An actuator mechanism and assembly for sequentially advancing and retracting a lancet needle includes a housing having an opening for operating projection of the needle. Two guide tracks are provided within the housing for guiding separate motions of a two-part needle holder structure propelled by a...http://www.google.com.au/patents/US5527334?utm_source=gb-gplus-sharePatent US5527334 - Disposable, retractable lancet
