Patent Publication Number: US-2006016092-A1

Title: Washing machine or drying machine having drying duct with heater

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
      This application claims the benefit of Korean Patent Application No. 2004-0056274, filed Jul. 20, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      An apparatus consistent with the present invention relates to a washing machine and, more particularly, to a washing machine supplying air at a high temperature, which is heated by a heater provided inside a drying duct, into a drum to dry clothes.  
      2. Description of the Related Art  
      Generally, a washing machine is an appliance intended to carry out a washing operation by falling clothes during rotation through 360 degrees of a rotatable washing chamber, and it also carries out rinsing, dewatering and drying operations.  
      A drying operation of the washing machine is classified into a circulation drying operation circulating inner air discharged from a drum, and a non-circulation drying operation supplying external air into the drum to dry the clothes.  
      A conventional washing machine comprises a drum accommodating clothes; a drying duct provided to be communicated with the drum; a fan introducing air into the drying duct; and a heater provided inside the drying duct and heating the air from the fan. With this configuration, the air which is heated by the heater to a high temperature is supplied into the drum to dry the clothes. The conventional washing machine with this configuration is disclosed in Korean Patent Application Nos. 10-2002-0001733 and 10-2002-0052977.  
      As shown in  FIG. 1 , the drying duct  2  comprises aluminum material with good heat-resistance to protect a surface thereof from the heater  4  generating heat at a high temperature.  
      However, the heat generated from the heater  4  is likely to radiate from the drying duct  2 , thereby causing heat-loss. Accordingly, heating efficiency of the drum washing machine is relatively decreased and power consumption thereof is increased.  
      Also, due to the quality of the material of the drying duct  2 , the surface temperature of the drying duct  2  is increased so that the drum washing machine may separately control the temperature thereof and the drying duct  2  may be designed to minimize heat-transformation by the heater  4  by using heat-resisting material.  
     SUMMARY OF THE INVENTION  
      Illustrative, non-limiting embodiments of the present invention overcome the above disadvantages and other disadvantages not described above. Also, the present invention is not required to overcome the disadvantages described above, and an illustrative, non-limiting embodiment of the present invention may not overcome any of the problems described above.  
      Accordingly, an aspect of the present invention provides a washing machine which prevents heat generated by a heater from being radiated from a drying duct, thereby reducing heat-loss.  
      Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention.  
      The foregoing and/or other aspects of the present invention are achieved by providing a washing machine comprising: a drum; a drying duct communicating with the drum; a fan which introduces air into the drying duct; and a heater provided in the drying duct and which heats the air from the fan, wherein the drying duct is insulated so as to prevent heat generated by the heater from being radiated outward.  
      According to an exemplary embodiment of the present invention, the drying duct comprises an outer duct; an inner duct provided inside the outer duct, and on which the heater is disposed; and a heat insulating part provided between the outer duct and the inner duct.  
      According to an exemplary embodiment of the present invention, the heat insulating part comprises an air layer provided between the outer duct and the inner duct.  
      According to another exemplary embodiment of the present invention, the heat insulating part comprises an insulator provided between the outer duct and the inner duct.  
      According to a further exemplary embodiment of the present invention, the inner duct comprises aluminum.  
      According to a still further exemplary embodiment of the present invention, the outer duct comprises plastics.  
      The present invention further provides a drying machine comprising a drum; a drying duct communicating with the drum; a fan which introduces air into the drying duct; and a heater provided in the drying duct and which heats the air from the fan, the drying duct being insulated so as to prevent heat generated by the heater from being radiated outward. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings, in which:  
       FIG. 1  is a sectional view illustrating a configuration of a drying duct of a conventional drum washing machine;  
       FIG. 2  is a perspective view of a washing machine according to the present invention;  
       FIG. 3  is a sectional view of a washing machine according to the present invention;  
       FIG. 4  is a sectional view illustrating a first embodiment of a drying duct provided in a washing machine according to the present invention; and  
       FIG. 5  is a sectional view illustrating a second embodiment of a drying duct provided in a washing machine according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE ILLUSTRATIVE, NON-LIMITING EMBODIMENTS OF THE INVENTION  
      Reference will now be made in detail to the illustrative, non-limiting embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.  
      As shown in  FIGS. 2 and 3 , a washing machine consistent with the present invention comprises a main body  10  of a hexahedron shape; a cylindrical drum  20  provided in the main body  10 , and for containing clothes therein; a cylindrical washing chamber  22  rotatably provided in the drum  20 , and having a dewatering hole formed on a wall thereof; a driving motor  23  provided in a lower portion of the drum  20 , and rotating the washing chamber  22  clockwise or counterclockwise to operate a washing, rinsing and dewatering process; and a door  24  provided to be opened/closed in a front portion of the main body  10 .  
      In an upper portion of the drum  20  is respectively provided a water supply unit such as a water supply valve  25 , a water supply pipe  26 , a detergent dissolving unit  27  and the like to supply water and at the same time dissolve a laundry detergent, and a drying unit to dry the clothes after the dewatering process.  
      The drying unit comprises a fan  70  provided in an upper portion of the drum  20 ; a drying duct  80  provided to be communicated with the fan  70  and an air inlet  21  a of the drum  20 ; a heater  60  provided inside the drying duct  80 ; a condensing duct  30  communicating with an air outlet  21   b  of the drum  20  and the fan  70 ; a coolant spray  40  provided inside the condensing duct  30 , and for spraying coolant; and a coolant supply pipe  42  connected to the coolant spray  40  and supplying the coolant to the coolant spray  40 .  
      With this configuration, air supplied by the fan  70  passes through the drying duct  80  and is heated by the heater  60 . The heated air is supplied into the drum  20  through the air inlet  21   b  to dry the clothes. The air of high temperature and high humidity, which is generated during the drying process, is introduced into the condensing duct  30  through the air outlet  21   b  of the drum  20 , and then moisture in the air at high temperature and high humidity, which was introduced into the condensing duct  30 , is discharged outward after the moisture is condensed by the coolant sprayed through the coolant spray  40  when the air of high temperature and high humidity is introduced into the drying duct  80  through the condensing duct  30 .  
      Inside the condensing duct  30  is provided a condensing guide  50  to enhance condensation efficiency. The shape and an installation position of the condensing guide  50  may be variously changed as necessary.  
      In a lower portion of the drum  20  is provided a drain unit comprising such as, for example, a drain pipe  28 , a drain pump  29  and the like to drain washing water inside the drum  20 .  
      As shown in  FIGS. 4 and 5 , the drying duct  80  comprises an outer duct  82 ; an inner duct  84  provided inside the outer duct  82  and accommodating the heater  60 ; and a heat insulating part  86  provided between the outer duct  82  and the inner duct  84 . The drying duct  80  is insulated to reduce heat-loss of the heat generated from the heater  60  and to minimize an increase of surface temperature by the heater  60 .  
      The outer duct  82  and the inner duct  84  may be respectively divided into an upper part and a lower part so as to be easily assembled and accommodate the heater  60 . However, the configuration thereof may comprise a single body and may be variously changed as necessary.  
      The heat insulating part  86  may prevent the heat-loss of the heat generated by the heater  60  and may minimize the increase of the surface temperature of the outer duct  82 . The heat insulating part  86  is preferred, but not necessary, to entirely cover an inside of the outer duct  82 . However, the heat insulating part  86  may partly cover the inside thereof.  
      The heat insulating part  86  may comprise an air layer in a space between the outer duct  82  and the inner duct  84  as shown in  FIG. 4  or comprise an insulator between the outer duct  82  and the inner duct  84  as shown in  FIG. 5 . Specially, when the heat insulating part  86  comprises the air layer, the air layer is preferably, but not necessarily, trapped in an airtight space so as not to allow air to flow in or out of the airtight space.  
      The insulator may selectively comprise materials with good heat-insulation.  
      The inner duct  84  may comprise aluminum with heat resistance or stainless steel, etc. which may reflect the heat generated from the heater  60  to an inside thereof to enhance heating efficiency. The inner duct  84  may comprise various materials so far as the inner duct  84  is not transformed by the heat from the heater  60 .  
      Because the heat insulating part  86  insulates the outer duct  82  from the heat, the surface temperature of the outer duct  82  is not increased so that the outer duct  82  may selectively comprise aluminum or plastics, etc.  
      The present invention is described with regard to the washing machine of circulating drying operation by way of an exemplary embodiment. However, all kinds of washing machines or drying machines comprising the drying duct having the heater, and of a non-circulating operation may be provided therein.  
      Moreover, while the present invention describes a circulation drying operation washing machine as an exemplary embodiment, it is possible that similar devices such as a non-circulation drying operation washing machine and a drying machine comprising a condensing duct to have a built-in heater are also usefully applied by those skilled in the art. In such a case, a drum of a washing machine performs the same function as a drum of a drying machine to accommodate clothing. Also, the other elements are identically applicable.  
      The configuration of the drying machine is similar to that of the washing machine shown in  FIGS. 2 and 3 . Thus, the drawing of the drying machine is not shown in this specification.  
      Although exemplary embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.