Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
174 words
A dialysis and ultrafiltration control system for controlling ultrafiltration taking place across a semipermeable membrane device, which comprises a dialysis liquid tank for containing dialysis liquid and which is open to the atmosphere, a level sensor for detecting the level of dialysis liquid contained in the open dialysis liquid tank, dialysis liquid withdrawal means in communication with the open dialysis liquid tank for withdrawing determined volumes of dialysis liquid, means for effecting the circulation of the stream of dialysis liquid which means includes two positive-flow pumps, one disposed upstream and the other downstream of the dialyzer so that the ultrafiltration of liquid being treated is adjusted, and feedback means leading from said level sensor to said positive-flow pumps, wherein the means for controlling ultrafiltration constitutes controlling the operation of the two pumps in relation to each other in response to the level of dialysis liquid sensed in the tank in such manner as to maintain a substantially constant level of dialysis liquid in said tank at a determined rate of withdrawal of dialysis liquid.
Claim 2
Dependent Claim
174 words
A dialysis and ultrafiltration control system for controlling ultrafiltration taking place across a semipermeable membrane device, which comprises a dialysis liquid tank for containing dialysis liquid and which is open to the atmosphere, a level sensor for detecting the level of dialysis liquid contained in the open dialysis liquid tank, dialysis liquid withdrawal means in communication with the open dialysis liquid tank for withdrawing determined volumes of dialysis liquid, means for effecting the circulation of the stream of dialysis liquid which means includes two positive-flow pumps, one disposed upstream and the other downstream of the dialyzer so that the ultrafiltration of liquid being treated is adjusted, and feedback means leading from said level sensor to said positive-flow pumps, wherein the means for controlling ultrafiltration constitutes controlling the operation of the two pumps in relation to each other in response to the level of dialysis liquid sensed in the tank in such manner as to maintain a substantially constant level of dialysis liquid in said tank at a determined rate of withdrawal of dialysis liquid.
Claim 3
Dependent Claim
35 words
A dialysis and ultrafiltration control system as defined in claim 1, wherein one of the two positive-flow pumps is driven by a constant speed motor and the other is driven by a variable speed motor.
Claim 4
Dependent Claim
60 words
A dialysis and ultrafiltration control system as defined in claim 2, where the pump driven by the constant speed motor is disposed upstream of the dialyzer and the other pump is disposed downstream of the dialyzer, and means for increasing the speed of the variable speed motor when the level of dialysis liquid in the tank decreases and vice versa.
Claim 5
Dependent Claim
60 words
A dialysis and ultrafiltration control system as defined in claim 2, where the pump driven by the constant speed motor is disposed downstream of the dialyzer and the other pump is disposed upstream of the dialyzer, and means for decreasing the speed of the variable speed motor when the level of dialysis liquid in the tank increases and vice versa.
Claim 6
Dependent Claim
24 words
A dialysis and ultrafiltration control system as defined in claim 1, wherein each of the two pumps is driven by a variable speed motor.
Claim 7
Dependent Claim
39 words
A dialysis and ultrafiltration control system as defined in claim 5, including means for increasing the speed of the variable speed motor driving the downstream pump when the level of dialysis liquid in the tank decreases and vice versa.
Claim 8
Dependent Claim
39 words
A dialysis and ultrafiltration control system as defined in claim 5, including means for decreasing the speed of the variable speed motor driving the upstream pump when the level of dialysis liquid in the tank increases and vice versa.
Claim 9
Dependent Claim
27 words
A dialysis and ultrafiltration control system as defined in claim 1, including means for monitoring a substantially constant rate of flow of dialysis liquid in the dialyzer.