An operating mechanism for a medical device comprises a photo-interrupter that can designate specified functional operations, an air-tight unit that can accommodate this photo-interrupter air-tightly, a moving member which is disposed inside the air-tight unit, and which moves between a position in which...http://www.google.com/patents/US20040171912?utm_source=gb-gplus-sharePatent US20040171912 - Operating mechanism for medical device
