Pumping system
AssigneeIsco, Inc.
InventorsFrederick A. Nabity, Paul G. Wright, Raymond Hulinsky, Douglas T. Carson
Life of this patent
Estimating the term…
Abstract
To draw samples from a source of liquid, a pumping system measures the amount of liquid being pumped by detecting pump cycles and calculating the pumped liquid from this measurement and stored data including conduit size, pressure head and statistical data to correlate detected pump cycles with volume of liquid pumped. Pressure pulses caused by a peristaltic pump are sensed by a piezoelectric film positioned on an inlet conduit connecting the pump to the source of water and, when the liquid reaches a predetermined point determined by the nature of the pulses, the pulses are counted to determine the number of pump cycles.
Claims18
A pumping system including:
- a pump;
- a sensor at a distance from the pump sufficiently close to detect the difference in amplitude of strain when liquid reaches a predetermined point from amplitude before it reaches the predetermined point;
- a flexible tube;
- said sensor including a fixture;
- a strain-sensitive film partly stretched in the fixture wherein said flexible tube is mounted in the fixture at least a portion of the strain-sensitive film being in contact with the flexible tube;
- and electrical connections to the strain-sensitive film adapted to conduct electrical pulses generated by periodic strains in the strain-sensitive film whereby pressure pulses sensed by pumping transmitted through the flexible tube may be detected.
A method of making a pumping system comprising the steps of:
- mounting a sensor at a distance from a pump sufficiently close to detect the difference in amplitude of strain when liquid reaches a predetermined point from amplitude before it reaches the predetermined point;
- wherein the sensor is made by mounting a flexible tube in a fixture;
- partly stretching a strain-sensitive film in the fixture wherein at least a portion of the strain-sensitive film is in contact with the flexible tube;
- and providing electrical connections to the strain-sensitive film adapted to sense periodic strains whereby the pulses transmitted through the flexible tube may be detected.
A pumping system including:
- a pump;
- a sensor at a distance from the pump sufficiently close to detect the difference in amplitude of strain when liquid reaches a predetermined point from amplitude of strain before it reaches the predetermined point;
- a flexible tube;
- said sensor including a fixture;
- a strain-sensitive film partly stretched in the fixture wherein said flexible tube is mounted in the fixture at least a portion of the strain-sensitive film being in contact with the flexible tube;
- and electrical connections to the strain-sensitive film adapted to conduct electrical pulses generated by periodic strains in the strain-sensitive film whereby pressure pulses sensed by pumping transmitted through the flexible tube may be detected;
- and
- a pump tubing life indicator.
A pumping system including:
- a pump;
- a sensor at a distance from the pump sufficiently close to detect the difference in amplitude of strain when liquid reaches a predetermined point from amplitude before it reaches the predetermined point;
- a flexible tube;
- said sensor including a fixture;
- a strain-sensitive film partly stretched in the fixture wherein said flexible tube is mounted in the fixture at least a portion of the strain-sensitive film being in contact with the flexible tube;
- and electrical connections to the strain-sensitive film adapted to conduct electrical pulses generated by periodic strains in the strain-sensitive film whereby pressure pulses sensed by pumping transmitted through the flexible tube may be detected;
- means electrically connected to said electrical connections for distinguishing between pulses caused by pressure changes after the liquid has reached the predetermined point from pulses caused by one of splashing and surging of liquid before the liquid has reached the predetermined point.
Dependencies are inferred from the claim text.