Patent ID: 8535283

Claim:
A manually-actuated pump for applying reduced pressure at a tissue site, the manually-actuated pump comprising: a casing having a top casing portion and a bottom casing portion; at least one variable volume chamber disposed within the casing that is manually compressible into a plurality of positions; a fixed volume chamber disposed within the casing and being in communication with the at least one variable volume chamber; and a filter housing disposed within the casing between the fixed volume chamber and the at least one variable volume chamber, the filter housing having a hydrophobic filter that prevents liquid from entering the at least one variable volume chamber, the fixed volume chamber having reduced pressure that is applied to the tissue site in response to a movement of the at least one variable volume chamber from a compressed position in the plurality of positions to an uncompressed position in the plurality of positions; wherein the top casing portion is configured to slide relative to the bottom casing portion as the at least one variable volume chamber moves from the compressed position to the uncompressed position.