Patent US3784028A successfully refreshed from Google Patents.
US3784028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gantry crane
Assignee: Lift Tech International Inc
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Filing: 1972-06-09
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Granted: 1974-01-08
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Expires: 1992-06-09
Abstract
Abstract A heavy duty gantry crane suitable for railroad piggyback operations. Forming the bridge is a pair of spaced apart parallel girders supported on steel legs and wheeled trucks for operating over runway rails. Interconnecting trolleys laterally positionable on the bridge operate lift forks in controllably guided horizontal and vertical planes. A pendant push-button station connected to a widely pivotal swivel boom enables one man operational control from ground level.
Inventors
- 👤 K Stewart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:50
CPC Classifications
B; B66; B66C; B66C19/00; B66C19/002; B66C13/00; B66C2700/00; B66C2700/01; B66C2700/012; B66C2700/017
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
193 words
A gantry crane adapted for semi-trailer piggyback railroad service comprising in combination: a. a bridge for spanning a semi-trailer piggy-back work area to be serviced; b. mobile bridge support means for locating the bridge longitudinally within the work area; c. a pair of oppositely extending lift frames individually supported from said bridge with each lift frame of said pair being positionable into and out of underlying support relation with a semi-trailer to be relocated within the work area; d. first drive means for presettable vertical positioning of said lift frames into and out of said support relation; e. second drive means for presettable horizontal positioning of said lift frames on said bridge relative to each other into and out of said support relation; f. third drive means for locating said positioned lift framEs on said bridge transversely within the work area between said bridge support means for transporting a semi-trailer in support relation on said lift frames; and g. guide means effective for maintaining a substantially rigid transverse planar relation between the paths of vertical and horizontal movement incurred in the positioning of said lift frames by said first and second drive means.
Claim 2
Dependent Claim
193 words
A gantry crane adapted for semi-trailer piggyback railroad service comprising in combination: a. a bridge for spanning a semi-trailer piggy-back work area to be serviced; b. mobile bridge support means for locating the bridge longitudinally within the work area; c. a pair of oppositely extending lift frames individually supported from said bridge with each lift frame of said pair being positionable into and out of underlying support relation with a semi-trailer to be relocated within the work area; d. first drive means for presettable vertical positioning of said lift frames into and out of said support relation; e. second drive means for presettable horizontal positioning of said lift frames on said bridge relative to each other into and out of said support relation; f. third drive means for locating said positioned lift framEs on said bridge transversely within the work area between said bridge support means for transporting a semi-trailer in support relation on said lift frames; and g. guide means effective for maintaining a substantially rigid transverse planar relation between the paths of vertical and horizontal movement incurred in the positioning of said lift frames by said first and second drive means.
Claim 3
Dependent Claim
39 words
A gantry crane according to claim 1 in which said first drive means includes first and second trolley means on said bridge each operative for vertically positioning one lift frame of said pair in coordinated relation to the other.
Claim 4
Dependent Claim
67 words
A gantry crane according to claim 2 in which said lift frames include horizontal lip members and non-circular vertical tubes connected to said lip members for effecting said underlying support relation and said guide means include vertically extending tube guides secured to said first and second trolley means to receive and vertically guide said tubes in the course of vertical lift frame positioning by said trolley means.
Claim 5
Dependent Claim
35 words
A gantry crane according to claim 3 in which said tubes are rectangular in cross-section and said tube guides include vertically displaced guide rollers in surface guiding engagement against opposite exterior surfaces of said tubes.
Claim 6
Dependent Claim
30 words
A gantry crane according to claim 3 in which said third drive means is operatively connected to said first and second trolley means for effecting trolley traversal of said bridge.
Claim 7
Dependent Claim
35 words
A gantry crane according to claim 3 in which said guide means includes horizontal guide rails on said bridge commonly supporting said first and second trolley means for horizontal positioning by said second drive means.
Claim 8
Dependent Claim
25 words
A gantry crane according to claim 6 including a lead screw interconnecting said first and second trolley means and operative by said second drive means.
Claim 9
Dependent Claim
45 words
A gantry crane according to claim 7 including pendant control means for selective operator actuation of said first, second and third drive means and a hinge connected swivel boom supporting said pendant control means for operator positioning within a predetermined arcuate range of operator viewing.
Claim 10
Dependent Claim
21 words
A gantry crane according to claim 8 in which said mobile bridge support means includes mobile trucks adapted for rail travel.
Claim 11
Dependent Claim
35 words
A gantry crane according to claim 2 in which said guide means includes horizontal guide rails on said bridge commonly supporting said first and second trolley means for horizontal positioning by said second drive means.
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) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |