# US 7,608,061 B2 · Flow restrictor device for a medical apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,061 B2 - Document ID: US7608061B2 - Status: Granted - Kind: B2 - Application number: 10/909,752 - Filed: 2004-08-02 - Published: 2005-09-08 - Granted: 2009-10-27 - Earliest claimed: 2004-03-02 - Inventors: Robert G. Schinazi; Lauren E. de Rosset - Web page: https://patentgrep.com/patent/US7608061B2 ## CPC - A61M 5/141: {with capillaries for restricting fluid flow} - A61M 5/168: Means for controlling media flow to the body or for metering media to the body, e.g. drip meters, counters - A61M 5/16813: {by controlling the degree of opening of the flow line} - A61M 5/16881: {Regulating valves} - G05D 7/0186: {without moving parts} - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES ## Abstract A medical apparatus flow restrictor includes a housing having an inlet housing member defining an inlet and a separate outlet housing member mated with said inlet housing member and defining an outlet from the flow restrictor. A fluid path is defined through the housing members between the inlet and outlet. Opposed flow restriction surfaces are defined between at a location along the fluid path such that fluid delivered to the inlet passes between the opposed flow restriction surfaces prior to flowing from the outlet. The opposed flow restriction surfaces have a relative degree of surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through the restrictor. ## Claims ### Claim 1 A medical apparatus flow restrictor, comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing surfaces of said inlet and outlet housing members, said flow restriction surfaces contacting each other intermittently at a plurality of locations along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; and wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor. ### Claim 2 (depends on 1) The restrictor as in claim 1, wherein a first of said opposed flow restriction surfaces is formed as an integral surface on said inlet housing member, and a second of said opposed flow restriction surfaces in formed as an integral surface of said outlet housing member. ### Claim 3 (depends on 2) The restrictor as in claim 2, wherein one of said first or second opposed flow restriction surfaces is formed in a recess, and the other of said respective second or first flow restriction surface is formed on a protrusion that extends into said recess. ### Claim 4 (depends on 3) The restrictor as in claim 3, wherein a forward portion of said inlet housing member defines said protrusion, and said recess is defined in said outlet housing member. ### Claim 5 (depends on 3) The restrictor as in claim 3, wherein said protrusion comprises a generally semi-spherical configuration, and said recess comprises a corresponding semi-spherical configuration. ### Claim 6 (depends on 3) The restrictor as in claim 3, wherein said protrusion comprises a generally flat planar surface, and said recess comprises a corresponding flat planar surface. ### Claim 7 (depends on 3) The restrictor as in claim 3, wherein said inlet housing member is pressed into mating configuration with said outlet housing member such that said opposed flow restriction surfaces are pressed together to a predetermined degree sufficient for providing a desired fluid flow through said restrictor. ### Claim 8 (depends on 1) The restrictor as in claim 1, further comprising a seal disposed between said inlet and outlet housing members to ensure that fluid flow through said restrictor is directed between said opposed flow restriction surfaces. ### Claim 9 (depends on 1) The restrictor as in claim 1, wherein said inlet and outlet housing members are permanently and non-separably joined. ### Claim 10 (depends on 1) The restrictor as in claim 1, wherein a plane between said opposed flow restriction surfaces is generally perpendicular to an axis of said inlet and said outlet. ### Claim 11 (depends on 1) The restrictor as in claim 1, wherein a plane between said opposed flow restriction surfaces is a generally curved plane with respect to an axis of said inlet and said outlet. ### Claim 12 (depends on 1) The restrictor as in claim 1, wherein said inlet and said outlet are connectable to tubing in fluid delivery system such that said restrictor is placeable in-line within said system. ### Claim 13 (depends on 1) The restrictor as in claim 1, wherein said surface roughness of at least one of said opposed flow restriction surfaces is defined in any one or combination of a controlled grinding, lapping, tumbling, sandblasting, or etching process. ### Claim 14 (depends on 1) The restrictor as in claim 1, wherein said inlet and outlet housing members are molded components, and said surface roughness of said opposed flow restriction surfaces are molded surfaces. ### Claim 15 A medical apparatus flow restrictor, comprising: an inlet housing member defining an inlet to said flow restrictor and further defining a forward portion, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor and further defining a recess; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing surfaces of said inlet and outlet housing members, said flow restriction surfaces contacting each other intermittently at a plurality of locations along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor; and wherein said forward portion of said inlet housing member comprises a tapered conical configuration, and said recess of said outlet housing member comprises a corresponding tapered conical configuration. ### Claim 16 A medical apparatus flow restrictor, comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing contacting surfaces of said inlet and outlet housing members at a location along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor; wherein said inlet housing member is pressed into mating configuration with said outlet housing member such that said opposed flow restriction surfaces are pressed together to a predetermined degree sufficient for providing a desired fluid flow through said restrictor; and wherein at least one of said opposed flow restriction surfaces is formed of a compressible material such that fluid flow between said opposed flow restriction