Abstract:
An operation device includes a front panel having an opening for operation, an elastically deformable operation component having an operation button and being attached to the front panel so as to cover the opening in the front panel in watertight condition, an insertion part provided in substantially a central portion of the operation component, a retaining ring attached to the insertion part in watertight condition and having a through-hole in a central portion thereof, and an operation shaft having a knob attached thereto and extending through the through-hole in watertight condition. The operation button of the operation component and the operation shaft operate respective operable parts arranged inside the front panel.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    The present invention contains subject matter related to Japanese Patent Application JP 2006-222035 filed in the Japanese Patent Office on Aug. 16, 2006, the entire contents of which are incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an operation device, and more specifically, to an operation device for performing a predetermined operation with operation components provided on a front panel. 
         [0004]    2. Description of the Related Art 
         [0005]    Japanese Unexamined Utility Model Registration Application Publication No. 61-34141, Japanese Unexamined Utility Model Registration Application Publication No. 4-14862, and Japanese Unexamined Patent Application Publication No. 2003-107570 disclose a structure in which a switch or a controllable electric element is rotatably operated with a knob provided on a watertight panel. An operation section disclosed in these known documents has a watertight structure which is achieved by having a seal ring, such as an O ring, interposed between a shaft having a rotatably operated knob attached thereto and an opening in a casing for holding the knob. When push-button switches or the like are arranged around a rotatable operation component, the watertight structures of these push-button switches are achieved separately of that of the rotatable operation component. 
       SUMMARY OF THE INVENTION 
       [0006]    For example,  FIG. 26  shows a configuration of a known operation section in an operation unit of an audio system mounted on an instrument panel of a small ship. An operation knob  1  is a rotatably operable component and is coupled to a light-guiding component  3  with a screw  2 . By using a light-transparent material for a rubber ring  4  disposed at the base portion of the operation knob  1 , the base portion of the operation knob  1  can be made to emit light. In this operation section, a push button  5  has an independent watertight structure, that is, the watertight structure of the push button  5  is separated from that of the operation knob  1 . Therefore, it is difficult to arrange the push button  5  close to the operation knob  1 . 
         [0007]    The operation knob  1  is made watertight by inserting the operation knob  1  into an opening in a front panel  6  from above, and by hooking it with a hook of the light-guiding component  3 . The watertightness is established between the rubber ring  4  having a light-guiding characteristic and the front panel  6 . Therefore, it is necessary that the rubber ring  4  and the front panel  6  maintain watertight condition, that is, that the rubber ring  4  and the opening of the front panel  6  be concentric. Accordingly, a gap has to be provided between the light-guiding component  3  and a rotatable operation shaft  8  of an encoder  7  constituting a volume-control. With this known structure, it is difficult to give the encoder  7  a push function. In addition, when the operation knob  1  comes off, water penetrates into a board section, making the watertightness unreliable. 
         [0008]    As described above, in the known watertight structure, making the operation knob  1  watertight sometimes disrupts the concentricity of the operation knob  1  and the rotatable operation shaft  8  of the encoder  7 . Therefore, a gap has to be provided between the operation knob  1  and the rotatable operation shaft  8  of the encoder  7 . Further, in the structure in which the operation knob  1  is hooked with the hook, two parts are subject to friction during rotation. This causes deformation due to abrasion with the passage of time or temperature changes, making the watertightness unreliable. Further, when the operation knob  1  comes off, the watertightness is hardly maintained. If a rib is provided on the bottom portion of the push button  5  adjacent to the operation knob  1  to achieve watertightness, it is difficult to make the base portion of the operation knob  1  emit light and to arrange the push button  5  close to the operation knob  1 . 
         [0009]    It is desirable to provide an operation device in which water is prevented from penetrating into the inside and in which a watertight structure of an operation knob, which is rotatably operated, and a watertight structure of a push button are linked with each other. 
         [0010]    It is also desirable to provide a watertight operation device that allows a push button to be arranged closer to an operation knob, which is rotatably operated. 
         [0011]    It is also desirable to provide a watertight operation device that allows for a more compact design than a known system. 
         [0012]    It is also desirable to provide an operation device with greater design flexibility. 
         [0013]    It is also desirable to provide an operation device having a smaller-sized, more effective watertight structure. 
         [0014]    How to achieve such an operation device will become apparent from technical ideas and an embodiment of the present invention described below. 
         [0015]    According to an embodiment of the present invention, there is provided an operation device including a front panel having an opening for operation, an elastically deformable operation component having an operation button and being attached to the front panel so as to cover the opening in the front panel in watertight condition, an insertion part provided in substantially a central portion of the operation component, a retaining ring attached to the insertion part in watertight condition and having a through-hole in a central portion thereof, and an operation shaft inserted through the through-hole in watertight condition. The operation button of the operation component and the operation shaft operate respective operable parts arranged inside the front panel. 
         [0016]    According to this operation device, the watertight structure of the operation shaft having the knob is established by the elastically deformable operation component and the retaining ring. Thus, the watertight structure of the operation shaft and the watertight structure of the operation component having the operation button are linked to each other. This allows a push button to be arranged closer to the knob, which is rotatably operated. Accordingly, design flexibility is improved, and the watertight structure can be made smaller. 
         [0017]    The operation shaft with the knob attached thereto may include a volume-adjusting operation shaft disposed on a circuit board arranged inside the front panel, and the operable part operated with the operation button of the operation component may include a switch disposed on the circuit board. Further, the retaining ring may also function as a light guide body that guides light from a light emitting element arranged on the circuit board so that at least a base portion of the knob attached to the operation shaft emits light. The operation device may further include a pressing ring attached externally to the operation component. In this case, the pressing ring applies pressure to the operation component so as to establish the watertight condition between the operation component and the front panel. Further, a display may be provided on the front panel, the display being located beside a position where the operation component is attached so that the display is arranged next to the operation component. 
         [0018]    According to another embodiment of the present invention, there is provided an operation device for performing a predetermined operation with a knob on a front panel. An elastic component having a push button is attached to the front panel in watertight condition, the elastic component having a central portion to which a retaining ring having a through-hole is attached, the knob having an operation shaft attached thereto, the operation shaft extending through the through-hole with a seal ring interposed therebetween. 
         [0019]    According to this operation device, the seal ring arranged in the through-hole of the retaining ring makes the operation shaft attached with the knob watertight. Further, because the retaining ring is attached to the central portion of the elastic component having the push button, the watertight structure of the elastic component having the push button and the watertight structure of the operation shaft having the knob are linked to each other. Accordingly, the elastic component having the push button can be arranged close to the operation shaft having the knob. 
         [0020]    The elastic component may be pressed against the front panel by a pressing ring to establish the watertight condition between the elastic component and the front panel. Further, the retaining ring may include a pair of retaining rings arranged in a stacking manner at the central portion of the elastic component. A periphery of an opening in the central portion of the elastic component may be squeezed between outer peripheries of the retaining rings to establish watertight condition between the elastic component and the pair of retaining rings. Further, the seal ring interposed between the through-hole and the operation shaft may include an O ring. Further, the operation device may function as an operation section of an audio system mounted on an instrument panel in the front of a cockpit of a ship. 
         [0021]    In a preferable embodiment of the present invention, the watertight mechanism is established by linking the watertight structure of the knob and the watertight structure of the adjoining push button. In addition, a part of the push button, which is ivory-yellow, has a light-transmitting function so that light can be emitted from the base portion of the knob. By making the knob the only component to be rotatably operated, a gap between the knob and the operation shaft of the encoder, which is rotatably operated with the knob, can be eliminated. Even when the knob comes off, watertightness can still be maintained because the knob is located outside of the watertight mechanism. In addition, the knob, whose base portion emits light, and the push button on the outer periphery of the knob can both be made watertight while arranging these components close to each other, thereby achieving greater design flexibility. 
