Patent ID: 7001365

Claim:
A method of operating an infusion device infusing an infusing liquid into the human or animal body, the method including maintaining a constant level of said infusion liquid in a pressure control device which is in flow communication with, such as to be replenished from, a reservoir of said liquid, feeding said infusion under a constant liquid head commensurate with said constant level of said infusion liquid via a first flow line section, which is connected to a flow control device which is separate from and remote from and at a lower level to the pressure control device, dispensing by means of the flow control device the infusion liquid at a predetermined flow rate at a position correspondingly separate from, remote from and at a lower level to said constant level of said infusion liquid in said pressure control device, and conducting the infusion liquid at said predetermined flow rate, via a second flow line section to an infusion needle infusing said infusion liquid into the human or animal body.