Thermal compensation mechanism for magnetic disk drive data storage units

Claim 1

In a rotating disk media type magnetic data storage device having within enclosure at least one magnetic disk mounted for rotation on a deck, and a unitary arm assembly for supporting a plurality of transducers adjacent to the disk surfaces and for moving each transducer radially with respect to a disk, said arm assembly mounted for rotation on the deck, and having at least first and second bilaterally asymmetric arms projecting from the arm assembly's axis of rotation and each arm aligned adjacent to the surface of a disk and each carrying at its free end at least one transducer, and said arm assembly further formed of a material having a first temperature coefficient, and an actuator for rotating the arm assembly to position the transducers radially on the disk surfaces, said enclosure having heat sources changing the interior temperature with time, said heat sources affecting the temperature of one of said arms more than another, and said arm assembly experiencing changes in the relative angular position of a first arm of the arm assembly with respect to a second arm as a function of the relative changes in temperature, misalignment of the individual transducer carried by said first and second arms resulting misalignment of the first and second arms, comprising in the first arm an area along an edge thereof having a slot extending transversely with respect to the length of the arm, and within the slot, a body with an interference fit in the walls of the slot, said body having a second temperature coefficient different from the first temperature coefficient, whereby the different temperature coefficients of the body and the arm cause temperature-induced distortion of the first arm in which the body is placed which compensates at least in part the misalignment in the arm assembly.