Optical bubble detection system
AssigneeZeuex, Inc.
InventorsJames A. Malmstrom, Kent F. Beck, Scott D. Miles
Life of this patent
Estimating the term…
Abstract
An optical sensor includes a sample cell through which a fluid flows, an optical sensor formed by an optical emitter and an optical detector. The sample cell and the optical sensor use light refraction to determine the presence and size of a bubble passing through the sample cell. A housing may also be included to provide better control over light refraction and to protect the optical sensor.
Claims51
A sample cell for monitoring the flow of a liquid, the sample cell comprising, a cell wall defining a conduit, the conduit having a triangular cross-section.
A sample cell for use in monitoring of air bubbles in an infusion set, the sample cell comprising first and second sidewalls disposed tangentially to one another at an angle of between about 45 to 100 degrees.
A method for monitoring air bubbles in an infusion set, the method comprising;
- selecting a sample cell having a first sidewall and a second sidewall, the first and second sidewall being disposed at an angle relative to one another between about 45 and 100 degrees and having a conduit formed therein;
- transmitting light from an optical signal emitter toward an optical signal detector and into the sample cell and refracting a greater amount of light toward the optical signal detector if air is present in the conduit.
A method for detecting bubbles in a sample cell, the method comprising;
- positioning a sample cell having a conduit therein between an optical signal emitter and an optical signal detector;
- and
- causing light to be refracted towards the optical signal detector if the conduit is filled with air, and not refracting light to the optical signal detector if the conduit is filled with liquid.
A method for forming a sample cell from flexible tubing the method comprising:
- selecting a sample cell container having a channel formed therein defining a pair of sidewalls sloping toward one another and being disposed at an angle offset from each other of between about 45 and 100 degrees;
- and
- engaging the flexible tube with the pair of sidewalls to deform the flexible tube so that the flexible tube has sidewalls disposed generally parallel to the pair of sidewalls of the sample cell container.
A sample cell container for forming a sample cell from a piece of flexible tubing, the sample cell container comprising;
- a lower portion having a channel formed therein, the channel having a pair of inwardly sloping sidewalls disposed tangentially to one another at an angle of between about 45 and 100 degrees.
A method for determining the presence of air in a sample cell, the method comprising;
- selecting a sample cell having a sidewall;
- directing light from an optical emitter along a plane toward the sample cell such that the sidewall of the sample cell is at an angle of less than normal from the plane;
- and
- selectively refracting the light through the sample cell so that the light is directed to an optical detector when the sample cell is substantially filled with air.
A method for monitoring for bubbles, the method comprising;
- selecting a sample cell having a first sidewall and a second sidewall on opposite sides of a conduit;
- and
- refracting light through the first sidewall, the conduit and the second sidewall such that the light reaches an optical signal detector when the sample cell has an air bubble disposed therein, and so that substantially none of the light passing through the conduit reaches the optical detector when the sample cell is filled with liquid.
Dependencies are inferred from the claim text.