US2473039A - Composite ship construction - Google Patents

Description

June 14, 1949., R. c. SABINS COMPOSITE SP IIP CONSTRUCTION Filed July 1, 1944 m w a \...2 r $988 1 Patented June 14, 1949 UNITED STATES" PATENT OF Fl CE.

2,,4 ;1s,03a COMPOSITE. SHIP CON STRUCTIQN Rolland; Sabins, Seattle Wash. Application. July 1', 1944, Serial No. 5313;106

18-:Cl'aims-. (o1. ni -65.);

I Myinvention relates to vessel construction, and more particularly to the prefabricated construction of fore and aft parts of smaller" boats.

Except perhaps fcr bo'atsfof a length less than about twenty feet it'has' been the practicehere-- the same general type, although theymay-vary somewhat in size and shape.

In hull construction themost difiicult portions tofabricate have been those which have surfaces ofcompound curvature between thekeel' and the gunwale. This is particularly true of the sternportion of theship, and to a lesser extentof the bow. Between these portions: the sides ot a tugboat or fishing boat, for example, of forty to.

one hundred feet: in length. are of single convex:

curvature. At: the. stern,. however; the. upper por tionof the. side is. of convex. external curvature; while the lower portion is concave. At the bow; on the contrary; the upper portions; of" the sides frequently are; somewhat" concave, while thelower portions. are. convex.

It is: therefore more particularly an object of my invention. to provide. prefiabricated stern and bow portions: intendedespecially tor incorpora, tion in boats oi medium. size, such as forty to one hundred; feet. in length, although the sameprinciples may be: employed: for smaller or larger vessels.

It is: a further object ofmy invention to. make such prefabricated sections, of rugged construe,

ti'on, and to: arrange such sections. for convenient;

and secure attachment to. elements of the inter-- mediate. boat: structure conventionally employed.

Another object is to utilize the space within such: prefabricated sections for cargo. space, and

more. particularlyto; forln them. as: tanks for helm or fiueli, or. water ins: liquid, whether oil. for: for ballast or ion use; aboartii shim.

Still an additional object: is. to incorporate in. the. prefabricated. stern. section mounting: fixtures;

5 other; advantages gran invention. willhe;

- 50. hic usually-marine considerable labor and. skill pointed out in connection with the following description of the construction which I now prefer.

Figure 1- is a sideelevationview of a representative type ofboat incorporating prefabricated ti'on.

Figure: 2 is an athwartsh-ips sectional view through the stern prefabricated section taken along line 22 of'Fig-ure 1'.

bow: and stem sections according to my inven- Figure 3 isan athwartships sectional view througl rv the bow 3'-3* of Figure 1.

Figure 4 is a fragmentary horizontal sectional view at line 4--4-of'Flgure I illustrating the-interprei abricated, section on line,

a connection of the' stern prefabricated section with the midshipsection, whi'chlatter section maybe of conventional boat structure; intermediate the bow and stern prefabricated sections. Figure 5 is a fragmentarydetail sectional view on line- 5'5 of Figure 1 showing theinterconnection between thesternof the bow prefabricated sectionand the conventional stem post.

Boats of the size, and type for which my structure is most useful are usually 'made'of wood, in- 5 cluding upright wooden frames or ribs secured I together by-a solid wall of planks running fore and aft. At the stern oftheboat the frames were of compound curvature. having an upper portion of convex outer contour and a lower por- 1 tion of concavev outer contour; attaching the planks to such framesit was: necessary not only to bend: them inward? around the stern, but also to. twist: or warp their: contour from the convex. shape of the. lower portion of the, hull amidshipsi tothe'concaveshape at the stern It was there-' fore difiicult both to shape the frames to the desired compound curvature and to. warp the planking. The same considerations apply in lesser degree toconstruction of thebow. Consequently the. fabrication; of these stern and bow portions: from wood required much more. labor and skill than other parts ofthe hull of comparable surface area...

My invention, thereiorez. contemplates the, prefabrication ofthese, complicated bow and stem. sections. as standard: parts, which are connected together bu an intermediate or midship; section. For different boats. such midship sections maybe;

of different; lengths: or of: diiierent:- maximum beam, within-1 limits;,-dependi-ng upon the length,.

capacity, and. general. design of boat required. This midship portion of the heat. can. be: of conventional: wood. structure having; substantially convex sides; that its construction; will not. be

'describeclin: greater: detail than necessary to in.-..

dicate the manner in which it is integrated with my prefabricated sections.

As shown in Figure 3, the upper portion of the bow is usually somewhat concave exteriorly, and consequently the frames or ribs I must be bent as shown. They need not be of compound curvature, however, because the lower portion of the bow is formed by the prefabricated bow section 2 of my invention. I prefer that this prefabricated bow section constitute a storage tank, which, for example, may be used to hold drinking water or water for the ships boilers. event, however, it will be hollow, and will have a top plate 20 and internal intersecting partitions, such as the central fore and aft baffle plate 2|, and the athwartships baflie plate or plates 22. These baflie plates are welded or otherwise made integral with the top plate 20 and the sides of the section 2, but if the prefabricated section is to be used for a storage tank some or all of such plates should terminate above the bottom of the section, as shown in Figure 3,. to afford intercommunication between the compartments. If it were desired to store different types of liquid in the bow section, however, one or more of the baffie plates could extend to the bottom of the section, and be welded to it, to form partitions separating the compartments.

It will be understood, of course, that th walls of the tank form the exterior of the bow section, and that no planking covers it. I prefer that this prefabricated section extend above the water line, as shown in Figure 1, and it will be made of fairly heavy steel plate, so that, particularly when stiffened by the partitions 2| and 22, it can withstand quite heavy impacts from floating logs, ice, or other objects which the boat may strike, without being injured. Even if the tank structure should be ruptured by such an impact the seaworthiness of the boat would not be greatly affected adversely, because the tank is sealed from communication with the rest of the hold, and consequently the only loss would be of liquid which might be stored in the tank section.

In order to withstand head-on impacts to even better advantage, the prefabricated section 2 has a solid stem strip or bar 23 of metal, which preferably extends from substantially the bottom of the keel or false keel l upwardly to the top of the planking. Above the tank portion of the prefabricated section this stem bar may be secured to the stem post I l by bolts or equivalent securing members 24 extending into or completely through them. As usual, the sides of the stem post are rabbeted to receive the forward ends of the planks I2 flush with the front portion of such post, and such plank ends are secured to the post in conventional fashion.

To the bottom of the prefabricated tank section is welded or otherwise integrally secured the upper flange of a T-bar or I-beam member 25 having the lower edge of its web similarly secured to the stem bar 23. A flange plate 26 is likewise welded to the lower edge of the aft portion of such members web, which is beveled upwardly and rearwardly so that such plate forms one element of a scarf joint between my prefabricated section and the keel or false keel i0. Bolts 21 extending through the complementally scarfed fore portion of the keel or false keel I0 and at least the lower flange plate 26 secure the aft portion of my prefabricated bow unit to the intermediate boat section of wood construction.

Such bolts may also extend through the upper flange of member 25, if desired, as shown.- After' In any the parts have thus been joined the channels between the upper flange of member 25, flange plate 26, and stem bar 23 may be filled with a suitable composition 28, such as concrete, as shown in Figure 3, so that the sides of this portion of the unit will be flush with the sides of the keel or false keel H].

To complete the attachment of conventional frame members to my prefabricated bow section angle brackets or bars 29 may be welded, or secured in an equivalent manner, to the top plate 20 at locations spaced inwardly from the outer walls sufiiciently to accommodate the frames I and planking l2. Before the planking is applied to the frames their lower ends will be bolted to these bars or brackets in the manner indicated in Figure 3. The forward ends of the planks below the top plate 20 of the unit 2 will be attached directly to the aft portion of the tank in a manner similar to the connection between the aft ends of such planks and the stern tank section, as illustrated in Figure 4 and as will be described in detail hereafter.

