Ribbon tension control system and method for a ribbon printing system

A method for controlling tension in a print ribbon of a printing system, the method comprising:

• winding the print ribbon from an unwind spindle to a windup spindle, the print ribbon at least partially passing through a ribbon tension control apparatus,
• pulling the print ribbon through the printing system from the unwind spindle to the windup spindle by applying a torque from the windup spindle, the print ribbon pulled between a print head and one or more target objects to be printed upon by ink in the print ribbon when the print head engages the print ribbon;
• and
• controlling the tension in the print ribbon as the torque applied by the windup spindle changes by at least one of changing a path that the print ribbon follows through the printing system or varying a braking force applied to the unwind spindle,
• wherein controlling the tension in the print ribbon includes varying the braking force applied to the unwind spindle in response to changing the path that the print ribbon follows through the printing system, and
• wherein controlling the tension in the print ribbon includes moving an articulating arm that is pivotally mounted in the printing system and coupled with a brake that applies the braking force along a cam lobe that pivots responsive to changes in the torque applied by the windup spindle, the articulating arm pulling on the brake when the articulating arm moves along the cam lobe in a first direction to increase the braking force.

A tension control system of a thermal ribbon printing system, the tension control system comprising:

• a cam lobe pivotally mounted in the thermal ribbon printing system;
• a dancer roller coupled with the cam lobe;
• a tension control member anchored in the thermal ribbon printing system and coupled with at least one of the cam lobe or the dancer roller;
• an articulating arm pivotally mounted in the thermal ribbon printing system, the articulating arm engaging the cam lobe;
• and
• a brake coupled with the articulating arm and configured to engage at least one of an unwind spindle or a flange coupled to the unwind spindle of the thermal ribbon printing system to apply a braking force to the unwind spindle, wherein a thermal print ribbon extends from the unwind spindle, at least partially around the dancer roller, between a thermal print head and one or more target objects to be printed upon by the ribbon, and to a windup spindle, and
• wherein, when the windup spindle applies a time-varying force to pull the ribbon through the thermal ribbon printing system, the cam lobe pivots to permit the dancer roller to laterally move in the thermal ribbon printing system and the tension control member applies an opposing force to resist the dancer roller laterally moving, and
• wherein pivoting of the cam lobe causes the articulating arm to pivot, which changes a pulling force applied to the brake in order to vary the braking force.