Patent ID: 8303276
Filing Date: 2012-11-06
Classification: A61M,F04B

Abstract:
1. Double acting respirator pump apparatus comprising: a housing having a pump cylinder, a pump inlet port for respiratory gas supply to the pump cylinder, and a pump outlet port for delivery of pressurized respiratory gas to a patient; the pump cylinder having opposite first and second ends, and a pump member movably mounted in said cylinder and separating said cylinder into first and second pump chambers on opposite sides of said pump member between the pump member and the first end of the cylinder and the pump member and the second end of the cylinder, respectively; said pump member being reciprocable in opposite first and second directions in a reciprocation cycle with respect to said pump chambers to provide an outlet pumping stroke with respect to the first pump chamber in which respiratory gas is pumped from said first pump chamber to said outlet chamber and out of said outlet port and an inlet stroke with respect to the second pump chamber in which respiratory gas is drawn from said inlet chamber into said second pump chamber when said pump member moves in the first direction towards the first end of the cylinder, and an outlet pumping stroke with respect to the second pump chamber in which respiratory gas is pumped from said second pump chamber to said outlet chamber and out of said outlet port and an inlet stroke with respect to said first pump chamber in which respiratory gas is drawn from said inlet chamber into said first pump chamber when said pump member moves in the second direction towards the second end of said cylinder; wherein said inlet stroke and said outlet stroke for each pump chamber defines for the respective pump chamber a displacement volume that is displaced in the respective pump chamber by reciprocation of the pump member in one reciprocation cycle between the respective inlet stroke and the respective outlet pumping stroke, and wherein a volume of at least one said pump chamber at the end of the respective said outlet pumping stroke thereof is a first proportion of the respective said displacement volume, wherein said first proportion is not less than about 50%, and wherein said pump member comprises a piston reciprocably mounted with respect to said pump chambers via a convolution diaphragm configured to support and guide the pump member in axial reciprocating movement in said opposite first and second directions in said cylinder, the diaphragm being peripherally joined to the piston and anchored with respect to said cylinder, and wherein said diaphragm is configured for avoiding being collapsed during the outlet pumping stroke of each said pump chamber.