Abstract:
An air cleaner having a manipulator is disclosed. The manipulator ( 200 ) includes a rotary manipulation unit ( 300 ), which is provided so as to be movable between a first position, at which the rotary manipulation unit is retracted into the air cleaner, and a second position, to which the rotary manipulation unit is extracted from the air cleaner to enable a user to manipulate the rotary manipulation unit. The manipulator further includes a lift unit ( 400 ), which is installed in the air cleaner to move the rotary manipulation unit between the first position and the second position. In the present invention, the manipulator can control several functions of the air cleaner obviating the need for having several control buttons, thus being more convenient for a user. Furthermore, the present invention can prevent water from permeating a PCB mounted in the rotary manipulation unit, thus preventing malfunction of the encoder unit.

Description:
This application is a U.S. National Application of PCT International Application No. PCT/KR2008/004580, filed Aug. 7, 2008. 
     TECHNICAL FIELD 
     The present invention relates, in general, to air cleaners and, more particularly, to an air cleaner which has a rotary manipulator, which is retractably extracted from the outer surface of the air cleaner and is able to prevent water from being undesirably drawn therethrough and into the air cleaner. 
     BACKGROUND OF THE INVENTION 
     As is well known to those skilled in the art, air cleaners are apparatuses which purify polluted air to change it into clean air. Typically, an air cleaner is installed in a room having a predetermined volume and functions to remove pollution substances and harmful bacteria from the air in the room and thus provide clean air. 
     According to the purification method used, such air cleaners are classified into filter type air cleaners, electrostatic precipitation air cleaners and anion generating air cleaners. The filter type air cleaners typically include several filters, such as a free filter (or a medium filter) for removing large particles, a HEPA filter for removing fine particles, and an active carbon filter for removing noxious gas and odor. Recently, in particular, water filters which remove pollution, such as dust or particulates, using the absorptive force of water, are also widely used. The electrostatic precipitation air cleaners collect dust and remove odors using a high voltage. The electrostatic precipitation air cleaners can effectively remove fine particles of dust as well as large particles of dust, thus creating a superior air cleaning effect. However, after a predetermined amount of dust is collected, dust may become undesirably separated from a dust collection plate. Therefore, the dust collection plate must be frequently cleaned and maintained. The anion generating air cleaners make use of the property of anions to bond noxious substances floating in the air. 
     Meanwhile, according to the installed orientation, air cleaners are classified into stand type air cleaners and table type air cleaners. The stand type air cleaners are placed upright on the ground. The table type air cleaners are horizontally placed on the ground such that covers disposed on the upper surfaces of the air cleaners can be used as tables. 
       FIG. 1  is a view showing the external shape of a typical air cleaner. As shown in  FIG. 1 , the conventional air cleaner  1  includes a casing  2 , which has a predetermined shape (typically, a rectangular parallelepiped shape). An inlet port  3  and an outlet port  4  are formed in the casing  2 . 
     Furthermore, a fan (not shown) is typically installed in the casing  2  of the air cleaner  1 . Air in a room is drawn into the casing  2  through the inlet port  3  by the operation of the fan (not shown). Thereafter, noxious substances are removed from air using one of the above-mentioned air cleaning methods. Cleaned air is subsequently discharged from the air cleaner  1  through the outlet port  4 . 
     A manipulator  5  is provided on the casing  2  of the air cleaner  1  to manipulate and control the operation of the air cleaner  1 . 
     In detail, the operations of turning on/off the air cleaner  1 , cleaning intensity, cleaning operation duration, an air discharge direction, or a cleaning mode such as a sandy dust removing mode, a dehumidifying mode, a humidifying mode, are controlled using the manipulator  5 . 
     However, the manipulator  5  of the conventional air cleaner  1  includes control buttons  6 . To control the several functions of the air cleaner  1 , the several control buttons  6  corresponding to the number of functions of the air cleaner  1  is required. 
     In particular, recently, as well as having the basic air cleaning function, the air cleaners are manufactured with a tendency to be able to conduct various air cleaning functions depending on conditions in rooms. Therefore, in response to this, the number of control buttons  6  must concomitantly be increased. In this case, the manipulator  5  occupies a relatively large area of the outer surface of the air cleaner  1 , thus deteriorating the external appearance of the air cleaner  1 . 
     In addition, when it is desired for a user to control the functions of the air cleaner  1 , the user must check all control buttons  6  corresponding to the respective functions and thereafter push the desired button or buttons. 
