PURPOSE: To stabilize the travelling of a tape and to improve the wear resistance of both a cylinder and the tape by floating the tape on the cylinder by the generation of dymanic pressure of spiral grooves set up to the optimum status.
CONSTITUTION: A pump-out type grooves 6 are provided to the surface perpendicular to a rotary shaft 3a opposed to rotary and fixed cylinders 2, 3 to obtain pressure necessary for floating the tape 1 by a fixed level against tape tension loaded to the tape 1. For instance, spiral grooves of which black parts 7 are grooves and white parts 8 are lands are formed on a rotating member 2, the groove angle β is set up to the range of 2°≤β≤45° and the groove width ratio γ obtained by dividing one spiral groove setting width by the sum value of the width of a pair of spiral groove setting part and unsetting part, and defining the divided value non-dimensionally is set up to the range of 0.2≤γ≤0.8 to float the tape around the rotary head assembly.
ICHIYANAGI TAKASHI
IMANISHI KIYOKAZU
SAKURAI YASUO
KISHIMOTO KATSU
