elevator while allowing for two dimensional lateral motion of the lead screw nut with respect to the support tray elevator to accommodate mechanical tolerances of the lead screw with respect to the linear bearing.

A three-dimensional printing system includes a vertical support beam, a resin vessel assembly coupled to the vertical support beam and including a resin vessel, and a support tray positioning system. The support tray positioning system includes a support tray elevator, a lead screw nut, a motorized lead screw, an intermediate nut, and a linear bearing. The motorized lead screw engages the lead screw nut to raise and lower the support tray elevator. The linear bearing constrains motion of the support tray elevator to vertical motion. The support tray elevator, the intermediate nut, and the lead screw nut interlock to constrain rotational motion of the lead screw nut with respect to the support tray elevator while allowing for two dimensional lateral motion of the lead screw nut with respect to the support tray elevator to accommodate mechanical tolerances of the lead screw with respect to the linear bearing.