Traditional system solution of false twisting machines: PLC includes all sorts of control. It can collect data, control the temperature of heating boxes and set operation frequency of inverters. However, the cost of electrical control system is high. The article introduces a new integrated system solution of false twisting machines, where inverter control and constant temperature control are added and control algorithm is optimized. The solution is simple and convenient, ensures the accuracy on temperature of heating boxes and improves equipment stability.
Keywords: Inverters; False twisting machine; Integrated system solution
I Introduction of false twisting machine processes
The main function of false twisting machines is to twisted loose wires into closely arranged thick wires and increases their flexibility. Its main processes are divided into two-for-one twisting, heating, false twisting and winding.
The mechanism of false twisting machines is made of 24 same units. Every two units form a group. Every group can process 16 yarns. Every group consists of two-for-one twisting, winding, traversing, false twisting and heating.
1. Two-for-one twisting: Two-for-one twisting is to twist the yarn. Twist of yarn is determined by spindle speed and winding speed.
2. Heating: It heats the yarn with constant temperature.
3. False twisting: False twisting adds flexibility to the yarn and is made of a motor, belts, driven pulleys and false twisters. Pulleys are driven by the belt in certain speed.
4. Traversing: It prevent the yarn from overlapping in each layer before it winds on the coiling block. Traversing is made of a motor, the traversing mechanism and the yarn guide.
5. Winding: It is made of a motor, gears, the up and down overfed roller, the pulling roller and the drum roller.
II. Electrical control scheme
Electrical control system of false twisting machines usually need a touchscreen, a PLC, 2 PLC analog modules and 4 inverters (their power is respectively 11, 7.5, 1.5 and 1.5KW). With the increasing cost and decreasing selling price of false twisting machines, the profit space is narrowing. According to market conditions, SIMPHOENIX Electric launched the integrated system solution of false twisting machines to satisfy market needs.
The solution adopts 4 inverters, an expanding card and a touchscreen to realize all the functions of original solution. Solution structure is clear and wiring is simpler. It nearly saves 20% electrical control system costs.
Figure 2 Integrated Structure Diagram of False Twisting Machine in Its Integrated System Solution
The control schematic of electrical integrated solution in false twisting machine electrical is shown in the following figure:
Process parameters such as operation temperature of inverters and set temperature of heaters are set on the touchscreen by RS-485 communication. Temperature sensors are used for feedback in the heater. Expanding card is used for PID calculation adjustment. All work together to control heater temperature and guarantee constant temperature control in the whole system.
1. Definition and storage of data signals
Operation frequency, acceleration and deceleration time, two-for-one twist and false twist of 4 inverters are set on the touchscreen through RS-485 communication. Expanding card has storage function to store process parameters.
2. Temperature control of the heater
V360 expanding card sets heater temperature through touchscreen, sets collected temperature analog signal as the feedback and realizes constant temperature control of the heater by means of PID.
3. Realization of disturbances
In order to prevent overlapping of the yarn in winding, traversing motor adopts pendulous frequency function to let yarn evenly winding around the coiling block.
4. Recording of fault alarms
During the operation of false twisting machines, equipment will more or less fail or give out alarms, such as temperature alarms of the heater and inverter failure. The touchscreen will recorde the information for the operator to check.
III. Comparison of solutions
Equipment stability determines the quality of a system solution, which determines system configuration.
Item for comparison
FUNFAR Electrical Integrated Solution
|Electrical configuration||4 inverters, a expanding card, a touchscreen||A touchscreen, a PLC, 2 PLC analog modules, 4 inverters||Saving nearly 20% of the costs|
|Steady speed accuracy||±0.5%||±0.5%|
|Constant temperature control||±2℃||±2℃|
|Instant low voltage||Voltage of inverters can be as low as three-phase 250V||Inverters often give alarms in low voltage.||Better voltage stabilization|
The solution is applied to false twisting machines in actual production an guarantees temperature control accuracy of the heater, improves system stability and reduces electrical system costs. Practice has proved that the solution is a kind of cost-effective electrical integrated solutions in false twisting machines satisfying modern processing needs.
Post time: Sep-17-2018