Appearance inspection machine for printed circuit board

The invention provides a testing machine used for testing the appearance of a printing circuit board, comprising a frame which is provided with a transmission mechanism; the front end of the transmission mechanism is provided with an upper plate mechanism; the transmission mechanism is internally provided with two scanning mechanisms; a panel turnover mechanism is arranged between the two scanning mechanisms; the tail part of the transmission mechanism is butt-jointed with a sorting mechanism; and all mechanisms are controlled by control host machines cooperatively. The testing machine adopts a whole-line digital camera photographing technique to detect the defects on the printing circuit such as foreign matter, exposed copper, supplemented oil, scraping, poor gold-plating, character error, non-uniform green oil, non-uniform welding disc, non-uniform depth of channel, residual copper, omitted printing, developing and the like, automatically feeds and sorts the nondefective and waster, improves the simpleness and reliability of the operation, can observe the defects of the board in real-time by adopting a powerful image processing and analysis software system to provide a plurality of image processing and analysis systems, has quick detection speed, high detection efficiency, safe and reliable equipment, simple operation, is convenient and easy to be learned and meets the man-machine interaction.