US3885686A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power lifting attachment for vehicles
Assignee: Individual
•
Filing: 1973-01-11
•
Granted: 1975-05-27
•
Expires: 1993-01-11
Abstract
Abstract A lifting and loading apparatus to be used in connection with vehicles, for example pickup trucks, to load heavy articles into the same. The apparatus has a pair of tracks which are mounted on a vehicle. A pair of carriages are mounted on the tracks for movement with respect thereto. Power lifting arms are pivotably mounted on the carriage and rigidly support at outer ends a platform or other similar lifting means so that the platform or other means maintains a predetermined relationship with respect to the horizontal during lifting operations. A reversible direct current motor operates the lifting arms through a screw rod. Means are provided to control the motor to selectively turn the motor off and on and also to stop the motor upon the arms reaching a predetermined height or meeting a predetermined resistance during downward descent. The carriages are moved along the tracks by a hand-operated winch which locks the carriages in selective positions along the rails. Special cord holding means are provided to keep the electrical cord for the motor taut as the carriage moves along the tracks. Means are provided for locking the arms in selective positions.
Inventors
- 👤 Barton G Siebring
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:05
CPC Classifications
B; B60; B60P; B60P1/00; B60P1/48; B60P1/483
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
273 words
In a power lifting apparatus for vehicles comprising: first and second tracks; means for mounting said tracks on a vehicle; first and second carriages mounted on said first and second tracks respectively for movement therealong; first and second lifting arms pivotably mounted on said carriages; power means for raising and lowering in unison said first and second lifting arms about their pivotable mountings, whereby the free end of said arms can be raised and lowered in selected positions along said tracks for raising and transferring articles into said vehicle, the improvement which comprises: said power means includes a ball screw assembly including a threaded rod, and a ball bearing nut threadably engaging the threaded rod and pivotably mounted to said first lifting arm whereby rotation of the threaded rod causes the ball bearing nut to ride along the threaded rod, the threaded rod being pivotably mounted at one end portion to said first carriage so that rotation of said threaded rod with respect to the ball bearing nut causes raising and lowering of said first lifting arm about its pivotable mounting; motor means mounted on said ball screw assembly for movement therewith; means coupling said motor means to said ball screw assembly for rotating said threaded rod; and braking means for applying substantial braking action to said ball screw assembly during downward movement thereof so as to hold said arm in any one of a number of positions with respect to said carriage and for applying very minimal braking to said ball screw assembly during upward movement thereof, so as to permit lifting of large loads without undue drag from said braking means.
Claim 2
Dependent Claim
273 words
In a power lifting apparatus for vehicles comprising: first and second tracks; means for mounting said tracks on a vehicle; first and second carriages mounted on said first and second tracks respectively for movement therealong; first and second lifting arms pivotably mounted on said carriages; power means for raising and lowering in unison said first and second lifting arms about their pivotable mountings, whereby the free end of said arms can be raised and lowered in selected positions along said tracks for raising and transferring articles into said vehicle, the improvement which comprises: said power means includes a ball screw assembly including a threaded rod, and a ball bearing nut threadably engaging the threaded rod and pivotably mounted to said first lifting arm whereby rotation of the threaded rod causes the ball bearing nut to ride along the threaded rod, the threaded rod being pivotably mounted at one end portion to said first carriage so that rotation of said threaded rod with respect to the ball bearing nut causes raising and lowering of said first lifting arm about its pivotable mounting; motor means mounted on said ball screw assembly for movement therewith; means coupling said motor means to said ball screw assembly for rotating said threaded rod; and braking means for applying substantial braking action to said ball screw assembly during downward movement thereof so as to hold said arm in any one of a number of positions with respect to said carriage and for applying very minimal braking to said ball screw assembly during upward movement thereof, so as to permit lifting of large loads without undue drag from said braking means.
Claim 3
Dependent Claim
28 words
A power lifting apparatus according to claim 1 and further comprising means for locking said first and second carriages in selected positions along said first and second tracks.
Claim 4
Dependent Claim
64 words
A power lifting apparatus according to claim 2 wherein said locking means includes a winch mounted on one of said carriages and winding two cables in opposite directions, one of said cables being secured at one end of the track mounting said one carriage carriage and the other of said cables being secured to an opposite end of said track mounting said one carriage.
Claim 5
Dependent Claim
28 words
A power lifting apparatus according to claim 1 and further comprising means for rigidly joining said first and second carriages together for movement in unison along said tracks.
Claim 6
Dependent Claim
48 words
A power lifting apparatus according to claim 1 and further comprising a platform and means for supporting said platform on the free ends of said first and second arms, and further including means for maintaining said platform level as said first and second arms are raised and lowered.
Claim 7
Dependent Claim
44 words
A power lifting apparatus according to claim 1 wherein said motor means includes an electric motor and further comprising means for cutting off the flow of Current to said electric motor when a predetermined resistance to downward movement is encountered by said lifting arms.
Claim 8
Dependent Claim
33 words
A power lifting apparatus according to claim 6 and further comprising means to cut off the flow of electric current to said electric motor responsive to said arm reaching a predetermined upper limit.
