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Title:
Stevedoring apparatus
United States Patent 2000054
Abstract:
This invention relates to the art of stevedoring vessels, particularly ocean freight carriers. With such vessels the cargo transported (excluding deck cargo) is stowed in the hold during transit and is both loaded and unloaded through the deck hatches. Practically all such vessels carry what...


Inventors:
Weeks, Francis H.
Publication Date:
05/07/1935
Assignee:
Weeks, Francis H.
Primary Class:
Other Classes:
212/74, 212/75, 212/77, 212/81, 212/257, 212/314, 414/138.7, 414/142.9, 414/143.1
International Classes:
B63B27/10
View Patent Images:
Description:

This invention relates to the art of stevedoring vessels, particularly ocean freight carriers.

With such vessels the cargo transported (excluding deck cargo) is stowed in the hold during transit and is both loaded and unloaded through the deck hatches. Practically all such vessels carry what is known as the "ship's gear" for stevedoring the cargo, comprising a mast adjacent the hatch, a boom connected to the mast near the base and extending therefrom over the hatch, together with the necessary engine and drum for operating cargo lifting means carried by the boom. This equipment is rather slow and awkward in use and the capacity per individual lift is not ordinarily high. In practice two booms are ordinarly employed, one extending over the hatch, and one extending over the dock or receiving vessel, and the draft is gradually shifted from one boom to the other. This is an improvement over the first procedure, but the sequence of steps involved renders the method relatively slow and a period of days is required to unload a ship. Every avoidable delay is objectionable owing to the great amount of capital represented by the ship which is inert during the unloading period. In harbors where the quantity of shipping renders it feasible, the unloading of such carriers is frequently accomplished by means of a barge supported crane which is moored alongside the ocean carrier.

The crane rotates as an entirety upon the barge, whereby the boom which projects adjacent the top of the crane can be brought either over the hatch of the freight carrier, or over the hatch or deck of the receiving vessel. Cranes of this type can be swung more rapidly than the ship's gear and usually have greater capacity per individual draft, but have the disadvantage that only part of the total number of hatches may be unloaded at a time owing to the space occupied by the barge support. Inasmuch, moreover, as the barge support occupies an intermediate position between the ocean freighter and the receiving vessel, the distance through which each draft of cargo must be moved is relatively greater than when using the ship's gear.

I have devised a new method of unloading ships, pursuant to which all hatches may be simultaneously unloaded with relatively greater speed and efficiency than is obtainable by either of the methods described. In accordance with my invention, I utilize cranes of such a type that one or more may be simultaneously applied to each hatch. Each cargo draft is moved through the minimum possible distance, and the receiving vessel may be moored directly alongside the ocean freighter. Inasmuch as the method is broadly new and not heretofore contemplated, it has been necessary for me to devise the instrumentality for this purpose. In general, the apparatus which I have devised for this purpose comprises a straight line unloader, viz, a rectilinear cargo beam carrying a trolley which moves longitudinally with respect to the beam, together with means supporting one end of the beam for distributing the transmitted load directly on to the deck on one side of the ship between the hatch and the outside rail, and together with driving means, drums, etc.; carried by the supporting means, thus constituting the entire apparatus, a self contained entity which may be lifted on to a steamship and immediately placed in operation. The other end of the cargo beam, viz, the end adjacent the other side of the ship, may rest directly upon the contiguous hatch coaming, but preferably suitable means is provided for distributing the transmitted load directly on to the other side of the ship on the deck between the hatch and the outside rail.

The span of the cargo beam between supports must be such that the device may be applied without alteration to the vast majority of ocean freighters, and the weight and proportions of the device must be such that it can be placed in position either by the ship's gear or by the use of a barge supported crane. Ordinarily, I prefer to supply the steamship to be unloaded with a sufficient number of these cranes to service every hatch. The cranes may, for example, be brought to the ship by means of a lighter. These cranes are then placed in their respective positions, viz, one or more cranes applied to each hatch, whereupon the lighter is withdrawn and the receiving vessel is placed alongside of the ocean freighter. If the freighter is moored alongside of a dock, the crane may be picked up directly from the dock by the use of the ship's gear and placed in operative position. _It then becomes immediately possible to unload each hatch simultaneously and each crane is individually capable of a much greater unloading rate than could be obtained either from a unit of the ship's gear or a barge supported crane. I am aware that straight line unloaders have been heretofore constructed as permanent and practically integral parts of the equipment of a particular ship. Such unloaders were, however, constructed exclusively to service a particular ship. They were not of such form and proportions as to permit of their application to ships in general or in fact to any ship excepting the particular one referred to, and were not in any way adapted to serve the purpose which I have disclosed. The subject matter of this application in part corresponds to that of prior application Serial No. 87,254, filed February 10, 1926.