The stern prefabricated section 3 is larger and of considerably more complicated shape than the bow section described above. The sides of the stern section are of compound curvature, as shown in Figure 2, having an upper part of convex exterior shape and a lower part which is concave while portions of the central wooden hull midship section adjacent to the forward terminus of such stern section are of substantially simple convex curvature. Aside from such difference in shape, however, the structural elements and features correspond generally to the bow section.

Thus the top of the stern section is closed by a plate 30, and it is stiffened interiorly by a central fore and aft partition 3| and one or more athwartships partitions 32, serving as baiiie plates. While these partitions again have been shown spaced from the bottom of the section to afford intercommunication between the several compartments, if the unit is used as a. storage tank in the manner intended, one or more of these partitions may extend to the bottom of the unit to divide it into separate compartments. This unit may be used to carry fuel oil for the boats engines. if desired.

To accommodate the propeller shaft l3 a tube 3| may be carried by the lower edge of the fore and aft partition 3|. This tube will be sealed to the fore and aft tank walls, so that the propeller shaft may extend completely through the tank without coming into contact with its contents. Moreover this tube, or the aft wall of the tank adjacent to it, affords a sufficiently rigid structure to support the propeller shaft bearing 14. A stuffing box for the propeller shaft may be provided ahead of the tank units forward wall, since water filling tube 3| is sealed from the interior of the unit. Alternatively the stuffing box may be behind the aft wall of the unit.

In order to support the rudder a bar 33, preferably of inverted T-section, extends aft from the bottom of the stern unit, and terminates in a bearing for the lower end of the rudder post l5. Additionallya bracket 34 is mounted upon the upper aft portion of' the unit 3 to constitute an upper bearing for-the rudder post. An upright tube may extend through the tank incontinuation of this bracket 34 to accommodate the steering post extending upwardly above top plate 30.

To the bottom of the unit 3 is welded an element 35 of structural shape, preferably of I-beam section, extending a considerable distance ahead of the forward wall. of the-unit. Thezforerportiom ofits. web. is. cut.- on an upward. and forward. slope, and. a; flange plate 3.6 is. welded to it, to; constitute one-element; of. a scarf. joint. The aft, end. of the keet or false keell-llis complem-entalb scarfedi to fit against flange plate 3.6. and bolts; 37 pass. through. the keel. member Ill. and; at least flange: plate 36, although they may continue through the upper flange.- of? member 35., as. shown, to complete. the joint. The channel spaces at ortposite sides of the I-bcanr web,. and. between, the; upper I-beam. flange and; flange; plate; 36,, are then filled with concrete. 3.8 or similar materiah so. that the sides, of this. structure; also will. be flush with the; sides of; the: keel. or false keel; t;

Above.- top-v plate of. the stern unit; 3 horse:- shoe.- frames its may be placed. The lowermost; frame will be securedto the; metal unit 3; by" bolts welded to the top p1ate130 0f suchunit, andithe. superposed frames will then: be held together in conventional fashion to. form, the: stern bulwarks. Itwill be noted, however; that all: these frames are:- abovethe; bilge portionof. the. stern. section, so; that: their; exterior vertical. curvature, if any, is Slight;

Theends of the planks [52' adjacent to the. forward end of. stem, unit 3. and. the aft: end of how unit 2 are secured directly to these. units in. the manner shown in Figure 4-.. A bracket is welded to the; tank end wall, which. in this instance is the. forward wall of tank 3, although the:- arrange.- ment. would be. the same if it were the aft wall. of bow tank 2. These brackets are then bolted to the; ends of bilge stringers: I! which are secured in the normal way to frames t. In ad d-itionabar is. secured to or formed as a flange. integrally with the tanks end wall at. a location. spaced inward from the sides of the tank a dis tance equal to the thickness of. the planking [2. Preferably this bar extendsupward a substan-. tial distance above the top of the prefabricated: unit, and. may project clear to the: upper edge of the side to. form one of the. rib. or frame members. The ends of the planks: then overlap.- these. flanges 40 alongside the tank; and the planks will be bolted directly to these bars along their entire length. The. exterior of the planking will thus lie flush with the exterior of the tank sides. Calking material 41. maybe wedged between the ends of the planks and the tank, as shown in Figure 4, in the same manner that the cracks betweenadjacent planks. are calked.

The remainder of the boat construction is conventional, the deck. I8, for example, being supported above the top plate of the bow and stern tank units by deck beams: Hi; If desired, however,v one or. both of these prefabricated bow and stern sections. may extend to. a height such that the deck is supported directly upon top plates 20 and. 30; or they may even form part of the deck. Conversely, the. heights. of these. sections may be less than illustrated in Figures 2 and 3, but preferably they are of approximately the height shown.

Similarly the bow and stem sections may extend farther aft or farther forward, respectively, than shown in Figure 1, but it is preferred that the fore and aft extent be at least as much as shown, so that they will extend over the portions of the hull which are most difficult to fabricate from wood,

because of their compound curvatures.

It is not considered necessary to discuss in detail the operations adapted for prefabricating the units 2 and 3 since the technique employed would follow conventional metal tank and metal hull 6 manufacturing practice. Preferably the; exterior plates would: be bent. to shape. in jigs and the various elements would; then be welded together. Various methods. of constructing such hollow tank structures. of complicated shape. are. well known. to. people familiar with this field.

I. claim as. my invention:

12. A boat: hull comprising: a. hollow metal stern hnllzbottom portion, a. hollow metal bow hull bot-. tom. portion, a wooden hul-lportion between said stem portion and said bowhulle portion, and further extending from. stem to: stem ofthe. hull above said; metal stern and bow hull bottom por t-ions, and means: securing said: central wooden hull. portion to said metal stern and bow hull porti'ons: so that. the exterior surfaces. of said metal hull; portions and said central hull portion conjnintly form: a smoothhull contour.

2; A- boat hull: comprising a hollow metal stern hull bottom portion having a metal structural member secured to its bottom and extending for ward therefrom, a hollow metal bow hull bottom portion having a metal structural member socured to its bottom and extending aft therefrom, a keeli member having. its aft end rigidly'secured to. the f orwardf projecting end of the metal structural member of said stern hull portion, and having its forward:- end rigidly secured to the aft projecting end of said bow hull portion structural membena wooden hull 'portion between said stern hull-portion and said bow hull portion, and means securing said central woodenhull portion to said metal stern and bow hull portions.

3. A boat hull comprisinga hollow metal stern hull bottom portion having a metal structural member secured to its bottom and extending for ward therefrom to form an end beveled rearward ly and downwardly, a hollow metal bow hull bottom portion; having a metal structural member secured toits bottom and extending aft therefrom to form an end beveled forwardly and downwardly, a keel member having its aftend rigidly secured, by an end scarf joint to the forward, pro.-

Jectin beveled end of the metal structural member of said; stern hull portion, and having its. forward end. rigidly secured by anend scarf. joint.

tothe aft.- projeoting beveled end. of said bow hull, portion. structural. member, a wooden hull. portion, and. further. extending from stem to.- stern of the hull. above. said metal stern and bow hull bottom portions, and means securing said;

central wooden hull portion to. said and bow hull portions.

4.. Ahollow' metal exteriorly conforming to. an exterior bottom porti-o-n of a, boat. hull, and a metal. bar integral with said unit and extending upwardly a, substantial distance the-reabove, adapted to be secured at. spaced. locations along,- its length to a portion of a boat hull above such unit.

5. A hollow metal prefabricated unit having an exterior shape conforming to a portion of a boat hull and terminating at one end thereof in upright edges spaced apart transversely of the hull, and a metal member of structural shape secured to the bottom of such unit and having an end portion projecting lengthwise a substantial distance beyond said upright edges at one end of such unit, said end portion being adapted to be secured to a boat keel member.

6. A hollow metal prefabricated unit having an exterior shape conforming to a portion of a boat hull, and a metal member of structural shape metal. stern hull; por tion, between. said. stern hull portion and. said bowprefabricated unit of a shape-- secured to the bottom of such unit and having an end portion projecting lengthwise beyond such unit, said end portion being beveled to be secured to a boat keel member by an end scarf joint.

