Drug delivery device

A drug delivery device, the characterized in that, the drug delivery device comprising:

• a pen cap (1), a right side of the pen cap (1) is fixedly provided with a drug administration mechanism (101), a right end surface of the drug delivery mechanism (101) is fixedly provided with a metering adjustment mechanism (201), an inner wall of a right end surface of the pen cap (1) is provided with a ratchet socket (11), an inner wall of the ratchet socket (11) is provided with a driving ratchet (10);
• the drug administration mechanism (101) further includes a drug administration element and a connection element, one side of the drug administration element is connected to one side of the connection element;
• the connection element further includes a pen holder (14), a left side of the pen holder (14) and a right side of the pen cap (1) are connected through the ratchet socket (11), a driving rod (6) is provided inside the pen holder (14), a pushing rod (12) is provided inside the driving rod (6), one side of the pushing rod (12) is slidingly connected to an inner wall of the driving rod (6), and one side of the pushing rod (12) is connected to one side of the driving ratchet (10);
• the metering adjustment mechanism (201) further includes an adjustment element and an observation element, one side of the adjustment element is connected to one side of the observation element;
• and
• the adjustment element further includes a knob (16), and a left end surface of the knob (16) is connected to a right side of the pen holder (14).