US3796282A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilizer for elevatable platform
Assignee: Individual
•
Filing: 1972-10-17
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Granted: 1974-03-12
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Expires: 1992-10-17
Abstract
Abstract Apparatus in which a platform is supported by a scissors linkage on each side of the platform and upper and lower hydraulic rams are connected to each scissors linkage with means for supplying hydraulic fluid to the hydraulic rams to expand them to raise the linkage. Each lower ram is connected to an upper ram on the opposite linkage in such a way that the interconnected rams expand in unison and by equal amounts to maintain the platform level as it is being raised regardless of the loading on the platform.
Inventors
- 👤 D Denier
- 👤 L Garrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:12
CPC Classifications
B; B66; B66F; B66F11/00; B66F11/04; B66F11/042; E; E04; E04G; E04G1/00; E04G1/18; E04G1/22
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
80 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage to expand said linkages to raise said platform on application of hydraulic fluid to said rams, means hydraulically connecting each lower ram to an upper ram on the opposite side of said linkage to drive said upper ram the same distance as the loweR ram to which it is connected.
Claim 2
Dependent Claim
80 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage to expand said linkages to raise said platform on application of hydraulic fluid to said rams, means hydraulically connecting each lower ram to an upper ram on the opposite side of said linkage to drive said upper ram the same distance as the loweR ram to which it is connected.
Claim 3
Dependent Claim
46 words
Elevator apparatus according to claim 1 in which said lower rams are double acting, one end of each lower ram being hydraulically connected to the upper ram on the opposite side of said linkage to drive said upper ram with fluid expelled from said lower ram.
Claim 4
Dependent Claim
30 words
Elevator apparatus according to claim 2 in which each upper ram has an effective piston area identical to the piston area of said lower ram which drives said upper ram.
Claim 5
Dependent Claim
86 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage, each lower ram including a cylinder having a port at each end and a piston and rod slidable in said cylinder, means hydraulically connecting the first of said ports to the upper ram on the opposite side of said linkage, and means supplying hydraulic fluid under pressure to the second port of each said lower ram.
Claim 6
Dependent Claim
86 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage, each lower ram including a cylinder having a port at each end and a piston and rod slidable in said cylinder, means hydraulically connecting the first of said ports to the upper ram on the opposite side of said linkage, and means supplying hydraulic fluid under pressure to the second port of each said lower ram.
Claim 7
Dependent Claim
18 words
Elevator apparatus as in claim 4 further comprising, means for supplying make up fluid to said upper rams.
Claim 8
Dependent Claim
25 words
Elevator apparatus as in claim 5 in which said make up fluid is supplied at substantially lower pressure than said first mentioned fluid supplying means.
Claim 9
Dependent Claim
79 words
Elevator apparatus as in claim 4 in which said hydraulic fluid supplying means comprises, a motor driven pump having an outlet, conduits connecting said pump to said second ports, a conduit interconnecting said first ports, two one-way check valves in said conduit permitting flow from the center of said conduit toward said rams, means including a pressure reducing valve connecting said pump to said conduit, and conduits connected between check valves and rams respectively to said opposite upper rams.
Claim 10
Dependent Claim
102 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage to expand said linkages to raise said platform on application of hydraulic fluid to said rams, means connecting each lower ram to an upper ram on the opposite side of said linkage, said upper ram being slaved to its respective lower ram to expand said upper ram in unison with and to the same extent as said respective lower ram, and means for supplying hydraulic fluid under pressure to said lower rams.
Claim 11
Dependent Claim
102 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage to expand said linkages to raise said platform on application of hydraulic fluid to said rams, means connecting each lower ram to an upper ram on the opposite side of said linkage, said upper ram being slaved to its respective lower ram to expand said upper ram in unison with and to the same extent as said respective lower ram, and means for supplying hydraulic fluid under pressure to said lower rams.
Claim 12
Dependent Claim
95 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage to expand said linkages to raise said platform on application of hydraulic fluid to said rams, means interconnecting said rams to provide one master ram on each linkage connected to a slave ram on the opposite linkage, the slave rams expanding in unison with and to the same extent as said master rams, and means for supplying hydraulic fluid under pressure to said master rams.
Claim 13
Dependent Claim
95 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, upper and lower rams connected to each linkage to expand said linkages to raise said platform on application of hydraulic fluid to said rams, means interconnecting said rams to provide one master ram on each linkage connected to a slave ram on the opposite linkage, the slave rams expanding in unison with and to the same extent as said master rams, and means for supplying hydraulic fluid under pressure to said master rams.
Claim 14
Dependent Claim
80 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, at least one master ram connected to one of said linkages and a slave ram connected to the opposite linkage, means for supplying hydraulic fluid under pressure to the master ram, means hydraulically interconnecting the master and slave rams to require the slave ram to extend in unison with and to the same extent as the master ram.
Claim 15
Dependent Claim
80 words
Elevator apparatus comprising, a base, a scissors linkage mounted on each side of said base, a platform mounted on said scissors linkage, at least one master ram connected to one of said linkages and a slave ram connected to the opposite linkage, means for supplying hydraulic fluid under pressure to the master ram, means hydraulically interconnecting the master and slave rams to require the slave ram to extend in unison with and to the same extent as the master ram.
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) | 1977-03-11 | 1977-09-10 | 1978-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-11 | 1981-09-10 | 1982-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-11 | 1985-09-10 | 1986-03-12 | $7700.00 | Window Closed / Lapsed |