Applications of encoders and encoder type category characteristics

In the field of automation, rotary encoder is used to detect Angle, speed, length, displacement and acceleration sensor. Rotary encoder on shaft rod, the gear, the control of measuring wheel or cable, the linear movement can be test. Mechanical parameters of the rotary encoder and the actual value is converted into electrical signals, the electrical signal can be counter, tachometer, PLC and industrial PC treatment. Rotary encoder through internal two photosensitive accept tube into the sequence and phase relationship of Angle encoder, get the Angle encoder Angle displacement increase ( Positive direction) Or decrease ( Negative direction) 。 After the joint digital circuit especially microcontroller, incremental rotary encoder in Angle and angular velocity measurement is more absolute rotary encoder with the advantages of cheap and simple. According to the calibration method and the mode of its output signal, rotary encoder can be divided into the incremental and absolute type and hybrid 3 kinds. Incremental encoder features: incremental encoder is directly using the principle of photoelectric conversion output three square wave pulse phase A, B and Z; 90 A, B two groups of pulse phase, and thus can easily judge the direction of rotation, and Z phase for each turn A pulse, for reference point positioning. It has the advantage of simple principle structure, mechanical life expectancy can be in the tens of thousands of hours, strong anti-jamming capability, high reliability, suitable for long distance transport. The downside is unable to output shaft rotation absolute position information. Incremental encoder shaft rotates, have corresponding pulse output, the counter set arbitrary starting point, which can realize more infinite accumulation and measurement. Encoder outputs one revolution of the shaft fixed pulse and pulse number is determined by the encoder grating on the number of lines. Need to improve the resolution, can use A 90 - degree phase difference of A and B two way high resolution encoder signal frequency doubling or replaced. Absolute encoder type characteristics: absolute encoder is corresponding to the location generation output, usually as a binary code and BCD code. From the code number of the size of the changes can distinguish positive and negative position, direction and displacement of absolute zero code can also be used to power position memory. Absolute type encoder measurement range of conventional is 0360 degrees. The application of rotary encoder speed meter and length gauge generally USES the incremental encoder, introduces briefly the following with respect to its parameters, for type selection reference. （ 1) Grating line number: ( 2) Output way: common line number 30, 60, 100, 120, 200, 250, 256, 300, 360, 400, 480, 500, 512, 600, 700, 800, 900, 907, 1000, 1024, 1200, 1250, 1440, 1500, 1000, 2000, 2040, 2400, 2500, 2669, 3000, 3600, 4000, 4069, 4500, 5000, 5400, there are five conventional output mode: open collector output ( Universal) · Complementary output & middot; The output voltage & middot; The long drive output & middot; UVW output ( 3) Working voltage: conventional has the following kinds: 5 v, 12 v, 24 v, 5 - 24V（ Universal) , 5 - 30V （ 4) Protective performance: conventional type to prevent oil, dustproof, seismic. （ 5) Elastic coupling: the encoder shaft shaft coupling with users, coaxial error exists, serious when will damage the encoder. Require the use of flexible coupling, Rotary encoder manufacturers provide option) , solve the problem of eccentric, can generally be allowed torque '1 n. M, not alignment '0. 2 mm, axial Angle '1. 5 degrees. Today we are mainly about the application of rotary encoder, and the incremental encoder in the rotary encoder and the characteristics and applications of the absolute encoder, hope to help everyone's choice.