Patent attributes
An oil seal structure of a supercharger (10) has an oil shield member (21), a seal housing (25), and an annular seal member (23) arranged between the oil shield member (21) and the seal housing (25). The oil shield member (21) has a portion in which an approximately circular outer edge is formed in a vertical cross section to an axial direction, in a leading end portion in a compressor side, and the oil shield member (21) has an outer edge reduced-diameter portion (21a) which is formed in the leading end in the compressor side and in which a radius of the outer edge is smaller than the other portions of the outer edge. The seal member (23) is fitted to the outer edge reduced-diameter portion (21a). An opening through which the oil shield member (21) passes is formed in the seal housing (25), and the seal housing (25) is brought into contact with the seal member (23) in an inner edge in a radial direction forming the opening.