Taking the IT025 autoleveler as an example, the basic principle of its work is briefly analyzed and introduced. During the spinning process of the spinning frame, the semi-finished roving or sliver is drafted, twisted, and wound into a spinning machine. The combed sliver and the needle-carding machine combine the sliver, the needle row is drafted to improve the sliver structure, and the roving is further spun into spun yarn on the ring spinning frame, which is the main spinning machine. Grinder A spinning machine that turns fiber strands into rovings.
The main function is to draft and twist, and to wind the roving into a certain package to meet the processing requirements of the spinning frame. Carding machines are used to process cotton fibers and chemical fibers and belong to textile machinery. According to the spinning process, carding is an important process.
The front process of the carding machine is the opening and cleaning machine, and the latter process is the drawing frame (carding process) or the sliver coiler (combing process). The system composition is shown in Figure 4-24. Preferably, the A is the feeding part of the cotton layer. The cotton layer passes between the cotton plate and the cotton feeding roller. Due to the change of the thickness of the cotton layer, a sensor is displaced and the signal voltage is input to the control mechanism.
B is the part where the tampon is detected, and the weight of the tampon is detected by the movement of the tampon in the bell mouth. The control mechanism is the heart of the system. The two sensors are sampled by the control device A, B, the calculated value; then the calculation result is output to the driving cotton, the cotton, so as to control the ratio of the motor (feed roller) and variable speed operation to achieve uniform feeding of the cotton achieve the purpose of leveling.
The executive management agency can use the frequency converter to control the speed of the cotton motor. But from a control theory point of view, FT025 is formed by an autoleveler with a sensor with controller A, an open-loop actuator control circuit; sensor and controller B, with an actuator with a closed regulation loop. 2. Open-loop system algorithm After the computer network is sampled, the input signal of the cotton layer can be averaged through correlation filtering processing.
Since the fluctuation of the cotton layer needs to be frequent, in order to control the unevenness of the open loop, it is required to develop rapidly through the adjustment ability, and the fluctuation of the cotton layer feeding disc can be economically compensated by the variable speed of the cotton feeding motor, so that the cotton layer feeding amount Constant, reducing the unevenness of the cotton layer. Convert the cotton layer thickness signal in the CPU into a calculated digital quantity, and use software digital filtering. Using arithmetic mean and median filtering, the filtering algorithm can effectively eliminate the error signal on the AID sampling channel.
The hyperbolic open-loop control algorithm is used to calculate the input signal of the cotton layer thickness FT025 of the homogenizer, namely: feeding rate (constant) = feeding speed and thickness of cotton in the cotton machine x coefficient 3. The closed-loop algorithm card system has a closed-loop hysteresis element. Calculate the difference of the time series, which is used to introduce a closed-loop PID control algorithm. Among the three functions of PID, the differential action is mainly used to reduce overshoot, overcome the oscillation, the system tends to stabilize and accelerate the moving speed of the system, which improves the dynamic characteristics of the system; the integral action is mainly used to eliminate electrostatic errors, Improve static system characteristics; proportional action can respond in time to deviations. With the appropriate intensity of these three actions, the controller can run fast, smoothly, accurately and with satisfactory control effect.
4. Hardware and software (1) Hardware components: Due to the large computing disk of the internal control management system, the CPU adopts MCS96 series, 16-bit microprocessor 8098 single-chip technology and application programs for storage, data information storage, and power-off retention. The EEPROM of enterprise data, A/D, D/A conversion chip, keyboard display Chinese chip, I/O and counting timing chip constitute their own control environment system based on single-chip microcomputer, as shown in Figure 4-25. (2) Software: The main program block diagram shown in Figure 4-26. The main program is divided into parameter setting, control part of the hardware and the operation state of three functional test cycles.
When the hook is energized as a whole, it will enter the parameter setting mode where the user can set the process parameters. when parking“The user can enter the detection state to detect the various component circuits of the leveling device.