Patent ID: 8286505

Claim:
A system for controlling fluid flow that is delivered through a fluid line that enters a patient, the system comprising: a reduced cross-section orifice situated adjacent a point of entry of a fluid line into said patient; a differential force sensor including: a first force sensor; a second force sensor positioned adjacent the first force sensor; wherein said first force sensor is responsive to movement of a first flow diaphragm that is exposed to a first pressure in said fluid line upstream of the reduced cross-section orifice, and said second force sensor is responsive to movement of a second flow diaphragm that is exposed to a second pressure in the fluid line downstream of the reduced cross-section orifice; a first plunger associated with the first force sensor, wherein a first force exerted by movement of said first flow diaphragm in response to said first pressure is transferred to said first force sensor through said first plunger; a second plunger associated with the second force sensor, wherein a second force exerted by movement of said second flow diaphragm in response to said second pressure is transferred to said second force sensor through said second plunger; and said first force sensor and said second force sensor providing one or more sensor output signals; a flow controller that controls a rate of flow of said fluid through said fluid line; and one or more electronic devices, the one or more electronic devices responding to said one or more sensor output signals of said first force sensor and said second force sensor and providing one or more feedback signals to said flow controller, in a closed-loop manner, such that the flow controller actively controls the rate of flow of said fluid through said fluid line and into said patient.