MULTI-STROKE DELIVERY PUMPING MECHANISM FOR A DRUG DELIVERY DEVICE FOR HIGH PRESSURE INJECTIONS

• US 20120004639A1
• Filed: 12/08/2009
• Published: 01/05/2012
• Est. Priority Date: 12/09/2008
• Status: Active Grant

• Current Assignee: Becton, Dickinson & Co
• Original Assignee: Becton, Dickinson & Co
• Inventors: Schoonmaker, Ryan, Bruehwiler, Michel, Rosen, Melissa, Ira, Spool
• Granted Patent: US 9,238,112 B2
• Time in Patent Office: Days
• US Class Current: 604/506
• CPC Class Codes: A61M 2005/3128 Incorporating one-way valves, e.g. pressure-relief or non-return valves
• CPC Class Codes: A61M 2005/31518 designed to reduce the overall size of an injection device, e.g. using flexible or pivotally connected chain-like rod members
• CPC Class Codes: A61M 2005/3152 including gearings to multiply or attenuate the piston displacing force
• CPC Class Codes: A61M 5/14216 Reciprocating piston type
• CPC Class Codes: A61M 5/204 connected to external reservoirs for multiple refilling
• CPC Class Codes: A61M 5/286 upon internal pressure increase, e.g. pierced or burst A61M5/283 takes precedence
• CPC Class Codes: A61M 5/3146 Priming, e.g. purging, reducing backlash or clearance
• CPC Class Codes: A61M 5/31511 Piston or piston-rod constructions, e.g. connection of piston with piston-rod A61M5/5066 takes precedence
• CPC Class Codes: A61M 5/31553 without axial movement of dose setting member
• CPC Class Codes: A61M 5/3158 performed by axially moving actuator operated by user, e.g. an injection button
• CPC Class Codes: A61M 5/48 having means for varying, regulating, indicating or limiting injection pressure A61M5/142 takes precedence ; monitoring pressure in infusion systems A61M5/16854

Abstract

A dual-chambered drug delivery device (201) includes a cartridge (211) having a first chamber (212) for storing a medicament and a second chamber (211) in fluid communication with the first chamber (212). A dose setting member (241) is used to set a medicament dose to be injected at an injection site. A piston (281) is disposed in the second chamber (221). An upward stroke of the piston (281) draw a portion of the medicament dose into the second chamber (221) and a downward stroke of the piston (281) expels the portion of the medicament dose. A needle (205) communicates with the second chamber (221) for sequentially injecting the portions of the medicament dose into the injection site.

Claims

1. A dual-chambered drug delivery device, comprising:

a cartridge having a first chamber for storing a medicament;

a second chamber in fluid communication with said first chamber;

a dose setting member for setting a medicament dose to be injected at an injection site;

a piston disposed in said second chamber, an upward stroke of said piston drawing a portion of the medicament dose into said second chamber and a downward stroke of said piston expelling the portion of the medicament dose; and

a needle communicating with said second chamber for sequentially injecting portions of the medicament dose into the injection site.

2. The dual-chambered drug delivery device according to claim 1, wherein

a drive screw is movably connected to said dose setting member such that rotation of said dose setting member moves said drive screw upwardly.

3. The dual-chambered drug delivery device according to claim 2, wherein

a bevel gear is rotatably connected to said dose setting member such that downward movement of said drive screw rotates said dose setting member, which rotates said bevel gear;

and

a piston is movably connected to said bevel gear.

4. The dual-chambered drug delivery device according to claim 3, wherein

a clutch is connected to said dose setting member, said clutch separating said dose setting member from said bevel gear when the medicament dose is being set and engaging said dose setting member and said bevel gear when said medicament dose is being delivered.

5. The dual-chambered drug delivery device according to claim 2, wherein

a dose tracking nut is disposed on said drive screw to prevent further medicament doses from being set when the remaining medicament in said first chamber is less than a predetermined amount.

6. The dual-chambered drug delivery device according to claim 2, wherein

a rack is movably connected to said drive screw such that downward movement of said drive screw during the medicament dose injection rotates said rack.

7. The dual-chambered drug delivery device according to claim 6, wherein said rack is circular.

8. The dual-chambered drug delivery device according to claim 6, wherein

a cam gear is rotatably connected to said rack such that rotation said rack rotates said cam gear, said cam gear being fixed to a cam wheel;

and

a piston is movably connected to said cam wheel such that rotation of said cam wheel reciprocatingly drives said piston.

9. The dual-chambered drug delivery device according to claim 6, wherein

a dose tracking nut is disposed on said rack is disposed on said drive screw to prevent further medicament doses from being set when the remaining medicament in said first chamber is less than a predetermined amount.

10. A dual-chambered drug delivery device, comprising:

a cartridge having a first chamber for storing a medicament;

a second chamber in fluid communication with said first chamber;

a dose setting member for setting a medicament dose to be injected at an injection site;

a needle communicating with said second chamber for sequentially injecting portions of the medicament dose into the injection site;

a ratchet movable between a first position and a second position by rotation of said dose setting member, said second position corresponding to the medicament dose being set; and

a rack movable by said ratchet when said ratchet is moved from said second position to said first position.

11. The dual-chambered drug delivery device according to claim 10, wherein

said rack has a movable rack member and a carriage, said movable rack position having a first position and a second position, said movable rack member moving said carriage when said movable rack member is in said second position.

12. The dual-chambered drug delivery device according to claim 11, wherein

said movable rack member moves up a ramp to move from said first position to said second position.

13. The dual-chambered drug delivery device according to claim 12, wherein

when said carriage engages teeth connected to said ratchet, further medicament doses are prevented from being set.

14. The dual-chambered drug delivery device according to claim 12, wherein

said rack is connected to a cam wheel, such that movement of said rack rotates said cam wheel.

15. The dual-chambered drug delivery device according to claim 14, wherein

said cam wheel is connected to a piston such that rotation of said cam wheel reciprocatingly moves said piston, an upward stroke of said piston draws a portion of the medicament dose into said second chamber from said first chamber and a downward stroke of said piston expels the portion of the medicament dose.

16. The dual-chambered drug delivery device according to claim 12, wherein

said cartridge is pressurized by a compression spring engaging a stopper disposed in said cartridge.

17. A method of injecting medicament using a dual-chambered drug delivery device, comprising the steps of:

storing a medicament in a first chamber;

setting a medicament dose;

transferring a portion of the medicament dose from the first chamber to a second chamber;

injecting the portion of the medicament dose from the second chamber into an injection site; and

repeating the injecting of portions of the medicament dose until the entire medicament dose is injected.

18. The method of injecting medicament using a dual-chambered drug delivery device according to claim 17, wherein

the injecting of a portion of the medicament dose and the repeating thereof is accomplished by one stroke of an injection rod.

19. The method of injecting medicament using a dual-chambered drug delivery device according to claim 17, further comprising

tracking the amount of the medicament stored in the first chamber.

20. The method of injecting medicament using a dual-chambered drug delivery device according to claim 19, further comprising

preventing the medicament dose from being set when the stored medicament being tracked is less than a predetermined amount.