INJECTION DEVICE

• US 20090088688A1
• Filed: 03/21/2006
• Published: 04/02/2009
• Est. Priority Date: 04/06/2005
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Cilag Gmbh International (Johnson & Johnson)
• Inventors: David, Edington, Timothy Donald, Barrow-Williams
• Granted Patent: US 8,366,669 B2
• Time in Patent Office: Days
• US Class Current: 604/136
• 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 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 5/326 Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user
• CPC Class Codes: Y10T 29/49904 Assembling a subassembly, then assembling with a second subassembly

Abstract

An injection device (110) comprises a housing (112) adapted to receive a syringe (116) having a discharge nozzle (118) and dispensing piston (114) movable in the syringe to expel the contents of the syringe through the discharge nozzle. There is also a drive (130) adapted to act on the syringe to advance it from a retracted position in which the discharge nozzle is contained within the housing to an extended position in which the discharge nozzle extends from housing. A drive coupling (134) extends from the drive to the dispensing piston of the syringe so as to transfer movement of the drive to the piston. The drive coupling comprises a fixed-length drive-coupling and an interchangeable drive coupling. There is also a method of manufacturing an injection device by assembling a first sub-assembly (210) and second sub-assembly (220).

Claims

1. An injection device comprising:

a housing adapted to receive a syringe having a discharge nozzle and a dispensing piston movable in the syringe to expel the contents of the syringe through the discharge nozzle;

a drive adapted on activation to act on the syringe to advance it from a retracted position in which the discharge nozzle is contained within the housing to an extended position in which the discharge nozzle extends from the housing;

a drive coupling for extending from the drive to the dispensing piston of the syringe so as to transfer movement of the drive to the piston,

characterised in that the drive coupling comprises a fixed-length drive coupling and an interchangeable drive coupling.

2. The injection device of claim 1, wherein the interchangeable drive coupling comprises a rigid member configured to connect with the dispensing piston and with the fixed-length drive coupling.

3. The injection device of claim 2, wherein the rigid member has a longitudinal axis.

4. The injection device of claim 3, wherein the quantity of the contents of the syringe which is expelled in use determines the length of the interchangeable drive coupling along its longitudinal axis.

5. The injection device of claim 4, wherein the length of the interchangeable drive coupling is inversely proportional to the quantity of the contents of the syringe.

6. The injection device of any one of the preceding claims, further comprising:

an interchangeable release element adapted to actuate after a predetermined amount of movement of the piston a delay mechanism in the drive acting on the fixed-length drive coupling.

7. The injection device of claim 6, wherein the interchangeable release element is a constriction adapted to act on at least one arm linking the fixed-length drive coupling to the drive, thereby releasing the drive from the fixed-length drive coupling.

8. The injection device of claim 7, wherein the length of the constriction determines the predetermined amount of movement of the piston.

9. The injection device of claim 8, wherein the length of the constriction is inversely proportional to the quantity of the contents of the syringe.

15. The injection device of any one of the preceding claims, substantially as hereinbefore described with reference to the accompanying drawings.

16. The method of any one of the preceding claims, substantially as hereinbefore described with reference to the accompanying drawings.

10. A method of manufacturing an injection device, comprising:

inserting a syringe having a piston into a first sub-assembly;

inserting an interchangeable drive coupling into the syringe to contact the piston;

providing a second sub-assembly comprising a drive and a fixed-length drive coupling; and

assembling the first sub-assembly and second sub-assembly together,

wherein, on assembly, the fixed-length drive coupling and interchangeable drive coupling communicate in use to transfer movement of the drive to the piston.

11. The method of claim 10, wherein the interchangeable component has a longitudinal axis and comprises a rigid member configured to connect with the piston and with the drive coupling.

12. The method of claim 10 or claim 11, further comprising selecting the interchangeable drive coupling in accordance with its length determined by the quantity of the contents of the syringe.

13. The method of any one of claims 10 to 12, further comprising connecting an interchangeable release element to the first sub-assembly before the step of assembling, wherein the interchangeable release element is adapted to actuate after a predetermined amount of movement of the piston a delay mechanism in the drive acting on the fixed-length drive coupling.

14. The method of any one of claims 10 to 13, further comprising selecting the interchangeable release element in accordance with its length determined by the quantity of the contents of the syringe.