How to accurately depict the curve of the warp-knitted horizontal bar

Update:14-08-2019
Summary:

In order to obtain the corresponding relationship betwe […]

In order to obtain the corresponding relationship between the warp speed and the spindle speed in real time, it is necessary to make several changes to the hardware part of the electronic warp control system. First, the feedback pulse sent to the servo driver should be connected to the counter of the control unit to directly calculate the rotational speed of the warp beam motor. Secondly, it is necessary to connect the warp knitting machine stop signal to the output relay of the control unit, so that the upper machine can control the stop of the warp knitting machine. In order to obtain the signal of the spindle encoder in real time, it is also necessary to directly connect the pulse output signal line of the spindle encoder to the input command pulse train pin of the warp beam servo driver.
 
Sampling program design

During the driving process, the host computer issues a driving command, and the control card in the control unit receives the command, so that the normally open contact of the driving relay is closed, the warp knitting machine starts driving, and the spindle starts to run. The control card starts the timer while closing the relay contact, and turns on the warp pulse counter and the spindle pulse counter to start counting. The timer period is 10ms. When the timing time is up, the counter is turned off, the counter value is read, the spindle and the warp beam speed are calculated, and the clock is transmitted to the upper computer, and then the timer is restarted, and the cycle is sequentially performed. While the host computer issues the driving command, it uses the host computer timer to start querying the control board whether to send the spindle and warp beam speed data in 1ms cycle. If so, the two data and the corresponding time are written to the log file.

When parking, the host computer issues a parking command, and the control card in the control unit receives the command, so that the normally closed contact of the parking relay is disconnected, and the warp knitting machine stops, and the spindle continues to operate for a period of time due to inertia. After completely stopping, stop reading the control card data, close the file, and record the time and speed data of one open stop.

Result analysis

According to the test principle, through the above program design, the corresponding relationship between the warp shaft speed and the spindle speed at various vehicle speeds is sampled on the HKS3-M high speed warp knitting machine.

in conclusion

1) Reasonable transformation of the hardware part of the existing electronic let-off system, and the digital sampling program can accurately obtain the following relationship between the spindle and the warp beam speed.

2) Analyze the data sampled by the above digital test method to accurately depict the curve of the warp-knitted horizontal bar.

3) The test results show that the direct cause of the warp knitting rail is the change of the warp speed and the change of the spindle speed; the width range of the warp parking rail is related to the speed of the normal operation, the greater the speed, the horizontal bar The wider the shape of the warp-knitted horizontal bar is related to the change of the rotational speed of the main shaft, the high-speed parking spindle has large fluctuations in the rotational speed, and the horizontal bar elastic changes frequently.

4) The results of this test can be directly used to improve the control algorithm of electronic delivery, to maximize the elimination of parking bars

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