Device for Supplying the Hydrostatic Pockets with Compensation of the Fluid Temperature

Abstract

The supply devices of the hydrostatic guideway pockets are elements with a major influence on the rigidity of the machine tool guideways. The value of the flow that circulates through these devices depends on the fluid viscosity as well. The researches in this field show that an important increase of the fluid temperature is produced when it passes through various orifices, slits and interstices that belong to the hydrostatic systems. The increase of the working temperature leads to decreasing the kinematic viscosity, with undesirable effects on the functioning of the hydrostatic guideways. In order to minimize this disadvantage, this work is presenting a constructive solution of a fixed supply device (flow control valve) with fluid temperature compensation. This type of device avoids the negative effects of increased fluid viscosity caused by the temperature increase as well, by automatically modifying the flowing cross section that is performed through a compensation bushing. The constructive solution of the new supply device is simple and involves relative low workmanship and costs. This supply device has been experimented on a rotary table model MRD 1500x2000, on the linear axis of 2200 mm travel. Through the comparative analyses of the new solution versus the standard one that was using as supply device a capillary type resistor, an increase of the guideway rigidity by 13% has resulted.