US 3042222 A
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Description (OCR text may contain errors)
July 3, 1962 G. w. LEHMANN CARGO BOOM 3 Sheets-Sheet 2 Filed April 15, 1959 FIG. 3
l/V VEA/TOR GLUE/V7795? w LEf/MA NM ML m. MEMO AGE/VT July 3, 1962 G. w. LEHMANN CARGO BOOM 3 Sheets-Sheet 3 Filed April 15, 1959 United States Patent Ofilice 3,042,222 Patented July 3, 19 32 Honolulu, Hawaii Filed Apr. 13, 1959, Ser. No. 806,124 8 Claims. (Cl. 212-3) The present invention relates to improvements in cargo hoisting means and, more particularly, to a cargo boom mounted on a ship and adapted to serve more than one hatch.
There have been increasing demands for heavy lift rigs on freighters for hoisting individual heavy loads into and out of the cargo space. Such heavy lift gear requires a heavy boom in conjunction with heavy and expensive winches and auxiliary equipment. If such heavy cargo booms serve only a single hatch, the operation is highly uneconomical since it requires separate expensive hoisting equipment for each hatch.
In an effort to increase the efficiency of heavy topping lift equipment aboard ships, it has been proposed to mount a single heavy boom between two kingposts erected between two adjacent hatches and to swing the boom through the kingposts from one hatch to the other. However, the known equipment of this type has required special means for shifting the blocks of the hoist gear, dismantling and reassembly of the hoisting leads, blocks and other rig parts, all of which involves a Waste of time and increases the unproductive harbor days of a freighter.
It is the principal object of the present invention to overcome the latter disadvantages and to produce a cargo boom which can be swung between adjacent hatches without special shifting devices or dismantling of any parts.
The boom according to the present invention resembles a gallows and has two legs through which the hoisting gear may freely swing when the boom is pivoted between two kingposts to extend over respective ones of adjacent hatches. According to one feature of the present invention, a crosspiece is mounted between the boom legs at their top to support an upper hoisting block or its links, sufficient clearance being provided between the legs to permit the upper and lower hoisting blocks of the hoisting gear to pass therethrough to extend on one or the other side of the boom. The hoisting leads are so arranged on the blocks and their drums that they remain thereon during the shifting-over and in no way interfere with the blocks or with the hoisting leadlines while the position of the boom is changed from one hatch to the other.
In accordance with another feature of this invention, the topping lift blocks for lowering and raising the boom are secured respectively to the tops of the two kingposts and to the upper ends of the gallows boom. The lift blocks which are attached to the kingposts are self-adjusting to any direction in which the boom may be positioned by providing a universal mounting of the blocks on the kingposts. This mounting may take the form of a ring supported on the kingposts by means of roller bearings and provided with a lug for the attachment of the topping lift blocks. In this manner, the lift blocks may freely follow any movement of the gallows boom.
According to another feature of the present invention, the boom is pivoted to an oscillatory turntable which also carries the winches for the hoisting gear and for raising and lowering the boom. In this arrangement, the hoisting and lifting ropes always remain on their dmms and blocks, regardless of the working position of the gallows boom, only one set of winches being re quired for operation of the boom over two adjacent hatches. The hoisting leadlines are attached to the sides of the hoisting blocks and positioned close to each leg of the gallows boom on their passage to the winches on the turntable so that the blocks may freely pass through the legs when the boom is shifted from one hatch to the other. The topping lift leadlines are attached to the top of the legs at their outsides so that they never interfere with the hoisting leadlines, regardless of the position of the boom.
The boom is lifted and eventually turned from one hatch to the other by adjusting the length of the topping lift leadlines. If the length of the two topping lift leadlines is varied independently from each other, the elevation and the outreach of the boom will be adjusted in any desired position. Actuation of one or the other topping lift leadline produces a pull on the boom which will be translated into a turning moment on the turntable so that the latter requires no separate drive for oscillation. The turntable, which supports the boom and its winches, turns automatically under the influence of the shortening and corresponding slackening of the two lifting leadlines.
