A syringe for administering medicines, pharmaceuticals, and other liquid or semi-liquid materials includes a movable scale which is automatically reset to a zero position after a preselected dosage of material has been discharged from the syringe. The scale is adjustable for selecting subsequent dosages...http://www.google.com.tw/patents/US5328486?utm_source=gb-gplus-share專利 US5328486 - Syringe for dispensing multiple dosages
