Abstract:
A laundry machine is disclosed. The laundry machine includes a drum in which laundry is put, a steam generator to generate steam, a water supply line connected to the steam generator, a steam line connected to the steam generator, and a valve placed in the steam line, wherein the valve is controlled to block the steam line to prevent water from flowing from the steam generator to the drum.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of Korean Patent Application No. 10-2007-0096565, filed on Sep. 21, 2007, which is hereby incorporated by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a laundry machine to wash or dry laundry. The laundry machine includes a washing machine, a dryer, a drying and washing machine or the like. Recently, the laundry machine includes a steam generator. The present invention relates more particularly to a laundry machine having a steam generator. 
         [0004]    2. Discussion of the Related Art 
         [0005]    Generally, washing machines include a pulsator type washing machine and a drum washing machine. Further, the washing machines also include a drying and washing machine which can perform both washing and drying. 
         [0006]    A dryer is an electric home appliance which generally dries washed laundry, mainly, clothes using high-temperature air. The dryer generally includes a drum which accommodates the laundry therein, a driving device which drives the drum, a heating unit which heats air introduced into the drum, a blower unit to make the heated air to flow into the drum, and the like. 
         [0007]    The dryers are classified into an electric dryer and a gas-type dryer according to an air heating method, i.e., a heating unit. The electric dryer heats air using electric resistance heat, and the gas-type dryer heats air using heat generated by gas combustion. In another way, the dryers can be classified into a condensation dryer and an exhaust dryer. In the condensation dryer, humid air which has been heat-exchanged with the laundry in the drum is circulated without being discharged to the outside, and the humid air is converted into condensed water in a separate condenser by heat exchange with outside air to be discharged to the outside. In the exhaust dryer, humid air which has been heat-exchanged with the laundry in the drum is directly discharged out of the dryer. 
         [0008]    A conventional laundry machine may include a steam generator. A washing machine using steam in the washing operation has a good washing performance. 
       SUMMARY OF THE INVENTION 
       [0009]    When water is supplied into the steam generator over a required level, water may overflow through a steam line. Particularly, when water is supplied into the steam generator through a faucet and a water supply valve, if the water supply valve is out of order, water can continuously flow into the steam generator, thereby causing overflow. In case of a dryer, overflowing water may be introduced into the drum and wet the laundry. Further, since the dryer generally does not have a drain line for discharging water out of a drum or a tub, differently from the washing machine, the problem becomes worse. 
         [0010]    Also in the washing machine, water can overflow the steam generator due to an error in the water supply to flow into the tub, thereby causing a problem. 
         [0011]    The present invention is related to a laundry machine that substantially obviates one or more problems due to limitations and disadvantages of the related art. 
         [0012]    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 can be learned from practice of the invention. The objectives and other advantages of the invention can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
         [0013]    An embodiment of the present invention comprises a drum in which laundry is put; a steam generator to generate steam; a water supply line connected to the steam generator; a steam line connected to the steam generator; and a valve placed in the steam line, wherein the valve is controlled to block overflowing water from the steam generator. 
         [0014]    In the above embodiment, water can be prevented from flowing to the drum through the steam line. 
         [0015]    The water supply line can be connected to a faucet and a water supply valve. In this case, even though water is over supplied to the steam generator due to a malfunction of the water supply valve or the like, the water does not flow into the drum by the valve installed on the steam line. However, when water is intended to be supplied to the drum through the steam line after passing through the steam generator, the valve installed on the steam line can be controlled according to the conditions. 
         [0016]    The valve installed on the steam line can be controlled according to a temperature of the steam generator. In this case, the temperature of the steam generator can be one of a temperature of a body of the steam generator, a temperature of atmosphere in the steam generator, and a temperature of water in the steam generator. 
         [0017]    When the temperature of the steam generator is equal to or larger than a preset temperature, the valve installed on the steam line can be controlled to be kept open. For example, the valve installed on the steam line which maintains a closed state can be controlled to be opened when the temperature of the steam generator reaches 100° C. When water is over supplied to the steam generator and overflows the steam generator, the temperature of the steam generator would be lower than the preset temperature. In this case, since the valve installed on the steam line is in a closed state, overflowing water does not flow into the drum through the steam line. 
         [0018]    Meanwhile, the valve installed on the steam line can be controlled to be opened after a predetermined period of time after the heater of the steam generator is turned on, instead of being controlled according to a temperature as described above. 
         [0019]    In this case, the valve installed on the steam line can be controlled to be closed at the same time when the water supply valve is closed as water supply into the steam generator is completed. Even though the water supply valve is not closed due to a malfunction, water is not introduced into the drum by being blocked by the valve installed on the steam line. 
         [0020]    Further, the valve installed on the steam line can be controlled according to an amount of water to be supplied into the steam generator. For example, if the amount of water supplied into the steam generator is equal to or larger than a preset amount, the valve is controlled to be closed. In this case, the preset amount can be set to be equal to or larger than an allowable water supply amount of the steam generator. Further, the preset amount can be set to be larger than a set amount by which water is supplied into the steam generator. 
         [0021]    The laundry machine can further include an instrument to measure an amount of water supplied into the steam generator. The instrument can be any device capable of detecting an amount of water supplied into the steam generator. 
         [0022]    For example, the instrument can include an impeller installed on the water supply line and a detection unit to detect the number of rotation of the impeller. Accordingly, if the impeller rotates by a preset number or more, the valve installed on the steam line is closed. 
         [0023]    Further, the instrument can include a water level sensor which senses a water level in the steam generator. The water level sensor senses a maximum allowable water level of the steam generator. If the maximum allowable water level is sensed by the water level sensor, the valve installed on the steam line can be controlled to be closed. In this case, the maximum allowable water level can be determined as a water level over which water is supplied to cause overflow through the steam line. 
         [0024]    The water level sensor can be configured to sense another preset level in the steam generator. For example, the water level sensor can be configured to sense a first water level, a second water level and the maximum allowable water level. If a water level reaches the second water level, the water supply valve is controlled to be closed. The first water level is provided to prevent the heater installed in the steam generator from being exposed above the surface of the water. For example, if a water level in the steam generator gradually decreases and then reaches the first water level, the heater can be controlled to be turned off in order to prevent from being overheated. 
         [0025]    Further, the valve installed on the steam line can be controlled according to time. For example, the valve can be controlled to be closed within a preset period of time after the water supply valve is closed as water supply into the steam generator is completed and, then, opened after a preset period of time. 
         [0026]    According to the present invention, even though water is over-supplied to the steam generator, the water can be prevented from flowing into the drum. Particularly, even when there is an error in the water supply, the water can be prevented from overflowing the steam generator and flowing into the drum. 
         [0027]    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 
         [0028]    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: 
           [0029]      FIG. 1  illustrates a laundry machine according to an embodiment of the present invention; 
           [0030]      FIG. 2  illustrates a cross-sectional view of the laundry machine shown in  FIG. 1 ; and 
           [0031]      FIG. 3  illustrates an enlarged configuration view showing essential portions of the laundry machine shown in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
         [0033]    Hereinafter, a laundry machine according to an embodiment of the present invention will be described with reference to  FIGS. 1 to 3 . For convenience, a top-loading, electric, condensation dryer is explained as an example, but the present invention is not limited thereto. 
         [0034]    A rotatable drum  20 , a motor  70  which drives the drum  20  and a belt  68  are installed inside a cabinet  10  forming an external appearance of the dryer. Further, a heater  90  (hereinafter, simply referred to as a “hot air heater”) which heats air to produce high-temperature air (hereinafter, referred to as “hot air”) and a hot air supply duct  44  which supplies hot air produced in the hot air heater  90  to the drum  20  are installed at specific positions of the cabinet  10 . Further, an exhaust duct  80  which discharges humid air that has been heat-exchanged with laundry in the drum  20 , and a blower unit  60  which sucks the humid air are installed in the cabinet  10 . Meanwhile, a steam generator  200  is installed at a specific position of the cabinet  10  to generate high-temperature steam. Although an indirect drive type dryer which rotates the drum  20  using the motor  70  and the belt  68  is shown and described in this embodiment, the present invention is not limited thereto. That is, a direct drive type dryer which directly rotates the drum  20  by a motor directly connected to the rear surface of the drum  20  can be applied to the present invention. 
         [0035]    The respective components are described in detail below. 
         [0036]    The cabinet  10  forming an external appearance of the dryer includes a base  12  forming a bottom surface, a pair of side covers  14  vertically installed on the base  12 , a front cover  16  and a rear cover  18  respectively installed on the front and rear surfaces of the side covers.  14 , and a top cover  17  positioned at an upper portion of the side covers  14 . A control panel  19  having various control switches and the like is generally disposed on the top cover  17  or the front cover  16 . A door  164  is installed on the front cover  16 . The rear cover  18  includes a suction port  182  which introduces outside air and an exhaust hole  184  serving a final passage to discharge air in the drum  20  to the outside. 
         [0037]    An inner space of the drum  20  serves as a drying chamber to perform a drying operation, and the drum  20  has a lift  22  therein. 
         [0038]    Meanwhile, a front supporter  30  and a rear supporter  40  are installed between the drum  20  and the cabinet  10  (the front cover  16  and the rear cover  18 ). The drum  20  is rotatably installed between the front supporter  30  and the rear supporter  40 . Sealing members (not shown) are installed between the front supporter  30  and the drum  20  and between the rear supporter  40  and the drum  20 , respectively, to prevent leakage. That is, the front supporter  30  and the rear supporter  40  close the front and rear surfaces of the drum  20  to form the drying chamber and serve to support a front end and a rear end of the drum  20 . 
