Patent Publication Number: US-9428855-B2

Title: Washing machine

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Korean Patent Application No. 10-2012-0031026, filed on Mar. 27, 2012 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
     BACKGROUND 
     1. Field 
     Embodiments of the present disclosure relate to a washing machine provided with a control panel assembly on which a speaker and a display unit in a touch screen are provided. 
     2. Description of the Related Art 
     A washing machine is a machine to wash clothes by use of electric power. In general, a washing machine includes a tub to accommodate wash water, a drum rotatably installed at an inside the tub, and a motor to drive a rotating operation of the drum. 
     In a state of having the laundry and the detergent water input in the drum, if the drum is rotated by the motor, the dirt on the laundry is removed by friction among the laundry, the drum and the detergent water. 
     According to the technology development in recent years, a user is accustomed to operating a machine through a display unit in a touch screen scheme. 
     In addition, a technology has been developed to represent the operating status of a machine through a human voice or real music as well as through a simple buzzer sound or a simple melody. 
     Numerous studies have been conducted to apply such a technology to a washing machine for user&#39;s convenience. 
     SUMMARY 
     Therefore, it is an aspect of the present disclosure to provide a washing machine having a structure capable of easily transmitting sound, which is generated from a speaker, while preventing moisture from being infiltrated to the inside a control panel assembly. 
     Additional aspects of the disclosure 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 disclosure. 
     In accordance with one embodiment of the present disclosure, a washing machine includes a cabinet, a control panel, a display unit, a speaker and a speaker hole. The control panel may be disposed on a front surface of the cabinet. The display unit may be installed on the control panel such that a front surface of the display unit is exposed through a front of the control panel. The speaker may be disposed at a rear of the control panel. The speaker hole may be formed through the control panel so that sound being generated from the speaker is transmitted to outside the control panel. The speaker hole may be disposed to be spaced apart from the speaker. 
     The washing machine may further include a shielding unit formed at a rear surface of the control panel to cover a rear of the speaker hole. 
     The shielding unit may include at least one side shielding film protruding from the control panel to the rear of the control panel so as to block moisture from being introduced to the inside the control panel through the speaker hole. 
     The side shielding film may include a first-side shielding film and a second-side shielding film that are formed at both sides of the speaker hole, respectively. 
     The at least one of the first-side shielding film and the second-side shielding film may be inclined such that the first-side shielding film and the second-side shielding film are adjacent to each other while coming together from the speaker to the speaker hole. 
     The side shielding film may be configured to guide the sound, which is generated from the speaker, to the speaker hole. 
     The shielding unit may further include a rear shielding film provided in parallel to the control panel so as to block the moisture from being introduced to the inside the control panel. 
     The rear shielding film may be supported by the at least one side shielding film. 
     The shielding unit may include a drain hole that is formed while being open through a lower end of the shielding unit to discharge moisture that is input through the speaker hole. 
     The washing machine may further include a speaker housing which is installed at the rear surface of the control panel and on which the speaker is mounted. 
     The speaker housing may include a guide rib that protrudes toward a front of the speaker housing. 
     The guide rib may be provided to guide the sound, which is generated from the speaker, toward the speaker hole. 
     The speaker may be mounted at a rear side of the speaker housing, and the speaker housing may include an opening that is open through a part of the speaker housing. 
     The guide rib may be provided adjacent to the opening. 
     The display unit may include a display unit in a touch screen scheme. 
     The display unit may include a touch sensor. 
     In accordance with another aspect of the present disclosure, a washing machine includes a cabinet, and a control panel assembly. The control panel assembly may be disposed on a front surface of the cabinet. The control panel assembly may include a control panel, a speaker, a speaker hole and a guide rib. The control panel may form an external appearance of the control panel assembly. The speaker may be disposed at a rear of the control panel. The speaker hole may be formed while being open through a part of the control panel. The guide rib may be configured to guide sound, which is generated from the speaker, toward the speaker hole. 
     The speaker hole may be located at a position lower than a position of the speaker. 
     The guide rib may include a first guide rib that protrudes from a rear surface of the control panel. 
     The control panel assembly may further include a speaker housing allowing the speaker to be mounted on a rear side thereof. 
     The guide rib may include a second guide rib protruding from a front surface of the speaker housing. 
     The speaker housing may include at least one fixing clip configured to fix the speaker to a rear surface of the speaker housing. 
     The speaker may include a fixing protrusion that is configured to be fixed to the fixing clip. 
