| 摘要 |
PURPOSE:To make an off-track amount zero without fail by selecting properly a joint position of a carriage and belt, both of which are different in coefficients of thermal expansion, and changing an off-track amount at an average track position. CONSTITUTION:Coefficients of thermal expansion alpha3 and alpha4 of a belt 9 and head carriage 10 are set to different values, and moreover a joint position B between the belt 9 and carriage 10 is set so that an off-track amount DELTAL per 1 deg.C of a temperature change at the average track position on a magnetic recording medium 2, which is defined by the expression, can be within a range of + or -30X 10<-6>mm.. In the expression, the following notations are applicable: l1: inter-shaft distance between a disk drive motor 3 and stepping motor 6; l2: average intertrack distance between a motor drive shaft 4 and magnetic recording medium 2; l3: inter-joint B distance between a rotating shaft 5 of the stepping motor and the carriage 10; l4: distance between the joint B and a magnetic head 10 of a tip of the carriage 10; alpha1: chassis 1; alpha2: magnetic recording medium; alpha3: belt 9; alpha4: head carriage 10; alpha5: coefficient of thermo expansion of a pulley 7; r: radius of the pulley 7. |
