A drug pump is disclosed having at least one rotatable cam and a reciprocally mounted follower engaged with the cam, and a tube which is compressed by the follower during rotation of the cam. The drug pump preferably has three followers, including an expulsor follower, an inlet valve follower, and an...http://www.google.ca/patents/US5364242?utm_source=gb-gplus-sharePatent US5364242 - Pump apparatus and method including double activation pump apparatus
