INJECTION DEVICES

• US 20130338601A1
• Filed: 03/02/2012
• Published: 12/19/2013
• Est. Priority Date: 03/02/2011
• Status: Active Grant

• Current Assignee: Owen Mumford
• Original Assignee: Owen Mumford
• Inventors: Cowe, Toby
• Granted Patent: US 9,744,306 B2
• Time in Patent Office: Days
• US Class Current: 604/189
• CPC Class Codes: A61M 2005/202 cocking means, e.g. to bias the main drive spring of an injector
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/208 Release is possible only when device is pushed against the skin, e.g. using a trigger which is blocked or inactive when the device is not pushed against the skin
• CPC Class Codes: A61M 2205/581 by audible feedback
• CPC Class Codes: A61M 2205/582 by tactile feedback
• CPC Class Codes: A61M 2205/583 by visual feedback
• CPC Class Codes: A61M 5/2033 Spring-loaded one-shot injectors with or without automatic needle insertion multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287
• CPC Class Codes: A61M 5/31535 Means improving security or handling thereof, e.g. blocking means, means preventing insufficient dosing, means allowing correction of overset dose
• CPC Class Codes: A61M 5/3157 Means providing feedback signals when administration is completed A61M5/20 takes precedence

Abstract

An injection device includes an injection complete indicator which includes its own bias and which is latched into a retracted position as the injection device is cocked. Upon firing the injection device, the injection complete indicator is kept in its retracted position until towards the end of the forward stroke of the drive mechanism, whereupon the injection complete indicator is unlatched and shoots forwardly under the influence of the bias to impact an abutment to generate an audible/tactile indication along with a visual indication.

Claims

1. An injection device including an injection complete indicator for providing a kinetic impact indication, the device including:

a housing (26);

a plunger (45) movable in said housing between cocked and fired positions under the influence of a plunger drive source (54);

an indicator element (20) movable between an extended position and a retracted position and being biased towards said extended position by an indicator bias (50);

an indicator latch arrangement (70,34) for latching said indicator element (20) in a retracted position;

a motion transfer arrangement (74) between the plunger and the indicator element for retracting said indicator element (20) to said retracted position as said plunger (45) is moved to its cocked position but allowing forward movement of said plunger relative to the indicator element;

the device being arranged such that, after firing, as the plunger (45) nears or reaches the end of its operating stroke, it enables release of the indicator latch arrangement (70,34) to cause the indicator element (20) to move to its extended position under the influence of said bias to impact a stop surface to create said kinetic impact.

2. An injection device according to claim 1, wherein said motion transfer arrangement comprises an abutment surface associated with one of said plunger (45) and said indicator element (20) and a cooperating projection (74) associated with the other thereof.

3. An injection device according to claim 1, wherein said indicator latch arrangement includes a flexible latch finger (34) associated with said housing and having a latching tooth (38) past which a flexible finger (70) on the indicator element (20) may snap past as the indicator element is moved to its retracted position.

4. An injection device according to claim 3, wherein the latch finger (34) associated with the housing is resiliently deflectable to allow said indicator finger (70) to move forwardly, with the deflection being prevented except when the plunger is at or near the end of its stroke.

5. An injection device according to claim 4, wherein the plunger (45) is movable longitudinally between its cocked and fired positions, and the body finger (34) extends generally longitudinally, with the plunger (45) having a support surface (62) which underlies the body finger (34), until the plunger nears or reaches the end of its stroke.

6. An injection device according to claim 3, wherein the latch tooth (38) comprises respective ramp surfaces facing in the cocking and firing directions respectively, with the ramp surfaces providing a profile in which the inclination of the ramp face first contacted by the indicator finger when moving to its retracted position is shallower than the other face, whereby the indicator finger can snap past the latch tooth when moving in the direction of retraction, but not in the opposite direction.

7. An injection device according to claim 1, wherein said indicator element also provides a visual indication on approaching or arriving at said extended position.

8. An injection device according to claim 1, wherein the indicator element (20) comprises an element of sleeve or part sleeve ??? mounted for sliding movement with respect to said housing.

9. An injection device according to claim 8, wherein said indicator element is provided with a forward facing edge adapted to impact a rearward facing surface associated with said housing (20).

11. An injection device according to claim 2, wherein said indicator latch arrangement includes a flexible latch finger (34) associated with said housing and having a latching tooth (38) past which a flexible finger (70) on the indicator element (20) may snap past as the indicator element is moved to its retracted position.

12. An injection device according to claim 4, wherein the latch tooth (38) comprises respective ramp surfaces facing in the cocking and firing directions respectively, with the ramp surfaces providing a profile in which the inclination of the ramp face first contacted by the indicator finger when moving to its retracted position is shallower than the other face, whereby the indicator finger can snap past the latch tooth when moving in the direction of retraction, but not in the opposite direction.

13. An injection device according to claim 5, wherein the latch tooth (38) comprises respective ramp surfaces facing in the cocking and firing directions respectively, with the ramp surfaces providing a profile in which the inclination of the ramp face first contacted by the indicator finger when moving to its retracted position is shallower than the other face, whereby the indicator finger can snap past the latch tooth when moving in the direction of retraction, but not in the opposite direction.

14. An injection device according to claim 2, wherein said indicator element also provides a visual indication on approaching or arriving at said extended position.

15. An injection device according to claim 3, wherein said indicator element also provides a visual indication on approaching or arriving at said extended position.

16. An injection device according to claim 4, wherein said indicator element also provides a visual indication on approaching or arriving at said extended position.

17. An injection device according to claim 5, wherein said indicator element also provides a visual indication on approaching or arriving at said extended position.

18. An injection device according to claim 6, wherein said indicator element also provides a visual indication on approaching or arriving at said extended position.

19. An injection device according to claim 2, wherein the indicator element (20) comprises an element of sleeve or part sleeve ??? mounted for sliding movement with respect to said housing.

20. An injection device according to claim 3, wherein the indicator element (20) comprises an element of sleeve or part sleeve ??? mounted for sliding movement with respect to said housing.

10. An injection device including an injection complete indicator, the device including:

a housing (26);

a plunger (45) movable in said housing between cocked and fired positions under the influence of a plunger drive source (54);

an indicator element (20) movable between a pre-firing position and an injection complete position;

the device being arranged such that, after firing, as the plunger (45) nears or reaches the end of its operating stroke, the indicator element (20) is caused to move to its injection complete position and wherein subsequent re-cocking of the plunger returns said indicator element (20) to its pre-firing position.