Patent Publication Number: US-8109120-B2

Title: Steam generating device and washing machine having the same

Description:
This application claims the benefit of Korean Patent Application No. 10-2006-0058061, filed on Jun. 27, 2006, which is hereby incorporated by reference as if fully set forth herein. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a washing machine, and more particularly to a steam generating device, which generates steam to be supplied to a washing machine, and a washing machine having the steam generating device. 
     2. Discussion of the Related Art 
     Generally, washing machines are classified into a pulsator type, in which a washing operation is carried out using a flow of water generated in accordance with the rotation of a pulsator, and a drum type, in which a washing operation is carried out using the heads of wash water and laundry falling down in a horizontally-installed drum and frictional force generated between the drum and the laundry during rotation of the drum. 
     Recently, a washing machine, which has a function capable of washing laundry using steam, has been proposed. When steam is used in a washing operation, as in such a washing machine, it is possible to reduce the consumption of water and electricity, to achieve an enhancement in washing performance, to remove creases and odor, and to prevent generation of static electricity. 
     A drum washing machine, which performs a washing operation, etc., using steam, will be described hereinafter with reference to  FIG. 1 . 
     The drum washing machine includes a cabinet  10  forming an appearance of the washing machine, a cylindrical tub  20  horizontally supported by the cabinet  10  in the interior of the cabinet  10 , to store wash water, a drum  30  rotatably installed in the tub  20 , and a drive motor (not shown) for driving the drum  30 . An inlet  13  is formed at a front side of the cabinet  10 . The inlet  13  communicates with the interior of the drum  30  so that laundry can be put into or taken out of the drum  30  through the inlet  13 . A door  11  is mounted to the inlet  13 , to open or close the inlet  13 . Water supply valves  15  are provided at one side of the drum washing machine. The water supply valves  15  are connected to external water pipes (not shown), respectively, so as to supply water to the tub  20 . The water valves  15  are connected to a detergent box  27  via a hot water pipe  25   a  and a cold water pipe  26 , respectively. 
     The drum washing machine also includes a steam generating device  50  for supplying steam to the drum  30 . A water supply hose  25  and a steam hose  53  are connected to the steam generating device  50 . The water supply hose  25  supplies water to the steam generating device  50 , whereas the steam hose  53  supplies steam generated from the steam generating device  50  to the drum  30 . Typically, the water supply hose  25  is connected to a hot water side of the water supply valve  15 . The steam hose  53  has an end preferably having a nozzle shape, so as to effectively spray steam into the drum  30 . Preferably, the steam hose  53  is installed such that the nozzle-shaped end thereof, from which steam is discharged, is exposed to the interior of the tub  20 . 
     The configuration of the steam generating device  50  will be described in more detail with reference to  FIGS. 2 and 3 . 
     The steam generating device  50  includes a case  80 . The case  80  includes a lower housing  81  forming an appearance of the steam generating device  50  and an upper housing  82  coupled to an upper end of the lower housing  81 . A space for storing water is defined in the lower housing  81 . The steam generating device  50  also includes a heater  55  for heating water stored in the case  80 . 
     A water supply port  52   b  is formed at one side of the housing  82 . The water supply port  52   b  is connected to the water supply hose  25 , to introduce water from the water support hose  25  into the steam generating device  50 . A steam discharge port  52   a  is formed at the other side of the housing  82 . The steam discharge port  52   a  is connected to the steam hose  53 , to supply steam from the steam hose  53  to the drum  20 . 
     The heater  55  is installed on the bottom of the upper housing  82  such that it is completely submerged under water when water is introduced into the steam generating device  50 . Thus, the heater  55  operates in a state of being submerged under water. To this end, a water level sensor  60  is installed at one side of the upper housing  82 , to sense a water level of the steam generating device. Since the water level sensor  60  measures the level of water stored in the steam generating device  50 , the amount of water stored in the steam generating device can be maintained at an appropriate level. That is, when the water level of the steam generating device  50  is lower than a first reference value (low water level), the water supply valve  15  is opened to supplement water. On the other hand, when the water level of the steam generating device  50  reaches a second reference (high water level), the water supply valve  15  is closed. In this case, the heater  55  operates to generate steam. 
