Abstract: A vibration damping rubber bushing including: an inner cylindrical member; a main rubber elastic body bonded to an outer circumferential face of the inner cylindrical member; a plurality of anti-slip projections provided on at least one of axial end faces of the inner cylindrical member that project axially outward from the axial end face and extend with ribbed shape in a diametrical direction on the axial end face to produce a spokewise pattern overall; and an annular water barrier projection provided on a diametrical medial section of the at least one of the axial end faces of the inner cylindrical member, projecting axially outwardly and extending circumferentially, with the anti-slip projections being disposed to both radially inner side and radially outer side of the annular water barrier projection.

Abstract: A method of manufacturing a cylindrical member having anti-slip projections formed on axial end faces, the method comprising the steps of: employing a roller die, which is provided with a circumferential die groove of annular form extending through a medial section in a generatrix direction of a die face defined by an integral tapered outside peripheral face, and with a plurality of sloping die grooves extending in a tapered slope direction of the die face situated to both large-diameter and small-diameter sides of the circumferential die groove; providing plastic working to the axial end face with the small-diameter side of the roller die facing towards an inner peripheral side of the cylindrical member and with the large-diameter side facing towards an outer peripheral side, by pushing the die face against the axial end face while rotating circumferentially; and forming simultaneously an annular water barrier projection and the anti-slip projections.

Abstract: A method of manufacturing a cylindrical member having anti-slip projections formed on axial end faces, the method comprising the steps of: employing a roller die, which is provided with a circumferential die groove of annular form extending through a medial section in a generatrix direction of a die face defined by an integral tapered outside peripheral face, and with a plurality of sloping die grooves extending in a tapered slope direction of the die face situated to both large-diameter and small-diameter sides of the circumferential die groove; providing plastic working to the axial end face with the small-diameter side of the roller die facing towards an inner peripheral side of the cylindrical member and with the large-diameter side facing towards an outer peripheral side, by pushing the die face against the axial end face while rotating circumferentially; and forming simultaneously an annular water barrier projection and the anti-slip projections.

Abstract: A vibration damping rubber bushing including: an inner cylindrical member; a main rubber elastic body bonded to an outer circumferential face of the inner cylindrical member; a plurality of anti-slip projections provided on at least one of axial end faces of the inner cylindrical member that project axially outward from the axial end face and extend with ribbed shape in a diametrical direction on the axial end face to produce a spokewise pattern overall; and an annular water barrier projection provided on a diametrical medial section of the at least one of the axial end faces of the inner cylindrical member, projecting axially outwardly and extending circumferentially, with the anti-slip projections being disposed to both radially inner side and radially outer side of the annular water barrier projection.