Patent Publication Number: US-7582841-B2

Title: Control button of drum type washing machine

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
   The present application claims priority to Korean patent application number 10-2006-0131337, filed on Dec. 20, 2006, which is incorporated by reference in its entirety. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a drum type washing machine, and more particularly to a control button of a drum type washing machine that can be retracted inside a control panel after use of the control button or when manipulation thereof is not required. 
   2. Description of the Related Art 
   Generally, a drum type washing machine is constructed such that a washing operation can be performed by lifting and dropping laundry in a cylindrical drum while rotating the drum about a horizontal axis inside a washing tub. The drum type washing machine has merits in that it experiences lower laundry damage resulting from laundry twisting and employs a smaller amount of water for the washing operation, as compared to an agitator type washing machines. 
     FIG. 1  is a perspective view illustrating a conventional drum type washing machine A, which includes a cabinet having a front cover  100 . The washing machine A has a large door  110  coupled to a front central region of the front cover  100 . The door  110  is selectively openable to permit a user to input or output laundry therethrough, and to allow a user to confirm a washing state of the laundry. A detergent drawer  120  is provided that is capable of being drawn out forward at one side of an upper portion of the washing machine to contain detergent and laundering additives such as fabric softener. 
   Additionally, at one side of the detergent drawer  120 , the washing machine A is provided with a plurality of buttons  140  for selecting and controlling functions and operations of the washing machine A, a control button  150  for selecting one of various washing cycles, and a control panel  130  which includes a display device  160  for displaying the washing state of the laundry. 
   A printed circuit board (not shown) is coupled to the rear side of the control panel  130 , and includes a rotary switch (not shown) capable of being rotated through manipulation of the control button  150  and other components. The printed circuit board is an electronic component that is connected to a microcomputer for controlling the operation of the washing machine, and receives input signals relating to the washing cycles or provides signals relating to the washing states. 
     FIG. 2  is a cross-sectional view illustrating a coupled state of the control button and the printed circuit board of the conventional washing machine. The printed circuit board  170  attached to the rear side of the control panel  130  has a rotary switch  180  that is an electronic component for selectively inputting one of the various washing cycles, such as a standard cycle, wool/lingerie cycles, and the like. The control button  150  for manipulating the rotary switch  180  is coupled to one end of the rotary switch  180  outside the control panel  130 . 
   The control button  150  includes a body  152  protruding from the control panel  130 , and a fastening part  154  integral to the rear side of the body  152  and coupled to the rotary switch  180 . 
   Since the body  152  of the control button  150  protrudes from the control panel  130 , however, it is possible to inadvertently change the selected washing cycle through accidental contact with the control button  150 . Moreover, the control button  150  can be damaged in the event where the contact causes a large impact to the control button  150 . 
   Therefore, there is a need to provide an improved drum type washing machine that overcomes such problems. 
   SUMMARY OF THE INVENTION 
   The present invention is conceived to solve the problems of the conventional techniques as described above, and an aspect of the present invention is to provide a control button of a drum type washing machine that can be retracted inside a control panel after use of the control button or when manipulation thereof is not required. 
   In accordance with one aspect of the present invention, this and other objects can be accomplished by the provision of a control button of a control panel for manipulating a rotary switch, the control button comprising: a button securing part, including a securing body having a fitting hole formed at a center of the securing body, a securing portion extending from one side of the securing body and having a rack formed on an outer surface of the securing portion, and a coupling hole formed inside the securing portion so as to be in communication with the fitting hole, the coupling hole being coupled to the rotary switch; a button operating part, including an operating portion open at one end and having an operating trough and a pinion corresponding to the rack disposed inside the operating portion, a guide member disposed at one side of the operating portion, and an operating body integral to one end of the guide member and to an opposed end of the operating portion; an elastic member having one end mounted between the operating body and the operating portion, and the other end mounted on the button securing part; and a cylindrical button adjusting part provided on the control panel and having the operating body press-fitted into the button adjusting part. 
   Preferably, the guide member comprises: a guide protruding piece formed at one side of an outer peripheral surface of the operating portion and having a guide-piece guiding portion defined therein; a guide-piece controlling protrusion formed on the guide-piece guiding portion which divides the guide-piece guiding portion, the guide-piece controlling protrusion including a guide groove which faces the operating body, the guide groove having a V-shape such that the guide groove comprises a first slope and a second slope; and a guide-piece having a moving end and a fixed end, the moving end capable of moving along the guide-piece guiding portion to control operation of the button operating part, and the fixed end secured to the button securing part. 
   More preferably, the guide-piece controlling protrusion has a corner facing the guide-piece and biased to one side of an imaginary straight line extending along a longitudinal axis of the guide-piece. 
   More preferably, the guide member comprises a secondary guide-piece controlling protrusion formed on a surface of the operating portion so as to contact the operating body while facing the guide groove. 
