US3866898A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pull down jaw
Assignee: Individual
•
Filing: 1973-04-16
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Granted: 1975-02-18
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Expires: 1993-04-16
Abstract
Abstract A pull-down jaw comprising two rectangular plates. Flexible elements engage the plates for lifting of one of the plates relative to the other plate, and bracing devices extending between the plates.
Inventors
- 👤 Ernst Spengler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:36
CPC Classifications
B; B25; B25B; B25B1/00; B25B1/24; B25B1/2405; B25B1/2473
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
172 words
Pull down jaw comprising two nearly equal size rectangularly shaped plates abutting each other, flexible elements engaging said plates for lifting of one of said plates relative to the other, screw joints for permitting bracing of said plates at a slant, said plates being provided with a plurality of bracing devices, one section of each bracing device terminating in a generated surface while the other section of the same bracing device is an indentation engageable by said generated surface, said generated surface being a truncated cone including an end of a screw which is mounted in one of said plates nearly perpendicular thereto, said plates bracing one another on these bracing devices only when not under load but abutting each other when under load, said plates including tapered cooperating grooves therein, said grooves being inclined at an angle of up to 8* in the direction of the nucleus of said plates, and said flexible elements being steel spriNg bands that are bent in the center thereof and clamped into said cooperating grooves.
Claim 2
Dependent Claim
172 words
Pull down jaw comprising two nearly equal size rectangularly shaped plates abutting each other, flexible elements engaging said plates for lifting of one of said plates relative to the other, screw joints for permitting bracing of said plates at a slant, said plates being provided with a plurality of bracing devices, one section of each bracing device terminating in a generated surface while the other section of the same bracing device is an indentation engageable by said generated surface, said generated surface being a truncated cone including an end of a screw which is mounted in one of said plates nearly perpendicular thereto, said plates bracing one another on these bracing devices only when not under load but abutting each other when under load, said plates including tapered cooperating grooves therein, said grooves being inclined at an angle of up to 8* in the direction of the nucleus of said plates, and said flexible elements being steel spriNg bands that are bent in the center thereof and clamped into said cooperating 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) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |