Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
285 words
A needle assembly for collecting one or more liquid samples from a source for subsequent discharge into evacuated containers, comprising (a) a housing having a forward end and a rearward end; (b) a sample collection chamber in said housing; (c) a first access opening in said forward end in liquid flow communication with said chamber; (d) a first cannula extending outwardly from said first access opening for insertion into said source; (e) a second access opening in said rearward end in flow communication with said chamber; (f) a second cannula positioned in said second access opening and in flow communication with said chamber; (g) valve means on said cannula for controlling discharge of liquid samples from said chamber into evacuated containers attached to said second cannula; the improvement characterized by (h) cooperating means on said forward end and said rearward end of said housing providing a fluid bleed passage means therebetween, said fluid bleed passage being separate from said flow communication between said chamber and said second access opening; (i) vent means in said housing providing flow communication with said fluid bleed passage and ambient; (j) swelling means in said fluid bleed passage responsive to aqueous containing materials passing therethrough for swelling and mechanically closing said fluid bleed passage upon contact with an aqueous containing material passing therethrough; (k) said swelling means only partially occupying said fluid bleed passage prior to contact with an aqueous containing material; (1) whereby when said first cannula engages said source, aqueous containing liquid enters said chamber, forcing any gas therein through said fluid bleed passage and said vent means, causing said liquid to come into contact with said swelling means which swells and mechanically closes said fluid bleed passage.
Claim 2
Dependent Claim
285 words
A needle assembly for collecting one or more liquid samples from a source for subsequent discharge into evacuated containers, comprising (a) a housing having a forward end and a rearward end; (b) a sample collection chamber in said housing; (c) a first access opening in said forward end in liquid flow communication with said chamber; (d) a first cannula extending outwardly from said first access opening for insertion into said source; (e) a second access opening in said rearward end in flow communication with said chamber; (f) a second cannula positioned in said second access opening and in flow communication with said chamber; (g) valve means on said cannula for controlling discharge of liquid samples from said chamber into evacuated containers attached to said second cannula; the improvement characterized by (h) cooperating means on said forward end and said rearward end of said housing providing a fluid bleed passage means therebetween, said fluid bleed passage being separate from said flow communication between said chamber and said second access opening; (i) vent means in said housing providing flow communication with said fluid bleed passage and ambient; (j) swelling means in said fluid bleed passage responsive to aqueous containing materials passing therethrough for swelling and mechanically closing said fluid bleed passage upon contact with an aqueous containing material passing therethrough; (k) said swelling means only partially occupying said fluid bleed passage prior to contact with an aqueous containing material; (1) whereby when said first cannula engages said source, aqueous containing liquid enters said chamber, forcing any gas therein through said fluid bleed passage and said vent means, causing said liquid to come into contact with said swelling means which swells and mechanically closes said fluid bleed passage.
Claim 3
Dependent Claim
64 words
The apparatus of claim 1, further characterized by said cooperating means comprising (a) an integral cylindrical extension on said rear end of said housing; (b) an integral annular extension on said front end of said housing; (c) the internal surface of said front end extension cooperating with the external surface of said rear end extension to form an annular fluid bleed passage means therebetween.
Claim 4
Dependent Claim
26 words
The apparatus of claim 1, further characterized by (a) aid swelling means is a hydrolyzed starch-polyacrylonitrile graft copolymer with side chains containing carboxamide and carboxylate groups.
Claim 5
Dependent Claim
65 words
The apparatus of claim 1, further characterized by said swelling means comprising a laminate, said laminate characterized by (a) a central layer of starch-polyacrylonitrile graft copolymer with side chains containing carboxamide and carboxylate groups; (b) an outer layer on each side of said central layer; (c) said outer layers comprised of non-woven fluid permeable sheets; and (d) said laminate positioned in said bleed passage means.
Claim 6
Dependent Claim
40 words
The apparatus of claim 2, further characterized by said swelling means comprising (a) an annular compressed tablet of hydrolyzed starch-polyacrylonitrile graft copolymer with side chains containing carboxamide and carboxylate groups; and (b) said tablet positioned in said bleed passage means.
Claim 7
Dependent Claim
27 words
The apparatus of claim 5, further characterized by (a) said annular tablet is comprised of powder compressed to a density of about 2.2 grams per cubic centimeter.
Claim 8
Dependent Claim
40 words
The apparatus of claim 5, further characterized by (a) the clearance fit between said compressed tablet and the walls of said bleed passage containing said tablet is within the range of between about 0.003 inches interference and 0.008 inches clearance.
Claim 9
Dependent Claim
26 words
The apparatus of claim 7, further characterized by (a) said clearance fit is within the range of between about 0.001 inches clearance and 0.005 inches clearance.
Claim 10
Dependent Claim
67 words
The apparatus of claim 2, further characterized by said swelling means comprising (a) a laminate formed of three layers into an annular form; (b) said laminate consisting of (1) a central layer of a starch-polyacrylonitrile graft copolymer with side chains containing carboxamide and carboxylate groups; (2) a outer layer on each side of said central layer; (3) each said outer layer comprised of non-woven fluid permeable sheets.
Claim 11
Dependent Claim
27 words
The apparatus of claim 9, further characterized by (a) the longitudinal extent of said annular laminate is within the range of between 0.08 inches and 0.10 inches.
Claim 12
Dependent Claim
21 words
The apparatus of claim 1, further characterized by (a) said housing including means for connecting a holder for an evacuated container.
Claim 13
Dependent Claim
19 words
The apparatus of claim 11, further characterized by (a) a holder for an evacuated container connected to said housing.
Claim 14
Dependent Claim
20 words
The apparatus of claim 1, further characterized by (a) said housing including means for viewing the contents of said chamber.
Claim 15
Dependent Claim
21 words
The apparatus of claim 13, further characterized by (a) said viewing means is transparent or translucent housing walls adjacent said chamber.