The spindle motor and the carriage assembly and storage medium drive

Clearance (58) is formed over the entire circumference of the annular body (37) between the spindle motor (15) in the annular body (37) and the stator (27). When the spindle motor (15) is immersed in pure water for example, towards the gap (58) the cylindrical space from (35) pure water enters. Clearance (58) gradually narrows as the distance from the cylindrical space (35) over the entire circumference of the annular body (37). As a result, balanced and the pressure and water pressure of the columnar space (35) over the entire circumference of the annular body (37). The surface tension of pure water between the outer end and an inner end of the gap (58) is generated. Pure water in the gap (58) thus establishing a meniscus shape. Entering of the pure water into the cylindrical space (35) is avoided. Cleaning of the outer surface of the spindle motor (15) after assembly of the spindle motor (15) is allowed. Dust from the outer surface is removed.