Research And Design Of Precision Independent Double Rotary Table

The precision rotary table is an auxiliary device, which play an most important role in the field of machine tool processing, angle measurement, optical measurement, inertial navigation test and so on.Many instruments and equipment in these areas are based on the multi-function, high precision, intelligence of rotary table, and according to the requirements of different extends outward expansion of advanced technology and equipment. Precision rotary table, which is based on the technical indexes of different areas, different purposes, developed by various scientific research institutes, colleges and universities, and is widely used in measurement, machinery manufacturing, aerospace and other fields. But for now, the domestic for the development of the precision rotary table, far from abroad in the field of industry, with technology level, and led to the backward in the related fields of technology, lack of theory, it was forced to import a large number of high price products. As a result, the country should increase the development costs and strenthen the power of investment on the precision rotary table urgently.This subject put forward the precision, independent, double rotary table is a kind of new type of rotary table, which has some special functions used for some special fields.For example,it can be used in the field of material analysis as a goniometer table of X-ray diffractometer. But the double rotary table has a big difference with the traditional two-axis turntable, the former is in the latter two rotating shaft system, based on the original tie their rotating shaft structure on the overlap, ensure the independence of the double turntable, and at the same time, according to the different using requirements, respectively, using two speed control of step motor as driving device, and combined with two groups with the same ratio of worm gear and worm pair of speed reducer, with different speed, direction control was carried out on the double rotary table, so as to realize including θ-θ, θ-2θ linkage function, including all kinds of rotary, dividing and positioning function independently. This structure on the overlap, we call it the concentric coaxial structure.In addition, the double rotary table also adopted the domestic new angular displacement sensor as the measuring element- Time grating angular displacement sensor. The adoption of this kind of sensor can effectively guarantee the turntable high-precision positioning requirement at the same time, greatly reduce the manufacturing cost of the turntable itself.This paper first of all, starting from the research status of precision turntable, combining with the characteristics of existing turntable type, function, development trend, this paper introduced the mechanical parts of the double rotary table design analysis, design and experimental detection circuit control part.The innovation of this article mainly has two aspects: one is the concentric coaxial structure design improvement scheme is put forward, the second is prediction model of turntable accuracy analysis using finite element method(FEM), the analysis of local change associated with the overall model of turntable.