Magnetic recording apparatus for positioning magnetic head to track on magnetic tape

Claim 1

A magnetic recording apparatus for positioning a magnetic head to track on a magnetic tape comprising: a tape drive means for causing a wide endless magnetic tape to revolve in a direction substantially along a longitudinal axis of a magnetic tape; a carrier retaining a magnetic head in confronted relation with a magnetic tape for movement in a direction substantially orthogonal to the longitudinal axis of a magnetic tape; a carrier motor drivingly connected to said carrier by a power transmission mechanism for converting a rotating motion of said carrier motor into a linear motion to be transmitted to said carrier, said power transmission mechanism including a screw rotated by said carrier motor and in threaded engagement with the carrier; a home position mark having a length substantially equal to the sum of a length of a magnetic tape transported during a period from a start of said tape drive means to stabilization of its rotating speed plus a length of a magnetic tape transported during a period from a shut off of said tape drive means to its stopping, said home position mark being formed on said magnetic tape; a detector means for optically detecting said home position mark thereby setting a stopping period of said tape drive means; and discrete drive means for discretely driving said carrier motor at intervals of a predetermined period during one revolution of the magnetic tape except for a period during which said home position mark is detected to cause the magnetic head of said carrier to track along a magnetic tape in a single continous, substantially spiral track.