Spring driven infusion pump

摘要

An implantable infusion pump (20) for infusing drugs or other chemicals or solutions into the body. A flexible spring diaphragm (25) forms an outer back wall portion (26) of a housing (22) of the infusion pump (20). The spring diaphragm (25) applies substantially constant force over a range of displacement and communicating internal body pressure to the drug chamber (30) so as to maintain a substantially uniform pressure difference between the drug chamber (30) and the internal body pressure.