Rotary pump driven medicament delivery device

A medicament delivery device comprising:

• a) a housing having an inlet connected to a reservoir of medicament and an outlet connected to a discharge device, where the housing has a back plate having an inner surface;
• b) a rotor housing positioned adjacent to the back plate;
• c) a rotor rotationally fixed to an eccentric shaft and movably positioned within rotor housing, the rotor comprising three lobes, where each lobe has two peripheral curved surfaces sharing a common apex, where a first portion of each peripheral surface adjacent to the apex defines a non-smooth curve;
• and
• d) a motor connected to the eccentric shaft to rotate the eccentric shaft during medicament delivery, where medicament is drawn into a chamber from the reservoir in the rotor housing through the inlet as the rotor turns relative to the rotor housing and the medicament is expelled through the outlet and into the discharge device.