Medicament infusion device

An insertion assembly, comprising:

• a frame comprising a tubular sidewall defining an internal cavity, the frame having a first end portion configured to be positioned against the skin of a user and a second end portion opposite the first end portion along a longitudinal axis of the frame, wherein the frame includes a slot extending longitudinally along a portion of the sidewall;
• a needle;
• a needle carrier carrying the needle and at least partially disposed within the internal cavity of the frame, the needle carrier axially movable within the frame, wherein the needle carrier includes a needle carrier protrusion disposed within the slot of the frame and configured to slide within the slot when the needle carrier moves axially within the frame;
• a cannula;
• a cannula carrier carrying the cannula and at least partially disposed within the internal cavity of the frame, the cannula carrier axially movable within the frame, wherein the cannula carrier includes a cannula carrier protrusion disposed within the slot of the frame and configured to slide within the slot when the cannula carrier moves axially within the frame;
• wherein the cannula carrier protrusion and needle carrier protrusion together form a sliding interface, and wherein:
• the sliding interface is bound longitudinally between a top surface of the needle carrier protrusion and a bottom surface of the cannula carrier protrusion, and has a height measured between the top and bottom surfaces,
• the sliding interface is bound laterally between first and second side surfaces that abut the sidewall on either side of the slot, the sliding interface having a width measured between the first and second side surfaces, and
• a ratio of the height of the sliding interface to the width of the sliding interface is greater than 1.