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Publication numberUS3702485 A
Publication typeGrant
Publication dateNov 14, 1972
Filing dateDec 7, 1970
Priority dateDec 7, 1970
Publication numberUS 3702485 A, US 3702485A, US-A-3702485, US3702485 A, US3702485A
InventorsThompson Theodore G
Original AssigneeChris Craft Ind Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Outboard motorboat with inboard mount
US 3702485 A
An outboard motorboat has an inboard mounting well. A gate in the transom of the boat vents engine fumes and precludes entry of sea water when the boat motion is reversed. The well functions as a channel in the bottom of the hull for directing a stream of water through the propeller and for reducing the hull surface area in contact with the water.
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Description  (OCR text may contain errors)

United States Patent Thompson [54] OUTBOARD MOTORBOAT WITH INBOARD MOUNT [72] Inventor: Theodore G. Thompson, Homer,

[73] Assignee: Chris-Craft Industries, Inc., Pompano Beach, Fla.

22 Filed: Dec. 7, 1970 21 App1.No.: 95,529

[52] US. Cl. ..9/6, 115/41 R [51] Int. Cl. ..B63b 3/04 [58] FieldofSearch ..9/6, 1 R; 115/17, 18,41;

l14/66.5 R, 66.5 P

[56] References Cited UNITED STATES PATENTS I Watkinsm, ..1 15/41 R Nov. 14, 1972 2,764,119 9/1956 Sigler ..9/6 X 3,063,068 1 H1962 Calkinsu ..9/6 3,371,362 3/ 1968 Butler ..9/6

Primary Examiner-Mi1ton Buchler Assistant ExaminerCa.r1 A. Rutledge Attorney-Louis Bernat [57] ABSTRACT An outboard motorboat has an inboard mounting well. A gate in the transom of the boat vents engine fumes I and precludes entry of sea water when the boat mo tion is reversed. The well functions as a-channel in the bottom of the hull for directing a stream of water through the propeller and for reducing the hull surface area in contact with the water.

4 Clairm, 7 Drawing Figures PATENTEDmv 14 m2 3.702.485

sum 1 or 2 lNl/E/V TOR. THEODORE G. THOMPSON OUTBOARD MOTORBOAT WITH INBOARD MOUNT This invention relates to outboard motorboats and more particularly to outboard motorboats which are arranged to have the appearance of an inboard motorboat with an improved tunnel drive channel in the bottom of the hull.

Outboard motorboats are very popular and well known vehicles, well adapted for popular usage. They are light, low-cost, easy to handle and transport. Modern, high power outboard motors are able to drive these boats through the water at very high speed. In most respects, an outboard motor is able to perform any task which the average owner could want.

On the other hand, inboard motorboats are in a different price class and are much more expensive than the outboard boats. However, there is not too much difference in performance between many of the smaller, modern day inboard and larger outboard motorboats. Thus, a principal reason for the continued sale of these smaller inboard boats is the snob appeal resulting from an appearance of a more expensive vehicle. If the outboard boats looked about the same as the inboard boats, many people would prefer to buy them.

Accordingly, an object of the invention is to provide new and improved outboard motorboats. In particular, an object is to provide outboard motorboats having the appearance of inboard motorboats. In this connection, an object is to provide boats with the low-cost appeal of outboard boats and the high-cost appearance of inboard boats. In particular, an object is to provide a'hull with a channel to direct a flow of water through the propeller on the outboard motor.

Another object is to provide low-cost boats which are rugged and can be hauled about on a trailer. Here an object is to provide the ease and convenience of an outboard boat with the sales appeal of an inboard boat.

In keeping with an aspect of the invention, these and other objects are accomplished by an outboard boat having a well therein for receiving an outboard motor. The well forms a channel in the bottom of the hull for directing water through the propeller on the outboard motor and for reducing the area of the hull in contact with the water. When the well is normally covered by a suitable hatch cover, the motor cannot be seen at the back of the boat. A gate or door is cut into the transom and hinged to hang down and close an exit tunnel from the well which receives the outboard motor. When the boat is under way, water resistance pushes against the transom gate and causes it to open slightly to eliminate fumes in the well. The water resistance also causes the transom gate to close when the boat is reversed, thus preventing the sea water from backing into the well.

