US1750743A - Speed boat - Google Patents

Description

- 4. 'IH'IHIIIHTJZ l l March 18, 1930.

Patented Mar. 18, 1930 UNITED STATES PATENT oFFicl-z SPEED BOAT Application led October 22, 1929. Serial No. 401,536.

My invention is concerned with racing boats of the type adapted to be driven by an outboard motor. Such boats are relatively small and light in weight. On the bottom,

the hull is usually provided with one or more steps which enable the boat to plane over the surface of the water. Near the rear end of the boat there is an open cockpit, and the bow of the boat is decked over to provide a cowl which serves to protect the occupant of the cockpit from the relative air currents.

The speed which such boats a'ttain-namely forty miles per hour and upwards-is so great that the resistance offered to forward '15 movement by the air is a factor which must be considered if maximum speed is to be derived. Not only does the action of the air on those parts of the boat above the waterline affect the speed of the boat, but it also affects its stability. In attempting to decrease the air resistance, prior designers of boats have almost uniformly constructed the cowl at the bow of the boat along the conventional stream-lines. That is, the cowl has been Y shaped so that substantially all portions of it were outwardly convex. Such a cowl is better than no cowl at all, but I have found that it is possible by departing materially from the conventional stream-line cowlshape, to increase both the speed and the stability of the boat.

My improved cowl, instead of being outwardly convex at substantially all points, is outwardly concave at the front and sides, and is convex only at and near the middle and rear end, this convex portion being raised to serve as a protection for the occupant of the boat.

The accompanying drawing illustrates my invention: Figs. l, 2, and 3 are respectively a side elevation, a plan, and a front end elevation of a boat embodying my improved cowl-shape; and Fig. 4 is a transverse section on the line 4 4 of Fig. 2.

My invention is not directly concerned with the shape of the boat hull nor with the arrangement of the cockpit. As shown in the drawing, the hull 10 is provided with vertical sides 11 and with a bottom 12 which, at

0 an intermediate point, is formed with a transverse step 13. Ahead of this step, there is a downwardly extending iin or keel 14 designed to prevent lateral movement of the boat. The sides 11 and bottom 12 are supported from transverse ribs 15 in the conventional manner.

At the rear end, the boat is provided with an open cockpit 16. The motor (not shown) which drives the boat is mounted at the stern in the usual manner.

As stated above, my invention is concerned with the shape of the cowl 17 which extends rearwardly from the bow of the boat to approximately the front end of the cockpit. At its rear end, this cowl 17 is of a hight suiiicient to protect the occupant from the relative air current. This is substantially the highest point of the cowl. From this highest point, the cowl slopes downwardly both laterally and forwardly to the top edges of the boat-sides 11 and to the bow. This slope is not a straight-line slope, the cowl being convex outwardly at and near its highest point and concave outwardly near the top edges of the boat-sides 11 and near the bow as is clear from Figs. 1, 3, and 4. The upper surface of the cowl near its side edges lies below a line extending between the highest point of the cowl and the top of the adjacent boatside. This is also true, although to a less extent, at and near the bowof the boat.

The cowl 17 is desirably formed of plywood or of layers of veneer supported at its outer edges by the sidesll of the boat, at its rear by a transverse cross member 19, and at its center by a longitudinally extending brace 20. By forming the cowl of veneer or ply wood, the necessity for transverse ribs or other intermediate supports is eliminated.

It will be apparent from Fig. 3 that the maximum cross-sectional area of the entire boat is materially less than it would be if provided with a cowl which, at its rear en'd, has the same hight as my improved cowl but which is convex outwardly at substantially all points. I believe that this decrease in maximum crossesectional area decreases the resistance which the air offers to forward movement of the boat and thereby increases speed. In actual speed tests, I have found that a boat with my improved form of cowl is appreciably faster than a boat otherwise similar but provided with a cowl of the conventional stream-line shape. The box construction of the whole forward end of the boat decreases weight. In addition, the reduction in cross-sectional area of the cowl lowers the center of gravity. Not only does my cowl increase the speed of the boat, but it also increases its stability. I believe this is due in part to the decreased weight and lowered center of gravity and in part to the fact that the reaction of the air on my cowl tends to hold the boat against the water.

I claim as my invention:

l. In a boat having a cockpit, a cowl eX- tending rearwardly from the bow to a point adjacent the cockpit, said cowl having near its rear end a central raised portion from which the cowl slopes forwardly and laterally to the bow and sides, the cowl being outwardly conveXAat said raised portion and outwardly concave near the sides and bow.

2. In a boat having a cock it, a cowl eX- tending rearwardly from the bow to a point adjacent the cockpit, said cowl having near its rear end a central raised portion from which the cowl slopes forwardly and laterally to the bow and sides, the upper surface of said cowl for a material distance inward from the sides and rearward from the bow lying below straight lines extending from the highest point of the raised portion to the upper edge of the sides and bow.

3. In a boat having a cockpit, a cowl eX- tending rearwardly from the bow to a point adjacent the cockpit, said cowl having near its rear end a central raised portion from which the cowl slopes forwardly and laterally to the bow and sides, the upper surface of said cowl for a material distance inward from the sides lying below straight lines eX- tending from the highest point of the raised portion to the upper edge of the sides.

In witness whereof, I have hereunto set my hand at Indianapolis, Indiana, this 18th day of October, A. D. one thousand nine hundred and twenty-nine.

FRANK B. BREMERMAN.

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