Patent US1980586A successfully refreshed from Google Patents.
US3846031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceiling grid system expansion joint
Assignee: Rollform Inc
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Filing: 1972-04-04
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Granted: 1974-11-05
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Expires: 1992-04-04
Abstract
Abstract A structural main beam for use in the supporting lattice or grid of a fire rated suspended ceiling comprising a longitudinally extending web having bulb and flange portions located along opposite upper and lower marginal edges thereof, and including coupling means at opposite longitudinal ends for expandably interlocking a pair of beams in end to end relationship. Thermal expansion of the beam is localized in the interlocking coupling means and in at least one deformable section formed by a pair of vertically oriented apertures or cut outs in the web, the apertures being disposed proximate each of the bulb and flange portions respectively to permit bending thereof whereby the integrity of the ceiling is substantially maintained when subjected to extremely high thermal stresses such as can occur during exposure to a fire.
Inventors
- 👤 G Adams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 02:03
CPC Classifications
E; E04; E04B; E04B9/00; E04B9/06; E04B9/065; E04B9/067; E04B9/068; E04B9/08; E04B9/12; E04B9/122; Y; Y10; Y10S; Y10S52/00; Y10S52/05; Y10T; Y10T403/00; Y10T403/21; Y10T403/49; Y10T403/4991
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
170 words
A controlled expansion beam for use in a ceiling grid system comprising: a longitudinally elongated web having a lower flange adapted to support the marginal edge portion of a ceiling panel and an upper continuous bulb portion; and means formed in said web intermediate the ends of said beam providing a controlled localized expansion relief section for said beam, said means including upper and lower longitudinally elongated apertures formed solely in said web one above the other and disposed in spaced relationship between said flange and said bulb portion, said apertures defining longitudinally extending upper and lower continuous marginal strips in the web along and adjacent to said bulb portion and said flange, said marginal strip located adjacent to said flange being of substantially uniform width and provided intermediate the ends thereof with only a single medianly disposed notch means which extends downwardly from said lower aperture and terminates short of said flange for controlled downward buckling of said flange in response to longitudinal compressive forces applied to said beam.
Claim 2
Dependent Claim
170 words
A controlled expansion beam for use in a ceiling grid system comprising: a longitudinally elongated web having a lower flange adapted to support the marginal edge portion of a ceiling panel and an upper continuous bulb portion; and means formed in said web intermediate the ends of said beam providing a controlled localized expansion relief section for said beam, said means including upper and lower longitudinally elongated apertures formed solely in said web one above the other and disposed in spaced relationship between said flange and said bulb portion, said apertures defining longitudinally extending upper and lower continuous marginal strips in the web along and adjacent to said bulb portion and said flange, said marginal strip located adjacent to said flange being of substantially uniform width and provided intermediate the ends thereof with only a single medianly disposed notch means which extends downwardly from said lower aperture and terminates short of said flange for controlled downward buckling of said flange in response to longitudinal compressive forces applied to said beam.
Claim 3
Dependent Claim
32 words
The beam as recited in claim 1 wherein said bulb includes a plurality of creases proximate said upper aperture to facilitate lateral deflection of said bulb when said beam is compressed longitudinally.
Claim 4
Dependent Claim
44 words
The beam as recited in claim 1 wherein said upper and lower apertures further define a relatively thin strip in said web between said apertures and said upper and lower marginal strips which is adapted to deflect laterally under longiTudinal compression of said beam.
Claim 5
Dependent Claim
21 words
The beam as recited in claim 1 wherein a controlled localized expansion section is provided adjacent each end of said beam.
Claim 6
Dependent Claim
19 words
The beam as recited in claim 1 wherein the upper of said apertures is longer than said lower aperture.
Claim 7
Dependent Claim
34 words
The beam as recited in claim 1 including means located proximate, at least, one end of said beam for interlockingly connecting said beam in end to end relationship with a beam of similar configuration.
Claim 8
Dependent Claim
30 words
The beam as recited in claim 6 wherein said means includes a tab projecting outwardly from said web, and an aperture located inwardly in said web relative to said tab.
Claim 9
Dependent Claim
72 words
The beam as set forth in claim 1 wherein said bulb portion is cut back at an end of said beam and including means at said end of said beam for connecting the latter in endwise butting relation to another similar beam, said means adapted to permit the interconnected ends of said beams to slide toward each other within limits defined at least in part by the cut-back of said bulb portion.
Claim 10
Dependent Claim
108 words
The beam as set forth in claim 8 wherein said means comprises a generally rectangular aperture adjacent to the mentioned end of said beam, and a longitudinal tongue on said end laterally offset from the plane of the web of said beam, said tongue adapted to extend alongside the web of said other similar beam and to be folded back through a similar aperture in said other beam, said tongue adapted further to slide longitudinally in said aperture and fitting snugly between the upper and lower edges thereof normally and during sliding movement thereof to hold said beam and said other beam substantially in alignment with each other.
Claim 11
Dependent Claim
131 words
A controlled expansion beam as recited in claim 1 further including a second beam substantially similar to the first recited beam and disposed in endwise butting relation with said first recited beam; and means providing a sliding interlocking connection between said beams, said means holding the butted ends of said beams rigidly together and in alignment with each other while permitting said ends to crush together when said beams are compressed longitudinally as under thermal expansion, the bulb portions of both beams being cut back and spaced apart at the butted ends of the beams to facilitate crushing together of said beams and the cutback ends of said bulb portions adapted to interengage to limit the extent to which said beams can crush together to relieve compressive forces in said beams.
Claim 12
Dependent Claim
79 words
A pair of controlled expansion beams as set forth in claim 10 wherein each of said beams is provided adjacent each end thereof with an expansion relief section of the type specified in claim 1, said expansion relief sections and the cut-backs in the bulb portions of said beams being mutually collectively operable to absorb and relieve forces of longitudinal compression in said beams without weakening the beams so that they are likely to be damaged by normal handling.
Claim 13
Dependent Claim
106 words
A pair of controlled expansion beams as set forth in claim 10 wherein said means comprises a generally rectangular aperture adjacent to the butted end of each beam, and a longitudinal tongue on the butted end of each beam extending alongside the other of said beams and being folded back through the aperture in said other beam, said tongues being longitudinally slidable in said apertures when the butted ends of said beams crush together and snugly fitting between the upper and lower edges of said apertures to hold said ends in alignment with each other normally and at least generally while said beams are crushing together.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-04 | 1978-05-06 | 1978-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-04 | 1982-05-06 | 1982-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-04 | 1986-05-06 | 1986-11-05 | $7700.00 | Window Closed / Lapsed |