Fluid line condition detection
First Claim
1. A fluid line condition detection apparatus coupled between a fluid supply and a fluid receiver, the apparatus comprising:
- a fluid line having an upstream segment coupled to the fluid supply for receiving fluid from the fluid supply at head pressure and a downstream segment coupled to the fluid receiver;
a fluid chamber disposed in fluid communication with the upstream segment and with the downstream segment of the fluid line;
control means for alternately opening the fluid chamber to fluid communication with the upstream segment of the fluid line and with the downstream segment of the fluid line, wherein when opened to the upstream segment, the chamber receives and stores fluid at head pressure and wherein when opened to the downstream segment, the chamber communicates the fluid stored at head pressure to fluid residing in the downstream segment thereby causing a pressure equalization pulse in the downstream segment;
pressure sensor means for sensing equilibrium pressure in the downstream segment and for providing an equilibrium signal representative thereof and for also sensing the pressure equalization pulse and for providing an equalization signal representative of the pressure equalization pulse; and
processor means responsive to said equilibrium signal and to said equalization signal for taking the difference between the equilibrium signal and the equalization signal and for integrating the difference in determining the head pressure.
12 Assignments
0 Petitions
Accused Products
Abstract
A compliant chamber is formed in a fluid line which connects a fluid supply to a fluid receiver. The compliant chamber is alternately in fluid communication with the upstream and downstream segments of the fluid line. When the chamber communicates with the upstream segment it receives and stores fluid at the head pressure. When the segment communicates with the downstream segment, a pressure equalization pulse occurs. A pressure sensor in the downstream segment measures the pressure equalization pulse which is proportional to the head pressure. Processing the equalization pulse with the downstream fluid system resistance, the compliance of the compliant chamber and the equilibrium pressure results in a determination of the head pressure. Comparing the head pressure to thresholds permits determination of an occlusion or empty fluid supply. Where a peristaltic pump is used, the chamber is formed between the end fingers of the pump.
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Citations
35 Claims
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1. A fluid line condition detection apparatus coupled between a fluid supply and a fluid receiver, the apparatus comprising:
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a fluid line having an upstream segment coupled to the fluid supply for receiving fluid from the fluid supply at head pressure and a downstream segment coupled to the fluid receiver; a fluid chamber disposed in fluid communication with the upstream segment and with the downstream segment of the fluid line; control means for alternately opening the fluid chamber to fluid communication with the upstream segment of the fluid line and with the downstream segment of the fluid line, wherein when opened to the upstream segment, the chamber receives and stores fluid at head pressure and wherein when opened to the downstream segment, the chamber communicates the fluid stored at head pressure to fluid residing in the downstream segment thereby causing a pressure equalization pulse in the downstream segment; pressure sensor means for sensing equilibrium pressure in the downstream segment and for providing an equilibrium signal representative thereof and for also sensing the pressure equalization pulse and for providing an equalization signal representative of the pressure equalization pulse; and processor means responsive to said equilibrium signal and to said equalization signal for taking the difference between the equilibrium signal and the equalization signal and for integrating the difference in determining the head pressure. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. A fluid line condition detection apparatus coupled between a fluid supply and the vascular system of a patient, the apparatus comprising:
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a fluid line having an upstream segment coupled to the fluid supply for receiving fluid from the fluid supply at head pressure and a downstream segment coupled to the vascular system of the patient; a fluid chamber comprising a flexible segment of the fluid line disposed between and in fluid communication with the upstream segment and with the downstream segment of the fluid line; control means for operating on the flexible segment of the fluid chamber to control the pressure of the fluid in the fluid line and for alternately opening the fluid chamber to fluid communication with the upstream segment of the fluid line and with the downstream segment of the fluid line, wherein when opened to the upstream segment, the chamber receives and stores fluid at head pressure and wherein when opened to the downstream segment, the chamber communicates the fluid stored at head pressure to fluid residing in the downstream segment thereby causing a pressure equalization pulse in the downstream segment; pressure sensor means for sensing the pressure equalization pulse and for providing an equalization signal representative of the pressure equalization pulse and for sensing equilibrium pressure in the downstream segment and for providing an equilibrium signal representative thereof; resistance means for providing a resistance signal representative of the resistance to fluid flow downstream of the fluid chamber; processor means for taking the difference between the equilibrium signal and the equalization signal, integrating said difference and scaling the integrated difference by the resistance signal in determining the head pressure, said processor means also for providing a head pressure signal representative of the determined head pressure; and an alarm generator which receives the head pressure signal, compares the received signal to a first threshold and if the head pressure signal is less than the first threshold, provides an occlusion alarm signal. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
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25. A method for detecting the condition of a fluid delivery system which includes a fluid line having an upstream segment coupled to a fluid supply and a downstream segment coupled to a fluid receiver, the delivery system having a fluid pressure control means for operating on a flexible segment of the fluid line to control the pressure of the fluid in the fluid line, the fluid upstream of the fluid pressure control means being at head pressure, the method comprising the steps of:
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storing fluid at the head pressure in a fluid chamber disposed in fluid communication with the upstream segment and with the downstream segment of the fluid line; alternately opening the fluid chamber to fluid communication with the upstream segment of the fluid line and with the downstream segment of the fluid line, wherein when opened to the upstream segment, the chamber receives and stores fluid at head pressure and wherein when opened to the downstream segment, the chamber communicates the fluid stored at head pressure to fluid residing in the downstream segment thereby causing a pressure equalization pulse in the downstream segment; sensing the equilibrium pressure in the downstream segment and providing an equilibrium signal representative thereof and also sensing the pressure equalization pulse and providing an equalization signal representative of the pressure equalization pulse; and processing the equalization signal to determine the head pressure including the steps of taking the difference between the equilibrium signal and the equalization signal and integrating the difference in determining the head pressure. - View Dependent Claims (26, 27, 28, 29, 30, 31, 32, 33, 34, 35)
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Specification