Injection device with dose interruption fail safe

Patent metadata

Field	Value
Publication number	US-2023398302-A1
Application number	US-202318239717-A
Country	US
Kind code	A1
Filing date	Aug 29, 2023
Priority date	Jul 17, 2018
Publication date	Dec 14, 2023
Grant date	—

Abstract

A dose setting mechanism is provided that includes a dose knob, a dose selector, a radial projecting rib and a snap element. The radial projecting rib is positioned circumferentially on an inside surface of the dose selector. The snap element includes a protrusion. The protruding rib has a reduced section that allows the protruding rib to move axially relative to the protrusion to initiate dose delivery.

First claim

1 . A dose setting mechanism comprising:
a dose knob; a dose selector; a radial projecting rib positioned circumferentially on an inside surface of the dose selector; and a snap element comprising a protrusion, wherein the protruding rib has a reduced section that allows the protruding rib to move axially relative to the protrusion to initiate dose delivery.

2 . The dose setting mechanism of claim 1 , wherein the reduced section comprises a ramped surface that engages the protrusion to allow the reduced section to move axially relative to the protrusion to initiate dose delivery.

3 . The dose setting mechanism of claim 1 , wherein:
the knob moves proximally to initiate an injection, and the knob cannot move into a distal position while the protrusion is located at the reduced section once the protrusion has passed the reduced section.

4 . The dose setting mechanism of claim 1 , wherein a non-chamfered side of the reduced section engages with a side of the protrusion once the protrusion has passed the reduced section to prevent the knob from moving in a distal direction.

5 . The dose setting mechanism of claim 1 , wherein the protrusion on the snap element flexes to overcome the reduced section when the knob is pressed proximally to initiate an injection.

6 . The dose setting mechanism of claim 1 , wherein the protruding rib has a cut-out at a zero position.

7 . The dose setting mechanism of claim 1 , wherein the protrusion has a lead-in chamfer.

8 . The dose setting mechanism of claim 1 , wherein the reduced section is aligned with a dose stop provided on the dose selector.

9 . The dose setting mechanism of claim 8 , wherein the dose knob can only move axially relative to the snap element when the protrusion or a further protrusion of the snap element is engaged with the dose stop of the dose selector.

10 . A dose setting mechanism comprising:
a dose knob; a dose selector, a radial projecting rib positioned circumferentially on an inside surface of the dose selector; and a snap element having a protrusion, wherein a release of the knob during an injection introduces friction between the protrusion and the rib.

11 . The dose setting mechanism of claim 10 , wherein the friction stops the injection.

12 . The dose setting mechanism of claim 10 , wherein the friction stops a rotation of the snap element.

13 . The dose setting mechanism of claim 10 , wherein the protruding rib has a friction surface.

14 . The dose setting mechanism of claim 13 , wherein the friction surface comprises a plurality of grooves.

15 . The dose setting mechanism of claim 14 , wherein the protrusion of the snap element comprises a clicker that engages the plurality of grooves when the axial proximal force is reduced.

16 . The dose setting mechanism of claim 10 , further comprising a rubber-like material on at least one of a friction surface of the protruding rib and the protrusion of the snap element.

17 . The dose setting mechanism of claim 10 , further comprising a torsion spring,
wherein the torsion spring at least assists a user in providing a dispense force for dispensing a medicament with the dose setting mechanism.

18 . The dose setting mechanism of claim 17 , wherein the torsion spring is strong enough to maintain an injection.

19 . The dose setting mechanism of claim 10 , wherein the dose selector is held at the radial projecting rib in a manner such that the knob cannot jump out in a distal direction when an axial force exerted on the dose knob is reduced once an injection has been started.

20 . The dose setting mechanism of claim 10 , wherein the protrusion engages with the radial projecting rib when an axial force exerted on the dose knob is reduced.

Assignees

• Medmix Switzerland Ag

Inventors

• Keitel Joachim
• Bechtold Herbert

Classifications

• A61M5/31538 Primary

  Permanent blocking, e.g. by medical personnel · CPC title

• A61M5/3146

  Priming, e.g. purging, reducing backlash or clearance · CPC title

• A61M5/31541

  Means preventing setting of a dose beyond the amount remaining in the cartridge · CPC title

• A61M5/31551

  including axial movement of dose setting member · CPC title

• A61M2005/3126

  Specific display means related to dosing · CPC title