Linearization of the static negative compliance function of a hydrostatic thrust bearing with an elastic flow regulator

This article discusses a hydrostatic thrust bearing with an elastic lubricant flow rate regulator. By utilizing the capabilities of this regulator, the bearing is capable of providing negative compliance of the supporting lubricant layer. Using such a bearing in metal-cutting machine tools in negative compliance modes allows for the simultaneous functions of a supporting structure and a deformation compensator for the machine’s elastic system. A method for linearizing the bearing’s load characteristics over the operating range of loads is proposed and theoretically substantiated. Using a bearing with constant negative compliance and a linearized load characteristic ensures the combined zero compliance of the machine tool and bearing, thereby increasing precision and minimizing machining time. The study was conducted using dimensionless parameters and characteristics. Formulas have been obtained for calculating lubricant flow through the adjuster and lubrication gap, bearing load-bearing capacity, bearing layer thickness in the lubrication gap, and the compliance of the bearing layer of the structure over the entire range of applied loads. Formulas have been derived for smoothing out the steps in the load characteristic that form during its linearization over the operating load range. A formula for the elastic adjuster bore profile has been derived that ensures the bearing will have constant compliance and a linear load characteristic over the operating load range.
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