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
Liquid hardening
Secondary marketplace for digital media content
Non-aqueous electrolyte secondary battery, electrode used for secondary battery, and method of manufacturing electrode
Stereoscopic images generated by adding content to alternate eye images for retinal rivalry
Illuminated eyeglasses
Cigar cutter
Configuring a computer system for a software package installation
  Randomly Featured Patents
Catalyst system and process for polymerization of conjugatged dienes therewith
Wireless speaker with base for portable phone
Low density tantalum anode bodies
Method for handling and processing microelectronic-device substrate assemblies
Window operator having a linear drive mechanism
Illuminated bank window
Protective carrier for microcircuit devices
Meter mounting bracket
Solar control glazing
SOI device having an increasing charge storage capacity of transistor bodies and method for manufacturing the same