         [0022]    According to the above embodiment, it is possible to arrange the knob and the push button closer to each other, while preventing water from penetrating into an internal mechanism, for example, the circuit board. This allows for a more compact design than a known system, and achieves greater design flexibility. Further, this structure benefits general electronic apparatuses, because it enables to be produced smaller-sized products having a watertight structure. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is a perspective view of a relevant part of an audio system for a small ship, showing an operation unit thereof in an open state; 
           [0024]      FIG. 2  is a front view of the audio system; 
           [0025]      FIG. 3  is a front view of the audio system, showing the operation unit thereof in an open state; 
           [0026]      FIG. 4  is a side view of the audio system; 
           [0027]      FIG. 5  is a side view of the audio system, showing the operation unit thereof in the open state; 
           [0028]      FIG. 6  is an exploded perspective view of the operation unit; 
           [0029]      FIG. 7  is a perspective view of a chassis; 
           [0030]      FIG. 8  is a front view of the chassis; 
           [0031]      FIG. 9  is a horizontal sectional view of the chassis; 
           [0032]      FIG. 10  is a perspective view of a front cover; 
           [0033]      FIG. 11  is a front view of the front cover; 
           [0034]      FIG. 12  is a horizontal sectional view of the front cover; 
           [0035]      FIG. 13  is a perspective view of a pressing ring; 
           [0036]      FIG. 14  is a front view of the pressing ring; 
           [0037]      FIG. 15  is a bottom view of the pressing ring; 
           [0038]      FIG. 16  is a sectional view of the pressing ring; 
           [0039]      FIG. 17  is a perspective view of an operation component made of rubber; 
           [0040]      FIG. 18  is a front view of the operation component; 
           [0041]      FIG. 19  is a bottom view of the operation component; 
           [0042]      FIG. 20  is a horizontal sectional view of the operation component; 
           [0043]      FIG. 21A  is a perspective view of an operation knob, and  FIG. 21B  is a sectional view of the same; 
           [0044]      FIG. 22A  is a perspective view of an upper retaining ring, and  FIG. 22B  is a vertical sectional view of the same; 
           [0045]      FIG. 23A  is a perspective view of a lower retaining ring, and  FIG. 23B  is a vertical sectional view of the same; 
           [0046]      FIG. 24  is an exploded perspective view showing watertight structures of the operation component and a rotatable operation shaft; 
           [0047]      FIG. 25  is sectional view showing the watertight structures of the operation component and the rotatable operation shaft in the assembled state; and 
           [0048]      FIG. 26  is a vertical sectional view of a relevant part showing a known watertight structure of an operation section of an audio system for a small ship. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0049]    Now, an embodiment of the present invention will be described with reference to the drawings. The present embodiment relates to an operation section of an audio system mounted to an instrument panel that is installed in the front of a cockpit of a small ship. 
         [0050]      FIG. 1  shows an oblong mounting base  16  fixed on an instrument panel  15  in the front of a cockpit of a ship. A compact disc (CD) player  17  is attached behind the mounting base  16  so as to extend through the instrument panel  15  and project from the back side of the instrument panel  15 . The CD player  17  has an oblong slot  18  into which a CD to be played back can be inserted. When a CD is partially inserted into the slot  18 , the CD is automatically loaded into the CD player  17  where the CD is played back. 
         [0051]    A pair of left and right hinges  19  is arranged on the lower portion of the mounting base  16 . An oblong mounting plate  20  made of metal is connected to the mounting base  16  with these hinges  19 . An operation unit  21  is connected to the mounting base  16  with the mounting plate  20 . As shown in  FIGS. 2 to 5 , the operation unit  21  is supported by the hinges  19  in a rotatable fashion.  FIGS. 2 and 4  show the operation unit  21  in a closed state, that is, a state in which the operation unit  21  covers the mounting base  16 .  FIGS. 3 and 5  show a state in which the operation unit  21  has been rotated downward on the hinges  19 . In this state, the slot  18  on the mounting base  16  is exposed to allow insertion and ejection of a CD. The operation unit  21  has a chassis  22  that constitutes a front panel. Referring to  FIG. 6 , a cord gasket  24  is interposed between the chassis  22  and a back plate  23 , thereby achieving a watertight structure between the chassis  22  and the back plate  23 . 
         [0052]      FIG. 6  is an exploded view showing each component of the operation unit  21 . The chassis  22  is arranged in front of the back plate  23  with the cord gasket  24  interposed therebetween. A circuit board  40  is arranged inside the chassis  22  at a position in front of the back plate  23 . A front cover  52  is attached in front of the chassis  22 , thereby holding an operation component  33  and push buttons  36  onto the chassis  22 . 
         [0053]      FIGS. 7 to 9  show the chassis  22  constituting the front panel. The chassis  22  has a circular opening  30  on the left side thereof. The opening  30  has four connectors  31  provided circumferentially at ninety-degree intervals. A ring connector  32 , which is slightly smaller than the circular opening  30 , is disposed within the opening  30  and connected to the chassis  22  with the connectors  31 . The operation component  33  made of rubber is fitted into arch-shaped openings between the connectors  31 . The operation component  33  is shown in  FIGS. 17 to 20 . The chassis  22  has openings  35  into which the push buttons  36  are fitted. 
