Control of a ring spinner, with a sliver drawing unit, has separate motor control sections to give a delay to the drawing unit operation until the spindle speed is at the working level on a start-up

摘要

To control the operation of a spinner with a spindle drive, and especially a ring spinner with a sliver drawing unit, a central control unit is used with two motor control sections. In the control action, the second motor control or the drawing unit drive motor is initially run very slowly for a given time span to give a maximum acceleration by the lower drawing roller of 0.5 s-2, with a linear or exponential acceleration ramp. On achieving a given sliver delivery from the drawing unit in a time span, the acceleration is increased to a maximum of 5.5 s-2 and at least 3 s-2. To control the operation of a ring spinner with a sliver drawing unit, after the spindle drive has been switched on, the drawing unit remains switched off for a time span. While the drawing unit drive is accelerated, the drawing unit is brought to a sliver delivery rate which matches the rotary speed of the spindle for the parameters of the yarn to be spun. The spindle is accelerated strongly from the start-up to beginning of the time section with the drawing unit disconnected, while a delay unit blocks the drawing unit control with a zero frequency from the frequency transmitter. When the spindle and the drawing unit have reached their operating speeds, a cycle frequency is set for the drawing unit which is proportional to the cycle frequency for the spindle. In addition, a delay time of up to 3 secs. can be set for an individual drawing unit cylinder at the outlet side against the other drawing cylinders, which are delayed by 0-1 sec., to prevent an overstretch of the sliver material. The three time sections have a duration of 0-8 secs., 1-3 secs., and 1-5 secs. An Independent claim is included for a control system for a ring spinner, with a sliver drawing unit, with a motor control unit for the spindle drive, and a second which controls the drawing unit drive, with a controlled delay action on a start-up. Preferred Features: A matching unit is linked to a frequency transmitter which gives the cycle frequency.