     As described above, a washing machine in accordance with the present disclosure can easily transmit the sound, which is transmitted from the speaker, through a speaker hole while preventing moisture from being penetrated to the inside the control panel assembly through the speaker hole. 
     A user convenience is provided through the display device in a touch screen scheme. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects of the disclosure will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a perspective view illustrating the configuration of a washing machine in accordance with an embodiment of the present disclosure. 
         FIG. 2  is a cross sectional view of the washing machine of  FIG. 1 . 
         FIG. 3  is a perspective view illustrating the configuration of a control panel assembly of the washing machine of  FIG. 1 . 
         FIG. 4  is an enlarged view illustrating a speaker housing shown on  FIG. 3 . 
         FIG. 5  is a cross sectional view illustrating the coupling relationship among a cover, a speaker housing and a speaker shown on  FIG. 3 . 
         FIG. 6  is a perspective view illustrating a configuration coupled at a rear of a housing shown on  FIG. 3 . 
         FIG. 7  is an enlarged view illustrating a speaker housing shown on  FIG. 6 . 
         FIG. 8  is a perspective view illustrating a washing machine in accordance with another aspect of the present disclosure. 
         FIG. 9  is a perspective view illustrating the configuration of a control panel assembly of the washing machine shown on  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. 
       FIG. 1  is a perspective view illustrating the configuration of a washing machine in accordance with an embodiment of the present disclosure.  FIG. 2  is a cross sectional view of the washing machine of  FIG. 1 . 
     Referring to  FIGS. 1 and 2 , a washing machine  1  includes a cabinet  10  forming the external appearance of the washing machine, a tub  20  disposed at an inside the cabinet  10 , a drum  30  rotatably disposed at an inside the cabinet  10 , and a motor  71  to drive the drum  30 . 
     An inlet  11  is formed at a front side of the cabinet  10  such that a laundry is input through the inlet  11  to the inside the drum  30 . The inlet  11  is open and closed by a door  12  installed at the front side of the cabinet  10 . 
     The tub  20  is supported by a damper  78 . The damper  78  connects a bottom surface of the inner side of the cabinet  10  to an outer surface of the tub  20 . 
     The tub  20  is provided at an upper side thereof with a water supply pipe  50  to supply wash water to the tub  20 . One side of the water supply pipe  50  is connected to a water supply valve  56 , and the other side of the water supply pipe  50  is connected to a detergent container  52 . 
     The detergent container  52  is connected to the tub  20  through a connection pipe  54 . Water being supplied through the water supply pipe  50  is supplied via the detergent container  52  to the inside the tub  20  together with detergent. 
     The tub  20  is provided at a lower side thereof with a drain pump  80  and a drain pipe that are configured to discharge water at an inside of the tub to the outside. 
     The drum  30  includes a cylindrical part  31 , a front side panel  32  disposed at a front of the cylindrical part  31 , and a rear side panel  33  disposed at a rear of the cylinder part  31 . The front side panel  32  has an opening  32   a  allowing a laundry to input and withdraw therethrough. A driving shaft  72  configured to transmit power of the motor  71  is connected to the rear side panel  33 . 
     A plurality of through-holes  34  is formed through a circumference of the drum  20  to circulate wash water. The interior space of the drum  30  communicates with the interior space of the tub  20 . 
     A plurality of lifters  35  is installed at an inner circumferential surface of the drum  30  such that the ascending and descending of the laundry is achieved when the drum  30  rotates. 
     The driving shaft  72  is disposed between the drum  30  and the motor  71 . One end of the driving shaft  72  is connected to the rear side panel  33  of the drum  30 , and the other end of the driving shaft  72  extends to the outside a rear wall of the tub  20 . As the motor  71  drives the driving shaft  72 , the drum  30  being connected to the driving shaft  72  rotates on the driving shaft  72 . 
     A bearing housing  73  is installed at the rear wall of the tub  20  so as to rotatably support the driving shaft  72 . The bearing housing  73  is formed of an aluminum alloy, and may be inserted into the rear wall of the tub  20  at the time of injection molding of the tub  20 . A plurality of bearings  74  are installed between the bearing housing  73  and the driving shaft  72  such that the driving shaft  72  is smoothly rotated. 
     At a lower side of the tub  20 , a drain pump  80  to discharge at the inside the tub  20  to the outside the cabinet  10 , a connection hose  82  connecting the tub  20  to the drain pump  80  such that water at an inside the tub  20  is introduced to the drain pump  80 , and a drain hose  84  configured to guide the water pumped by the drain pump  80  to the outside the cabinet  10 . 