surfaces is varied by varying a compressive pressure applied to said inlet and outlet housing members. ### Claim 17 (depends on 16) The restrictor as in claim 16, wherein each of said opposed flow restriction surfaces is formed of a compressible material such that fluid flow between said opposed flow restriction surfaces is varied by varying a compressive pressure applied to said inlet and outlet housing members. ### Claim 18 (depends on 17) The restrictor as in claim 17, wherein said compressible material is a medical grade polymer material. ### Claim 19 (depends on 18) The restrictor as in claim 18, wherein said inlet and outlet housing members are formed entirely of said polymer material. ### Claim 20 A medical apparatus flow restrictor, comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing contacting surfaces of said inlet and outlet housing members at a location along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor; and wherein a plane between said opposed flow restriction surfaces is a generally conical plane with respect to an axis of said inlet and said outlet. ### Claim 21 A medical apparatus flow restrictor, comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing surfaces of said inlet and outlet housing members, said flow restriction surfaces contacting each other intermittently at a plurality of locations along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor; and wherein one of said opposed flow restriction surfaces comprises a rougher surface as compared to said other flow restriction surface. ### Claim 22 A medical fluid delivery system configured to deliver a fluid from a source to a patient at a regulated flow rate, said system comprising delivery tubing and a flow restrictor placed in-line in said tubing, said flow restrictor further comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing surfaces of said inlet and outlet housing members, said flow restriction surfaces contacting each other intermittently at a plurality of locations along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor. ### Claim 23 (depends on 22) The fluid delivery system as in claim 22, wherein said flow restrictor is disconnectable from said tubing. ### Claim 24 (depends on 22) The fluid delivery system as in claim 22, wherein a first of said opposed flow restriction surfaces is formed as an integral surface on said inlet housing member, and a second of said opposed flow restriction surfaces is formed as an integral surface of said outlet housing member. ### Claim 25 (depends on 24) The fluid delivery system as in claim 24, wherein a forward portion of said inlet housing member is received within a recess defined in said outlet housing member, said first opposed flow restriction surface formed on said forward portion of said inlet housing member, and said second opposed flow restriction surface formed in said recess of said outlet housing member. ### Claim 26 A medical fluid delivery system configured to deliver a fluid from a source to a patient at a regulated flow rate, said system comprising delivery tubing and a flow restrictor placed in-line in said tubing, said flow restrictor further comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing contacting surfaces of said inlet and outlet housing members at a location along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor; wherein a first of said opposed flow restriction surfaces is formed as an integral surface on said inlet housing member, and a second of said opposed flow restriction surfaces is formed as an integral surface of said outlet housing member; wherein a forward portion of said inlet housing member is received within a recess defined in said outlet housing member, said first opposed flow restriction surface formed on said forward portion of said inlet housing member, and said second opposed flow restriction surface formed in said recess of said outlet housing member; and wherein said forward portion of said inlet housing member comprises a tapered conical configuration, and said recess of said outlet housing member comprises a corresponding tapered conical configuration. ### Claim 27 (depends on 26) The fluid delivery system as in claim 26, wherein said inlet housing member is pressed into mating configuration with said outlet housing member such that said opposed flow restriction surfaces are pressed together to a predetermined degree sufficient for providing a desired fluid flow through said restrictor. ### Claim 28 A medical fluid delivery system configured to deliver a fluid from a source to a patient at a regulated flow rate, said system comprising delivery tubing and a flow restrictor placed in-line in said tubing, said flow restrictor further comprising: an inlet housing member defining an inlet to said flow restrictor, and a separate outlet housing member mated with said inlet housing member and defining an outlet from said flow restrictor; a fluid path defined through said inlet and outlet housing members between said inlet and said outlet; flow restriction surfaces defined on opposing contacting surfaces of said inlet and outlet housing members at a location along said fluid path such that fluid delivered to said inlet passes between said opposed flow restriction surfaces of said inlet and outlet housing members prior to flowing from said outlet; wherein said opposed flow restriction surfaces have a random surface roughness and opposed surface area defined as a function of a desired flow rate of fluid through said restrictor, said opposed flow restriction surfaces defining a flow field of random surface contours to restrict and regulate fluid flow through said restrictor; and wherein each of said opposed flow restriction surfaces is formed of a compressible material such that fluid flow between said opposed flow restriction surfaces is varied by varying a compressive pressure applied to said inlet and outlet housing members. ### Claim 29 (depends on 28) The fluid delivery system as in claim 28, wherein said compressible material is a medical grade polymer material. ### Claim 30 (depends on 29) The fluid delivery system as in claim 29, wherein said inlet and outlet housing members are formed entirely of said polymer material.