Patent Publication Number: US-2011061400-A1

Title: Heat exchanger having thermoelectric element

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Korean Patent Application Number 10-2009-0088214 filed on Sep. 17, 2009, the entire contents of which application is incorporated herein for all purposes by this reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a heat exchanger having a thermoelectric element, and more particularly, to one in which a thermoelectric element unit enabling heat exchange is integrally provided with a blower. 
     2. Description of Related Art 
     In general, a vehicle is equipped with an air-conditioning system including a cooler and a heater. The air-conditioning system serves to control the temperature inside the vehicle. 
     However, the air-conditioning system does not have a function of controlling the temperature of a vehicle seat. In the summer, even if an occupant sitting on a vehicle seat lowers the temperature inside the vehicle by operating the cooler, the seat is relatively slowly cooled down. In addition, the occupant may have heat rash at the buttocks and the back, which are apt to sweat due to body heat. 
     In the winter, even if the occupant sitting on the vehicle seat raises the temperature inside the vehicle by operating the heater, the seat stays cold for a long time before the heater warms up the air. Thus, the occupant may feel chilly or cold at the buttocks or back. 
     Accordingly, these days, a seat-dedicated heating and cooling system is additionally provided, which is designed to control the temperature of the seat. An example of such a vehicle seat heating and cooling system will be illustrated with reference to  FIG. 1 . 
     The vehicle seat heating and cooling system is mounted below a vehicle seat, which includes a back and a sitting part. The heating and cooling system includes a first duct  2  communicating with the back, a second duct  4  communicating with the sitting part, and a blower  1  blowing air into the ducts  2  and  4 . Thermoelectric element housings  3  and  5  are coupled to the front ends of the ducts  2  and  4 , respectively, and thermoelectric element units (not shown) are mounted inside the thermoelectric element housings  3  and  5 , respectively. 
     The thermoelectric element housing  3  has two air outlets  3   a  and  3   b . The air outlet  3   a  serves to supply air, heated or cooled by the thermoelectric element unit, to the seat, and the air outlet  3   b  serves to exhaust air from the vehicle. The thermoelectric element housing  5  also has two air outlets  5   a  and  5   b , which function substantially the same as those of the thermoelectric element housing  3 . 
     When a thermoelectric element is used for heating air to be supplied to the seat, air is heated at one side of the thermoelectric element but is cooled at the other side of the thermoelectric element. Thus, it is required to exhaust cooled air from the vehicle. For this purpose, the thermoelectric element housing is provided with both the air outlet  3   a  or  5   a  for supplying air to the seat and the outlets  3   b  and  5   b  for exhausting air from the vehicle. In addition, the outlet  5   b  is connected to an exhaust duct  6 , which leads to the outside of the vehicle. 
     However, since the thermoelectric elements that cool or heat air are separately located on the front end of the respective duct, more thermoelectric elements are needed in the above-described vehicle seat heating and cooling system of the related art. As such, the expensive thermoelectric elements, located in multiple positions of the seat heating and cooling system, increase the price of the system while making it difficult to assemble the system. 
     In addition, a supply voltage is required in order to operate the thermoelectric elements. In the seat heating and cooling system of the related art, this complicates power supply lines for the thermoelectric elements and lowers the degree of freedom of design. 
     The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art. 
     BRIEF SUMMARY OF THE INVENTION 
     Various aspects of the present invention are directed to provide a heat exchanger having a thermoelectric element, which is integrally mounted with a blower instead of being separately mounted on a respective duct leading to a vehicle seat, whereby manufacturing costs can be reduced, the structure of the duct can be simplified, and a seat heating and cooling system can be easily assembled. 
     In an aspect of the present invention, the heat exchanger may include a housing including an intake port through which air is introduced into the housing from outside, a seat inlet supplying air to a vehicle seat, and an exhaust port through which a portion of the air introduced from outside is exhausted from the housing to outside, a blower unit mounted inside the housing and operated by a first motor to supply the air introduced into the housing through the intake port, out of the housing through the seat inlet, and a thermoelectric element disposed between the intake port and the seat inlet and heat-controlling the air introduced into the housing through the intake port. 
