In high speed magnetic tape handlers, magnetic tape is reeled back and forth between a supply reel and a take-up reel passing over a record/play-back head. The tape is drawn across the head by a capstan usually driven by a fast response low inertia DC motor. In such machines the tape is accelerated and decelerated at extremely high rates posing a very severe problem on means for maintaining uniform tension on the tape in the vicinity of the record/play-back head at all times. The inertia of the supply and take-up reels is such that, although they may be driven by powerful servo motors, they cannot provide the required uniform tension. Accordingly, it is usual to provide a substantial vacuum buffer on each side of the capstan and between it and the servo controlled reels. These vacuum buffers are typically provided by means of rectangular straight channels generally about 2 to 3 inches wide and as long as dictated by the response time of the reel servos. Vacuum ports at appropriate points, particularly at the bottom of the tank, couple a vacuum system to the buffer channels. Additional small buffers may be provided usually one on each side of the record/play-back head, to accommodate rapid acceleration of the tape.
A typical high speed magnetic tape handler is constructed with the two reels (supply and take-up) mounted in the upper part of a cabinet enclosure with the capstan and head mounted below and the two vacuum tanks extending downward, centrally located and side-by-side. Illustrating the system with 101/2 inch diameter reels, a typical cabinet is of the order of 27 inches wide and 63 inches high. The result is a substantial area of unused space on each side of the vacuum tanks and below the reels. It is the object of the present invention to more efficiently use the cabinet area.