US3856151A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telescopic boom and jib assembly with means to maintain a predetermined angular position therebetween
Assignee: Case LLC
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Filing: 1973-11-29
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Granted: 1974-12-24
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Expires: 1993-11-29
Abstract
Abstract This application discloses a crane having an extensible boom consisting of a plurality of boom sections telescoped through power means and a jib assembly pivotally connected to the outer end of the outer or tip section of the boom. The jib assembly is automatically held in a fixed angular position with respect to the boom by a cable assembly while the boom is extended and retracted. The cable assembly includes a cable having one end connected to the inner end of the tip section of the boom and entrained over a plurality of pulleys rotatable on the remaining sections of the boom with the opposite end connected to the free end of a mast structure pivoted on the outer end of the tip boom section. The mast structure is connected to the outer end of the jib assembly through a further cable. The cable assembly will automatically hold the jib assembly at a predetermined angle while the boom sections are extended and retracted relative to each other.
Inventors
- 👤 G Lamer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:06
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/62; B66C23/82; B66C23/64; B66C23/70; B66C23/701; B66C23/702
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
168 words
A crane including an extensible boom having a plurality of longitudinal hollow boom sections telescoped for extension and retraction with said boom including at least a base section and a tip section having a free end, power means for extending and retracting said boom section relative to each other, a jib assembly having one end pivotally connected adjacent said free end of said tip section, a cable assembly supporting said jib assembly in a predetermined angular position with respect to said boom, said cable assembly having one end connected to said jib assembly at a location spaced a substantial distance from the pivotal connection, said cable assembly having an opposite end connected inside said tip section adjacent the telescoping end, and a plurality of freely rotatable pulleys on said boom sections with said cable assembly entrained over said pulleys, said pulleys being arranged to maintain said predetermined angle between said boom and said jib assembly while said boom sections are being extended and retracted by said power means.
Claim 2
Dependent Claim
168 words
A crane including an extensible boom having a plurality of longitudinal hollow boom sections telescoped for extension and retraction with said boom including at least a base section and a tip section having a free end, power means for extending and retracting said boom section relative to each other, a jib assembly having one end pivotally connected adjacent said free end of said tip section, a cable assembly supporting said jib assembly in a predetermined angular position with respect to said boom, said cable assembly having one end connected to said jib assembly at a location spaced a substantial distance from the pivotal connection, said cable assembly having an opposite end connected inside said tip section adjacent the telescoping end, and a plurality of freely rotatable pulleys on said boom sections with said cable assembly entrained over said pulleys, said pulleys being arranged to maintain said predetermined angle between said boom and said jib assembly while said boom sections are being extended and retracted by said power means.
Claim 3
Dependent Claim
49 words
A crane as defined in claim 1, in which said extensible boom includes an intermediate section between said base section and said tip section with said plurality of pulleys including a pulley adjacent each end of said intermediate section and a pulLey adjacent each end of said base section.
Claim 4
Dependent Claim
71 words
A crane as defined in claim 1, in which said cable assembly includes a mast structure having one end pivotally connected adjacent said free end of said tip section, a first cable having one end connected to an opposite end of said mast and a second cable of fixed length having one end connected to said opposite end of said mast structure and an opposite end connected to said tip section.
Claim 5
Dependent Claim
49 words
A crane as defined in claim 3, in which said boom includes an intermediate section between said base section and said tip section with a pulley adjacent each end of said intermediate section and said cable entrained over said pulleys to produce cable overlapping portions in said intermediate sections.
References Cited (Backward Citations)
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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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |