Cassette seal

A cassette seal for sealing an annular gap between a shaft having a longitudinal axis and mounted for rotation about its longitudinal axis and a surface defining an aperture in a housing through which the shaft projects and for separating an internal volume of the housing at an axially inner end of the cassette seal from atmosphere at an axially outer end of the cassette seal, the cassette seal comprising:

• an annular rotational member for mounting rotationally fast with the shaft;
• and
• an annular stationary member for mounting to the surface of the housing defining the aperture;
• wherein the stationary member comprises a sealing element for forming a static oil seal with the surface of the housing;
• wherein the stationary member encircles at least part of the rotational member and has a sealing lip configured to resiliently engage a sealing surface on the rotational member to form an oil seal between the stationary and rotational members;
• wherein the stationary member has a radially extending portion located axially outboard of the at least one secondary sealing lip, wherein the radially extending portion of the stationary member extends radially outward such that in use, the radially extending portion of the stationary member locates adjacent an outer surface of the housing extending radially about the aperture;
• wherein the rotational member comprises a second reinforcing member having a first axially extending cylindrical region for location adjacent the shaft and carrying a first elastomeric sealing member for forming a static oil seal with the shaft,
• wherein the second reinforcing member has a first radially extending region extending radially outward at an axial outer end of the first axially extending cylindrical region, a second axially extending cylindrical region extending axially outward from a radially outer end of the first radially extending region, and a second radially extending region extending radially outward at an axially outer end of the second axially extending region;
• wherein the rotational member has a further elastomeric sealing member attached to the second axially extending cylindrical region;
• and
• wherein the further elastomeric member comprises:
• at least one secondary sealing lip configured to engage a sealing surface of the stationary member at a position axially outboard of the oil sealing lip;
• and
• at least one exterior sealing lip extending radially outward and axially inward to engage an outer surface of the radially extending portion of the stationary member.