Dose counter for inhaler and method for counting doses

Patent metadata

Field	Value
Publication number	US-10086156-B2
Application number	US-201514699567-A
Country	US
Kind code	B2
Filing date	Apr 29, 2015
Priority date	May 18, 2010
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A dose counter for a metered dose inhaler includes an incremental counting system for counting doses. The incremental counting system has a main body, an actuator arranged to be driven in response to canister motion and to drive an incremental output member in response to canister motion. The actuator and incremental output member are configured to have predetermined canister fire and count configurations in a canister fire sequence. The canister fire configuration is determined by a position of the actuator relative to a datum at which the canister fires medicament and the count configuration is determined by a position of the actuator relative to the datum at which the incremental count system makes an incremental count. The actuator is arranged to reach a position in the count configuration at or after a position in the canister fire configuration.

First claim

What is claimed is:

1. A dose counter for a metered dose inhaler having a body arranged to retain a medicament canister of predetermined configuration for movement of the medicament canister relative thereto, the medicament canister containing an active drug; the dose counter comprising:
a ratchet wheel having a plurality of circumferentially spaced teeth,
an actuator comprising an actuator pawl arranged to engage with a first tooth of the ratchet wheel, wherein the actuator can be driven in response to canister motion to drive the ratchet wheel to rotate,
a count pawl arranged to engage with a second tooth of the ratchet wheel, wherein as the ratchet wheel is driven by the actuator to rotate, the count pawl rides along a forward surface of the second tooth and resiliently jumps over the second tooth, and
a dosage indicator associated with the count pawl,
wherein the actuator is arranged to define a first reset position in which the actuator pawl is brought into engagement with the first tooth,
wherein the actuator is further arranged such that, during a canister fire sequence, when the actuator is in a second position, which is after the first reset position and at a canister fire configuration, the medicament canister fires medicament before the dose counter reaches a count configuration, and when the actuator is in a third position after the second position, the count pawl resiliently jumps over the second tooth and the dose counter reaches the count configuration, whereby the dosage indicator has indicated a count,
wherein, in the canister fire configuration, the actuator pawl is below a datum plane which passes through a shoulder of a valve stem block configured to receive the medicament canister.

2. A dose counter as claimed in claim 1 in which the actuator is displaced less than 1 mm relative to the body between its locations in the canister fire and count configurations.

3. A dose counter as claimed in claim 1 wherein the dosage indicator includes a tape with incremental dose indicia located thereon, the tape being positioned on a tape stock bobbin and arranged to unwind therefrom.

4. The dose counter as claimed in claim 3 , wherein the incremental dose indicia on the tape is in the form of even numbers and the body includes a dose marker that points to a location either at one of the even numbers or between two adjacent even numbers.

5. A dose counter as claimed in claim 1 in which the actuator and ratchet wheel are arranged to provide a start configuration at which the actuator is spaced from the ratchet wheel, and an end configuration at which the actuator disengages from the ratchet wheel during the canister fire sequence.

6. A dose counter as claimed in claim 5 in which:
(a) the actuator is arranged to be located about 1.5 to 2.0 mm from its location in the fire configuration when in the start configuration;
(b) the actuator is arranged to be located about 1.0 to 1.2 mm from its location in the fire configuration when in the reset configuration; or
(c) the actuator is arranged to be located about 1.1 to 1.3 mm from its location in the fire configuration when in the end configuration.

7. A dose counter as claimed in claim 5 in which the body includes a formation for forcing the actuator to disengage from the ratchet wheel when the actuator is moved past the end configuration.

8. A dose counter as claimed in claim 5 in which:
(a) the actuator is arranged to be located about1.5 to 2.0 mm from its location in the fire configuration when in the start configuration;
(b) the actuator is arranged to be located about 1.0 to 1.2 mm from its location in the fire configuration when in the reset configuration; and
(c) the actuator is arranged to be located about 1.1 to 1.3 mm from its location in the fire configuration when in the end configuration.

9. A dose counter as claimed in claim 1 , wherein the count pawl and the ratchet wheel are arranged to permit one way incremental relative motion therebetween.

10. A dose counter as claimed in claim 9 in which the actuator and ratchet wheel are arranged to provide a start configuration at which the actuator is spaced from the ratchet wheel, and an end configuration at which the actuator disengages from the ratchet wheel during the canister fire sequence and in which the count pawl is substantially fixedly mounted on the body and in which the count pawl is arranged to be capable of repeatedly engaging the teeth of the ratchet wheel in anti-back drive interlock configurations as the dose counter is operated, the count pawl being positioned so that the ratchet wheel is halfway, or substantially halfway, moved from one anti-back interlock configuration to the next when the actuator and ratchet wheel are in the end configuration thereof.

11. An inhaler comprising the body arranged to retain the medicament canister of predetermined configuration and the dose counter as claimed in claim 1 .

12. An inhaler as claimed in claim 11 in which the body includes a canister-receiving portion and a separate counter chamber; the body, ratchet wheel and actuator being located inside the counter chamber, the body of the inhaler having wall surfaces separating the canister-receiving portion and the counter chamber, the wall surfaces being provided with a communication aperture, an actuation member extending through the communication aperture to transmit canister motion to the actuator.

13. The dose counter of claim 1 , wherein the shoulder is a bottom surface within the value stem block and the datum plane is perpendicular to a direction of the movement of the medicament canister.

Assignees

• Ivax Pharmaceuticals Ireland
• Norton Waterford Ltd
• Teva Pharma Ireland

Inventors

• Walsh Declan
• Fenlon Derek
• Kaar Simon
• Hazenberg Jan Geert
• Buck Daniel
• Clancy Paul
• Uschold Robert Charles
• Karg Jeffrey A

Classifications

• A61M2207/00

  Methods of manufacture, assembly or production · CPC title

• A61M2210/1025

  Respiratory system (A61M2210/0618 take precedence) · CPC title

• A61M11/00 Primary

  Sprayers or atomisers specially adapted for therapeutic purposes (in general B05B; {aerosol containers B65D83/14}) · CPC title

• A61M2207/10

  Device therefor · CPC title

• A61M15/0071

  having a display or indicator · CPC title