The present invention provides a seal housing ( 102 ) for releasable attachment to a hydraulic or pneumatic cylinder ( 101 ), the seal housing ( 102 ) being suitable for retaining a seal assembly and the seal housing ( 102 ) comprising a generally annular main body ( 201 ). The annular main body ( 201 ) defines an annular disc-shaped portion ( 202 ) having an upper surface ( 203 ), a lower surface ( 204 ), an outer peripheral edge ( 205 ) and an inner edge ( 206 ). Said inner edge ( 206 ) bounds a circular opening ( 207 ) extending the full height of said annular disc shaped portion ( 202 ) between said upper and lower surfaces ( 203, 204 ). The annular main body ( 201 ) further defines an annular collar portion ( 208 ) upstanding from the upper surface ( 203 ) of said disc shaped portion ( 202 ) adjacent said peripheral edge ( 205 ) of said disc shaped portion ( 202 ), said annular collar portion ( 208 ) extending height-wise from a base end ( 209 ) joined to said disc-shaped portion ( 202 ) to an upper end ( 210 ), and width-wise from an inner edge ( 211 ) to an outer peripheral edge ( 212 ), said inner edge ( 211 ) of said annular collar portion ( 208 ) bounding a circular opening ( 213 ) extending the full height of said annular collar portion ( 208 ). The annular main body ( 201 ) also further defines an annular flange portion ( 216 ) extending height-wise downwardly from the lower surface ( 204 ) of said disc-shaped portion ( 202 ) from a base end ( 217 ) joined to said lower surface ( 204 ) of said disc-shaped portion ( 202 ) to a distal end ( 218 ), and width wise from an inner edge ( 219 ) to an outer edge ( 220 ).
1. A seal housing for releasable attachment to a hydraulic or pneumatic cylinder pre-sealed by a sealing assembly, the seal housing being suitable for retaining a seal assembly auxiliary to said sealing assembly of said hydraulic or pneumatic cylinder and the seal housing comprising a generally annular main body, the annular main body defining:
an annular disc-shaped portion having an upper surface, a lower surface, an outer peripheral edge and an inner edge, said inner edge bounding a circular opening extending the full height of said annular disc shaped portion between said upper and lower surfaces;
an annular collar portion upstanding from the upper surface of said disc shaped portion adjacent said peripheral edge of said disc shaped portion, said annular collar portion extending height-wise from a base end joined to said disc-shaped portion to an upper end, and width-wise from an inner edge to an outer peripheral edge, said inner edge of said annular collar portion bounding a circular opening extending the full height of said annular collar portion; and
an annular flange portion extending height-wise downwardly from the lower surface of said disc-shaped portion from a base end joined to said lower surface of said disc-shaped portion to a distal end, and width wise from an inner edge to an outer edge; and wherein said annular flange portion is resiliently flexible relative to said annular disc-shaped portion generally about its base end.
2. The seal housing of claim 1 , in which the diameter of said circular opening defined by said annular collar portion is greater than the diameter of said circular opening defined by said annular disc-shaped portion.
3. The seal housing of claim 1 , in which said annular disc-shaped portion, said annular collar portion, and said annular flange portion have a unitary construction.
4. The seal housing of claim 1 , in which said annular disc-shaped portion, said annular collar portion, and said annular flange portion are defined by a unitary moulding.
5. The seal housing of claim 1 , in which said annular disc-shaped portion, said annular collar portion, and said annular flange portion are formed of a Polyoxymethylene (POM) thermoplastics material.
6. The seal housing of claim 1 , in which said main body is suitable for retaining an annular seal assembly within the volume bounded by the plane of the upper surface of the annular disc-shaped portion, the inner edge of the annular collar portion, and a plane aligned with the upper end of said annular collar portion.
7. The seal housing of claim 1 , further comprising an annular seal assembly retained within the volume bounded by the plane of the upper surface of the annular disc-shaped portion, the inner edge of the annular collar portion, and a plane aligned with the upper end of said annular collar portion.
8. The seal housing of claim 7 , in which said annular seal assembly is retained in place by means of an interference fit between an exterior surface of the annular seal assembly and said inner edge of said annular collar portion.
9. The seal housing of claim 7 , in which said annular seal assembly comprises a scraper seal defining a sealing lip adapted to scrape contaminants from the surface of the piston of a pneumatic or hydraulic cylinder to which the seal housing may be attached.
10. The seal housing of claim 1 , adapted for releasable attachment to a hydraulic or pneumatic cylinder comprising a cylindrical housing defining internally a chamber for receiving a working fluid and defining a circular opening through one end face of the housing, and further comprising a piston axially reciprocable within the housing through the opening; in which said seal housing is configured for attachment to said end face of said housing coaxially with said circular opening; and in which said seal housing is configured for retaining an annular seal assembly comprising a sealing lip in contact with said piston.