   More preferably, the secondary guide-piece controlling protrusion has a corner facing the guide groove and biased to one side from an imaginary straight line extending from a center of the guide groove. 
   More preferably, the first slope of the guide groove is longer than the second slope. 
   Preferably, the button securing part, the button operating part, and the button adjusting part are made from a metallic material. 
   Preferably, the button securing part, the button operating part, and the button adjusting part are made from a synthetic resin. 
   Preferably, the rack cooperatively engages the pinion such that: the securing portion is coupled to the operating portion; and the speed of the relative motion between the securing portion and the operating portion is governed. 
   Preferably, the control panel forms a portion of a cabinet of a washing machine such that the rotary switch permits selection of a washing cycle from a plurality of washing cycles. 
   In accordance with another aspect of the present invention, a control button which manipulates a rotary switch, the rotary switch mounted to a printed circuit board disposed within a control panel, the control button comprising: a button securing part mounted on the control button to the printed circuit board; a button operating part mounted on the button securing part and configured to move relative to the button securing part in a direction normal to the printed circuit board between a retracted position and an extended position; an elastic member disposed between the operating body and the operating portion arranged to bias the button operating part to the extended position; and a cylindrical button adjusting part provided on the control panel, the button adjusting part comprising an annular wall and a closed end which define a button adjusting part interior space, wherein the button operating part is press-fit into the button adjusting part interior space, and the annular wall resides within an opening formed in the control panel such that the closed end is substantially flush with a surface of the control panel when the control button is in the retracted position, and the closed end is positioned outwardly of the surface of the control panel when the control button is in the extended position. 
   Preferably, the button securing part comprises an elongate guide piece, the button operating part comprises a guiding portion, the guiding portion comprising a guide-piece controlling protrusion disposed at one end of the guiding portion, the guide piece moves within the guiding portion, and the button operating part is maintained in the retracted position relative to the button securing part through engagement of the guide piece with the guide-piece controlling protrusion. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects, features and advantages of the present invention will become apparent from the following description of exemplary embodiments given in conjunction with the accompanying drawings, in which: 
       FIG. 1  is a schematic perspective view of a conventional drum type washing machine; 
       FIG. 2  is a cross-sectional view illustrating a coupled state of a control button and a printed circuit board of the conventional washing machine of  FIG. 1 ; 
       FIG. 3  is an exploded perspective view of a control button of a drum type washing machine according to one embodiment of the present invention; 
       FIG. 4  is a cross-sectional view illustrating a coupled state of the control button and a printed circuit board of the washing machine according to the embodiment of the present invention; and 
       FIG. 5  is a front view of the control button illustrating the control button in an extended position according to the embodiment of the present invention; 
       FIG. 6  is a front view of the control button illustrating the control button in a retracted position according to the embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. For descriptive convenience, the present invention will be described based on a control button of a drum type washing machine. The drawings may be exaggerated in thickness of lines or size of components for the purpose of descriptive convenience and clarity only. 
   Furthermore, terms used herein should be defined in consideration of functions of components of the present invention and thus can be changed according to the custom or intention of users or operators. Therefore, definition of such terms should be determined according to overall disclosures set forth herein. 
   Referring to  FIGS. 3 to 6 , the control button  10  of the drum type washing machine comprises a button securing part  20 , a button operating part  30 , an elastic member  40 , and a button adjusting part  50 . 
   The button securing part  20  is to be coupled to a rotary switch  60  disposed on a printed circuit board  80 , and generally comprises a securing body  21 , a securing portion  22  and a coupling hole  26 . 
   The securing body  21  has a circular shape, and fitting hole  21 A is formed at the center thereof. The securing portion  22  extends from one side of the securing body  21  and has a rack  23  formed on an outer surface of the securing portion  22 . 
   The securing portion  22  has a plurality of securing hooks  25  formed on an outer peripheral surface of one end of the securing portion  22 , and, the rack  23  is engaged with a pinion  38  described below and serves to reduce the speed of the control button  10  when the control button  10  is inserted into or protruded from a control panel  90 . 
   The coupling hole  26  is in communication with the fitting hole  21 A inside the securing portion  22  and is coupled to the rotary switch  60 . 
   The button operating part  30  is to be coupled to one side of the button securing part  20 , and comprises an operating portion  31 , a guide member  32  and an operating body  39 . 
   The operating portion  31  has an operating trough  31 A formed therein, and a pinion  38  mounted within the operating trough  31 A so as to be engaged with the rack  23 , whereby the securing portion  22  of the button securing part  20  is coupled to the operating portion  31 . Further, the operating portion  31  is open at one end thereof. Specifically, the open end of the operating portion  31  faces the button securing part  20 . 
   The guide member  32  is formed along one side of the operating portion  31 , and the operating body  39  is integral to one end of the guide member  32 , and to an end of the operating portion  31  that is opposed to the open end. 
   Latch hooks  31 B corresponding to the securing hooks  25  are formed on an inner peripheral surface at an inlet side of the operating trough  31 A of the operating portion  31 . The latch hooks  31 B cooperatively engage the securing hooks  25  to prevent separation of the button operating part  30  from the button securing part  20 . 
   Specifically, the guide member  32  generally comprises a guide protruding piece  33 , a guide-piece controlling protrusion  35 , a secondary guide-piece controlling protrusion  35 A, and a guide piece  37 . The guide piece  37  is an elongate, generally U-shaped member having a fixed end  37 A and a movable end  37 B. 
   The guide protruding piece  33  extends integrally on one side of an outer peripheral surface of the operating portion  31  in the longitudinal direction and has a guide-piece guiding portion  34  defined therein. 
   The guide-piece controlling protrusion  35  is formed on the guide-piece guiding portion  34  to divide the guide-piece guiding portion  34  to a first guide section  34 A and a second guide section  34 B. Here, the first guide section  34 A indicates a first side (for example, the right side) of the guide-piece guiding portion  34  (see  FIG. 5 ) and constitutes a passage along which the control button  10  moves when being inserted into the control panel  90 . The second guide section  34 B indicates a second side (for example, the left side) of the guide-piece guiding portion  34  and constitutes a passage along which the control button  10  moves when being extended from within the control panel  90 . 
   Since the guide-piece controlling protrusion  35  has a leading corner located at one side (for example, a left side) of an imaginary straight line extending along a longitudinal axis of the guide piece  37 , the movable end  37 B of the guide piece  37  is guided toward the first guide section  34 A by the leading corner of the guide-piece controlling protrusion  35  when the button adjusting part  50  is inserted into the control panel  90 . 
   Further, the guide-piece controlling protrusion  35  is formed with a V-shaped guide groove  36  that faces the operating body  39  and is divided into a first slope  36 A and a second slope  36 B. Here, the first slope  36 A indicates a right side of the guide groove  36  (see  FIG. 5 ). The second slope  36 B indicates a left side of the guide groove  36 . When guided to the first guide section  34 A, the movable end  37 B is guided along the first slope  36 A and seated on the guide groove  36 , thereby completing insertion of control button  10  into the control panel  90 . 
   Here, the first slope  36 A of the guide groove  36  is longer than the second slope  36 B to allow the movable end  37 B of the guide piece  37  located on the guide groove  36  to be easily released from the guide groove  36  to permit operation of the button operating part  30  when using the washing machine. 
   The secondary guide-piece controlling protrusion  35 A is formed on one side of the operating portion  31  contacting the operating body  39  and faces the guide groove  36  to allow the movable end  37 B to be easily released from the guide groove  36 . In this embodiment, the secondary guide-piece controlling protrusion  35 A has a triangular shape, in which, assuming one side contacting the one side of the operating portion  31  is a base, another side perpendicular to the base is a height side, and the third side is a hypotenuse, a corner where the height side meets the hypotenuse is formed at a location biased to the first slope  36 A side from an imaginary straight line extending from the center of the guide groove  36 . With this configuration, when the button adjusting part  50  is pressed, the movable end  37 B is moved from the guide groove  36  to the secondary guide-piece controlling protrusion  35 A, slides along the hypotenuse of the secondary guide-piece controlling protrusion  35 A to the second guide section  34 B, and is then finally released. 
   The fixed end  37 A of the guide piece  37  is secured to the button securing part  20  such that the movable end  37 B can control the operation of the button operating part  30  while moving along the guide-piece guiding portion  34 , the first guide section  34 A, the second guide section  34 B, and the like. 
   The elastic member  40  has one end mounted between the operating body  39  and the operating portion  31 , and the other end mounted on the securing body  21  of the button securing part  20 . As the button operating part  30  is moved toward the button securing part  20  after insertion of the control button  10 , the elastic member  40  becomes compressed. When the movable end  37 B of the guide piece  37  is released from the guide groove  36  by pressing the button adjusting part  50 , the button operating part  30  is moved in a direction where restoration of the compressed elastic member  40  occurs, thereby allowing the control button  10  to extend outward relative to the control panel  90 . 
   The button adjusting part  50  is provided to the control panel  90 , and has a cylindrical shape, of which one end  52  is closed and the other end  56  is open. The operating body  39  of the button operating part  30  is press-fitted into the open end  56  of the button adjusting portion  50 . The annular wall portion  54  of the button adjusting part  50  resides within an inserting hole  92  formed in the control panel  90  such that the closed end  52  is substantially flush with a surface of the control panel  90  when the control button  10  is in the retracted position, and the closed end  52  is positioned outwardly of the surface of the control panel  90  ( FIG. 4 ) when the control button  10  is in the extended position. 
