Patent Publication Number: US-2005129394-A1

Title: Cleaning apparatus for camera

Description:
This application is based on Japanese Patent Application No. 2003-417733 filed in Japan on Dec. 16, 2003, the entire content of which is hereby incorporated by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a cleaning apparatus for a camera, and more particularly to a cleaning apparatus for removing dust, dirt, and other fine foreign particles (hereinafter collectively referred to as “dust”) adhering on an imaging surface in an interchangeable lens type camera.  
      2. Description of the Related Art  
      Some imaging apparatuses, such as digital cameras, silver halide film cameras, and video cameras, come equipped with interchangeable lens systems that allow the changing of lenses ranging from wide angle to telephoto according to the purpose of shooting. Here, in particular, in the case of a camera equipped with an imaging device, if dust adheres to the imaging surface of the imaging device, the adhering dust shows up as grainy noise. Since the dust, once made to adhere to the imaging surface, does not easily come off the imaging surface, the grainy noise always appears on images captured thereafter. Further, in the case of an interchangeable lens type camera equipped with an imaging device, the chance of dust entering the camera body and adhering to the imaging surface further increases when changing the lens; accordingly, it has been strongly desired to provide an apparatus that can remove dust in a simple and reliable manner.  
      As an apparatus for removing dust adhering to the imaging surface, the prior art proposes, for example, an apparatus that blows the dust off the imaging surface by blowing an air stream onto it.  
      In this cleaning apparatus, a CCD unit comprising a protective glass, a filter, and an imaging device arranged one behind another in the stated order as seen from the front side is built into a cleaning case. This cleaning case has an air stream entrance at one end and an air stream exit at the other hand, and is fixed in place inside the camera body. Clean air is introduced through the air stream entrance, and is vented through the air stream exit after passing over the surface of the protective glass of the CCD unit. At this time, the dust adhering on the protective glass is removed by being carried to the outside together with the clean air.  
      In the above cleaning apparatus, since an inlet passage and an outlet passage, to be connected to the air stream entrance and the air stream exit, respectively, of the cleaning case, have to be provided in the camera body in order to flow the air into and out of the cleaning case, the apparatus becomes very large in size. Further, the cleaning case is permanently built into the camera body. Therefore, there has been the problem that not only does the available space in the camera body become smaller because the cleaning case occupies the interior space of the camera body, but also the thickness of the camera body increases. There has also been the problem that the weight of the cleaning case adds to the weight of the camera as a whole.  
     SUMMARY OF THE INVENTION  
      A primary object of the present invention is to provide a compact cleaning apparatus for a camera, that is attached only when dust removal is needed and detached when not needed.  
      Another object of the invention is to provide a compact cleaning apparatus for a camera, that is attachable to and detachable from the mount of the camera, just like an interchangeable lens, and that can be attached only when dust removal is needed.  
      The above objects of the invention are achieved by providing a cleaning apparatus attachable to and detachable from an interchangeable lens type camera, and comprising: a mounting portion which engages with a lens mounting portion of the interchangeable lens type camera; and a cleaning mechanism which removes dust adhering on an imaging surface of the camera.  
      The above objects of the invention are also achieved by providing a cleaning apparatus attachable to and detachable from an interchangeable lens type camera, and comprising: a mounting portion which engages with a lens mounting portion of the interchangeable lens type camera; a cleaning mechanism which removes dust adhering on an imaging surface of the camera; and a moving mechanism which moves the cleaning mechanism between a cleaning position, where the cleaning mechanism is positioned close to the imaging surface, and a retracted position, where the cleaning mechanism is retracted by being moved away from the imaging surface.  
      These and other objects, advantages and features of the invention will become apparent from the following description thereof taken in conjunction with the accompanying drawings, which illustrate specific embodiments of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and other objects, advantages and features of the invention will become apparent from the following description thereof taken in conjunction with the accompanying drawings in which:  
       FIG. 1  is a block diagram showing a camera mounted with a cleaning apparatus according to the present invention.  
       FIG. 2  is a cross sectional view of the camera mounted with the cleaning apparatus according to a first embodiment of the present invention, showing the condition in which a suction nozzle is in its retracted position.  
       FIG. 3  is a cross sectional view of the camera mounted with the cleaning apparatus according to the first embodiment of the present invention, showing the condition in which the suction nozzle is in its cleaning position.  
       FIG. 4  is a diagram showing the cleaning apparatus according to the first embodiment of the present invention, as viewed from the camera body side.  
       FIG. 5  is a cross sectional view showing a cleaning apparatus according to a second embodiment of the present invention.  
