Safety mechanism for a medicament delivery device and a medicament delivery device comprising the same

Patent metadata

Field	Value
Publication number	US-11141533-B2
Application number	US-201716070615-A
Country	US
Kind code	B2
Filing date	Jan 20, 2017
Priority date	Feb 24, 2016
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

The present disclosure relates to a safety mechanism for a medicament delivery device for mechanical shock absorption, which safety mechanism has a medicament delivery member sleeve, a housing having a proximal opening arranged to receive the medicament delivery member sleeve, wherein the medicament delivery member sleeve is axially displaceable inside the housing, between an extended position in which a proximal end portion of the medicament delivery member sleeve extends proximally from the housing and a retracted position in which the proximal end portion is received by the housing, wherein the proximal end portion has a resilient structure, enabling compression of the proximal end portion in the distal direction upon impact of an axial force greater than a threshold value.

First claim

The invention claimed is:

1. A safety mechanism for a medicament delivery device for mechanical shock absorption, which safety mechanism comprises:
a medicament delivery member sleeve comprising a proximal end portion having a generally cylindrical shape with a proximal end face,
a housing having a longitudinal axis and a proximal opening arranged to receive the medicament delivery member sleeve,
wherein the medicament delivery member sleeve is axially displaceable inside the housing, between an extended position in which the proximal end portion of the medicament delivery member sleeve extends proximally from the housing to allow the proximal end face to contact an injection site, and a retracted position in which the proximal end portion is received by the housing,
wherein the proximal end portion has a resilient structure that expands radially outward relative to the longitudinal axis when the proximal end portion is compressed in the distal direction upon impact of an axial force greater than a threshold value.

2. The safety mechanism as claimed in claim 1 , wherein the proximal end portion is arranged to expand radially upon compression, to a radial dimension greater than the corresponding dimension of the proximal opening.

3. The safety mechanism as claimed in claim 1 , wherein the proximal end portion is tubular and has a weakened sidewall.

4. The safety mechanism as claimed in claim 3 , wherein the weakened sidewall comprises through-openings extending in the peripheral direction.

5. The safety mechanism as claimed in claim 4 , wherein the through-openings extend along a majority of the periphery of the proximal end portion.

6. The safety mechanism as claimed in claim 4 , wherein the through-openings form a system of through-opening configured to enable axial deformation of the medicament delivery member sleeve.

7. The safety mechanism as claimed in claim 6 , wherein the system of through-openings includes two oppositely arranged central through-openings, and a first pair and a second pair of elongated through-openings, each of the first pair and the second pair of elongated through-opening being axially displaced relative to each other, mirrored in a radial plane, on opposite sides of the central through-openings, wherein the first pair and the second pair of through-openings are mirrored in an axial plane.

8. The safety mechanism as claimed in claim 1 , wherein the medicament delivery member sleeve is arranged to elastically deform upon compression and radial expansion.

9. The safety mechanism as claimed in claim 1 , wherein the medicament delivery member sleeve is arranged to plastically deform upon compression and radial expansion.

10. The safety mechanism as claimed in claim 1 , further comprising:
a container driver locking member rotatable from a first rotational position to a second rotational position, and
a first energy accumulating member arranged to bias the medicament delivery member sleeve in the proximal direction,
wherein the medicament delivery member sleeve and the container driver locking member are configured such that linear motion of the medicament delivery member sleeve from the extended position to the retracted position is transformed into rotational motion of the container driver locking member from the first rotational position to the second rotational position,
wherein the container driver locking member is configured to allow the medicament delivery member sleeve to return to the extended position, and to restrict movement of the medicament delivery member sleeve when the container driver locking member is in the second rotational position.

11. The safety mechanism as claimed in claim 1 , further comprising:
a proximal flange provided at the proximal end of the medicament delivery member
sleeve, which proximal flange has a first radially flexible arm extending longitudinally in the distal direction, and wherein the housing has a proximal portion arranged between the first radially flexible arm and the outer surface of the medicament delivery member sleeve when the medicament delivery member sleeve is displaced from the extended position to the retracted position,
a cover having a distal opening forming a channel arranged to receive the medicament delivery member sleeve and the housing, wherein the channel is dimensioned such that, when the housing is received by the cover, there is a radial distance between the inner surface of the cover and the outer surface of the proximal portion which is less than a radial dimension D of the first radially flexible arm, preventing the medicament delivery member sleeve from obtaining its retracted position.

12. The safety mechanism as claimed in claim 11 , wherein the first radially flexible arm is arranged to bear against the outer surface of the proximal portion in the retracted position.

13. The safety mechanism as claimed in claim 11 , wherein the proximal flange has a body, wherein the first radially flexible arm extends from the body, from a radial distance corresponding to the radial dimension of the outer surface of that portion of the proximal end of the housing which is axially aligned with the first radially flexible arm.

14. The safety mechanism as claimed in claim 11 , wherein the first radially flexible arm is inclined relative to the central axis of the medicament delivery member sleeve.

15. A medicament delivery device comprising the safety mechanism as claimed in claim 1 .

16. A safety mechanism for a medicament delivery device, which safety mechanism comprises:
a medicament delivery member sleeve comprising a proximal end portion having a generally cylindrical shape with a proximal end face,
a housing having a proximal opening arranged to receive the medicament delivery member sleeve,
wherein the medicament delivery member sleeve is axially displaceable inside the housing between an extended position where the proximal end portion of the medicament delivery member sleeve extends proximally from the housing to allow the proximal end face to contact an injection site, and a retracted position where the proximal end portion is received by the housing,
wherein the proximal end portion has a resilient structure comprising a diameter and a weakened side wall.

17. The safety mechanism of claim 16 , where the weakened side wall is compressed by an axial impact force in a distal direction.

18. The safety mechanism of claim 17 , where the compression of the weakened side wall causes an increase in diameter of the resilient structure such that the medicament delivery sleeve cannot retract distally into the proximal opening of the housing.

19. The safety mechanism of claim 16 , wherein the weakened sidewall comprises through-openings extending in the peripheral direction.

20. The safety mechanism of claim 16 further comprising, a cover attached to the housing; and
a proximal flange positioned within the cover, where the proximal flange has a radially flexible arm that fits within a channel between the cover and the medicament delivery sleeve such that distal axial movement of the medicament delivery member sleeve is prevented by a wedging of the radially flexible arm between the cover and the housing.

Assignees

• Carebay Europe Ltd
• Shl Medical Ag

Inventors

• Olson Stephan

Classifications

• A61M2005/206

  With automatic needle insertion · CPC title

• A61M2005/2013

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

• A61M5/31583

  based on rotational translation, i.e. movement of piston rod is caused by relative rotation between the user activated actuator and the piston rod · CPC title

• A61M5/3202 Primary

  Devices for protection of the needle before use, e.g. caps (A61M5/50 takes precedence; for infusion spikes A61M5/1626; protectors for sharps A61B50/3001) · CPC title

• A61M5/31571 Primary

  Means preventing accidental administration (for automatic syringes A61M5/20) · CPC title