3D Automatic nondestructive testing system for 3D printers using ultrasonic flaw detection method

The present invention provides an automatic nondestructive testing system for a 3D printer using an ultrasonic flaw detection method. The automatic nondestructive testing system for a 3D printer comprises: a head unit three-dimensionally printing an object; a worktable allowing the object to be three-dimensionally printed thereon; a work position adjustment unit moving the worktable to adjust the printing position of the object; a surface pretreatment means including a bead removal unit removing beads from the surface of the welding layer of the object to determine whether there are any defects before performing ultrasonic flaw detection, and a chip removal unit removing chips generated during a bead removal process; and an ultrasonic inspection unit inspecting whether there are any defects in the object printed on the worktable by using ultrasonic waves. The ultrasonic inspection unit includes: an ultrasonic probe emitting ultrasonic waves at the object to probe the object; a contact medium supply unit supplying a contact medium to the object; a contact medium application unit scraping the supplied contact medium to evenly apply the same to a thickness; a contact medium removal unit removing the contact medium remaining on an inspection surface after the probing is completed by the ultrasonic probe; a defect analysis means analyzing a signal received from the ultrasonic probe to determine discontinuous parts; and a defect repair means repairing the discontinuous parts depending on a result analyzed by the defect analysis means. Therefore, the automatic nondestructive testing system for a 3D printer can perform automatic nondestructive testing for 3D printing work inspection, of which a series of processes such as quality inspection and maintenance work can be performed by one worker and which prevents a non-destructive inspector from being directly put into a work space, thereby increasing work safety, and can automatically conduct an inspection, thereby increasing the reliability of the inspection. 본 발명은, 대상물을 3D프린팅하기 위한 헤드부; 대상물이 3D프린팅되기 위한 작업대; 상기 작업대를 이동시켜 대상물의 프린팅 위치를 조절하기 위한 작업위치조절부; 초음파탐상을 수행하기 전에 결함여부를 파악하기 위해 대상물의 용접층 표면의 비드를 제거하기 위한 비드제거부, 및 비드제거과정에서 발생된 칩을 제거하는 칩제거부를 포함하는 표면전처리수단; 및 초음파를 이용하여 상기 작업대에서 프린팅되는 대상물의 불량여부를 검사하기 위한 초음파검사부를 포함하고, 상기 초음파검사부는, 대상물로 초음파를 조사하여 탐촉하기 위한 초음파탐촉자; 상기 대상물로 접촉매질을 공급하기 위한 접촉매질공급부; 공급된 접촉매질을 스크레이핑하여 일정 두께로 고르게 도포시키기 위한 접촉매질도포부; 상기 초음파탐촉자에 의해 탐촉과정이 종료된 후 검사면에 잔류하는 접촉매질을 제거하기 위한 접촉매질제거부; 상기 초음파탐촉자에서 수신된 신호를 분석하여 불연속