Volume limiting chamber
AssigneeUnited States Surgical Corporation
InventorDouglas G. Noiles
Life of this patent
Estimating the term…
Abstract
An intravenous set has a volume limiting chamber for precisely controlling the volume of parenteral solution administered to a patient and a flexible drip chamber for determining the parenteral solution flow rate. The volume limiting chamber has a membrane valve which when wet will pass parenteral solution but will not pass air at normal intravenous administration pressures. An air bypass is provided in the volume limiting chamber so that air can bypass the membrane valve and enter the volume limiting chamber from the drip chamber when the drip chamber is squeezed to prime the intravenous set. A pressure pad insures that the membrane value is maintained in sealed contact with its seat under conditions of zero pressure drop across the membrane value but allows the wet membrane to be unseated when the drip chamber is squeezed.
Claims23
A volume limiting chamber for use in an intravenous set comprising a chamber having a top and a bottom and side walls connecting said top and bottom, an inlet passageway in said top for placing said chamber in fluid communication with a source of parenteral solution, an outlet passageway in said bottom for placing said chamber in fluid communication with an intravenous needle, indicia on said chamber for indicating the amount of parenteral solution in said chamber, a membrane valve positioned in said chamber and cooperating with said outlet fluid passageway so that all parenteral solution in said chamber flows through said membrane valve, said membrane valve comprising a material which when wet will pass parenteral fluid but will not pass air at normal intravenous administration pressures, and means for bypassing said membrane valve and allowing air to enter said chamber through said bottom from underneath said membrane valve when said membrane valve is wet, said bypass means comprising means for mounting said membrane valve in said bottom so that air can enter said volume limiting chamber around the periphery of said membrane valve, said mounting means comprising a surface against which said membrane valve is adapted to seat, said surface having a plurality of air passages formed therein in communication with said outlet passageway such that air forced through said outlet passageway and said air passages will act to unseat said membrane valve, said mounting means further comprising a bypass member spaced from said surface to define a membrane valve chamber therebetween, said membrane valve being mounted in said membrane valve chamber adjacent said surface, said bypass means further comprising a pressure pad mounted in said membrane valve chamber between said membrane valve and said bypass member whereby said membrane valve is resiliently urged into contact with said surface by said pressure pad.
An intravenous set comprising a volume limting chamber for controlling the volume of parenteral solution administered to a patient and a flexible drip chamber for determining the parenteral solution flow rate positioned downstream of said volume limiting chamber, said volume limiting chamber including a top and bottom and side walls connecting said top and bottom, an inlet passageway in said top for placing said volume limiting chamber in fluid communication with a source of parenteral solution, an outlet passageway in said bottom for placing said volume limiting chamber in fluid communication with said drip chamber, indicia on said volume limiting chamber for indicating the amount of parenteral solution in said volume limiting chamber, a membrane valve positioned in said bottom of said volume limiting chamber parenteral solution in said volume limiting chamber flows and cooperating with said outlet passageway so that all through said membrane valve, said membrane valve comprising a material which when wet will pass parenteral solution but will not pass air at normal intravenous administration pressures, and means for bypassing said membrane valve and allowing air to enter said volume limiting chamber from said drip chamber when said membrane valve is wet and said drip chamber is squeezed, said bypass means comprising means for mounting said membrane valve in said bottom so that air can enter said volume limiting chamber around the periphery of said membrane valve, said mounting means comprising a surface against which said membrane valve is adapted to seat, said surface having a plurality of air passages formed therein in communication with said outlet passageway such that air forced through said outlet passageway, and said air passages will act to unseat said membrane valve, said mounting means further comprising a bypass member spaced from said surface to define a membrane valve chamber therebetween, said membrane valve being mounted in said membrane valve chamber adjacent said surface, said bypass means further comprising a pressure pad mounted in said membrane valve chamber between said membrane valve and said bypass member whereby said membrane valve is resiliently urged into contact with said surface by said pressure pad.
A valve for use in an intravenous set comprising a membrane which when wet will pass parenteral fluid but will not pass air at normal intravenous administration pressures and means for mounting said membrane so that air can bypass said membrane when wet, said mounting means comprising a surface against which said membrane is adapted to seat with an airtight seal, said surface having air passage means formed therein such that air forced through said air passage means will unseat said membrane, said mounting means further comprising means for restraining the movement of said membrane when unseated, said restraining means comprising a resilient pressure pad.
A filter for use in an intravenous set comprising a membrane which will filter parenteral fluid and means for housing said membrane including a surface against which said membrane when wet is adapted to seat with an airtight seal at normal intravenous administration pressures, said housing means further comprising means for restraining the movement of said membrane when unseated so that said membrane is confined adjacent to said surface, said membrane being unattached to said housing means, said restraining means comprising a resilient pressure pad for resiliently urging said membrane into contact with said surface.
An intravenous set comprising a volume limiting chamber for controlling the volume of parenteral solution administered to a patient and a flexible drip chamber for determining the parenteral solution flow rate positioned downstream of said volume limiting chamber, said volume limting chamber including a top and bottom and side walls connecting said top and bottom, an inlet passageway in said top for placing said volume limiting chamber in fluid communication with a source of parenteral solution, an outlet passageway in said bottom for placing said volume limiting chamber in fluid communication with said drip chamber, indicia on said volume limiting chamber for indicating the amount of parenteral solution in said volume limiting chamber, a membrane valve positioned adjacent to said outlet passageway and cooperating with said outlet passageway so that all parenteral solution in said volume limiting chamber flows through said membrane valve, said membrane valve comprising a material which when wet will pass parenteral solution but will not pass air at normal intravenous administration pressures, and means for bypassing said membrane valve and allowing air to enter said volume limiting chamber from said drip chamber when said membrane valve is wet and said drip chamber is squeezed, said bypass means comprising a resilient pressure pad for resiliently urging said membrane valve into seating engagement with said outlet passageway, said pressure pad being adapted to restrain the movement of said membrane valve when unseated so that said membrane valve is confined adjacent to said outlet passageway.
Dependencies are inferred from the claim text.