AUTOINJECTORS

• US 20130218128A1
• Filed: 09/13/2011
• Published: 08/22/2013
• Est. Priority Date: 09/21/2010
• Status: Active Grant

• Current Assignee: Owen Mumford
• Original Assignee: Owen Mumford
• Inventors: Cowe, Toby
• Granted Patent: US 9,814,836 B2
• Time in Patent Office: Days
• US Class Current: 604/506
• 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 2005/2407 from the rear
• CPC Class Codes: A61M 2005/2411 from the front
• CPC Class Codes: A61M 2005/3247 Means to impede repositioning of protection sleeve from needle covering to needle uncovering position
• 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 5/24 Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic ampoules or carpules A61J1/06
• CPC Class Codes: A61M 5/31583 based on rotational translation, i.e. movement of piston rod is caused by relative rotation between the user activated actuator and the piston rod
• CPC Class Codes: A61M 5/3204 Needle cap remover, i.e. devices to dislodge protection cover from needle or needle hub, e.g. deshielding devices
• 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

An autoinjector includes a housing for receiving in use in a generally longitudinal loading direction a syringe assembly including a syringe carrier and a syringe, the syringe including a syringe body having a slideable internal piston for expressing a dose contained in the body through a needle at a forward end thereof; a drive mechanism for providing drive for operation of the autoinjector and being disposed generally within the housing and including a mechanical energy source and a winder element for being rotated to charge the energy source, and an input transmission train operational between the syringe assembly and the winder element in use, whereby loading of the syringe assembly into the housing rotates the winder element to charge the energy source.

Claims

1. An autoinjector comprising:

a housing for receiving in use in a generally longitudinal loading direction a syringe assembly comprising a syringe carrier and a syringe, the syringe including a syringe body having a slideable internal piston for expressing a dose contained in the body through a needle at a forward end thereof;

a drive mechanism for providing drive for operation of the autoinjector and being disposed generally within said housing and including a mechanical energy source and a winder element for being rotated to charge the energy source, and

an input transmission train operational between the syringe assembly and the winder element in use, whereby loading of said syringe assembly into said housing rotates said winder element to charge the energy source.

2. An autoinjector according to claim 1, wherein said housing includes a passage for receiving in use said syringe assembly.

3. An autoinjector according to claim 2, wherein in use said syringe assembly is inserted forwardly with said passage through a rear end.

4. An autoinjector according to claim 2, wherein in use said syringe assembly is inserted rearwardly into said passage through a front end.

5. An autoinjector according to claim 1, wherein said input transmission train includes a screw element mounted for rotation and engaged by a complementary element that moves linearly in use upon insertion of said syringe assembly into said housing, whereby linear movement of said screw element induces rotation of said screw element.

6. An autoinjector according to claim 5, wherein said complementary element is drivingly connected directly or indirectly to said winder element.

7. An autoinjector according to claim 5, wherein said complementary element is a part of said winder element.

8. An autoinjector according to claim 1, wherein said energy source includes a torsion spring.

9. An autoinjector according to claim 1, wherein said energy source includes a constant torque spring.

10. An autoinjector according to claim 1, including an output transmission train operational between said rotary energy source and said syringe piston, which includes at least some different component elements from said input transmission train.

11. An autoinjector according to claim 10, wherein the overall mechanical advantage of the combined input and output transmission trains is non-unity.

12. An autoinjector according to claim 11, wherein said mechanical advantage is greater than unity.

13. An autoinjector according to claim 1, wherein the input transmission train includes a tooth element for moving linearly in use with the syringe assembly and engaged in a helical thread.

14. An autoinjector according to claim 1 dependent thereon, wherein upon loading of the syringe assembly in use into the autoinjector, the input transmission train is interrupted before said output transmission train becomes operational.

15. An autoinjector according to claim 1, wherein said syringe assembly includes a removable needle shield initially engaging the syringe to cover the syringe needle, and a needle shield remover for being moved to remove said needle shield upon loading of the syringe assembly into the autoinjector.

16. An autoinjector according to claim 1, wherein said drive mechanism includes a rotary to linear motion converter for applying linear drive to said syringe piston, and converter including a threaded element having a thread of non-uniform pitch.

17. An autoinjector comprising:

a housing for receiving in use in a generally longitudinal loading direction a syringe assembly comprising a syringe carrier and a syringe, the syringe including a syringe body having a slideable internal piston for expressing a dose contained in the body through a needle at a forward end thereof;

a drive mechanism for providing drive for operation of the autoinjector and being disposed generally within said housing and including a mechanical energy source and a charger element for being moved to charge the mechanical energy source;

an input transmission coupling operational between the syringe assembly and charger element in use whereby loading of said syringe assembly into said housing moves said charge element to charge said source, and

an output transmission train operational between the energy source and said drive mechanism,

wherein said input transmission train and said output transmission train include at least some different component elements.

18. An autoinjector comprising a reusable housing for receiving a syringe assembly, of the type including a syringe with a removable needle shield, the housing including a drive mechanism for providing drive for operation of the autoinjector and including a mechanical energy source, the autoinjector being adapted so that loading of the syringe assembly into the housing charges said mechanical energy source and initiates removal of said needle shield.

19. An autoinjector comprising:

a housing containing a drive mechanism and adapted in use to provide drive motion to a syringe assembly via a drive train including a gear train, wherein one of the gears in the gear train is mounted on a shaft for movement between;

a) a ratchet position in which the gear is constrained to allow rotation in a single direction only

b) a braking position where a variable retarding friction force is applied to the gear wheel, and

c) a release position in which the gear wheel may rotate generally freely.

20. A syringe assembly comprising a housing generally containing a syringe, and a resiliently biased syringe needle shield adapted to lock out in a needle shielding position upon completion of an injection.

21. A syringe assembly comprising a syringe housing generally containing a syringe, and a plunger device threadedly engaged with said syringe housing whereby rotation of the plunger relative to the housing moves the plunger forwardly into the syringe.

22. A syringe shield formed of moulded plastics material, having first and second generally cylindrical portions bridged by an integral resiliently compressible and/or extendable portion, the device being adapted to receive in use a syringe.

23. An autoinjector comprising a housing for being loaded with a syringe assembly including a removable needle shield, at least one of the autoinjector and the syringe assembly being adapted so that loading of said syringe assembly into said autoinjector initiates removal of said needle shield.

24. An autoinjector according to claim 23, wherein said housing includes an abutment surface for directly or indirectly engaging said needle shield to initiate removal.

25. An autoinjector according to claim 23, wherein said syringe assembly comprises a generally cylindrical container containing a syringe, and the autoinjector housing comprises a complementary generally cylindrical recess into which said syringe assembly is loaded longitudinally.

26. A method of autoinjection which comprises inserting a disposable syringe assembly into an autoinjector main unit to thereby charge a mechanical energy source within said unit and thereafter releasing said energy source to effect autoinjection.