Method and device for feeding a yarn or thread to a processing machine with constant tension and velocity

A device for feeding a spoolable material to a processing machine at a desired tension and at a desired velocity,

• wherein the desired tension is within a desired tension range,
• wherein the desired velocity is constant and equal to a self-determined or predefined and programmable value,
• the device comprising:
• a control unit,
• a velocity sensor monitored by the control unit,
• a tension sensor monitored by the control unit,
• an actuator controlled by the control unit, and
• a rotary member driven by the actuator,
• wherein the spoolable material cooperates with the rotary member and extends from the rotary member to the tension sensor;
• the control unit being adapted to:
• monitor, via the tension sensor, a measured tension of the spoolable material between the device and the processing machine;
• monitor, via the velocity sensor, a measured rotational velocity of the rotary member;
• control, based on the measured tension, the actuator to drive the rotary member to attempt to attain the desired tension;
• upon attaining the desired tension, control, based on the measured rotational velocity, the actuator to drive the rotary member to attempt to attain the desired velocity;
• and
• upon deviating from the desired tension, control, based on the measured tension, the actuator to drive the rotary member to attempt to attain the desired tension,
• wherein if both tension and speed are constant, the control unit feeds the yarn at constant speed.

A method of feeding a plurality of spoolable materials to a processing machine via a plurality of devices, each at a desired tension and at a desired velocity,

• wherein each desired tension is within a desired tension range,
• wherein each desired velocity is constant and equal to a self-determined or predefined and programmable value,
• each device comprising:
• a control unit,
• a velocity sensor monitored by the control unit,
• a tension sensor monitored by the control unit,
• an actuator controlled by the control unit, and
• a rotary member driven by the actuator,
• wherein each of the plurality of spoolable materials cooperates with a respective rotary member and extends from the respective rotary member to the tension sensor;
• the method comprising using each control unit to:
• monitor, via the tension sensor, a measured tension of one of the plurality of spoolable materials between one of the plurality of devices and the processing machine;
• monitor, via the velocity sensor, a measured rotational velocity of the respective rotary member;
• control, based on the measured tension, a respective actuator to drive the respective rotary member to attempt to attain the desired tension;
• upon attaining the desired tension, control, based on the measured rotational velocity, the respective actuator to drive the respective rotary member to attempt to attain the desired velocity;
• and
• upon deviating from the desired tension, control, based on the measured tension, the actuator to drive the rotary member to attempt to attain the desired tension,
• wherein if both tension and speed are constant, the control unit feeds the yarn at constant speed.