System and method for trapping air bubbles

Patent metadata

Field	Value
Publication number	US-9623196-B2
Application number	US-201113221742-A
Country	US
Kind code	B2
Filing date	Aug 30, 2011
Priority date	Aug 30, 2011
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

An air trap is disclosed that includes a body having a sealed interior space with an inner wall, a center axis, and an inlet and an outlet on the center axis. The air trap also includes at least one projection disposed within the interior space and coupled to the inner wall. The at least one projection extends from the inner wall toward the center axis with an inner edge nearest to the center axis.

First claim

What is claimed is:

1. An air trap comprising:
a body having a sealed interior space with an inner cylindrical wall, a center axis, and an inlet and an outlet on the center axis, wherein the inlet and outlet each have a diameter;
a clear passage through the interior space that extends along the center axis from the inlet to the outlet, the clear passage having a diameter that is greater than or equal to the smaller of the inlet and outlet diameters; and
at least one projection disposed within the interior space and coupled to the inner cylindrical wall, the at least one projection extending toward the central axis from the inner cylindrical wall to the clear passage and having a surface configured to substantially retain air bubbles on the surface, wherein the at least one projection comprises a spiral shelf having an inner edge, and wherein the inner edge is spaced away from the center axis along the entire length of the spiral shelf by a first gap, so that the inner edge defines a perimeter of the clear passage from the inlet to the outlet along the axis and wherein a portion of the inner cylindrical wall forms a hollow cylinder having, in cross-section, substantially straight parallel sides that extend in a direction along the central axis, for at least one complete rotation of the spiral shelf.

2. The air trap of claim 1 , wherein the spiral shelf includes at least two complete rotations around the center axis.

3. The air trap of claim 1 , wherein the at least one projection is configured to project inward at an angle to the center axis.

4. The air trap of claim 1 , wherein:
the diameters of the inlet and outlet are less than or equal to a first diameter;
the interior space has a midpoint along the center axis between the inlet and outlet;
the interior space has a second diameter at the midpoint; and
the second diameter is equal to or larger than the first diameter.

5. The air trap of claim 4 , wherein the second diameter is at least twice as long as the first diameter.

6. The air trap of claim 1 , wherein the at least one projection comprises a plurality of holes through the projection each of the holes disposed between the inner wall and the clear passage.

7. The air trap of claim 1 , wherein the outlet is disposed within the interior space such that, when the air trap is oriented with the outlet over the inlet, a portion of the interior space is above the outlet.

8. The air trap of claim 1 , further comprising:
an outer shell surrounding the inner cylindrical wall; and
a plurality of passages through the inner cylindrical wall.

9. An air trap comprising:
a body having a sealed interior space with a cylindrical inner wall, a center axis, and an inlet and an outlet on the center axis;
a clear passage through the interior space that extends on the center axis from the inlet to the outlet; and
a plurality of shelves, each disposed within the interior space and coupled to the cylindrical inner wall, each shelf extending toward the center axis from the cylindrical inner wall to the clear passage and having an inner edge nearest to the clear passage, wherein a portion of the cylindrical inner wall forms a hollow cylinder having, in cross-section, substantially straight parallel sides that extend in a direction along the center axis, at least from one of the plurality of shelves to an adjacent one of the plurality of shelves.

10. An intravenous (IV) set comprising:
an air trap comprising:
a body having a sealed interior space with an inner cylindrical wall, a center axis, and an inlet and an outlet on the center axis; and
at least one projection disposed within the interior space and coupled to the inner cylindrical wall, the at least one projection extending toward the central axis from the inner cylindrical wall to a clear passage that extends through the interior space along the center axis, the at least one projection having an inner edge nearest to the clear passage, wherein the at least one projection comprises a spiral shelf having the inner edge, and wherein the inner edge is spaced away from the center axis along the entire length of the spiral shelf by a first gap, so that the inner edge defines a perimeter of the clear passage from the inlet to the outlet along the axis, wherein a portion of the inner cylindrical wall forms a hollow cylinder having, in cross-section, substantially straight parallel sides that extend in a direction along the central axis, for at least one complete rotation of the spiral shelf; and
at least one fluid conduit coupled to one of the inlet and outlet of the air trap.

11. The IV set of claim 10 , wherein:
the at least one fluid conduit has a first inner diameter;
the interior space has a length and a midpoint along the center axis between the inlet and outlet;
the interior space has a second inner diameter at the midpoint;
the second inner diameter is at least twice as long as the first inner diameter.

12. The IV set of claim 11 , wherein the spiral shelf includes at least two complete rotations around the center axis.

Assignees

• Kirkpatrick Gregg Rodne
• Carefusion 303 Inc

Inventors

• Kirkpatrick Gregg Rodne

Classifications

• A61M5/365

  Air detectors (A61M5/1684 takes precedence; in extracorporeal blood circuits A61M1/3626) · CPC title

• A61M1/3627

  Degassing devices; Buffer reservoirs; Drip chambers; Blood filters · CPC title

• A61M2206/16

  Rotating swirling helical flow, e.g. by tangential inflows · CPC title

• A61M1/1658

  Degasification · CPC title

• B01D19/0057

  the centrifugal movement being caused by a vortex, e.g. using a cyclone, or by a tangential inlet · CPC title