     The thermoelectric element may separate the intake port into an upper flow passage and a lower flow passage and wherein the blower unit is disposed in the upper flow passage and the exhaust port is formed to the lower flow passage. 
     The heat exchanger may further include first heat dissipation fins attached to an upper surface of the thermoelectric element and disposed in the upper flow passage, and second heat dissipation fins attached to a lower surface of the thermoelectric element and disposed in the lower flow passage, such that the first heat dissipation fins communicate with the intake port and the seat inlet and the second heat dissipation fins communicate with the intake port and the exhaust port. 
     The heat exchanger may further include a fan unit provided in the exhaust port, wherein the fan unit exhausts air, heat-controlled by the second heat dissipation fins of the thermoelectric element, out of the housing through the exhaust port, wherein the fan unit is driven by a rotary shaft of the first motor that drives the blower unit, and wherein the thermoelectric element has a hole through which the rotary shaft extends and is connected to the fan unit. 
     The fan unit provided in the exhaust port may be driven by a second motor. 
     The housing may include upper, middle and lower housings, wherein the upper and middle housings are coupled with each other to define a first space, inside of which the blower unit is mounted, and the seat inlet, wherein the middle and lower housings are coupled with each other to define a second space, inside of which the thermoelectric element is mounted, and the intake port, and wherein the exhaust port is formed in the lower housing under the thermoelectric element. 
     The heat exchanger may further include a first separator film disposed between the middle and lower housings to define an upper hole to form the upper flow passage and a lower hole to form the lower flow passage respectively, wherein the first separator film prevents air, introduced into the second space through the upper hole of the intake port and heat-controlled by the first heat dissipation fins of the thermoelectric element, and air, introduced into the second space through the lower hole of the intake port and heat-controlled by the second heat dissipation fins of the thermoelectric element, from mixing with each other. 
     The thermoelectric element unit includes a thermoelectric element and the first separator film extends from the thermoelectric element to form the upper and lower holes. 
     The heat exchanger may further include a second separator film to divide the second space into an upper output port and a lower output port, wherein the upper output port receives air heat-controlled by the first dissipation fins and the lower output port receives air heat-controlled by the second dissipation fins. 
     The second separator film may extend from the thermoelectric element to form the upper and lower output ports. 
     The blower unit may include a Sirocco fan, and the fan unit provided in the exhaust port comprises an axial fan, wherein the seat inlet includes at least two seat inlets and extending in the tangential direction of the circumference of the housing. 
     In another aspect of the present invention, a heat exchanger may include an upper housing, a middle housing, wherein the upper and middle housings are coupled with each other to define a first space, inside of which a blower unit is mounted, and a seat inlet, a lower housing, wherein the middle and lower housings are coupled with each other to define a second space, inside of which a thermoelectric element is mounted, and an intake port, and wherein the lower housing defines, therein, an exhaust port in which a fan is mounted, and a separator film provided between the middle and lower housings to divide the intake port into upper and lower holes, wherein the separator film prevents air, introduced into the second space and heat-controlled by the thermoelectric element, and air, introduced into the second space and heat-controlled by the thermoelectric element, from mixing with each other, whereby air introduced through the upper hole is supplied to a vehicle seat through the seat inlet after heat exchange with the thermoelectric element, and whereby air introduced through the exhaust port is exhausted to outside through the lower hole after heat exchange with the thermoelectric element. 
     In the heating and cooling system of the related art, the thermoelectric element housings are provided in the front ends of the ducts, and the thermoelectric elements are separately provided inside the housings. In contrast, according to exemplary embodiments of the invention, the heat exchanger having a thermoelectric element has an advantage of a simple structure, in which the thermoelectric element for heating and cooling air, which will be supplied to the heating and cooling system for a vehicle seat, is integrally provided with the blower. Also, in the related art, the respective ducts are separately provided in order to exhaust air, which is not supplied from the ducts to the seat, out of the vehicle. In contrast, according to various aspects of the invention, the heat exchanger having a thermoelectric element requires only one duct for exhausting air, which is not supplied to the seat. This, as a result, facilitates assembly of the system and reduces manufacturing costs. 
     Furthermore, according to various aspects of the invention, the heat exchanger can improve the degree of freedom of design inside the vehicle seat since electric lines for supplying a voltage to the thermoelectric element are simplified. 
     The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description of the Invention, which together serve to explain certain principles of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing a vehicle seat heating and cooling system of the related art. 
         FIG. 2  is a perspective view showing an exemplary heat exchanger having a thermoelectric element according to the present invention. 
         FIG. 3  is a perspective of the exemplary heat exchanger of  FIG. 2 , viewed from a different angle. 
         FIG. 4  is an exploded perspective view of the heat exchanger of  FIG. 3 . 
         FIG. 5  is a cross-sectional view taken along line A-A in  FIG. 3 . 
     
    
    
     It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. 
     In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. 
     Above all, reference should be made to the drawings, in which the same reference numerals and signs are used throughout the different drawings to designate the same or similar components. In the following description of the present invention, a detailed description of known functions and components incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. 
       FIG. 2  is a perspective view showing an exemplary embodiment of a heat exchanger having a thermoelectric element according to the present invention,  FIG. 3  is a perspective of the heat exchanger of  FIG. 2 , viewed from a different angle,  FIG. 4  is an exploded perspective view of the heat exchanger of  FIG. 3 , and  FIG. 5  is a cross-sectional view taken along line A-A in  FIG. 3 . 
     Referring to  FIGS. 2 to 5 , the heat exchanger using a thermoelectric element according to an exemplary embodiment of the present invention includes a housing  10 , a blower unit  20 , and a thermoelectric element unit  30 . The housing  10  includes intake ports  15  through which air is introduced into the housing  10  from the outside, seat inlets  16  connected to a duct that leads to a vehicle seat, and an exhaust port  17  through which a portion of air, taken in from the outside and remaining after being blown into the seat inlets  16 , is exhausted from the housing  10  to the outside. The blower unit  20  is provided inside the housing  10 , and serves to blow air, introduced into the housing  10 , out of the housing  10  through the seat inlets  16 . The thermoelectric element  30  cools and heats air introduced into the housing  10  through the intake ports  15 . 
     The housing  10  includes upper, middle, and lower housings  11 ,  12 , and  13 . The upper and middle housings  11  and  12  are coupled with each other, thereby defining a first space  50 . The middle and lower housings  12  and  13  are coupled with each other, thereby defining a second space  52 . 
     The blower unit  20  includes a motor  24  fixedly installed inside the housing  11  and blades  22  rotatably installed inside the first space  50 . The blades  22  are driven by the motor  24 . The blower unit  20  is a Sirocco fan that is a centrifugal blower having a number of blades. In the blower unit  20 , air axially enters from the bottom of the blades  22  and then radially flows over the fan blades  22 . 
     The thermoelectric element unit  30  is fixedly installed in the second space  52  defined by the middle housing  12  and the lower housing  13 . The thermoelectric element unit  30  includes a thermoelectric element  32 , which is cooled down or heated when a voltage is applied, and first and second heat dissipation fins  34  and  36  provided on both surfaces of the thermoelectric element  32 . The first and second heat dissipation fins  34  and  36  are in contact with the thermoelectric element  32 , thereby forming a heat conductive structure. 
     As described above, the thermoelectric element  32  is a Peltier element, in which one side is heated and the other side is cooled when a current is passed around the thermoelectric element  32 . The side to be heated is changed according to the direction of the current that is applied. Accordingly, in an exemplary embodiment of the present invention, when a voltage is supplied to the thermoelectric element  32 , one side of the thermoelectric element  32  to be heated and the heat dissipation fins  34  in contact with one side serve as a heater, and the other side of the thermoelectric element  32  to be cooled and the heat dissipation fins  36  in contact with the other side serve as a cooler. 