7. A metal tank unit of a shape conforming to the bottom bow portion of a boat hull, and a metal stem bar integral with said unit and extending upwardly a substantial distance thereabove, adapted to be secured at spaced locations along its length to the stem portion of a boat hull above such unit.

- 8. A hollow metal unit of a shape exteriorly conforming to the stern bottom portion of a boat hull, a metal member of structural shape secured to the bottom of such unit and having its aft end projecting aft therebeyond, a rudder post journal element carried by the aft end of said structural member, and an upper rudder post supporting element secured to the rearward portion of such unit above said lower rudder post journal element.

9. A hollow metal unit of a shape exteriorly conforming to the stern bottom portion of a boat hull, a metal member of structural shape secured to the bottom of such unit and having its aft end projectin aft therebeyond, and a rudder post journal element carried by the aft end of said structural member, the forward end of said structural member projecting forward beyond such unit and being adapted to be secured to a boat keel member.

10. A metal tank unit for a boat having an exterior shape conforming to the shape of the stern bottom portion of a boat including upper convex and lower concave side portions exteriorly, and a tube extending fore and aft through the bottom portion of such unit for reception of a propeller shaft.

11. A metal tank unit for a boat having an exterior shape conforming to the shape of the stern bottom portion of a boat including upper convex and lower concave side portions exteriorly, a tube extending fore and aft through the bottom portion of such unit for reception of a propeller shaft, and an upright tube extending through the aft portion of the unit for reception of a rudder post.

12. A metal tank unit for a boat having an exterior shape conforming to the shape of the stern bottom portion of a boat including upper convex and lower concave side portions exteriorly, a tube extending fore and aft through the bottom portion of such unit for reception of a propeller shaft, an upright tube extending through the aft portion of the unit for reception of a rudder post, a metal member of structural shape secured to the bottom of such unit and having its aft end projecting aft therebeyond, a rudder post journal element carried by the aft end of said structural member, and an upper rudder post supporting element secured to th rearward portion of such unit above said lower rudder post journal element and in alignment with said upright tube.

13. A boat hull comprising a hollow metal hull bottom portion extending from one end of the hull toward its center over only a portion of the length of the hull, a wooden hull top portion overlying the outer margin of said metal hull bottom portion, and means securing together said metal hull bottom portion and said wooden hull top portion in adjoining relationship to form a generally horizontal seam therebetween.

14. The boat hull defined in claim 13, in which the hollow metal hull bottom portion constitutes a liquid storage metal tank unit.

15. A boat hull comprising a hollow metal bow hull bottom portion having its outer marginal portion terminating slightly above the water line, a wooden hull top portion overlying the outer margin of said metal hull bottom portion, and means securing together said metal hull bottom portion and said wooden hull top portion in adjoining relationship to form a generally horizontal seam therebetween.

16. A boat hull comprising a hollow metal stern hull bottom portion, wooden curved stern bulwarks overlying the outer margin of said metal hull bottom portion, and means securing together the top of said metal hull portion and said wooden bulwarks in adjoining relationship to form a generally horizontal seam therebetween.

1'7. A boat hull comprising a hollow metal hull bottom portion, a wooden hull sturcture including a top portion, overlyin the outer margin of said metal hull bottom portion, and a bottom portion, and means securing together said metal hull bottom portion and said wooden hull structure in adjoining relationship to form an upright seam between the wooden and metal hull bottom portions and a generally horizontal seam between the wooden hull top portion and the metal hull bottom portion.

18. A boat hull comprising a hollow metal stern hull bottom portion, a hollow metal bow hull bottom portion, a wooden hull structure including a top portion, overlying the outer margin of a least one of said metal hull bottom portions, and a bottom portion disposed between said metal stern hull bottom portion and said metal bow hull bottom portion, and means securing said bottom wooden hull portion to said metal stern and bow hull bottom portions.

HOLLAND C. SABINS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 367,828 McIntyre Aug. 9, 1887 433,085 Keys July 29, 1890 703,413 Hayes July 1, 1902 1,011,464 Martin Dec. 12, 1911 1,293,063 Erickson Feb. 4, 1919

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