Apparatus and method of transferring, focusing and purging of powder for direct printing at low temperature

A method for transferring, focusing and purging powder for direct printing at low temperature, comprising

• a first operation of:
• accelerating and aerosolizing powder, contained in a reservoir tank connected to an operation chamber housing having an internal space maintained at a predetermined negative pressure, the reservoir tank being at a higher pressure than the operation chamber housing, using a pressure difference between an operation chamber housing side that is a low pressure side based on upper and lower portions of the reservoir tank and a bottom side of the reservoir tank that is a high pressure side in such a way that a compression wave or a shock wave resulting from collapse of the pressure difference when a pressure unit connected to the reservoir tank by a second pipe is opened is transmitted from the bottom side of the reservoir tank that is the high pressure side to the operation chamber housing side that is the low pressure side;
• transferring the aerosolized powder along an internal passage of the first pipe;
• and applying the aerosolized powder to a surface of a work target disposed in the operation chamber housing;
• a second operation of;
• using a visual recognition unit provided in the operation chamber housing to observe in real time conditions in which the powder is applied to the surface of the work target and deposited thereon;
• and transmitting a signal for interrupting the operation of the pressure unit to a controller electrically connected to the pressure unit and the visual recognition unit when work of applying the powder to the surface of the work target is completed in response to a preset value of the controller;
• and
• a third operation of transmitting an operation signal from the controller to a purging unit coupled to an end of a third pipe branching off from the second pipe when the operation of the pressure unit is interrupted, so that the purging unit returns transfer gas mixed with the aerosolized powder that has remained in the operation chamber housing and the first pipe to an outside of the reservoir tank,
• the first through third operations being repeatedly conducted, and
• the controller transmitting pulse signals to the pressure unit and the purging unit, respectively, such that interrupting the pressure unit and the operating the purging unit are conducted at the same time, and interrupting the purging unit and opening the pressure unit are conducted at the same time.