Delivery device for delivering yarns, method for determining the tension of yarns and use of control means for controlling actuators for delivering yarns

Method for monitoring tensions of several yarns which are delivered in a textile machine by means of several actuators, characterized in that said method comprises delivering each of the several yarns using only one of the several actuators, producing measurement signals for each actuator as a measure of drive torque of said actuator, wherein the yarn tension can be calculated from the drive torque, and monitoring the tensions of the yarns using said measurement signals, wherein the several actuators are electrical actuators, and wherein the measurement signals are generated based on measured current in each of the several actuators and/or measured voltage across each of the several actuators,

• wherein monitoring comprises, for at least one determined drive torque, comparing the determined drive torque to an upper value and producing an indication if the determined drive torque exceeds said upper value;
• comparing the determined drive torque to a lower value and producing an indication if the determined drive torque drops below said lower value;
• comparing a change in successive determined values of the drive torque to a reference value;
• and producing an indication if the change exceeds this reference value.

A method, comprising:

• using controllers to control actuators for delivering several yarns in a textile machine, wherein each of the several yarns is delivered using only one of the actuators, wherein the controllers are configured to produce measurement signals for each actuator which are a measure of drive torque of said actuators wherein tensions of the yarns can be calculated from the drive torque, wherein the actuators are electrical actuators, and wherein the measurement signals are generated based on measured current in each actuator and/or measured voltage across each actuator;
• and
• monitoring the tensions of the yarns using the measurement signals, wherein monitoring comprises, for at least one determined drive torque, comparing the determined drive torque to an upper value and producing an indication if the determined drive torque exceeds said upper value;
• comparing the determined drive torque to a lower value and producing an indication if the determined drive torque drops below said lower value;
• comparing a change in successive determined values of the drive torque to a reference value and producing an indication if the change exceeds this reference value.