| 摘要 |
<p>1,223,993. Jet pumps. W. WATSON & SONS Ltd. and J.A. BUSHMAN. May 3, 1968 [May 10, 19671, No.21755/67. Heading F1E. A bi-stable flow jet pump with reversible direction of flow, e.g. for use as a medical ventilator for passing air or gas to or from a patient, comprises an annular inlet 32 for the inducing air or gas from supply 45, the direction of flow along inlet surfaces 36 being determined by the pressure differential between connections 30 and 31, or control pressures applied to annular control passages 28 on either side of inlet 32. With atmospheric pressure in both control passages, the inducing fluid follows the right-hand surface 36 and induces flow from connection 31 to connection 30. If the control pressure at control port 14 is increased above that at control port 12, the inducing flow is re-directed to follow the left-hand surface 36, and induces flow from connection 30 to connection 31. For use as a medical ventilator, connection 30 is connected to a patient by a mask, and the control ports 12 and 14 may be connected to the patient's airway through a connecting device 46 or to a timing device for alternately blocking ports 12 and 14, to switch the direction of flow. Connection 31 is connected to a supply 43 of air, oxygen or anaesthetic gas, or to exhaust.</p> |
