| 摘要 |
PURPOSE:To shorten the period of time required to form a table, by fixingly providing a value of an applied voltage at which a change in resistance appears, in determining a voltage of a voltage pulse to be applied by using a resistance vs. applied voltage table. CONSTITUTION:The resistance change ratio of a resistor capable of being approximated by the equation based on measurements for selected samples of dots in a thermal head varies substantially along a fixed curve, irrespective of the initial resistance of the resistor. In the equation, R0 is the initial resistance of a heat generating resistor, V0 is a boundary value of applied voltage at which a change in resistance appears, DELTAV is the change in resistance, and alphaand beta are constants. The boundary values V0 of applied voltage are centralized at about 25V. The resistance change ratio DELTAR=(R-R0)/R0 is put into the equation, with the boundary voltage V0 given as a fixed value of 25V, whereby a solution can be speedily obtained. Specific values DELTARn of the resistance change ratio are sequentially put into the equation to calculate the values of the applied voltage at a given moment, thereby forming a resistance vs. applied voltage table. A voltage Vn to be applied is determined based on the table. |
