US3653486A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Material handling apparatus
Assignee: Dravo Corp
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Filing: 1970-07-17
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Granted: 1972-04-04
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Expires: 1990-07-17
Abstract
Abstract There is shown a mobile material handling structure, such as a bucket wheel stacker and reclaimer having a carriage on which is a turntable structure comprising the turntable itself, with a mast, a load boom pivoted to swing in a vertical arc, and a counterweight at the end of a pivoted strut that extends out beyond the turntable in a direction diametrically opposite the load boom. A cable, connected with the counterweight, passes over the mast and is attached to the boom, so that as the boom swings up or down from a level position, the pivoted strut with its counterweight swings in an opposite direction from a level position. The center of mass of the counterweight is roughly about as far from the center of rotation of the table as the center of mass of the load boom so that the moment arms through which the two masses are effective to counterbalance each other are approximately equal at all times.
Inventors
- 👤 William B Mclean
- 👤 Laimons Naruns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:08
CPC Classifications
E; E02; E02F; E02F9/00; E02F9/18; B; B65; B65G; B65G65/00; B65G65/02; B65G65/16; B65G65/20; B66; B66C; B66C23/00; B66C23/62; B66C23/72; B66C2700/00; B66C2700/03; B66C2700/0392
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
144 words
In a material handling apparatus of the type having a carriage, a turntable assembly on the carriage comprising a turntable, a mast structure on the turntable, a load boom pivotally connected with the turntable for movement in a vertical arc and a hoisting drum and cable for raising and lowering the load boom, the invention comprising: a. a strut extending in a direction diametrically away from the boom pivotally connected at one end with a part of the turntable assembly for movement in a vertical arc, b. a counterweight on said strut, c. a second cable of fixed length fixedly connected at one end with said counterweight, and d. the mast structure having sheaves thereon over which the cable passes, the other end of the second cable being fixed to the load boom between its pivotal connection to the turntable and its working end.
Claim 2
Dependent Claim
144 words
In a material handling apparatus of the type having a carriage, a turntable assembly on the carriage comprising a turntable, a mast structure on the turntable, a load boom pivotally connected with the turntable for movement in a vertical arc and a hoisting drum and cable for raising and lowering the load boom, the invention comprising: a. a strut extending in a direction diametrically away from the boom pivotally connected at one end with a part of the turntable assembly for movement in a vertical arc, b. a counterweight on said strut, c. a second cable of fixed length fixedly connected at one end with said counterweight, and d. the mast structure having sheaves thereon over which the cable passes, the other end of the second cable being fixed to the load boom between its pivotal connection to the turntable and its working end.
Claim 3
Dependent Claim
46 words
The invention defined in claim 1 wherein the radial distance from the center of mass of the load boom to the axis of rotation of the turntable is at least roughly comparable to the distance from the center of mass of said counterweight to said axis.
Claim 4
Dependent Claim
41 words
The invention defined in claim 1 wherein the loadboom and the pivoted strut are arranged through said cable to move in substantially equal but opposite vertical arcs with respect to the horizontal when the load boom is being raised or lowered.
Claim 5
Dependent Claim
43 words
The invention defined in claim 1 wherein the pivoted strut with its counterweight are arranged to keep said cable taut at all times whether or not the free end of the boom is resting on the ground or on a stack of material.
Claim 6
Dependent Claim
31 words
The invention defined in claim 1 wherein the strut is pivotally attached to the mast at a level above the level where the load boom is pivotally attached to the turntable.
Claim 7
Dependent Claim
63 words
The invention defined in claim 1 wherein the apparatus is a stacker-reclaimer and the mast is a C-mast with a cantilever portion extending therefrom in a direction diametrically opposite the boom and said strut is pivotally attached to said cantilever portion and extends under said cantilever portion with its free end pointing in the direction of the free end of the cantilever structure.
Claim 8
Dependent Claim
24 words
The invention defined in claim 6 wherein the sheave for said cable is at the free end of the cantilever portion of the mast.
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) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-04 | 1979-10-04 | 1980-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-04 | 1983-10-04 | 1984-04-04 | $7700.00 | Window Closed / Lapsed |