DYNAMIC PRESSURE TYPE GAS BEARING DEVICE

摘要

PURPOSE:To keep the steady rotation of a shaft body against external force by providing a communicating hole formed so as to communicate from the maximum pressure part of a herringbone groove to a part not to abut on an end cover on the side of the free end of the shaft body with a pressure throttling part having a diameter smaller than that of the communicating hole, and the above cover with a pressure regulating hole. CONSTITUTION:The maximum pressure part of a herringbone-shaped dynamic pressure generating groove 2A provided on the outer periphery of a shaft body 2 having a fixed lower end part is provided with a peripheral groove 2B, and a communicating hole 2C is drilledly provided from the peripheral groove 2B to the upper end face of the shaft body 2, and a pressure throttling hole 8 is provided at a part of the hole 2C. A cover 7 with a pressure regulating hole 7A is fixed opposite to the end face of the shaft body 2 of a rotatable sleeve 3. Thus the pressure regulating hole 7A is opened and closed against external strong vibration for the hardly changeable pressure of a radial bearing to keep the steady rotation of the shaft body.