       FIG. 6  is a diagram for explaining a modified example of a suction device in the cleaning apparatus according to the second embodiment of the present invention.  
       FIG. 7  is a diagram for explaining a modified example of a hermetic contact member in the cleaning apparatus according to the second embodiment of the present invention.  
       FIG. 8  is a diagram for explaining another modified example of the hermetic contact member in the cleaning apparatus according to the second embodiment of the present invention.  
       FIG. 9  is a cross sectional view showing a cleaning apparatus according to a third embodiment of the present invention.  
       FIG. 10  is a cross sectional view of the camera mounted with a cleaning apparatus according to a fourth embodiment of the present invention, showing the condition in which a cleaning pad is in its retracted position.  
       FIG. 11  is a cross sectional view of the camera mounted with the cleaning apparatus according to the fourth embodiment of the present invention, showing the condition in which the suction nozzle is in its cleaning position.  
       FIG. 12  is a flow chart for explaining the cleaning operation of the camera cleaning apparatus according to the first, second, and fourth embodiments of the present invention.  
       FIG. 13  is a flow chart for explaining the cleaning operation of the camera cleaning apparatus according to the third embodiment of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Embodiments of a cleaning apparatus according to the present invention will be described below with reference to the accompanying drawings. The embodiments herein will be described for the case of an interchangeable lens type digital camera, but it will be recognized that the camera cleaning apparatus of the present invention is also applicable to an interchangeable lens type silver halide film camera or video camera.  
       FIG. 1  is a block diagram showing a digital camera  1  to which a cleaning apparatus  20  according to the first embodiment of the present invention is attached by detaching the interchangeable lens.  FIG. 2  is a cross sectional view of the digital camera  1  mounted with the cleaning apparatus  20  according to the first embodiment of the present invention; in  FIG. 2 , a suction nozzle  36  is in its retracted position.  FIG. 3  is a cross sectional view of the digital camera  1  when the suction nozzle  36  shown in  FIG. 2  is set in its cleaning position.  FIG. 4  is a diagram showing the cleaning apparatus  20  as viewed from the camera body  2  side.  
      The interchangeable lens type digital camera  1  is constructed so that the interchangeable lens or the cleaning apparatus  20  can be readily attached to and detached from the camera body  2 .  
      As shown in  FIG. 1 , the camera body  2  comprises: a camera CPU  4  for controlling the entire camera; a mirror driving mechanism  6  for driving a main mirror  5  and a sub mirror  7  ( FIG. 2 ); a shutter  8 ; a charge coupled device (CCD)  12 ; and a body side mount  9  to which the cleaning apparatus  20  is to be attached. The camera body  2  further comprises: an operation section  11  for selecting shooting mode, playback mode, display mode, cleaning mode, etc.; a display section  3  for displaying various kinds of information for the camera  1 ; a phase difference AF module  14  ( FIG. 2 ) for detecting the focused condition by using reflected light from the sub mirror  7 ; and a pentaprism  16  ( FIG. 2 ) for directing reflected light from the main mirror  5  into an eye piece.  
      As shown in  FIG. 2 , the main mirror  5  is a half silvered mirror, which reflects a portion of subject light and transmits the remaining portion of the subject light. The sub mirror  7  is disposed underneath the main mirror  5 . The main mirror  5  and the sub mirror  7  are mounted so as to be swingable between the measuring position indicated by dashed lines and the shooting position indicated by solid lines. In the measuring position, the main mirror  5  is tilted at an angle of 45 degrees relative to a shooting light axis  0 , and reflects a portion of the subject light into the pentaprism  16 . The sub mirror  7  in the measuring position reflects the subject light transmitted through the main mirror  5  and thus directs it into the phase difference AF module  14 . The measuring position is set so as to move away from the traveling path of the suction nozzle  36  or a movable cylinder  56  ( FIG. 10 ). In the shooting position, since the main mirror  5  and the sub mirror  7  are moved away from the shooting light path, the subject light is introduced directly onto the imaging device  12 . The main mirror  5  and the sub mirror are swingably supported on a swing axis (not shown), so that the main mirror  5  and the sub mirror  7  are moved together in swinging fashion. The main mirror  5  and the sub mirror  7  are constructed so as to be driven in swinging fashion by the mirror driving mechanism  6  which comprises an electric motor, gear, etc. Accordingly, the main mirror  5  and the sub mirror  7  are moved upward by the mirror driving mechanism  6  into the shooting position (mirror up) or pushed downward into the measuring position (mirror down).  
      The shutter  8  ( FIG. 1 ) is disposed in front of the charged coupled device (CCD)  12  as the imaging device. The shutter  8  is, for example, a focal plane shutter having a front curtain and a rear curtain.  
      The imaging device  12  is a device for converting subject image light into an electrical signal, and is constructed from a photoelectric converting device such as a charge coupled device (CCD) or a complementary MOS (CMOS) device. Usually, an optical filter and a protective glass are arranged one behind the other on the front side, i.e., the subject side of the photoelectric converting device. In this patent specification, of the photoelectric conversion related components such as the photoelectric converting device, protective glass, optical filter, etc., the exposed surface of the component located at the foremost end on the subject side is generally referred to as the imaging surface  13  ( FIG. 2 ).  
      As shown in  FIG. 2 , the mount  9  of the body  2  is a mounting portion for mounting the interchangeable lens or the cleaning apparatus  20  of the present invention, and is formed around its circumference with a groove having a notch (not shown). An engaging protrusion  62  (to be described later) on a mount  29  of the cleaning apparatus  20  engages with the groove (not shown) formed in the mount  9  of the body  2 , thus locking one to the other in the so-called bayonet fashion. In this condition, the mount  29  of the cleaning apparatus  20  is held in contact with the mount  9  of the body  2  via a mount surface M.  
      As shown in  FIG. 1 , the cleaning apparatus  20  comprises a cleaning CPU  22 , a battery (power source)  24 , a cleaning mechanism  28 , and a driving mechanism  30 , which are contained in a cylindrical case  21 . A display section  26  is located on the outside surface of the case  21 . The mount  29  of the cleaning apparatus  20  is provided at the end of the case  21  that faces the camera body  2 .  
      The cleaning CPU  22  controls the entire operation of the cleaning apparatus  20  in cooperation with the camera CPU  4 . The battery (power source)  24  supplies power to the CPU  22 , the cleaning mechanism  28 , and the driving mechanism  30 .  
      As shown in  FIG. 2 , the cleaning mechanism  28  comprises, in addition to the cylindrically shaped suction nozzle (cleaning member)  36 , a dust collecting chamber  46  which communicates with the suction nozzle  36  and collects dust, a suction window  48  which separates the suction nozzle  36  from the dust collecting chamber  46  and thus prevents backflow of dust, and a suction device  42  which applies a negative pressure. Between the dust collecting chamber  46  and the suction device  42  are disposed a suction port  44  connecting between them and a filter  49  for collecting dust.  
      The driving mechanism  30  ( FIG. 1 ) comprises: a guide member  34  which guides the movement of the suction nozzle  36  while maintaining airtightness; a flange portion  37  which is connected to the guide member  34  and has a threaded hole; a guide screw  38  which screws into the threaded hole of the flange portion  37 ; a guide rod  39  which guides the flange portion  37 ; and a positioning motor  32  which drives the guide screw  38 . The rotational driving force of the positioning motor  32 , while being reduced in speed via a gear not shown, drives the guide screw  38  for rotation. Then, the rotational driving force of the guide screw  38  is converted into rectilinear motion that causes the suction nozzle  36  to move along the guide member  34 . The suction nozzle  36  moves in parallel to the shooting light axis O. As shown in  FIG. 3 , the suction nozzle  36  when in dust suction operation is set in the cleaning position in which the suction nozzle  36  protrudes from the mount surface M toward the imaging surface  13  of the imaging device  12 . When not in operation, the suction nozzle  36  is set in the retracted position in which the suction nozzle  36  is retracted from the mount surface M into the cleaning apparatus  20 .  
      In the dust suction operation, the end of the suction nozzle  36  that faces the camera body  2  is located at the cleaning position where the end stops just short of touching the imaging surface  13 . The distance from the mount surface M to the light receiving surface of the CCD (imaging device)  12  is designed and adjusted relative to the mount surface M so that the distance is always the same for all cameras if the cameras are of the same maker. Since the feed amount of the suction nozzle  36  is determined based on these design data, the end of the suction nozzle  36  that faces the camera body  2  does not hit the imaging surface  13  hard. It is also possible to use a light sensor or a ultrasonic sensor to detect how close the end of the suction nozzle  36  on the camera body  2  side is to the imaging surface  13  and to prevent it from hitting the imaging surface  13  by controlling the feed amount.  
      The suction nozzle  36  is provided with an opening  31  at its end that faces the camera body  2 . A suction space  40  is formed inside the suction nozzle  36  and the guide member  34 . The interior space of the camera body  2  communicates with the opening  31 , the suction space  40 , the suction window  48 , the dust collecting chamber  46 , the filter  49 , the suction port  44 , and the suction device  42 , and these component elements form a continuous suction path for sucking dust therethrough.  
