US-12623032-B2 - Safety device for shielding an injection needle of a medical container, and an injection device including this safety device

US12623032B2US 12623032 B2US12623032 B2US 12623032B2US-12623032-B2

Abstract

A safety device includes a tubular body, a needle cover, a release element, and a retainer. The tubular body extends along a longitudinal axis and is configured to receive a medical container. The needle cover is movable relative to said body between a retracted position and a distally extended position to shield the injection needle after activation of the safety device. The release element is configured to move the needle cover from the retracted to the extended position. The retainer is configured to transmit a user's activation force to the needle cover once the injection operation is completed. The needle cover includes a distal abutment surface abutting against a proximal abutment surface of a bump protruding from the body in the retracted position. The body has a first axial slot extending from a distal end of the body, and the bump is circumferentially distant from said first axial slot.

Inventors

Michael Fiard
Henry-Gilles Chaniol
Gregory Peruzzo

Assignees

BECTON DICKINSON FRANCE

Dates

Publication Date: 20260512
Application Date: 20221223
Priority Date: 20211224

Claims (15)

1 . A safety device for mounting onto a medical container provided with a flange and an injection needle, the safety device comprising: a tubular body extending along a longitudinal axis, the tubular body being configured to receive the medical container, a needle cover movable relative to said body between a retracted position, and an extended position in which the needle cover distally extends from the retracted position in order to shield the injection needle after activation of the safety device, a release element configured to move the needle cover from the retracted position to the extended position after activation of the safety device, a retainer, the retainer being configured to transmit an activation force applied to the retainer in a distal axial direction to the needle cover once an injection operation is completed, such that the activation force transmitted to the needle cover causes the needle cover to move from the retracted position to the extended position, wherein the needle cover comprises a distal abutment surface, said distal abutment surface abutting against a proximal abutment surface of a bump protruding from a distal portion of the body in the retracted position of the needle cover, and wherein the body has a first axial slot extending from a distal end of the body, the first axial slot has a proximal end, said proximal end being proximally located with regard to the bump, and the bump is circumferentially distant from said first axial slot.
2 . The safety device of claim 1 , wherein the distance between the bump and the first axial slot is defined by a central angle comprised between 5°-13°.
3 . The safety device of claim 1 , wherein the bump comprises two bumps and the first axial slot extends between the two bumps of the body, each of said two bumps being circumferentially distant from said first axial slot.
4 . The safety device of claim 1 , wherein at least one of the proximal abutment surface and the distal abutment surface comprises a chamfer configured to ease passage of the needle cover over the bump when the needle cover moves distally to the extended position.
5 . The safety device of claim 1 , wherein the distal abutment surface is located on a reduced thickness portion of the needle cover.
6 . The safety device of claim 1 , wherein the distal abutment surface of the needle cover is located on a radial protrusion of the needle cover, and the radial protrusion has reinforcing means configured to reinforce a proximal side of this radial protrusion.
7 . The safety device of claim 1 , wherein the bump has a cantilevered portion.
8 . The safety device of claim 1 , wherein the body has the first axial slot and a second axial slot, the first axial slot and the second axial slot extending on both sides of the bump.
9 . The safety device of claim 1 , wherein the bump extends in a circumferential direction according to a central angle comprised between 22.5°-45°.
10 . The safety device of claim 1 , wherein the bump of the body has a first end provided with a chamfer extending in a circumferential direction.
11 . The safety device of claim 1 , wherein the bump of the body has a first end, an opposite second end, and a decreasing height from said second end to said first end.
12 . The safety device of claim 1 , wherein the bump comprises only two bumps.
13 . The safety device of claim 1 , wherein the bump has a first end and an opposite second end, and the proximal abutment surface of said bump has a ramp portion, said ramp portion having a decreasing slope towards the first end of said bump.
14 . The safety device of claim 1 , wherein the body has the first axial slot extending from a distal end of said body, the first axial slot having a predetermined length comprised between 1 mm-6 mm.
15 . An injection device comprising a medical container having an injection needle and the safety device of claim 1 , said safety device being mounted onto said medical container.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to European Patent Application No. 21306937.0 filed Dec. 24, 2021, the disclosure of which is hereby incorporated by reference in its entirety. BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a safety device for mounting onto an injection device such as a prefilled or pre-fillable syringe in order to protect a user from needle stick injuries after injection of a medical product. The invention also relates to an injection device including this safety device. Description of Related In this application, the distal end of a component or of a device is to be understood as meaning the end furthest from the user's hand and the proximal end is to be understood as meaning the end closest to the user's hand. Likewise, in this application, the “distal direction” is to be understood as meaning the direction of injection, with respect to the safety device or injection device of the invention, and the “proximal direction” is to be understood as meaning the opposite direction to said direction of injection, that is to say the direction towards the user's hand. Injection devices, such as pre-fillable or prefilled syringes, usually comprise a hollow body or barrel forming a container for a medical product. This body comprises a distal end in the form of a longitudinal tip defining an axial passageway through which the medical product is expelled from the container. The distal end is equipped with a needle for injection of the medical product into an injection site. In order to minimize the risks of needle stick injuries, injection devices may be equipped with a safety device that protects the needle after injection. Safety devices usually comprise a tubular body for receiving the syringe barrel, and a needle cover, in the form of a protective sleeve, that slides relative to the body. The needle cover has a retracted position in which the needle cover is substantially contained inside the body to allow a user to perform an injection, and an extended position in which the needle cover moves distally from the retracted position to cover the needle once the injection is completed. There are mainly two types of safety devices: passive or active. Passive safety devices do not require the user to perform any action to ensure that the needle cover moves in the extended position and covers the needle. Thus, these passive safety devices automatically shield the needle after injection. In contrast, the active safety devices need to be activated by the user, i.e. they require the user to undertake a specific action to trigger movement of the needle cover and thus protect the needle once the injection is completed. In active safety devices, movement of the protective sleeve from the retracted to the extended position is traditionally caused by the user exerting a distal activation force on a plunger rod of the injection device. This activation force needs to be high enough to prevent inadvertent triggering of the safety mechanism, but low enough to permit the users to easily activate the protective sleeve once the injection is completed. Therefore, there is a need to decrease the activation force to a required minimum and to reduce the variability of this activation force. SUMMARY OF THE INVENTION An aspect of the invention is a safety device for mounting onto a medical container provided with a flange and an injection needle, the safety device including: a tubular body extending along a longitudinal axis A, the tubular body being configured to receive the medical container,a needle cover movable relative to said body between a retracted position, and an extended position in which the needle cover distally extends from the retracted position in order to shield the injection needle after activation of the safety device,a release element configured to move the needle cover from the retracted to the extended position after activation of the safety device,a retainer, the retainer being configured to transmit a user's activation force to the needle cover once the injection operation is completed, whereinthe needle cover includes a distal abutment surface, said distal abutment surface abutting against a proximal abutment surface of a bump protruding from the body in the retracted position of the needle cover, wherein the body has a first axial slot extending from a distal end of the body, and the bump is circumferentially distant from said first axial slot. The safety device of the invention allows reducing the variability of this activation force. Indeed, the bump is closer to a flexion point, thereby reducing a lever arm between this flexion point and a second end of the bump. This decrease of the lever arm enables to decrease the variability of the activation force. The activation force may be a distal axial force. The retainer is thus configured to push the needle cover in the distal direction. The transmittal of the actuation force