11. A hydraulic or pneumatic cylinder comprising:
a cylindrical housing defining internally a chamber for receiving a working fluid and defining a circular opening through one end face of the housing;
a piston axially reciprocable within the housing through the opening;
a sealing assembly installed in the housing opening annular about the piston arranged to provide a substantially fluid tight seal between the piston and the housing; and
a seal housing releasably attached to said end face of said housing, said seal housing retaining an annular seal assembly comprising an annular sealing lip in contact with said piston, said annular seal assembly being auxiliary to said sealing assembly;
in which the seal housing comprises a generally annular main body, the annular main body defining:
an annular disc-shaped portion having an upper surface, a lower surface, an outer peripheral edge and an inner edge, said inner edge bounding a circular opening extending the full height of said annular disc shaped portion between said upper and lower surfaces;
an annular collar portion upstanding from the upper surface of said disc shaped portion adjacent said peripheral edge of said disc shaped portion, said annular collar portion extending height-wise from a base end joined to said disc-shaped portion to an upper end, and width-wise from an inner edge to an outer peripheral edge, said inner edge of said annular collar portion bounding a circular opening extending the full height of said annular collar portion; and
an annular flange portion extending height-wise downwardly from the lower surface of said disc-shaped portion from a base end joined to said lower surface of said disc-shaped portion to a distal end, and width wise from an inner edge to an outer edge; and wherein said annular flange portion is resiliently flexible relative to said annular disc-shaped portion generally about its base end.
12. A seal housing for releasable attachment to a hydraulic or pneumatic cylinder pre-sealed by a sealing assembly, the seal housing being suitable for retaining a seal assembly auxiliary to said sealing assembly of said hydraulic or pneumatic cylinder and the seal housing comprising a generally annular main body, the annular main body defining:
an annular disc-shaped portion having an upper surface, a lower surface, an outer peripheral edge and an inner edge, said inner edge bounding a circular opening extending the full height of said annular disc shaped portion between said upper and lower surfaces;
an annular collar portion upstanding from the upper surface of said disc shaped portion adjacent said peripheral edge of said disc shaped portion, said annular collar portion extending height-wise from a base end joined to said disc-shaped portion to an upper end, and width-wise from an inner edge to an outer peripheral edge, said inner edge of said annular collar portion bounding a circular opening extending the full height of said annular collar portion; and
an annular flange portion extending height-wise downwardly from the lower surface of said disc-shaped portion from a base end joined to said disc-shaped portion to a distal end, and width wise from an inner edge to an outer edge, said inner edge of said annular flange portion bounding a circular opening extending the full height of said annular flange portion, the diameter of said opening defined by said flange portion being greater than the diameter of said opening defined by said annular disc-shaped portion;
in which a first annular region of said lower surface of said annular disc-shaped portion extends in a first plane defining a height-wise lowermost extent of said lower surface of said disc-shaped portion, and in which said lower surface of said annular disc-shaped portion is concaved inwardly of said annular disc-shaped portion away from said first plane at a second annular region, said second annular region being directly adjacent and surrounding said circular opening and extending radially outwards towards the region at which said annular flange portion is joined to said annular disc-shaped portion.
13. The seal housing of claim 12 , in which said first and second annular regions of said lower surface of said annular disc-shaped portion are approximately concentric and centred on the centre of said opening of said annular disc shaped portion, said first annular region have a greater radius than said second annular region, and said first annular region extending radially outwards of said second annular region towards said outer peripheral edge of said annular disc-shaped portion.
14. The seal housing of claim 12 , further comprising an annular seal assembly retained within the volume bounded by the plane of the upper surface of the annular disc-shaped portion, the inner edge of the annular collar portion, and a plane aligned with the upper end of said annular collar portion.
15. The seal housing of claim 14 , in which said annular seal assembly is retained in place by means of an interference fit between an exterior surface of the annular seal assembly and said inner edge of said annular collar portion.
16. The seal housing of claim 14 , in which said annular seal assembly comprises a scraper seal defining a sealing lip adapted to scrape contaminants from a surface of a piston of a pneumatic or hydraulic cylinder to which the seal housing may be attached.
17. The seal housing of claim 12 , adapted for releasable attachment to a hydraulic or pneumatic cylinder comprising a cylindrical housing defining internally a chamber for receiving a working fluid and defining a circular opening through one end face of the housing, and further comprising a piston axially reciprocable within the housing through the opening; in which said seal housing is configured for attachment to said end face of said housing coaxially with said circular opening; and in which said seal housing is configured for retaining an annular seal assembly in sealing contact with said piston.