      As shown in  FIG. 4 , contacts C as information communicating terminals are provided on the front surface of the mount  29  of the cleaning apparatus. The mount  9  of the body  2  is likewise provided with contacts C as information communicating terminals. When the cleaning apparatus  20  is attached to the camera body  2 , the contacts C on both sides are connected. Between the contacts C on both sides, electrical signals are transferred which concern various operations, such as the presence or absence of the attached cleaning apparatus  20 , information about the remaining capacity in the battery built into the camera body  2  and the battery  24  of the cleaning apparatus  20 , information about the position of the suction nozzle  36 , the open/close state of the shutter  8 , information about the position of the main mirror  5  or the sub mirror  7 , the diving condition of the suction nozzle  36 , or the display status of the display section  3  of the body  2  and the display section  26  of the cleaning apparatus  20 .  
      Next, operations of the camera  1  and the cleaning apparatus  20  will be described with reference to  FIG. 12 .  
      When the operator changes the mode setting to the cleaning mode by operating the operation section  11  provided on the camera body  2 , a series of cleaning operations of the cleaning apparatus  20  is started (step  100 ). The cleaning apparatus  20  is attached to the camera body  2  by engaging the mount  29  of the cleaning apparatus  20  with the mount  9  of the camera body  2  (step  102 ). The contacts C on the body side mount  9  are connected to the contacts C on the cleaning apparatus  20 , and the camera CPU  4  receives a signal notifying that the cleaning apparatus  20  has been attached to the camera body  2  (step  104 ).  
      The camera CPU  4  issues an instruction to check the remaining capacity in the battery built into the camera body  2  and the battery  24  of the cleaning apparatus  20  (step  106 ). It is checked whether the remaining capacity in each battery is sufficient or not (step  108 ). If a signal indicating a low battery is received, the camera CPU  4  issues an instruction to display a pictorial warning symbol or a warning message, saying, for example, “BATTERY IS LOW CLEANING CANNOT BE DONE”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  20  (step  140 ).  
      If a signal indicating that the battery&#39;s remaining capacity is sufficient is received, the camera CPU  4  issues an instruction to move the main mirror  5  and the sub mirror  7  upward (step  110 ) and open the shutter  8  (step  112 ). The mirrors are thus retracted out of the path along which the suction nozzle  36  moves between the cleaning position and the retracted position. The camera CPU  4  sends a cleaning start signal to the cleaning CPU  22  to start the cleaning operation (step  114 ).  
      The cleaning CPU  22  issues an instruction to supply power to the positioning motor  32  in the driving mechanism  30  and to drive the positioning motor  32  to rotate the guide screw  38  and thereby move the suction nozzle  36  from the retracted position to the cleaning position ( FIG. 3 ) where the nozzle end stops just short of touching the imaging device  12  (step  116 ). When suction force is generated by operating the suction device  42 , the dust collecting chamber  46 , the suction space  40 , and the interior space of the camera body  2  are evacuated and the dust adhering to the imaging surface  13  is sucked up, thus starting the cleaning process (step  118 ).  
      The cleaning CPU  22  determines whether the cleaning is completed or not by checking whether the cleaning process has been performed for a predetermined time (step  120 ). If the predetermined time has not yet elapsed from the start of the cleaning process, the cleaning CPU  22  outputs a signal indicating the cleaning in progress, and thus issues an instruction to display a pictorial symbol indicating the cleaning in progress or a message, saying, for example, “CLEANING IS IN PROGRESS”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  20  (step  122 ).  
      When the predetermined time has elapsed from the start of the cleaning process, the cleaning CPU  22  issues an instruction to stop the operation of the suction device  42 , thus terminating the cleaning process. The cleaning CPU  22  issues an instruction to supply power to the positioning motor  32  and to drive the positioning motor  32  to rotate in the reverse direction and thereby move the suction nozzle  36  from the cleaning position to the prescribed retracted position ( FIG. 2 ) (step  124 ). When the suction nozzle  36  has moved to the prescribed retracted position, the cleaning CPU  22  sends to the camera CPU  4  a signal indicating that the cleaning is completed (step  126 ).  
      Upon receiving the cleaning completion signal, the camera CPU  4  issues an instruction to close the shutter  8  (step  128 ) and move the main mirror  5  and the sub mirror  7  downward (step  130 ). When the shutter  8  is closed, and the main mirror  5  and the sub mirror  7  are moved downward, the series of cleaning operations is terminated (step  132 ).  
      A cleaning apparatus  120  for a digital camera  1 , according to a second embodiment of the invention, will be described in detail with reference to FIGS.  5  to  8 . The basic construction relating to the digital camera  1  is the same as that shown in the foregoing first embodiment, and therefore, the following description focuses on differences from the first embodiment. In the second embodiment, the same component members as those in the first embodiment are designated by the same reference numerals.  
