Lancet

A lancet comprising:

• an inner sleeve;
• a needle core;
• a housing extending along a longitudinal axis from a first side to a second side, the housing comprising an inner sleeve guiding portion extending along the longitudinal axis from the first side towards the second side and configured to guide movement of the inner sleeve, and a first needle core guiding portion configured to guide movement of the needle core;
• the inner sleeve provided inside the housing and configured to move along the inner sleeve guiding portion, wherein the inner sleeve comprises an inner sleeve needle outlet provided on a front end of the inner sleeve, and a second needle core guiding portion;
• the needle core comprising a needle core body configured to move axially along the first needle core guiding portion, and a needle body;
• and
• a spring provided inside the housing to drive the needle core to move axially towards the inner sleeve needle outlet,
• wherein:
• the first needle core guiding portion is a first needle core guiding groove which extends axially along the housing;
• the second needle core guiding portion extends axially and is a second needle core guiding groove;
• the housing further comprises a rotation guiding groove which has a radial rotation angle and is disposed at a position closer to the second side of the housing than the inner sleeve guiding portion, and which is configured to guide a guiding protrusion at a rear end of the inner sleeve so as to guide the inner sleeve to rotate with the radial rotation angle at the rotation guiding groove;
• in the installed state, the front end of the inner sleeve is located outside the housing;
• the inner sleeve, when pressed from the front end of the inner sleeve towards the inside of the housing, is configured to be guided by the rotation guiding groove to rotate such that the first needle core guiding portion is aligned with the second needle core guiding portion in a radial direction.