     A temperature sensor  57  is also installed to measure the temperature of water heated by the heater  55  and the temperature of steam generated in accordance with the heating operation of the heater  55 . The temperature sensor  57  measures the internal temperature of the steam generating device, in order to cut off the supply of electricity to the heater  55  when the measured temperature is higher than a reference value, and thus to prevent the heater  55  from being over-heated. 
     Hereinafter, the water level sensor  60  will be described in detail. 
     The water level sensor  60  includes a receptacle housing  61  forming an appearance of the water level sensor  60 . The receptacle housing  61  is fixedly mounted to the steam generating device  50 . The water level sensor  60  also includes electrodes arranged in the receptacle housing  61  such that they extend downwardly, to sense the level of water stored in the steam generating device  50 . The electrodes  62 ,  63 , and  64  are positioned at predetermined levels from the bottom of the lower housing  81 , in order to sense the level of water stored in the steam generating device  50 . The electrodes comprise at least a common electrode  62  functioning as a reference electrode for sensing a water level, a low-water-level electrode  63  for sensing a low water level, and a high-water-level electrode  64  for sensing a high water level. The common electrode  62  preferably has a length equal to or longer than the length of the low-water-level electrode  63 . 
     Meanwhile, there is a possibility that, when water supplied through the water supply port  52   b  is splashed, and attached to the electrodes  62 ,  63 , and  64 , the water level sensor  60  may malfunction. Furthermore, it is difficult to completely prevent generation of vibration during operation of the washing machine. For this reason, the steam generating device  50  may also vibrate during operation of the washing machine, so that the water stored in the steam generating device  50  may roll. 
     Due to the above-mentioned factors, the water level sensor  60  may malfunctions. In order to prevent the water level sensor  60  from malfunctioning, a receptacle  70  is provided. The receptacle  70  is configured to enclose the electrodes  62 ,  63 , and  64 , and to have an open bottom. The receptacle  70  also preferably has an opening  70   s.    
     However, the above-mentioned conventional steam generating device and the washing machine equipped with the same have the following problems. 
     Since the conventional steam generating device has a substantially rectangular shape having a small height L 1  and a large width L 2 , as shown in  FIG. 4 , it is difficult to install the steam generating device  50  in the washing machine. This is because, although the steam generating device  50  is typically installed in an upper portion of the washing machine, in detail, in a space defined between the cabinet  10  and the tub  20 , the space between the tub  20  and the steam generating device  50  is relatively small. 
     In the space defined between the cabinet  10  and tub  20 , a valve, hanging springs, etc. are also installed. For this reason, the space for installing the steam generating device  50  may be insufficient. As a result, it is difficult to install and repair the steam generating device  50 . 
     Furthermore, although the steam generating device  50  is in an installed state, the steam generating device  50  may interfere with other elements of the washing machine when the washing machine is moved because the spacing t between the steam generating device  50  and the tub  20 . As a result, the steam generating device  50  may be damaged. Since the spacing t between the steam generating device  50  and the tub  20  is relatively small, they may strike against each other due to vibrations generated during operation of the washing machine. As a result, the steam generating device  50  may be damaged. 
     In addition, it is required to enhance the performance of the steam generating device  50 , for example, the amount of water used, energy efficiency, steam generating time, security, etc. 
     Meanwhile, when water boils in accordance with the operation of the steam generating device  50 , air bubbles are abruptly generated. The generated air bubbles may be attached to the electrodes  62 ,  63 , and  64 , thereby causing the water level sensor  60  to malfunction. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention is directed to a steam generating device and a washing machine having the same that substantially obviate one or more problems due to limitations and disadvantages of the related art. 
     An object of the present invention is to provide a steam generating device, which can be more easily installed, and a washing machine having the steam generating device. 
     Another object of the present invention is to provide a steam generating device, which can enhance the performance thereof, and can enhance the performance of a washing machine, to which the steam generating device is applied, and a washing machine having the same. 
     Still another object of the present invention is to provide a steam generating device, which can prevent malfunction of a water level sensor included in the steam generating device, and a washing machine having the same. 
     Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
     To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a steam generating device comprises: a lower housing including a main portion for receiving a heater, and connecting portions extending outwardly from the main portion, the lower housing defining a water chamber for containing water; an upper housing connected to the connecting portions, the upper housing defining a steam chamber for containing steam; a water level sensor for sensing a level of water contained in the water chamber; and a receptacle for protecting the water level sensor, the receptacle including an opening for allowing water to be introduced into the receptacle, wherein the receptacle is spaced apart from the heater by a distance equal to or longer than a distance from the heater to an inner surface of the main portion. 
     Preferably, the water chamber has a vertical length relatively longer than a horizontal length of the water chamber. Preferably, the steam chamber has a horizontal length relatively longer than the horizontal length of the water chamber. 
     Preferably, the steam generating device further comprise a rib provided at an inner surface of the lower housing, to prevent air bubbles from flowing into the receptacle. 
     Preferably, the rib is protruded toward a bottom of the receptacle. More preferably, the rib is integrally formed at the inner surface of the lower housing. 
     The receptacle may include a long barrier wall arranged substantially in parallel to the water level sensor, and a pair of short barrier walls each having a first end connected to the long barrier wall and a second end connected to an inner wall surface of the upper housing. 
     Preferably, a first opening is formed at a lower end of the long barrier wall, and a second opening is formed at one side of each short barrier wall. 
     The long barrier wall defines an outer surface of the receptacle. 
     In this case, preferably, the steam generating device further comprises a rib provided at an inner surface of the lower housing, to prevent air bubbles from flowing inside the long barrier wall. 
     In this case, preferably, the rib is protruded toward the long barrier wall such that a first opening is defined between the rib and the long barrier wall. More preferably, the rib is integrally formed at the inner surface of the lower housing. 
     In another aspect of the present invention, a steam generating device comprises: a lower housing including a main portion for receiving a heater, and connecting portions extending outwardly from an end of the main portion, the lower housing defining a water chamber for containing water; an upper housing connected to the connecting portions, the upper housing defining a steam chamber for containing steam; a water level sensor arranged over one of the connecting portions, to sense a level of water contained in the water chamber; and a rib extending from the end of the main portion toward the upper housing. 
     In accordance with the above-described configuration, it is possible to easily install the steam generating device, to enhance the performances of the steam generating device and washing machine, and to effectively prevent air bubbles from being introduced into the receptacle. 
     It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings: 
         FIG. 1  is a perspective view illustrating a structure of a conventional drum washing machine; 
         FIG. 2  is a perspective view illustrating the steam generating device of  FIG. 1 ; 
         FIG. 3  is a partially-broken perspective view illustrating the steam generating device of  FIG. 2 ; 
         FIG. 4  is a schematic view for explaining an installation condition of the steam generating device shown in  FIG. 1 ; 
         FIG. 5  is a schematic view for explaining the principle of a steam generating device according to the present invention, corresponding to  FIG. 4 ; 
         FIG. 6  is a perspective view illustrating a concrete embodiment of the steam generating device shown in  FIG. 5 ; 
         FIG. 7  is a bottom view illustrating an upper housing shown in  FIG. 6 ; 
         FIG. 8  is a sectional view corresponding to  FIG. 6 ; 
         FIG. 9  is a schematic view illustrating an installed state of an inverse flow preventing member according to the present invention; and 
         FIG. 10  is a schematic view illustrating an installed state of a safety valve according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention now will be described more fully hereinafter with reference to the accompanying figures, in which embodiments of the invention are shown. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts, and no repeated description thereof will be given. 
       FIG. 5  is a schematic view for explaining the principle of a steam generating device according to the present invention.  FIG. 5  corresponds to  FIG. 4 .  FIG. 6  is a perspective view illustrating a concrete embodiment of the steam generating device shown in  FIG. 5 .  FIG. 7  is a bottom view illustrating an upper housing shown in  FIG. 6 .  FIG. 8  is a sectional view corresponding to  FIG. 6 . 
       FIG. 9  is a schematic view illustrating an installed state of an inverse flow preventing member according to the present invention.  FIG. 10  is a schematic view illustrating an installed state of a safety valve according to the present invention. 
     Hereinafter, the principle of the steam generating device according to the present invention will be described with reference to  FIG. 5 . 