     The first and second heat dissipation fins  34  and  36  are a structure for maximizing the contact area in which air flowing through the second space  52  performs heat exchange with the thermoelectric element  32 . Although the heat dissipation fins  34  and  36  are shaped as corrugated plates, they can be modified into fin shapes. The heat dissipation fins  34  and  36  can have any shape that allows air to come into contact with the heat dissipation fins  34  and  36  while flowing in the second space  52 . 
     In this embodiment, the middle housing  12  is interposed between the blower unit  20  and the thermoelectric element unit  30 . This is to reliably partition the first space  50  from the second space  52  as well as to prevent the rotating blades  22  from interfering with the thermoelectric element unit  30 . Accordingly, the middle housing  12  is not an essential component in this embodiment. As an alternative, the middle housing  12  can be excluded. In this case, the blower unit  20  and the thermoelectric element  32  are mounted inside a space defined by coupling between the first and second housings  11  and  13 . 
     The intake ports  15  outwardly protrude from the portion of the housing  10  where the thermoelectric element unit  30  is mounted, the seat inlets  16  outwardly protrude from the portion of the housing  10  where the blower unit  20  is mounted, and the exhaust ports  17  are formed on the outer wall of the lower housing  13 , opposite the surface of the housing  10  on which the thermoelectric element unit  30  faces the blower unit  20 . 
     With this configuration, when air is introduced into the second space  52  inside the housing  10  through the intake ports  15 , it comes into contact with the thermoelectric element  30  while flowing through the second space  52 , and the blower unit  20  blows a portion of introduced air into the first space  50  so as to be exhausted from the housing  10  through the seat inlets  16 , i.e., to the duct leading to the seat. The other portion of introduced air, except for the portion of air exhausted through the seat inlets  16 , is exhausted from the housing  10  through the exhaust ports  17  of the lower housing  13 . 
     In order to maximize the efficiency of the blower unit  20 , the seat inlets  16  can be expanded in the tangential direction of the circumference of the housing  10 . When two seat inlets  16  are provided in one housing  10 , the seat inlets  16  can preferably be arranged at an angle 180° with each other. However, the angle between the seat inlets  16  is not limited to 180°, but can be set to a variety of other angles, in which the seat inlets  16  are connected to the ducts leading into the seat. 
     In addition, the configurations of the intake ports  15 , the seat inlets  16 , and the exhaust ports  17  are not limited to those shown in this embodiment, but can be modified into several other forms. For example, although the two intake ports  15  are provided in this embodiment, the number of the intake ports  15  can be changed when necessary. In addition, although the exhaust port  17  is provided in the bottom of the housing  10 , it can be provided to protrude from the side of the housing  10  like the intake ports  15  or the seat inlets  16 . 
     In addition, a separator film  14  is provided inside the housing  10 , extending from the thermoelectric element  32  along a reference line B in the center of the second space  52 . 
     In another exemplary embodiment of the present invention, another separator film  21  may be provided inside the housing  10  to divide the second space  52  into an upper output port  57  and a lower output port  58 , wherein the upper output port  57  receives air heat-controlled by the first dissipation fins  34  and the lower output port  58  receives air heat-controlled by the second dissipation fins  36 . 
     The thermoelectric element  32  is heated at one side but cooled at the other side according to its characteristics. In the case of attempting to supply cold air to the seat, it is required to supply air, cooled by the thermoelectric element  30  in the second space  52 , to the seat through the seat inlet  16 . However, if air inside the second space  52  can freely flow from the heater side to the cooler side of the thermoelectric element  30  and vice versa, cooled air can mix with heated air, thereby lowering the efficiency of the heat exchanger. 
     Thus, as shown in  FIG. 5 , the second space  52  is completed divided into first and second sections  54  and  56  by providing the separator film  14  along the reference line B, defined by the center line of the thermoelectric element  32  in the thickness direction. The separator film  14  also divides a respective intake port  15  into upper and lower holes  15   a  and  15   b . In this manner, the passage along which air, introduced through the upper hole  15   a , can flow is completely separated from the passage along which air, introduced through the lower hole  15   b , can flow. Air, introduced into the first section  54  of the second space  52  through the upper hole  15   a  of the intake port  15 , is heated or cooled by contact with the first heat dissipation fins  34  of the thermoelectric element  30 . After heat exchange with the first heat dissipation fins  34 , air is blown into the first space  50  by the blower unit  20  and is then exhausted from the housing  10  through the seat inlet  16 . In contrast, air, introduced into the second section  56  of the second space  52  through the lower hole  15   b  of the intake hole  15 , is cooled or heated by contact with the second heat dissipation fins  36  of the thermoelectric element  30 . After heat exchange with the second heat dissipation fins  36 , air is then exhausted from the housing through the exhaust port  17 . 
     As such, the separator film  14 , provided along the reference line B of the thermoelectric element  32 , prevents air heated by the thermoelectric element  30  and air cooled by the thermoelectric element  30  from mixing with each other when air is introduced into the second space  52  through the intake ports  15 . 
     In addition, the heat exchanger having a thermoelectric element in accordance with an exemplary embodiment of the invention is configured such that an axial fan  40  is installed in the exhaust port  17  of the lower housing  13 . Even if the fan  40  is not provided, air introduced into the housing  10  can be exhausted from the housing  10  through the exhaust port  17  after heat exchange with the thermoelectric element unit  30 . However, the fan  40  can more efficiently exhaust air out of the housing  10  through the exhaust port  17 , thereby improving the heat exchange efficiency of the thermoelectric element unit  30 . This especially enhances the flow rate of air, which performs heat exchange with the second heat dissipation fins  36 . When heat exchange is actively performed by the heater, the cooling efficiency of the cooler is enhanced due to the characteristics of the thermoelectric element  32 . Accordingly, it is possible to enhance the total efficiency of the heat exchanger by adding the fan  40 . 
     In addition, the fan  40 , provided in the exhaust port  17 , can be driven by a separate drive motor. It is also possible to drive the fan  40  using the motor  24  for driving the blower unit  20  in order to simplify the configuration of the system. In this case, a rotary shaft  26  extending from the motor  24  can preferably be used as a drive source for the fan  40 . The rotary shaft  26 , extending from the rotary shaft of the motor  24  of the blower unit  20 , rotates at the same speed as the rotary shaft of the motor  24  to drive the fan  40 . 
     The thermoelectric element  32  has a hole  38  through which the rotary shaft  26  can extend from the motor  24  to the fan  40 . The hole  38  is formed to penetrate through both sides of the thermoelectric element  32 , in a position corresponding to the rotary shaft  26 . The size of the hole  38  is slightly greater than the diameter of the rotary shaft  26 . 
     In the heat exchanger of this embodiment having the above described configuration, air is introduced into the heat exchanger through the upper and lower holes  15   a  and  15   b  of the intake ports  15 , driven by the blower unit  20  and the fan  40 . When air is introduced through the upper hole  15   a  of the intake port  15 , it is heated or cooled by the thermoelectric element  32  and is supplied to the seat through the first space  50  and the seat inlet  16 . In contrast, when air is introduced through the lower hole  15   b  of the intake port  15 , it is cooled or heated by the thermoelectric element  32  and is exhausted to the outside through the exhaust port  17 . 
     As an alternative, in the heat exchanger having a thermoelectric element, the structure of the fan  40  provided in the exhaust port  17  can be modified such that air is introduced into the second space  52  through the exhaust port. Except for the configuration that introduces air into the second space  52  through the exhaust port  17  by driving the fan  40 , other components are the same as those in the above-described embodiment of the invention. 
     According to this alternative embodiment, the heat exchanger introduces air into the second space  52  through the upper holes  15   a  of the intake ports  15  by driving the blower unit  20 , so that air performs heat exchange with the thermoelectric element  32  in the second space  52  and is then supplied through the seat inlet  16  to the seat. At the same time, the heat exchanger introduces air into the second space  52  through the exhaust port  17  by driving the fan  40 , so that air performs heat exchange with the thermoelectric element  32  in the second space  52  and is then exhausted to the outside through the lower holes  15   b  of the intake ports  15 . 
     For convenience in explanation and accurate definition in the appended claims, the terms “upper”, “middle” and “lower” are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures. 
     The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.