Rotating device and manufacturing method thereof

A method for manufacturing a rotating device, the rotating device comprising:

• a shaft body comprising a lower rod, a lower flange extending outwardly in a radial direction from a side face of the lower rod at one end side, an upper rod formed with a retainer hole encircling a part of the lower rod and fixing the lower rod, and an upper flange extending outwardly in the radial direction from a side face of the upper rod at a side distant from the lower flange in an axial direction;
• a bearing body comprising a shaft encircling member which is present in a space between the lower flange and the upper flange in the axial direction, encircles the shaft body, and is freely rotatable relative to the shaft body;
• a radial dynamic pressure generating groove which is provided in either one of the shaft body and the bearing body and which generates dynamic pressure in the radial direction;
• a thrust dynamic pressure generating groove which is provided in either one of the shaft body and the bearing body and which generates dynamic pressure in a thrust direction;
• and
• a lubrication medium present in a gap between the shaft body and the bearing body,
• the method comprising:
• inspecting a dimension of a play of the shaft encircling member between the upper flange and the lower flange in the axial direction with the shaft encircling member being placed between the upper flange fixed to the upper rod and the lower flange fixed to the lower rod, and the lower rod being inserted in the retainer hole of the upper rod up to a predetermined insertion position;
• changing the insertion position of the lower rod in the retainer hole of the upper rod in accordance with a desired dimension of a play of the shaft encircling member in the axial direction between the upper flange and the lower flange and the inspected dimension of the play in the axial direction;
• and
• fixing the lower rod to the upper rod with the insertion position of the lower rod in the retainer hole being changed.

A method for manufacturing a rotating device, the rotating device comprising:

• a shaft body comprising a lower rod, a lower flange extending outwardly in a radial direction from a side face of the lower rod at one end side, an upper rod formed with a retainer hole encircling a part of the lower rod and fixing the lower rod, and an upper flange extending outwardly in the radial direction from a side face of the upper rod at a side distant from the lower flange in an axial direction;
• a bearing body comprising a shaft encircling member which is present in a space between the lower flange and the upper flange in the axial direction, encircles the shaft body, and is freely rotatable relative to the shaft body;
• a radial dynamic pressure generating groove which is provided in either one of the shaft body and the bearing body and which generates dynamic pressure in the radial direction;
• a thrust dynamic pressure generating groove which is provided in either one of the shaft body and the bearing body and which generates dynamic pressure in a thrust direction;
• and
• a lubrication medium present in a gap between the shaft body and the bearing body,
• the upper flange comprising a tapered face which is provided at an outer periphery side face, increases a diameter toward the lower flange, and contacts an air-liquid interface of the lubrication medium,
• a sloped portion being provided at an end face of the upper flange opposite to the lower flange and inclining from an outer periphery side to an inner periphery side toward the lower flange,
• the method comprising:
• inspecting a position of the sloped portion by emitting laser light to the sloped portion;
• and
• inspecting a position of the air-liquid interface by emitting laser light to the air-liquid interface.