      The cleaning apparatus  120  according to the second embodiment comprises a cleaning CPU  22 , a battery (power source)  124 , a cleaning mechanism  128 , and a driving mechanism  130 , which are contained in a cylindrical case  121 . A display section  26  is located on the outside surface of the cylindrical case  121 . The mount  129  of the cleaning apparatus  120  is provided at the end of the cylindrical case  121  that faces the camera body  2 .  
      The cleaning CPU controls the entire operation of the cleaning apparatus  120  in cooperation with the camera CPU  4 . The battery (power source)  124  supplies power to the cleaning CPU  22 , the cleaning mechanism  128 , and the driving mechanism  130 .  
      The cleaning mechanism  128  comprises a cylindrically shaped suction nozzle (cleaning member)  136 , a dust collecting chamber  46  which communicates with the suction nozzle  136  and collects dust, a suction window  148  which separates the suction nozzle  136  from the dust collecting chamber  46  and thus prevents backflow of dust, a bag-like container  47  which collects dust, and a suction device  42  which applies a negative pressure. Between the dust collecting chamber  46  and the suction device  42  is disposed a suction port  44  connecting between them. A hermetic contact member  43  which maintains airtightness is attached to the suction nozzle  136  at the end thereof that faces the camera body  2 .  
      Various soft members that do not scratch the imaging surface  13  can be used for the hermetic contact member  43 . As shown in  FIGS. 7 and 8 , use can be made, for example, of a silicone cloth such as that often used to wipe lenses, unwoven fabric of super fine acrylic, polyester, or nylon fiber such as that used to wipe glasses, a sponge-like pad, or a brush or the like.  
      The driving mechanism  130  comprises: a guide member  34  which guides the movement of the suction nozzle  136  while maintaining airtightness; a flange portion  137  which is connected to the guide member  34  and has a threaded hole; a guide screw  138  which screws into the threaded hole of the flange portion  137 ; and a positioning motor  132  which drives the guide screw  138 . The rotational driving force of the positioning motor  132 , while being reduced in speed via a gear not shown, drives the guide screw  138  for rotation. Then, the rotational driving force of the guide screw  138  is converted into rectilinear motion that causes the suction nozzle  136  to move along the guide member  34 . When in dust suction operation, the suction nozzle  136  is set in the cleaning position in which the suction nozzle  136  protrudes from the mount surface M toward the imaging surface  13  of the imaging device  12 . When not in operation, the suction nozzle  136  is set in the retracted position in which the suction nozzle  136  is retracted from the mount surface M into the cleaning apparatus  120 .  
      In the dust suction operation, the hermetic contact member  43  attached to the end of the suction nozzle  136  that faces the camera body  2  is located at the cleaning position where the hermetic contact member  43  lightly touches the imaging surface  13  of the imaging device  12 . Since the hermetic contact member  43  is in intimate contact with the imaging surface  13  of the imaging device  12 , dust can be collected using a relatively weak suction force. Though the hermetic contact member  43  is made to lightly touch the imaging surface  13 , the imaging surface  13  is not scratched because the hermetic contact member  43  is made of a soft material.  
      The suction nozzle  136  is provided with an opening  31  at its end that faces the camera body  2 . A suction space  40  is formed inside the suction nozzle  136  and the guide member  34 . The interior space of the camera body  2  communicates with the opening  31 , the suction space  40 , the suction window  148 , the dust collecting container  47 , the dust collecting chamber  46 , the suction port  44 , and the suction device  42 , and these component elements form a continuous suction path for sucking dust therethrough.  
      Contacts C as information communicating terminals are provided on the front surface of the mount  129  of the cleaning apparatus  120 . The mount  9  of the body  2  is likewise provided with contacts C as information communicating terminals. When the cleaning apparatus  120  is attached to the camera body  2 , the contacts C on both sides are connected. Between the contacts C on both sides, electrical signals are transferred which concern various operations, such as the presence or absence of the attached cleaning apparatus  120 , information about the remaining capacity in the battery built into the camera body  2  and the battery  124  of the cleaning apparatus  120 , information about the position of the suction nozzle  136 , the open/close state of the shutter  8 , information about the position of the main mirror  5  or the sub mirror  7 , the driving condition of the suction nozzle  136 , or the display status of the display section  3  of the body  2  and the display section  26  of the cleaning apparatus  120 .  
