Patent ID: 8857432

Claim:
A ventilating element for use with a breathing apparatus, the element comprising a hollow body having a closed end, an open end and a plurality of wall sections between the ends, the body defining an interior space, the wall sections being movable in an output direction toward the open end to diminish the volume of the interior space and movable in an intake direction away from the open end to increase the volume of the interior space, the element further including a fitting disposed at the open end, wherein the wall sections include a plurality of first wall sections disposed adjacent the open end, the plurality of first wall sections having a common first cross-sectional area and one or more second wall sections disposed adjacent the closed end, the one or more second wall sections having a second cross-sectional area less than the first cross-sectional area, the ventilating element further including a closed-end plate disposed at the closed end of the body and mechanically connected to one of the one or more second wall sections adjacent the closed end, whereby the wall sections can be moved by manipulating the closed end plate, and a handle mechanically connected to the closed end plate, wherein the fitting is constructed and arranged to connect the body with the breathing apparatus so that the open end of the body communicates with the breathing apparatus and so that the open end of the body is constrained against movement, and wherein the body is constructed and arranged so that without the need for an operator to select or adjust different controls, the operator can selectively either (i) manually move only the second wall sections without moving the first wall sections to pump a relatively small volume of gas per unit length of motion, or (ii) manually move the first wall sections to pump a relatively large volume of gas per unit length of motion.