Abstract
Instead of conventional diaphragm controlled restrictors, a hydrostatically controlled restrict-or is designed for obtaining an infinite stiffness in a hydrostatic journal bearing. The journal bearing is constructed by inner and outer sleeves, and between these sleeves, a restrictor ring is inserted. An appropriate gap is formed between the inside of the ring and the inner sleeve. The pressurized oil is forced to pass through this gap, and restricted before it flows into pockets on the bearing surface to bear the load applied. The outside of the restrictor ring is supported elastically by an another hydrostatic journal bearing incorporated into the outer sleeve. The supporting stiffness of the ring can be controlled only by changing the oil supply pressure to the supporting bearing, and when the supporting stiffness (namely, the supply pressure) is opti- mized, the load applied to the main bearing can be borne without changing the oil film thickness on the main bearing surface ; thus the stiffness of the main bearing can be infinite. When the supply pressure to the supporting bearing is higher or lower than the optimum value, the stiffness of the main bearing can be positive or negative, respectively. Such an easy control of the bearing stiffness is very difficult for bearings with the conventional diaphragm controlled restrictors.
