US4409761A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Roof construction system holding roof membranes in place by suction forces
Assignee: Individual
•
Filing: 1981-04-03
•
Granted: 1983-10-18
•
Expires: 2001-04-03
Abstract
Abstract A roof construction system wherein loosely-laid membranes on the top of a roof are held in place on the roof by suction forces when the wind blows, the suction forces varying directly in proportion to the wind velocity which would otherwise tend to lift the membrane so that frontal pressure and drag could dislodge or damage the roofing.
Inventors
- 👤 Thomas J. Bechtel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:31
CPC Classifications
E; E04; E04D; E04D13/00; E04D13/17; E04D5/00; E04D5/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
79 words
A roof system comprising a roof surface, a roof membrane positioned on said roof surface, a suction inlet located between said roof membrane and said roof surface, a housing rotatably connected to said suction inlet, a shaft mounted in said housing positioned parallel to the plane of said roof surface, an exhaust fan mounted on said shaft, and means for operating said exhaust fan comprising a windmill attached to said shaft and positioned on the exterior of said housing.
Claim 2
Dependent Claim
79 words
A roof system comprising a roof surface, a roof membrane positioned on said roof surface, a suction inlet located between said roof membrane and said roof surface, a housing rotatably connected to said suction inlet, a shaft mounted in said housing positioned parallel to the plane of said roof surface, an exhaust fan mounted on said shaft, and means for operating said exhaust fan comprising a windmill attached to said shaft and positioned on the exterior of said housing.
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) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |