US2677139A

US2677139A - Chine plate construction

Info

Publication number: US2677139A
Application number: US114938A
Authority: US
Inventors: Donald Henry Canazzi
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-09-10
Filing date: 1949-09-10
Publication date: 1954-05-04
Anticipated expiration: 1971-05-04

Description

' May 4, 1954 H, D, CANAZZ. 2,677,139

CHINE PLATE CONSTRUCTION Filed Sept. 10, 1949 Jfenryfimald 602203;

Gttorneg Patented May 4, 1954 UNITED STATE PATENT OFFICE 2 Claims. 1

My invention relates to boat hulls and more particularly relates to power boat hulls formed to plane on the surface of a body of water when driven forward at an advanced speed.

In an eifort to produce boat hulls cheaply, especially power boat hulls, there has been a marked trend toward molding processes in which "the hulls are molded from several thin sheets of laminae of wood. In these molding processes the several sheets or laminae are placed on a hull form with the grain of adjacent laminae crossed and with a suitable water-proof bonding material interposed between the adjacent surfaces of the several sheets or laminae, so that when the laminae are molded to the shape of the hull form and are bonded together by pressure or by heat and pressure an inexpensive hull with the desired strength and rigidity is provided.

Crossing of the grain of the alternate laminae provides a strong, lightweight and rigid hull, however, because of such crossing of the grain of alternate laminae small radius bends in the hull are impractical and for this reason molded boat bulls are usually of the type known as round bottom boats in which a substantially flat bottom area merges or blends into the spaced angular-1y related sides of the hull through outwardly and upwardly extending and generously curved bilge portions. Round bottom boats," due to their curved bilge portion have considerably less flat bottom area than substantially flat or V bottom boats also known and herein referred to as square chine boats, and accordingly are less stable, i. round bottom boats tend to roll and tip'easily.

By reason of their smaller flat bottom areas round bottom boats displace more water than square chine boats and because of their greater displacement together with the tendency of the displaced water to adhere to the submerged surfaces of the hull, particularly the curved bilge portions, round bottom boats have a greater drag or friction, i. e. resistance to movement in water and require more power to attain and maintain a desired forward speed than square chine boats. The power required to move a round bottom boat through the water with sufficient forward speed to cause it to plane is also considerably greater than the power required to cause a comparable square chine boat to plane for the reason that the water displaced by a planing square chine boat leaves its chine cleanly, whereas the water displaced by a planing round bottom boat tends to hug.

and climb up its curved bilge portions and creates a drag or friction. Another undesirable characteristic of a conventional round bottom boat is that when it planes the water displaced forms a spray which, since the displaced water is not directed away from the hull, enters and wets the boat.

Notwithstanding the above stated disadvantages of round bottom boats, the trend is toward molded round bottom boats which admittedly have good sea keeping qualities, are stronger and lighter than other types of boats of comparable size and can be manufactured considerably cheaper.

An object of my invention is to provide a strong, light and low cost round bottom boat with additional stabilizing and planing surfaces in a simple and inexpensive manner whereby such a boat closely approximates the performance and desirable qualities of a comparable, but more expensive, square chine boat.

More specifically the objects of my invention are: to provide high quality and performance boats at a low cost by utilizing the cheaper manufacturing processes for molding round bottom boats of laminated, formed and bonded sheets of wood, i. e., plywood; to overcome the objectionable characteristics and to improve the recognized good qualities of molded round bottom boats; to provide a round bottom boat hull with a pair of chine plates which may be permanently secured to the curved bilge portions of the hull contiguous to its flat bottom area during or after its fabrication; to provide a pair of chine plates shaped, located, and secured to the curved bilge portions of a round bottom hull so as to form laterally disposed extensions of the bottom surfaces of the substantially flat bottom area of the hull for the greater portion of its length, whereby the lateral stability of the hull is improved; to provide a round bottom power boat hull with a pair of chine plates having their leading edges faired into the bull to move over the water smoothly and having their bottom surfaces generally formed as lateral extensions of the fiat f chines, thus reducing the drag or friction of the displaced water on the submerged portions of the hull and thus imparting an upward force or lift to the hull, whereby its planability and speed closely approximates that of a square chine boat, of comparable size and power, and; to provide a round bottom power boat hull with chine plates formed, located and secured to the hull so as not to appreciably affect the displacement or trim of the boat and to direct displaced water away from the hull so that spray does not enter and wet the boat.

In the drawing:

Figure 1 is a bottom plan view showing a molded round bottom power boat hull provided with chine plates constructed and secured to the boat bottom in accordance with my invention.

Figure 2 is a transverse sectional view taken on line 2-2 of Figure 1 and shown right side Figure 3 is a transverse sectional view similar to Figure 2 but taken on line 3-3 of Figure 1.

Figure 4 is an enlarged fragmentary sectional view of the formation of one of the chines as viewed in the plane of Figure 2.

Figure 5 is an enlarged fragmentary sectional View of the formation of one of the chines as viewed in the plane of Figure 3; and

Figure 6 is a perspective view of one of the chines.

Referring now to the drawings a round bottom type of power boat hull molded of laminated plywood and provided with wooden chine plates formed, located and secured to the hull, whereby the performance and other characteristics of the hull closely approximate that of a comparable square chine power boat hull, has been shown as a specific embodiment which exemplifies the principles of my invention.

