Patent Abstract:
A turbocharger system for an internal combustion engine includes a turbocharger with a utility pedestal extending between the turbocharger and the hard point associated with the cylinder block. The utility pedestal includes a mounting pad for attaching the combined turbocharger and pedestal assembly to an engine, as well as oil and coolant supply passages for supplying the turbocharger with coolant and lubricating oil under pressure. An internal, isolated, turbocharger oil drainback passage conducts waste oil from the turbocharger to a crankcase sump without permitting the waste oil to contact the engine&#39;s moving parts.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    None. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a turbocharger system including not only a turbocharger, but also a mounting pedestal arranged with utilities needed to operate and position the turbocharger, including an internal, isolated turbocharger lubricating oil drainback passage. 
         [0004]    2. Related Art 
         [0005]    Turbocharging has been used for a number of years with internal combustion engines. Although early turbochargers were often cooled primarily by air, as well as by the flow of oil through the turbocharger&#39;s bearings, later model turbochargers, especially larger turbochargers and those installed in heavy duty engines, generally utilize coolant circulating from the engine&#39;s cooling system through the turbo, and then back to the engine&#39;s main cooling system. Of course, turbochargers also require an oil supply and drain utilities to lubricate the bearings associated with the turbocharger. Needless to say, the provision of a source of coolant and a source of oil, with both being under pressure, as well as draining the oil and coolant from the turbocharger and returning these fluids separately to the engine, has necessitated a good deal of external plumbing. Unfortunately, external fluid connections and associated pipes and hoses cause problems because hoses are known to leak and are subject to damage which may be accelerated by the high temperatures prevailing within engine compartments. Moreover, aside from durability issues, the need for external plumbing for turbochargers increases the space required by the turbocharger in an already crowded underhood environment. 
         [0006]    Turbochargers mounted on engines typically consume a good deal of space for another reason. Because known mounting arrangements are not susceptible to locating the turbocharger close to the engine block, turbochargers must be spaced away from the engine to permit the insertion of the turbochargers&#39; fasteners. Moreover, known turbocharger mounting systems increase radiated noise because of a lack of rigidity and because of the dimensional problems associated with their usage. 
         [0007]    It would be desirable to provide a turbocharger, including a mounting system having integral supply and return passages for coolant and lubricating oil, and with the lubricating oil return passage being routed to enhance the effectiveness of the engine&#39;s lubrication system. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0008]    According to an aspect of the present invention a turbocharger system for an internal combustion engine having a cylinder block includes a turbocharger and a utility pedestal extending between the turbocharger and a mounting associated with the engine. The utility pedestal includes a mounting pad for the pedestal and an oil supply passage for conveying lubricating oil under pressure from a portion of the engine, such as the cylinder block, to the turbocharger. A return oil passage conveys lubricating oil from the turbocharger to a lubrication system incorporated within the engine. A coolant supply passage conveys coolant under pressure to the turbocharger, and a coolant return passage, configured at least in part within the utility pedestal, conveys coolant from the turbocharger to a cooling system incorporated within the engine. According to another aspect of the present invention, the coolant return passage may include a passage configured, at least in part, within the engine&#39;s cylinder block, as well as within the utility pedestal. 
         [0009]    According to another aspect of the present invention the coolant return passage from the turbocharger may be configured so as to convey the coolant to a mixing chamber within which the coolant from the turbocharger is mixed with coolant flowing from at least one cylinder head. 
         [0010]    According to another aspect of the present invention, the return oil passage from the turbocharger conveys waste oil from the turbocharger to a crankcase sump without allowing the waste oil to contact moving parts within the engine. 
         [0011]    According to another aspect of the present invention least a portion of the turbocharger return oil passage is configured from parent metal within the engine&#39;s cylinder block. 
         [0012]    According to another aspect of the present invention, a hard point associated with the cylinder block for mounting the turbocharger includes a generally planar mounting pad configured on a portion of the cylinder block, with the mounting pad of the utility pedestal having a lower mating surface matched to the generally planar mounting pad. The cylinder block&#39;s mounting pad is configured with lubricating oil and coolant utilities. 
         [0013]    According to another aspect of the present invention, a turbocharger&#39;s generally planar mounting pad may be configured upon a cylinder block within a valley defined by the cylinder banks of a V-block engine. 
         [0014]    According to yet another aspect of the present invention, the turbocharger pedestal mounting pad of the utility pedestal comprises a number of mounting bosses having fastener bores extending therethrough at an acute angle with respect to horizontal plane such that fasteners inserted within the bores pass inboard to threaded bores formed in the hard point associated with the cylinder block. 
         [0015]    According to another aspect of the present invention, the return, or waste, oil passage extending from the turbocharger and through the utility pedestal is designed to prevent foamed or frothed oil flowing from the turbocharger from impairing engine lubrication. This is accomplished by preventing the waste oil from contacting moving parts within the engine as the oil flows back to the crankcase sump. Stated another way, the return oil passage is routed such that contact between waste oil flowing from the turbocharger and moving parts of the engine is minimized prior to de-aeration of the waste oil. 
         [0016]    It is an advantage of the present turbocharger system that the life of an engine to which the present turbocharger and pedestal are assembled will have enhanced useful life because the waste oil leaving the turbocharger is not permitted to come into contact with moving parts within the engine before de-aeration in the engine&#39;s lubrication system. 
         [0017]    It is another advantage of a turbocharging system according to the present invention that the turbocharger system, including the turbocharger and the utility pedestal, with its oil and coolant utilities, is compact and ideally suited for mounting in the valley of a V-block internal combustion engine. 
         [0018]    It is yet another advantage of a turbocharging system according to the present invention that the noise signature of the turbocharger will be reduced because of the stiffness inherent with the close mounted utility pedestal featured in the present invention. 
         [0019]    It is yet another advantage of the present invention that the fasteners used to mount the pedestal to the engine may be accessed without removing portions of the turbocharger. 
         [0020]    Other advantages, as well as features of the present invention, will become apparent to the reader of this specification. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is an exploded perspective view of an engine having a turbocharger system according to the present invention. 
           [0022]      FIG. 2  is an end view, partially cut away, of a portion of an engine having a turbocharger system according to the present invention. 
           [0023]      FIG. 3  is a plan view of an engine block showing a turbocharger pedestal mounting pad and utility passages for lubricating oil and coolant according to an aspect of the present invention. 
           [0024]      FIG. 4  is a side elevation, partially cut away, of an engine having a turbocharger system according to the present invention and showing the routing for several of the utility passages for oil and water according to the present invention. 
           [0025]      FIG. 5  is a side perspective view, partially cut away, of an engine having a turbocharger system according to the present invention. 
           [0026]      FIG. 6  is a perspective view of a turbocharger mounting hard point configured as a plate suitable for bolting or welding to an engine cylinder block. 
           [0027]      FIG. 7  is a plan view of an isolated turbocharger oil drainback passage, taken along the line  7 - 7  of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0028]    As shown in  FIG. 1 , turbocharger system  10  includes a turbocharger,  14 , and a utility pedestal  18 . Turbocharger  14  is preferably mounted to utility pedestal  18  before turbocharger  14  is mounted upon an engine.  FIG. 1  also shows a metallic cylinder block,  30 , having a valley,  20 , into which turbocharger system  10  is placed upon a hard point, which is illustrated as generally planar mounting pad  22 . Utility pedestal  18  provides rigid structural support for turbocharger  14 ; this helps to reduce unwanted engine noise emissions, as well as reducing unwanted vibration associated with the turbocharger. Those skilled in the art will appreciate in view of this disclosure that the term “hard point”, as used herein means either a structurally rigid mounting location such as block pad machined into the parent metal of a cylinder block, or a separate pad or bracket, such as that illustrated at  100  in  FIG. 6 . Mounting pad  100  is intended to be attached to an engine by bolting, or welding, or by some other suitable process. 
         [0029]    Utility pedestal  18  has a mounting pad,  48 , at its lower extremity. Mounting pad  48  includes mounting bosses  50 , which have fastener bores  52 . Fastener bores  52  extend through mounting bosses  50  and make an acute angle, α, with a horizontal plane, H ( FIG. 1 ). Fastener bores  52  allow the passage of a number of threaded fasteners,  56 , which pass through fastener bores  52  and into threaded bores,  28 , formed in generally planar mounting pad  22  of cylinder block  30 . Two of threaded bores  28  are shown in  FIG. 1 .  FIG. 1  further shows that mounting bosses  50  are angled so that threaded fasteners or bolts  56  extend inboard into bolt holes  28  formed in mounting pad  22  of cylinder block  30 . This geometry is also shown in  FIG. 2 . 
         [0030]    As seen in  FIG. 2 , the width, A, of utility pedestal mounting pad  48  is less than the overall width, B, of turbocharger  14 . This is an added benefit stemming from the angular orientation of fastener bores  52 , which fortuitously permit turbocharger  14  and utility pedestal  18  to be disassembled as one unit from the engine without removing portions of the turbocharger assembly. The angles of fastener bores  52  also allow turbocharger  14  to be mounted closer to cylinder block  30 , in a vertical direction closer to crankshaft  16 .  FIG. 2  shows turbocharger  14  nestled in valley  20  between cylinder heads  38  and cylinder block  30 . 
         [0031]      FIG. 3  shows generally planar mounting pad  22  as being located in the mid-portion of the valley of cylinder block  30 . Several of threaded mounting bolt holes  28  are shown.  FIG. 3  further illustrates several utilities for turbocharger  14 . The first such utility, oil supply passage  26 , is shown as terminating in a port formed within the planar surface of mounting pad  22 . Coolant supply passage  42  also communicates with this surface, as does coolant return  46 . In other words, portions of oil supply passage  26 , coolant supply passage  42 , and coolant return passage  46  are all co-planar with the uppermost surface of mounting pad  22 . As a result, all of these utilities may be sealed to utility pedestal  18  with a single gasket  24 , which is shown in  FIG. 1 . Gasket  24  is illustrated as a unitary carrier incorporating a number of integral o-rings for sealing passages  26 ,  42 , and  46 . 
         [0032]    Only the uppermost part of return oil isolation passage  34  within cylinder block  30  is shown in  FIG. 3 ; for more definition, one must look to  FIG. 4 , wherein return oil passage  34  is shown as leading to one end of engine block  30  and down into crankcase sump  98  through a route in which there are no rotating or moving parts. As noted above, the drainback of waste oil from turbocharger  14  to crankcase sump  98  through areas of the engine devoid of moving parts prevents galling or overheating of such moving parts by preventing contact between parts needing lubrication and temporarily aerated oil flowing from turbocharger  14 . Those skilled in the art will appreciate in view of this disclosure that oil return passage  34  may be configured either from the parent metal of cylinder block  30 , as a cored or machined passage through cylinder block  30 , as shown in the various figures, or as a fabricated passage, or both, so as to take advantage of available space and material within cylinder block  30 , while adding only a minimum number of components. Those skilled in the art will further appreciate that the term “waste oil”, as used herein, means lubricating oil which has been furnished to turbocharger  14  and is then returned to the crankcase sump for re-use. 
         [0033]      FIGS. 4 and 5  show oil supply passage  26  extending up into utility pedestal  18  from within cylinder block  30 . Further,  FIG. 5  shows coolant supply passage  42 , which extends into utility pedestal  18  from an engine water jacket,  32 . Coolant supply passage  42  furnishes pressurized coolant to turbocharger  14 . Coolant leaving turbocharger  14  flows through coolant return passage  46  down through utility pedestal  18  and out to the front of engine block  30 , wherein the flow is joined with coolant flow from one or more cylinder heads at a combination point  36 . Coolant return passage  46  may advantageously be configured as a cored or drilled passage within cylinder block  30 . Those skilled in the art will appreciate in view of this disclosure that combination point  36  could be configured as a water outlet or coolant surge tank or other device for combining coolant flows from more than one source, such as one or more of the engine&#39;s cylinder heads. This combination of flows offers the advantage of mitigating coolant temperature excursions which could otherwise result from the very warm coolant leaving turbocharger  14 . 
         [0034]      FIGS. 4 and 7  show a series of baffles,  35 , which are incorporated within oil return passage  34 . The serpentine path illustrated in  FIG. 7  promotes de-aeration of oil flowing from turbocharger  14  to sump  98 . 
         [0035]    The foregoing invention has been described in accordance with the relevant legal standards, thus the description is exemplary rather than limiting in nature. Variations and modifications to the disclosed embodiment may become apparent to those skilled in the art and fall within the scope of the invention. Accordingly the scope of legal protection afforded this invention can only be determined by studying the following claims.

Technology Classification (CPC): 5