Patent ID: 7981131

Claim:
A disposable single-swing-arm incision safety lancet, comprising: a casing ( 2 ) and a trigger; wherein: the casing ( 2 ) is provided inside with an incision blood-taking mechanism composed of a cam ( 3 ), a swing arm ( 4 ), a blade ( 1 ) and a spring ( 8 ); the cam ( 3 ) is rotatably fixed in the casing ( 2 ) via a pivot ( 6 ); the spring ( 8 ), as a driving element of the incision blood-taking mechanism, is positioned between the cam ( 3 ) and the casing ( 2 ), and acts on the rotary direction of the cam ( 3 ); the trigger, as a triggering control member of the incision blood-taking mechanism, is positioned on the casing ( 2 ); in a pre-triggering state, an action portion ( 10 ) of the trigger is propped against a lock gate ( 7 ) provided on the cam ( 3 ), and forces the spring ( 8 ) to be in an energy storage state, with a triggering portion ( 11 ) of the trigger being stretched out of the casing ( 2 ); the swing arm ( 4 ) is provided with a locating end ( 12 ) and a swing end ( 13 ), the locating end ( 12 ) being positioned in the casing ( 2 ), the swing end ( 13 ) being hung in the casing ( 2 ); the blade ( 1 ) is fixedly mounted on the swing end ( 13 ), which is further provided with a working face ( 14 ), which is contactively matched with flange of the cam ( 3 ); the flange of the cam ( 3 ) is provided, corresponding to this working face ( 14 ), with a curved surface ( 15 ), whose curvature radius is transient from a first radius (R 1 ) to a second radius (R 2 ); this curved surface ( 15 ) forces the swing arm ( 4 ) to swing with rotation of the cam ( 3 ), with the distance from center of the locating end ( 12 ) itself to the point of the blade ( 1 ) as a third radius (R 3 ); the blade ( 1 ) is located at a blood-taking opening ( 5 ) provided on the casing ( 2 ); when the incision blood-taking mechanism swings, the point of the blade ( 1 ) is swingingly stretched out of the casing ( 2 ) from the blood-taking opening ( 5 ) along an arc-shaped path (A); when the curved surface ( 15 ) on the cam ( 3 ) is rotated past the working face ( 14 ) on the swing arm ( 4 ), the swing arm ( 4 ), by means of the self flexibility, makes the point of the blade ( 1 ) swing back to inside the casing ( 2 ) along the arc-shaped path (A).