     Moreover, with regard to an air cleaner which has an encoder unit and is convertible between a table type and a stand type, in the case where the air cleaner is used in the table type manner, the encoder unit may inconvenience the user, because the encoder unit protrudes from the outer surface of the air cleaner to allow the user to hold and rotate the encoder unit. As well, there is a problem in that water may enter the encoder unit, with the result that a printed circuit board (hereinafter, referred to in common as ‘PCB’) of the encoder unit is damaged by water. That is, in the case where the air cleaner is used in the table type manner, the cover provided on the upper surface of the air cleaner forms the upper surface of the table. Because the encoder unit is typically provided in the cover that forms the upper surface of the table, water may permeate the encoder unit. As a result, the PCB of the encoder unit may be damaged. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an aspect of the present invention is to provide an air cleaner which has a rotary manipulator in place of the conventional button type manipulators, thus improving the external appearance of the air cleaner, and facilitating the manipulation of the manipulator, wherein water is prevented from being drawn into the air cleaner through the rotary manipulator by virtue of its construction. 
     In an aspect, the present invention provides an air cleaner having a manipulator, wherein the manipulator includes: a rotary manipulation unit provided so as to be movable between a first position, at which the rotary manipulation unit is retracted into a casing of the air cleaner, and a second position, at which the rotary manipulation unit is extracted from the casing of the air cleaner to enable a user to manipulate the rotary manipulation unit, wherein when the rotary manipulation unit is disposed at the second position, the rotary manipulation unit is allowed to be rotated by the manipulation of the user to control operation of the air cleaner; and a lift unit supportably installed in the air cleaner to move the rotary manipulation unit between the first position and the second position. 
     The rotary manipulation unit may include: a handle, having a knob and an extension part extending from a lower end of the knob in a circumferential direction; an upper cover for supporting the extension part of the handle to prevent the handle from being removed from a correct position thereof; a lower cover for covering a lower surface of the upper cover; and a control signal generator mounted to the lower cover to generate various control signals corresponding to the rotation of the handle for controlling the air cleaner. 
     The control signal generator may include: an encoder mounted to a PCB and connected to a rotating center of the handle to generate different control signals depending on angles at which the handle is rotated to; and at least one luminous unit to generate various colors of light. 
     The extension part of the handle may include: a first extension extending outwards from an outer surface of the knob in a horizontal direction; and a second extension extending from an outer edge of the first extension in a vertical direction, wherein the second extension may be inserted between the upper cover and an annular protrusion part, which protrudes from a perimeter of the lower cover in a vertical direction. 
     The lower cover may include: a first support part, on which the control signal generator is seated; the annular protrusion part protruding upright from an outer edge of the first support part; a second support part extending outwards from an outer lower end of the annular protrusion part on a level plane with the first support part; and a third support part extending upright from an outer edge of the second support part, wherein the second extension of the extension part and an outer edge of the upper cover may be inserted between the annular protrusion part and the third support part and are seated onto the second support part. 
     Furthermore, a drain hole for draining water may be formed through the second support part. 
     The knob of the handle may include a first knob housing extending a predetermined length in a vertical direction, the first knob housing having a cylindrical shape; a second knob housing provided inside the first knob housing at a position spaced apart from the first knob housing by a predetermined distance, the second knob housing vertically extending a length shorter than the length of the first knob housing; and a third knob housing extending downwards from a lower end of the second knob housing towards a center of the control signal generator at a predetermined inclination angle. 
     The third knob housing may reflect light, emitted from the luminous unit provided in the control signal generator, and transmit the light to outside the handle. 
     In addition, a click protrusion may be provided on an inner surface of the upper cover, and a click dial may be formed on an outer surface of the extension part, the click dial engaging with the click protrusion. 
     As well, when the user pushes the rotary manipulation unit in a direction from the second position to the first position, the lift unit may move the rotary manipulation unit from the second position to the first position or from the first position to the second position using a cam mechanism. 
     The lift unit may include: an actuating bar coupled at a first end thereof to the rotary manipulation unit, with a cam guide protruding from one surface of the actuating bar; an elastic member coupled to a second end of the actuating bar; a cam shaft seated into the cam guide, the cam shaft being movable in a lateral direction; and a cam housing having a guide slot for receiving the cam shaft, the cam housing supporting the actuating bar and the elastic member therein, such that the actuating bar is movable upwards or downwards. 
