Twist preventing mechanism for leaf hinge spring in a magnetic head assembly

Claim 1

In a magnetic head assembly including a carriage base and an arm supported for pivoting movement toward and away from the carriage base by a leaf hinge spring mounted between a mounting portion of the carriage base and one end of the arm, the improvement comprising: said mounting portion of said carriage base having a pair of base end portions spaced apart in a widthwise direction along a pivot axis of said arm with said leaf hinge spring disposed therebetween; said one end of said arm having a pair of supporting sections which are correspondingly spaced apart in the widthwise direction along the pivot axis of said arm, wherein said supporting sections have respective lower face portions which abut against said base end portions of said carriage base when said arm is lifted in a pivoting movement away from said carriage base; and a pair of cap plates mounted to said mounting portion which are spaced apart in the widthwise direction along the pivot axis of said arm and are positioned closely adjacent respective upper face portions of said supporting sections and separated therefrom with only a slight gap therebetween, whereby said pair of cap plates operate, by abutment of said upper face portion of each said supporting section with a corresponding one of said cap plate when said slight gap is closed, so as to restrict any substantial lifting movement of either of said supporting sections when said arm is pivoted away from said carriage base in order to minimize any twisting of the leaf hinge spring.