Abstract:
A gas cooler for an internal combustion engine is provided that includes a gas channel for permeating with a gas flow fed to the internal combustion engine in a flow direction, and a heat exchanger inserted in the gas channel in an insertion direction, wherein the heat exchanger comprises at least one connection for feeding or discharging a fluid for cooling the gas flow, wherein the connection comprises a first connection part connected to the heat exchanger before inserting the hat exchanger into the gas channel, and a second connection part that can be connected to the first connection part from the outside.

Description:
[0001]    This nonprovisional application is a continuation of International Application No. PCT/EP2010/061340, which was filed on Aug. 4, 2010, and which claims priority to German Patent Application No. DE 10 2009 039 569.5, which was filed in Germany on Sep. 1, 2009, and which are both herein incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a gas cooler for an internal combustion engine. 
         [0004]    2. Description of the Background Art 
         [0005]    It is known to provide charge air coolers for indirect cooling of a gas flow in an internal combustion engine in which a heat exchanger is inserted into a housing which is permeated by the charge air. Fixed connections for connecting a cooling fluid line are provided on the heat exchanger. Due to the fixed design of the connecting pieces, the configuration thereof relative to the housing and to the direction of insertion is subject to limitations. 
       SUMMARY OF THE INVENTION 
       [0006]    It is therefore an object of the invention to provide a gas cooler for an internal combustion engine which has a particularly flexible means of installation. 
         [0007]    Due to the design of a connection, which has a first connecting part connected to the heat exchanger and a second connecting part which is connectable to the first connecting part from the outside, the heat exchanger may, for example, be first inserted into the gas channel or a housing, after which the second connecting part is attached to the first connecting part by engaging with an opening in the gas channel. This permits a versatile positioning of the connections on the heat exchanger in a given design of the gas channel. In addition, the heat exchanger may be designed with a view toward a modular system in which the connections may be provided in different positions of the gas channel, depending on the requirements. 
         [0008]    A gas channel in the sense of the invention can be a channel for supplying a combustion gas to the internal combustion engine. The combustion gas may be pure charge air, an air/exhaust gas mixture or a recirculated exhaust gas. A gas channel is also understood to be, in particular, an intake manifold module which includes a supplying channel as well as a distribution of combustion air to the cylinders of the internal combustion engine, if necessary including connections on the cylinder head of the internal combustion engine. 
         [0009]    In an embodiment, the heat exchanger is at least partially attached to the gas channel by connecting the two connecting parts. This simultaneously makes it possible to at least partially, possibly even completely, eliminate additional attachment means such as screws, clamps or adhesives. 
         [0010]    In an embodiment, the first connecting part may be screwed to the second connecting part. The second connecting part particularly preferably has an outer thread which may be screwed into an inner thread of the first connecting part. This enables the heat exchanger to be designed without projecting parts, and it may be inserted into the gas channel in a particularly space-saving and versatile manner. The design of the connection of the connecting parts using a screw connection also has the essential advantage that only a small leakage flow of the fluid into the gas channel may occur even in the event of defects such as the failure of a seal, and the danger of a water hammer destroying the internal combustion engine is thus largely avoided, due to the method for connecting the screw connection of the connecting parts. Alternatively, it is also possible for the second connecting part to have an inner thread which may be screwed into an outer thread of the first connecting part. 
         [0011]    In an embodiment, a sealing member, in particular in the form of an O ring seal, can be provided on at least one of the two connecting parts. A sealing member is particularly preferably provided on each of the two connecting parts. The sealing member makes it possible to seal the fluid against the gas channel, on the one hand, and to seal the gas channel against the outer area, on the other hand. If two sealing members are provided, a particularly secure sealing of the fluid against the outer area may also be established. 
         [0012]    The connecting parts can each have a radial collar, a housing wall of the gas channel being accommodated between the collars at least by means of a friction fit. This permits a good seal, on the one hand, and a secure hold of the heat exchanger on the gas channel, on the other hand, to be easily achieved. A sufficient extension of the collar also causes the acting forces to be distributed onto a larger area of the housing wall, so that even a heavy heat exchanger may be securely held on a comparatively weakly dimensioned gas channel wall, which may be made, for example, of plastic. A particularly preferred dimensioning of the connecting parts in this sense is achieved if the collars have at least an outer diameter that is at least approximately twice the size of an inner diameter of the fluid-conducting passage of the connecting parts. 
