A THERMAL PRINTHEAD DETECTING DEVICE AND METHOD AND A THERMAL PRINTER USING THE SAME

摘要

A thermal print head detecting device comprises a power supply (1), a power supply switch (4), a power supply switch control circuit (5), a first detecting resistor (Ra), a second detecting resistor (Rb), a print head (2) to be detected and a print head control circuit (3); an output end of the power supply (1) is connected to a common joint (N) of respective heating elements of the print head through the power supply switch (4), the first detecting resistor (Ra) is connected in parallel with the power supply switch (4); an output end of the power supply switch control circuit (5) is connected to a control end of the power supply switch (4); the second detecting resistor (Rb) has one end connected to the common joint (N) of the heating element units, and the other end grounded; and the print head control circuit (3) controls strobing of each heating element unit of the print head. The thermal print head detecting device does not need an exclusive power supply, which prominently simplifies the circuit of the detecting device and decreases the cost.