Resources Contact Us Home
Web handling apparatus

Image Number 7 for United States Patent #3948425.

A web handling mechanism is described for incrementally feeding a web of stretchable material (e.g., plastic film) to a processing station. The web feed rollers are driven by a motor incorporated in a servo system which electronically controls the feed rate, length of increment, dwell at processing station, etc. Variations in the speed and elasticity of a moving web are accommodated by means of a vacuum box adapted to accumulate a loop of the web material in the box and maintain proper tension on the web as supplied to the feed rollers. A detector in the vacuum box responds to a predetermined length of web accumulated in the box to trip a control circuit which actuates the feed roller motor to move the desired length of web through the processing station and then stop for a preselected interval. The circuit also controls the processing station to synchronize its operation with that of the web feed and the entire sequence is repetitive at high speed. Complete flexibility of operation is provided by the control circuit.

  Recently Added Patents
Supporting multiple channels of a single interface
Fluid conduit with PTC fabric heating
Methods for the production of aligned carbon nanotubes and nanostructured material containing the same
Bicyclic azaheterocyclic carboxamides
Output device, source apparatus, television set, system, output method, program, and recording medium
Insulin derivative
  Randomly Featured Patents
Method for producing images in the edge of a volume of paper sheets
Method of manufacturing flat panel display
Coupling reactions of 2-substituted, 7-haloindenes with aryl substituents to produce metallocene catalyst intermediates
Method of fabricating self-aligned cross-point memory array
Hybrid remote control lawn mower
Semiconductor apparatus and manufacturing method thereof
Gas turbine air handling system
Protective coating by high rate arc plasma deposition
Method of and apparatus for managing disc defects using temporary defect management information (TDFL) and temporary defect management information (TDDS), and disc having the TDFL and TDDS
Hierarchical message addressing scheme