         [0054]    As shown in  FIG. 6 , the circuit board  40  accommodated within the chassis  22  has switches  41  operated with the push buttons  34  of the operation component  33 , and switches  42  operated with the push buttons  36 . Referring to  FIGS. 24  and  25 , light-emitting diodes  43  are mounted between the switches  41 . An encoder  44  constituting a volume-control is mounted in an area surrounded by the switches  41  and the light-emitting diodes  43 . The encoder  44  has a rotatable operation shaft  45 , which is operated with an operation knob  66  to be described below. Further, as shown in  FIG. 6 , a liquid-crystal display panel  46  is attached to the circuit board  40  on the right side thereof. The liquid-crystal display panel  46  is viewable from the front through a transparent window  47  arranged in front thereof. 
         [0055]    Referring to  FIGS. 10 to 12 , the structure of the front cover  52  arranged in front of the chassis  22  constituting the front panel will be described. The front cover  52  has a pair of left and right circular openings  53  and  54  and push-button insertion holes  55  and  56 . The above-described push buttons  36  shown in  FIG. 6  are fitted into these push-button insertion holes  55  and  56 . 
         [0056]    Referring to  FIGS. 13 to 16 , a pressing ring  60  arranged on the operation component  33  made of rubber on the chassis  22  will be described. The pressing ring  60  has a relatively large circular opening  59  in the central portion thereof, and has four connectors  61  provided circumferentially at ninety-degree intervals. Ends of the connectors  61  are connected by a ring connector  62 , and the inside of the ring connector  62  forms the opening  59 . The push buttons  34  of the operation component  33  are to be located on the outer periphery of the ring connector  62  and between the connectors  61 . Referring to  FIGS. 6 and 25 , a plated decorative ring  85  is fixed on the pressing ring  60 . 
         [0057]      FIGS. 17 to 20  show the operation component  33  made of rubber. The operation component  33  is an ivory-yellow rubber body having four arch-shaped push buttons  34  along the circumference thereof. The operation component  33  has an insertion hole  37  in the central portion thereof. 
         [0058]    Referring to  FIG. 21 , an operation knob  66  will be described. The operation knob  66  is a synthetic resin body, and has a plurality of ribs  67  on the external surface thereof. These ribs  67  prevent fingers from slipping during operation. A cylindrical connector  68  is provided inside the operation knob  66 . A spring  69  is wound around the cylindrical connector  68 . 
         [0059]    Referring to  FIG. 22 , an upper retaining ring  71  to be attached to the central portion of the operation component  33  made of rubber will be described. The upper retaining ring  71  has a flat, disc-like shape with a depressed portion  72  provided therein. An O ring  74  serving as a seal ring is fitted to the inner periphery of an upper shoulder  73  of the depressed portion  72 . 
         [0060]    As shown in  FIG. 23 , a lower retaining ring  75  to be used in combination with the upper retaining ring  71  for sealing the insertion hole  37  of the operation component  33  has a projection  76  that projects upward. 
         [0061]      FIGS. 24 and 25  show a watertight structure of the operation knob  66  for rotatably operating the rotatable operation shaft  45  of the encoder  44  on the circuit board  40 , and a watertight structure of the operation component  33  having push buttons  34  arranged around the operation knob  66 . In order to achieve these watertight structures, the operation component  33  is first attached so as to cover an opening  30  of the chassis  22  constituting the front panel. Then, the upper retaining ring  71  and the lower retaining ring  75  are engaged with the insertion hole  37  of the operation component  33  from above and below, respectively. These upper and lower retaining rings  71  and  75  squeeze and seal the periphery of the insertion hole  37  of the operation component  33 . Then, the operation component  33  engaged with the upper and lower retaining rings  71  and  75  at the central portion thereof is pressed from above by the pressing ring  60 . The rotatable operation shaft  45  of the encoder  44  on the circuit board  40  extends through the central portions of the upper and lower retaining rings  71  and  75 , and is sealed by the O ring  74  fitted to the shoulder  73  of the upper retaining ring  71  so as to be made watertight. The operation knob  66  is attached to the end of the rotatable operation shaft  45  projecting from the upper retaining ring  71 . 
         [0062]    Accordingly, the watertight structure of the outer periphery of the operation component  33  is achieved by close contact between the outer periphery of the operation component  33  and the chassis  22 . In this structure, the pressing ring  60  presses the outer periphery of the operation component  33  against the chassis  22 . The watertight structure at the central portion of the operation component  33  having the insertion hole  37  is achieved with the upper and lower retaining rings  71  and  75 . More specifically, the outer peripheries of these upper and lower retaining rings  71  and  75  squeeze the edge of the insertion hole  37  in the operation component  33  from above and below, respectively. The watertight structure of the rotatable operation shaft  45  of the encoder  44  with the operation knob  66  attached thereto is achieved with the O ring  74 . The O ring  74  is fitted to the shoulder  73  of the upper retaining ring  71 , among the pair of upper and lower retaining rings  71  and  75  attached to the operation component  33 . Thus, the watertight structure of the rotatable operation shaft  45  of the encoder  44  is achieved with the operation component  33  made of rubber. 
