Accuracy of Spindle Units with Hydrostatic Bearings

Abstract

The work is devoted to the research ofprecision regularities in a spindle unit by the trajectory of the spindle installed on hydrostatic bearings.The mathematical model of trajectories spindle with lumped parameters that allows to define the position of the spindle with regard the simultaneous influence of design parameters, geometrical deviations ofform, temperature deformation bearing surfaces, the random nature of operational parameters and technical loads of hydrostatic bearings has been developed. Based on the results of numerical modeling the influence of shape errors of bearing surface of hydrostatic bearing on the statistical characteristics of the radius vector trajectories of the spindle by varying the values rotational speed of the spindle and oil pressure in front hydrostatic bearing has been developed. The obtained statistical regularities of precision spindle unit have been confirmed experimentally. It has been shown that an effective way to increase the precision of spindle units is to regulate the size of the gap in hydrostatic spindle bearings. The new design of an adjustable hydrostatic bearing, which can improve the accuracy of regulation size gap has been proposed.

Identification of Analytical Dependencies of the Operational Characteristics of the Workpiece Clamping Mechanisms with the Rotary Movement of the Input Link

“…Compute of the value of the work efficiency coefficient of clamping mechanisms with the electromechanical actuator derives from putting dependencies (10), ( 15), ( 17) into (8). Choosing appropriate characteristics of the elements of the new structure conduces to elimination of the problems related to increasing efficiency of fixation of a workpiece for high-performance machining.…”

Assembly Error Tolerance Estimation for Large-Scale Hydrostatic Bearing Segmented Sliders under Static and Low-Speed Conditions

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Use of Jet Technologies for Force Action on the Shaft of a Hydrostatic Bearing

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