   The button securing part  20 , button operating part  30  and button adjusting part  50  are made from a metallic material or a synthetic resin 
   Next, an operating principle of the control button of the drum type washing machine according to one embodiment of the invention is described with reference to  FIGS. 4 to 6 . 
   The control button  10  of the drum type washing machine is coupled to the rotary switch  60  disposed on the printed circuit board  80  through the inserting hole  92  of the control panel  90 . Then, when a user rotates the control button  10  toward a mark indicating a certain washing cycle among various washing cycles, the rotary switch  60  will be rotated by the rotation of the control button  10 . The rotary switch  60  is provided for selectively inputting one of the various washing cycles, such as a standard cycle, wool/lingerie cycles, etc., to the printed circuit board  80 , and enables the washing machine to perform the washing cycle selected by the user. 
   Next, principles of insertion and protrusion of the control button are described. 
   When the inserted button adjusting part  50  of the control button  10  is pressed, the button operating part  30  is moved inward by the compressive force to the button adjusting part  50 . Then, the movable end  37 B of the guide piece  37  located in the guide groove  36  is moved to the secondary guide-piece controlling protrusion  35 A, and is guided to the second guide section  34 B along the hypotenuse of the secondary guide-piece controlling protrusion  35 A. 
   When the movable end  37 B is released from the guide groove  36 , the elastic member  40 , which has been compressed between the button operating part  30  and the button securing part  20 , is restored to its original state, and the button operating part  30  moves away from the button securing part  20 . At this time, the movable end  37 B is located at the other end of the guide protruding piece  33  after being moved along the second guide section  34 B and the guide-piece guiding portion  34 , and the button adjusting part  50  protrudes from the control panel  90  (see  FIG. 5 ). 
   The button operating part  30  spaced from the button securing part  20  is not completely separated from button securing part  20  since the latch hooks  31 B of the button operating part  30  are latched to the securing hooks  25  of the button securing part  20 . 
   In this state, the user operates the washing machine to perform a selected washing cycle by rotating the control button  10  toward the selected washing cycle. 
   Further, after using the control button  10 , the user pushes the control button  10  again to make the button adjusting part  50  retract into the control panel  90 . 
   Specifically, when pushing the button adjusting part  50  of the control button  10  while it is protruding from the control panel  90 , the button operating part  30  is moved toward the button securing part  20  by the compressive pushing force applied to the button adjusting part  50 . Here, since the leading corner of the guide-piece controlling protrusion  35  is biased to a left side, the movable end  37 B of the guide piece  37  is moved to the first guide section  34 A from the guide-piece guiding portion  34 . In this state, when further pressing the button adjusting part  50 , the movable end  37 B is guided to the first slope  36 A of the guide groove  36  after moving along the first guide section  34 A, and when the button adjusting part  50  is released, the movable end  37 B is located and stopped at the center of the guide groove  36 . That is, movable end  37 B is located and stopped between the first slope  36 A and the second slope  36 B by the restoration force of the elastic member  40 , after moving along the first slope  36 A of the guide-piece controlling protrusion  35 . 
   As a result, the separation between the button securing part  20  and the button operating part  30  is narrowed, and the button adjusting part  50  is retracted into the control panel  90  through the inserting hole  92  of the control panel  90 , so that the button adjusting part  50  does not protrude from the control panel  90  (see  FIG. 6 ). 
   Further, the configurations of the rack  23  formed on the button securing part  20  and the pinion  38  formed on the button operating part  30  corresponding to the rack  23  enable retraction and extension of the control button  10  with respect to the control panel to be performed more smoothly. With cooperation of the rack  23  and the pinion  38 , it is possible to prevent reduction in coupling force between the button coupling part  20  and the button operating part  30 , which can be caused by an accidental retraction or extension of the control button  10 , while improving operating sensations experienced by the user when the control button  10  is inserted into or protruded from the control panel  90 . 
   As apparent from the above description, the control button of the drum type washing machine according to the present invention can be retracted inside the control panel after use of the control button or when manipulation thereof is not required, thereby preventing unwanted manipulation of the control button, which can occur during use of the washing machine. With this construction, it is possible to prevent in advance an unintended change in a washing cycle. Furthermore, since the control button can be received inside the control panel, it is possible to prevent damage of the control button due to an accidental contact with external things. 
   Although the present invention has been described with reference to the embodiments and the accompanying drawings, these embodiments are provided for the illustrative purpose, and it will be apparent to those skilled in the art that various modifications and equivalent embodiments can be made from these embodiment disclosed herein. 
   Furthermore, although the present invention has been described based on the control button of the drum type washing machine as one example, the control button of the present invention can be applied to any kind of electronic appliance to prevent unwanted manipulation of the control button. Therefore, the scope of the present invention should be limited only by the accompanying claims.