US3717067A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Underlayment fastening device
Assignee: United States Department of Agriculture
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Filing: 1971-01-07
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Granted: 1973-02-20
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Expires: 1991-01-07
Abstract
Abstract A nail-like device to securely fasten plywood underlayment to plywood subflooring without the accompanying nail popping and dimpling problems that often occur when nails of conventional design are used. The device is comprised of a shaft divided along its length into two sections of different diameters with each section having a plurality of annular grooves. The upper section of the shaft, which is normally embedded in the underlayment, has a larger diameter and coarser annular grooves than the lower section, which is normally embedded in the subflooring. The driving head at the top of the shaft is completely embeddable. These elements cooperate to prevent the device from withdrawing from the underlayment or otherwise causing surface irregularities which would be visible through a thin resilient tile floor.
Inventors
- 👤 C Vick
- 👤 R Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:01
CPC Classifications
F; F16; F16B; F16B15/00; F16B15/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
304 words
A nail-like device for fastening underlayment to subflooring, which avoids later nail popping and dimpling problems, comprising in combination: a. a solid shaft divided into upper and lower sections along its length, said upper section having a larger diameter than said lower section and a length sufficient to embed said upper section it the thickness of said underlayment, and said lower section of a length sufficient to embed it in the thickness of said subflooring, b. a plurality of annular grooves along the length of, and uniformly proportional in size to the diameters of each of said sections; each of said grooves being formed by a base the same diameter as the shaft section on which it is located, and a crown, the diameter of which is larger than the base diameter on that section, c. said base and crown diameters on the upper section necessarily being larger than the base and crown diameters on the lower section, such that greater withdrawal resistance is found in the upper section which is embedded in said underlayment than in the lower section which is embedded in said subflooring, thereby limiting possible slippage to said lower section as said underlayment and subflooring alternately shrink and swell during variable moisture periods, d. the upper end of said upper shaft section being truncated perpendicular to the longitudinal axis of said shaft to form a completely embeddable driving head having a diameter no greater than the maximum diameter of said shaft, e. the lower end of said lower shaft section being tapered to form a point, and f. said crowns on each section comprising a flat surface extending generally perpendicular to the axis of said shaft and facing said driving head, the surface of each said groove extending from the crown to the base defining the frustum of a cone.
Claim 2
Dependent Claim
304 words
A nail-like device for fastening underlayment to subflooring, which avoids later nail popping and dimpling problems, comprising in combination: a. a solid shaft divided into upper and lower sections along its length, said upper section having a larger diameter than said lower section and a length sufficient to embed said upper section it the thickness of said underlayment, and said lower section of a length sufficient to embed it in the thickness of said subflooring, b. a plurality of annular grooves along the length of, and uniformly proportional in size to the diameters of each of said sections; each of said grooves being formed by a base the same diameter as the shaft section on which it is located, and a crown, the diameter of which is larger than the base diameter on that section, c. said base and crown diameters on the upper section necessarily being larger than the base and crown diameters on the lower section, such that greater withdrawal resistance is found in the upper section which is embedded in said underlayment than in the lower section which is embedded in said subflooring, thereby limiting possible slippage to said lower section as said underlayment and subflooring alternately shrink and swell during variable moisture periods, d. the upper end of said upper shaft section being truncated perpendicular to the longitudinal axis of said shaft to form a completely embeddable driving head having a diameter no greater than the maximum diameter of said shaft, e. the lower end of said lower shaft section being tapered to form a point, and f. said crowns on each section comprising a flat surface extending generally perpendicular to the axis of said shaft and facing said driving head, the surface of each said groove extending from the crown to the base defining the frustum of a cone.
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) | 1976-02-20 | 1976-08-21 | 1977-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-20 | 1980-08-21 | 1981-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-20 | 1984-08-21 | 1985-02-20 | $7700.00 | Window Closed / Lapsed |