Patent US3722933A successfully refreshed from Google Patents.
US3722933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Expansion joint for a fire-rated ceiling system
Assignee: Armstrong World Industries Inc
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Filing: 1971-05-07
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Granted: 1973-03-27
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Expires: 1991-05-07
Abstract
Abstract The cross member of a ceiling system is connected to the main runner of a ceiling system by a slide lock tab. A tab is bent at a 90* angle to the longitudinal axis of the cross runner. This tab slides into a fastener on the main runner structure. The connecting element between the cross member proper and the tab is corrugated so that, during a fire condition, the cross member can expand without buckling. Expansion occurs due to the collapse of the corrugated structure.
Inventors
- 👤 E Nute
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:44
CPC Classifications
F; F16; F16B; F16B7/00; F16B7/04; F16B7/044; F16B7/048; F16B7/0486; E; E04; E04B; E04B9/00; E04B9/06; E04B9/12; E04B9/127; F16B2200/00; F16B2200/63; Y; Y10; Y10T; Y10T403/00; Y10T403/46
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
156 words
A ceiling suspension system in the form of a grid comprising uniformly spaced main runner members extending parallel to each other, a series of cross members extending between the main runner members to define the grid pattern, the improvement comprising an expansion joint for connecting together the cross member to the main runner member, the joint comprising a fastening means on the vertical rib of the main runner and a tab on an extension from the vertical rib of the cross member, the extension between the main body of the vertical rib of The cross member and the tab being corrugated with the folds of the corrugations being transverse to the longitudinal axis of the web, said tab being connected to the fastening means of the main runner to connect the main runner and cross member together and the corrugated structure permitting, through its collapsing, the expansion of the cross member under the application of heat.
Claim 2
Dependent Claim
156 words
A ceiling suspension system in the form of a grid comprising uniformly spaced main runner members extending parallel to each other, a series of cross members extending between the main runner members to define the grid pattern, the improvement comprising an expansion joint for connecting together the cross member to the main runner member, the joint comprising a fastening means on the vertical rib of the main runner and a tab on an extension from the vertical rib of the cross member, the extension between the main body of the vertical rib of The cross member and the tab being corrugated with the folds of the corrugations being transverse to the longitudinal axis of the web, said tab being connected to the fastening means of the main runner to connect the main runner and cross member together and the corrugated structure permitting, through its collapsing, the expansion of the cross member under the application of heat.
Claim 3
Dependent Claim
62 words
The structure of claim 1 wherein the horizontal flange of the cross member is provided with a lip which overlies the upper surface of the horizontal flange of the main runner member so that the flange of the cross member will slide up over the flange of the main runner member when the cross member expands due to the influence of heat.
Claim 4
Dependent Claim
69 words
The structure of claim 2 wherein the fastening means on the main runner member vertical rib is a dual tab structure forming a channel arrangement into which the tab structure of the cross member may be slid and a detent structure on the tab and vertical rib of the main runner to frictionally hold the tab structure from sliding out of the fastening means of the main runner structure.
Claim 5
Dependent Claim
21 words
The structure of claim 1 wherein the corrugated structure is an integral part of the vertical rib of the cross member.
Claim 6
Dependent Claim
19 words
The structure of claim 1 wherein the corrugated structure is provided with a plurality of alternating ridges and grooves.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |