1. CNC spinning processing can be divided into contact type and non-contact type according to the readout mode encoder.

The numerical control spinning processing contact adopts the brush output, and the one brush contacts the conductive area or the insulating area to indicate whether the state of the code is "1" or "0"; the non-contact receiving sensitive component is a photosensitive element or a magnetic sensing element, In the case of the photosensitive member, the light transmitting region and the opaque region are used to indicate whether the state of the code is "1" or "0".

2, CNC spinning processing according to the working principle encoder can be divided into two types of incremental and absolute.

The numerically controlled spinning incremental encoder converts the displacement into a periodic electrical signal, and then converts the electrical signal into a counting pulse, and the number of pulses represents the magnitude of the displacement. Each position of the absolute encoder corresponds to a certain digital code, so its indication is only related to the start and end positions of the measurement, regardless of the intermediate process of the measurement.

The rotary incremental encoder outputs a pulse when it is rotated, and its position is known by the counting device. When the encoder is not moving or power is off, the internal memory of the counting device is used to remember the position. In this way, when the power is off, the encoder can't have any movement. When the caller works, the encoder can not interrupt and lose the pulse during the output pulse. Otherwise, the zero point of the counting device will shift, and this bias The amount of shift is unknown, and only the wrong production result can be known.

The solution is to increase the reference point, and the encoder corrects the reference position into the memory position of the counting device every time the encoder passes the reference point. Before the reference point, the accuracy of the position cannot be guaranteed. For this reason, in the industrial control, there are methods such as finding a reference point for each operation, and starting to change the zero.

There are many scribe lines on the optical encoder of the absolute encoder optical encoder. Each line is arranged in 2 lines, 4 lines, 8 lines and 16 lines. In this way, each position of the encoder is read by The pass and dark of the mark line obtain a unique binary code (Gray code) from the zeroth power of 2 to the n-1 power of 2, which is called an n-bit absolute encoder. Such an encoder is determined by the mechanical position of the code wheel and is immune to power outages and interference.

Absolute encoder uniqueness of each position determined by the mechanical position, it does not need to remember, no need to find a reference point, and do not have to count all the time, when you need to know the position, when to read its position. In this way, the anti-jamming characteristics of the encoder and the reliability of the data are greatly improved.

Since absolute encoders are significantly superior to incremental encoders in positioning, they have been increasingly used in industrial positioning. Due to its high precision, the absolute encoder has a large number of output bits. If parallel output is still used, each output signal must ensure that the connection is good, and it is isolated for more complicated working conditions, and the number of connecting cable cores is large. It brings a lot of inconvenience and reduces reliability. Therefore, the absolute encoder is used in multi-digit output type, and generally uses serial output or bus type output. The absolute type encoder serial output produced in Germany is usually SSI (synchronous serial). Output).