The above and other features of the present invention will be more fully described in the following dctailed description of a preferred embodiment, taken in conjunction with the accompanying drawing wherein FIG. 1 is a side elevation of the cargo boom and showing the single boom positioned in opposite, alternative directions;
FIG. 2 is a top view of the boom;
FIG. 3 is a front view of the boom during the operation of shifting it from one hatch to the other; and
FIG. 4 is a side view of a freighter with two cargo booms serving four hatches.
Referring now to FIGS. 1 to 3, the gallows boom 1 is shown to have two legs 1a and 1b pivoted on turntable 3- by brackets 2a and 2b. Deckhouse 10 carries pivot 4 for oscillatory support of the turntable and ring 5 for maintaining the turntable in horizontal position during its rotation. Kingposts 11 and 12 are mounted at the respective ends of the deckhouse and carry on top rings 13 to which the upper topping lift blocks 15 of the boom 1 are attached. Rings 13 are freely rotatably mounted on the kingposts, for instance, by means of roller bearings, and have lugs 14 which permit the blocks 15 to be secured to the rings.
As best shown in FIGS. 2 and 3, a crosspiece 16 interconnects the upper ends of legs 1a and 1b and serves to support the upper hoisting block 17 or link supports for the upper hoisting block. Topping lift blocks 18 and 19 are attached to the outsides of the boom legs at or near their upper ends.
The hoisting gear 23 is mounted on the upper hoisting block 17 and carries lower hoisting block 22, the entire hoisting assembly being accommodated between the boom legs and free to swing therethrough when the boom is shifted over from hatch 20 to hatch 21, or vice versa. Hoisting Winches 6 and 7 are so arranged on the turntable that the hoisting leadlines 24 and 25 are close to the insides of the boom legs, leaving ample clearance for passage of the hoisting gear 23 with blocks 17 and 22.
When the boom is to be shifted from one hatch to the other, topping lift leadlines 26, 27 will first be shortened by operating lifting Winches 8 and 9. After the boom passes between the kingposts, the topping lift leadlines will be slackened again until the boom has reached the desired position over the other hatch. The dead point of the boom, when it is in a vertical or nearly vertical position, may be overcome by applying a special rope pull on book 28 of block 22 or by any other suitable means which will push or pull the boom across the dead point.
It is obvious from the above description that the boom of the present invention may be shifted from hatch to hatch without disconnecting any ropes or dismantling any parts, the boom being immediately ready for a loading or unloading operation upon completion of the shifting.
independent operation of winches 8 and 9 results in a selective slackening and/or shortening of leadlines 26 and 27 with a corresponding change in the position of boom ll.
Additional deck space close to the deckhouse may be provided by mounting the kingposts ll, 12 with an upward slope, as shown by lines 35 and 36 in FIG. 3, the lower ends of the kingposts being closer together while their tops are spread apart to permit swinging of the gallows boom over the side as far as possible.
The axes 37 of the hoist blocks 17 and 22 are transverse to the plane defined by the boom legs to prevent jamming of the hoisting leadlines 24, 25 with the hoisting gear 23 and to direct the hoisting leadlines properly to the winches in either location of the boom 1 over hatch 2% or hatch 21. This is contrary to the conventional arrangement wherein the axes of the hoisting blocks are transverse to the axis of the boom.
FIG. 4 schematically shows a cargo ship with four hatches 33, 32, 33, 34 and two heavy lift rigs 29, 30 mounted between ad acent hatches.
The gallows boom has been described and illustrated with the winches mounted on a turntable with the boom. However, it may also be used in combination with winches mounted on a fixed platform. In thi case, cheek blocks are required to direct the hoist and lift leadlines properly on the winches.
While the invention has been described in connection with a single embodiment, it will be obvious that many changes and modifications in structural details may occur to the skilled in the art, particularly after benefiting from the present teaching, without departing from the spirit and scope of the invention as defined in the appended claims.
