Injection apparatus

Patent metadata

Field	Value
Publication number	US-9717856-B2
Application number	US-201414256379-A
Country	US
Kind code	B2
Filing date	Apr 18, 2014
Priority date	Dec 4, 2009
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

An injection apparatus includes a counter wheel that is incremented by the dose delivery mechanism each time the device is fired. The apparatus includes a final dose disabling mechanism that prevents further usage once the final dose has been delivered. An anti-tamper feature is provided to prevent inadvertent or premature initialisation of the apparatus.

First claim

The invention claimed is:

1. An injection apparatus, comprising: a drive unit actuatable to allow movement of a ratchet drive shaft to deliver a dose upon each such actuation, the ratchet drive shaft being mounted for rotary movement and rotates to deliver a dose; and
a counter member drivingly connected to said ratchet drive shaft,
wherein the counter member comprises a counter wheel having a toothed surface meshing with an idler cog, and said ratchet drive shaft carries one or more cog teeth for engaging the teeth of the idler cog such that the counter wheel is incremented by each dose delivery such that a cumulative dose count by incrementing the counter wheel by a single uniform amount indicative of a usage, irrespective of the dose magnitude.

2. The injection apparatus according to claim 1 , wherein said drive unit includes an elongate drive plunger threadedly engaged with said ratchet drive shaft and adapted to be advanced longitudinally to deliver a dose upon corresponding rotary movement of said ratchet drive shaft.

3. The injection apparatus according to claim 1 , wherein said ratchet drive shaft cog teeth engage the idler cog intermittently, once per dose delivery.

4. The injection device according to claim 1 , wherein said counter member is incremented part way through a dose delivery cycle.

5. The injection apparatus according to claim 2 , wherein said drive unit includes a dose setting element for being manually moved to energies an energy storage device associated with said ratchet drive shaft, and a releasable trigger for holding and releasing said ratchet drive shaft in and from an energized condition.

6. The injection apparatus according to claim 5 , including a blocking arrangement for blocking movement of said dose setting element after said drive plunger has advised to a final dose position, thereby to prevent further dose setting.

7. The injection apparatus according to claim 6 , wherein said drive unit includes a drive transfer element that rotates with, or is integral with, said dose setting element, the drive transfer element being connected to said ratchet drive shaft by a latching arrangement, wherein
the blocking arrangement comprises lugs provided on the drive transfer element and lugs provided on the plunger, such that the lugs move into engagement with each other when the drive plunger advances towards a final dose position, thereby substantially preventing further dose setting movement.

8. The injection device according to claim 5 , including an externally visible color change indicator for indicating when said drive is in the energized condition.

9. The injection apparatus according to claim 1 , adapted to deliver fixed volume doses.

10. The injection apparatus according to claim 1 , adapted to deliver doses of adjustable volume.

11. The injection apparatus according to claim 1 , wherein said drive unit includes a dose setting element for being manually moved to energize an energy storage device associated with said ratchet drive shaft, and a releasable trigger for holding and releasing said ratchet drive shaft in and from an energized condition.

Assignees

• Nicholls Clive
• Wozencroft Robert Michael
• Marshall Jeremy
• Owen Mumford Ltd

Inventors

• Nicholls Clive
• Wozencroft Robert Michael
• Marshall Jeremy

Classifications

• A61M2005/3125

  specific display means, e.g. to indicate dose setting · CPC title

• A61M2005/2073

  preventing premature release, e.g. by making use of a safety lock · CPC title

• A61M5/2033

  Spring-loaded one-shot injectors with or without automatic needle insertion (multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287) · CPC title

• A61M5/3157

  Means providing feedback signals when administration is completed (A61M5/20 takes precedence) · CPC title

• A61M2205/584

  having a color code · CPC title