The broad features of the apparatus which I have devised, together with the more specific features by means of which it has been particularly adapted to the service disclosed, will be apparent from the following description read in conjunction with the drawings, in which, Fig. 1 is a side view of an embodiment of my invention.

Fig. 2 is a section through the construction shown in Fig. 1, on the broken plane indicated by I-I.

Fig. 3 is a detailed side view of part of the construction shown in Fig. 1.

Fig. 4 is an end view of the construction shown in Fig. 3.

Fig. 5 is a perspective view of a part of the construction shown in Fig. 1.

Fig. 6 is a perspective view of a part of the construction shown in Fig. 1.

Fig. 7 is a side view with parts in section of part of the construction shown in Fig. 1.

Fig. 8 is a perspective view of another part of construction shown in Fig. 1.

Fig. 9 is a section through part of the construction shown in Pig. 1, on the plane indicated by II-II.

Referring now to Fig. 1, the device comprises rectilinear cargo beam I, preferably of the I beam type. The trolley 2 reciprocates longitudinally with respect to the beam I by means of the rollers 3 which ride on lower flange 4 of the beam I. The device as an entirety is adapted to be rested on the deck of a ship with the cargo beam I straddling the hatch. In Fig. 1, the deck has been indicated in outline.

The one side, for example, the port side of the hatch coaming may be designated by the numeral 10, and the corresponding side of the deck 5 between the hatch coaming and the outside rail of the ship may be designated by the numeral 12. The other or starboard side of the hatch coaming may be designated by the numeral 13, and the corresponding side of the deck beStween the hatch coaming and the outside rail 14 of the ship may be designated by the numeral 15. For reasons which will be hereinafter more fully pointed out, the cargo beam I is preferably oblique when the device is in working position. In this case the lower end 20 of the beam may be rested directly on the upper surface 10a of the hatch coaming 10 but is preferably supported by some appropriate means for distributing the transmitted weight of the device directly on to the deck of a ship.

This may consist of support 19, comprising stringers 21 and 22 secured to the plate 23 (Fig. 4) of U section. It will be noted that the plate 23 (Fig. 4) carries the rollers 30 and 31 which are connected to the plate by means of the pins 32 and 33'. When the device is in use, the upper flange 34 of the cargo beam I rests directly on the rollers 30 and 31. In consequence of this construction, the support 19 is not rigidly joined to beam I and is enabled to adjust itself to the thwartship slope or crown of the ship's deck. The support 19 is held in position by means of the removable pin 35 which abuts against the end 20 of the beam 76 I, which pin is passed through aligned apertures in plate 23. The transmitted weight of the other end of the cargo beam I is distributed over the ship's deck by means of the framework 40. This is a rigid stiffly braced upstanding framework of considerable cross-sectional area In the view shown in Fig. 1, it comprises the upstanding corner posts 41, 41a, 42 and 42a rigidly braced and interconnected by means of beams such as 43, 44 and 45. These are riveted or similarly connected to the corner posts. The lower surface of the framework 40, as will be noted from Fig. 6, is formed by the stringers 50', 51', 52', and 53', which define a roughly plane and substantially horizontal lower surface. In any event, the stringers 50' and 52' which extend longitudinally of the ship should be at least 6 feet in length so that the transmitted load will invariably rest on at least two of the deck beams such as 25 underlying the framework. It is frequently necessary to shift the device longitudinally for adjustment with respect to the hatch, and in all such cases it is advisable that the transmitted stress be carried by at least two of the underlying deck beams. Preferably, the lower surface of the framework 40 is of considerable cross-sectional area, and in addition to being at least 6 feet in length is at least 4 feet in width so that the framework is capable of standing securely alone when placed on the deck of a ship, notwithstanding the crown or camber of the ship's deck and notwithstanding the listing which frequently occurs. The necessary mechanism for operating the lifting apparatus consists of the motor 60" (Fig. 1), reduction gear 51 (Fig. 2), g and the drums 52 and 53 actuated from the reduction gear 51 through spur-gear 56 and controlled by means of the handles 54 and 54a.

The motor 60" continuously turns gear 56 through the reduction gear 51, and the spurgear 58 is continuously in mesh with a gear at one end of drum 53 and with a gear at one end of drum 52. The drums ordinarily idle while the corresponding gears turn but either or both drums may be caused to turn by ma- 4 nipulating handles 52 and 53 which control clutches placing the respective drums in operative engagement with the respective gears.