     A dry apparatus  90  is mounted at the tub  20  such that air at an inside the tub  20  is supplied to the inside the tub  20  again after being dried. The drying apparatus  90  includes a drying duct  94  that is configured to circulate dry air while communicating with the front surface of the tub  10 . 
     During a wash cycle, the motor  71  rotates the drum  30  forward and backward at a low speed, and accordingly, the laundry at an inside the drum  30  repeatedly ascends and descends, thereby removing dirt from the laundry. 
     During a spin dry cycle, the motor  71  rotates the drum  30  in one direction at a high speed, so that water is separated from the laundry by a centrifugal force acting on the laundry. 
     When the drum  30  rotates during the spin dry cycle, if the laundry is positioned at a certain position without evenly distributed at an inside the drum  30 , an unbalance load occurs in the drum  30 , and thus the rotation motion of the drum  30  is unstable and the vibration and noise are generated. Accordingly, the washing machine  1  is provided with a balancer (not shown) to stabilize the rotation of the drum  30 . The balancer (not shown) is provided in one pair of balancers, one for each of the front side panel  32  and the rear side panel  33 . 
     Meanwhile, a control panel assembly  110  is provided at an upper portion of the front surface of the cabinet  10  for a user to control the operation of the washing machine  1 . 
       FIG. 3  is a perspective view illustrating the configuration of a control panel assembly of the washing machine of  FIG. 1 . 
     Referring to  FIG. 3 , the control panel assembly  100  includes a control panel  110  that forms the external appearance of the control panel assembly  100  and mounted at the upper portion of the front surface of the cabinet ( 10  in  FIG. 1 ) while being inclined. 
     A detergent container accommodating port  112  is formed through a part of the control panel  110  such that the detergent container  52  is detachable toward the inside the cabinet. 
     A display unit mounting port  111  is provided at a center of the control panel  110  while being penetratively formed through a part of the control panel  110  such that the display unit  150  is exposed to the front of the control panel  110 . 
     The display unit  150  outputs washing operation related information, such as operating information of the washing machine, details of a washing operation or the operation status of the wash cycle. According to an embodiment of the present disclosure, the display unit  150  may perform as an input function as well as a display function. 
     In a case that the display unit  150  is provided in a touch screen scheme, the display unit  150  may perform the input function as well as the display function. 
     The display unit  150  may include a touch sensor (not shown) to sense a touch by a user. The touch sensor (not shown) may be provided in a layer structure with a display panel (not shown) of the display unit  150 . 
     The touch sensor (not shown) is configured to convert the change in pressure applied to a certain position of the display unit  150  or the change in capacitance being generated in a certain position of the display unit  150  to an electric input signal. The touch sensor (not shown) may be configured to detect a pressure at the time of being touched, as well as the position and area touched. 
     The display unit  150  is mounted on the housing  120 . The housing  120  includes a display housing  130  on which the display unit  150  is mounted, and a speaker housing  140  on which the speaker  170  is mounted. 
     The display unit  150  is mounted at a front surface  131  of the display housing  130 , and a main board  160  is mounted at a rear surface (not shown) of the display housing  130 . The display unit  150  is electrically connected to the main board  160  through a cable  151 . The cable  151  may extend to the main board  160  by passing over the lower end of the display housing  130 . Alternatively, a through-hole  137  is formed through a part of the front surface  131  of the display housing  130 , so that the display unit  150  may be connected to the main board  160  through the cable  151  passing through the through-hole  137 . 
     The speaker housing  140  is disposed at a lateral side of the display housing  130  such that the speaker  170  is mounted on the speaker housing  140 . 
     The display housing  130  is integrally formed with the speaker housing  140 . According to another embodiment of the present disclosure, the display housing  130  and the speaker housing  140  may be separately formed from each other and assembled to each other. 
     The speaker  170  is connected to the main board  160 . 
     The speaker  170  is a type of an acoustic sound playback apparatus capable of replaying a melody, for example, a buzzer. Since the speaker  170  implements sound by vibrating a vibration plate or a vibration membrane, a wide range of sound and tone is generated, and thus various types of sound audible to humans are replayed as well as human voices. 
