US4873900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screw driving device
Assignee: Individual
•
Filing: 1986-12-08
•
Granted: 1989-10-17
•
Expires: 2006-12-08
Abstract
Abstract An improved device is disclosed for driving slotted head fasteners. The invention involves the use of a straight bit with parallel opposing surfaces to apply torque to the fastener slot over an increased area and reduce the tendency of the bit to slip out of the slot.
Inventors
- 👤 Massimo Ciumaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:31
CPC Classifications
B; B25; B25B; B25B15/00; B25B15/001; B25B15/004; B25B15/007
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
167 words
A screw driving device comprising: a shank; a bit of rectangular cross-section formed at an end of the shank, two opposing surfaces of said bit being parallel to one another, parallel to the longitudinal axis of the shank and, when inserted into a screw slot, parallel to the longitudinal axis of the screw slot; a flat surface on an end of said bit, wherein said flat surface is perpendicular to the longitudinal axis of said shank; a means for applying torque to said shank; and a blade of rectangular cross-section formed onto the end of said shank, upon which said bit is formed, wherein said blade tapers outwardly on all sides from said shank to a dimention greater than the diameter of said shank and wherein said blade thence tapers inwardly on all sides to the point where said bit is formed, the bit having a cross-sectional area not greater than the cross-sectional area of the blade at the point at which the blade meets the bit.
Claim 2
Dependent Claim
167 words
A screw driving device comprising: a shank; a bit of rectangular cross-section formed at an end of the shank, two opposing surfaces of said bit being parallel to one another, parallel to the longitudinal axis of the shank and, when inserted into a screw slot, parallel to the longitudinal axis of the screw slot; a flat surface on an end of said bit, wherein said flat surface is perpendicular to the longitudinal axis of said shank; a means for applying torque to said shank; and a blade of rectangular cross-section formed onto the end of said shank, upon which said bit is formed, wherein said blade tapers outwardly on all sides from said shank to a dimention greater than the diameter of said shank and wherein said blade thence tapers inwardly on all sides to the point where said bit is formed, the bit having a cross-sectional area not greater than the cross-sectional area of the blade at the point at which the blade meets the bit.
Claim 3
Dependent Claim
22 words
The screw driving device of claim 1 wherein said means of applying torque is longitudinal handle with alternating longitudinal ribs and grooves.
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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) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-16 | 2001-04-17 | 2001-10-17 | $7700.00 | Window Closed / Lapsed |