Motor Control Device for Roll Paper Tension Stabilization

The patent combines two motors (roll motor and paper feed motor) to work together on the same mechanical system. The roll motor rotates the roll to supply paper, while the paper feed motor transports the paper through the transport roller pair. This merging of driving forces allows the system to handle the heavy roll and high load without tearing the paper, while still maintaining reasonable device complexity through coordinated control.

The patent implements feedback control by measuring the actual tension between the transport roller pair and the roll, and using this measurement to adjust the roll motor output. The microcomputer controls the roll motor to maintain constant tension despite changes in roll diameter and weight. This feedback mechanism transforms the simple constant output control into an adaptive control system that maintains tension stability.

The patent changes the control parameter from constant output to tension-based adaptive output. When the roll weight is reduced, the system detects the resulting tension deficiency and automatically increases the roll motor output to compensate. This parameter change allows the system to maintain appropriate tension force regardless of whether the roll is heavy or very light, solving the problem of loose paper with lightweight rolls.

The patent performs preliminary tension stabilization before printing begins. The microcomputer controls the roll motor to establish and maintain constant tension between the transport roller pair and the roll throughout the printing process. By preemptively stabilizing the tension condition, the system ensures that subsequent printing operations occur under stable conditions, thereby maintaining high print quality while adapting to different roll states.