1. A cargo lift gear comprising two kingposts, a boom consisting of two legs, pivotal bearing means connected to the lower ends of the boom legs and mounting the boom for pivotal movement between said kingposts, and to either side of the plane defined by the kingposts, a loadbearing crosspiece connecting the upper ends of the boom legs, a hoisting gear including upper and lower hoisting block means, the upper hoisting block means being supported by said crosspiece substantially midway between the boom legs and the two boom legs defining an unobstructed clearance to permit the hoisting gear to pass between the legs, and topping lift blocks attached to the upper ends of the boom legs at their outsides and to the kingposts for controlling the position of the boom.
2. A cargo lift gear comprising two kingposts, a boom consisting of two legs, pivotal bearing means connected to the lower ends of the boom legs and mounting the boom for pivotal movement between said kingposts and to either side of the plane defined by the kingposts, a hoisting gear including upper and lower hoisting block means, a load-bearing crosspiece connecting the upper ends of the boom legs and supporting the upper hoisting block means substantially midway between the boom legs, the two boom legs defining an unobstructed clearance to permit the hoisting gear to pass between the legs, first winch means in alignment with the boom, hoisting leadlines wound on the winch means and attached to the upper hoisting block means for lowering and raising the hoisting gear upon operation of the winch means, the hoisting leadlines being arrangedbetween the boom legs and the hoisting gear to leave said clearance unobstructed, topping lift means including topping lift block means attached respectively to the outsides of the upper ends of the boom legs and to the upper ends of the kingposts, second winch means mounted adjacent and outside the boom legs and topping lift leadlines wound on the second winch means and attached to the topping lift blocks which are attached to the upper ends of the boom legs for raising and positioning the boom upon operation of the second winch means.
3. The cargo lift gear of claim 2, further comprising a turntable freely rotatably mounted for oscillatory move ment between the kingposts and carrying the pivotal bearing means for the boom legs and the winch means.
4. The cargo lift gear of claim 3, comprising universally mounted means for attaching the topping lift block means to the upper ends of the kingposts.
5. The cargo lift gear of claim 2, wherein the axes of the hoisting block means are transverse to the plane defined by the boom legs.
6. The cargo lift gear of claim 2, further comprising a turntable freely rotatably mounted for oscillatory movement between the kingposts and carrying the pivotal bearing means for the boom legs and the winch means, the second winch means consisting of two independent winches positioned at each side of the boom.
7. A cargo lift gear comprising a boom consisting of two legs and a load-bearing crosspiece connecting the upper ends of the boom legs, an oscillatory turntable pivotally mounting the boom, a hoisting gear mounted on the crosspiece of the boom, a topping lift means attached to the upper end of the boom and to two fixed points, respectively, said two fixed points and the pivotal mounting of the boom defining a plane, hoisting winches and topping lift winches mounted on the turntable, hoisting leadlines wound on the hoisting winches and attached to the hoisting gear, topping lift leadlines wound on the lifting winches and attached to the topping lift means, the winches being so positioned that the hoisting and lifting leadlines do not interfere with each other during positioning movement of the boom, the turntable being oscillated automatically upon independent operation of respective ones of said lift winches to shorten one of said topping lift leadlines while the other one is correspondingly slackened, and the hoisting leadlines being so attached to the'hoisting winches that they emerge from the lower side of the winches when the boom is pivoted to one side while they come from the upper side of the winches when the boom is pivoted to the opposite side.
8. A cargo lift gear comprising two kingposts, a boom between said kingposts, a turntable pivotally mounting the boom and mounted for free oscillation between the kingposts, topping lift block means attached respectively to the boom and to each of the said kingposts, and winch means including topping lift leadlines attached to the topping lift blocks for raising the boom and for oscillating the turntable so as to position the boom upon operation of the winch means.
References Cited in the file of this patent UNITED STATES PATENTS 2,562,086 Farrell July 24, 1951 FOREIGN PATENTS 766,718 Great Britain Ian. 23, 1957