     In another aspect, the present invention provides an air cleaner having a manipulator, wherein the manipulator comprises a rotary manipulation unit for controlling operation of the air cleaner by rotation thereof. 
     The rotary manipulation unit may include: a handle, having a knob and an extension part extending from a lower end of the knob in a circumferential direction; an upper cover for supporting the extension part of the handle to prevent the handle from being removed from a correct position thereof; a lower cover for covering a lower surface of the upper cover; and a control signal generator mounted to the lower cover to generate various control signals corresponding to the rotation of the handle for controlling the air cleaner. 
     The control signal generator may include: an encoder mounted to a PCB and connected to a rotating center of the handle to generate different control signals depending on angles at which the handle is rotated to; and at least one luminous unit to generate various colors of light. 
     The extension part of the handle may include: a first extension extending outwards from an outer surface of the knob in a horizontal direction; and a second extension extending from an outer edge of the first extension in a vertical direction, wherein the second extension may be inserted between the upper cover and an annular protrusion part, which protrudes from a perimeter of the lower cover in a vertical direction. 
     The lower cover may include: a first support part, on which the control signal generator is seated; the annular protrusion part protruding upright from an outer edge of the first support part; a second support part extending outwards from an outer lower end of the annular protrusion part on a level plane with the first support part; and a third support part extending upright from an outer edge of the second support part, wherein the second extension of the extension part and an outer edge of the upper cover may be inserted between the annular protrusion part and the third support part and are seated onto the second support part. 
     Furthermore, a drain hole for draining water may be formed through the second support part. 
     The knob of the handle may include: a first knob housing extending a predetermined length in a vertical direction, the first knob housing having a cylindrical shape; a second knob housing provided inside the first knob housing at a position spaced apart from the first knob housing by a predetermined distance, the second knob housing vertically extending a length shorter than the length of the first knob housing; and a third knob housing extending downwards from a lower end of the second knob housing towards a center of the control signal generator at a predetermined inclination angle. 
     The third knob housing may reflect light, emitted from the luminous unit provided in the control signal generator, and transmit the light to outside the handle. 
     In addition, a click protrusion may be provided on an inner surface of the upper cover, and a click dial may be formed on an outer surface of the extension part, the click dial engaging with the click protrusion. 
     In an air cleaner according to the present invention, a manipulator comprises a rotary encoder unit, which controls several functions of the air cleaner and which obviates the need for having several control buttons, thus being more convenient for a user. 
     Furthermore, because the single rotary manipulator is used in place of several control buttons, the present invention can solve the conventional problem in that the manipulator occupies a large area of the outer surface of the air cleaner. In addition, the present invention is constructed such that the encoder unit can be retracted into the air cleaner. Thus, after the use of the air cleaner (or the setting of the manipulator) is completed, the encoder unit is retracted into the air cleaner, thus improving the external appearance of the air cleaner. 
     Moreover, in the present invention, the structure of a handle of the manipulator and a lower cover is improved, so that water is prevented from permeating a PCB mounted in the lower cover. Thus, the encoder unit is prevented from malfunctioning due to water. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a view showing the external shape of a conventional air cleaner; 
         FIG. 2  is of views showing the external shape of an air cleaner, according to an embodiment of the present invention; 
         FIGS. 3 and 4  are views showing the external shapes of air cleaners according to the embodiment of the present invention; 
         FIG. 5  is a view showing the construction of a manipulator of the air cleaner according to the present invention; 
         FIG. 6  is an exploded perspective view of a rotary manipulation unit of  FIG. 5 ; 
         FIG. 7  is a sectional view of the rotary manipulation unit of  FIG. 6 ; 
         FIG. 8  is a bottom perspective view of the assembled rotary manipulation unit having the elements of  FIG. 7 ; 
         FIG. 9  is a view showing an inner surface of an upper cover of  FIG. 8 ; 
         FIG. 10  is an exploded perspective view of a lift unit according to the embodiment of the present invention; and 
         FIG. 11  is of partial sectional views illustrating the operation principle of the manipulator of the air cleaner according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Hereinafter, an air cleaner according to a preferred embodiment of the present invention will be described in detail with reference to the attached drawings. The embodiment of the present invention pertains to only a manipulator for controlling the operation of the air cleaner, therefore detailed explanation of the method and the principle of air cleaning will be skipped. 