     Through the speaker  170 , at the time of the on/off of the washing machine and the start/stop/end of a wash cycle, or the selecting of the wash course and the selecting of a function of a washing operation, an alarm sound is generated. Such an alarm sound includes a constant melody sound as well as a sound of a constant tone. Further, since the speaker  170  is employed, the alarm sound may be generated using the human voice. 
     The sound generated by the speaker  170  is not limited thereto, and may include various types of sound. In addition to generating a sound to indicate the function and the operating status of the washing machine  1 , a music desired by a user may be replayed or various types of sound being transmitted from a terminal (not shown) may be replayed. 
     The speaker  170  is mounted at the rear surface of the speaker housing  140 . An opening  143  is formed at a portion of the speaker housing  140 , on which the speaker  170  is mounted, such that sound being generated from the speaker  170  passes through the opening  143 . 
     A guide rib  141  is formed around the opening  143  while protruding to the front of the speaker housing  140 . 
     A communication module  180  is connected to the main board  160 . 
     The washing machine  1  is connected to an outside Internet through the communication module  180 . The outside Internet being connected to the washing machine  1  includes various types of communication links, for example, a ZigBee communication network, a WIFI communication network, a Bluetooth communication network, a mobile communication network, a local-area network (LAN), a wide-area network (WAN), and a point to point telephone line connection. 
     The communication module  180  is configured to connect the washing machine  1  to the outside Internet, and may include a ZigBee communication module, a WIFI communication module, a Bluetooth communication module, and an AP module. 
     The terminal (not shown) is an apparatus designed to execute an exclusive Application (hereinafter, referred to as App) for performing a remote control setting of the washing machine while being connected to the communication module  180  mounted on the washing machine  1 , and the terminal may include all the devices connectable to the outside Internet. That is, the terminal (not shown) is an apparatus to transmit remote control information from a user such that the washing machine  1  is controlled in a remote method. 
     The terminal (not shown) includes smart phones, personal digital assistances (PDA), portable multimedia players (PMP), notebooks, and desktop computers, and may be provided with an input apparatus, such as a key, a button, a switch, and a touch pad so as to enable an input of the remote control information through manipulation by a user. In addition, the terminal (not shown) includes a device, for example, a digital camera and a camcorder, equipped with various functions implemented using various application programs. 
     In addition, an App is installed on the terminal (not shown) to proceed with the remote control setting of the washing machine  1 , and the App for the terminal (not shown) may be additionally installed depending on the use. 
       FIG. 4  is an enlarged view illustrating a speaker housing shown on  FIG. 3 .  FIG. 5  is a cross sectional view illustrating the coupling relationship among a cover, a speaker housing and a speaker shown on  FIG. 3 . 
     Referring to  FIGS. 4 and 5 , the speaker housing  140 , on which the speaker  170  is mounted, is mounted at the rear of the control panel  110 . 
     A speaker hole  115  is formed through a lower portion of a predetermined position of the control panel  110 , the predetermined position corresponding to the speaker  170 , so that the sound generated from the speaker  170  is transmitted to the front of the control panel  110 . 
     A shielding unit  118  is formed at a rear of the speaker hole  115  to prevent moisture being introduced through the speaker hole  115  from being infiltrated to the speaker  170  or the main board  160 . The shielding unit  118  includes a side shielding film  116  and a rear shielding film  117 . 
     At the rear surface of the control panel  110 , the side shielding film  116  is formed at both sides of the speaker hole  115  while protruding to the rear side. The side shielding film  116  may be provided in two units thereof, one for each side of the speaker hole  115 . 
     The two side shielding films  116  may be inclined so as to be adjacent to each other while coming together from the upper side to the lower side. Although one of the two side shielding films is illustrated as being inclined, the present disclosure is not limited thereto. Having both of the side shielding films inclined may be included in the aspect of the present disclosure. 
     Due to the side shielding film  116  being inclined, the sound generated from the speaker  170  disposed at the upper side is guided toward the speaker hole  115 . In addition, even if moisture is infiltrated to the rear side of the control panel  110  through the speaker hole  115 , the moisture flows down along the side shielding film  116  that is inclined. 
     The rear shielding film  117  is formed in parallel to the control panel  110  while connecting the two side shielding films  116  to each other. The rear shielding film  117  is configured to block the rear side of the speaker hole  115  while being spaced apart from the speaker hole  115  such that the moisture is blocked from being infiltrated through the speaker hole  115 . 
     The side shielding film  116  and the rear shielding film  117  cover the rear side and the lateral side of the speaker hole  115  while opening the lower side, thereby forming a drain hole  119 . 
     The moisture being infiltrated into the speaker hole  115  is drained through the drain hole  119  after being blocked by the side shielding film  116  and the rear shielding film  117 . 
     The side shielding film  116  and the rear shielding film  117  form the shielding unit  118  at the rear side of the speaker housing  140 . 
     The speaker  170  may be mounted at the rear surface of the speaker housing  140 . On a region of the speaker housing  140  at which the speaker  170  is mounted, a part of the region is open to form the opening  143  such that the sound generated from the speaker  160  passes through the opening  143 . 
     A protecting rib  142  is formed at the center of the opening  143  to protect the speaker  170  after the speaker  170  is mounted. The protecting rib  142  covers a part of the opening  143  to protect the speaker  170  without covering the whole area of the opening  143 , so that the sound generated from the speaker  170  passes through the opening  143 . 
     The guide rib  141  is formed around the opening  143  such that the sound passing through the opening  143  after being generated from the speaker  170  is guided toward the speaker hole  115 . That is, the guide rib  141  is formed such that the sound passing through the opening  143  is fully transmitted to the speaker hole  115  without being spread to other direction. 
     Since the speaker hole  115  is formed at a lower side of the opening  143 , the guide rib  141  is provided in a form opening at a lower side of the opening  143  while covering an upper side, a left side and a right side of the opening  143 . 
     The guide rib  141  is formed to connect to the side shielding film  116  such that the sound being generated from the speaker  170  is guided toward the speaker hole  115 . 
       FIG. 6  is a perspective view illustrating a configuration coupled at a rear of a housing shown on  FIG. 3 . 
     Referring to  FIG. 6 , the housing  120  includes the display housing  130  and the speaker housing  140 . 
     The speaker  170  and the communication module  180  are disposed at the rear of the speaker housing  140 . Meanwhile, the display unit  150  is disposed on the front surface of the display housing  140  and the main board  160  is disposed on the rear surface of the display housing  140 . 
     A plurality of first fixing clips  132  is provided on the rear surface of the display housing  140  to fix the main board  160 . The plurality of first fixing clips  132  supports the edge of the main board  160  such that the main board  160  is fixed to the rear surface of the display housing  140 . 
     A position determining protrusion  135  is formed at a portion of the display housing  140  corresponding to each corner of the main board  160 . The position determining protrusion  135  is configured to restrict each corner of the main board  160  such that the main board  160  is fixed to the rear side of the display housing  140  at a precise position. 
     Although the main board  160  in accordance with an embodiment of the present disclosure is illustrated as being mounted to the display housing  130  by only use of the first fixing clip  132 , the present disclosure is not limited thereto. Having the main board  160  fixed to the display housing  130  by use of an additional fastening member may be included in the aspect of the present disclosure. 
     Since the communication module  180 , the speaker  170 , and the cable  151  of the display unit  150  need to be coupled to the main board  160 , the main board  160  needs to be fixed at a precise position. 
     The cable  151  connected to the display unit  150  extends to the rear of the display housing  130  through the through-hole ( 137  in  FIG. 3 ) and then is connected to a first connector  163  provided on the main board  160 . 
     The main board  160  may be provided at one side thereof with a second connector  161  to which the speaker  170  is connected by cable  175 , and a third connector  162  to which the communication module  180  is connected. 
       FIG. 7  is an enlarged view illustrating a speaker housing shown on  FIG. 6 . 
     Referring to  FIG. 7 , the speaker  170  is disposed at the rear of the speaker housing  140 . 
     A fixing rib  144  protrudes from the rear surface of the speaker housing  140  in a shape corresponding to the external appearance of the speaker  170 . A speaker mounting part  145  is formed at an inner side of the fixing rib  144  such that the speaker  70  is mounted on the speaker mounting part  145 . The fixing rib  144  is provided in a shape corresponding to the shape of the speaker  170 , and the speaker mounting part  145  is provided in a size suitable for the speaker  170  to be mounted thereon. 
     A plurality of fixing clips  146  is formed adjacent to the speaker mounting part  145  of the speaker housing  140 . A fixing protrusion  171  is formed from a lateral side of the speaker  170  in a radial direction from the speaker  170 . 
     As the speaker  170  is mounted on the speaker mounting part  145 , the plurality of second fixing clips  146  supports the fixing protrusion  171 , so that the speaker  170  is fixed to the speaker housing  140 . 
