Abstract:
A heat exchanger has a plurality of tubes and a plurality of fins alternatively arranged to define a core portion of the heat exchanger. A side plate is arranged at opposite sides of the core portion. Each end of the tubes and side plates extend through a core plate. Each core plate mates with a respective tank to define a sealed chamber. The ends of the tubes are disposed within the sealed chamber. The ends of the side plates and disposed outside the sealed chamber. This allows for a non-brazed connection between the core plates and the side plates.

Description:
FIELD 
       [0001]    The present disclosure relates to heat exchangers. More particularly, the present invention relates to a heat exchanger which includes a side insert or side plate which is secured to the core plate mechanically without the use of brazing. 
       BACKGROUND 
       [0002]    The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
         [0003]    Heat exchangers are used to exchange heat between two fluids. In the automotive industry, a heat exchanger in the form of a radiator is used to exchange heat between an engine cooling fluid and air. In addition, a heat exchanger is used to exchange heat between the engine coolant fluid and air to be blown into the passenger compartment to heat the air. Also, a heat exchanger in the form of a condenser is used to exchange heat between a refrigerant and air. Finally, a heat exchanger in the form of an evaporator is used to exchange heat between a refrigerant and air that is to be blown into the passenger compartment to cool the air. 
         [0004]    Each of these heat exchangers includes a plurality of tubes through which a fluid flows, a plurality of fins arranged between adjacent tubes to be bonded to the tubes, a core plate connected to each longitudinal end of the plurality of tubes, a tank member disposed at each end of the plurality of tubes and an insert or side plate located at opposite sides of the plurality of tubes and fins. The inserts or side plates provide stability to the assembled heat exchanger. 
         [0005]    Typically, the plurality of tubes and the inserts or side plates extend through apertures formed in each core plate and this assembly is brazed to maintain its integrity as well as to seal the interface between the tubes and the core plates and interface between the inserts or side plates and the core plates. 
         [0006]    When both the insert or side plates and the plurality of tubes are brazed to the core plate, problems can occur due to thermal stress. In cold ambient temperatures and hot coolant conditions, the tubes want to expand due to their increased temperature due to the hot coolant. The inserts or side plates want to contract due to the cold ambient temperature. This creates relatively high stresses at the interfaces between the tubes and core plates and the interfaces between the inserts or side plates and the core plates. This high stress creates the potential for cracking and cooling leaks. 
       SUMMARY 
       [0007]    The present disclosure describes a heat exchanger where the tubes and core plates are brazed together. The inserts or side plates are mechanically connected to the core plates rather than being brazed or in the alternative the inserts or side plates can be lightly brazed to the core plates. The interface region between the inserts or side plates and core plate is located outside of the sealed area of the radiator tank. This structure allows the tubes to expand when necessary without being constrained by the insert or side plate. 
         [0008]    Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0009]    The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
           [0010]      FIG. 1  is a schematic view of a vehicle cooling system and a vehicle air conditioning system; 
           [0011]      FIG. 2  is a front view of the heat exchanger illustrated in the vehicle cooling system of  FIG. 1 ; 
           [0012]      FIG. 3  is an enlarged cross-sectional view of the upper portion of the heat exchanger illustrated in  FIG. 2 ; 
           [0013]      FIG. 4  is a top view of one end of the heat exchanger illustrated in  FIG. 2 ; and 
           [0014]      FIG. 5  is a partial bottom view of the header tank illustrated in  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. There is illustrated in  FIG. 1 , a typical cooling and heating system for an automobile. A water cooled engine  10  is cooled by water flowing through a water circuit  12 . Hot water from engine  10  is sent to a radiator or heat exchanger  14 . A fan  16  draws air through radiator or heat exchanger  14  for cooling purposes. The water leaving heat exchanger or radiator  14  is routed back to engine  10  by water circuit  12 . Hot water from engine  10  is also sent to a heat exchanger  18  which is located within an air conditioning case  20  for heating a passenger compartment of the vehicle. The water returned from heat exchanger  18  is routed back to engine  10  by water circuit  12 . A pump  22  controls the flow of water within water circuit  12 . 
         [0016]    An air conditioning system includes a compressor  30  which compresses refrigerant flowing through a refrigerant circuit  32 . Compressed refrigerant from compressor  30  is sent to a condenser or heat exchanger  34  which also receives air drawn by fan  16 . Refrigerant from condenser or heat exchanger  34  passes through an expansion valve  36  and then to an evaporator or heat exchanger  38  through refrigerant circuit  32 . Evaporator or heat exchanger  38  is also disposed within casing  20  and it is used to cool the passenger compartment of the vehicle. The refrigerant leaving evaporator or heat exchanger  38  flows through refrigerant circuit  32  and is sent to a gas/liquid separator  40  and from gas/liquid separator  40 , the refrigerant in gas form is drawn into compressor  30 . 
