The present invention relates to an integrated bell housing, particularly for a marine internal combustion engine, which houses a geared transmission for the engine and which carries certain engine accessories thereon.
Historically, certain engine accessories such as the alternator, supercharger, water pump, are typically located on the front of the internal combustion engine and are driven from the engine with belts and pulleys. Of course, the starter is rear mounted and drives the engine at start-up engaging with the flywheel. In a marine environment, it is beneficial to reduce the overall length of the engine while maintaining the high performance of the marine internal combustion engine. Further, in a marine environment which is subject to the corrosive effect of salt and degradation by water and humidity, belts and pulleys are high maintenance items.
In the past, starters are sometimes coupled to the engine by a gear ring attached on or about the flywheel wherein the flywheel is typically a connection point to the transmission for the internal combustion engine.
It is an object of the present invention to mount a supercharger (if necessary), alternator and a water pump on the exterior of a bell housing and transmission case and drive those engine accessories from the flywheel (the supercharger and alternator) and from a pump drive shaft keyed to the crankshaft of the engine (the water pump).
It is a further object of the present invention to provide an integrated bell housing wherein the supercharger, alternator, water pump and starter are mounted on the exterior of the bell housing and transmission case. The supercharger may be omitted as appropriate.
It is an additional object of the present invention to provide a marine engine with an integrated bell housing which is generally smaller in length than comparable marine engines due to the repositioning of engine accessories and utilization of the integrated bell housing.
The integrated bell housing, employed on a marine internal combustion engine, carries on its exterior engine accessories such as a supercharger, an alternator, a water pump and a starter. The engine has a crankshaft attaching flange extending into the interior space of the bell housing to which is coupled the flywheel. The bell housing also encloses a geared transmission which is coupled to the crankshaft via a flex plate. The integrated bell housing includes mounting system for the supercharger, alternator and starter. The water pump is driven from a shaft connecting to the crankshaft through the rear of the transmission case. The flywheel incorporates two gear faces for the purpose of driving engine accessories. A first complementary gear is coupled to a supercharger drive shaft rotatably mounted through the bell housing such that the flywheel drives the supercharger. A second complementary gear is coupled to an alternator drive shaft rotatably mounted through the bell housing such that the flywheel drives the alternator. A water pump drive shaft is keyed to the crankshaft and is rotatably mounted through the transmission housing such that the crankshaft of the engine drives the water pump. The starter is mounted on the bell housing and a starter drive shaft is rotatably mounted through the bell housing such that the starter can be adopted to drive the flywheel to start the engine.
Further objects and advantages of the present invention can be found in the detailed description of the preferred embodiments when taken in conjunction with the accompanying drawings in which:
The present invention relates to an integrated transmission bell housing for an internal combustion engine, and particularly for a marine internal combustion engine. In one working embodiment, the integrated bell housing is utilized in conjunction with a GENERAL MOTORS (GM) 60 degree V6 internal combustion engine. Utilizing the integrated bell housing with engine accessories such as a supercharger, alternator, water pump and starter mounted on the bell housing and transmission case, the specially configured marine internal combustion engine provides the following characteristics:
The specially configured marine engine has been designed for easy maintenance and reduces or eliminates belts, pulleys, hoses and hose clamps on the motor relative to the supercharger, alternator, water pump and starter. The supercharger may be omitted in certain constructions. The peripheral components are geared driven either from the flywheel or from the crankshaft and are mounted on the top side of the integrated bell housing and/or transmission case for easy access. Therefore, the user need not adjust belts and pulleys to drive those engine accessories. This reduces maintenance and eliminates premature component failures. Some advantages of the integrated bell housing combined with the marine internal combustion engine configured as a GM 60 degree V6 is a compact size which fits under the floor and in the space of a typical outboard engine well. This provides more usable deck space and cockpit space for fishing, diving, docking or other marine activities. The specially configured marine engine is only 32 inches long and 24 inches wide compared with a 47 inch long and 28 inch wide which is typical of 5.7LTR rated for 300 horsepower. As shown in
Accessory mount area 24 also includes a supercharger mount region 41 on bell housing 20.
The integrated transmission bell housing accommodates gear driven components of alternator, supercharger, direct drive, water pump and starter. Historically all of these components in the marine industry have been driven from the front of the engine with belts and pulleys. The present approach is to eliminate this high maintenance system by running them off the flywheel as gear driven components. Only starters have been known to be configured to be gear driven by a gear ring attached around the flywheel. The gear ring on a standard flywheel is too soft to be used to run any other continuous devices due to the high load characteristics. For this reason, the invention uses one of two methods to run the other components. (1) The preferred method is to use and manufacture a flywheel with the needed gears cut into the flywheel to run each of the needed components. (2) Alternatively, a standard flywheel may be used and additional custom gear rings attached to run the components.
Alternator: The alternator of choice is designed to run to a maximum RPM of 15,000 to 18,000 assuming the use of a 12 inch flywheel gear and 4 inch gear on the alternator. The ratio becomes 3 to 1. With a maximum engine RPM of 5200, the alternator will spin in the 15,600 RPM range. Depending on where the gear is placed, as an example, it could be 9 inches at the flywheel and 3 at the alternator, the same end result can be achieved. The alternator is placed high on the bell housing for easy access.
Supercharger: The supercharger is driven off a single shaft placed into the housing vertically and driven off a face gear on the flywheel. The same principals apply. Using a 12 inch flywheel gear and 1 inch gear on the flywheel, the system will produce a ratio of 12 to 1 at 5200 engine RPM and the supercharge impeller will spin at roughly 62,000 RPM to develop the air pressure needed to achieve horsepower goals. Another alternative to this gear ratio is to install an idler gear which would also change the rotation of the supercharger. As with the alternator, gear ratios may be achieved by varying the size of gears access. Additionally, a more efficient turbo style impeller is to used gain greater efficiencies. The uniqueness of this design is that it offers the most efficient engine performance in a very small package with very few parts making it far less susceptible to component failure seen in typical centrifugal superchargers.
Intercooler: In the 300 horsepower model or any engine using this conversion system, an intercooler is needed or preferred if the boost levels to generate the desired horsepower exceed roughly 9 pounds of boost pressure. This cooling of the air charge assures that the engine will not experience harmful detonation at a given fuel octane rating. While there are other methods to control this action such as reducing timing or raising octane, intercooling offers the greatest level of protection over a wide range of variables. To understand how this principal works, it is helpful to understand the basics of supercharger technology and why superchargers make more power. A rough starting estimate to calculate HP gain is to take boost (say 5 psi) and multiply it by 7% (a constant) to get your approximate power gain (example 35%). A rounding of 7% is used because 7% is approximately how much more air and fuel gets into the motor with each pound of boost that is added. To get a more exact figure, take 1 psi boost and divide by normal atmospheric pressure, 14.7 psi at sea level. 1 divided by 14.7 equals 6.802%. Under ideal conditions, the user can expect to burn 6.802% more fuel and air per pound of boost.
There are many ways to cool the air. In the present operating system, water is supplied from the water pump. There are also other style water coolers, mostly tube type where water runs through tubes cooling air in an enclosed chamber. A unique flat plate collector design is used because it offers more surface area for the water to cool the air in a smaller space, and offers the least amount of restriction in airflow. Less restriction equals more efficient horsepower gains.
Water Pump: The water pump is driven directly off the engine's crankshaft by a shaft that fits into a keyed slot in the end of the crankshaft connected to a centrifugal pump housing. This type of pump provides higher volume and can be run dry without pump failure.
The bell housing or transmission casing 20 is of one-piece design incorporating a rear mounting system 39 in the rear cover plate. The bell housing case 20 could be made of composite materials (such as fiberglass) internally reinforced with aluminum plates to hold bearing tolerances. Casing 20 could also be cast in aluminum.
Transmission gear sets: The transmission consists of 5 gears on 3 shafts and provides 4 different gear rations depending on gear size selections. There will be a forward set of gears, a reverse set of gears and a idler gear. Shifting between gears is achieved with a sliding clutch assembly, possibly assisted by a centrifugal designed clutch integrated with the flex plate to ease and smooth shifting.
It should be noted with respect to the engine accessories mounted on the integrated transmission bell housing, other possible engine accessories can be mounted on the bell housing with power take offs from the oil lubricated case. The gears discussed herein, including the gear on the flywheel, may be nitrided gears or carbon hardened gears. The bell housing referred to herein sometimes includes the transmission case.
The claims appended hereto are meant to cover modifications and changes within the scope and the spirit of the present invention.
This is a regular patent application based upon and claiming the benefit of provisional patent application Ser. No. 60/540,440 filed Jan. 30, 2004 and provisional patent application Ser. No. 60/542,148 filed Feb. 6, 2004.
Number | Name | Date | Kind |
---|---|---|---|
3263663 | Connell | Aug 1966 | A |
3386242 | Trapp | Jun 1968 | A |
4369384 | Nardi | Jan 1983 | A |
4666412 | Rawlings | May 1987 | A |
5058558 | Ueda et al. | Oct 1991 | A |
5326294 | Schoell | Jul 1994 | A |
5462465 | Schmidt | Oct 1995 | A |
5494466 | Vernea | Feb 1996 | A |
5530305 | Krueger et al. | Jun 1996 | A |
5761959 | Winter | Jun 1998 | A |
6095876 | Ozawa et al. | Aug 2000 | A |
6328004 | Rynhart | Dec 2001 | B1 |
6357399 | Nakamura | Mar 2002 | B1 |
6482057 | Schoell | Nov 2002 | B1 |
Number | Date | Country | |
---|---|---|---|
20050176313 A1 | Aug 2005 | US |
Number | Date | Country | |
---|---|---|---|
60540440 | Jan 2004 | US | |
60542148 | Feb 2004 | US |