         [0013]    The first connecting part can be integrally connected to the heat exchanger, in particular by means of soldering or welding. A simple, fluid-tight and mechanically loadable connection of the first connecting part to the heat exchanger is provided in this manner. In particular, the first connecting part and the rest of the heat exchanger may be designed as a common block which is soldered in a soldering furnace. 
         [0014]    The second connecting part can have a projection for connecting a fluid line, which is particularly preferably designed as a bead or a quick-action coupling. If a bead projection is used, a hose may be placed over the second connecting part and secured with the aid of a hose clamp, for example. However, the connecting part may also be a fast-action coupling of any known design. The features according to the invention have a particularly advantageous effect in specific embodiments in which an insertion direction of the heat exchanger and a direction of conducting the fluid into the connection do not run parallel to each other. 
         [0015]    In an embodiment, the heat exchanger may be attached to a cover of the gas channel with the aid of the connecting parts, the cover being attachable to the gas channel together with the heat exchanger. In this manner, a simple and reliable, fluid-tight assembly on the cover may be carried out, after which the cover may be inserted into the gas channel together with the heat exchanger attached thereto under frequently unfavorable assembly conditions in the engine compartment. A configuration and assembly sequence of this type are advantageous, in particular, for maintenance purposes. 
         [0016]    Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein: 
           [0018]      FIG. 1  shows a spatial overall view of a gas cooler according to the invention according to a first exemplary embodiment; 
           [0019]      FIG. 2  shows a partial sectional view of the gas cooler from  FIG. 1  in the area of a fluid connection; 
           [0020]      FIG. 3  shows two spatial representations of a connection of the gas cooler from  FIG. 1 ; 
           [0021]      FIG. 4  shows two spatial views of a first connecting part of the connection from  FIG. 3 ; 
           [0022]      FIG. 5  shows two spatial views of a second connecting part of the connection from  FIG. 3 ; 
           [0023]      FIG. 6  shows a spatial view of the gas cooler from  FIG. 1  after assembly; 
           [0024]      FIG. 7  shows a spatial representation of a second exemplary embodiment of the invention after assembly. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    The gas cooler according to the invention illustrated in  FIG. 1  according to a first exemplary embodiment comprises a gas channel  1 , which is designed as a housing made of plastic for conducting a combustion gas for an internal combustion engine along a flow direction S. A heat exchanger  2 , which is designed by a stack of flat tubes  3  which may be permeated by a fluid coolant as the cooling fluid and which has intermediate ribs (not illustrated) is disposed in gas channel  1 . 
         [0026]    Collector boxes  4 , which are used to distribute the coolant to flat tubes ( 3 ), are disposed on the ends of the flat tubes (see  FIG. 6 , in particular). One connection  5  is provided for each of collector boxes  4  for feeding and discharging the coolant. In the present case, connections  5  are each located on side end plates of the collector boxes, so that the flow direction of the fluid into the connections runs perpendicularly to the extension direction of flat tubes  3 . 
         [0027]    Each of the two connections  5  has the same structural design and comprises a first connecting part  6  and a second connecting part  7 . First connecting part  6  is designed as a rotationally symmetrical component which has a hollow cylindrical neck piece  6   a  and a collar  6   b  which projects radially from neck piece  6   a.  A groove-like, annular indentation  6   c  for inserting a first sealing member in the form of an O ring seal  8  are located in collar  6   b.    
         [0028]    Second connecting part  7  is also designed as a largely rotationally symmetrical body which comprises a hollow cylindrical screw connecting piece  7   a  having an outer thread provided thereupon and a collar  7   b  projecting radially from screw connecting piece  7   a.    
         [0029]    A projection for connecting a fluid line which is designed as a hollow cylindrical section  7   c  having a bead  7   d  is provided on the side of collar  7   b  opposite screw connecting piece  7   a.  A hose for fluid feeding or discharge may be pushed over section  7   c  having bead  7   d  and secured with the aid of a hose clamp. 