         [0017]    Air-conditioning case  20  defines an air passage  42  through which air flows into the passenger compartment. An inside air inlet  44  for introducing air from inside the passenger compartment and an outside air inlet  46  for introducing air from outside the passenger compartment are provided at an upstream end of case  20 . An inside/outside air switching door  48  is located to open and close inlets  44  and  46 . A centrifugal blower  50  draws air in through inlets  44  and  46  and blows this air through evaporator  38 , and heat exchanger  18  located within air passage  42  and then into the passenger compartment. An air mixing door  52  adjusts the temperature of the air to be blown into the passenger compartment. 
         [0018]    A face opening  54  blows air toward the upper portion of a passenger. A foot opening  56  blows air toward a lower portion of a passenger. A defroster opening  58  blows air toward a windshield of the vehicle for defrosting and defogging of the windshield. 
         [0019]    Referring now to  FIGS. 2-5 , heat exchanger or radiator  14  is illustrated in greater detail. While the present disclosure is being described using heat exchanger or radiator  14 , it is within the scope of the present invention to have heat exchanger  18 , condenser or heat exchanger  34  and evaporator or heat exchanger  38  incorporate the features of the present disclosure. 
         [0020]    Heat exchanger or radiator  14  comprises a core portion  60 , a first tank member  62  and a second tank member  64 . Core portion  60  comprises a plurality of tubes  66 , a plurality of fins  68 , a pair of inserts or side plates  70  and a pair of core plates  72 . 
         [0021]    Each of the plurality of fins  68  is a corrugated fin formed into a wave shape by bending a thin plate. The plurality of tubes  66  and the plurality of fins  68  are alternately stacked with each other. Inserts or side plates  70  are attached to the outermost fin on each side of core portion  60  to reinforce core portion  60 . Inserts or side plates  70  extend in the same longitudinal direction as the plurality of tubes  66 . 
         [0022]    Each core plate  72  is provided with a plurality of tube holes  74  within which an end portion of the plurality of tubes are inserted. Each core plate  72  also includes a pair of insert or side plate holes  76  within which a respective insert or side plate  70  is inserted. Each core plate  72  also defines a generally rectangular sealing surface  80  which extend along the two longitudinal edges of core plate  72  and extends between the outermost tube holes  74  and the insert or side plate holes  76 . In addition, each core plate  72  has a tank insertion portion  82  at its outer peripheral portion within which an outer peripheral portion  84  of first and second tank members  62  and  64  are inserted so that a tank space  86  communicating with the plurality of tubes  66  is formed. A seal  88  interfaces between sealing surface  80  of core plate  72  and outer peripheral portions  84  of tank members  62  and  64  to seal tank space  86  from the outside environment. Furthermore, a plurality of claw portions  90  are located along the outer periphery of each core plate  72 . Claw portions  90  are crimped over to maintain the attachment of tank members  62  and  64  to their respective core plate  72 . 
         [0023]    First and second tank member  62  and  64  are preferably made of a resin material such as a nylon material including glass fiber to have heat resistance and strength sufficient for the application. While tank members  62  and  64  are described as being made of a resin, other materials for tank members  62  and  64  can be utilized. Each tank member  62  and  64  is formed into an approximate U-shape in cross section. The open end of the U-shape faces its respective core plate  72 . A plurality of ribs  92  are spaced along the smaller end wall of each tank member  62  and  64  to provide additional stiffness to tank members  62  and  64  and thus preventing any warping. 
         [0024]    An inlet pipe  94  and an outlet pipe  96  are provided in tank members  62  and  64  to allow for the inflow and outflow of coolant. Additionally, a cooling filling port  98  is provided in tank member  62  for maintaining the supply of coolant in the system. 
         [0025]    Referring to  FIG. 3 , the insert or side plate holes  76  are located at a position outside of the tank space  86 . An insert or side plate pocket  110  is defined by each side of each header tank  62  and  64 . Each end of each insert or side plate  70  extend through a respective insert or side plate hole  76 . The end of insert or side plate  70  can be inserted through the respective insert or side plate hole  76  without any retention device, or a retention device such as a light brazing can be utilized to secure the connection. Each insert of side plate  70  is brazed to the adjacent fin  68  so movement of insert or side plate  70  with respect to the remainder of core portion  60  is prohibited. 
         [0026]    The separation of the connection of each insert or side plate  70  and the connection of each tube  66  with core plates  72  eliminates the thermal stress and the associated problems in cold ambient temperatures with hot fluid running through tubes  66 .