Injection device

Patent metadata

Field	Value
Publication number	US-10130772-B2
Application number	US-201414783483-A
Country	US
Kind code	B2
Filing date	Apr 8, 2014
Priority date	Apr 10, 2013
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A handheld injection device includes a housing, a rotatable dose setting member and a power reservoir coupled to the dose setting member. Energy is stored in the power reservoir during rotation of the dose setting member. The injection device also includes a release member for receiving a force from a user and a rotatably arranged drive member engaging with a drive track of a piston rod. The device further includes a release clutch rotationally constrained to the housing and releasably engaging the drive member. The release clutch is positionable in a first axial position when the release member is in a dose setting position and in a second axial position when the release member is in a dose injection position. The axial position of the drive member within the housing remains constant when the release member is in its dose setting position and in its dose injection position.

First claim

The invention claimed is:

1. A handheld injection device comprising:
a housing;
a piston rod;
a dose setting member rotatable about a longitudinal axis of the housing;
a power reservoir operably coupled to the dose setting member and configured to accumulate energy upon rotation of the dose setting member;
a release member having a surface to receive a force from a finger of a user while the user grips the injection device;
a release clutch rotationally constrained to the housing, the release clutch being positionable in a first axial position when the release member is in a dose setting position and in a second axial position when the release member is in a dose injection position; and
a rotatably arranged drive member releasably engaged by the release clutch and at least partly engaged with a drive track of the piston rod such that the piston rod is rotationally constrained to the drive member, the drive member being configured to release the accumulated energy in the power reservoir when the release clutch is in the second axial position, and the drive member being adapted to rotate the piston rod upon releasing the accumulated energy in the power reservoir,
wherein the drive member is further configured such that an axial position of the drive member within the housing remains constant when the release member is in the dose setting position and when the release member is in the dose injection position.

2. The injection device according to claim 1 , wherein the release clutch comprises at least one tooth or spline configured to engage a corresponding tooth or spline of the drive member when the release member is in the dose setting position.

3. The injection device according to claim 1 , wherein the release clutch comprises a locking arm directly abutting the release member such that the release member entrains the locking arm of the release clutch when the release member is moved to the dose injection position.

4. The injection device according to claim 1 , further comprising a number sleeve directly abutting the release member, wherein the release clutch comprises a locking arm directly abutting the number sleeve such that the release member entrains the number sleeve and the locking arm of the release clutch when the release member is moved to the dose injection position.

5. The injection device according to claim 1 , further comprising a number sleeve connected to the dose setting member such that rotation of the dose setting member causes rotation of the number sleeve, the dose setting member and the number sleeve cooperating to set a dose to be ejected from the injection device,
wherein the number sleeve is adapted to rotate relative to the housing, to remain translationally fixed relative to the housing, and to remain within the housing.

6. The injection device according to claim 1 , wherein the housing comprises a threaded portion cooperating with a threaded outer surface of the piston rod so that rotation of the piston rod relative to the housing axially displaces the piston rod relative to the housing.

7. The injection device according to claim 1 , further comprising a gauge element rotationally constrained to the housing and axially displaceable relative to the housing.

8. The injection device according to claim 7 , further comprising:
a number sleeve connected to the dose setting member such that rotation of the dose setting member causes rotation of the number sleeve, the dose setting member and the number sleeve cooperating to set a dose to be ejected from the injection device,
wherein the gauge element threadedly engages the number sleeve such that rotation of the number sleeve causes an axial displacement of the gauge element relative to the number sleeve and relative to the housing.

9. The injection device according to claim 8 , wherein:
the number sleeve is marked with a sequence of numbers,
the gauge element comprises an aperture, and
the number sleeve is located radially inwards of the gauge element such that at least one of the numbers on the number sleeve is visible through the aperture.

10. The injection device according to claim 1 , wherein the power reservoir comprises a torsion spring configured to be strained upon rotation of the dose setting member.

11. The injection device according to claim 1 , comprising a limiter mechanism defining a maximum settable dose and a minimum settable dose, the limiter mechanism comprising a nut engaged to the drive member via a threaded or splined interface.

12. The injection device according to claim 1 , further comprising a last dose protection mechanism to inhibit setting of an excess dose exceeding an amount of liquid remaining in a cartridge loaded in the housing, the last dose protection mechanism comprising a nut engaged to the drive member via a threaded or splined interface.

13. The injection device according to claim 1 , further comprising a clutch plate arranged between the drive member and the dose setting member, the clutch plate being configured to enable relative rotation between the drive member and the dose setting member during dose setting and being configured to rotationally constrain the drive member and the dose setting member during dose dispensing.

14. The injection device according to claim 1 , further comprising:
a first clicker configured to produce an audible and/or tactile first feedback during dose setting and/or dose dispensing, and
a second clicker configured to produce an audible and/or tactile second feedback during the dose dispensing when the injection device reaches a minimum settable dose position, the second feedback being distinct from the first feedback.

15. The injection device according to claim 1 further comprising a cartridge containing a medicament.

16. The injection device according to claim 1 , wherein the release member is located adjacent to and proximal to the dose setting member.

17. The injection device of claim 1 , wherein the piston rod and the drive member comprise a spline and a groove engaged to one another to prevent relative rotation of the piston rod and the drive member.

18. A drive mechanism for an injection device, the drive mechanism comprising:
a release clutch configured to be rotationally constrained to a housing of the injection device, the release clutch being positionable in a first axial position when a release member of the injection device is in a dose setting position and in a second axial position when the release member of the injection device is in a dose injection position; and
a rotatably arranged drive member releasably engaged by the release clutch and configured to be at least partly engaged with a drive track of an associated piston rod of the injection device such that the associated piston rod is rotationally constrained to the drive member, the drive member being configured to release energy accumulated in a power reservoir of the injection device when the release clutch is in the second axial position, and the drive member being adapted to rotate the associated piston rod upon releasing the accumulated energy in the power reservoir,
wherein the drive member is further configured such that an axial position of the drive member within the housing remains constant when the release member is in the dose setting position and when the release member is in the dose injection position.

19. The drive mechanism according to claim 18 , wherein the release clutch comprises at least one tooth or spline configured to engage a corresponding tooth or spline of the drive member when the re

Assignees

• Sanofi Sa

Inventors

• Butler Joseph
• Jones Matthew
• Plumptre David Aubrey
• Marsh William
• Veasey Robert

Classifications

• A61M2005/3126

  Specific display means related to dosing · CPC title

• A61M5/20 Primary

  Automatic syringes, e.g. with automatically actuated piston rod, with automatic needle injection, filling automatically (A61M5/142 {, A61M5/46} take precedence; {hypodermic projectiles F42B12/54}) · CPC title

• A61M5/3157

  Means providing feedback signals when administration is completed (A61M5/20 takes precedence) · CPC title

• A61M5/31553

  without axial movement of dose setting member · CPC title

• A61M2205/582

  by tactile feedback · CPC title