Abstract:
A method of modifying the oil cooling system of a diesel engine includes the steps of removing the original equipment liquid-to-liquid heat exchanger and installing a manifold having a configuration adapted to match the mounting configuration of the oil passages of the original equipment liquid-to-liquid heat exchanger. The manifold has an oil outlet port directed to a remotely mounted oil cooler. The manifold also has a water passage having a configuration that is adapted to match the mounting configuration of the water passages of the original equipment liquid-to-liquid heat exchanger. The water passage causes the entirety of the flow of water to be discharged back to the water cooling system of the engine where it is circulated by the water pump through the water cooling passages in the engine.

Description:
FIELD OF THE INVENTION  
       [0001]    The present invention relates to a cooling system for an internal combustion engine and more particularly relates to an oil cooling system for both combustion ignition and diesel engines, collectively internal combustion (IC) engines. 
       BACKGROUND OF THE INVENTION 
       [0002]    Most internal combustion engines require a cooling circuit having a coolant pump, radiator and passageways which circulate a coolant from the radiator through the engine block to cool the engine block and the moving components in the engine block. Lubricants, typically a synthetic or mineral-based oil, are utilized to lubricate the relatively moving surfaces in the engine to counteract friction, reduce wear and reduce operating temperatures. 
         [0003]    However, excessive heat generated in the operation of the engine may cause the oil to degrade and break down losing its lubricating ability. When motor oils break down, they oxidize, thermally degrade and lose viscosity due to shear forces. As a result, many internal combustion engines, particularly high speed diesel engines and high performance combustion ignition engines, utilize engine block mounted oil coolers. Oil from the engine is passed through a cooler which operates as a heat exchanger with heat exchanger fluid, usually water and glycol, being provided from the engine cooling system from either the radiator or the engine block. 
         [0004]    However, since the opening temperature of the thermostat in cooling systems of most internal combustion engines is approximately in the range of 180° to 200° Fahrenheit, an oil cooler utilizing engine coolant as the heat exchanger fluid is limited in its ability to cool the engine oil. By the operation of the cooling system thermostat in many engines, an oil temperature of approximately 200° to 220° F. is maintained so that the oil effectively lubricates and does not break down or degrade. Further, a low oil temperature is preferred because the oil, in addition to being a lubricant, also serves to cool the internal combustion engine components. 
         [0005]    In a coolant to oil cooler system, the engine oil temperature is dependent upon the coolant supply. In the event of even a minor coolant loss, the engine may be damaged as the engine will incur the cooling loss provided both by the coolant and the engine oil. 
         [0006]    Accordingly, there exists a need for an improved coolant to oil cooler system for IC engines which obviates the deficiencies set forth above. 
       BRIEF SUMMARY OF THE INVENTION  
       [0007]    Briefly, the present invention provides a cooling system which replaces the conventional engine mounted coolant-to-oil heat exchanger with an external, high-capacity air-to-liquid heat exchanger. An adaptor block or manifold is configured to replace an existing Original Equipment Manufacturer (OEM) engine oil cooler and is mounted in place on the engine block utilizing the existing mounting and similar hardware and gaskets that secure the conventional engine oil cooler in place. 
         [0008]    The manifold is configured or ported with a passageway to receive the hot, unfiltered oil from the engine and directs the oil to a cannister-style oil filter of the type having a replaceable cartridge. The filter may be located immediately adjacent to the manifold or may be at a remote location within the engine compartment. Filtered oil from the oil filter is directed to an external heat exchanger, preferably a high-capacity air to liquid heat exchanger, which returns the cooled and filtered oil to the manifold which, in turn, returns cooled and filtered oil to the engine. The system may also include separate bypass filtration and a particle filtration screen within the manifold, as well as an oil bleeder valve and an anti-siphon valve. Suitable provision is made in the manifold for installation of sensors to measure engine operating parameters such as oil pressure and temperature. Further provision can be made for oil supply to an accessory such as a turbo charger. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The above and other advantages and objects of the present invention will become more apparent when taken in conjunction with the following description, claims and drawings in which: 
           [0010]      FIG. 1  is a schematic representation of an embodiment of a cooling system according to the present invention; 
           [0011]      FIG. 2  is a detailed perspective view of the adaptor or manifold section of the cooling system shown in  FIG. 1 ; 
           [0012]      FIG. 3  is a plan view of the bottom of the manifold showing a representative  5  mounting configuration which is adapted to replace the conventional OEM oil cooler; 
           [0013]      FIG. 4  is a cross-sectional view of a section of the manifold illustrating the air bleed valve; 
           [0014]      FIG. 5  is a schematic view of an engine oil by-pass that may be incorporated into the cooling system; 
           [0015]      FIG. 6  is a schematic view showing the oil by-pass of  FIG. 5  incorporated in the system of  FIG. 1 ; and 
           [0016]      FIG. 7  is a schematic showing a modified system as shown in  FIG. 6  further including both coolant-to-oil and air-to-oil heat exchangers with by-pass features to provide warming of the engine oil upon start-up. 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Turning now to the drawings,  FIG. 1  shows the cooling system of the present invention mounted in place on the cylinder block B of an IC engine which is represented schematically by dotted lines. The mounting location may vary depending on the engine configuration. The IC engine may be a CI or diesel having an engine mounted cooler  8  which is removed and replaced with a manifold  11 . The system indicated by the numeral  10  includes a housing or manifold  11  which may be cast and machined from a single block or billet of material such as steel or aluminum. Preferably the underside of the manifold, as best seen in  FIG. 3 , is machined to conform to the mounting configuration of the conventional coolant-to-oil cooler mounted on the engine block which cooler has been removed, having bolt holes  19  conforming to the existing bolt pattern.  FIG. 3  shows a representative  5  mounting for a 6.0L International® VT365 diesel engine also known as the 6.0L Ford® Powerstroke diesel engine (hereinafter referred to as the “6.0L VT365 diesel engine”) found in a 2004 Ford F350 truck. If the engine has not been originally equipped with an oil cooler, suitable mounting provision for the manifold must be made which may involve appropriate modifications such as tapping the engine block at suitable locations for mounting the manifold and installing suitable hydraulic lines. 
         [0018]    However, in most cases, the cooling system of the present invention will be applicable and is adapted for replacement of a conventional engine mounted IC coolant-to-oil cooler and the following description proceeds on that basis. Once the existing oil cooler is removed, the manifold  11  is secured using suitable hardware and gaskets to position and mount the housing on the engine block B. Port or passageway  25  in the underside of the manifold aligns with a port P in the engine block B through which hot, unfiltered oil is directed to the manifold  11 . The oil enters the manifold at passageway  25  and flows through the manifold  11  exiting at port  13 . Port  13  is connected by a hydraulic line  20  to oil filter  14 . Line  20  has an anti-siphon check valve  21  to prevent reverse flow of oil through line  20 . The oil filter  14  may be located immediately adjacent the manifold  11  or may be at a convenient location in the engine compartment considering engine size, available space and other installation restrictions. 
         [0019]    The oil filter  14  is a canister-type and has an inlet  22  which communicates with and receives oil from the manifold. The housing has a lower screw or spin-on body  24  which is removable. The body  24  contains a suitable element  26  of a filtering material such as paper or fiber which is periodically replaceable. Preferably the filter is a conventional filter available from manufacturers such as FRAM, WIX and others. Particulates and contaminants are substantially removed as the oil passes through the filter element  26 . 
         [0020]    The oil exiting oil filter  14  is then directed to an external heat exchanger, preferably an air-to-liquid heat exchanger  15 . The external heat exchanger may be a tube or plate design and is preferably of the tube type having a tube  28  carrying the oil to be cooled which extends in serpentine fashion within the heat exchanger housing. Because air is a relatively poor conductor of heat, the heat transfer area between the air passing over the tubes is increased by adding fins  30  to the tubes. The heat exchanger  15  is mounted in a location remote from the location of the OEM heat exchanger, preferably located in the vehicle to receive substantial airflow, for example at the front of the vehicle immediately adjacent and in front of the radiator for the engine cooling system. Ducting may be provided to increase airflow to the heat exchanger  15 . 
         [0021]    The oil which has been cooled and filtered is returned to an inlet port  17  on the manifold  11  via line  32 . The inlet port  17  connects with internal passageway  34  communicating with outlet port  12 . The outlet port  12  on the bottom of the manifold is aligned and communicates with the engine block port P so the cooled and filtered oil returns to the engine to provide lubrication. An additional outlet port  12 A, as seen in  FIG. 3 , is provided to supply cooled and filtered oil to the high pressure oil pump. 
         [0022]    Additional filtering may be provided by a bypass filter  18 . The bypass filter  18  is a separate filter and may be of the cannister type as described with reference to filter  14 . A bypass line  36  removes a portion of the cooled and filtered oil prior to the oil entering into port  17  and directs the oil to the inlet of the bypass filter  18 . The bypass filter  18  has an outlet which directs the flow via line  38  to port  12  to be returned to the engine  5 . 
         [0023]    Passageway  34  connected to port  17  may also be intercepted by passageways  40 ,  42  and  44  which are suitably threaded for connection to gauges such as the pressure gauge at  40 , temperature gauge  42  and oil feed for the turbo at  44 . Other sensing locations can also be provided to measure other operating parameters. Provision is made in the manifold to circulate coolant through the engine cooling system. Coolant enters the manifold at port  55  and exits at port  56  where it is returned to the engine cooling system without passing through the external heat exchanger  15 . The coolant thus returned to the engine cooling system is circulated by a water pump through the existing passages in the engine block and radiator. 
         [0024]    In many engines, metal particles will be released during operation. In addition to metal particles, sand used in the engine block casting process and retained in the engine may also be released. These larger, particulate materials can be harmful to the engine and may also quickly clog or reduce the effectiveness of the filters, such as the F1A filter, which are primarily intended to remove finer particulate materials. 
         [0025]    The oil cooling system of the present invention may be provided with a particulate filter internal within the manifold  11  to trap and remove larger particulates which may otherwise quickly impair the effectiveness of element type filters. A cavity  50  is provided within the housing and removably receives a screen  52  having a mesh in the 0.003 to 0.005 inch range. The screen is accessible and removable by detaching the manifold from the engine block or access may be provided through a suitable access panel  54  on the manifold. A portion of the cooled and filtered oil entering the manifold at port  17  may be internally diverted to the cavity  50  and onto a surface of the particulate screen  52 . The oil will, due to pressure existing in the system and gravity, flow downwardly through the screen to ports  12  and  12 A returning to the engine. Particulate material will collect on the screen  52  and may be periodically removed by accessing the screen by removal of the manifold or through an access panel as described above. 
         [0026]    An oil bleed valve  16  may be provided as seen in  FIG. 4 . The oil bleed valve  16  is in a passageway  60  communicating with passageway  34 . A ball  65  is held in place by a spring  66 . The spring  66  is retained by a plug  68  with a small orifice  70 . Passageway  60  is closed by a plug  72 . When the pressure in passageway  34  exceeds a predetermined level, the ball  65  will open returning oil to the engine crank case via line  62 , allowing air within the engine&#39;s oil system to be removed. 
         [0027]      FIGS. 2 and 3  illustrate a representative configuration for the manifold and for the configuration of the passageways within the manifold which may be utilized in connection with the cooling system of the present invention. However, it will be appreciated that the particular configuration shape of the manifold may vary with the intended installation. It will also be appreciated that the present system has broad utility and application to various internal combustion engines of different types and displacement. Accordingly, while the present invention has been described in detail with reference to a preferred embodiment it is to be understood that the disclosure has only illustrated an exemplary embodiment. 
         [0028]      FIGS. 5 and 6  are schematics which show a by-pass  100  that may be incorporated into the system  10  shown in  FIG. 1 . Referring to  FIG. 5 , which  5  shows the by-pass  100  which has a housing  102  having an inlet  106  and outlet  108  connected by a passageway  110  is intercepted by a pressure by-pass line  112  and a temperature by-pass line  114  both of which communicate with by-pass outlet  120 . A pressure control valve  122  such as a spring-biased valve is located in line  112 . The valve  122  may be a direct acting relief valve which opens at a fixed pre-set pressure established by a spring which may be adjusted by a spring adjustment screw. The valve is set to by-pass fluid to the outlet when the differential pressure between the inlet and outlet of the oil cooler is above the setting, typically about 40-50 psi, which differential may initially occur during start-up before the pressure in the system generated by the engine oil pump has fully pressurized the engine oil system. 
         [0029]    Similarly, the temperature by-pass line includes a thermostatic control  126  which has a selected opening temperature generally between 170-200° F. The thermostat control will block flow through the by-pass  100  and direct the oil flow to outlet  120  until such time as the temperature of the oil reaches a temperature at which the thermostat is set to open. Thus, the oil entering the by-pass  100  will be directed to the cold by-pass outlet  120  if either: (1) the engine oil is below a predetermined temperature by the closed thermostat  126  or (2) the oil pressure differential between the inlet and outlet of the oil cooling heat exchanger  15  is greater than the differential setting of the control valve  122 . 
         [0030]    In  FIG. 6 , the by-pass  100  is shown in the system  10  of  FIG. 1 . The system  10  has been simplified in  FIG. 6  but is as described in greater detail with reference to  FIG. 1  which description is incorporated here by reference. The by-pass  100  is located adjacent the air-to-liquid heat exchanger  15 , either ahead of the heat exchanger  15  or downstream of the discharge. In  FIG. 6 , the by-pass  100  is shown ahead of the heat exchanger  15 . The outlet  108  of the by-pass  100  is in communication with the heat exchanger  15 . The by-pass outlet  120  is connected via by-pass line  130  to line  32  leading to the manifold  11 . Accordingly, if engine oil is below a predetermined temperature or if a predetermined pressure differential exists between the inlet and outlet of oil exceeding the setting of control valve  122 , oil will be by-passed through by-pass  100  allowing the system oil temperature and pressure to build to acceptable levels due to engine operation. This typically may take 4 or 5 seconds after start up. The by-pass  100  lessens stress and wear on engine components due to oil conditions which reduce the effectiveness of the lubrication. 
         [0031]    In  FIG. 7 , a modification of the system  10  of claim  1  is shown which is adopted for engines which operate in colder climates. They system of  FIG. 7  is indicated by the numeral  200  and includes a manifold  11  secured to the engine block B as described with reference to  FIG. 1 . The hot, unfiltered oil from the engine is directed to a filter  14  by line  20  and exits the filter  14  to tee  202  having outlet lines  232 ,  232 A. Line  232  is directed to by-pass  100  located adjacent an air-to-liquid heat exchanger  15 . The by-pass  100  is as described with reference to  FIGS. 5 and 6 . The heat exchanger  15  is as has been previously described with reference to  FIG. 1 . The by-pass  100  will direct engine oil either to the heat exchanger  15  or, if the temperature or pressure conditions of the oil are within predetermined by-pass parameters, the oil will be by-passed around the heat exchanger  15  via line  130  to line  32 . 
         [0032]    The engine oil discharged through line  232 A is directed to a coolant-to-oil heat exchanger  225  which receives liquid coolant at inlet port  226  from the engine cooling system under pressure from the engine water pump  230  which is recirculated from the heat exchanger via line  234 . The thermostat in the engine cooling system will operate at a preset opening temperature of typically around 190°-200° F. and be circulated by the water pump  230  through the heat exchanger  225  to warm the oil initially flowing through the heat exchanger from the filter. As the engine warms and the engine oil is heated, the heat exchanger  225  will operate to maintain the oil temperature at about the temperature of the engine coolant fluid from the water pump. Thus, the heat exchanger initially assists in heating the engine oil during the initial engine start-up and thereafter will operate to maintain the oil at an acceptable temperature. 
         [0033]    The dual system of  FIG. 7  having both an air heat exchanger and a liquid heat exchanger in parallel enhances or increases the effective heat exchange area and operates to cool engine oil during operation and will heat or warm the engine oil during initial start-up and has particular application to engines operating in colder climates or conditions. 
         [0034]    It will be obvious to those skilled in the art to make various changes, alterations and modifications to the invention described herein. To the extent such changes, alterations and modifications do not depart from the spirit and scope of the appended claims, they are intended to be encompassed therein.