US20090318039A1

US20090318039A1 - Boat engine cooling system

Info

Publication number: US20090318039A1
Application number: US12/379,179
Authority: US
Inventors: Kevin P. Hays
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-06-23
Filing date: 2009-02-13
Publication date: 2009-12-24

Abstract

The boat engine cooling system provides cooling of the engine of a boat or other nautical vehicle through both chemical coolant, such as an antifreeze solution, and environmental water; i.e., the water the vehicle is passing through. In use, heated engine coolant is expelled by the engine and passes through a coolant inlet port formed through a hollow tank, where it is transported through a coolant pipe to the engine. Further, water from the environment (i.e., the lake, ocean or other body of water the vehicle is passing through) is injected into a cooling reservoir in the hollow tank through a water inlet port. The engine coolant passing through a central portion of the coolant pipe is cooled by the water in the cooling reservoir prior to circulating back through the engine.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/129,390, filed Jun. 23, 2008.

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to inboard motors for boats, and particularly to a boat engine cooling system for an inboard motor.
2. Description of the Related Art
Typical inboard boat motors operate at temperatures of approximately 180° F. It is well known in the art to use the environmental water (i.e., the water of the lake, ocean or other body of water the boat is traveling in) to cool the engine, with this water being passed into or around the engine in a conventional manner.
However, such systems rely on pure water for the cooling of the engine. Due to contaminants, such as chemical pollutants, as well as natural marine life, filter systems must be used before the water is passed to the engine. Such filters must be changed regularly, can easily become clogged, and are not 100% effective, thus resulting in clogged engines, broken blocks and the like, which must be fixed or replaced. Further, environmental laws of some jurisdictions have required this type of system to be banned, since the water passing through the engine and back into the environment may be contaminated by the engine. It would be desirable to cool the engine of the boat with environmental water, but without the risk of contaminating either the environment or the engine. Thus, a boat engine cooling system solving the aforementioned problems is desired.

SUMMARY OF THE INVENTION

The boat engine cooling system provides cooling of the engine of a boat or other nautical craft through injection of both chemical engine coolant, such as antifreeze, and environmental water i.e., the water the vehicle is passing through. The boat engine cooling system includes a hollow tank adapted for mounting within the boat or other vehicle. The hollow tank defines an open interior region therein. An engine coolant inlet port, an engine coolant outlet port, a water inlet port and at least one water outlet port are all formed through an outer wall of the hollow tank.
A partition wall is mounted within the hollow tank. The partition wall divides the open interior region of the hollow tank into a cooling region and an inner tank. The partition wall has a passage formed therethrough.
Both the hollow tank and a boat engine are mounted to the boat (or other nautical craft) in a conventional manner, with the engine being in fluid communication with the hollow tank. A coolant pipe having opposed first and second ends extends into the hollow tank. The first end of the coolant pipe is joined to the coolant inlet port, and a central portion of the coolant pipe extends within the cooling region of the hollow tank. The coolant pipe passes through the passage formed through the partitioning wall, and the second end thereof terminates in a spout, for injecting cooled engine coolant into the inner tank.
In use, heated engine coolant passes through the coolant inlet port and is transported through the coolant pipe to the inner tank, and then out of the inner tank and back to the engine for circulation through coolant passages defined in the engine. Further, water from the environment (i.e., the lake, ocean or other body of water the vehicle is passing through) is injected into the cooling region of the hollow tank through the water inlet port. The engine coolant passing through the central portion of the coolant pipe is cooled by heat transfer with the water in the cooling region of the hollow tank prior to transport thereof to the engine.
These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The sole FIGURE is a diagrammatic side view of the boat engine cooling system according to the present invention.

Similar reference characters denote corresponding features consistently throughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The boat engine cooling system 10 provides cooling of the engine 16 of a boat or other nautical craft through injection of both chemical engine coolant, such as antifreeze, and environmental water; i.e., the water the boat is passing through. The boat engine cooling system is preferably applied to an inboard engine 16. It should be understood that the system 10 and engine 16 shown in the sole drawing FIGURE may be used with any type of marine propulsion system, whether an inboard or outboard engine.
The boat engine cooling system 10 includes a hollow tank 14. As shown in the drawing, the hollow tank 14 defines a reservoir. Hollow tank 14 is mounted within or on the boat and is connected to the boat engine 16, as will be described below in greater detail. An engine coolant inlet port 24, an engine coolant outlet port 30, a water inlet port 36 and a pair of water outlet ports 41, 42 are all formed through an outer wall 15 of the hollow tank 14. A pressure relief port 32 may also be formed through outer wall 15 adjacent inner tank 19, and may be releasably covered by a cap or other seal 34. Hollow tank 14 may have any desired shape and dimensions. Exemplary dimensions for the cylindrical tank shown in the drawing are a length of approximately nineteen inches and a diameter of between approximately ten and twelve inches.
A bulkhead or partition 20 divides the open interior region of the hollow tank 14 into a cooling reservoir 17 and an inner tank 19. Partition wall 20 is shown for exemplary purposes only. It should be understood that the size, shape, and location of partition wall 20 depend upon the size and contouring of outer tank 14. Partition wall 20 has a passage 28 formed therethrough, as will be described in greater detail below. Further, as will be described in greater detail below, partition wall 20 maintains a fluid-tight compartment 19 for receiving engine coolant 23.
As shown, a coolant pipe 26 extends through the hollow tank 14. In the FIGURE, the coolant pipe 26 is shown as a substantially serpentine coil, although coolant pipe 26 may have any shape that maximizes the surface area of pipe 26 exposed within the hollow tank 14 for heat exchange. Coolant pipe 26 is formed from a thermally conductive material, such as aluminum.
The coolant pipe 26 is joined to coolant inlet port 24 and extends within the cooling reservoir 17 of the hollow tank 14, as shown. The coolant pipe 26 passes through the passage 28 formed through partition wall 20 and terminates in a spout 50.
In use, heated engine coolant 22, which has been heated by boat engine 16, passes through the coolant inlet port 24 and is transported through the coolant pipe 26 to the inner tank 19. Heated engine coolant 22 has been heated during work within the boat engine 16 and is expelled under pressure by engine 16 through pipe 26. As will be described in further detail below, the heated coolant 22 is cooled within region 17 of tank 14, resulting in cooled engine coolant 23. Cooled engine coolant 23 is expelled from pipe 26 through spout 50 to be collected within inner tank 19. The cooled engine coolant 23 is drawn from inner tank 19 through port 30 by engine 16 for usage therein. The engine coolant passes through a closed system, thus preventing contamination of the coolant through the cooling process. A coolant expansion tank 52 may further be mounted within the boat and is in fluid communication with inner tank 19 through port 32. In the event of an excess volume of collected coolant, or excessive fluid pressure within inner tank 19, the excess coolant can be vented through a pressure relief valve fitted in port 32 into the coolant expansion tank 52.
Water 40 from the environment (i.e., the lake, ocean or other body of water the boat is passing through) is injected into the cooling reservoir 17 of the hollow tank 14 through the water inlet port 36. Water 40 is injected into cooling region 17 through line 38 and water inlet port 36 by any suitable pressurized pump. The water 40 remains within cooling reservoir 17 and is not mixed with the engine coolant 22, 23, thus allowing the engine 16 to remain free of contamination from the external water supply and preventing contamination from engine 16 into the water supply.
The engine coolant 22 passing through coolant pipe 26 is cooled by heat exchange with water 40 in cooling reservoir 17 prior to transport thereof to the engine 16. Water 40 exits cooling region 17 through water outlet ports 41, 42 and lines 43, 44, respectively, and fresh, relatively cool water is drawn through line 38 and inlet port 36 to replace it. Water is drawn through ports 41, 42 through the usage of any suitable type of pump or the like. Typical boat motors equipped with cooling system 10 operate at temperatures of approximately 180° F. The heated coolant 22 is expelled at approximately this temperature and is then cooled by the environmental water 40 drawn into tank 14. The environmental water is typically at a temperature of approximately 70° F.
It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims.

Claims

1. A boat engine cooling system, comprising:

a hollow tank having an outer wall and an engine coolant inlet port, an engine coolant outlet port, a water inlet port and at least one water outlet port formed through the outer wall;

an inner wall mounted within said hollow tank, the inner wall dividing the hollow tank into a cooling reservoir and an inner tank, the inner wall having a passage formed therethrough, the cooling reservoir being in communication with the engine coolant inlet port, the water inlet port and the at least one water outlet port, the inner tank being in communication with the engine coolant outlet port;

a coolant pipe having an inlet extending into the tank through the engine coolant inlet port and an outlet extending through the passage formed through the inner wall into the inner tank, the inlet of the coolant pipe and the engine coolant outlet port being adapted for attachment to a boat engine in order to circulate a chemical coolant through the engine, the coolant pipe being formed from a thermally conductive material and forming a heat exchange coil within the tank;

means for pumping a chemical coolant through the coolant pipe; and

means for drawing cool water through the cooling reservoir;

whereby the chemical coolant cools the engine and is itself cooled by heat exchange with cool water in the cooling reservoir.

2. The boat engine cooling system as recited in claim 1, further comprising a pressure relief port formed through said hollow tank, the pressure relief port being in communication with the inner tank.

3. The boat engine cooling system as recited in claim 2, further comprising a coolant expansion tank positioned external to said hollow tank, the coolant expansion tank being in fluid communication with the pressure relief port.

4. The boat engine cooling system as recited in claim 1, wherein said coolant pipe has a substantially serpentine contour.

5. The boat engine cooling system as recited in claim 1, wherein the passage formed through said inner wall is positioned above the engine coolant outlet port.

6. The boat engine cooling system as recited in claim 1, further comprising means for expelling water from the cooling reservoir through the at least one water outlet port.

7. The boat engine cooling system as recited in claim 1, wherein the water inlet port is formed through an upper portion of said hollow tank.

8. The boat engine cooling system as recited in claim 7, wherein the at least one water outlet port is formed through a lower portion of said hollow tank.

9. The boat engine cooling system as recited in claim 8, further comprising a pressure relief port formed through the upper portion of said hollow tank, the pressure relief port being in communication with the inner tank.

10. The boat engine cooling system as recited in claim 9, further comprising a coolant expansion tank positioned external to said hollow tank, the coolant expansion tank being in fluid communication with the pressure relief port.

11. A boat engine cooling system, comprising:

an inner wall mounted within the hollow tank, the inner wall dividing the hollow tank into a cooling reservoir and an inner tank, the inner wall having a passage formed therethrough, the cooling reservoir being in communication with the engine coolant inlet port, the water inlet port and the at least one water outlet port, the inner tank being in communication with the engine coolant outlet port;

means for pumping a chemical coolant through the coolant pipe;

means for drawing cool water through the cooling reservoir; and

means for expelling water from the cooling reservoir through the at least one water outlet port;

12. The boat engine cooling system as recited in claim 11, further comprising a pressure relief port formed through said hollow tank, the pressure relief port being in communication with the inner tank.

13. The boat engine cooling system as recited in claim 12, further comprising a coolant expansion tank positioned external to said hollow tank, the coolant expansion tank being in fluid communication with the pressure relief port.

14. The boat engine cooling system as recited in claim 11, wherein said coolant pipe has a substantially serpentine contour.

15. The boat engine cooling system as recited in claim 11, wherein the passage formed through said inner wall is positioned above the engine coolant outlet port.

16. The boat engine cooling system as recited in claim 11, wherein the water inlet port is formed through an upper portion of said hollow tank.

17. The boat engine cooling system as recited in claim 16, wherein the at least one water outlet port is formed through a lower portion of said hollow tank.

18. The boat engine cooling system as recited in claim 17, further comprising a pressure relief port formed through the upper portion of said hollow tank, the pressure relief port being in communication with the inner tank.

19. The boat engine cooling system as recited in claim 18, further comprising a coolant expansion tank positioned external to said hollow tank, the coolant expansion tank being in fluid communication with the pressure relief port.

20. A boat engine cooling system, comprising:

a hollow tank having an outer wall and an engine coolant inlet port, an engine coolant outlet port, a water inlet port and at least one water outlet port formed through the outer wall, the tank forming a cooling reservoir;

a coolant pipe having an inlet extending into the tank and an outlet extending from the tank, the inlet and the outlet being adapted for attachment to a boat engine in order to circulate a chemical coolant through the engine, the coolant pipe being formed from a thermally conductive material and forming a heat exchange coil within the tank;

means for pumping a chemical coolant through the coolant pipe; and

means for drawing cool water through the cooling reservoir;

wherein the chemical coolant cools the engine and is itself cooled by heat exchange with cool water in the cooling reservoir.