PURPOSE: To maintain a shaft in an optimum rigidity in accordance with various conditions by providing a nozzle with an electrostrictive element by which the sectional area of the nozzle hole can be changed, and by controlling the electrostrictive element so that the shaft can maintain a prescribed rigidity.
CONSTITUTION: A nozzle 7 which has been provided at the downstream end of an oil supply passage 6 is fixed to a bearing metal 2, and an electrostrictive element 8 by which the part situated in the inside of the nozzle hole 7a is expanded or contracted by the change of voltage so as to change the sectional area is held in the nozzle 7. Further, a temperature sensor 9 is provided in the bearing metal 2, and the signal thereof is input into a controller 10, whose output is introduced to the electrostrictive element 8 via an amplifier 11, so that the supply quantity of lubricating oil can be controlled by the memory, provided in the controller 10, with regard to the relationship between the temperature of bearing pockets 4 and the quantity of lubricating oil. Thus, the rigidity of a shaft can be maintained in an optimum value in accordance with various conditions.
SAKAKIBARA NORIO
HORI NOBUMITSU
YAMAKAWA YOICHI