      As shown in  FIG. 6 , the cleaning mechanism  128  can also be constructed by including in the suction device  42  a filter  49  for collecting dust and a fan  45  which is driven by a motor  41 . With this simple structure, dust can be effectively sucked by applying a negative pressure to the suction space  40  which extends all the way to the imaging device  12 .  
      The operations of the camera  1  and the cleaning apparatus  120  in the second embodiment are the same as those described in the first embodiment, and therefore, the description will not be repeated here.  
      A cleaning apparatus  220  for a digital camera  1 , according to a third embodiment of the invention, will be described in detail with reference to  FIG. 9 . The basic construction relating to the digital camera  1  is the same as that shown in the previously described first embodiment, and therefore, the following description focuses on differences from the first embodiment. In the third embodiment, the same component members as those in the first or second embodiment are designated by the same reference numerals.  
      The cleaning apparatus  220  according to the third embodiment is constructed so that the suction nozzle  236  is moved manually, and the suction device is external to the cleaning apparatus  220 .  
      The cleaning apparatus  220  includes a substantially cylindrically shaped case  221  having a mount  229 . The mount  229  of the cleaning apparatus  220  has an engaging protrusion  62  which is biased by a spring or the like outwardly in a radial direction. The engaging protrusion  62  is fitted in bayonet fashion into the groove (not shown) formed in the mount  9  of the body  2 . A contact C as an information communicating terminal for notifying the camera CPU  4  of the presence or absence of the attached cleaning apparatus  220  is provided on the end face of the mount  229  of the cleaning apparatus  220  that faces the camera body  2 .  
      The case  221  has an external nozzle fixing mount  60  at its subject side end. The external nozzle fixing mount  60  has a mounting protrusion  66  which is biased by a spring or the like toward the center. When the external suction nozzle  64  is inserted in an external suction port  61  of the external nozzle fixing mount  60 , the external suction nozzle  64  is engaged with the mounting protrusion  66  and is thus held fixed in the external suction port  61 .  
      The case  221  has in its outer surface a guide hole  51  extending in a longitudinal direction. The length of the guide hole  51  is chosen so that, when the suction nozzle  236  is moved toward the imaging device  12  and set in the cleaning position, the hermetic contact member  43  lightly touches the imaging surface  13  of the imaging device  12 .  
      The cylindrically shaped suction nozzle (cleaning member)  236  is constructed so that it can move rectilinearly along the inside wall surface of the case  221 . The hermetic contact member  43  made of a soft material, similar to the one described in the second embodiment, is attached to the suction nozzle  236  at the end thereof that faces the camera body  2 .  
      The suction nozzle  236  has an outwardly protruding operation lever  53 . The operation lever  53  is inserted through the guide hole  51 , and can be moved in sliding fashion along the longitudinal direction. Accordingly, when the operator slides the operation lever  53  toward the camera body  2 , the suction nozzle  236  moves toward the cleaning position. Conversely, when the operator slides the operation lever  53  toward the subject side, the suction nozzle  236  moves toward the retracted position.  
      The suction nozzle  236  is provided with an opening  31  at its end that faces the camera body  2 . A suction space  40  is formed in a space inside the suction nozzle  236  and the case  221 . The interior space of the camera body  2  communicates with the opening  311  the suction space  40 , the interior space of the external suction nozzle  64 , and the external suction device not shown, and these component elements form a continuous suction path for sucking dust therethrough.  
      A vent hole  57  is formed in the outer surface of the case  221 . A constant pressure valve  55  is provided on the inside wall surface of the case  221  in such a manner as to close the vent hole  57 . That is, the constant pressure valve  55  is provided at an intermediate point in the suction path. A conventional vacuum cleaner, such as one used in a home, is used as the external suction device. If the suction force of the conventional vacuum cleaner is too strong, that is, if a suction force is exerted that is greater than a predetermined suction force, the constant pressure valve  55  is opened to introduce the outside air through the vent hole  57 , preventing the pressure inside the suction path from being excessively reduced.  
      Next, operations of the camera  1  and the cleaning apparatus  120  according to the third embodiment will be described with reference to  FIG. 13 .  
      When the operator changes the mode setting to the cleaning mode by operating the operation section  11  provided on the camera body  2 , a series of cleaning operations of the cleaning apparatus  220  is started (step  200 ). The cleaning apparatus  220  is attached to the camera body  2  by engaging the mount  229  of the cleaning apparatus  220  with the mount  9  of the camera body  2  (step  202 ). The contacts C on the body side mount  9  are connected to the contacts C on the cleaning apparatus  220 , and the camera CPU  4  receives a signal notifying that the cleaning apparatus  220  has been attached to the camera body  2 .  
