Abstract
This pump system consists of 4 mechanism as follows. (1) Double chambered alternate pumpimg. (2) Magnet-hall IC sensor was provided between each chamber and each housing. Each solenoid valve was opened by the trigger of presetting electrical voltage. However, both valve can not open at the same time, but wait untill first come pulse finishes its action. (3) Air pressure was adjusted to minimize this delay time, because it should be no delay when the output is equal to the input. (4) Trigger point was set to minimize the negative pressure which was generated inside the pump due to the resiliency of the chamber wall itself. Results obtained in mock circulation and in animal experiment indicated that our pump system worked automatically on the Starling's law of the heart.
