Improvements in or relating to pneumatic apparatus for transporting web

930,665. Feeding webs. ELECTRIC & MUSICAL INDUSTRIES Ltd. Nov. 26, 1959 [Nov. 26, 1958], No. 38034/58. Class 100 (1). [Also in Group XXXVIII] An apparatus for feeding a web, especially magnetic tape, in either of two directions comprises a pair of vacuum capstan rollers 6, 8, means for continuously rotating the capstan rollers in opposite directions, means for selectively applying high suction to the rollers so as to feed the web in a direction dependent on the roller to which high suction is applied, and means for releasing the high suction from the roller effecting feed and for momentarily applying high suction to the other roller so that a braking force is applied to the travelling web. As shown, tape 2 is fed into a bin 5 by a vacuum capstan roller 4. Capstan rollers 6, 8 rotate in opposite directions to feed the tape 2 in either direction across a perforated surface 7 connected to suction past a transducer or transducers (not shown). The rollers 6 and 8 each have a high suction chamber 15 and a low suction chamber 16 connected by a valve 17 operable to couple the chamber to high or low suction or in an intermediate position to connect the chambers 15 and 16. The tape is fed in the direction of rotation of the roller connected to high suction. When it is required to arrest the tape, valve 17 of the roller 6 or 8 feeding the tape is actuated so that high suction to that roller is terminated. The low suction chamber 16 of that roller is momentarily connected to the high suction chamber 15 during the operation of the valve 17, thus creating a decrease in pressure in a conduit 20 connected to the chamber 16 of the other vacuum capstan roller 6 or 8 to cause braking of the tape. The tape may be guided into the bins 5 and 9 by stepped plates and the tape caused to form ripples by air blasts directed inwardly of the bins, thereby preventing long loops being formed in the middle of the bin. Specifications 918,691 and 930,664 are referred to.