Double-open ring control device and method applied to self-regulating technology

Abstract

The invention provides a dual opening ring control device and a method which are applied to self-adjusting regulating technology. The device of the invention comprises a rear roller, a group of middle rollers are arranged in front of the rear roller, a front roller is arranged in front of the middle rollers, a first detecting mechanism is arranged behind the rear roller, the rear roller and the front roller are respectively connected with a first executing mechanism and a second executing mechanism, a second detecting mechanism is arranged among the middle rollers, the output ends of the first detecting mechanism and the second detecting mechanism are connected with the input end of a control mechanism, and the output end of the control mechanism is connected with the input ends of the first executing mechanism and the second executing mechanism respectively. The method comprises the following steps: cotton strips firstly pass through the rear roller and the middle rollers to finish ring opening regulating for the first time, and then pass through the middle rollers and the front roller to finish ring opening regulating for the second time. The advantages of the invention are: the invention is particularly suitable for strip combining machines, and eliminates the problems existing in the original system such as blind area, dead area as well as advanced or postponed regulating.

Description

technical field [0001] The invention relates to a double open-loop control device and method applied to autolevelling technology, which is used for autolevelling of draw frame and carding machine, and belongs to the technical field of cotton textile devices and methods. Background technique [0002] Autolevelling is a form of automatic control. It can adjust the drafting device accordingly by changing the speed of the feed roller or output roller according to the deviation of the feeding or output sliver quantification, that is, the difference from the rated value. The draft multiple keeps the quantitative value of the sliver spun at a stable value that meets the requirements. Generally, the draft ratio of the machine is adjusted according to the difference between the linear density of the fed sliver and the rated value (the rated value can be determined according to the output setting value and the rated draft ratio of input and output), so that the output cotton sliver T...

AI Technical Summary

Problems solved by technology

The changes and disturbances generated in the blind area cannot be reflected in the leveling results, so the static characteristics of the open-loop system are relatively poor, and the deviations caused by various links or external disturbances after the detection cannot be automatically corrected, such as changes in yarn sliver, changes in power supply voltage , component aging, etc. Therefore, it is easy to make the final stable value drift, so that the average value of the adjusted yarn is higher or lower than the normal value

[0007] 2. Due to the long distance of the blind zone, the open-loop system cannot ensure that the time delay of the control system is properly coordinated with the time required for the sliver to pass through the detection point to the leveling point, which will cause early leveling or lagging leveling, which will eventually affect the leveling effect

[0008] 3. The open-loop system only performs targeted adjustments, and cannot verify the adjustment results

The closed-loop system cannot even the uneven yarn whose wavelength is equal to or less than the distance from the leveling point to the detection point

[0012] 2. Due to the detection after leveling, the fluctuation range of the detection is large, and the requirements for the detection equipment are relatively high, and the requirements for the motion characteristics of the leveling roller 2 that respond to the detection signal are relatively high

[0013] 3. The pertinence of the closed-loop system is not strong, and the unevenness of the middle segment often causes the system to malfunction, but worsens the uniformity of the middle and short segments

Because the draw frame requires a very short even segment (such as the USC system of UST ER can reach 15-20mm, especially to eliminate the unevenness caused by the lap in the combing process; and the drawing speed of the draw frame is very fast, Foreign draw frames have reached 1000m / min, and domestic draw frames have also reached 600m / min. In this case, it is very difficult to accurately detect the output sliver line speed. According to the actual use of the factory, it is impossible to accurately detect the output sliver. Line speed, it is impossible to form a closed loop, predictive control theory cannot be used, and predictive control theory algorithm is more complex, it is difficult to realize the automatic leveling system of the draw frame with too high real-time requirements

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