      The camera CPU  4  issues an instruction to check the remaining capacity in the battery built into the camera body  2  and the battery  224  of the cleaning apparatus  220  (step  206 ). It is checked whether the remaining capacity in each battery is sufficient or not (step  208 ). If a signal indicating a low battery is received, the camera CPU  4  issues an instruction to display a pictorial warning symbol or a warning message, saying, for example, “BATTERY IS LOW CLEANING CANNOT BE DONE”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  220  (step  240 ).  
      If a signal indicating that the battery&#39;s remaining capacity is sufficient is received, the camera CPU  4  issues an instruction to move the main mirror  5  and the sub mirror  7  upward (step  210 ) and open the shutter  8  (step  212 ). The mirrors are thus retracted out of the path along which the suction nozzle  236  moves between the cleaning position and the retracted position. The camera CPU  4  issues an instruction to display a pictorial symbol prompting the user to move the suction nozzle  236  to the cleaning position or an instruction message, saying, for example, “MOVE THE CLEANING MEMBER TO THE CLEANING POSITION”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  220  (step  214 ).  
      The user viewing the display moves the suction nozzle  236  to the cleaning position by moving the operation lever  53  of the cleaning apparatus  220  toward the camera body  2  (step  216 ). When the cleaning CPU  22  receives from a light sensor or the like a signal indicating that the suction nozzle  236  has been moved to the cleaning position, then the dust collecting chamber  46 , the suction space  40 , and the interior space of the camera body  2  are evacuated and the dust adhering to the imaging surface  13  is sucked up, thus starting the cleaning process (step  218 ).  
      The cleaning CPU  22  determines whether the cleaning is completed or not by checking whether the cleaning process has been performed for a predetermined time (step  220 ). If the predetermined time has not yet elapsed from the start of the cleaning process, the cleaning CPU  22  outputs a signal indicating the cleaning in progress, and thus issues an instruction to display a pictorial symbol indicating the cleaning in progress or a message, saying, for example, “CLEANING IS IN PROGRESS”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  20  (step  222 ).  
      When the predetermined time has elapsed from the start of the cleaning process, the cleaning CPU  22  issues an instruction to stop the operation of the suction device  42 , thus stopping the operation of the suction device  42 , and sends a signal indicating that the operation of the suction device  42  has been stopped. Upon receiving the signal indicating that the operation of the suction device  42  has been stopped, the camera CPU  4  issues an instruction to display a pictorial symbol prompting the user to retract the cleaning member or an instruction message, saying, for example, “MOVE THE CLEANING MEMBER TO THE RETRACTED POSITION”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  220 . The user viewing the display moves the suction nozzle  236  to the retracted position by moving the operation lever  53  of the cleaning apparatus  220  toward the subject side (step  224 ).  
      When a signal is received from a light sensor or the like indicating that the suction nozzle  236  has been moved to the retracted position, the cleaning CPU  22  sends to the camera CPU  4  a signal indicating that the cleaning is completed (step  226 ).  
      Upon receiving the cleaning completion signal, the camera CPU  4  issues an instruction to close the shutter  8  (step  228 ) and move the main mirror  5  and the sub mirror  7  downward (step  230 ). When the shutter  8  is closed, and the main mirror  5  and the sub mirror  7  are moved downward, the series of cleaning operations is terminated (step  232 ).  
      A cleaning apparatus  320  for a digital camera  1 , according to a fourth embodiment of the invention, will be described in detail with reference to FIGS.  10  to  12 . The basic construction relating to the digital camera  1  is the same as that shown in the previously described first embodiment, and therefore, the following description focuses on differences from the first embodiment. In the fourth embodiment, the same component members as those in the first, second, or third embodiment are designated by the same reference numerals.  
      The cleaning apparatus  320  according to the fourth embodiment comprises a cleaning CPU  22  (not shown), a battery (power source)  324 , a cleaning mechanism  328 , and a driving mechanism  330 , which are contained in a cylindrical case  321 . A display section  26  (not shown) is located on the outside surface of the cylindrical case  321 . The mount  329  of the cleaning apparatus  320  is provided at the end of the cylindrical case  321  that faces the camera body  2 .  
      The cleaning CPU  22  controls the entire operation of the cleaning apparatus  320  in cooperation with the camera CPU  4 . The battery (power source)  324  supplies power to the cleaning CPU  22 , the cleaning mechanism  328 , and the driving mechanism  330 .  
      The cleaning mechanism  328  comprises a soft cleaning pad (cleaning member)  54  and a cleaning motor  52  which drives the cleaning pad  54  for rotation. The cleaning motor  52  is mounted inside the movable cylinder  56  in the end portion thereof that faces the camera body  2 .  
