Patent ID: 8608384
Filing Date: 2013-12-17
Classification: F16C,G11B

Abstract:
1. A rotating device comprising: a fixing body including a shaft with a first end and a second end, and a shaft holder fixing the first end of the shaft; a rotating body including a shaft encircling member and a middle encircling member, the shaft encircling member including a cylinder part encircling the shaft, and a disk part extending from an end of the cylinder part at a side of the shaft holder in a radial direction vertical to a rotational axis of the rotating body and having an outer periphery protruding outwardly of the cylinder part in the radial direction, and the middle encircling member including an inner periphery encircling the cylinder part, and an end face facing an end face of the disk part in a direction of the rotational axis via a clearance; a radial dynamic pressure generating groove disposed in either one of a surface of the cylinder part and a surface of the shaft facing with each other in the radial direction; a thrust dynamic pressure generating groove disposed in either one of a surface of the disk part and a surface of the shaft holder facing with each other in the rotational axis direction; a lubricant continuously present from a first air-liquid interface to a second air-liquid interface at least between the rotating body and the fixing body; an encircling member fixed to the shaft holder while encircling the middle encircling member, and having an inner periphery where the first air-liquid interface of the lubricant contacts; a passage filled with the lubricant, passing through the thrust dynamic pressure generating groove and the radial dynamic pressure generating groove, and reaching the second air-liquid interface from the first air-liquid interface; and a communicating passage including a rotational-axis-direction passage provided in at least one of the middle encircling member and the shaft encircling member, and a radial-direction passage provided in the clearance where the disk part and the middle encircling member face with each other in the rotational axis direction, being filled with the lubricant, and reaching the second air-liquid interface from the first air-liquid interface without passing through the thrust dynamic pressure generating groove and the radial dynamic pressure generating groove, wherein an outward opening of the radial-direction passage is provided at a location overlapping the radial dynamic pressure generating groove in the rotational axis direction.