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US4007940A Expired / Lapsed US ⏱️ 0.0 years remaining

Protected mechanical seal

Assignee: Individual
•
Filing: 1975-07-07
•
Granted: 1977-02-15
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Expires: 1995-07-07
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Abstract

Abstract An improvement in a mechanical seal assembly for a slurry pump, or like shaft rotating in a housing subject to incursions of grit contaminants of the type having relatively rotating first and second seal elements in annular engagement defining the seal, the first of the seal elements comprising telescopically interfitted inner and outer cylindrical members having seal-wear-responsive extensile movement to maintain sealing engagement with the second seal element, the grit contaminants tending to work between the first element inner and outer members and block their telescoping movement; the improvement comprising a rigid cylindrical shroud axially opposing and radially enclosing the first element concentrically for a substantial distance against grit contamination blocking inner and outer member telescoping movement.

Inventors

  • 👤 Roman Chapa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 20:15
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/16; F16J15/34; F16J15/38; F16K; F16K41/00; Y; Y10; Y10S; Y10S277/00; Y10S277/91

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 174 words
In a mechanical seal assembly for a slurry pump or like shaft rotating in a housing subject to incursions of grit contaminants, relatively rotating first and second seal elements in annular engagement defining the seal, the first of said seal elements comprising telescopically interfitted inner and outer cylindrical members having seal-wear-responsive extensile movement to maintain sealing engagement with said second seal element, said grit contaminants tending to work between said first element members and block their telescoping movement, the improvement of a third element comprising a rigid cylindrical shroud axially opposing and radially enclosing said first element concentrically, said shroud being cup-shaped having a relatively thick cross-section base and a relatively thin cross-section cylindrical wall, and means securing said first element inner member to said shaft for rotation therewith, and separate means securing said shroud to said shaft in inner member axially abutting relation free of radial engagement with said first element, to block grit contaminants from between said first element inner and outer members while commonly rotating with the shaft and first element.
Claim 2
Dependent Claim 174 words
In a mechanical seal assembly for a slurry pump or like shaft rotating in a housing subject to incursions of grit contaminants, relatively rotating first and second seal elements in annular engagement defining the seal, the first of said seal elements comprising telescopically interfitted inner and outer cylindrical members having seal-wear-responsive extensile movement to maintain sealing engagement with said second seal element, said grit contaminants tending to work between said first element members and block their telescoping movement, the improvement of a third element comprising a rigid cylindrical shroud axially opposing and radially enclosing said first element concentrically, said shroud being cup-shaped having a relatively thick cross-section base and a relatively thin cross-section cylindrical wall, and means securing said first element inner member to said shaft for rotation therewith, and separate means securing said shroud to said shaft in inner member axially abutting relation free of radial engagement with said first element, to block grit contaminants from between said first element inner and outer members while commonly rotating with the shaft and first element.
Claim 3
Dependent Claim 30 words
Mechanical seal assembly according to claim 1 in which said inner and outer first element members cooperatively define an annular space, and including also viscous fluid material filling said space.
Claim 4
Dependent Claim 24 words
Mechanical seal assembly according to claim 1 including also compression spring structure resiliently biasing said first seal element inner and outer members axially apart.
Claim 5
Dependent Claim 70 words
Mechanical seal assembly according to claim 1 in which said second seal element comprises a torus supported by said housing, said first seal element outer member carries a sealing surface in sealing engagement with said torus, and said first seal element inner member is secured to said shaft for rotation therewith and including also an O-ring seal in sealing engagement between said shaft and said first seal element inner member.
Claim 6
Dependent Claim 33 words
Mechanical seal assembly according to claim 1 including also compression spring structure between said first element inner and outer members resiliently maintaining said outer member in self-adjusting sealing engagement with said toroidal element.
Claim 7
Dependent Claim 24 words
Mechanical seal assembly according to claim 5 including also guide means between said inner and outer members guiding relative axial movement of said members.
Claim 8
Dependent Claim 45 words
Mechanical seal assembly according to claim 6 in which said outer member has circularly spaced slots, and said inner member has threaded fasteners defining means to secure the inner cylindrical member to said shaft, in registration with said outer cylindrical member slots for adjustment access.
Claim 9
Dependent Claim 21 words
Mechanical seal assembly according to claim 7 in which said shroud overlies said outer cylindrical member slots, in grit blocking relation.
Claim 10
Dependent Claim 20 words
Mechanical seal assembly according to claim 1 in which the thickness ratio of base to wall section is above 25.

References Cited (Backward Citations)

US2856210A Cited
US3420535A Cited
US3612548A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-02-15 1980-08-16 1981-02-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-02-15 1984-08-16 1985-02-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-02-15 1988-08-16 1989-02-15 $7700.00 Window Closed / Lapsed

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