       FIG. 2  is of views showing the external shape of an air cleaner, according to an embodiment of the present invention.  FIGS. 3 and 4  are views showing the external shapes of air cleaners according to the present invention, in which  FIG. 3  illustrates a stand type air cleaner, and  FIG. 4  illustrates a table type air cleaner. 
     As shown in  FIGS. 2 through 4 , the air cleaner  100  has an inlet port  102 , through which air is drawn into the air cleaner  100 , and an outlet port  103 , through which purified air is discharged to the outside of the air cleaner  100 . 
     The inlet port  102  is formed in the front surface of the air cleaner  100 , and the outlet port  103  is formed in the upper surface of the air cleaner  100 . However, the location of the inlet port  102  or the outlet port  103  is not limited to the above-mentioned positions. According to the intended purposes, for example, according to whether the air cleaner  100  is a stand type or a table type, the location of the inlet port  102  or the outlet port  103  may be varied. 
     The air cleaner  100  includes a manipulator  200 . It is preferable that the manipulator  200  be an encoder unit, which is rotatable relative to the air cleaner  100  and is retractably extracted from the air cleaner  100 . 
     The manipulator  200  enables a user to control the operation of the air cleaner  100  according to his/her the desired intensions. Preferably, the manipulator  200  has a rotatable structure, such that the operation and functions of the air cleaner  100  are controlled depending on the rotation of the manipulator  200 . 
     Here, the manipulator  200  can be set such that various operation and functions of the air cleaner  100  are controlled by the manipulator  200 . For example, the operation of turning on/off the air cleaner  100 , cleaning intensity, cleaning duration, air discharge direction, or a cleaning mode such as a sandy dust removing mode, a dehumidifying mode, a humidifying mode, may be controlled by the manipulator  200 . 
     In this specification, the term “controlling the operation of the air cleaner” means that various operations and functions of the air cleaner are controlled. 
     Furthermore, the manipulator  200  is constructed such that it can be extracted from the outer surface of the air cleaner  100  so as to be retractable back into the air cleaner  100 . 
     In detail, under normal conditions, the manipulator  200  is in a state of being disposed inside a casing  101  of the air cleaner  100 . In this state, when the user pushes the manipulator  200  once to control the operation and functions of the air cleaner  100 , which has been in the retracted state, the manipulator  200  is extracted from the casing  101  of the air cleaner  100  to a predetermined distance, thus entering a state in which the user can rotate the manipulator  200  to control the air cleaner  100 . When the user again pushes the manipulator  200 , which has been extracted from the casing  101  of the air cleaner  100 , the manipulator  200  is returned to its original retracted state. 
     Here, the term “retraction of the manipulator  200  into the casing  101  of the air cleaner  100 ” means that the manipulator  200  is inserted into the surface of the casing  101  to a predetermined depth such that one surface of the manipulator  200  is flush with the outer surface of the casing  101 . However, the present invention is not limited to this. 
       FIG. 5  is a view showing the construction of the manipulator according to the present invention.  FIG. 6  is an exploded perspective view of a rotary manipulation unit of  FIG. 5 .  FIG. 7  is a sectional view of the rotary manipulation unit of  FIG. 6 .  FIG. 8  is a bottom perspective view of the assembled rotary manipulation unit having the elements of  FIG. 7 .  FIG. 9  is a view showing an inner surface of an upper cover of  FIG. 8 . 
     The manipulator  200  will be explained in more detail with reference to  FIGS. 5 through 9 . 
     As shown in  FIG. 5 , the manipulator  200  includes the rotary manipulation unit  300  and a lift unit  400 . 
     The rotary manipulation unit  300  serves to control the operation of the air cleaner ( 100 , refer to  FIG. 2 ) and has a rotatable structure. The rotary manipulation unit  300  is constructed such that it is extracted from the casing ( 101 , refer to  FIG. 2 ) of the air cleaner  100  so as to be retractable into the casing  101 . 
