Abstract:
An heat exchanger assembly and a method of use thereof adapted for transferring heat to or from a fluid to a surrounding environment within an apparatus, such as motor vehicle engines, as it enters and leaves a fluid-handling device. The heat exchanger assembly includes first and second manifolds, multiple cooling tubes and a return tube. The first manifold has inlet holes therein and the second manifold has outlet holes therein. The multiple cooling tubes fluidically interconnect the first and second manifolds and the inlet and outlet holes thereof. The return tube passes through the first and second manifolds to fluidically interconnect opposite ends of the heat exchanger assembly. The return tube has a first end adapted to mount the heat exchanger assembly to the apparatus and an oppositely-disposed second end that protrudes from the second manifold and is adapted to secure the fluid-handling device thereto.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/527,806, filed Aug. 26, 2011, the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention generally relates to heat transfer apparatuses. More particularly, this invention relates to an heat exchanger assembly adapted for installation on an apparatus, such as motor vehicle engines, to cool oil as it enters and leaves an fluid-handling device. 
         [0003]    Heat exchangers are routinely employed within the automotive industry, such as in the form of radiators for cooling engine coolant, oil coolers, charge air coolers, condensers and evaporators for air conditioning systems, and heaters. In order to efficiently maximize the amount of surface area available for transferring heat between the environment and a fluid flowing through the heat exchanger, heat exchanger designs are typically of a tube-and-fin type in which numerous cooling tubes thermally communicate with high surface area cooling fins. The cooling fins enhance the ability of the heat exchanger to transfer heat from the fluid to the environment, or vice versa. 
         [0004]    Oil coolers for automotive vehicle engine systems typically include a pair of headers and a core having a plurality of cooling tubes disposed between the two headers. A heated oil from a transmission flows through the cooling tubes and air flowing through a grill of the vehicle flows across the cooling tubes in order to remove heat from the oil within the cooling tubes. The oil enters and exits the oil cooler through the headers. The headers are typically connected to the engine and the oil filter by hoses and connectors, such as clamps. 
         [0005]    Oil coolers of the type described above may be difficult to install. Typically, a plurality of metal brackets are welded to a vehicle frame and the oil cooler is attached thereto by threaded fasteners. Disadvantageously, welding requires additional processing steps during vehicle assembly. Further, conventional mounting arrangements typically require multiple threaded fasteners to assure a secure mount. In many instances, the threaded fasteners may work lose which may result in vibration. In addition, the fasteners can be over-tightened and may result in damage to the oil cooler. 
         [0006]    Once the oil cooler is mounted, the hoses must be run to the headers of the oil cooler. This requires additional installation steps and clutters the area around the engine. Because oil pressure drops within a hose as the length of the hose increases, the oil cooler may have a negative impact on the performance of the vehicle depending on the location of the mounted oil cooler. 
         [0007]    In view of the above, it can be appreciated that there is a need for an improved heat exchanger assembly for cooling oil within an engine of a motor vehicle, as well as other types of fluid-containing apparatuses. It would be particularly advantageous if such heat exchanger assembly were capable of installation without mounting fixtures to secure the heat exchanger or hoses to transfer the oil between the heat exchanger and components of the engine. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0008]    The present invention provides a cooler assembly and a method of use thereof adapted for cooling oil within an apparatus, including but not limited to motor vehicle engines. 
         [0009]    According to a first aspect of the invention, a heat exchanger assembly includes first and second manifolds, multiple cooling tubes and a return tube. The first manifold has inlet holes therein and the second manifold has outlet holes therein. The multiple cooling tubes fluidically interconnect the first and second manifolds and the inlet and outlet holes thereof. The return tube passes through the first and second manifolds to fluidically interconnect opposite ends of the heat exchanger assembly. The return tube has a first end adapted to mount the heat exchanger assembly to an apparatus and an oppositely-disposed second end that protrudes from the second manifold and is adapted to mount a fluid-handling device thereto. 
         [0010]    According to a second aspect of the invention, a method is provided for transferring heat to or from a fluid to a surrounding environment using a exchanger assembly. The heat exchanger assembly includes first and second manifolds, multiple cooling tubes and a return tube. The first manifold has inlet holes therein and the second manifold has outlet holes therein. The multiple cooling tubes fluidically interconnect the first and second manifolds and the inlet and outlet holes thereof. The return tube passes through the first and second manifolds to fluidically interconnect opposite ends of the heat exchanger assembly. The return tube has a first end adapted to mount the heat exchanger assembly to an apparatus and an oppositely-disposed second end that protrudes from the second manifold and is adapted to mount a fluid-handling device thereto. The method includes mounting the first end of the return tube of the heat exchanger assembly to the apparatus, mounting at least a first fluid-handling device to the second end of the return tube of the heat exchanger, and then operating the apparatus causing the fluid to flow from the apparatus, through the inlet holes and the cooling tubes of the heat exchanger assembly where the fluid is cooled therein, through the outlet holes into the fluid-handling device, through the return tube and back into the apparatus. 
         [0011]    A technical effect of the invention is the ability to cool oil within an apparatus, such as motor vehicle engines, without the need for complicated mounting fixtures or additional hoses by utilizing a compact oil cooler that can be mounted in-line. 
         [0012]    Other aspects and advantages of this invention will be better appreciated from the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view representing an in-line heat exchanger assembly comprising multiple finned cooling tubes between a pair of headers in accordance with an aspect of this invention. 
           [0014]      FIG. 2  is a side view of the heat exchanger assembly of  FIG. 1 . 
           [0015]      FIG. 3  is a cross-sectional view representing the heat exchanger assembly of  FIG. 2  taken along section line A-A, but with the cooling fins omitted to promote the clarity of the view. 
           [0016]      FIG. 4  is a cross-sectional view similar to the view shown in  FIG. 3 , but with the cooling fins included. 
           [0017]      FIG. 5  is a cross-sectional view representing the heat exchanger assembly of  FIG. 4  taken along section line B-B. 
           [0018]      FIG. 6  is an isolated side view representing one of the cooling tubes of  FIG. 1  and multiple cooling fins mounted thereon in accordance with an aspect of this invention. 
           [0019]      FIG. 7  is a top view representing one cooling fin of the multiple cooling fins of  FIG. 6  in accordance with an aspect of this invention. 
           [0020]      FIG. 8  is a perspective view representing the heat exchanger assembly in position between an oil filter and a wall of an apparatus in accordance with an aspect of this invention. 
           [0021]      FIG. 9  is a side view representing the heat exchanger assembly of  FIGS. 1 through 8  adapted for use with a coolant in accordance with an aspect of this invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]      FIGS. 1 through 9  represent nonlimiting examples of a heat exchanger  10  according to embodiments of the present invention. The heat exchanger  10  is adapted to be mounted on an engine or other apparatus through which a fluid flows and adapted to mount and fluidically connect a fluid-handling device to the apparatus. Such apparatuses include, but are not limited to, engines for automobiles, recreational vehicles, motorcycles, boats, lawn mowers, etc., compressors, or hydraulic units, as well as various types of assemblies in which cooling or heating of a fluid within the assembly is desired. An example of the fluid-handling device is an oil filter. The heat exchanger  10  is adapted to transfer heat to or from the fluid from the environment. In the case of an automobile engine and oil filter, the heat exchanger  10  is configured to allow oil cooling capabilities within an engine without reliance on additional hoses or mounting fixtures, such as those required by types of oil coolers known in the art. 
         [0023]    To facilitate the description of the heat exchanger  10  provided below, the terms “top,” “bottom,” “side,” “upper,” “lower,” “above,” “below,” “right,” “left,” etc., will be used in reference to the perspective of the orientation shown in  FIGS. 1 through 9 , and therefore are relative terms and should not be otherwise interpreted as limiting the scope of the invention. 
         [0024]      FIGS. 1 and 2  are perspective and side views representing the heat exchanger  10 , respectively.  FIGS. 3 and 4  are cross-sections of the heat exchanger  10  taken along section line A-A of  FIG. 2 , showing the heat exchanger  10  without and with cooling fins  24 , respectively. As labeled in  FIGS. 1 through 4 , the heat exchanger  10  is an assembly comprising a filter flange  12 , top cooler manifold  14 , bottom cooler manifold  16 , a mounting flange  18 , a central return tube  20 , cooling tubes  22  surrounding the return tube  20 , cooling fins  24  on the cooling tubes  22 , and a gasket  26  (only shown in  FIG. 3 ) for sealing the mounting flange  18  against a mounting surface, such as an engine block.  FIG. 5  is a cross-section of the heat exchanger  10  taken along section line B-B of  FIG. 4 , and represents the heat exchanger  10  as having six cooling tubes  22  each with multiple cooling fins  24  mounted thereon.  FIG. 6  represents one of the cooling tubes  22  with cooling fins  24  mounted thereon.  FIG. 7  is a top view representing one of the cooling fins  24  from  FIG. 6 . As represented in  FIGS. 6 and 7 , the cooling fins  24  may have a corrugated cross-sectional shape and a continuous circular-shaped outer perimeter. Other fin shapes are also within the scope of this invention. Furthermore, it is foreseeable that the heat exchanger  10  can be configured to operate without the use of cooling fins  24 , to have any number of cooling fins  24 , to have any number of cooling tubes  22 , and to have cooling tubes  22  that are formed to have shapes other than straight tubes having round cross-sections. 
         [0025]    As evident from  FIG. 3 , oil is able to enter the bottom cooler manifold  16  through inlet holes  28  in the gasket  26  and mounting flange  18 , pass through the cooling tubes  22  before entering the top cooler manifold  14 , and then exit the heat exchanger  10  through outlet holes  42  in the filter flange  12 . Oil exiting the heat exchanger  10  in this manner may subsequently flow through, for example, an oil filter  30 , as represented in  FIG. 8 . After flowing through a filtering media of the filter  30 , the oil is returned to an engine  32  (a wall portion of which is shown) through the return tube  20 . For use in combination with the oil filter  30 , the return tube  20  can be adapted to serve as a fastener for the heat exchanger  10 . In preferred embodiments of the invention, an exterior of one end of the tube  20  is preferably threaded to threadably accept the oil filter  30 , and an interior of an opposite end of the return tube  20  is preferably threaded to accept a mounting stud  34  of a type that is conventionally provided on the engine  32  to mount the filter  30  in the absence of the heat exchanger  10 . 
         [0026]    As represented in  FIG. 3 , the cooling tubes  22  can have dimples  36  or other surface features to create turbulence within oil flowing through the cooling tubes  22 . Heat transfer from the oil within the cooling tubes  22  to the surrounding environment is promoted by the cooling fins  24 , which are stacked onto each tube  22  to define an axial fin stack. The cooling fins  24  can be secured to the cooling tubes  22  by diametrically expanding the cooling tubes  22  by such hydraulic expansion methods or other suitable means. The cooling tubes  22  and cooling fins  24  can then be assembled with the manifolds  14  and  16  by inserting ends of the cooling tubes  22  into appropriately sized holes formed in the manifolds  14  and  16 . Similarly, the return tube  20  is inserted through the manifolds  14  and  16 , after which the filter flange  12  and mounting flange  18  can be assembled to the return tube  20  and secured to the manifolds  14  and  16  to close and seal the manifolds  14  and  16 . Known brazing and soldering techniques can be employed to join components of the heat exchanger  10 . The gasket  26  can then be secured to the mounting flange  18  to result in the construction shown in  FIGS. 1 through 8 . 
         [0027]    An alternative to the embodiment described above is to enclose the cooling tubes  22  and cooling fins  24  between the manifolds  14  and  16 , and then flow a coolant, for example, a liquid such as water or antifreeze, through a resulting cavity.  FIG. 9  is a side view representing the heat exchanger  10  further comprising a jacket  38  enclosing the cooling tubes  22  and cooling fins  24 . The heat exchanger  10  may include at least a fitting  40  or other similar features that serve as one or more inlets and outlets through which the coolant flows into and out of a cavity (not shown) defined by the jacket  38  between the manifolds  14  and  16 . Such embodiment may be preferable in applications requiring high heat transfer rates. Modifications to the heat exchanger  10  may be necessary or preferable when coolant is utilized. For example, higher heat transfer rates may allow the removal of the cooling fins  24  or fluid dynamics of the coolant may require the cooling fins  24  to be formed with a different shape. 
         [0028]    To install the heat exchanger  10  in-line with the oil filter on the engine  32 , the oil filter  30 , if present, is removed from the mounting stud  34  of the engine  32 . The heat exchanger  10  is then mounted directly to the mounting stud  34 , and thereafter the oil filter  30  is mounted to the heat exchanger  10  so that the cooler  10  is between the engine  32  and the oil filter  30 . As previously discussed, one end of the return tube  20  is preferably adapted to threadably mount the heat exchanger  10  to the engine  32  and an oppositely-disposed second end that protrudes from the second manifold  16  is adapted to threadably secure the oil filter  30  thereto. 
         [0029]    A single heat exchanger  10  can be used, or additional heat transfer capacity can be achieved by simply mounting multiple heat exchangers  10  to each other in series. In this situation, the first end of the return tube  20  of the heat exchanger  10  is adapted to threadably mount to the second end of the return tube  20  of an additional heat exchanger  10 . Therefore, to install multiple heat exchangers  10 , the first end of the return tube  20  of the heat exchanger  10  is mounted to the engine  32 . Next, one or more additional heat exchangers  10  are installed by securing the first end of the additional heat exchangers  10  to the second end of previously installed heat exchangers  10 . Once all heat exchangers  10  have been installed, the oil filter  30  is secured to the second end of the heat exchanger  10  that was last to be installed. Upon operation of the engine  32 , oil flows through the inlet holes  28 , cooling tubes  22  and outlet holes  42  of each heat exchanger  10  into the oil filter  30  in the same fashion as if only a single heat exchanger was present. After flowing through the filtering media of the filter  30 , the oil is returned to the engine  32  through the return tubes  20  of all the oil assemblies  10 . 
         [0030]    Axial lengths of the cooling tubes  22  can be tailored to achieve desired attributes of the heat exchanger  10  for a particular application. For example, the length of the cooling tubes  22  may be extended to improve heat transfer capability. Conversely, the cooling tubes  22  can be shortened to offer minimal oil pressure drop within the heat exchanger  10 . 
         [0031]    The heat exchanger  10  represented in  FIGS. 1 through 9  offers various advantages. The heat exchanger  10  reduces the temperature of engine oil as it passes to and from the oil filter  30 . Heat transfer is promoted through the use of multiple cooling tubes  22  and their cooling fins  24 . Installation and removal of the heat exchanger  10  are as uncomplicated as changing the oil filter  30 , and the heat exchanger  10  is preferably adapted to be mounted to an existing mounting surface of the engine  32 . 
         [0032]    While the invention has been described in terms of specific embodiments, it is apparent that other forms could be adopted by one skilled in the art. For example, the physical configuration of the heat exchanger  10  could differ from that shown, and materials and processes other than those noted could be used. Therefore, the scope of the invention is to be limited only by the following claims.