     The opening  143  is formed through the center portion of the speaker mounting part  145  such that the sound generated from the speaker  170  is transmitted through the opening  143 . The protecting rib  142  is formed at the opening  143  to protect the speaker  170 . 
       FIG. 8  is a perspective view illustrating a washing machine in accordance with another aspect of the present disclosure.  FIG. 9  is a perspective view illustrating the configuration of a control panel assembly of the washing machine shown on  FIG. 8 . 
     Referring to  FIGS. 8 and 9 , a washing machine  2  includes a cabinet  10  forming the external appearance of the washing machine  2 , and a control panel assembly  200 . 
     The control panel assembly  200  includes a control panel  210  that forms the external appearance of the control panel assembly  200  while being slantingly mounted on an upper portion of a front surface of the cabinet ( 10  in  FIG. 1 ), a circuit board assembly  220  disposed at a rear of the control panel  210 , a rotary switch  230  disposed in parallel to the circuit board assembly  220  at the rear of the control panel  210 , and a knob  235  connected to the rotary switch  230  while being mounted on a front surface of the control panel  210 . 
     The circuit board assembly  220  includes a printed circuit board  260 , and a circuit board housing  221  on which the printed circuit board  260  is mounted. 
     A plurality of first light emitting units  265  are mounted on the printed circuit board  260  to display a setting state set by a user, and a display device  250  to display the operating status of the washing machine  2 . 
     At the circuit board housing  221 , a plurality of setting switches  266  are disposed at a lower side of the printed circuit board  260  for a user to manipulate the washing machine  2 . 
     At the circuit board housing  221 , a power switch  264  is disposed at one side of the printed circuit board  260  to turn on/off the washing machine  2 . 
     A switch housing  231  forms the external appearance of the rotary switch  230 . A rotary rod  232  is provided at the center of the switch housing  231 . The rotary rod  232  is coupled to the knob  235  so as to generate a plurality of signals in stages while rotating together with the knob  235 . 
     A second light emitting unit  233  is provided around the rotary rod  232  so as to flicker such that the wash course corresponding to the degree of rotation of the knob  235  is indicated while indicating the degree of rotation of the knob  235 . 
     A detergent container accommodating port  212  is provided at one side of the control panel  210  while being penetratively formed through the control panel  210  such that a detergent container  52  is detachable toward the inside the cabinet  10 . 
     A knob mounting part  236  is formed at the center of the control panel  210  such that the knob  235  is mounted on the knob mounting part  236 . The rotary switch  230  is installed at the rear of the knob mounting part  236 . 
     A plurality of buttons  213  is disposed at one side of the control panel  210  to cover the setting switch  266  and the power switch  264  for a user to smoothly press the switches  266  and  264 . 
     A display window  214  is provided at a position of the control panel  210  corresponding to the display device  250  such that an image formed from the display device  250  is displayed to the front of the control panel  210 . 
     A speaker  270  is mounted at a rear of one side of the circuit board housing  221 . 
     A speaker hole  215  is provided at a lower side of a region of the control panel  210 , the region corresponding to the speaker  270 , such that the sound generated from the speaker  270  is transmitted to the front of the control panel  210 . 
     A side shielding film  216  is formed at the rear surface of the control panel  210  while protruding from the both sides of the speaker hole  215  to the rear side of the control panel  210 . The side shielding films  216  is provided in two units thereof, one for each side of the speaker hole  215 . The two side shielding films  216  are inclined to be adjacent to each other while nearing each other from the upper side to the lower side. 
     A rear shielding film  217  is formed to connect the two side shielding films  216  to each other while in parallel to the control panel  210 . 
     At a region of the circuit board housing  221  on which the speaker  270  is mounted, an opening  243  is penetratively formed through a part of the region of the circuit board housing  221 . 
     A protecting rib  242  is formed at the center of the opening  243 . 
     A guide rib  241  is formed around the opening  243  such that the sound generated from the speaker  270  is guided toward the speaker hole  215  after passing through the opening  243 . 
     Since the speaker hole  215  is formed at a lower side of the opening  243 , the guide rib  241  is provided in a form opening at a lower side of the opening  243  while covering a left side and a right side of the opening  243 . 
     The guide rib  241  is formed to be connected to the side shielding film  216  such that the sound generated from the speaker  270  is guided toward the speaker hole  215 . 
     Although a few embodiments of the present disclosure 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 disclosure, the scope of which is defined in the claims and their equivalents.