1. An improved safe and convenient disposable automatic lancet comprising a body (1), a needle core (2) and a spring (3), characterized in that: the needle core (2) is provided with a needle body (14) with a needle tip (7)； the housing (1) forms an ejection chamber (5) in which the needle core (2) is located, while the needle core (2) has one end provided with a protective rod (4) and the other end fixed by a spring (3), and the protective the rod (4) has one end emanating from the needle ejection hole (6), and the other end is removably connected yenny with a needle core (2)； while the housing has an elastic lever (8) going inside the chamber (5) ejection, to block the needle core (2) on the needle core (2) is provided bayonet clip (9) corresponding to the end of the elastic lever (8), and the end of the elastic arm (8) is fixed with a bayonet clip (9), while the housing (1) is equipped with a start button (10) with a first push tab (11) and a second push tab (19), both of which are placed in expulsion chamber (5), while in a ready state, the distance between the second pressure th projection (19) and the tip (7) of the needle is less than the distance between the first pressing protrusion (11) and the tip (7) of the needle； the first pressing protrusion (11) is close to or in contact with the end of the elastic arm (8)； and the second pressing protrusion (19) is provided with a tooth (12), respectively, to which a self-locking hook (13) is provided on the housing (1)； moreover, the self-locking hook (13) is located on the pressure path of the tooth (12), when the second pressing protrusion (19) together with the tooth (12) provided on it is pressed down, while the tooth (12) and the self-locking hook (13) are1.Улучшенный безопасный и удобный одноразовый автоматический ланцет, содержащий корпус (1), игольный сердечник (2) и пружину (3), отличающийся тем, что:игольный сердечник (2) снабжен телом (14) иглы с наконечником (7) иглы；корпус (1) образует камеру (5) выталк
