Research On The Online Inspection System Of Quality Of Precision Plastic Injection Molding Products

Precision injection molding products are widely used in various industries, which play an increasingly important role in domestic industry. Small module plastic gears are typical representative of precision injection molding products, which design, manufacturing, testing get more and more attention. Small module plastic gears are generally large-scale automated production. Production technology and conditions are limited, so there are a variety of product defects, such as dissatisfaction, joint flash, burrs, etc.. These defective products can’t be allowed to flow into the market. Now the main applied inspection and recognition of defects is under human eyes. Due to gear itself complex shapes, high recognition accuracy, the human eye recognition have a higher requirements of recognition ability and endurance so gear manual inspection is time-consuming, low efficiency.A non-contact measurement system based on HALCON software is developed. According to the small module plastic gear structure and the specific testing requirements, select the appropriate illumination, industrial cameras, lenses, frame grabbers and other visual system hardware, by setting the appropriate resolution、exposure rate、image format and taking so many image acquisition by the high-speed industrial camera, the image’s contrast significantly and features clearly, which fully reflects the small modulus plastic gear inner hole, tooth profile and other characteristics. Using HALCON software in the PC for image de-noising、smoothing、segmentation、feature profile optimization、extraction、computing operations、and precise calibration of the camera system, measure the inner hole size, number of teeth, tooth pitch again and again, So far the hardware and software had allowed we reached up to 10 micron level precision measurement. Experimental results were compared and analyzed, based on the existing experimental conditions, we modified our experiment parameters to reach more and more accurate result, simulated environment of the practical scene to guide the actual production and improve productivity.