Label printer and label printing method for precise positioning thereof

A label printer, comprising:

• an outer shell,
• a label cartridge arranged inside the outer shell,
• a power mechanism,
• a control mechanism, and
• a print head configured to realize label printing,
• wherein the power mechanism and the control mechanism are configured to control paper output of the label cartridge and winding and unwinding of a carbon ribbon;
• wherein the label cartridge comprises an inner shell, a label paper output channel and a carbon ribbon channel, wherein the label paper output channel and the carbon ribbon channel are arranged inside the inner shell;
• an interior of the inner shell is divided into a first half area and a second half area;
• a label paper roll is provided at a lower part of the first half area, and a label rollback release space is reserved at an upper part of the first half area;
• a carbon ribbon supply roll and a carbon ribbon take-up roll are provided at a lower part of the second half area, and a groove configured to place the print head is provided at an upper part of the second half area, a center of the groove being arranged in a portion of the label cartridge above the carbon ribbon supply roll and the carbon ribbon take-up roll;
• the label paper output channel is arranged along an uppermost end of the second half area, and the label paper output channel is in linear correspondence with a paper output port on a side wall of the inner shell and a side wall of the outer shell;
• the carbon ribbon channel is arranged around the groove, and the carbon ribbon at an open end of the groove is tightly attached to a label paper;
• the power mechanism comprises an electric motor and a gear transmission system;
• the gear transmission system comprises:
• a first gear set in transmission connection with an output shaft of the electric motor,
• a planetary gear set in transmission connection with the first gear set,
• a printing rubber roll gear set being in transmission connection with the planetary gear set and configured to drive the label paper to move forward or reversely,
• a carbon ribbon winding gear, and
• a carbon ribbon unwinding gear,
• wherein the carbon ribbon winding gear and the carbon ribbon unwinding gear are selectively in transmission connection with the planetary gear set;
• the planetary gear set comprises a sun gear, a planetary gear meshed with the sun gear, and a planetary carrier connecting the sun gear and the planetary gear;
• the sun gear is driven by the first gear set to drive the planetary gear to rotate, and under an action of the planetary carrier, the planetary gear is meshed with the carbon ribbon winding gear or the carbon ribbon unwinding gear based on forward rotation or reverse rotation of the sun gear;
• and
• the printing rubber roll gear set in the gear transmission system is connected to a printing rubber roll;
• the printing rubber roll drives, through friction with the label paper, the label paper to move;
• the carbon ribbon winding gear is connected to the carbon ribbon take-up roll, and the carbon ribbon unwinding gear is connected to the carbon ribbon supply roll;
• when the electric motor rotates to one side, the first gear set transmits power to the planetary gear set, and the planetary gear set drives the printing rubber roll and the carbon ribbon take-up roll to rotate to realize output of the label paper and take-up of the carbon ribbon;
• when the electric motor rotates to an opposite side, the first gear set transmits reverse power to the planetary gear set, and the planetary gear set drives the printing rubber roll and the carbon ribbon supply roll to rotate to realize rollback of the label paper and recovery of the carbon ribbon,
• wherein the label cartridge is configured to use a continuous label paper roll and a die-cut label paper roll, and
• wherein when the label cartridge contains a continuous label paper roll the label paper follows a first path, and when the label cartridge contains a die-cut label paper roll the label paper follows a second path.