Kinco Servo Application on Gold Wire Drawing Machine

I. Overview

The drawing machine system is a mechanical device that requires very high speed control and requires the control system to provide very accurate and smooth line speeds. The wire drawing machine used for drawing gold is more demanding than the ordinary wire drawing machine. The entire system is more complex and there are many control devices, and high coordination between the motors is required. The system uses four sets of servo motor control, and each set of servos has real-time data exchange. The bus communication capability supported by Kinco servo can fully meet the real-time data interaction between each axis.

In view of the requirements of the system to quickly interact with data between motor shafts, in order to ensure that the wire can quickly calculate the track and wire placement in accordance with the required algorithm, we also make full use of the internal firmware function of the kinco servo, self-calculating by the drive, self-driven motor The wire arrangement greatly omits the time delay caused by the traditional wire drawing machine control system to calculate the position of the wire through the controller and then to the drive, and ensures the minimum delay of the wire. This system is briefly introduced below.

Second, the system block diagram

Third, the process

1. The undrawn gold wire passes through a resistance device (mainly a plywood or the like, which is used to provide a certain tension, but also plays a role in preventing line jumps), and then enters the fine drawing groove;

2. The gold wire that has entered the fine drawing groove becomes the required wire after multiple drawing of the fine puller wheel and the micro-later wheel (from coarse tapering), and a grinding tool is placed on the partition between the two towers. The shape of the abrasive tool is "", that is, the hole is thick on one side of the hole;

3. The attenuated wire passes through the slip wheel. The function of this wheel is to maintain a constant tension.

4. The gold wire after coming out of the slip wheel passes through the speed measurement theory. The role of the speed wheel is to measure the current wire speed for feedback.

5. The gold wire of the speed measuring wheel passes through an intermediate link, then passes the swinging screw rod, and finally winds the wire onto the winding wheel;

Fourth, the system control framework

Frames:

The main control difficulties of the entire system are mainly the following four parts:

1. Constant wire speed control for wire feeding servo;
2. Adjust servo following control;
3. The constant speed (constant tension) control of the winding servo, that is, the winding servo is required to maintain the linear speed equal to that of the servo when the radius increases continuously;
4. Position servo control

Since the system requires CANopen bus communication capabilities, and after considering the existing CANopen controller solutions of various domestic manufacturers, we chose Schneider's Twido series PLC and CANopen module.

Fifth, the control program introduced

1. Constant wire speed control of "feed wire servo"

The control of the servo motor is performed using a control mode with acceleration/deceleration (Kinco servo speed 3 mode). For this system, it is required that the main shaft wire-discharging motor is capable of maximally resisting disturbances and operates at a stable speed as much as possible, and due to the requirements of the wire drawing process, it must be ensured that smooth acceleration and deceleration functions are provided when it is stopped or stopped. The driver works in the speed 3 mode, and it can fully meet the requirements for extremely stable speed control.

2. "Adjust servo" following control

The servo motor is controlled using the following control mode (-4 mode). The motor control requirements are extremely high, and its speed needs to be completely followed by the wire-wound motor. If there is a large deviation, the gold wire will be broken, and this is not allowed for the gold wire drawing system! . When Kinco servo drive works in “-4” mode, it has very precise and sensitive speed following performance. Not only can it meet strict follow-up requirements, but it can also dynamically modify the following gear ratio to achieve linear fluctuations of ±5%. Ensure tension).

3. Constant speed (constant tension) control of winding servo

The control of the motor is the most important point of the entire system. In order to smooth out the line and not collapse, the linear speed of the winding motor is equal to the linear speed of the adjusting motor. To achieve constant line speed control, a feedback loop must be used to detect the actual reel's line speed. The customer's past system uses the tension bar to complete the tension. The tension bar feeds back a tension signal, and the tension bar has a In the intermediate transition period, if the difference between the linear speed of the winding motor and the linear speed of the adjusting motor is relatively large, the mechanical structure is first compensated, and then the electrical compensation is added, which is equivalent to two compensation links, and the broken wire is reduced. Probability. Such a system is used in many wire drawing machines. At present, this wire drawing machine is specially used for drawing gold wire. The surface of gold wire requires a very high degree of cleanliness. It is necessary to minimize the intermediate excessive links. Therefore, the customer cancels the tension lever and directly uses the speed measurement wheel as a feedback loop. This increases control.

First of all, we collected the linear velocity of the tachometer wheel through the signal, then through the comparison with the linear velocity of the adjusting wheel and through our PID calculation, finally added the calculation result to the current winding wheel speed. In addition to calculating the speed of replenishing the winding wheel through real-time PID calculation, we also calculated the number of winding layers as the basis for calculation when controlling the winding speed of the winding wheel, thereby ensuring that the winding wheel will not be caused by the continuous increase of the diameter. Causes an increase in errors.

4. Servo Position Control

The servo control of the tilting wire is mainly to ensure that the wound wire is evenly arranged on the bobbin. The following figure shows the effect of the wire stranding required:

The difficulty of this motor control lies in the commutation part. In order to smooth over the commutation without threading, the motor must be ensured to avoid accumulative errors during commutation. Due to the absolute positioning mode of Kinco servo, internal calculation of the firmware is used to ensure The absolute positioning is completed in the last lap.

Sixth, concluding remarks

At present, the system has been put into production and it has been running for about 2 months continuously with good results. The spindle speed can be up to 400 rpm when drawing 3 wires (finished diameter), which is nearly 5 wires faster than the gold wire drawn by the machine using the tension rod feedback loop, and the speed is nearly 70 rpm, and the drawn Gold wire surface smooth, fully meet customer requirements.

PU Resin For Dry-Process Surface Layer

Dry Process Pu Resin,Label Leather Polyurethane Resin,Synthetic Leather Polyurethane Pu Resin,Pu Resin For Leather Making

XUCHUAN CHEMICAL(SUZHOU) CO., LTD , https://www.xuchuanchem.com