Blood filtering device

A blood filtering device comprising:

• a housing;
• a filtration section disposed in the housing;
• a first tubular variable volume blood reservoir arranged in the housing and having:
• a first piston movably arranged within the first tubular variable volume blood reservoir, the first piston movable to vary a first blood reservoir volume of the first tubular variable volume blood reservoir;
• a second tubular variable volume blood reservoir having:
• a second piston movably arranged within the second tubular variable volume blood reservoir, the second piston movable to vary a second blood reservoir volume of the second tubular variable volume blood reservoir;
• a receptacle disposed in the housing and configured to receive and fluidically connect to the second blood reservoir volume of the second tubular variable volume blood reservoir;
• a rod arranged in an interior of the first tubular variable volume blood reservoir, the rod movable relative to the housing and the first tubular variable volume blood reservoir, the rod extending along and through the first blood reservoir volume, the rod comprising:
• a first end having the first piston coupled thereon, the first piston contacting against blood in the first tubular variable volume blood reservoir;
• and
• a second end of the rod having a push button;
• a coil spring having:
• a first end pressing against the housing in which the filtration section and the first tubular variable volume blood reservoir are both arranged;
• and
• an opposite second end pressing against the push button of the rod, wherein the coil spring acts against the housing, urging the first piston to move relative to the first tubular variable volume blood reservoir and the housing, to apply pressure to blood in the first blood reservoir volume, urging the blood to flow into the filtration section;
• wherein the filtration section comprises
• a filter medium separating a raw side and a clean side from each other;
• wherein the filtration section comprises
• a first communication path fluidically connecting the raw side and the first variable blood reservoir volume to each other and further comprises
• a second communication path fluidically connecting the raw side and the receptacle to each other;
• wherein, upon variation of the first variable blood reservoir volume by the coil spring apply pressure to blood in the first blood reservoir volume, blood contained in the first variable blood reservoir volume flows through the first communication path to the raw side and blood plasma/serum of the blood passes through the filter medium from the raw side to the clean side while residual blood flows from the raw side through the second communication path into the second variable blood reservoir volume coupled to the receptacle, and,
• upon variation of the second variable blood reservoir volume coupled to the receptacle by actuation of the second piston apply pressure to blood in the second blood reservoir volume, blood contained in the second variable blood reservoir volume flows through the second communication path to the raw side and blood plasma/serum of the blood passes through the filter medium from the raw side to the clean side while residual blood flows from the raw side through the first communication path into the first variable blood reservoir volume, compressing the coil spring.