Such mechanism is usual equipment for hoisting drums and is not therefore set forth in detail. This mechanism is supported adjacent the base of the framework 40 by means of the beams 60' and 61' (Fig. 6). The width of hatch on the various ocean freighters varies within certain limits: I find, however, that I can service the great majority of all such freighters by the use of a crane in which the span or reach of the beam measured from the foot of the tower 40 is at least 18 feet, in case the lower end of the beam is to be rested directly on the hatch coaming 10a, or alternatively, in case the lower end of the beam is to be rested directly on the deck surface, the span or reach of the beam measured between the nearest points of the support 19 and the framework 40 is at least 16 feet; and for this reason the device should be at least capable of substantially this degree of span. Inasmuch, moreover, as the device must ordinarily be lifted on shipboard by means of the ship's gear or barge supported crane, its gross weight must be kept relatively low. In case the apparatus is to be placed in position on board of ship by means of a barge supported crane, the gross weight of the apparatus should not exceed 10 tons. In case the apparatus is to be placed in position either by means of a barge supported crane or by means of the ship's gear, the gross weight should not exceed 5 tons. Inasmuch, moreover, as there are frequently obstructions above the ship's deck, as for example masts, booms, bracing, rigging, aerial wires, etc.; it is highly advisable that the apparatus is susceptible of being placed in position by a barge crane, the boom of which does not extend to the middle of the freighter. In the preferred embodiment of my device, it is only necessary for the boom of the barge crane to reach over the side of the freighter for a distance of a few feet, thereby avoiding contact with any obstructions surmounting the ship's deck. This result is due to the fact that in my preferred construction the center of gravity of the device is well over to one side and adjacent the upstanding framework. The entire device may be lifted by a hook or sling connected to the framework or adjacent thereto. With the oblique beam illustrated in Fig. 1, it will be noted that the support 19 at the end 36 of the beam I is relatively low and of lesser weight than the framework 48. In addition, the driving means, drums, etc. in the base of the frame 40 tend to bring the center of gravity adjacent the framework, and the chute 46 further tends to place the center of gravity of the device at or adjacent to the framework 40. With the form of device illustrated in Fig. 1, moreover, in which the beam I is not rigidly connected to the framework, but is freely suspended therefrom, it is of further specific advantage that the beam can be itself substantially balanced with respect to the point 61 of attachment to the framework 40. It will be noted that the end 60 of the beam I which end is remote from end 36 extends beyond the point 61 of attachment to the frame 40. The trolley 2 and the bucket 63 suspended therefrom may be drawn up adjacent the end 60 by operation of the drums 52 and 53, thereby assisting to balance the beam I with respect to the point 61. The 42 bucket shown is of the single line type in which the elevation and opening of the bucket are effected by means of a single cable. It will of course be understood that a two line bucket may be employed if desired in which event a 50 third drum will be required in the base of the framework 40 to manipulate the extra line.

The trolley 2 also carries a hook-eye 64 which may be connected to the hook 65 carried by the support 19 by means of a link or short Scable. By connecting the trolley and support 10 together, and removing the pin 35, the trolley, bucket and support may be together drawn up and suspended from the section 62 of the beam 1, thereby placing the entire beam in 60 substantial balance with respect to the point 61. As a consequence of this, as the crane is being placed in position, the end 36 of the beam I requires no especial support and may be easily guided into position athwart the hatch by a man standing on the deck portion 12.

Owing to the general arrangement of parts, moreover, the beam I may be easily inserted under the rigging or obstructions surmounting the hatch. The beam 1 is carried by the shoe 70 (Fig. 5) composed of the sections 71 and 72, defining the slots 73 and 74, respectively, which grasp the flange 34 of the beam 1. The shoe 70 is held firmly in engagement with the flange 34 by means of bolts 75 and 76, threaded through the aligned apertures 77, 77a, 78 and 78a, respectively. By loosening the bolts, the beam may be adjusted longitudinally with respect to the shoe 7D, and in this manner the device is made adjustable so that it will, without alteration, fit the occasional ship equipped with exceptionally wide hatches. It will be noted (Fig. 2) that the cables O1 and 113 from the drums 53 and 82, respectively, pass over the pulleys I 1 and ! 4 and thence through the pulleys i12 and i5. Cable I13 passes from pulley 115 to the pulley Ig adjacent the end of the beam, and returns thence to the trolley 2. The cable I 0 passes from the pulley I12 to a pulley positioned similar to the pulley 116 but on the opposite side of the beam I, and returns thence to the pulleys 1i7, Ila and I18 by means of which the bucket I19 is manipulated. Inasmuch as the pulleys 112 and i15 are carried by the portions 71 and 72 of the shoe 70, it will be noted that these pulleys are not affected by movement of the beam I longitudinally with respect to the shoe 70 for the purpose of altering the reach of the beam.