         [0039]    An opening is formed on the front supporter  30  such that the drum  20  communicates with the outside of the dryer. The opening is selectively opened and closed by the door  164 . Further, a lint duct  50  serving as a passage for discharging air of the drum  20  to the outside is connected to the front supporter  30 , and a lint filter  52  is installed in the lint duct  50 . The lint duct  50  is connected to one side of the blower unit  60 , and the other side of the blower unit  60  is connected to the exhaust duct  80 . The exhaust duct  80  communicates with the exhaust hole  184  disposed on the rear cover  18 . Accordingly, when the blower unit  60  is operated, air in the drum  20  is discharged to the outside through the lint duct  50 , the exhaust duct  80  and the exhaust hole  184 . In this case, foreign matter such as nap is filtered by the lint filter  52 . Generally, the blower unit  60  includes a blower  62  and a blower housing  64 , and the blower  62  is connected to and driven by the motor  70  for driving the drum  20 . An opening  42  generally having a number of through holes is formed on the rear supporter  40 . The opening  42  is connected to the hot air supply duct  44 . The hot air supply duct  44  communicates with the drum  20  to serve as a passage for supplying hot air to the drum  20 . Accordingly, the hot air heater  90  is installed at a specific position of the hot air supply duct  44 . 
         [0040]    Meanwhile, the steam generator  200  is installed at a specific position of the cabinet  10  to generate steam and supply the steam into the drum  20 . The steam generator  200  is described in detail below with reference to  FIG. 3 . 
         [0041]    The steam generator  200  includes a water tank  210  for accommodating water therein, a heater  240  mounted in the water tank  210 , a water level sensor  260  which measures a water level of the steam generator  200 , and a temperature sensor  270  which measures a temperature of the steam generator  200 . The water level sensor  260  includes a common electrode  262 , a low water level electrode  264  and a high water level electrode  266 . The water level sensor  260  detects a high water level and a low water level according to whether the common electrode  262  is electrically connected to the high water level electrode  266  or whether the common electrode is electrically connected to the low water level electrode  264 . 
         [0042]    A water supply hose  220  for supplying water is connected to one side of the steam generator  200  and a steam hose  230  for discharging steam is connected to the other side of the steam generator  200 . It is preferable to provide a nozzle  250  at a leading end of the steam hose  230 . A faucet and a water supply valve  281  are connected to one end of the water supply hose  220 . A leading end portion of the steam hose  230  or the nozzle  250 , that is, a steam discharge port, is disposed at a specific position of the drum  20  to spray steam into the drum  20 . Although the nozzle  250  is disposed at the front of the drum  20  in this embodiment, the nozzle  250  can be installed on the rear supporter  40 . 
         [0043]    Further, a valve  282  is installed on the steam hose  230 . A controller opens the water supply valve  282  to supply water to the steam generator  200 . When it is determined that the water level in the steam generator  200  reaches a high water level based on a signal of the water level sensor  260 , the controller closes the water supply valve  282 . In this case, the valve  282  installed on the steam hose is also closed. 
         [0044]    Then, the controller turns on the heater  240  to heat water in the steam generator  200 . As time goes by, when an inner temperature of the steam generator  200  increases and reaches a preset temperature, the valve  282  installed on the steam hose  230  is opened. The steam generated in the steam generator  200  is supplied to the drum  20  through the steam hose  230 . 
         [0045]    Meanwhile, a flowmeter can be installed on the water supply hose to detect an amount of water supplied into the steam generator. Generally, the flowmeter is a conventional well-known impeller flowmeter. The amount of water supplied through the water supply hose is detected using the rotation number of the impeller. The controller receives a signal of the flowmeter and closes the water supply valve when the amount of water reaches a preset amount. 
         [0046]    Further, the water level sensor can be used. For example, if a high water level is sensed by a high water level terminal of the water level sensor, the valve installed on the steam hose is closed. In another way, a terminal capable of sensing a water level higher than the water level sensed by the high water level terminal (so-called ‘critical water level terminal’) can be further provided and used. If a critical water level is sensed by the critical water level terminal, the valve of the steam hose is closed. In this case, the critical water level can be set as a maximum allowable water level of the steam generator. 
         [0047]    The present invention relates to a laundry machine to wash or dry the laundry. According to the present invention, even though water is excessively supplied to the steam generator and overflow is generated, it is possible to prevent the water from flowing into the drum. Particularly, even when there is an error in the water supply, it is possible to prevent water from overflowing the steam generator and flowing into the drum. 
         [0048]    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.