Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
189 words
A hemodialysis apparatus comprising: a dialyzer having a membrane, a first chamber, and a second chamber separated from said first chamber by said membrane, said first chamber for coupling into a dialyzing liquid path, and said second chamber for coupling into a blood path; a dialyzing liquid source; a suction pump disposed in the dialyzing liquid path downstream from the dialyzer for controlling transmembrane pressure in the dialyzer; a restrictor means disposed in the dialyzing liquid path upstream of the dialyzer; a changeover valve having a first outlet, a second outlet, and an inlet coupled to receive dialyzing liquid downstream from said suction pump; a discharge port coupled to said first outlet; volume-measuring means for measuring volume of ultrafiltrate liquid; means for determining the transmembrane pressure in the dialyzer; control means, said control means being coupled at least to the transmembrane pressure determining means for controlling the suction pump in response to transmembrane pressure; and a return line coupled to said second outlet of said first changeover valve and connected to the dialyzing liquid source for returning the dialyzing liquid to the dialyzing liquid source in a closed circuit.
Claim 2
Dependent Claim
189 words
A hemodialysis apparatus comprising: a dialyzer having a membrane, a first chamber, and a second chamber separated from said first chamber by said membrane, said first chamber for coupling into a dialyzing liquid path, and said second chamber for coupling into a blood path; a dialyzing liquid source; a suction pump disposed in the dialyzing liquid path downstream from the dialyzer for controlling transmembrane pressure in the dialyzer; a restrictor means disposed in the dialyzing liquid path upstream of the dialyzer; a changeover valve having a first outlet, a second outlet, and an inlet coupled to receive dialyzing liquid downstream from said suction pump; a discharge port coupled to said first outlet; volume-measuring means for measuring volume of ultrafiltrate liquid; means for determining the transmembrane pressure in the dialyzer; control means, said control means being coupled at least to the transmembrane pressure determining means for controlling the suction pump in response to transmembrane pressure; and a return line coupled to said second outlet of said first changeover valve and connected to the dialyzing liquid source for returning the dialyzing liquid to the dialyzing liquid source in a closed circuit.
Claim 3
Dependent Claim
28 words
A hemodialysis apparatus according to claim 1 wherein the dialyzing liquid source includes a mixing chamber and wherein said volume measuring means is coupled to the mixing chamber.
Claim 4
Dependent Claim
34 words
A hemodialysis apparatus according to claim 2, wherein said volume-measuring means comprises a riser and further includes a first volume-sensing line coupled from said volume-measuring means to said control means for determining ultrafiltration rate.
Claim 5
Dependent Claim
82 words
A hemodialysis apparatus according to claim 2, further including a concentrate container, a concentrate pump and shut-off valve, the shut-off valve being coupled via a freshwater inlet line to a fresh water inlet which is blocked by said shut-off valve during measuring phases under control of said control means via a valve control line, the concentrate pump being coupled via a pump control line to said control means and which is turned off during measuring phases under control of said control means.
Claim 6
Dependent Claim
51 words
A hemodialysis apparatus according to claim 2 further including an overflow line from said mixing chamber and an overflow valve in said overflow line, said overflow valve being coupled to said control means via a valve control line and which is blocked under control of said control means during recirculation phases.
Claim 7
Dependent Claim
31 words
A hemodialysis apparatus according to claim 1, wherein said volume-measuring means further includes a quantity-counting flow meter coupled via a second volume-sensing line to said control means for determining ultrafiltration rate.
Claim 8
Dependent Claim
79 words
A hemodialysis apparatus according to claim 1, further including a set value input means coupled to said control means for providing preselected values to said control means, and wherein said control means is coupled via changeover valve control line to said changeover valve, via a transmembrane pressure control line to said transmembrane pressure determining means, and via a suction pump control line to said suction pump thereby to convert a single-pass-type hemodialysis apparatus into a feedback-controlled recirculating-type hemodialysis apparatus.