Auto-injector with active agent container latching

• US 20050203466A1
• Filed: 12/17/2004
• Published: 09/15/2005
• Est. Priority Date: 12/18/2003
• Status: Active Grant

• Current Assignee: Ypsomed AG (Ypsomed Holding AG)
• Original Assignee: TecPharma Licensing AG (Ypsomed Holding AG)
• Inventors: Hommann, Edgar, Scherer, Benjamin
• Granted Patent: US 7,357,790 B2
• Time in Patent Office: Days
• US Class Current: 604/240
• CPC Class Codes: A61M 2005/2013 triggering of discharging means by contact of injector with patient body
• CPC Class Codes: A61M 2005/206 With automatic needle insertion
• CPC Class Codes: A61M 2005/2073 preventing premature release, e.g. by making use of a safety lock
• CPC Class Codes: A61M 2005/3118 via the distal end of a syringe, i.e. syringe end for mounting a needle cannula
• CPC Class Codes: A61M 2005/3247 Means to impede repositioning of protection sleeve from needle covering to needle uncovering position
• CPC Class Codes: A61M 2005/3267 Biased sleeves where the needle is uncovered by insertion of the needle into a patient's body
• CPC Class Codes: A61M 2205/273 preventing reuse, e.g. of disposables
• 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 5/31571 Means preventing accidental administration for automatic syringes A61M5/20
• CPC Class Codes: A61M 5/3158 performed by axially moving actuator operated by user, e.g. an injection button
• CPC Class Codes: A61M 5/3202 Devices for protection of the needle before use, e.g. caps A61M5/50 takes precedence; for infusion spikes A61M5/1626; protectors for sharps A61B50/3001
• CPC Class Codes: A61M 5/326 Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user

Abstract

In an elongated casing, an active agent container connected to an injection needle can be shifted axially by a spring force. Auto-injectors which are sold or distributed filled and with the springs tensed have to be provided with a needle protecting cap to ensure the sterility of the injection needle. When such a needle protecting cap is removed as preparation for using the auto-injector, a tensile force can be exerted on the active agent container. Therefore, the active agent container comprising the injection needle must be prevented from being undesirably pulled forwards. At least one latching tongue prevents the active agent container from being prematurely shifted with respect to the casing, by abutting a flange arranged on a sliding sleeve which accommodates the active agent container. When the auto-injector is placed onto a person'"'"'s skin, a needle protecting tube is shifted into the casing, forcing the latching tongue away from the flange and, thus, freeing the travel path for needle movement.

Claims

1. An injection device comprising:

an elongated casing;

a container carrying an injection needle, said container axially shiftable relative to the casing;

a piston which can be shifted in the container for the purpose of forcing out a substance therein;

a needle protecting tube shiftable relative to the casing; and

a latching member having at least two positions, a latching position wherein the latching member prevents the container from being shifted relative to the casing, and a release position wherein the container is shiftable relative to the casing.

2. The injection device according to claim 1, wherein the needle protecting tube is shiftable generally into and out of the casing and wherein shifting the needle protecting tube into the casing moves the latching member from the latching position to the release position.

3. The injection device according to claim 2, wherein a locking member is provided for locking the needle protecting tube, said locking member locking the needle protecting tube in a position in which it substantially surrounds the injection needle after the injection device has been moved from a point of injection.

4. The injection device as set forth in claim 3, further comprising a needle protecting cap for being attached to the injection device, wherein attached to the injection device, the needle protecting cap substantially encloses the injection needle prior to use prevents the needle protecting tube from being moved into the casing.

5. An auto-injector for automatically injecting an active agent, comprising an elongated casing, an injection needle which can be shifted axially in the casing and connected to an active agent container, a piston which can be shifted in the active agent container for the purpose of delivering the active agent, and a needle protecting tube which can be shifted relative to the casing, wherein, in a latching position, a latching member prevents the active agent container from being shifted with respect to the casing, and wherein that by shifting the needle protecting tube into the casing, the latching member is moved to a released position in which the active agent container is shiftable with respect to the casing.

6. The auto-injector as set forth in claim 5, wherein in the latching position the latching member is locked by the needle protecting tube.

7. The auto-injector as set forth in claim 5, wherein the latching member is formed as at least one elastically flexible latching tongue.

8. The auto-injector as set forth in claim 7, wherein the at least one latching tongue is arranged on a latching sleeve mounted in the casing.

9. The auto-injector as set forth in claim 8, wherein the at least one latching tongue is formed integrally with the latching sleeve.

10. The auto-injector as set in claim 7, wherein the latching tongue prevents the active agent container from being shifted with respect to the casing by abutting a flange arranged on a sliding sleeve which accommodates the active agent container, and wherein as the needle protecting tube is shifted into the casing it forces the latching tongue away from said flange.

11. The auto-injector as set forth in claim 5, wherein in the latching position, the latching member abuts a surface on the sliding sleeve which extends obliquely with respect to the longitudinal axis of the auto-injector, via a surface extending obliquely with respect to the longitudinal axis of the auto-injector.

12. The auto-injector as set forth in claim 11, wherein when the needle protecting tube is shifted into the casing, it releases the latching member and the latching member is forced out of the latching position by advancing the sliding sleeve along the oblique surfaces.

13. The auto-injector as set forth in claim 5, wherein a locking member is provided for latching the needle protecting tube and latches the needle protecting tube in a locked position in which it substantially surrounds the injection needle after the auto-injector has been lifted from a point of injection.

14. The auto-injector as set forth in claim 13, wherein, in the locked position, the needle protecting tube and the active agent container can be shifted together relative to the casing.

15. The auto-injector as set forth in claim 12, wherein the locking member is formed as at least one elastically flexible locking tongue.

16. The auto-injector as set forth in claim 15, wherein the at least one latching tongue and the at least one locking tongue are arranged on the latching sleeve and are formed integrally with the latching sleeve.

17. The auto-injector as set forth in claim 5, further comprising a needle protecting cap for substantially sealing the needle end of the auto-injector prior to use.

18. The auto-injector as set forth in claim 17, wherein the needle protecting cap substantially encloses a portion of the active agent container.

19. The auto-injector as set forth in claim 17, wherein the needle protecting cap is formed such that when attached to the auto-injector, the needle protecting cap prevents the needle protecting tube from being retracted into the casing.

20. The auto-injector as set forth in claim 17, wherein the needle protecting cap comprises an inner sleeve extending over the active agent container and an outer sleeve extending over the needle protecting tube.