         [0063]    As shown in  FIGS. 24 and 25 , the operation knob  66  is fixedly fitted to the rotatable operation shaft  45  of the encoder on the circuit board  40 . The push buttons  34  adjacent to the operation knob  66  are provided in the operation component  33 , which is made of rubber and is elastic, and are arranged in a ring-like fashion around the operation knob  66 . The operation component  33  is provided with a lip  80  having a rib  82  at the bottom side of the outer periphery of the operation component  33 . The operation component  33  is also provided with a lip  83  having a rib  84  at the bottom side of the inner periphery of the operation component  33 . By sandwiching these ribs, the watertight structure for preventing water from penetrating towards the side of the circuit board  40  is established. Specifically, the lip  80  on the outer periphery of the operation component  33  is fitted into a groove  81  in the chassis  22 , and is squeezed between the chassis  22  and the pressing ring  60 . The rib  82  is thus strongly pressed against the groove  81  in the chassis  22 , whereby the watertight structure is attained. The rib  84  on the bottom side of the lip  83  provided on the inner periphery of the operation component  33  is squeezed between the outer peripheries of the upper and lower retaining rings  71  and  75 , and is pressed against the upper surface of the outer periphery of the lower retaining ring  75 . The chassis  22  and the pressing ring  60  are fastened together with screws. The upper and lower retaining rings  71  and  75  are coupled together with screws  77 . The pressing ring  60  and the front cover  52  can be integrated into a single component if the decorative ring  85  is not necessary. 
         [0064]    The rotatable operation shaft  45  of the encoder  44  is made watertight by the O ring  74  sandwiched between the upper and lower retaining rings  71  and  75 . This structure can allow the encoder  44  to have a push function. Further, in this watertight structure, the upper and lower retaining rings  71  and  75  and the push buttons  34  of the operation component  33  are made of a light-transparent material. The use of the light-transparent material can allow the base portion of the operation knob  66  to emit light by guiding light from the light-emitting diodes  43  on the circuit board  40 . In addition, even when the operation knob  66  comes off, the watertightness can still be maintained because the operation knob  66  is located outside of the watertight mechanism. This structure allows for a reduced distance between the operation knob  66  and the push buttons  34 , and greater design flexibility. 
         [0065]    According to the structure of the present embodiment shown in  FIGS. 24 and 25 , the operation knob  66  and the push buttons  34  can be arranged closer to each other, while preventing water from penetrating into the circuit board  40 . This allows for a more compact design than a known system, as well as achieving greater design flexibility. Further, this structure benefits general electronic apparatuses, because it enables to be produced smaller-sized products having a watertight structure. 
         [0066]    Next, an overall operation of the audio system including the CD player  17  having the operation unit  21  with the aforementioned watertight structure will be described. As shown in  FIGS. 1 ,  3 , and  5 , the operation unit  21  is rotated downward on the hinges  19 . Then, a CD is inserted into the CD player  17  through the slot  18  provided on the mounting base  16 , and the CD is played back with the CD player  17 . When playback is to be performed, the operation unit  21  is rotated upward about the hinges  19  so as to be returned to the original state as shown in  FIGS. 2 and 4 . Sound volume, for example, may be adjusted by rotatably operating the operation knob  66  attached to the rotatable operation shaft  45 . Other predetermined operations can be performed by pressing push buttons  36  exposed through the push-button insertion holes  55  in the front cover  52 , namely, by operating the switches  42  on the circuit board  40 . 
         [0067]    After the playback, the operation unit  21  is rotated downward again as shown in  FIGS. 1 ,  3 , and  5 , and the CD is ejected from the slot  18  on the mounting base  16 . Another CD may be inserted through the slot  18  and played back, if desired. 
         [0068]    The embodiment of the present invention has been described referring to the drawings. However, it should be understood by those skilled in the art that various modifications, combinations, sub-combinations, and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof. For example, the specific shape, the design, or the like of the operation unit  21  according to the above embodiment can be variously modified. The present invention can be broadly applied to any operation section in which watertightness is important.