RESERVOIR FLUID VOLUME ESTIMATOR AND MEDICAL DEVICE INCORPORATING SAME

• US 20140088556A1
• Filed: 11/26/2013
• Published: 03/27/2014
• Est. Priority Date: 08/21/2012
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Bazargan, Afshin, Makaveev, Bozhil, Wang, Yongbo, Wu, Ben, Vazquez, Pablo, Fonacier, EJMar, Weaver, Andrew E.
• Granted Patent: US 9,682,188 B2
• Time in Patent Office: Days
• US Class Current: 604/506
• CPC Class Codes: A61M 5/1684 by detecting the amount of infusate remaining, e.g. signalling end of infusion
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 40/63 for local operation

Abstract

Apparatus are provided for infusion devices and related control systems and methods. In one embodiment, an infusion device includes a voided portion adapted to receive a shaft portion that includes a shaft coupled to a plunger of a reservoir. The shaft portion includes a detectable feature having an optically detectable pattern such as gray code, and the infusion device includes a sensing arrangement having an optical sensor proximate the voided portion to sense the detectable feature. In some embodiments, a control module is coupled to the sensing arrangement to determine a remaining amount of fluid in the reservoir based at least in part on the sensed position of the detectable feature. In embodiments, the optical sensor detects the sensed position of the shaft based on the detectable feature only when the reservoir is replaced and/or after each delivery of fluid to reduce power consumption.

Claims

1. An infusion device, comprising:

a voided portion to receive a shaft portion including a shaft coupled to a plunger of a reservoir, the shaft further including a detectable feature, wherein the detectable feature is an optically detectable pattern; and

a sensing arrangement proximate the voided portion to sense the detectable feature, wherein the sensing arrangement includes an optical sensor.

2. The infusion device of claim 1, wherein the optically detectable pattern is a binary code.

3. The infusion device of claim 2, wherein the binary code is a gray code having a plurality of rows arranged along the shaft.

4. The infusion device of claim 3, wherein the gray code is a seven bit gray code.

5. The infusion device of claim 3, wherein each row of said plurality of rows of the gray code has a unique pattern indicative of a position of the shaft.

6. The infusion device of claim 3, wherein each row of said plurality of rows of the gray code has a unique pattern indicative of a quantity of fluid in the reservoir.

7. The infusion device of claim 3, wherein the optical sensor detects at least one of the plurality of rows of the gray code.

8. The infusion device of claim 3, wherein the optical sensor has a resting off mode and the optical sensor turns on after a movement of the shaft to detect at least one of the plurality of rows of the gray code.

9. The infusion device of claim 1, wherein the sensing arrangement further includes at least one light emitting element.

10. The infusion device of claim 1, further including a control module coupled to the sensing arrangement to obtain a position of the shaft using the sensing arrangement.

11. The infusion device of claim 1, further including a control module coupled to the sensing arrangement to turn on the optical sensor upon movement of the shaft.

12. The infusion device of claim 1, further including a control module to determine an amount of fluid in the reservoir based on at least a portion of the optically detectable pattern sensed by the optical sensor.

13. The infusion device of claim 1, further including a control module to determine an amount of fluid in the reservoir based on an image of at least a portion of the optically detectable pattern obtained by the optical sensor, wherein the optical sensor is a camera.

14. The infusion device of claim 13, the control module further providing a low fluid notification when the amount is less than a threshold value.

15. The infusion device of claim 12, the control module further obtaining a measured position of the shaft using the optically detectable pattern to determine the amount of fluid in the reservoir based on the measured position.

16. An infusion device comprising:

a reservoir having a plunger disposed within a barrel portion;

a shaft coupled to the plunger, the shaft including a detectable feature, the detectable feature including an optically detectable pattern; and

a sensing arrangement proximate the shaft to sense a position of the detectable feature, the sensing arrangement including an optical sensor to detect the optically detectable pattern.

17. The infusion device of claim 16, further comprising a control module coupled to the sensing arrangement to determine a remaining amount of fluid in the reservoir based at least in part on the detectable feature and provide a low fluid notification when the remaining amount is less than a threshold value.

18. A method estimating an amount of fluid in a reservoir of an infusion device, the reservoir including a plunger coupled to a shaft such that displacement of the shaft results in displacement of the plunger, the infusion device including a sensing arrangement having an optical sensor to sense a detectable feature on the shaft, the detectable feature including a binary code, the method comprising:

sensing at least a portion of the binary code by the optical sensor; and

determining a remaining amount of fluid in the reservoir based at least in part on at least a portion of the binary code sensed by the optical sensor.

19. The method of claim 18, further including:

turning on the optical sensor after a movement of the shaft to detect at least a portion of the binary code;

turning off the optical sensor between two or more movements of the shaft.

20. The method of claim 18, further including:

obtaining a measured shaft position based at least in part on a portion of the binary code sensed by the sensing arrangement;

determining a remaining amount of fluid in the reservoir based on the measured shaft position; and

providing a low fluid notification when the remaining amount is less than a threshold value.