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US4488706A Expired / Lapsed US ⏱️ 0.0 years remaining

Manhole cover lifting hook

Assignee: Individual
•
Filing: 1984-06-13
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Granted: 1984-12-18
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Expires: 2004-06-13
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Abstract

Abstract A hook for a manhole cover having a hook hole, comprises a lever rod having a load end, at least one roller rotatably mounted on the lever rod and rollingly movable at least in a back-and-forth direction, and a hook mounted on the load end for engaging in the hook hole in the manhole cover. The hook enables the worker to open and close a heavy manhole cover quite easily with a reduced expenditure of physical energy.

Inventors

  • 👤 Kazuhiko Kono

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 00:26
CPC Classifications
B; B66; B66F; B66F19/00; B66F19/005

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 230 words
A lifting device for lifting a manhole cover having a hook-receiving hole, comprising: an elongated lever rod having a load part at one end thereof and a handle on an opposite end thereof, said lever rod comprising an elongated bar having a shallow bend intermediate the ends thereof so that the bar has a shallow upwardly opening V-shaped configuration; a support member fixed to said bar in the vicinity of said bend and projecting downwardly therefrom, and a roller supported on said support member adjacent the lower end thereof; said load part of said rod having therein a substantially spherical cavity, said load part also having therein a narrow slot extending longitudinally of said lever rod and in communication with said cavity, said slot opening downwardly through the underside of said rod; and a hook swivelly and pivotally mounted on said load part and depending downwardly therefrom for engagement with the hook hole in the manhole cover; said hook including an elongated rodlike portion which projects downwardly through said slot and has a sidewardly projecting hook part fixed on the lower end thereof, said rodlike portion also having a ball-shaped portion fixed to the upper end thereof and rotatably retained in said spherical cavity for permitting the hook to both rotate about the longitudinal axis of the rodlike portion and vertically pivot along the longitudinal direction of the lever rod.
Claim 2
Dependent Claim 230 words
A lifting device for lifting a manhole cover having a hook-receiving hole, comprising: an elongated lever rod having a load part at one end thereof and a handle on an opposite end thereof, said lever rod comprising an elongated bar having a shallow bend intermediate the ends thereof so that the bar has a shallow upwardly opening V-shaped configuration; a support member fixed to said bar in the vicinity of said bend and projecting downwardly therefrom, and a roller supported on said support member adjacent the lower end thereof; said load part of said rod having therein a substantially spherical cavity, said load part also having therein a narrow slot extending longitudinally of said lever rod and in communication with said cavity, said slot opening downwardly through the underside of said rod; and a hook swivelly and pivotally mounted on said load part and depending downwardly therefrom for engagement with the hook hole in the manhole cover; said hook including an elongated rodlike portion which projects downwardly through said slot and has a sidewardly projecting hook part fixed on the lower end thereof, said rodlike portion also having a ball-shaped portion fixed to the upper end thereof and rotatably retained in said spherical cavity for permitting the hook to both rotate about the longitudinal axis of the rodlike portion and vertically pivot along the longitudinal direction of the lever rod.
Claim 3
Dependent Claim 16 words
A lifting device according to claim 1, wherein said hook part has an inverted T-shaped configuration.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-12-18 1988-06-18 1988-12-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-12-18 1992-06-18 1992-12-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-12-18 1996-06-18 1996-12-18 $7700.00 Window Closed / Lapsed

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