Theoretical Research Of Ballscrew Manufactured By Cold Rolling

Because the ballscrew hitherto has the following characteristics: high transmission efficiency, good smoothness of motion, high reliability etc., it has been applied to machinery, aviation, nuclear industry and other fields. With product application range expanded and its own advantages which makes the ballscrew occupy the vast majority of the market. Because the domestic processing capacity is limited, the large number of foreign products occupies a large part of the domestic market. So the study and development on new processing methods of ballscrew is necessary.In this paper the main research contents are as follows:1. The motional relation model of ballscrew manufacture by cold rolling has been investigated based on the kinematics theory of part surface forming motion. The simulation of rotation angular velocity is made by means of ADAMS. The correct motion relationship can be got through comparison between theoretical value and simulation result.2. According to the movement relationship of cold rolling, the coordinate of cold rolling and mathematical model of cold rolling have been established. On the basis of mathematical model of cold rolling, the flank equation and contact line equation have been built. The objective moving laws between the roller and the workpiece has been revealed by analyzing the flank and contact line.3. According to error theory the error models of normal profile and the actual helix of the center track of ball and surface roughness have been built. The change of error and the error cause and the method of error elimination have been obtained through analysis of the normal profile error. By analyzing of the ball center track error the error generation causes and the measures of error elimination can be got. By analyzing of surface roughness of spiral race the factors of influencing surface quality have been got. The effective ways of improving processing quality can also be got. 4. According to the relationship of cold rolling and the engagement principle, the model of the axial section has been built. Through comparing the design normal profile and forming normal profile the comparison result proves that the design of roller has been proved correctly.5. On the principle of the constancy of volume the calculation of the blank diameter has been derived. Using that roller of shaping method design makes finite element simulation of ballscrew under different process parameters; the reasonable process parameter can be got. Through analysis of simulation result the forming law of blank can be obtained in the process of cold rolling. The error law can be obtained through comparing process tooth profile to theoretic normal profile, which can be shown correctly once again.6. The tests of cold rolling are done to copper rod and aluminum rod using the improved CA6140. The test results indicate the technology of cold rolling applied to ballscrew machining is feasible. KEY WORDS: ballscrew; superficial shaping of parts; cold rolling; surface roughness;...