Flow condition sensor assembly for patient infusion device

• US 7,887,505 B2
• Filed: 10/08/2003
• Issued: 02/15/2011
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Insulet Corporation
• Original Assignee: Insulet Corporation
• Inventors: Flaherty, J. Christopher
• Primary Examiner(s): KENNEDY, SHARON E
• Application Number:
  US10/681,688
• Publication Number:
  US 20040127844A1
• Time in Patent Office: 2,687 Days
• Field of Search: 604/67, 604/118, 604/131, 604/247, 604151-153, 604/30, 604/31, 604/167.01, 604/167.03, 417/256, 417/12, 417/38, 417/37, 417/44.9
• US Class Current: 604/67
• CPC Class Codes: A61M 2205/3327 Measuring
• CPC Class Codes: A61M 2205/3355 Controlling downstream pump pressure
• CPC Class Codes: A61M 2205/3576 with non implanted data transmission devices, e.g. using external transmitter or receiver
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: A61M 5/16804 Flow controllers
• CPC Class Codes: A61M 5/16809 by repeated filling and emptying of an intermediate volume pressure infusion using positive displacement pumps A61M5/142
• CPC Class Codes: A61M 5/16831 Monitoring, detecting, signalling or eliminating infusion flow anomalies low-level float-valves causing cut-off A61M5/40; indicating or recording presence, absence or direction of flow in general G01P13/0066
• CPC Class Codes: A61M 5/16854 by monitoring line pressure

Abstract

A device for delivering fluid to a patient including an exit port assembly adapted to connect to a transcutaneous patient access tool, a flow path extending from the exit port assembly, and a flow condition sensor assembly including a resilient diaphragm having opposing first and second surfaces. The first surface of the diaphragm is positioned against the flow path, and a chamber wall is positioned adjacent the second surface of the diaphragm and defines a sensor chamber against the second surface of the diaphragm. At least one sensor is arranged to provide a threshold signal when the second surface of the diaphragm expands into the chamber in response to at least one predetermined fluid flow condition occurring in the flow path.

Claims

1. A device for delivering fluid to a patient, comprising:

A) an exit port assembly adapted to connect to a transcutaneous patient access tool;

B) a flow path extending from the exit port assembly; and

C) a flow condition sensor assembly including,

a resilient diaphragm having opposing first and second surfaces, with the first surface positioned against the flow path,

a chamber wall positioned adjacent the second surface of the diaphragm and defining a sensor chamber adjacent the second surface of the diaphragm, and

at least one sensor arranged to provide a threshold signal when the second surface of the diaphragm expands into the chamber in response to at least one predetermined fluid flow condition occurring in the flow path.

2. A device for delivering fluid to a patient, comprising:

A) a flow path extending from the exit port assembly;

B) a flow condition sensor assembly including,

a resilient diaphragm having opposing first and second surfaces, with the first surface positioned against the flow path,

a chamber wall positioned adjacent the second surface of the diaphragm and defining a sensor chamber adjacent the second surface of the diaphragm, and

at least one sensor arranged to provide a threshold signal when the second surface of the diaphragm expands into the chamber by a predetermined amount; and

C) a processor connected to the sensor and programmed to provide a signal indicative of an undesired flow condition upon receiving the threshold signal from the sensor for more than a predetermined maximum period or for less than a predetermined minimum period.

3. A method for determining a fluid flow condition in a flow path, comprising:

positioning a first side of a resilient diaphragm against the flow path;

positioning a chamber wall adjacent a second surface of the diaphragm, the chamber wall defining a sensor chamber adjacent the second surface of the diaphragm;

providing a threshold signal when the second surface of the diaphragm expands into the chamber by a predetermined amount;

timing the duration of the threshold signal; and

providing a signal indicative of a predetermined flow condition if the duration of the threshold signal is greater than a predetermined maximum period or less than a predetermined minimum period.

4. A method according to claim 3, further comprising activating an alarm upon providing a signal indicative of a predetermined flow condition.

5. A method according to claim 3, further comprising providing the sensor chamber with a predetermined volume.

6. A method according to claim 3, further comprising providing the sensor chamber with a predetermined volume and providing a threshold signal when the second surface of the diaphragm contacts the chamber wall.

7. A method according to claim 3, further comprising providing the flow path with a substantially fixed and predetermined volume.

8. A method according to claim 3, wherein the predetermined fluid flow condition comprises one of an occlusion in the flow path, and an inadequate flow of fluid in the flow path.

9. A method according to claim 3, further comprising:

closing the flow path;

causing a volume of fluid at least equal to a volume of the sensor chamber to flow into the fluid path; and

providing a signal indicative of an occlusion test failure if the duration of the threshold signal is less than the predetermined maximum period.

10. A method according to claim 9, further comprising positioning a second diaphragm against the flow path.

11. A method according to claim 3, further comprising:

providing pulsitile flow of fluid within the flow path; and

monitoring the threshold signals between pulses of fluid.