Skin treatment device for drug injection, and operation method for skin treatment device

A medical skin treatment device comprising:

• a main body including a control unit configured to control an operation of the skin treatment device and a power source unit configured to supply power to the medical skin treatment device;
• a transfer unit configured to move the main body;
• and
• a handpiece that receives power from the power source unit of the main body, is controlled by the control unit, and injects a drug into a patient's skin to improve the skin,
• wherein the handpiece includes:
• a base unit formed on one side of the handpiece;
• and
• a drug injection unit that is formed on one side of the base unit and injects the drug into the patient's skin, and
• the drug injection unit includes:
• a drug cylinder including a first chamber that receives and stores the drug from a drug supply unit and a second chamber that accommodates an expansion fluid for discharging the drug in the first chamber;
• a separator formed between the first chamber and the second chamber to prevent the fluid from flowing between the first chamber and the second chamber and formed of an elastic material;
• an injection valve formed in the second chamber to inject the expansion fluid of a predetermined mass into the second chamber;
• an ignition plug that is formed in the second chamber and expands the expansion fluid injected into the second chamber;
• and
• a discharge valve that is formed in the second chamber and discharges the expansion fluid expanded by the ignition plug from the second chamber.