US4112649A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Boom section for telescopic crane boom
Assignee: TRUST COMPANY UNITED STATES
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Filing: 1977-08-26
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Granted: 1978-09-12
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Expires: 1997-08-26
Abstract
Abstract A large light-weight deflection-resistant telescopic boom section of hollow rectangular cross-section comprises spaced apart top and bottom plates and spaced apart vertical side plates welded therebetween inwardly of the side edges thereof. Longitudinal corner stiffeners of angular cross-section are welded between the outwardly extending portion of the top and bottom plates and the associated vertical side plate to shorten the effective height of the side plate, to stiffen the top and bottom plates, to increase the mechanical section properties, and to provide a flat built-in slide pad bearing surface. Vertical side stiffeners of U-shaped cross-section are welded to the vertical side plates at intervals therealong and to the longitudinal corner stiffeners to provide the buckling resistance and increased shear load capacity of side plates.
Inventors
- 👤 Robert A. Fritsch
- 👤 Narahari Gattu
- 👤 Lembit Vaerk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:44
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/62; B66C23/64; B66C23/70; B66C23/701; B66C23/707
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
174 words
In a hollow rectangular boom section for a telescopic crane boom: a pair of spaced apart first plates including a top plate and a bottom plate, each top plate and bottom plate having side edges; a pair of spaced side plates connected between and inwardly of said side edges of said first plates whereby outwardly projecting edge portions are defined on said first plates, each side plate being at right angles to said first plates; a plurality of longitudinal corner stiffeners, one for each corner of said boom section, each longitudinal corner stiffener connected between a side plate and the outwardly projecting edge portion of one of said first plates inwardly of a side edge thereof to shorten the effective height of a side plate, each longitudinal corner stiffener including a slide pad bearing portion spaced from and parallel to its associated side plate; and a plurality of side stiffeners in spaced apart relation along said side plates, each side stiffener connected to its associated side plate and to the longitudinal corner stiffeners therefor.
Claim 2
Dependent Claim
174 words
In a hollow rectangular boom section for a telescopic crane boom: a pair of spaced apart first plates including a top plate and a bottom plate, each top plate and bottom plate having side edges; a pair of spaced side plates connected between and inwardly of said side edges of said first plates whereby outwardly projecting edge portions are defined on said first plates, each side plate being at right angles to said first plates; a plurality of longitudinal corner stiffeners, one for each corner of said boom section, each longitudinal corner stiffener connected between a side plate and the outwardly projecting edge portion of one of said first plates inwardly of a side edge thereof to shorten the effective height of a side plate, each longitudinal corner stiffener including a slide pad bearing portion spaced from and parallel to its associated side plate; and a plurality of side stiffeners in spaced apart relation along said side plates, each side stiffener connected to its associated side plate and to the longitudinal corner stiffeners therefor.
Claim 3
Dependent Claim
17 words
A boom section according to claim 1 wherein each longitudinal corner stiffener is of angular cross-sectional configuration.
Claim 4
Dependent Claim
18 words
A boom section according to claim 2 wherein each of said side stiffeners is of generally U-shaped configuration.
Claim 5
Dependent Claim
43 words
A boom section according to claim 1 wherein each longitudinal corner stiffener is connected to a side plate along a line which is spaced from the edge of the side plate by about 1/10 to 2/10 of the height of said side plate.
Claim 6
Dependent Claim
21 words
A boom section according to claim 4 wherein each side plate is wider than each of said pair of first plates.
Claim 7
Dependent Claim
29 words
A boom section according to claim 5 wherein each side plate is wider than each of said pair of first plates in a ratio between about 2/3 and 3/4.
Claim 8
Dependent Claim
211 words
In a hollow rectangular boom section for a telescopic crane boom: a top plate having lateral edges; a bottom plate having lateral edges; a pair of spaced apart side plates disposed between and welded to said top plate and said bottom plate at locations inwardly of the lateral edges of said top plate and said bottom plate whereby said top plate and said bottom plates have outwardly projecting edge portions, each side plate being at right angles to said top plate and said bottom plate; a plurality of longitudinal corner stiffeners, one for each corner of said boom section, each longitudinal corner stiffener having an angular cross-section and including a flat side portion and an inwardly extending portion, each longitudinal corner stiffener being welded to a side plate and to an outwardly projecting edge portion of one of said top plates or bottom plates inwardly of a lateral edge thereof so that said flat side portion is spaced from and parallel to an associated side plate; and a plurality of vertical side stiffeners, each having a U-shaped cross-section, said vertical side stiffeners disposed in spaced apart relationship along said side plates, each vertical side stiffener being welded to a side plate and to the longitudinal corner stiffeners for the side plate.
Claim 9
Dependent Claim
211 words
In a hollow rectangular boom section for a telescopic crane boom: a top plate having lateral edges; a bottom plate having lateral edges; a pair of spaced apart side plates disposed between and welded to said top plate and said bottom plate at locations inwardly of the lateral edges of said top plate and said bottom plate whereby said top plate and said bottom plates have outwardly projecting edge portions, each side plate being at right angles to said top plate and said bottom plate; a plurality of longitudinal corner stiffeners, one for each corner of said boom section, each longitudinal corner stiffener having an angular cross-section and including a flat side portion and an inwardly extending portion, each longitudinal corner stiffener being welded to a side plate and to an outwardly projecting edge portion of one of said top plates or bottom plates inwardly of a lateral edge thereof so that said flat side portion is spaced from and parallel to an associated side plate; and a plurality of vertical side stiffeners, each having a U-shaped cross-section, said vertical side stiffeners disposed in spaced apart relationship along said side plates, each vertical side stiffener being welded to a side plate and to the longitudinal corner stiffeners for the side plate.
Claim 10
Dependent Claim
43 words
A boom section according to claim 7 wherein each longitudinal corner stiffener is connected to a side plate along a line which is spaced from the edge of the side plate by about 1/10 to 2/10 of the height of said side plate.
Claim 11
Dependent Claim
21 words
A boom section according to claim 8 wherein each side plate is wider than each of said pair of first plates.
Claim 12
Dependent Claim
29 words
A boom section according to claim 9 wherein each side plate is wider than each of said pair of first plates in a ratio between about 2/3 and 3/4.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-09-11 | 1982-03-13 | 1982-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-11 | 1986-03-13 | 1986-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-11 | 1990-03-13 | 1990-09-12 | $7700.00 | Window Closed / Lapsed |