The hull shown in the drawing and generally designated by the numeral i is a typical example i The curved side traces of the fiat bottom area H smoothly merge into outwardly curved bilge portions 14 which in turn smoothly merge into the angularly related sides E of the hull.

The curvature of the bilge portions 54 and the angular relation of the sides [5 vary throughout the length of the hull and, as viewed in the plane of Figure 2, the extent and curvature of the bilge portions M- is less than the extent and curvature of such portions in the plane of Figure 3, and

whereas, the sides iii diverge outwardly from the bilge portions in the plane of Figure 2 they converge inwardly from the bilge portions in the plane of Figure 3, all according to the accepted practice in forming molded round bottom boat hulls.

It is also usual practice in such boats to form the bottom of the hull with a centrally located reinforcing keel piece E6 to the center of which a keel i1 is secured and to provide the sides of the hull with suitably formed and located spray rails H! as indicated in the drawing.

In order to improve the stability, planability, speed-to-power and spray factors of round bottom power boat hulls to a degree approximately that of comparable square chine boat hulls I prefer to provide such hulls with a pair of wooden plates or chines each of which is formed so that its upper face 2| fits one of the curved bilge portions M when its curved inner edge 22 is contiguous to the curved side trace of the V-shaped flat bottom area II. By reason of the varying curvature of the bilge portions M to which the chines are fitted and secured, the cross sectional area of the substantially wedge shaped chines also varies throughout their length, being greater at the stern end and diminishing toward the forward end, and while the lower face 23 of each chine may form a coplanar outward extension of the fiat bottom area H I have found that chines having their lower faces directed outwardly and downwardly and slightly concave, at least for the major portion of their length, act to deflect the outwardly moving water downwardly thereby giving an added lift to the hull, and also cause the displaced water to leave the substantially square outer edge 24 of the chines more cleanly whereby the performance of the boat is improved generally.

The leading edge portions 25 of the chines 20 are rounded and faired as indicated at 26 and the inner edges 22 of the wedge-shaped chines are made as thin as possible, consistent with the strength necessary, so that when the chines are properly located and secured to the hull their surfaces 23 merge with the fiat bottom area II as smoothly as possible and thus the flow of water under the leading edges 25, under the flat bottom of the hull, and across the edges 22 and the surfaces 23 of the chines is smooth and the drag or friction of a hull provided with such chines is low.

The wooden chines 20 may be rigidly secured to the hull H) by having their inner faces 2| securely cemented to the bilge portions 14 and by the wood screws 21 in the manner shown or by other suitable means.

It has been found that when a round bottom" power boat hull is provided with chines of a length in about the order of sixty per cent (60%) of its length and that when the surfaces 23 of the chines are of a width to have a total combined fiat and concave face area of about twenty percent (20%) of the total flat bottom area of the hull, the overall efficiency and performance of such a boat is improved about 20 and closely approximates that of a square chine boat of comparable size and power.

The wooden chine plates and the molded plywood round bottom power boat hull shown and described are intended to be exemplary of the principles of my invention and it should be understood that both the boat hull and the chines which improve its performance, may be formed of other materials by various manufacturing processes so long as the chines are formed, located and secured to the hull in accordance with the appended claims.

I claim:

1. In a boat hull having an external substantially fiat generally horizontal bottom area with curved side traces and upwardly curved bilge portions and side wall areas, said horizontal bottom area extending for the greater portion of the length and breadth of the hull and gradually merging along each of its curved side traces into the external surface of one of the outwardly and upwardly curved bilge portions of the hull which surface in turn gradually merges into an external surface of the adjacent side of the hull, a pair of elongated wedge-shaped plates, each plate having a top surface shaped to fit the varying transverse and longitudinal curvature of a portion of the outer surface of one of the bilge portions-adjacent the side traces of said bottom area and each having a substantially flat bottom surface arranged substantially in the plane of and forming a lateral extension of the surface of the fiat horizontal bottom area, each deflecting plate having an outer face substantially at right angles to its bottom face, said outer face extending upwardly to the overlying bilge portion and forming an abrupt shoulder serving to space the lateral flow of water from the bilge portion and its superimposed external side surface of the hull, and means for rigidly securing each plate to its bilge portion, thereby affording increased transverse stability of the hull and said shoulder directing water displaced by forward movement of the hull away from the bilge portions.

2. An article of manufacture for improving the planability, transverse stability and spray deflecting characteristics of power boat hulls of the character described comprising a pair of elongated Wedge-shaped chine plates each having a top surface adapted to overlie and fit upon one of the longitudinally and transversely curved external chine areas located at opposite sides of a substantially fiat bottom area of the hull, each of said plates being of a length and longitudinally curved whereby it is adapted to follow one of the curved side traces of said flat bottom area from its rear end forwardly for a distance approximating between to of its length, each of said plates having a substantially flat bottom surface extending between its ends, its thin inner edge and its thick outer edge, and each being adapted to form a 10% to 15% substantially coplanar lateral extension of said fiat bottom area when secured to said chine area, and the surface of the thick outer edge of each plate extending substantially upright between its top and flat bottom surfaces, thereby providing an abrupt outer shoulder which serves to deflect water moving outwardly across its flat bottom surface away from its outer edge.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 649,525 Nichol May 15, 1900 1,674,665 Ruthenburg June 26, 1928 1,885,198 Hale Nov. 1, 1932 2,165,545 Grant July 11, 1939 2,234,899 Higgins Mar. 11, 1941 2,342,023 Vidal et al. Feb. 15, 1944