         [0030]    An annular recess  7   e  adjoining screw connecting piece  7   a  is also provided in collar  7   b  on the side of the screw connecting piece for inserting a second  0  ring seal  9 . 
         [0031]    The two connecting pieces  7 ,  8  may each be designed as metal molded parts, for example by deep-drawing them from a metal disk. A brazing may be provided at least on the side of the collar on the neck piece side, in particular in the case of first connecting piece  6 . First connecting piece  6  is inserted into a corresponding opening in collector box  4  of heat exchanger  2  and soldered over a wide area with the aid of neck piece  6   a.  In particular, first connecting piece  6  is soldered to form a block in a soldering furnace together with collector boxes  4  formed from brazed sheets and the flat tubes and ribs inserted into passages in the bottom of collector boxes  4 . 
         [0032]    An inner thread, into which hollow-cylindrical screw connecting piece  7   a  of second connecting piece  7  may be screwed by means of its outer thread, is provided in neck piece  6   a  of first connecting part  6 . 
         [0033]    As shown in the sectional drawing in  FIG. 2 , in particular in connection with the exploded view of the gas cooler according to  FIG. 6 , the gas cooler is assembled as follows: First O ring seal  8  is inserted into groove  6   c  of first connecting part  6 , after which a cover  1   a  of gas channel  1 , in which two openings are provided for connections  5 , is placed on heat exchanger  2  or the first connecting parts. 
         [0034]    The second connecting parts, into which second ring seals  9  were previously inserted into indentations  7   e,  are then screwed into first connecting parts  6 , hollow cylindrical screw connecting pieces  7   a  engaging with the openings in cover  1   a.  As illustrated in the sectional view in  FIG. 2 , cover  1   a  is thus clamped by means of a friction fit between collars  6   b,    7   b  of connecting parts  6 ,  7 , ring seals  8 ,  9  guaranteeing a sealing of the fluid against the inner chamber of gas channel  1  and against the outer area and simultaneously guaranteeing a sealing on the gas side between the inner chamber and the outer area. 
         [0035]    According to the true-to-scale drawing in  FIG. 2 , collars  6   b,    7   b  project radially over the edges of the opening in cover  1   a  to the extent that a particularly stable clamping hold is ensured over a wide area by means of a friction fit. 
         [0036]    According to the insertion direction indicated in  FIG. 6 , heat exchanger  2 , together with cover part  1   a  attached thereto, is inserted into gas channel  1  perpendicularly to the flow direction of gas S, cover  1   a  coming to rest on the edge of gas channel  1  and being attached gas-tight with the aid of a screw connection, adhesion or other suitable measures. 
         [0037]      FIG. 7  shows a further specific embodiment of the invention in which connections  5  are oriented perpendicularly to the insertion direction of heat exchanger  2  with regard to the fluid flow. The horizontal arrow, which illustrates the screw-in direction of second connecting parts  7 , also corresponds to the flow direction of the fluid in connection  5  and is perpendicular to the insertion direction of heat exchanger  2  into gas channel  1  indicated by the perpendicular part. In this specific embodiment, heat exchanger  2  is first inserted into gas channel  1  until first connecting parts  6  overlap with openings  10  in the wall of gas channel  1 . To complete connections  5 , second connecting parts  7  are then inserted into openings  10  and screwed into first connecting parts  6 . Both a sealing of connecting parts  6 ,  7  and a mechanical holding of heat exchanger  2  on gas channel  1  are achieved with the aid of collars  6   b,    7   b  as well as ring seals  8 ,  9 . 
         [0038]    Cover  1   a  is subsequently placed onto gas channel  1  and attached to form a seal. 
         [0039]    It is understood that, in addition to ring seals  8 ,  9 , other sealing measures may be provided, for example an adhesion or the use of a liquid thread sealant. Such further measures preferably do not prevent the screw connections of connecting parts  6 ,  7  from being detached, which makes it possible to maintain or replace heat exchanger  2  disposed in gas channel  1 . 
         [0040]    The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.