ARRANGEMENT AND METHOD FOR DETERMINING A STOPPER POSITION

• US 20150174330A1
• Filed: 07/10/2013
• Published: 06/25/2015
• Est. Priority Date: 07/11/2012
• Status: Active Grant

• Current Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Original Assignee: Sanofi-Aventis Deutschland GmbH (Sanofi )
• Inventors: Nagel, Thomas, Richter, Rene, Witt, Robert, Guenther, Richard, Vogel, Johannes
• Granted Patent: US 9,592,345 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/3375 Acoustical, e.g. ultrasonic, measuring means
• CPC Class Codes: A61M 2205/3389 Continuous level detection A61M2205/3393 takes precedence
• CPC Class Codes: A61M 5/1684 by detecting the amount of infusate remaining, e.g. signalling end of infusion
• CPC Class Codes: A61M 5/315 Pistons; Piston-rods; Guiding, blocking or restricting the movement of the rod or piston; Appliances on the rod for facilitating dosing ; Dosing mechanisms
• CPC Class Codes: A61M 5/31568 Means keeping track of the total dose administered, e.g. since the cartridge was inserted
• CPC Class Codes: G01F 11/029 provided with electric controlling means G01F11/022 and G01F11/024 take precedence
• CPC Class Codes: G01F 17/00 Methods or apparatus for determining the capacity of containers or cavities, or the volume of solid bodies measuring linear dimensions to determine volume G01B
• CPC Class Codes: G01F 22/00 Methods or apparatus for measuring volume of fluids or fluent solid material, not otherwise provided for
• CPC Class Codes: G01S 15/36 with phase comparison between the received signal and the contemporaneously transmitted signal
• CPC Class Codes: G01S 15/88 Sonar systems specially adapted for specific applications seismic or acoustic prospecting or detecting G01V1/00

Abstract

The invention relates to an arrangement for determining a position (x) of a stopper relative to a container in a drug delivery device, comprising an acoustic source configured to emit an acoustic signal and an acoustic sensor configured to detect an acoustic signal, a processing unit for controlling the acoustic source and processing the detected acoustic signal for determining characteristics of the acoustic signal correlated with the position (x) of the stopper. Furthermore, the invention relates to a method for determining a position (x) of a stopper relative to a container in a drug delivery device, the method comprising the steps of emitting an acoustic signal from an acoustic source, detecting an acoustic signal caused by the emitted acoustic signal by means of an acoustic sensor, and processing the detected acoustic signal for determining characteristics of the acoustic signal correlated with the position (x) of the stopper by means of a processing unit.

Claims

1-14. -14. (canceled)

15. Drug delivery device with a container defining a cavity for a drug and a stopper for proximally delimiting the cavity and displacing the drug from the cavity, the drug delivery device further comprising an arrangement for determining a position (x) of the stopper relative to the container, the arrangement comprising an acoustic source configured to emit an acoustic signal and an acoustic sensor configured to detect an acoustic signal, a processing unit for controlling the acoustic source and processing the detected acoustic signal for determining characteristics of the acoustic signal correlated with the position (x) of the stopper.

16. The arrangement according to claim 15, characterized in that the acoustic source is aligned to emit the acoustic signal through a proximal opening of the container towards the stopper, wherein the processing unit is configured to control the acoustic source so as to emit a coded acoustic wave (U) and to determine a delay or phase shift of the detected acoustic wave related to the position (x).

17. The arrangement according to claim 16, characterized in that the acoustic wave (U) is an ultrasonic wave (U).

18. The arrangement according to claim 16, characterized in that the acoustic source and the acoustic sensor are integrated in a sound converter operatively switchable to act as either the acoustic source or the acoustic sensor.

19. The arrangement according to claim 15, characterized in that the acoustic source is aligned to emit the acoustic signal into a resonance volume, which is defined in one spatial dimension by the position of the stopper, wherein the processing unit is configured to vary the frequency (f) of the emitted acoustic signal within a pre-determined frequency range, wherein the processing unit is configured to detect a harmonic (f₁(x), f₂(x), f₃(x), f₄(x)) of a resonance frequency f_k characteristic for the resonance volume related to the position (x).

20. The arrangement according to claim 19, characterized in that the resonance volume is at least partially defined within a proximal end of the container.

21. The arrangement according to claim 19, characterized in that a tube section with essentially the same internal diameter as the container is arranged proximally adjacent the container for at least partially defining the resonance volume.

22. The arrangement according to claim 19, characterized in that the pre-determined frequency range is selected so as to match at least part of a range of linear frequency response of the acoustic source.

23. A method for determining a position (x) of a stopper relative to a container in a drug delivery device, the method comprising the steps of:

emitting an acoustic signal from an acoustic source,

detecting an acoustic signal caused by the emitted acoustic signal by means of an acoustic sensor,

processing the detected acoustic signal for determining characteristics of the acoustic signal correlated with the position (x) of the stopper by means of a processing unit.

24. The method according to claim 23, characterized in that the acoustic source is aligned to emit the acoustic signal through a proximal opening of the container towards the stopper, wherein the acoustic source is controlled so as to emit a coded acoustic wave (U) and wherein a delay or phase shift of the detected acoustic wave related to the position (x) is determined.

25. The method according to claim 24, characterized in that the acoustic wave (U) is an ultrasonic wave (U).

26. The method according to claim 24, characterized in that the acoustic source and the acoustic sensor are integrated in a sound converter which is operatively switched to act as either the acoustic source or the acoustic sensor.

27. The method according to claim 23, characterized in that the acoustic source is aligned to emit the acoustic signal into a resonance volume, which is defined in one spatial dimension by the position of the stopper, wherein the frequency (f) of the emitted acoustic signal is varied within a pre-determined frequency range, wherein a harmonic (f₁(x), f₂(x), f₃(x), f₄(x)) of a resonance frequency f_k characteristic for the resonance volume related to the position (x) is detected.

28. The method according to claim 27, characterized in that the pre-determined frequency range is selected so as to match at least part of a range of linear frequency response of the acoustic source.