Impulse chamber for jet delivery device

• US 20070049864A1
• Filed: 05/24/2006
• Published: 03/01/2007
• Est. Priority Date: 11/27/2003
• Status: Active Grant

• Current Assignee: Semikron Elektronik GmbH & Company KG (Heilbronner Holding GbR), Novo Nordisk A/S
• Original Assignee: Novo Nordisk A/S
• Inventors: Hansen, Torben
• Granted Patent: US 8,608,684 B2
• Time in Patent Office: Days
• US Class Current: 604/68
• CPC Class Codes: A61M 2005/3128 Incorporating one-way valves, e.g. pressure-relief or non-return valves
• CPC Class Codes: A61M 5/204 connected to external reservoirs for multiple refilling
• 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 5/282 by compression of deformable ampoule or carpule wall
• CPC Class Codes: A61M 5/30 Syringes for injection by jet action, without needle, e.g. for use with replaceable ampoules or carpules

Abstract

The invention provides a jet expelling assembly comprising a reservoir and an impulse chamber assembly. The impulse chamber assembly comprises a chamber portion defining a cavity having a general axis, a piston received in the cavity along the general axis and comprising a fluid inlet, thereby defining a variable-volume impulse chamber with an outlet nozzle. The inlet comprises a conduit adapted to slidably engage a reservoir outlet during relative movement therebetween. The chamber portion is arranged stationary relative to the reservoir, whereby expelling an amount of drug from the reservoir to the impulse chamber via the inlet causes the piston to move towards the reservoir, the impulse chamber thereby receiving the expelled amount of drug.

Claims

1. A jet expelling assembly, comprising:

a housing,

a reservoir (30, 420) adapted to contain a fluid drug and comprising an outlet, and

an impulse chamber assembly comprising;

a chamber portion (11, 431) defining a cavity having a general axis,

a piston (20, 433) slidably received in the cavity along the general axis and comprising a fluid inlet, the cavity and the piston in combination defining a variable-volume impulse chamber (18, 436), the inlet comprising a generally straight conduit (23, 435) protruding from the piston and arranged generally in parallel with the general axis, the conduit being adapted to slidably engage the reservoir outlet during relative movement therebetween, and

a fluid outlet nozzle (16, 432) in fluid communication with the impulse chamber,

wherein the chamber portion is arranged stationary relative to the reservoir, and

wherein expelling an amount of drug from the reservoir to the impulse chamber via the inlet causes the piston to move towards the reservoir, the impulse chamber thereby receiving the expelled amount of drug.

2. A jet expelling assembly as in claim 1, wherein the conduit is arranged generally co-axially with the general axis.

3. A jet expelling assembly as in claim 12, wherein the fluid outlet nozzle is arranged generally in parallel with the general axis.

4. A jet expelling assembly as claim 1, wherein the reservoir outlet comprises a self-sealing septum (32, 423), the conduit comprising a pointed proximal end adapted to penetrate the self-sealing septum.

5. A jet expelling assembly as in claim 4, wherein the conduit is formed integrally with the piston.

6. A jet expelling assembly as in claim 1, wherein the fluid inlet comprises a uni-directional inlet valve, a constriction (434) or a tortuous path portion.

7. A jet expelling assembly as in claim 1, wherein the fluid outlet nozzle comprises a pointed hollow needle (216) adapted to penetrate a superficial layer of the skin of a user.

8. A jet expelling assembly as in claim 1, further comprising an expelling assembly (440) for expelling an amount of drug from the reservoir to the impulse chamber via the fluid inlet thereby expanding the impulse chamber, and an impulse generating assembly (450) adapted to actuate the piston to thereby reduce the volume of the impulse chamber, thereby expelling an amount of drug through the outlet nozzle.

9. A jet expelling assembly as in claim 8, wherein the fluid outlet nozzle is adapted to be arranged against the skin of a subject, the impulse generating assembly being adapted to create a force for injecting the liquid drug from said impulse chamber, through the outlet nozzle and into the subject through the skin.

10. A jet expelling assembly as in claim 9, further comprising a drive assembly for reducing the volume of the impulse chamber with a reduced force relative to the impulse generating assembly when a portion of the drug has been expelled by the impulse generating assembly.

11. A jet expelling assembly as in claim 10, further comprising a dose setter for selectable setting a dose of drug to be expelled and transfer that amount of drug to the impulse chamber, an actuator for actuating the impulse generating assembly and the drive assembly, and an actuatable release, wherein actuation of the release causes the impulse generating assembly to expel a portion of the set dose from the impulse chamber at a high pressure through the outlet nozzle, followed by subsequent expelling of the remaining portion of the set dose from the impulse chamber through the outlet nozzle by means of the drive assembly.

12. A jet expelling assembly as in claim 8, wherein the impulse generating assembly comprises a coil spring (90, 452) arranged substantially axially relative to the general axis.

13. A jet expelling assembly as in claim 8, wherein the fluid inlet is an open communication allowing an amount of drug to be forced backwardly into the reservoir during expelling of drug from the impulse chamber, the flow resistance of the outlet nozzle, the flow resistance of the fluid inlet and the impulse generating assembly being configured to allow a backflow selected from the group of ranges consisting of less than 15%, less than 10%, less than 5% and less than 1%.

14. A jet expelling assembly as in claim 1, wherein the impulse chamber assembly is releasably attached relative to the housing.

15. A jet expelling assembly as claim 1, wherein the reservoir is releasably attached relative to the housing.

16. A jet expelling assembly as in claim 1, wherein the reservoir has a general columnar configuration with a longitudinal axis arranged generally in parallel with the axis defined by the movement of the piston.

17. A method for expelling an amount of drug, comprising the steps of:

providing a jet expelling assembly comprising a drug reservoir with an outlet, a variable-volume impulse chamber with an axially displaceable piston, the piston comprising an inlet in sliding engagement with the reservoir outlet, and a nozzle in fluid communication with the impulse chamber,

expelling an amount of drug from the reservoir to the impulse chamber thereby moving the piston relative to the reservoir and the nozzle.

18. A method as in claim 17, comprising the further step of:

moving the piston relative to the reservoir and the nozzle to thereby expel an amount of drug from the impulse chamber through the nozzle.