US3863771A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gantry cranes
Assignee: Individual
•
Filing: 1973-12-06
•
Granted: 1975-02-04
•
Expires: 1993-12-06
Abstract
Abstract A movable gantry crane for erecting a wide span structure comprising several bridge-like sub-structures arranged side by side in spaced relationship, which crane comprises: a horizontal girder long enough to span the structure and supported at each side of the structure by movable support columns; a platform suspended from the girder from hangers so as to lie beneath a sub-structure to be erected and enable work to be carried on without interference with the area spanned by the structure; there being at least one set of hangers in front of this substructure, and at least one other set of hangers behind it and which can be displaced to permit the crane and the platform to be moved forward when the sub-structure has attained a stable condition; and a lifting device movable along the girder between the sets of hangers.
Inventors
- 👤 Charles Herbert Dobbie
- 👤 John David Winders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:19
CPC Classifications
E; E04; E04H; E04H1/00; B; B66; B66C; B66C19/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49828; Y10T29/49831
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
166 words
A movable gantry crane useful in the erection of a structure comprising several bridge-like sub-structures arranged side by side in spaced relationship; which crane comprises a girder long enough to span the structure, supported by movable supporting columns, at least two sets of hangers which suspend a platform from the girder in a position to lie beneath a bridge-like substructure to be erected with the aid of the crane, at least one set being disposed to occupy a position in front of the said substructure and at least one other set being disposed to occupy a position to the rear of the said sub-structure, a lifting device movable along the girder between sets of hangers disposed to occupy positions respectively in front of and to the rear of the said sub-structure, and the hangers of the said other set or sets being removable or displaceable to permit the crane including the platform to be moved forwards when this suB-structure has been made self-supporting and laterally stable.
Claim 2
Dependent Claim
166 words
A movable gantry crane useful in the erection of a structure comprising several bridge-like sub-structures arranged side by side in spaced relationship; which crane comprises a girder long enough to span the structure, supported by movable supporting columns, at least two sets of hangers which suspend a platform from the girder in a position to lie beneath a bridge-like substructure to be erected with the aid of the crane, at least one set being disposed to occupy a position in front of the said substructure and at least one other set being disposed to occupy a position to the rear of the said sub-structure, a lifting device movable along the girder between sets of hangers disposed to occupy positions respectively in front of and to the rear of the said sub-structure, and the hangers of the said other set or sets being removable or displaceable to permit the crane including the platform to be moved forwards when this suB-structure has been made self-supporting and laterally stable.
Claim 3
Dependent Claim
64 words
A gantry crane as claimed in claim 1 in which there is one set of hangers disposed to occupy a position in front of the said sub-structure and two sets of removable or displaceable hangers disposed to occupy positions to the rear of the said sub-structure at different distances therefrom sub-structure, said two sets being disposed at different distances rearwardly from said last-mentioned sub-structure.
Claim 4
Dependent Claim
31 words
A gantry crane as claimed in claim 1 in which there is another lifting device movable along said girder to the rear of said at least one other set of hangers.
Claim 5
Dependent Claim
21 words
A gantry crane as claimed in claim 1 in which said platform is long enough to encompass three of said sub-structures.
Claim 6
Dependent Claim
58 words
A gantry crane as claimed in claim 4 in which there is another lifting device movable along said girder to the rear of said at least one other set of hangers and said crane has a forward working bay served by said first-mentioned movable lifting device and a rear working bay served by said other movable lifting device.
Claim 7
Dependent Claim
37 words
A gantry crane as claimed in claim 4 in which said platform is adapted to co-operate with roller supports therefor mounted on at least one of said sub-structures which is in a self-supporting and laterally stable condition.
Claim 8
Dependent Claim
23 words
A gantry crane as claimed in claim 1 in which at least one end of said girder projects beyond the respective supporting column.
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) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |