Abstract:
A charge air conditioning system, including a charge air booster, a refrigerant-to-air intercooler which is integral with the charge air booster, and a refrigeration system for supplying refrigerant to the refrigerant-to-air intercooler.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a system in which charge air for an automotive engine is compressed and cooled by the same rotating machine.  
           [0003]    2. Disclosure Information  
           [0004]    Automotive history is replete with designs for charge boosting of reciprocating combustion engines. A veritable plethora of systems have been used, including turbochargers, superchargers, and other such devices. A common problem associated with turbocharging and supercharging is the necessity of removing heat from the compressed air charge. Heat should be reduced from the charge for a couple of reasons, such as increasing density of the air charge, and helping to prevent knock. Unfortunately, the need for charge air heat extraction, which is commonly called intercooling, greatly increases the complexity of the charge air system because the charge air flowing from the turbocharger, supercharger or other device, must pass through a heat exchanger, which of course must be supplied not only with the charge air but also with a cooling fluid, whether it be ambient air or some other fluid. Accordingly, it has not generally been possible to close couple superchargers to engines very readily in any package efficient manner, given the necessity or at least the desirability, to use charge air intercooling.  
           [0005]    A system according to the present invention solves the problems associated with prior boosting and charge air cooling systems by combining these functions into a single rotating machine. As will be explained in further detail below, the charge compression machine may comprise either a turbocharger or a supercharger, but in any event, the present machine uses refrigeration actually incorporated within the compression machine or booster to accomplish charge air cooling, thereby producing a very lightweight, compact, energy efficient, and powerful engine assist device.  
         SUMMARY OF THE INVENTION  
         [0006]    An engine having a charge air conditioning system comprising a charge air booster, a refrigerant-to-air heat exchanger integral with the charge air booster, and a refrigeration system for supplying refrigerant to the refrigerant-to-air heat exchanger.  
           [0007]    A charge air booster according to the present invention may comprise a supercharger driven by the engine directly and mechanically, or a turbocharger driven by exhaust gas from the engine, or a supercharger driven indirectly by an electric motor or hydraulically. In any event the refrigerant is preferably furnished to the heat exchanger as a liquid. The liquid may comprise either a liquid which does not change state in its course through the refrigerant-to-air heat exchanger, or a more traditional refrigerant which does change state from a liquid to a gas on its course through the refrigerant-to-air heat exchanger. In the latter case, the heat exchanger may comprise an evaporator which is mounted within the charge air booster, and with the refrigeration system providing liquid refrigerant to the evaporator, so that at least some of the refrigerant changes to a gas while the refrigerant is flowing through the evaporator so as to extract heat from air flowing through the charge booster. In the event that the booster comprises a centrifugal compressor, the evaporator may be mounted within a cover section of the compressor. As such, the evaporator may comprise an annular flow passage having an inlet for liquid refrigerant, an outlet for vaporized refrigerant, and an inner wall comprising a portion of the cover of the compressor. In the event that a liquid is used for the refrigerant, the annular flow passage feature may be retained. The flow passage will incorporate an inlet and outlet for liquid.  
           [0008]    If a refrigeration system using a change of phase refrigerant is used as part of the current system, the refrigeration system may be used to provide refrigerant not only to the intercooler but also to an evaporator comprising a portion of a passenger cabin climate control system. In this case, the refrigerant system will of course be powered by the engine of the vehicle.  
           [0009]    A charge air conditioning system with intercooling according to the present invention may be applied to a V-type engine. The supercharger and inner cooler may thus have outlets for providing chilled and compressed air to both banks of a V-type engine.  
           [0010]    A method of providing compressed and thermally densified air charge to an engine includes the steps of filtering an air stream flowing into an engine, measuring the mass of air flowing into the engine, simultaneously compressing and extracting heat from the air charge, and conducting the compressed and thermally densified air to the engine.  
           [0011]    It is an advantage of the present invention that air may both be compressed and chilled in a single machine taking up less space, weighing less and using less energy than prior art systems for compressing and intercooling charge air furnished to an engine.  
           [0012]    It is a further advantage of the present invention that the present system will reduce costs associated with charge air compressing and intercooling.  
           [0013]    Other advantages, as well as objects of the present invention will become apparent to the reader of this specification. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a schematic representation of an engine having a charge air boosting and intercooling system according to the present invention.  
         [0015]    [0015]FIG. 2 is a partially schematic representation of a charge air boosting and intercooling device according to one aspect of the present invention.  
         [0016]    [0016]FIG. 3 is an example of a mechanically driven device according to the present invention taken along the line A-A of FIG. 2.  
         [0017]    [0017]FIG. 4 is an example of a turbocharger device according to the present invention taken along the line A-A of FIG. 2. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]    As shown in FIG. 1, booster  10  is applied to engine  12 . The engine receives air from air filter  14  which flows through airflow sensor  16  into booster device  10 . Air is compressed and then chilled or intercooled within booster device  10  before it flows through discharge pipe  34  and into plenum  18  and then through air distribution pipes  20  into engine  12 . The flow of the air into the engine is partially controlled by throttle  22 . Booster  10  has the capability of not only compressing, but also intercooling air furnished to engine  12  because booster  10  is furnished with refrigerant which flows through a control device  58  having gone through and being condensed by condenser  26  following compression by compressor  24 . Control device  30  controls the flow to air conditioning evaporator core  32 , which is used to provide cooling for the cabin air of the automotive vehicle.  
         [0019]    As noted above, a system for providing refrigerant to booster  10  could also comprise a circulating liquid with condenser  26  being replaced with a tank which merely contains a liquid cooled by ambient air or other means. Such details are left to those skilled in the art and wishing to apply a system according to the present invention.  
         [0020]    [0020]FIG. 2 illustrates a charge air booster and intercooling device according to the present invention in which air entering inlet  38  is picked up by impeller  36  and compressed and sent to outlet  40  into discharge pipe  34 . According to the present invention, while the air is being compressed, it is simultaneously chilled because refrigerant circulates into inlet  44  in through a plurality of passages or channels in the outer wall of cover  41  and having circulated through channels  42 , leaves the unit at outlet  46 .  
         [0021]    [0021]FIG. 3 illustrates greater detail of channels  42  and  43 . It is noted that channels  42  are formed in cover section  41 , whereas channels  43  are formed in cap plate  39 . Those skilled in the art will appreciate in view of this disclosure that other types of refrigerant conducting channels and internal fin arrangements may be used with a charge air cooler and compressor according to the present invention.  
         [0022]    The device of FIG. 3 has a pulley  48  to illustrate a belt drive from the engine&#39;s crankshaft or other rotating shaft of engine  12 . Those skilled in the art will appreciate in view of this disclosure, however, that other types of drives, such as gear drive or chain drive, hydraulic drive, electric motor drive, or other types of drives could be used with the device of FIG. 3.  
         [0023]    [0023]FIG. 4 illustrates a device in which impeller  36  is driven by a turbo device  52  having a turbine according to conventional usage, with the turbine having exhaust inlet  54  and outlet  56 . The illustrated refrigerant channels  42  and  43  are similar to those illustrated in FIG. 3.  
         [0024]    While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.