US-20260124395-A1 - MEDICAMENT DELIVERY DEVICE WITH TRANSPORT LOCK

US20260124395A1US 20260124395 A1US20260124395 A1US 20260124395A1US-20260124395-A1

Abstract

The present disclosure provides a power pack for a medicament delivery device. The power pack includes a tubular body including a protrusion having a second contact surface, and including a release button having a flexible arm having a first contact surface. The first and second contact surfaces are angled with respect to a lateral axis of the tubular body, such that if the release button is pressed towards a proximal end of the tubular body before the power pack is assembled with a front assembly, the contact surfaces abut and cause a blocking of the release button from moving further towards the proximal end. The blocking includes a pressing of the flexible arm radially outwards towards an inside wall of the tubular body. A corresponding release button, a tubular body and a medicament delivery device are also provided.

Inventors

Daniel Carlsson

Assignees

SHL MEDICAL AG

Dates

Publication Date: 20260507
Application Date: 20221012
Priority Date: 20211026

Claims (12)

1 - 11 . (canceled)
12 . A power pack for a medicament delivery device, comprising: a tubular body extending along a longitudinal axis from a proximal end to a distal end, wherein the tubular body comprises a protrusion which extends radially inwards from a section of an inside wall of the tubular body and includes a second contact surface; and a release button at least partially arranged within the tubular body and movable in relation to the tubular body along the longitudinal axis, wherein the release button comprises a flexible arm extending towards the proximal end and wherein an end of the flexible arm includes a first contact surface, wherein the first contact surface and the second contact surface are both angled with respect to a lateral axis of the tubular body, such that if the release button is pressed towards the proximal end before the power pack is assembled with a front assembly of the medicament delivery device, the first contact surface and second contact surface abut and cause a blocking of the release button from moving further towards the proximal end, the blocking including a pressing of the end of the flexible arm radially outwards towards the section of the inside wall of the tubular body, and wherein during assembly of the power pack with the front assembly, a surface of a distally extending prying arm of a housing comprised in the front assembly abuts and slides along an outer surface of the flexible arm causing the flexible arm to bend radially inwards such that said blocking of the release button from moving further towards the proximal end is prevented.
13 . The power pack according to claim 12 , wherein: the first contact surface and the second contact surface are angled with respect to the lateral axis of the tubular body such that the first contact surface faces away from the section of the inside wall of the tubular body and radially inwards towards the longitudinal axis, and such that the second contact surface faces towards the section of the inside wall of the tubular body and radially outwards away from the longitudinal axis.
14 . The power pack according to claim 13 , wherein: the end of the flexible arm includes an additional angled surface forming part of the outer surface of the flexible arm, the additional angled surface being angled with respect to the lateral axis of the tubular body such that the additional angled surface faces towards the section of the inside wall of the tubular body and radially outwards away from the longitudinal axis, and such that, during the assembly of the power pack with the front assembly, the surface of the prying arm abuts and slides along the additional angled surface to cause at least part of the bending of the flexible arm radially inwards.
15 . The power pack according to claim 12 , wherein: the release button has a tubular body extending along the longitudinal axis, and the flexible arm is formed as part of an outer shell of the tubular body of the release button
16 . The power pack according to claim 12 , wherein: the tubular body of the power pack includes an inner tubular section arranged fixed relative to the tubular body and extending along the longitudinal axis, and wherein the power pack further comprises: a power spring and a plunger rod coaxially arranged at least partly within the inner tubular section, wherein the power spring is compressed and abuts a proximal rim of the plunger rod such that, when the power spring is released by said moving further of the release button towards the proximal end, the power spring drives the plunger rod along the longitudinal axis towards the proximal end.
17 . The power pack according to claim 16 , wherein: the inner tubular section includes a distal flexible arm configured to abut a distal rim of the plunger rod to block the power spring from being released and the plunger rod from moving along the longitudinal axis towards the proximal end, and the release button includes a protrusion extending from a distal end of the release button towards the proximal end of the tubular body, and configured to, as a result of said moving further of the release button towards the proximal end, abut a distal surface of the flexible arm of the inner tubular section and cause a bending of the flexible arm radially outwards, and thereby prevent the blocking of the power spring from being released and the plunger rod from moving along the longitudinal axis towards the proximal end.
18 . A release button for a power pack for a medicament delivery device, extending along a longitudinal axis from a proximal end to a distal end, and configured to be moveably arranged at least partially within inner tubular body of the power pack, the release button comprising: a flexible arm extending towards the proximal end, and wherein an end of the flexible arm includes a first contact surface, the first contact surface being configured to mechanically interact with a corresponding second contact surface of a protrusion of the tubular body to block a movement of the release button towards a proximal end of the tubular body, wherein the first contact surface is angled with respect to a lateral axis of the release button, such that said first contact surface faces radially inwards towards the longitudinal axis.
19 . The release button according to claim 18 , wherein: the end of the flexible arm includes an additional angled surface forming part of an outer surface of the flexible arm, the additional angled surface being angled with respect to a lateral axis of the release button such that the additional angled surface faces radially outwards away from the longitudinal axis.
20 . The release button according to claim 18 , wherein: the release button has a tubular body extending along the longitudinal axis, and the flexible arm is formed as part of an outer shell of the tubular body.
21 . A tubular body for a power pack for a medicament delivery device, extending along a longitudinal axis from a proximal end to a distal end, and configured to receive a release button of the power pack such that the release button is movable along the longitudinal axis, the tubular body comprising: a protrusion which extends radially inwards from a section of an inside wall of the tubular body and includes a second contact surface, the second contact surface being configured to mechanically interact with a corresponding first contact surface of a flexible arm of the release button to block a movement of the release button towards the proximal end along the longitudinal axis, wherein the second contact surface is angled with respect to a lateral axis of the tubular body, such that said second contact surface faces radially outwards away from the longitudinal axis.
22 . A medicament delivery device, comprising: a power pack according to any one of claim 12 .

