Medical Injection Device

Patent metadata

Field	Value
Publication number	US-2016106920-A1
Application number	US-201414895155-A
Country	US
Kind code	A1
Filing date	May 27, 2014
Priority date	Jun 3, 2013
Publication date	Apr 21, 2016
Grant date	—

Abstract

The present invention relates to a medicament injection device ( 100 ) that comprises a housing ( 110, 120 ) and an actuator ( 400, 500 ) configured for expelling medicament from a held reservoir ( 200 ) through an injection needle ( 250 ). A needle shield ( 150 ) is movable from a distal position through an intermediary position and further proximally to activate dose expelling. A carrier ( 300 ) movable within the housing ( 110, 120 ) holds the injection needle ( 250 ). A detent mechanism couples carrier ( 300 ) with the needle shield ( 150 ) as the needle shield ( 150 ) moves from the distal to the intermediary position. When the needle shield is moved further proximally the detent mechanism decouples the carrier ( 300 ) from the needle shield ( 150 ). A carrier spring device ( 680 ) is arranged between the housing ( 110, 120 ) and the carrier ( 300 ). The injection device ( 100 ) provides increased safety against potential damage to the injection needle ( 150 ) in case the injection device ( 100 ) is dropped on a hard surface.

First claim

1 . An injection device for administering a dose of a medicament from a held medicament reservoir, the injection device comprising:
a housing defining distal and proximal ends, an injection needle arranged at the distal end of the housing and adapted for fluid communication with a held medicament reservoir, a needle shield disposed at the distal end of the housing, the needle shield being movable proximally relative to the housing upon exertion of an externally applied force to gradually expose the injection needle as the needle shield moves proximally relative to the housing, and an actuator configured to act on the medicament reservoir to expel a dose of medicament therefrom,
wherein the injection device further comprises:
a carrier that is movable relative to the housing from a distal position to a proximal position, the carrier holding the injection needle and the medicament reservoir,
a carrier spring device arranged between the housing and the carrier, the carrier spring device being configured to force the carrier in the distal direction, and
a detent mechanism arranged between the carrier and the needle shield, wherein the detent mechanism is configured to:
couple axial movement of the needle shield with axial movement of the carrier as the needle shield moves proximally relative to the housing from a distal position to an intermediary position so that the injection needle is maintained in a shielded state, and
allow relative axial movement between the needle shield and the carrier as the needle shield moves relative to the housing from the intermediary position and into a proximal position so that the injection needle is gradually exposed as the needle shield (M) moves relative to housing between the intermediary position and the proximal position.

2 . The injection device as defined in claim 1 , wherein the detent mechanism is configured to prevent relative axial movement between the carrier and the needle shield when the needle shield is positioned between the distal position and the intermediary position.

3 . The injection device as defined in claim 1 , wherein the detent mechanism is coupled to the needle shield and the carrier to lock the carrier relative to the needle shield and wherein a carrier control member is arranged to cooperate with the housing so that relative movement between the needle shield and the housing acts to release said lock upon the needle shield entering into the intermediary position.

4 . The injection device as defined in claim 1 , wherein the needle shield is positionable relative to the housing into a trigger position, the trigger position being located proximally to said intermediary position, wherein the actuator is maintained in an inactive state when the needle shield is positioned distally relative to the trigger position, and wherein the actuator is released from said inactive state when the needle shield is moved proximally into the trigger position.

5 . The injection device ( 100 ) as defined in claim 1 , wherein the needle shield is so configured that movement of the needle shield acts to release the actuator in a state where relative movement between the needle shield and the carrier has shifted the injection needle into the state where the injection needle is exposed.

6 . The injection device as defined in claim 1 , wherein the actuator comprises a drive spring configured for forwarding load of the drive spring to the piston of the medicament reservoir to expel a dose of a drug medicament from the medicament reservoir upon release of the actuator.

7 . The injection device as defined in claim 1 , wherein a needle shield spring device is coupled to the needle shield and configured to bias the needle shield towards its distal position.

8 . The injection device as defined in claim 1 , wherein an impact damper is arranged between the housing and the carrier, the impact damper being configured to dampen motion of the carrier relative to the housing.

9 . The injection device as defined in claim 8 , wherein the impact damper is configured as a damper mechanism incorporating one or more damper mechanisms selected from the group consisting of a hydraulic damper, a pneumatic damper, a grease damper, a rotational motion damper and a foam damper.

10 . The injection device as defined in claim 1 , wherein the medicament reservoir defines an elongated reservoir body, wherein an injection needle is mounted on said reservoir body at a distal end thereof and wherein a slideable piston is arranged within the reservoir body to be driveable in the distal direction to expel medicament from the medicament reservoir.

11 . The injection device as defined in claim 1 , wherein the medicament reservoir, in a situation of use, is fixedly mounted relative to the carrier.

12 . The injection device as defined in claim 1 , wherein the medicament reservoir defines a medicament cartridge having an elongated cartridge body, wherein a cartridge septum seals the distal end of cartridge body, the cartridge septum configured for being pierced by the injection needle for establishing fluid communication with medicament contained in the medicament cartridge and wherein a slideable piston is arranged within the cartridge body to be driveable in the distal direction to expel medicament from the medicament cartridge.

13 . The injection device as defined in claim 12 , wherein the injection needle defines a front needle for penetrating the skin of a subject user and a rear needle for piercing the cartridge septum, the front needle and rear needle being configured for fluid communication, and wherein the injection needle is mounted fixedly relative to the carrier to be moveable together with the carrier.

14 . The injection device as defined in claim 13 , wherein the medicament cartridge is arranged within the carrier so that, prior to triggering of the injection device, the rear needle is separated axially from the cartridge septum.

15 . The injection device as defined in claim 14 , wherein the medicament cartridge is arranged slideable within the carrier so that when the actuator acts on the medicament cartridge, the medicament cartridge initially slides relative to the carrier so that the cartridge septum is pierced by the rear needle and subsequently the piston is driven by the actuator in the distal direction relative to the cartridge body 1210 to expel medicament from the medicament cartridge.

Assignees

• Novo Nordisk As

Inventors

• Stefansen Mads Schenstroem

Classifications

• A61M5/326

  Fully automatic sleeve extension, i.e. in which triggering of the sleeve does not require a deliberate action by the user · CPC title

• A61M5/3245

  Constructional features thereof, e.g. to improve manipulation or functioning · CPC title

• A61M5/3287

  Accessories for bringing the needle into the body; Automatic needle insertion (A61M5/20, A61M5/31525 take precedence) · CPC title

• A61M5/2033 Primary

  Spring-loaded one-shot injectors with or without automatic needle insertion (multishot dosing syringes A61M5/31525, needle insertion only A61M5/3287) · CPC title

• A61M2005/2013

  triggering of discharging means by contact of injector with patient body · CPC title