Claim 9
Dependent Claim
38 words
A power lifting apparatus according to claim 1 wherein said motor means includes an electric motor; and further comprising means to limit the upward movement of said lifting arms responsive to said arms reaching a predetermined upper limit.
Claim 10
Dependent Claim
40 words
A power lifting apparatus accordig to claim 1 wherein an electrical cord is electrically coupled to said motor for supplying electrical current thereto; and resilient means maintain said electric cord in taut condition as said carriages move along said tracks.
Claim 11
Dependent Claim
77 words
A power lifting apparatus according to claim 4 and further comprising: a second ball screw assembly including a threaded rod mounted on said second carriage between said second carriage and said second lifting arm; and means for driving said threaded rod of said second ball screw assembly synchronously with said first ball screw assembly threaded rod, whereby said first and second arms are driven upwardly and downwardly in unison by said first and second ball screw assemblies.
Claim 12
Dependent Claim
60 words
A power lifting apparatus according to claim 10 and further comprising a guard track extending between and connected to said first and second ball screw assemblies, and said driving means includes a chain and gearing on said threaded rods, said chain and drivingly engaging said gearing, so that said ball screw assemblies and said guard track move as a unit.
Claim 13
Dependent Claim
142 words
A power lifting apparatus according to claim 1 wherein said braking means comprises: a drum coupled to said threaded rod for rotation therewith; a brake strap at least partially wrapped around said drum, said brake strap being of a material so as to produce a frictional drag when wrapped tightly around said drum; means rigidly mounting one end of said brake strap with respect to said drum; and means resiliently mounting the other end of said brake strap with respect to said drum so that said drum works against the tension of said resilient mounting to unwrap said brake strap when said screw rod rotates so as to raise said first lifting arm and said drum works against said fixed mounting to wrap said brake strap around said drum when said screw rod rotates so as to lower said first lifting arm.
Claim 14
Dependent Claim
37 words
A power lifting apparatus according to claim 1 and further comprising protective cover means for covering said threaded rod, said protective cover means mounted on said carriage and slidably mounted with respect to said ball bearing nut.
Claim 15
Dependent Claim
263 words
A power lifting apparatus for vehicles comprising in combination: first and second tracks; means for mounting said tracks on a vehicle; first and second carriages mounted on said first and second tracks respectively for movement therealong; first and second lifting arms each being hollow substantially along the length thereof and pivotably mounted on a horizontal axis on said first and second carriages, respectively in spaced relationship to each other for rotational movement on said carriages; a platform; means for supporting said platform on the free ends of said first and second lifting arms; and means for maintaining said platform level as said lifting arms are rotated about their pivotable mountings on said carriages, said means for maintaining said platform level including a first guide means with a curved upper surface having a center of curvature on the pivotable mounting axis of said first arms, a cable drawn over the curved surface and rigidly coupled to said first guide means, said cable passing through the interior of said hollow arm, a second guide means with a curved upper surface of the curvature to the first guide means curved surface rotatably mounted within the free end of said first lifting arm and sEcured nonrotatably to said platform supporting means, said cable being drawn over said curved surface of the second guide means and means for rigidly coupling said cable to said second guide means so that said cable is maintained taut as said first lifting arm rotates and so as to maintain said platform support means angularly fixed with respect to said first support means.
Claim 16
Dependent Claim
263 words
A power lifting apparatus for vehicles comprising in combination: first and second tracks; means for mounting said tracks on a vehicle; first and second carriages mounted on said first and second tracks respectively for movement therealong; first and second lifting arms each being hollow substantially along the length thereof and pivotably mounted on a horizontal axis on said first and second carriages, respectively in spaced relationship to each other for rotational movement on said carriages; a platform; means for supporting said platform on the free ends of said first and second lifting arms; and means for maintaining said platform level as said lifting arms are rotated about their pivotable mountings on said carriages, said means for maintaining said platform level including a first guide means with a curved upper surface having a center of curvature on the pivotable mounting axis of said first arms, a cable drawn over the curved surface and rigidly coupled to said first guide means, said cable passing through the interior of said hollow arm, a second guide means with a curved upper surface of the curvature to the first guide means curved surface rotatably mounted within the free end of said first lifting arm and sEcured nonrotatably to said platform supporting means, said cable being drawn over said curved surface of the second guide means and means for rigidly coupling said cable to said second guide means so that said cable is maintained taut as said first lifting arm rotates and so as to maintain said platform support means angularly fixed with respect to said first support means.
Claim 17
Dependent Claim
22 words
A power lifting apparatus according to claim 14 and further comprising means to rotate said lifting arms about their respective pivotable mountings.
Claim 18
Dependent Claim
63 words
A power lifting apparatus according to claim 14 wherein said cable is coupled to said first support means through a first circular guide surface, said guide means mounted to the free end of said first lifting arm is a second circular guide means of a size equal to said first guide surface, and said cable is coupled to said second circular guide surface.
References Cited (Backward Citations)
US2734645A
Cited
US2660319A
Cited
US2567178A
Cited
US2683545A
Cited
US2911118A
Cited
US2928560A
Cited
US3258139A
Cited
US3276610A
Cited
US3341038A
Cited
US3547284A
Cited
US3613918A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |