The invention relates to a drive mechanism (9) for a needle insertion arrangement (1), the drive mechanism (9) being arranged as a bistable mechanism with at least one pivoted link (10, 11) having two stable end positions (LEP, UEP) and an instable transitional central position (CP), the drive mechanism (9) further comprising a spring (12) biasing the link (10, 11) out of the transitional central position (CP), wherein at least one trigger unit (17, 21) is arranged for moving the link (10, 11) out of at least one of the stable end positions (LEP, UEP) towards and beyond the transitional central position (CP) against the bias of the spring (12).
