A pneumatic particulate blaster apparatus consisting of a hopper having an open top for receiving particulate material and having a lower terminus communicating with generally cylindrically configured hollow tubing, vibrating means mounted on a lower side of the hopper, auger means in the tubing for...http://www.google.com.tw/patents/US5099619?utm_source=gb-gplus-share專利 US5099619 - Pneumatic particulate blaster