     In other words, the rotary manipulation unit  300  is moved between a first position, at which the rotary manipulation unit  300  is in a state of being retracted into the casing  101  of the air cleaner  100 , and a second position, at which the rotary manipulation unit  300  is in a state of being extracted from the casing  101  to allow the user to manipulate the rotary manipulation unit  300 . Preferably, the first position to which the rotary manipulation unit  300  is retracted into the casing  101  of the air cleaner  100  is a position such that an upper surface of a knob  311  of the rotary manipulation unit  300  is flush with the outer surface of the casing  101  of the air cleaner  100 . Furthermore, it is preferable that the second position be a position at which the upper surface of the knob  311  is protruded from (or is exposed from) the outer surface of the casing  101  of the air cleaner  100  by a predetermined distance to allow the user to hold the rotary manipulation unit  300  and rotate it. 
     The lift unit  400  includes a mounting plate  403  and is supported in the air cleaner  100  by fastening the mounting plate  403  to the inner surface of the casing ( 101 , refer to  FIGS. 3 ,  4  and  11 ). An actuating bar  401  is provided in a housing  402  of the lift unit  400  so as to be movable upwards or downwards. The actuating bar  401  is coupled to the rotary manipulation unit  300 , thus moving the rotary manipulation unit  300  between the first position and the second position. 
     As stated above, the manipulator  200  of the present invention functions to control the air cleaner  100  and has the rotatable structure. Furthermore, the manipulator  200  is extracted into the casing  101  of the air cleaner  100  so as to be retractable into the casing  101 . 
     Referring to  FIGS. 5 through 9 , the rotary manipulation unit  300  of the manipulator  200  which conducts the above-mentioned functions and operation includes a handle  310 , which enables the user to hold and rotate it. The handle  310  includes the knob  311 , which has a cylindrical shape, and an extension part  312 , which extends from the circumferential outer surface of the lower end of the knob  311  in a circumferential direction. The rotary manipulation unit  300  further includes an upper cover  320 , into which the extension part  312  is inserted to be prevented from being undesirably removed from the upper cover  320 , a lower cover  340  which covers the lower end of the upper cover, and a control signal generator  330  which is mounted to the lower cover  340 . The control signal generator  330  generates various control signals for controlling the air cleaner depending on the rotation of the handle  310  and transmits the signals to a control unit (not shown) of the air cleaner. 
     It is preferable that the knob  311  of the handle  310  have a cylindrical shape and thus ensure convenience of manipulation. However, in consideration of improvement in the external appearance of the air cleaner  100 , the knob  311  may have a polygonal cross-section. The knob  311  includes a first knob housing  311   a , which vertically extends a predetermined length, and a second knob housing  311   b , which is provided inside the first knob housing  311   a  at a position spaced apart from the first knob housing  311   a  by a predetermined distance. The second knob housing  311   b  vertically extends a length shorter than that of the first knob housing  311   a . The knob  311  further includes a third knob housing  311   c , which extends downwards from the lower end of the second knob housing  311   b  towards the center of the control signal generator  330  at a predetermined inclination angle. The extension part  312  of the handle  310  includes a first extension  312   a , which horizontally extends outwards from the outer surface of the first knob housing  311   a , and a second extension  312   b , which vertically extends from the outer edge of the first extension  312   a.    
     The upper cover  320  has a shape appropriate to cover the extension part  312  of the handle. The upper cover  320  is coupled to the lower cover  340 . The upper cover  320  includes a horizontal part  321 , which horizontally extends, and a vertical part  322 , which is bent from the edge of the horizontal part  321  in the vertical direction. An insert hole  324  is formed through the central portion of the horizontal part  321 . The knob  311  passes through the insert hole  324 . 
     The control signal generator  330  includes an encoder  332 , which is mounted to a PCB  331 , and at least one luminous unit, which emits various colors of light, and is preferably a light emitting diode  333  (hereinafter, referred to as ‘LED’). Of course, another type of light emitting unit may be used as the luminous unit. 
     The encoder  332  functions to transmit input signals, generated depending to the rotation of the handle, to the PCB  331 , thus generating control signals. The encoder  332  is connected at the lower end thereof to the PCB  331 . The upper end of the encoder  332  has a cylindrical rotating shaft structure and thus is coupled to the rotational center of the handle  310 . The control signal generator  330  generates predetermined control signals depending on an angle, at which the handle is rotated, and thus controls the operation of the air cleaner  100 . In this embodiment, several LEDs  333  are provided on the PCB  331  to indicate the state of operation of the air cleaner  100 . Therefore, when various control signals are input depending on the rotation of the handle, the PCB  331  operates the LED or LEDs  333  corresponding to the input control signals such that the LED or LEDs  333  emit light. Here, the LEDs  333  have different colors, so that the control signals can be distinguished. 
