| 摘要 |
<p>960,646. Feeding webs. SPERRY RAND CORPORATION. Aug. 15, 1961 [Aug. 15, 1960], No. 29459/61. Heading B6B. A web feeding device comprises a perforated roller 1 frictionally engaging a web 30 and a differential fluid valve 13 having an input connected to a source of fluid control signals and two outputs 11, 21, one of which 11 is connected to the roller 1 to create therein a pressure dependent upon the pressure of the fluid signals, whereby the acceleration and the speed of the web may be controlled. The valve 13, Fig. 4, is connected by conduits 15 and 17 to sources of fluid pressure signals so as to deflect the fluid stream from orifice 39 at the end of a conduit 19 to duct 29 or 27 according to whether the signal is applied to conduit 15 or 17, thus causing an increase in pressure in one duct and a reduction in the other. The outputs 11 and 21 may be connected to two rollers 1, 1a, Fig. 3, rotating in opposite directions, such that web 30 may be moved in opposite directions by applying signals to either conduit 15 or 17.</p> |