' The nature of a preferred embodiment for accom plishing these and other objects will become more apparent from a study of the attached drawings, in which:

FIG. 1 is a perspective view of the back of the inventive boat with the hatch cover shown in phantom over an outboard motor mounted well;

FIG. 2 is a side elevation view of the outboard motor mounted in a cross section of the well, with the boat shown in phantom;

FIG. 3 is a top plan view of the outboard motor mounted in the well, with the hatch cover removed and the boat again shown in phantom;

FIG. 4 is an exploded view showing the rear end of the hull with the outboard motor well, the motor, and the hatch cover; and

FIGS. 5, 6, and 7 are schematic side views with the transom gate open when the boat is in forward motion, closed when the boat is in reverse motion, and swung up while the boat is being hauled on a trailer.

Throughout the various figures the same reference characters identify with same parts. More particularly, a motor boat hull 10 has the lines generally considered to be those of an inboard motorboat. There are conventional seats 11, 12, and a steering wheel 13. The steering wheel may be connected to an outboard motor 14 by any suitable cables. Therefore, as the wheel 13 is turned, the outboard motor 14 turns to steer the boat.

In keeping with an aspect of the invention, a boxJike well 15 is formed in the boat near the stern. Preferably, the front panel of the well 15 is reinforced, as at 16 (FIG. 4) to form a strong support for the motor. The outboard motor 14 clamps on the member 16 in a normal manner.

The bottom of the well forms a channel 17 at the bottom and stem end of the hull. This way, the well forms a channel 17 for directing a stream of water through the propeller 18 on the outboard motor. It also reduces the area of the hull in contact with the water.

The top of the well 15 is covered by a hatch cover 19 which completely conceals the outboard motor 14 from view. To reveal the arrangement of the outboard motor and the mounting arrangement, FIG. 1 shows the boat with the hatch cover 19 in phantom lines.

This arrangement presents two problems. FIrst, fumes and exhaust tend to accumulate in the well.

Second, the sea water tends to back up into the well when the boat is reversed. To overcome preclude these and other problems, the invention provides a transom gate 20 hinged at the top and hanging down under gravity to close the back of the well 15 while the boat is standing motionless or reversing, and opens when the boat is in forward motion.

More particularly, the transom gate 20 is hinged to the hull at 21. Preferably, the transom is set slightly off plumb, as indicated by the angle A in FIG. 4. Therefore, gravity causes the transom gate 20 to rest, in a closed position, against the transom, when the boat is stopped. As best seen in FIG. 6, the bottom edge 22 of the transom gate 20 is a distance B in the range of about three-quarters of an inch to about two and one half inches, with a preferred distance B of about one and one-half inches above the waterline 23 at all times, even when the boat may be fully loaded. This dimension provides adequate ventilation space for motor fumes to escape from the well.

As shown in FIG. 4, the motor 14 is installed in the boat by first removing the hatch cover 19. Then, the motor 14 is placed in the well 15. The usual motor clamp 25 is fitted over the reinforced panel 16 and fastened in position. The motor is in proper position when the anticavitation plate 27 is in approximately a horizontal line which is an extension of the bottom of the hull. The propeller 18 is suspended below the hull line when the motor is in operating position.

As best seen in FIG. 5, the forward motion of the boat causes water to be discharged behind the boat. As the boat moves forward through the water, the sea 30 tends to push the transom gate 20 outwardly. This allows free passage of water and motor fumes out of the tunnel formed by the well 15.-

When the boat is reversed, the water tends to pile up and push against the transom gate 20, as indicated by the arrows 31. Thus, the boat may be driven backward through the water without any pile up of sea water inside the well 15.

Likewise, if the boat is standing in water, any waves lapping against the transom will tend to push the transom gate 20 toward its shut position. When the boat isstanding still with the motor idling, the sea gate 20 may be pulled up to an open position by any suitable means, such as a lever or cable. This enables engine fumes inside the well to escape.

When the boat is loaded onto a trailer 32 (Fig. 7) the motor 14 may be tipped up in a conventional manner. The hatch cover 19 may be removed to allow the motor to tip upward. However, this is not necessary if adequate space is provided under the hatch cover. The transom gate 20 is raised by the outboard motor propeller and guard assembly. Alternatively, the same latching mechanism may be used to hold the gate 20 in an open position while the motor is idling and while the motor is tipped in the hauling position.

A further requirement may be to place a sound insulating material in the walls of the well 15 to help reduce motor noise. Still other refinements will readily occur to those who are skilled in the art. Therefore, the appended claims are to be construed to cover all equivalent structures.

We claim:

1. An outboard motorboat comprising a well formed in the bottom of the hull near the stem of the boat, means for mounting an outboard motor in said well, the back wall of said well being at the transom of said boat, control means in said transom for enabling sea water to leave said well when said boat is under way in a forward direction and for preventing sea water from entering said well when said boat is under way in a reversed direction wherein said control means comprises a gate, hinged at its top to an opening in said transom, said gate hanging down and closing said well to preclude an entry of sea water into said well while said boat is reversed, and opening responsive to water resistance when said boat is in forward motion.

, 2. The boat of claim 1 wherein the bottom of said gate terminates slightly above the waterline when said boat is in the water.

3. The boat of claim 1 wherein said control means further comprises a tunnel cut into said transom, said gate being hinged at its top to the bottom edge of the tunnel in said transom and hanging down under gravity toward the waterline, said hinge being high enough to permit the propeller of said motor to tip upwardly when said boat is being hauled, and said gate hanging downwardly to about one inch above the waterline.

4. The boat of claim 3 wherein said well forms a channel for directing water toward said propeller.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2764119 *Oct 28, 1955Sep 25, 1956Sigler Ernest JCombined outboard motor mount and fuel tank
US3063068 *Dec 24, 1958Nov 13, 1962Calkins Craft Boat CoBoat construction
US3371362 *Jan 24, 1966Mar 5, 1968Frank W. ButlerAdjustable outboard well
US3452704 *Jul 14, 1966Jul 1, 1969Outboard Marine CorpEngine mounted on a gimbal-like frame
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3901177 *Aug 20, 1973Aug 26, 1975Scott Claude WorthingtonMarine propulsion apparatus
US4907994 *Jun 15, 1987Mar 13, 1990Us Marine CorporationL-drive
US4972809 *Apr 13, 1989Nov 27, 1990Sanshin Kogyo Kabushiki KaishaPower unit of inboard/outboard
US5176551 *Mar 6, 1992Jan 5, 1993Outboard Marine CorporationArrangement for supplying combustion air to an outboard motor
US5188548 *Nov 22, 1991Feb 23, 1993Outboard Marine CorporationMarine propulsion device mounting arrangement
US5307755 *May 13, 1992May 3, 1994Lumpkin Anthony PWork vessel and trailer
US5409409 *Nov 22, 1991Apr 25, 1995Outboard Marine CorporationMarine apparatus
US5536187 *Sep 22, 1994Jul 16, 1996Sanshin Kogyo Kabushiki KaishaOutboard jet drive for watercraft
US5542370 *Sep 22, 1994Aug 6, 1996Castleberry; Morris D.Portable fishing deck and boat with fishing deck
US5562511 *Jan 23, 1995Oct 8, 1996Outboard Marine CorporationMarine apparatus
US6045420 *Jan 19, 1999Apr 4, 2000Small; Mark S.Semi-enclosed surfacing propeller driver system including air induction
US20120325136 *Feb 1, 2012Dec 27, 2012Mcgill Jr William HHull design with engine air flow system
DE3824378A1 *Jul 19, 1988Jan 25, 1990Andreas Dr TruppCapsize-proof motor boat, mainly for sports purposes
WO2000043266A1Jan 18, 2000Jul 27, 2000Mark S SmallSemi-enclosed surfacing propeller arrangement including air induction
WO2006102779A1 *Mar 24, 2006Oct 5, 2006Peter A MuellerFixing body for watercraft
U.S. Classification114/355, D12/300, 440/69
International ClassificationB63B3/70, B63H20/04, B63H20/00, B63H21/00, B63B3/00, B63H21/30
Cooperative ClassificationB63H21/30, B63H20/04, B63B3/70
European ClassificationB63H20/04, B63H21/30, B63B3/70