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application is a U.S. National Phase Application pursuant to 35 U.S.C. §371 of International Application No. PCT/EP2022/078340 filed Oct. 12, 2022, which claims priority to European Patent Application No. 21204816.9 filed Oct. 26, 2021. The entire disclosure contents of these applications are herewith incorporated by reference into the present application. TECHNICAL FIELD The present disclosure relates to the field of medicament delivery devices. In particular, the present disclosure relates to a power pack for such a device having a transport lock. BACKGROUND Autoinjectors and other types of medicament delivery devices are designed to allow for a user (e.g. a patient) to perform self-administration of a dose of a particular medicament in a controlled way. After positioning the device at the site of the body where the injection is desired, the user activates the device by pushing a release button. Pushing the release button releases a pre-compressed power spring which, when released, in turn drives a plunger rod towards the proximal end of the autoinjector. The plunger rod comes into contact with a syringe in which the medicament to be delivered is stored, and the movement of the plunger rod forces the medicament out of the syringe and into the injection site. In some autoinjectors, the movement of the plunger rod is also responsible for first inserting the needle into the bodily tissue at the injection site. Autoinjectors can be manufactured and delivered from the factory in multiple parts, or sub-assemblies, where the parts can then be finally assembled at a later stage as needed. For example, the release button, pre-compressed power spring and plunger rod may be delivered as part of a so-called power pack, while the needle and syringe may be delivered as part of a so-called front assembly. In this way, a same power pack may e.g. be combined with front assemblies having different types of syringes and/or containing different kinds of medicaments. In order to prevent a user from activating the power pack before it has been assembled with the front assembly, the power pack can include some form of transport lock. One available solution includes the release button having a flexible arm which extends towards the proximal end of the power pack, and which, if the release button is pressed, abuts e.g. a protrusion located on a wall of a body of the power pack in which the release button is arranged. This may prevent the release button from being sufficiently pressed to activate the power pack, as the abutting of the flexible arm and the protrusion restricts the possible length of travel for the release button. At the same time, the front assembly may be provided with a corresponding prying arm which extends in a distal direction, and such that when the front assembly and the power pack are assembled, the prying arm comes into contact with the flexible arm of the power pack and bends the flexible arm radially inwards such that it no longer abuts the protrusion, and such that the release button can then be pushed fully to activate the power pack and the autoinjector. However, if excessive force is applied on the release button before the power pack has been assembled with the front assembly, such a solution may not be sufficient to keep the release button from being accidentally pushed, resulting in an undesired premature activation of the power pack which can be both inconvenient and even dangerous to the user of the device. SUMMARY To at least partially solve the above identified problem with accidental and undesired activation of the power pack before final assembly of the medicament delivery device, the present disclosure provides an improved power pack, an improved release button, an improved body for the power pack, and an improved medicament delivery device, as defined in the accompanying independent claims. Various alternative embodiments are defined in the dependent claims. According to a first aspect of the present disclosure, a power pack for a medicament delivery device is provided. The power pack includes a tubular body extending along a longitudinal axis from a proximal end to a distal end. The tubular body includes a protrusion which extends radially inwards from a section of an inside wall of the tubular body. The protrusion includes a second contact surface. The power pack further includes a release button at least partially arranged within the tubular body and movable in relation to the tubular body along the longitudinal axis. The release button includes a flexible arm extending towards the proximal end. An end of the flexible arm includes a first contact surface. The first contact surface and the second contact surface are both angled with respect to a lateral axis of the tubular body, such that if the release button is pressed towards the proximal end before the power pack is assembled with a front assembly of the medicament delivery device,