Grating Ruler Sensors Makes PNP E1 More Precisely

Traditional pick and place machines only use stepper motors:

The control of stepper motors is open-loop control. If the starting frequency is too high or the load is too large, it is easy to lose steps or stall. When the speed is too high, it is easy to overshoot. Therefore, to ensure accuracy, it should be handled well the speed. When the device is out of step, the machine can't discover it, causing the displacement deviation of the effect of pick and place, causing the overall displacement deviation of the placement effect, and the device can only be restarted and initialized.

E1 adds a grating self-feedback closed-loop system on the original basis:

The grating ruler displacement sensor (abbreviated as a grating ruler) is a measurement feedback device that uses the optical principle of grating to work. The missing pulse can be automatically corrected through the cooperation of the grating ruler and the reading head, and feedback to the controller can be time also when the rotor is locked.

Figure 1. The placement effect when the stepper motor loses steps

Figure 2. The final placement effect of adding the grating self-feedback closed-loop system to automatically correct the missing pulse

Figure 3

Figure 3 is the grating ruler reading head which will give feedback to the stepper motors. Stepper motors will adjust themselves in real-time.

Figure 4

Figure 4 is the grating ruler.

The installation of the grating ruler is extremely strict:

1. When installing the reading head, first ensure that the base surface of the reading head meets the installation requirements, and then install the reading head. The installation method is similar to that of the grating strip. Finally, adjust the reading head so that the gap between the reading head and the grating strip is controlled within 1~1.5mm.

2. The grating strip must be installed horizontally and vertically without any bending.

3. The grating ruler is not easy to be too long, which leads t

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