     The control signal generator  330  is mounted to the central portion of the lower cover  340 . The lower cover  340  is coupled to the upper cover  320 . The handle  310  and the control signal generator  330  are supported by the lower cover  340  and the upper cover  320 , which are coupled to each other. 
     Three characteristics of the manipulator  200  according to the present invention having the above-mentioned construction will now be discussed. 
     A first characteristic of the manipulator  200  according to the present invention is that even if the air cleaner is placed in the horizontal direction but not placed in the vertical direction, that is, even if the manipulator  200  is oriented in the horizontal direction, the PCB can be prevented from being damaged by water seepage. That is, the manipulator  200  is characterized in that the PCB  331  can be insulated from the outside by the extension part  312  of the handle  310  and the lower cover  340 . 
     To achieve the above-mentioned purpose, the extension part  312  has the first extension  312   a , which horizontally extends outwards from the outer surface of the first knob housing  311   a  of the handle, and the second extension  312   b , which vertically extends from the outer edge of the first extension  312   a.    
     Furthermore, the lower cover  340  includes a first support part  341 , onto which the control signal generator  330  is seated, and an annular protrusion part  342 , which protrudes upright from the outer edge of the first support part  341 . The lower cover  340  further includes a second support part  343 , which extends outwards from the outer lower end of the annular protrusion part  342  on a level plane with the first support part  341 , and a third support part  344 , which extends upright from the outer edge of the second support part  343 . The second extension  321   b  of the extension part and the vertical part  322  of the upper cover are inserted between the annular protrusion part  342  and the third support part  344  and are thus disposed on the second support part  343 . In addition, a drain hole  345  is formed through the second support part  343 . Thus, water, which flows on the outer surfaces of the first knob housing  311   a , the first extension  312   a  and the second extension  312   b , is discharged to the outside the manipulator. 
     A second characteristic of the manipulator  200  according to the present invention is that light generated from the LEDs of the control signal generator  330  is emitted to the outside through the handle  310 , allowing for improvements in the external appearance of the air cleaner and indicating the state of operation of the air cleaner. 
     To achieve the above purpose, the third knob housing  311   c , which is provided inside the handle  310 , is inclined downwards towards the center or the control signal generator  330 , as stated above. 
     In detail, the control signal generator  330  is placed below the third knob housing  311   c.  Light emitted from the LEDs  333  of the control signal generator  330  is reflected by the third knob housing  311   c  and is thus dispersed towards the entire area of the outer surface of the handle. The dispersed light is transmitted to the outside of the handle through various light transmission paths. That is, as shown in  FIG. 7 , light may be emitted to outside the handle via space between the first knob housing  311   a  and the second knob housing  311   b . Some light may be emitted to outside the handle through other light transmission space. 
     In further detail, the third knob housing  311   c  functions to disperse light in various directions emitted from the LEDs. Furthermore, it is preferable that the first through third knob housings and the other elements provided in the handle be coated with material having relatively high reflectability. With regard to the handle, a portion, which connects the first knob housing  311   a  and the second knob housing  311   b  to each other, or other portions, through which light is transmitted to the outside of the handle, are preferably made of transparent material. 
     A third characteristic of the manipulator  200  according to the present invention is that it is constructed such that the user can feel a clicking vibration when rotating the handle  310 . 
     To achieve this purpose, a click protrusion  323  is provided on the inner surface of the horizontal part  321  of the upper cover  320 . A click dial  312   c , which contacts the click protrusion  323  to provide a clicking vibration, is formed on the outer surface of the first extension  321   a  of the handle. 
     Of course, the encoder  332  itself has a structure for providing a clicking vibration when rotating. However, because the handle  310  has a diameter larger than that of the rotating shaft of the encoder  332 , when the user holds and rotates the handle  310 , the clicking vibration may deteriorate. To prevent this, the present invention has the additional click protrusion  323  and click dial  312   c , thus improving the clicking vibration. 
     Here, the number of graduations on the click dial  321   c  or the interval between graduations can be set depending on the number of kinds of operations or functions of the air cleaner that is indicated by the manipulator  200 . 
     Furthermore, the click protrusion  323  may be provided on the inner surface of the vertical part  322 . In this case, the click dial  312   c  is preferably provided on the outer surface of the second extension  312   b.    
       FIG. 10  is an exploded perspective view of the lift unit according to the embodiment of the present invention.  FIG. 11  is partial sectional view illustrating the operating principle of the manipulator of the air cleaner according to the embodiment of the present invention. 
     The lift unit  400  will be explained with reference to  FIG. 10 . The lift unit  400  includes an actuating bar  401 , a coupling plate  403 , an elastic member  405 , a cam shaft  406  and a cam housing  402 , containing these elements therein. The actuating bar  401  is provided in the cam housing  402  so as to be movable upwards or downwards. Here, the term “upwards or downwards” means a direction, in which the rotary manipulation unit ( 300 , refer to  FIG. 6 ) is extracted from or retracted into the casing of the air cleaner. Therefore, the rotary manipulation unit  300  is coupled to a first end of the actuating bar  401 . The actuating bar  401  is moved in the cam housing  402  using cam mechanism. For this, a cam guide  404  which guides a cam shaft  406  protrudes from one surface of the actuating bar  401 . 
     The elastic member  405  is coupled to a second end of the actuating bar  401 . A typical spring may be used as the elastic member  405 . The elastic member  405  provides elastic force to the rotary manipulation unit  300  such that the rotary manipulation unit  300  is biased to the outside of the casing  101  of the air cleaner  100 . 
     The cam housing  402  contains the actuating bar  401 , the elastic member  405  and the cam shaft  406  therein. A guide slot  407  is formed in one surface of the cam housing  402 , so that the cam shaft  406  is movable in the lateral direction along the guide slot  407 . 
     The operative principle of the manipulator according to the embodiment of the present invention will be explained with reference to  FIGS. 10 and 11 . 
     As shown in  FIG. 11 , when the user pushes the knob  311  of the rotary manipulation unit  300 , the lift unit  400  moves the rotary manipulation unit  300  from the state A to the state B or from the state B to the state A using the cam mechanism. Here, the term “pushing the rotary manipulation unit  300 ” means that the user pushes the rotary manipulation unit  300  downwards once and then releases it, so that a predetermined pressure is applied for a predetermined time to the rotary manipulation unit  300  before being released. 
     In the state A, the rotary manipulation unit  300  is disposed at a first position. The state A indicates a normal condition operating state in which the user does not use the rotary manipulation unit  300 . In that state, the elastic member  405  is in a state of having been compressed by the downward movement of the actuating bar  401 . The cam shaft  406  is in a state of having been seated into an upper depression of the cam guide  404 , so that the actuating bar  401  maintains the state of having been moved downwards. 
     From the state A, when the user pushes the knob  311  of the rotary manipulation unit  300 , downward force is applied to the actuating bar  401  for a predetermined time, so that the actuating bar  401  is further moved downwards by the downward force and thus further compresses the elastic member  405 . At this time, because the cam shaft  406 , which has been seated in the upper depression of the cam guide  404 , is movable only in the lateral direction (due to the guide slot  407 , refer to  FIG. 10 ), the cam shaft  406  is moved to the left by a corresponding protrusion of the cam guide  404 , as the actuating bar  401  is moved downwards. Thereafter, when the downward force is removed, the actuating bar  401  is moved upwards by the elastic force of the elastic member  405 . The cam shaft  406  is moved in the direction {circle around (1)} by the upward movement of the actuating bar  401  and then is seated into a lower depression of the cam guide  404 . Thus, the rotary manipulation unit  300  is extracted outwards from the casing  101  of the air cleaner  100 . As a result, the rotary manipulation unit  300  enters the state B and, in other words, is disposed at the second position to allow the user to hold and rotate the rotary manipulation unit  300 . 
     In the state B, when the user pushes the knob  311  of the rotary manipulation unit  300  downwards again, downward force is applied to the actuating bar  401  for a predetermined time. The actuating bar  401  is moved downwards by the downward force and thus compresses the elastic member  405 . The cam shaft  405 , which has been seated in the lower depression of the cam guide  404 , is moved in the direction {circle around (2)} by a corresponding protrusion of the cam guide  404 , as the actuating bar  401  is moved downwards. Thereafter, when the downward force is removed, the cam shaft  405  is seated into the upper depression of the cam guide  404  and enters into the state A. 
     Although the preferred embodiment of the present invention has been disclosed for illustrative purposes, the present invention is not limited to the embodiment. Furthermore, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Therefore, these modifications, additions and substitutions must be regarded as falling within the bounds of the present invention.