Fixed length control system of the hottest aluminu

The fixed length control system of aluminum foil slitting equipment

modern aluminum foil slitting equipment not only requires stable speed and constant and adjustable tension, but also stops quickly and accurately under the set length according to the requirements of the draft, especially for cable foil or electronic foil, which requires a certain length of foil roll. This is guaranteed by the fixed length control

the structural diagram of aluminum foil slitting equipment is shown in Figure 1. Among them, the guide roller, shear device, pinch roller, separation roller, etc. are connected with each other through the synchronous toothed belt, which is uniformly called the central shaft. Like uncoiler, left coiler and right coiler, it is driven by corresponding DC motor. The incoming materials are loaded on the uncoiler and wound on the left coiler and the right coiler respectively after passing through the guide roll, shear device, pinch roll and separation roll. According to the process requirements, the reel of the coiler is always pressed on the separation roll during the production process. Install an induction body a on the circumference of the end face of the shaft end on the non driving side of the separation roller, the induction surface of a is perpendicular to the end face of the shaft, and install two proximity switches B and C at the radial position of the shaft end. There is no special requirement for the angular distance between B and C, but its induction surface is parallel to the induction surface of a, and the correct action distance is guaranteed, so as to form a fixed length control system

1 fixed length control principle

in Figure 2, the PLC adopts C60P machine produced by OMRON company, which controls the running state of the whole train; H7br is a six digit decimal all process produced by om-ron company. It can visualize a digital counter crawling on the spider (WEB) for a spider. It can set each bit and display the set value and count value; It has two independent counting signal inputs (CP1, CP2) and two corresponding outputs (ou6. Transmission spindle T1, out2). In this system, the first channel is used for the speed reduction control of the train, and the second channel is used for the parking control of the train. Fixed length control is based on it

the diameter of the separating roller in Figure 1 is 213.04mm. When it rotates one circle, the aluminum foil advances 668.94mm, and the proximity switches B and C send out a pulse respectively. Each path is counted separately. The calibration coefficient between the pulse count value and the aluminum foil length is set to 1.496, that is, when 1.496 pulses are included, the aluminum foil length count increases by 1m. In this way, when a suitable length is reached, out1 acts and sends a speed reduction signal to make the train run stably from the current speed to a lower speed; When approaching the required length, out2 acts and sends a stop signal to realize accurate parking and reach the required length. The deceleration and shutdown curves are guaranteed by the transmission system of the train

2 function of h7br

h7br is equipped with microprocessor and memory, built-in battery, and can still set its input and output mode, action duration, counting speed, minimum reset time, decimal point position, preset scale factor, key protection range and other working states without corrosive medium, obvious source and electromagnetic interference without providing working power supply. It can also be operated through its terminals: such as prohibit counting, count value and output action reset, key protection, etc

h7br has a wide range of working power supply and can provide DC12V or 24V power supply to the outside

3 application of h7br in fixed length control

the maximum speed of the aluminum foil slitting equipment produced by our company is 800m/min, that is, the maximum frequency of pulses sent by each proximity switch is 20Hz. The maximum counting frequency of h7br is 10kHz, and the user's requirements for the length of foil roll are within the range of six digits. It can be seen that h7br can meet the requirements in both counting speed and counting range

according to the operation instructions of h7br, after correctly setting its working state, set the action values of out1 and out2 on its panel according to the production requirements. The setting of speed reduction point of out1 train should be considered according to the highest speed of the train, so that the train can smoothly reduce from the current speed to a lower speed, such as 50m/min (if the current speed is less than 50m/min, it will rise to 50m/min). The time of raising and decelerating of the train is 45s. When the highest speed is 800m/min, the absolute value of the acceleration and deceleration is 0.2963m/s2. The train is reduced from 800m/min to 50m/min, the length of aluminum foil passing is 298.828m, from zero speed to 50m/min or from 50m/min to zero speed, and the length of aluminum foil passing is 1.172m. Therefore, the action value of deceleration point (out1) is set as the required length minus "300", and the action value of parking point (out2) is set as the required length minus "1"

4 conclusion

the negative tolerance required by users for the length of foil coil is zero, and the positive tolerance is 0.3% to 0.5%. The length determination accuracy of this system can reach 0.1%. The production practice of users over the past few years has proved that the system fully meets the requirements put forward in the design index, meets the production needs, and is completely feasible. Compared with selecting high-grade PLC, configuring high-speed counting unit, pulse encoder, dial switch, seven segment digital display, etc., this greatly reduces the equipment cost and simplifies the system design. At the same time, the accuracy of fixed length control will be further improved by increasing the number of inductors a or reducing the diameter of the measuring roll (the separation roll in this equipment)

h7br also has many other functions, such as batch processing, which can be applied according to different control needs