US4203686A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manhole construction
Assignee: Individual
•
Filing: 1978-07-17
•
Granted: 1980-05-20
•
Expires: 1998-07-17
Abstract
Abstract A liquid-tight manhole closure structure including a base frame having a manhole opening therein, a manhole cover for placement in the manhole opening, and a retainer ring for detachably securing the cover on the frame. The retainer ring and frame having peripheral coacting, detachably interlocking, cam surfaces for removably securing the ring to the frame. A resilient sealant is disposed between the cover and the frame to prevent liquid seepage through the manhole opening. The sealant may be vulcanized or otherwise secured directly to the periphery of the cover and/or to the frame.
Inventors
- 👤 Harold M. Bowman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:50
CPC Classifications
E; E02; E02D; E02D29/00; E02D29/12; E02D29/14; Y; Y10; Y10S; Y10S285/00; Y10S285/901
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
97 words
In a manhole cover assembly including a base frame defining a manhole opening and having a peripheral annular inner seat for receiving a manhole cover, an annular manhole cover seated on said seat, an annular retainer ring coacting with said cover and said frame for holding said cover in place on said seat, whereby said cover and said ring coact to present a substantially common flush surface with the top of said base frame, said retainer ring including means coacting with means on said frame for removably securing said retainer ring and said cover to said frame.
Claim 2
Dependent Claim
97 words
In a manhole cover assembly including a base frame defining a manhole opening and having a peripheral annular inner seat for receiving a manhole cover, an annular manhole cover seated on said seat, an annular retainer ring coacting with said cover and said frame for holding said cover in place on said seat, whereby said cover and said ring coact to present a substantially common flush surface with the top of said base frame, said retainer ring including means coacting with means on said frame for removably securing said retainer ring and said cover to said frame.
Claim 3
Dependent Claim
29 words
An assembly in accordance with claim 1 including sealing means coacting between said cover and said seat for sealing the manhole opening in said frame against ingress of water.
Claim 4
Dependent Claim
26 words
An assembly in accordance with claim 1 including means in said retainer ring for facilitating the orientation thereof into locking condition with respect to said frame.
Claim 5
Dependent Claim
38 words
A manhole cover in accordance with claim 3 wherein said last mentioned means comprises slot means in said retainer ring adapted for receiving an associated tool for causing rotation of the retainer ring with respect to said frame.
Claim 6
Dependent Claim
79 words
An assembly in accordance with claim 1 wherein said face frame comprises an upwardly sloping outwardly oblique surface adjacent said seat defining a shoulder adapted for restricting horizontal movement of said manhole cover, a generally horizontal surface disposed above said shoulder and adjacent thereto adapted for seating said retainer ring, and cam means disposed above the last mentioned seat adapted for camming coaction with cam means on said retainer ring for locking the retainer ring to said base frame.
Claim 7
Dependent Claim
101 words
An assembly in accordance with claim 2 wherein said retainer ring includes laterally projecting ring lugs spaced about the exterior periphery thereof, said ring lugs having ring cam surfaces thereon, said base frame having inwardly projecting spaced frame lugs formed around the inner upper periphery of the frame, said frame lugs having frame cam surfaces facing downwardly of the frame, said ring cam surfaces being adapted for camming coaction with the complementary frame cam surfaces on said base frame for locking said retainer ring to said base frame and thus locking said manhole cover on the seat of said base frame.
Claim 8
Dependent Claim
47 words
An assembly in accordance with claim 1 including recess means in said base frame disposed laterally outwardly of said manhole cover seat surface adapted for receiving liquid seepage between the juncture of said retainer ring and said manhole cover draining the liquid laterally of said base frame.
Claim 9
Dependent Claim
30 words
A manhole cover in accordance with claim 1 including sealing means vulcanized to the manhole cover seat and adapted to seal the manhole cover with respect to the base frame.
Claim 10
Dependent Claim
27 words
An assembly in accordance with claim 2 wherein said sealing means is secured to said base frame and covers at least a part of said seat surface.
Claim 11
Dependent Claim
28 words
An assembly in accordance with claim 1 wherein said sealing means is secured to said manhole cover and covers at least a part of said manhole cover seat.
References Cited (Backward Citations)
US1580541A
Cited
US2328068A
Cited
US2661863A
Cited
US2879914A
Cited
US3920347A
Cited
US4032036A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-05-20 | 1983-11-19 | 1984-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-05-20 | 1987-11-19 | 1988-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-05-20 | 1991-11-19 | 1992-05-20 | $7700.00 | Window Closed / Lapsed |