This invention relates to disk drives for storing information, and more particularly, to an actuator arm assembly for a disk drive.
Disk drives have an actuator arm which moves magnetic read/write heads into engagement with a recording media, either a flexible disk or a rigid disk in a removable cartridge.
Most disk drives contain an actuator bearing assembly around which an arm, holding the read/write transducer, pivots. Forces (and therefore torques) are imparted to the actuator arm by means of an actuator, usually a voice coil motor, or such. These forces, besides providing the torques required to actuate the arm, tend to deflect the actuator arm and bearing assembly, and therefore, the read/write transducers, in an undesirable direction, the "in-plane" direction. In order to reduce such deflections, many disk drives have the top of the bearing assembly secured to a rigid structural member, such as a stiff top cover or the steel part of the magnet assembly. The bottom is usually attached to a base casting, or plate. This anchors both the top and bottom of the bearing assembly and allows for a much stiffer bearing assembly.
However, as the bearing assembly is being attached to that rigid structural member, the bearing assembly can be significantly tilted so as to introduce unwanted distortion. This can be especially a problem if the stiffness or parallelism of the base casting (or plate) is poor (or competes) with the stiffness and parallelism of the other rigid structural members.
It is an object of the present invention to reduce the deflection of the actuator arm due to the forces applying torque to the arm, while avoiding the unwanted distortion introduced by prior art techniques of securing the bearing assembly to a structural member.
Disk drive actuators usually have a fork-like structure at one end to attach a coil such as that of a rotary voice coil motor. Such a fork can make it difficult to locate the coil, especially in the vertical direction, while trying to attach the coil, as with an adhesive or other potting method.
It is another object of the present invention to provide an improved technique of locating the coil on the actuator arm.