Printers, printer spindle assemblies, and methods for determining media width for controlling media tension

A printer comprising:

• a spindle assembly comprising:
• a media spindle having a first end and a second end;
• a commutator disposed circumferentially at the first end of the media spindle;
• at least two brushes in electrical contact with the commutator and connected to a voltage source, the voltage source, the at least two brushes, and the commutator forming a closed electrical circuit;
• a plurality of electrically conductive springs serially disposed on the media spindle in electrical communication with the commutator, wherein each electrically conductive spring is configured to be in an uncompressed state in the absence of media on the media spindle and one or more of the conductive springs is configured to be in a compressed state in the presence of the media on the media spindle;
• and
• a continuous electrically conductive path formed of electrically resistive material disposed along a longitudinal axis of the media spindle and configured to be in electrical contact with a first spring end of the one or more electrically conductive springs in the compressed state to form a series circuit;
• and
• a processor configured to determine a width of the media loaded on the media spindle based on the resistance of the series circuit and configured to adjust torsion on the media based upon the determined width of the media.

A method comprising:

• loading media on a media spindle of a printer spindle assembly, the media spindle having a first end and a second end and the printer spindle assembly comprising:
• a commutator disposed circumferentially at the first end of the media spindle;
• at least two brushes in electrical contact with the commutator and connected to a voltage source, the voltage source, the at least two brushes, and the commutator forming a closed electrical circuit;
• a plurality of electrically conductive springs serially disposed on the media spindle in electrical communication with the commutator, wherein each electrically conductive spring is configured to be in an uncompressed state in the absence of the media on the media spindle and one or more of the electrically conductive springs is configured to be in a compressed state in the presence of the media on the media spindle;
• and
• a continuous electrically conductive path formed of electrically resistive material disposed along a longitudinal axis of the media spindle and configured to be in electrical contact with a first spring end of the one or more electrically conductive springs in the compressed state to form a series circuit;
• connecting the at least two brushes to a voltage source;
• determining an electrical resistance of the series circuit;
• and
• determining, from the electrical resistance, a width of the media loaded on the media spindle.