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US3975870A Expired / Lapsed US ⏱️ 0.0 years remaining

Floor hatch

Assignee: Individual
•
Filing: 1974-09-05
•
Granted: 1976-08-24
•
Expires: 1994-09-05
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Abstract

Abstract A floor hatch including an outer framework adapted to be installed in a floor of a building and having an abutment face at the upper end of the inner surface of the framework and a cover assembly fitted in the outer framework, said cover assembly including an inner framework having an abutment face at the upper end of the outer surface of the inner framework for abutting against the abutment face on the outer framework and a cover member attached to the inner framework for closing the opening in the inner framework, whereby the cover assembly is fitted and supported in the outer framework.

Inventors

  • 👤 Hiromitsu Naka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 16:01
CPC Classifications
E; E02; E02D; E02D29/00; E02D29/12; E02D29/14

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 346 words
A floor hatch comprising: a quadrilateral outer framework adapted to be installed in a building floor and having an abutment face at the upper end of the inner surface of said outer framework; and a cover assembly fitted in said outer framework, said cover assembly including: a quadrilateral inner framework for supporting said cover assembly in said outer framework and having an abutment face on the outer surface of said inner framework for sealingly engaging against said abutment face of said outer framework; said inner framework having four elongated inner framework members and corner members connecting said framework members together and screws joining said framework members and said corner members; an upper end flange around the inside of said inner framework adjacent the upper edge of said inner framework; an intermediate flange around the inside of said inner framework intermediate the upper and lower edges of said inner framework; a lower end flange around the inside of said inner framework adjacent the lower edge of said inner framework; said flanges extending horizontally inwardly from said inner framework and a cover member engaged between a pair of adjacent flanges and fixed in said inner framework between said adjacent flanges for closing the opening in the inner framework; each of said flanges being spaced from an adjacent flange a distance substantially equal to the thickness of the edge of said cover member, whereby the cover member is held in the inner framework between a pair of adjacent flanges without the necessity of any fastening means and when the cover member is between the upper and intermediate flanges, the upper surface of the cover member is substantially flush with the floor around the outer framework so that a floor covering can be placed on the floor hatch, and when the cover member is between the intermediate and lower flanges there is a space between the cover member and the top edges of the inner and outer frameworks which can be filled with concrete or the like for providing a surface level with the floor surface around the floor hatch.
Claim 2
Dependent Claim 346 words
A floor hatch comprising: a quadrilateral outer framework adapted to be installed in a building floor and having an abutment face at the upper end of the inner surface of said outer framework; and a cover assembly fitted in said outer framework, said cover assembly including: a quadrilateral inner framework for supporting said cover assembly in said outer framework and having an abutment face on the outer surface of said inner framework for sealingly engaging against said abutment face of said outer framework; said inner framework having four elongated inner framework members and corner members connecting said framework members together and screws joining said framework members and said corner members; an upper end flange around the inside of said inner framework adjacent the upper edge of said inner framework; an intermediate flange around the inside of said inner framework intermediate the upper and lower edges of said inner framework; a lower end flange around the inside of said inner framework adjacent the lower edge of said inner framework; said flanges extending horizontally inwardly from said inner framework and a cover member engaged between a pair of adjacent flanges and fixed in said inner framework between said adjacent flanges for closing the opening in the inner framework; each of said flanges being spaced from an adjacent flange a distance substantially equal to the thickness of the edge of said cover member, whereby the cover member is held in the inner framework between a pair of adjacent flanges without the necessity of any fastening means and when the cover member is between the upper and intermediate flanges, the upper surface of the cover member is substantially flush with the floor around the outer framework so that a floor covering can be placed on the floor hatch, and when the cover member is between the intermediate and lower flanges there is a space between the cover member and the top edges of the inner and outer frameworks which can be filled with concrete or the like for providing a surface level with the floor surface around the floor hatch.
Claim 3
Dependent Claim 27 words
A floor hatch as claimed in claim 1 in which said cover member is held in said inner framework between said intermediate and said upper end flanges.
Claim 4
Dependent Claim 26 words
A floor hatch as claimed in claim 1 in which said cover member is held in said inner framework between said intermediate and lower end flanges.
Claim 5
Dependent Claim 26 words
The floor hatch according to claim 1, in which said cover member comprises a plurality of cover elements and connectors connecting said cover element in succession.
Claim 6
Dependent Claim 21 words
The floor hatch according to claim 1, further comprising sealing means between the lower ends of said outer and inner frameworks.

References Cited (Backward Citations)

GB190619077A Cited
US1027911A Cited
GB203369A Cited
GB217789A Cited
US1600761A Cited
GB318012A Cited
US2109287A Cited
US2194221A Cited
NL6413948A Cited
US3408778A Cited
US3712009A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-08-24 1980-02-23 1980-08-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-08-24 1984-02-23 1984-08-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-08-24 1988-02-23 1988-08-24 $7700.00 Window Closed / Lapsed

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