Design Of New Type Of Magnetic Multi - Turn Absolute Encoder

Today, automatization is springing up, that causes lots of need in the measuring tool. In many situations it is too long to locate the exact position directly by linearity measuring instrument. So the indirect measuring method,that uses the multi-loop absolute encoder to measure the rotation angle of the shafts winded by the moving strip or rope is very widely used. However, the multi-loop absolute encoders are hard to be made and the prices are very high in the market at present. In this paper a new multi-loop encoder instrument is introduced, which consists of a reducer and a circuit board mounted with AS5045 s array. This encorder has large measuring range, high resolution, high rotation speed, nice stability, and especially low produce cost. This instrument also can be chosen to work in different output modes with position, angle speed, and angle acceleration, and different output modes in output value format.This paper concentrates on the central part of the equipment, multi-loop encoder. In the front part of the dissertation the author, first, analyzes the situation of the encoder device at present, then introduce the core sampling device AS5040, and then discusses the way the instrument running, at last chooses the gear reducer mechanism type used in the instrument. There are two main sections in this paper, the mechanism design and the circuit design. In the mechanism system of the instrument, the gear reducer system design is optimized to obtain the smallest rotation inertia and the biggest reducing ratio. At last, the transmission error is studied in detail to identity the error sources and their magnitude, that may affect the encoder system seriously. In the circuit design, the whole hardware includes the sampling modules of AS5040 s array, the information transmission interface and the data processing unit. The software includes the data processing program and the interface program. In the data processing program, to solve the critical problem of mechanism encoding, a special processing program is designed. For the facility to the customs, different output modes are given.