Application of electrorheological fluid dampers to machine tool elements

Electrorheological fluids (ERF) are colloidal suspension whose apparent viscosity is variable in response to the strength of an electric field. In this paper, the application of electrorheological fluids to machine tool elements is proposed. The dynamic characteristics of machine tool table systems with linear motion rolling element bearings are improved by using an ERF film damper. A high damping force can be induced by increasing the ERF viscosity when the table is being moved during machining and the viscosity can be reduced when the table is being moved rapidly so providing less viscous drag. The performance of the hydrostatic bearing can be controlled by using ERF instead of hydraulic oil. The bearing clearance and load carrying capacity can be controlled by adjusting the intensity of the applied electric field.