Medicament delivery device

A medicament delivery device comprising:

• a housing comprising a proximal end and a distal end;
• a needle and a needle cover,
• wherein the needle cover is axially movable between an extended position, in which the needle cover extends from the distal end of the housing and covers a distal end of the needle, and a retracted position, in which the needle cover is located in a proximal position relative to the extended position such that the needle protrudes from a distal end of the needle cover;
• a needle cover biasing member configured to bias the needle cover axially in a distal direction towards the extended position;
• a skin sensor extending distally from the distal end of the needle cover and configured to contact an injection site;
• a skin sensor biasing member acting between the needle cover and the skin sensor, the skin sensor biasing member being configured to bias the skin sensor axially in the distal direction from a proximal position to a distal position away from the needle cover;
• and
• a retaining mechanism configured to temporarily retain the needle cover in the retracted position and temporarily transfer at least a part of a force of the needle cover biasing member to the housing such that the needle cover biasing member is prevented from moving the needle cover distally, wherein the retaining mechanism comprises a proximally extending arm of the needle cover, a catch located on an inner surface of the housing, and a proximally extending reinforcing member of the skin sensor, wherein a projection on a proximal end of the arm is configured to engage the catch when the needle cover is in the retracted position, wherein the reinforcing member is configured to prevent the projection from disengaging from the catch when the needle cover is held in the retracted position and the skin sensor is held in the proximal position, and
• wherein upon depression of the medicament delivery device against the injection site, the skin sensor is configured to be moved from the distal position to the proximal position before the needle cover is moved from the extended position to the retracted position.