US3756375A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Material handling apparatus
Assignee: Dravo Corp
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Filing: 1971-10-13
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Granted: 1973-09-04
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Expires: 1991-10-13
Abstract
Abstract Material handling apparatus having particular application to continuous unloading of bulk cargo from ships is disclosed. Basically, the apparatus includes a vertical mast with a laterally extending boom pivotally supported at one end to the mast. A power operated trolley is supported by the boom and is arranged, as with cooperating wheels and rails, to move longitudinally along the boom. A bucket elevator ladder frame is pivotally mounted at its upper end portion to the trolley. The ladder frame supports upper and lower sprockets, the upper sprocket preferably having larger diameters than the lower ones. An endless chain means forming a closed loop is supported by the sprockets. Spaced buckets are fixed to the chain means. A conveyor is carried by the boom and is arranged to receive material discharged from the buckets as they move around the upper sprockets, and to convey the material toward the mast. Hoist means supported by the mast are provided for lifting and lowering the boom. Counterweights are supported by the mast and are connected to the boom for counterbalancing the weight of the boom.
Inventors
- 👤 A Briggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:47
CPC Classifications
B; B65; B65G; B65G67/00; B65G2814/00; B65G2814/03; B65G2814/0397
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
172 words
A material handling apparatus comprising: an upwardly extending support mast; a laterally extending boom pivotally supported at one end to said mast; a trolley supported by said boom and arranged to move longitudinally along the boom; power means for driving said trolley along said boom; an elongated rigid bucket elevator ladder frame pivotally supported at its upper end to said trolley; means operative with said ladder frame for pivoting same with respect to said trolley; upper and lower sprockets rotatably supported by said ladder frame; drive means for rotating one of said sprockets; endless chain means forming a closed loop around said sprockets and including spaced buckets carried by said chain means; conveyor means carried by said boom and arranged receive material discharged from said buckets as they move around said upper sprockets and to convey the material toward said mast; hoist means supported by said mast for lifting and lowering said boom; and counterweight means supported by said mast and connected to said boom for counterbalancing the load on said boom.
Claim 2
Dependent Claim
172 words
A material handling apparatus comprising: an upwardly extending support mast; a laterally extending boom pivotally supported at one end to said mast; a trolley supported by said boom and arranged to move longitudinally along the boom; power means for driving said trolley along said boom; an elongated rigid bucket elevator ladder frame pivotally supported at its upper end to said trolley; means operative with said ladder frame for pivoting same with respect to said trolley; upper and lower sprockets rotatably supported by said ladder frame; drive means for rotating one of said sprockets; endless chain means forming a closed loop around said sprockets and including spaced buckets carried by said chain means; conveyor means carried by said boom and arranged receive material discharged from said buckets as they move around said upper sprockets and to convey the material toward said mast; hoist means supported by said mast for lifting and lowering said boom; and counterweight means supported by said mast and connected to said boom for counterbalancing the load on said boom.
Claim 3
Dependent Claim
61 words
The material handling apparatus as set forth in claim 1 wherein said upper sprocket has a larger diameter than said lower sprocket; and including idler wheel means supported at the upper region of said ladder frame for guiding said chain means such that the path profile of the chain means is one of general narrowing between the upper and lower sprockets.
Claim 4
Dependent Claim
65 words
The material handling apparatus as set forth in claim 2 including fixed roller support members arranged on said ladder frame and engaging said chain means for providing additional guide support therefor; and whereby said idler wheel means is supported for selective shifting with respect to said ladder frame such that said chain means may be selectively tightened and loosened with respect to said lower sprocket.
Claim 5
Dependent Claim
116 words
The material handling apparatus as set forth in claim 3 wherein said roller supports members disposed on the lower rear end portion of said ladder frame are arranged in such a position that when said idler wheel means is shifted for slackening said chain means, the path of travel of the chain means in the vicinity of said lower sprockets will be directed first away from said ladder frame and then toward it whereby said buckets would be dragged generally horizontally a short distance over the load being handled prior to beginning their upward travel around said lower sprockets and the leading edges of said buckets will move along the contour of the surface they encounter.
Claim 6
Dependent Claim
131 words
The material handling apparatus as set forth in claim 1 wherein said counterweight means includes a plurality of separate weight members pivotally coupled by links, the lowermost link being pivotally connected to said support mast at an intermediate position thereof; said counterweight means further including rope fall means and sheave means for connecting said weight members to said boom; said counterweight means being so arranged with respect to said support mast and said boom such that all of said weight members will act to counterbalance the load on said boom when said boom is in the generally horizontal position, and when said boom is raised the lowermost of said weight members will be supported by said mast while the upper of said weight members will counterbalance the load on said boom.
Claim 7
Dependent Claim
68 words
The material handling apparatus as set forth in claim 5 wherein said counterweight means is so constructed and arranged with respect to said support mast and said boom that the number of said weight members counterbalancing the load on said boom depends directly on the angle between said boom and said support mast so that as the angle decreases the number of weight members needed for counterbalancing decreases.
Claim 8
Dependent Claim
39 words
The material handling apparatus as set forth in claim 1 including an elongated hopper supported by said support mast and arranged for receiving material transported by said conveyOr means and for storing material prior to discharging the material therefrom.
Claim 9
Dependent Claim
44 words
The material handling apparatus as set forth in claim 7 wherein said hopper is sized to receive and store at least the entire quantity of material which would be on said conveyor means from the point of discharge of said buckets to said hopper.
Claim 10
Dependent Claim
66 words
The material handling apparatus as set forth in claim 1 including a discharge chute arranged between said conveyor means and the position of discharge of said buckets as they move around said upper sprockets; and further including a material flow divider fixed on said discharge chute for dividing the flow of material moving down the chute such that material is evenly distributed on said conveyor means.
Claim 11
Dependent Claim
144 words
The material handling apparatus as set forth in claim 1 wherein said buckets have a generally scoop shape with a rear portion deeper in depth than the forward portion thereof and tapering upwardly towards a generally sharp forward edge; said buckets being supported by said chain means such that the open top of the buckets are in planes generally normal to the chain means and the deep depth rear portions face rearwardly of said ladder frame when the buckets are disposed on the rearward side of the ladder frame and the rear portions of the buckets face forwardly when they are travelling upwardly on the forward side of said ladder frame, whereby material will be scooped up when the buckets are advanced around said lower sprockets and will discharge material from the forward ends thereof as the buckets are advanced around said upper sprockets.
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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) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |