Abstract: A switch assembly comprising a chassis supporting a PCBA which has a distal surface comprising at least a first, a second, and a third electrical contacts, a ring having a ratchet profile, and a first arm and a second arm. The chassis moves axially relative to the ring during a first switch operation mode. The ring rotates relative to the chassis during a second switch operation mode. An axial movement of the chassis towards the ring closes an electrical connection between the first electrical contact and the first arm. Further, the ratchet profile of the ring is located facing proximally towards the distal surface of the PCBA such that an actuator guided on the ratchet profile elastically deforms the second arm thereby alternately opening and closing an electrical connection between the second electrical contact and the third electrical contact via the second arm.

Abstract: The invention relates to a method for assembling a cassette for use in an auto injector.

Abstract: The present disclosure refers to a switch assembly for an electronic system of a drug delivery device. The switch assembly comprises a chassis supporting a PCBA which has a distal surface comprising at least a first electrical contact, a second electrical contact and a third electrical contact, and a ring. The chassis moves axially relative to the ring from a first axial position to a second axial position during a first switch operation mode. The chassis and the ring are configured such that the ring rotates relative to the chassis during a second switch operation mode. The ring comprises an annular continuous first electrically conductive area and an annular segmented second electrically conductive area which is connected to the first area.

Abstract: The invention also relates to an improved auto injector adapted for receiving a cassette with medicament and for administering the medicament in the cassette to a patient, the auto injector extending from a proximal end to a distal end along a longitudinal axis, wherein the cassette is removable received in the auto injector along the longitudinal direction.