Capstan drive system for driving tape record media, and having internally mounted transducer head means

A tape transducer system comprising a driving capstan having a rotatable tape engaging capstan surface for driving engagement with an inner surface of a tape record medium wrapped on the capstan to produce uniform movement of the record medium substantially at a speed corresponding to the speed of said capstan surface, and having a capstan annular slot in said surface, stationary transducer head means in said annular slot and having a stationary coupling means at the capstan surface and at a fixed scanning location for coupling with a tape record medium as it is being driven by the capstan surface so as to transduce information between a recorded form on the record medium and a signal form at said transducer head means, and said transducer head stationary coupling means at said fixed scanning location scanning the tape record medium along a longitudinal track of the record medium and at a relative scanning speed substantially corresponding to the speed of said capstan surface, said annular slot in said capstan surface being of configuration to accommodate the transducer head stationary coupling means therein at said fixed scanning location and in scanning engagement with an inner surface of a tape record medium wrapped partially about the capstan, and said annular slot providing clearance between the capstan and said transducer head coupling means so that the capstan can be rotated while the transducer head coupling means is stationary in said annular slot, stationary slot obstructing means angularly offset from said fixed scanning location and extending in obstructing relation to portions of said annular slot remote from said stationary coupling means and which portions are not covered by a tape record medium wrapped on the capstan during operation and defining with said capstan an interior chamber in communication with the inner side of a tape record medium wrapped on the capstan in the vicinity of said stationary transducer head coupling means, such that during operation a substantial differential pressure can be established between the inner and outer sides of a tape record medium wrapped on said capstan, and a vacuum pump for communication with the interior chamber of the capstan for establishing said substantial differential pressure between the inner and outer sides of a tape record medium partially wrapped about said capstan and covering a part of the circumferential extent of said annular slot and such differential pressure being of a substantial magnitude over at least about one-half of the perimeter of said annular slot such that the tape record medium is held in an essentially non-slipping engagement with said capstan surface at both sides of said annular slot over at least about one-half of the perimeter of said annular slot at the part of the angular extent of said annular slot remote from said stationary slot obstructing means.