Use of Automatic Flow Regulators for Flow Modulation During Blood Collection

Abstract

A flow regulator for a blood collection assembly includes a housing having an inlet and an outlet, which defines an interior space between the inlet and the outlet. A membrane having a first surface and a second surface is disposed at least partially within the interior space. The membrane has a first position where a flow path between the inlet and the outlet is substantially open, and a second position where the flow path between the inlet and the outlet is at least partially restricted. The membrane is configured to move between the first and second positions in response to a pressure differential acting on the membrane.

What is claimed is: 
     
         1 . A flow regulator for a blood collection assembly comprising:
 a housing having an inlet and an outlet and defining an interior space between the inlet and the outlet; and   a membrane having a first surface and a second surface disposed at least partially within the interior space, the membrane having a first position wherein a flow path between the inlet and the outlet is substantially open, and a second position wherein the flow path between the inlet and the outlet is at least partially restricted, the membrane configured to move between the first and second positions in response to a pressure differential acting on the membrane, wherein the membrane comprises a body defining an opening therethrough and a valve member extending from the body towards the outlet of the housing, and wherein the valve member is advanced at least partially into the outlet to at least partially restrict the flow path when the membrane is in the second position.   
     
     
         2 . The flow regulator of  claim 1 , wherein the pressure differential is generated by a first pressure acting on the first surface of the membrane and a second pressure acting on the second surface of the membrane, the first pressure greater than the second pressure. 
     
     
         3 . The flow regulator of  claim 1 , wherein the inlet of the housing comprises one of a male luer fitting and a female luer fitting, and wherein the outlet of the housing comprises the other of the male luer fitting and the female luer fitting. 
     
     
         4 . The flow regulator of  claim 1 , wherein the membrane has an opening defined within the membrane in fluid communication with the inlet and the outlet. 
     
     
         5 . The flow regulator of  claim 4 , wherein the opening comprises a plurality of openings radially spaced from the projection. 
     
     
         6 . The flow regulator of  claim 5 , wherein the membrane further comprises a plurality of flexible tabs disposed between the plurality of openings. 
     
     
         7 . The flow regulator of  claim 4 , wherein the projection has a frusto-conical shape. 
     
     
         8 . The flow regulator of  claim 7 , wherein the housing includes a tapered portion having a shape substantially corresponding to the frusto-conical shaped projection, and wherein a distance between the tapered portion of the housing and an outer surface of the frusto-conical shaped projection is smaller when the membrane is in the second position than when the membrane is in the first position. 
     
     
         9 . The flow regulator of  claim 7 , wherein a portion of the frusto-conical shaped projection is positioned adjacent to the housing to at least partially restrict the flow path extending between the inlet and the outlet of the housing when the membrane is in the second position. 
     
     
         10 . The flow regulator of  claim 4 , wherein the inlet of the housing comprises one of a male luer fitting and a female luer fitting, and wherein the outlet of the housing comprises the other of the male luer fitting and the female luer fitting. 
     
     
         11 . The flow regulator of  claim 4 , wherein the membrane is secured to the housing by a plurality of flexible tabs. 
     
     
         12 . The flow regulator of  claim 1 , wherein the membrane is configured to move between the first and second positions based on a pressure differential acting on the first surface and the second surface of the membrane. 
     
     
         13 . The flow regulator of  claim 1 , wherein the housing comprises first and second portions, and wherein a perimeter of the membrane is secured between the first and second portions of the housing. 
     
     
         14 . The flow regulator of  claim 1 , wherein a body of the valve member includes a tapered portion with a truncated profile adjacent the outlet. 
     
     
         15 . The flow regulator of  claim 1 , wherein the inlet of the housing comprises one of a male luer fitting and a female luer fitting, and wherein the outlet of the housing comprises the other of the male luer fitting and the female luer fitting. 
     
     
         16 . The flow regulator of  claim 1 , wherein the membrane comprises a body having a convex surface and a concave surface, the membrane configured to move between the first and second positions based on a pressure differential acting on the convex surface and the concave surface of the body of the membrane. 
     
     
         17 . The flow regulator of  claim 16 , wherein the concave surface of the body of the membrane faces the outlet of the housing, and wherein the membrane is biased when the membrane is in the second position. 
     
     
         18 . The flow regulator of  claim 16 , wherein the membrane is biased into the flow path in the second position. 
     
     
         19 . The flow regulator of  claim 16 , wherein the housing includes a membrane seat configured to engage a portion of the membrane when the membrane is in the second position. 
     
     
         20 . The flow regulator of  claim 19 , wherein the membrane seat defines a channel in fluid communication with the outlet of the housing, the channel at least partially restricting flow between the inlet and the outlet of the housing when the membrane is in the second position. 
     
     
         21 . The flow regulator of  claim 19 , wherein the housing comprises first and second portions, and wherein the membrane seat is provided on a second portion of the housing. 
     
     
         22 . The flow regulator of  claim 16 , wherein the inlet of the housing comprises one of a male luer fitting and a female luer fitting, and wherein the outlet of the housing comprises the other of the male luer fitting and the female luer fitting. 
     
     
         23 . The flow regulator of  claim 1 , further comprising a valve body positioned within the interior space and defining a passageway, wherein the membrane comprises a body and a plurality of flexible tabs extending radially outward from the body, the plurality of flexible tabs securing the membrane to the valve body. 
     
     
         24 . The flow regulator of  claim 23 , wherein the membrane is positioned within the passageway of the valve body. 
     
     
         25 . The flow regulator of  claim 23 , wherein the valve body has a first end secured to the housing and a second end configured to receive a tube. 
     
     
         26 . The flow regulator of  claim 23 , wherein the membrane and the valve body define a plurality of openings between the plurality of flexible tabs, the plurality of openings providing a flow passageway between the inlet and the outlet of the housing. 
     
     
         27 . The flow regulator of  claim 23 , wherein the housing includes a membrane seat configured to engage the membrane when the membrane is in the second position. 
     
     
         28 . The flow regulator of  claim 27 , wherein the membrane seat defines a channel that is in fluid communication with the outlet of the housing, the channel partially restricting flow between the inlet and the outlet of the housing when the membrane is in the second position. 
     
     
         29 . The flow regulator of  claim 1 , wherein the membrane comprises a body defining an opening therethrough, the body of the membrane having a convex surface and a concave surface, the convex surface of the membrane facing the outlet of the housing, the membrane configured to move between the first and second positions in response to a pressure differential acting on the convex surface and the concave surface of the membrane. 
     
     
         30 . The flow regulator of  claim 29 , further comprising a spherical shaped projection positioned between the membrane and the outlet of the housing, the projection engaging the housing and the membrane when the membrane is in the first and second positions. 
     
     
         31 . The flow regulator of  claim 29 , wherein the housing includes a membrane seat configured to engage the membrane when the membrane is in the second position, the membrane seat defining a channel that is in fluid communication with the outlet of the housing, the channel partially restricting flow between the inlet and the outlet of the housing when the membrane is in the second position.