     The steam generating device  100  according to the illustrated embodiment of the present invention includes a lower housing defined with a water chamber W, in which a heater  200  for heating water is installed. The steam generating device  100  also includes an upper housing defined with a steam chamber S arranged over the water chamber W. The steam chamber S contains steam generated in accordance with the heating of water. 
     Water contained in the water chamber W is heated by the heater  200 , thereby generating steam. The generated steam is temporarily contained in the steam chamber S, and is then outwardly discharged from the steam chamber S through a steam discharge port formed at the steam chamber S. 
     In the conventional steam generating device  50 , as shown in  FIG. 4 , the water chamber W has a vertical length L 3  relatively shorter than a horizontal length L 2  because the steam generating device  50  has a rectangular shape. 
     That is, in the conventional steam generating device  50 , the heater  55  is horizontally arranged, and the vertical length L 3  of the water chamber W is only about the thickness of the heater  55 . In the conventional case, accordingly, the steam generating device  50  has an increased horizontal length to satisfy a required amount of water in the steam generating device  50 . 
     On the other hand, in accordance with the present invention, the water chamber W has a vertical length L 4  substantially longer than a horizontal length L 5 . 
     Accordingly, the heater  200  extends substantially in a vertical direction in the water chamber W. As shown in  FIG. 5 , the vertical length of the water chamber W may substantially correspond to a length L 4   a , namely, the vertical extension length of the heater  200 . However, since it is preferred that water be contained in the water chamber W to a level higher than the top of the heater  200 , it is assumed, in the following description, that the vertical length of the water chamber W corresponds to “L 4 ”. However, there is no contradiction or problem caused by this assumption because the difference between “L 4 ” and “L 4   a ” is relatively small, and the amount of water contained in the water chamber W to the level L 4   a  is a main portion of the total amount of water contained in the water chamber W. For the same reason, it is also assumed that the horizontal length of the water chamber W corresponds to the width of a portion of the water chamber W, in which the main portion of the total water amount is contained, namely, “L 5 ”. 
     Hereinafter, the advantages of the steam generating device  100  according to the illustrated embodiment of the present invention will be described. 
     It is possible to reduce the horizontal length L 5  of the water chamber W, as compared to conventional cases, while containing the same amount of water. Accordingly, it is possible to reduce the interference between the tub  20  and the steam generating device  100 . Through an experiment, it was found that, in the steam generating device  100  according to an exemplary embodiment of the present invention, it is possible to reduce the amount of water used to generate the same amount of steam as the conventional cases, and the steam generating time, and thus to reduce the size of the steam generating device  100 . 
     Meanwhile, it is preferred that the horizontal length L 6  of the steam chamber S be relatively longer than the horizontal length L 5  of the water chamber W. That is, although it is possible to reduce the horizontal length L 6  of the steam chamber S, as compared to the conventional cases, it is preferred that the horizontal length L 6  of the steam chamber S be equal to or slightly shorter than those of the conventional cases. This is because a water supply port and a steam discharge port are typically formed at the steam chamber S, and a water level sensor, a temperature sensor, etc. are also mounted to the steam chamber S. 
     When the vertical length L 4  of the water chamber W is relatively longer than the horizontal length L 5 , as described above, it is also preferred that the water chamber W be arranged substantially at a central portion of the steam chamber S, as shown in  FIG. 5 . 
     Hereinafter, a concrete embodiment of the steam generating device  100  shown in  FIG. 5  will be described with reference to  FIG. 6 . 
     The steam generating device  100  includes a lower housing  110  and an upper housing  120 . The upper housing  120  has a horizontal length longer than the horizontal length of the lower housing  110 . The lower housing  110  includes a portion in which the heater  200  is mounted, which contains a main portion of the total amount of water in the water chamber W, and which has a vertical length longer than a horizontal length. This portion will be referred to as a “main portion  111 ”, for the convenience of description ( FIG. 8 ). The lower housing  110  also includes portions extending from the main portion  111  in opposite lateral directions, and connected to the upper housing  120 . These portions will be referred to as “connecting portions  112  and  114 ”, for the convenience of description ( FIG. 8 ). It is preferred that the main portion of water in the water chamber W be present in the main portion  111  of the lower housing  110 , and the remaining small portion of water in the water chamber W be present in the connecting portions  112  and  114 . It is also preferred that the connecting portions  112  and  114  be inclined toward the main portion  111 . In accordance with this structure, it is possible to prevent foreign matter such as lime from being deposited over electrodes of a water level sensor arranged in the connecting portions  112  and  114 . 
     Since the pressure and temperature of steam generated in the water chamber W are relatively high, as compared to conventional cases, it is preferred that the lower and upper housings  110  and  120  be made of a material capable of withstanding high pressure and temperature. In this regard, it is preferred that the lower and upper housings  110  and  120  be connected using vibration fusing, rather than thermal fusing. 
     Hereinafter, the upper housing  120  defined with the steam chamber S will be described with reference to  FIGS. 7 to 9 . 
     A water supply port  122  and a steam discharge port  124  are formed at the upper housing  120 . Preferably, the housing  120  has a protruded portion, to form the water supply port  122  and steam discharge port  124  at the protruded portion. 
     A water level sensor  300  and a temperature sensor  400  are arranged in the upper housing  120 . The water level sensor  300  is arranged at a position spaced apart from the water supply port  122  by a certain distance. It is preferred that the water level sensor  300  be arranged at a position misaligned from a water supply direction of the water supply port  122 . 
     In this case, it is possible to prevent water splashed while being discharged from the water supply port  122  from coming into contact with the water level sensor  300 , and thus to prevent the water level sensor  300  from malfunctioning. 
     It is also preferred that the water level sensor  300  be arranged adjacent to an inner wall surface of the upper housing  120 , namely, be arranged over the connecting portion  114  of the lower housing  110 , rather than the main portion  111 . In other words, it is preferred that the water level sensor  300  be arranged to be spaced apart from the main portion  111  of the water chamber W by a certain distance. 
     In this case, it is possible to effectively prevent water splashed and air bubbles generated during a heating operation of the heater  200 , in particular, in an initial heating stage of the heater  200  from coming into direct contact with the water level sensor  300 , and thus to effectively prevent the water level sensor  300  from malfunctioning due to the splashed water and air bubbles. 
     The steam generating device  100  according to the illustrated embodiment of the present invention includes a receptacle  320  for protecting the water level sensor  300 . The receptacle  320  is arranged in the upper housing  120  such that the outer surface of one side wall of the receptacle  320  arranged toward the center of the upper housing  129  is substantially aligned with an inner surface  111   a  of the main portion  111  of the lower housing  110 , or is arranged outside the inner surface  111   a  with respect to the heater  200 . 
     In this case, it is preferred that a rib  500  be provided at the inner surface  111   a  of the main portion  111 , to prevent air bubbles from flowing into the receptacle  320 . 
     It is also preferred that the rib  500  be integrally formed at the inner surface  111   a  of the main portion  111 , and be protruded toward an opening formed at the bottom of the receptacle  320 . 
     When the outer surface of one side wall of the receptacle  320  is arranged outside the inner surface  111   a  of the main portion  111 , and the rib  500  is provided, as described above, it is possible to prevent air bubbles generated during a water heating operation of the heater  200  from flowing into the receptacle  320 . 
     Hereinafter, the structure for preventing air bubbles from flowing into the receptacle  320  will be described in more detail. 
     The receptacle  320  according to the illustrated embodiment of the present invention may include barrier walls. 
     The barrier walls may be formed separately from the steam generating device  100 , as in conventional cases. However, it is preferred that the inner wall of the upper housing  120  constitutes a part of the barrier walls of the receptacle  320 . 
     That is, the barrier walls of the receptacle  320  may include a long barrier wall  324  arranged in parallel to the water level sensor  300 , to form a longitudinal surface of the receptacle  320 , and a pair of short barrier walls  322  each connected, at one end thereof, to the long barrier wall  324 , and connected, at the other end thereof, to the inner wall surface of the upper housing  120  such that the short barrier walls  322  form opposite lateral surfaces of the receptacle  320 , respectively. 
     Preferably, the long barrier wall  324  is arranged over the connecting portion  114  of the lower housing  110 . In particular, it is preferred that the long barrier wall  324  be arranged over the rib  500  extending upwardly from the main portion  111  of the water chamber W. 
     The first short barrier wall  322  may be arranged at one side of the heater  200 , whereas the second short barrier wall  323  may be arranged at the other side of the heater  200 . 
     In order to allow water to be introduced into the receptacle  320 , it is preferred that a first opening  327  be formed at a lower end of the long barrier wall  324 , and second openings  326  be formed at the other-side ends of the short barrier walls  322 . 
     In order to prevent air bubbles from being introduced inside the long barrier wall  324 , and thus into the receptacle  320 , it is preferred that the long barrier wall  324  be substantially aligned with the inner surface  111   a  of the main portion  111 , or be arranged at a position spaced apart from the heater  200  by a longer distance than that of the inner surface  111   a . It is also preferred that the rib  500  be provided at the inner surface  111   a  of the main portion  111 , to prevent air bubbles from flowing inside the long barrier wall  324 . 
     In this case, it is preferred that the rib  500  be integrally formed with the inner surface  111   a  of the main portion  111  while being protruded toward the first opening  327 . 
     When the outer surface of the long barrier wall  324  is arranged at a position spaced apart from the heater  200  by a longer distance than that of the inner surface  111   a  of the main portion  111 , and the rib  500  is protruded toward the first opening  327 , as described above, it is possible to guide air bubbles generated in the water chamber W by the heater to flow outside the receptacle  320 , namely, outside the long barrier wall  324 . 
     Accordingly, it is possible to prevent air bubbles from being introduced into the receptacle  320 , and thus to prevent the water level sensor  300  from malfunctioning due to air bubbles. 
     Meanwhile, the water level sensor  300  includes a common electrode  312 , a low-water-level electrode  314 , and a high-water-level electrode  316 . The high-water-level electrode  316  is spaced apart from the low-water-level electrode  314  by a certain distance. 
     For the water level sensor  300 , a standard product, which includes a common electrode  312 , a low-water-level electrode  314 , and a high-water-level electrode  316   a , is commercially available. Accordingly, a general water level sensor assembly, which has such a configuration, may be used in the present invention, without any modification. In this case, however, it is preferred that a separate high-water-level electrode  316  be used, in place of the high-water-level electrode  316   a  of the general water level sensor assembly. 
     In this case, a high-water-level electrode receiver  318  is provided at a position spaced apart from the water level sensor  300 , to receive the high-water-level electrode  316 . Preferably, the high-water-level electrode receiver  318  has a cylindrical barrier wall structure. In accordance with the provision of the high-water-level electrode receiver  318 , it is possible to prevent the water level sensor  300  from malfunctioning due to water drops attached between the low-water-level electrode  314  and the high-water-level electrode  316 . 
     As described above, the steam discharge port  124  is formed at the upper housing  120 , to discharge steam. A separator  420  is arranged at the steam discharge port  124 , in order to separate the region, through which steam is outwardly discharged, from other regions. 
     Water and air bubbles are severely splashed when the water is heated in the water chamber W, in particular, in an initial heating stage. The separator  420  prevents the splashed water from being introduced into the drum through the steam discharge port  124 . When the splashed water is introduced into the drum, spots may be formed on the laundry. The separator  420  avoids such a phenomenon. 
     The separator  420  may have various structures, as long as it has a hole communicating with the steam discharge port  124  therein, to receive steam from the steam discharge port  124 . Preferably, the separator  420  has a barrier wall structure. In this case, it is preferred that the barrier wall structure has openings  421  to receive steam. 
     Although there is no limitation on the shape of the openings  421 , it is preferred that the openings  421  be arranged in a longer-axis direction. It is also preferred that the openings  421  be spaced apart from the steam discharge port  124  by a certain distance. 
     The barrier wall structure includes a first barrier wall  424  substantially facing the steam discharge port  124 , and a second barrier wall  422  extending from an inner surface of the upper housing  120  toward the first barrier wall  424 . Although the first and second barrier walls  424  and  422  may be integrally formed, it is preferred that the barrier wall structure includes one first barrier wall  424  and a pair of second barrier walls  422  separated from the first barrier wall  424  such that an opening  421  is defined between the first barrier wall  424  and each second barrier wall  422 . In this case, it is also preferred that the first barrier wall  424  be arranged over the connecting portion  112  of the water chamber W, rather than the main portion  111  of the water chamber W. 
     An auxiliary separator  430 , for example, a barrier wall, may be arranged outside the separator  420 . Preferably, the barrier wall of the auxiliary separator  430  is arranged adjacent to the openings  421  of the separator  420 . Also, It is preferred that the barrier wall of the auxiliary separator  430  do not come into contact with the inner wall surface of the steam generating device  100 . 
     Meanwhile, water is supplied to the water chamber W via a water supply line including, for example, the water supply hose or water supply port  122 . Steam from the steam chamber S is discharged into the drum via a steam discharge line including, for example, the steam discharge port  124  and steam hose. 
     Preferably, a reverse flow preventing member is arranged in at least one of the water supply line and steam discharge line, to prevent water and steam from flowing reversely. 
     For the reverse flow preventing member, various members may be used, as long as they have a reverse flow preventing function. For example, a one-way valve may be used for the reverse flow preventing member. However, it is preferred that, for the reverse flow preventing member, a nozzle-shaped flexible member  600  be used, as shown in  FIG. 9 , because the reverse flow preventing member is arranged in the water supply hose, water supply port  122 , water discharge port  124 , or steam discharge hose, which has a relatively-small diameter. A slit  610  is formed at a nozzle portion of the flexible member  600 . 
     Meanwhile, as shown in  FIG. 10 , a safety valve  700  is preferably arranged at a certain position of the steam discharge line. The safety valve  700  is automatically opened when the pressure of steam passing through the steam discharge line is higher than a predetermined level. The steam hose, which is designated by reference numeral “ 53 ” in  FIG. 10 , may be branched to form a branch pipe  53   a , and the safety valve  700  may be arranged in the branch pipe  53   a.    
     When no steam is supplied to the drum due to a problem occurring in the steam supply line, an excessive pressure is applied to the steam supply line. In this case, the safety valve  700  is automatically opened to outwardly discharge steam from the steam supply line. 
     A draining member  115  is provided at the water chamber W, as shown in  FIG. 8 , to outwardly drain water from the water chamber W. An opening/closing member  113  is arranged at the draining member  115 , to open or close the draining member  115 . When the opening/closing member  113  is opened, water from the water chamber W can be outwardly discharged. As the steam generating device  100  is continuously used for a prolonged period of time, foreign matter such as lime is accumulated in the steam generating device  100 . In this case, the draining member  115  is opened to outwardly drain water from the water chamber W, and thus to discharge the accumulated foreign matter, together with the water. Accordingly, it is possible to avoid the accumulation of foreign matter. 
     The opening/closing member  113  may be a drain cap which can be manually opened or closed by the user or operator. Alternatively, the opening/closing member  113  is configured to be automatically opened or closed. For example, a solenoid valve may be used. Also, the opening/closing member  113  may be configured using a siphon principle. 
     Although the present invention has been described in conjunction with the steam generating device according to an exemplary embodiment of the present invention, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. 
     The steam generating device having the above-described configuration according to the present invention and the washing machine having the same provide the following effects. 
     First, it is possible to more easily install the steam generating device because the water chamber of the steam generating device has a vertical length shorter than a horizontal length. 
     Second, it is possible to enhance the performances of the steam generating device and washing machine because a desired amount of steam can be generated within a reduced time, using a reduced amount of water. 
     Third, it is possible to prevent air bubbles from flowing into the receptacle, and thus to efficiently prevent the water level sensor from malfunctioning because the outer surface of one side wall of the receptacle is arranged outside the inner surface of the lower housing, and a rib is provided at the inner surface of the lower housing. 
     Fourth, it is possible to efficient prevent water and steam from flowing inversely in accordance with the present invention. Also, there is an improvement in security because the safety valve operates when an excessive pressure is applied to the steam supply line due to a problem occurring in the steam supply line. 
     Fifth, in accordance with the present invention, it is possible to water from the steam generating device from being introduced into the drum, and thus to prevent spots from being formed on the laundry.