The shoe 70 which carries the beam I, etc. is in turn suspended from a bolt 80, threaded through the aligned apertures 81 and 81 . The bolt 80 is carried by the eye 82 (Fig. 7 and 8) which preferably loosely engages the bolt 80 so that the vertical angle of the beam with respect to the framework 40 is not fixed, and the device therefore adapts itself automatically to decks with differing degrees of crown. The eye 82 is connected with the eye 83 by means of a swivel 82. The eye 83 is in turn suspended from the clevis 84. The clevis 84 is detachably carried by the bar 85 connected by the bolt 90 to the cross-bar 92. Inasmuch as the eye 82 is rotatable through swivel 82a with respect to eye 83, the end 36 of the beam I may be moved through a wide angle with respect to the frame 40. In the operation of the device, therefore, it is not frequently necessary to move the framework 40 with respect to the hatch, but the end 36 of the beam I may be moved through a horizontal angle without movement of the framework 40, thereby permitting the device to service the major part of the space beneath any particular hatch.

Moreover, by running the trolley 2 and support 19 up to the section 62 of the beam I, the 50 beam is brought substantially in balance so that it can be swung through a horizontal angle by a single operator if desired. Owing to the rigorous limitation as regards weight hereinbefore noted, it is not possible to build the beam 55 1 with an extremely high factor of safety. In meeting the weight limitation a factor of from 2 to 3 is about all that can ordinarily be provided. It is necessary, therefore, to avoid subjecting beam I to side stresses. In picking up cargo in various parts of the hold, the stress is not always or even usually vertically beneath the beam 1, but is ordinarily applied from one side; and with the ordinary type of beam would apply a twisting stress which would exceed the factor of safety of the beam. With my form of construction, however, the beam can turn through a dihedral angle traverse to clevis 84 and can face the load regardless of the point from which it is applied. This is possible due to the mode of attachment of eye 83 to the clevis 84 and is further rendered possible by the fact that the rollers 30 and 31 do not actually engage the web ia of the beam I (Fig. 4) so that considerable angular movement of the beam I is possible. A connection such as described in this paragraph, whereby the beam may be moved through a vertical angle with respect to the framework to adapt the device to decks with differing degrees of crown, and whereby the beam may be moved through a horizontal angle with respect to the framework, thereby permitting the device to service the major part of the space beneath the hatch without changing the position of the framework, may be hereinafter referred to as a "universal connection." In operation with a grab bucket and bulk cargo the bucket dumps into hopper 46 which communicates with chute 46a. The chute may discharge directly into a lighter or barge positioned alongside the freighter, or for ship to shore unloading may discharge on to a belt conveyor or the like. The foregoing specific description is intended by way of illustration and not of limitation. It is therefore my intention that the invention be limited only by the appended claims or their equivalents in which I have endeavorcd to claim broadly all inherent novelty.

I claim: 1. A crane for stevedoring vessels of a size and weight adapted to be removably applied to the deck of the usual freight carrying vessel without alteration of said deck, said crane being of a self-contained operating unit adapted to be immediately operated when so applied, said crane including a rigid stiffly braced selfsustaining and upstanding tower, terminating in a substantially horizontal plane lower surface, said tower being of a size adapted to be rested directly on the deck of the usual cargo carrying vessel in the space between the hatch coaming and the adjacent side of the ship and being of a weight adapted to be carried by the deck of the usual cargo carrying vessel between the hatch coaming and the adjacent side of the ship, said crane comprising in addition a cargo beam suspended from said tower adapted to extend therefrom transversely across the hatch of the usual cargo carrying vessel and to be supported by the side of said vessel remote from the said tower, a trolley carried by and movable longitudinally along said beam, driving means connected to and carried by said tower, drums operatively connected to said driving means, said driving means, drums and said trolley being operatively connected to lift cargo out of the hold of the ship and to move same longitudinally along the said beam.

2. A crane according to claim 1, in which the length of the said beam is adjustable with respect to the said tower.

3. A crane according to claim 1, in which the cargo beam is suspended from said tower by a universal connection. FRANCIS H. WEEKS.