      Various soft members that do not scratch the imaging surface  13  of the imaging device  12  can be used for the soft cleaning pad  54 . For example, use can be made of a silicone cloth such as that often used to wipe lenses, unwoven fabric of super fine acrylic, polyester, or nylon fiber such as that used to wipe glasses, a sponge-like pad, or a brush or the like.  
      The driving mechanism  330  comprises: the movable cylinder  56  to which the cleaning pad  54  is attached; a flange portion  337  which is connected to the movable cylinder  54  and has a threaded hole; a guide screw  338  which screws into the threaded hole of the flange portion  337 ; a guide rod  339  which guides the flange portion  337 ; and a positioning motor  332  which drives the guide screw  338 . The rotational driving force of the positioning motor  332 , while being reduced in speed via a gear not shown, drives the guide screw  338  for rotation. Then, the rotational driving force of the guide screw  338  is converted into rectilinear motion that causes the movable cylinder  56  to move along the guide rod  39 . When in dust cleaning operation, the movable cylinder  56  is set in the cleaning position in which the movable cylinder  56  protrudes from the mount surface M toward the imaging device  12 . When not in operation, the movable cylinder  56  is set in the retracted position in which the movable cylinder  56  is retracted from the mount surface M into the cleaning apparatus  320 .  
      In the dust suction operation, the cleaning pad  54  attached to the outside of the end of the movable cylinder  56  that faces the camera body  2  is located at the cleaning position where the cleaning pad  54  lightly touches the imaging surface  13  of the imaging device  12 . When the cleaning pad  54  is driven for rotation, the dust adhering to the imaging surface  13  is wiped off. Though the cleaning pad  54  is made to lightly touch the imaging surface  13  of the imaging device  12 , the imaging surface  13  is not scratched because the cleaning pad  54  is made of a soft material.  
      Contacts C as information communicating terminals are provided on the front surface of the mount  329  of the cleaning apparatus  320 . The mount  9  of the body  2  is likewise provided with contacts C as information communicating terminals. When the cleaning apparatus  320  is attached to the camera body  2 , the contacts C on both sides are connected. Between the contacts C on both sides, electrical signals are transferred which concern various operations, such as the presence or absence of the attached cleaning apparatus  320 , information about the remaining capacity in the battery built into the camera body  2  and the battery  324  of the cleaning apparatus  320 , information about the position of the movable cylinder  56 , the open/close state of the shutter  8 , information about the position of the main mirror  5  or the sub mirror  7 , the driving condition of the movable cylinder  56 , or the display status of the display section  3  of the body  2  and the display section  26  of the cleaning apparatus  320 .  
      Next, operations of the camera  1  and the cleaning apparatus  320  according to the fourth embodiment will be described with reference to  FIG. 12 .  
      When the operator changes the mode setting to the cleaning mode by operating the operation section  11  provided on the camera body  2 , a series of cleaning operations of the cleaning apparatus  320  is started (step  100 ). The cleaning apparatus  320  is attached to the camera body  2  by engaging the mount  329  of the cleaning apparatus  320  with the mount  9  of the camera body  2  (step  102 ). The contacts C on the mount  9  of the body  2  are connected to the contacts C on the cleaning apparatus  320 , and the camera CPU  4  receives a signal notifying that the cleaning apparatus  320  has been attached to the camera body  2 .  
      The camera CPU  4  issues an instruction to check the remaining capacity in the battery built into the camera body  2  and the battery  324  of the cleaning apparatus  320  (step  106 ). It is checked whether the remaining capacity in each battery is sufficient or not (step  108 ). If a signal indicating a low battery is received, the camera CPU  4  issues an instruction to display a pictorial warning symbol or a warning message, saying, for example, “BATTERY IS LOW CLEANING CANNOT BE DONE”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  320  (step  140 ).  
      If a signal indicating that the battery&#39;s remaining capacity is sufficient is received, the camera CPU  4  issues an instruction to move the main mirror  5  and the sub mirror  7  upward (step  110 ) and open the shutter  8  (step  112 ). The mirrors are thus retracted out of the path along which the movable cylinder  56  moves. The camera CPU  4  sends an instruction to the cleaning CPU  22  to start the cleaning operation (step  114 ).  
      The cleaning CPU  22  issues an instruction to supply power to the positioning motor  332  and to drive the positioning motor  332  to rotate the guide screw  338  and thereby move the movable cylinder  56  from the retracted position to the cleaning position where it lightly touches the imaging device  12  (step  116 ). The cleaning CPU  22  starts the cleaning process, that is, power is supplied to the cleaning motor  52  and the cleaning motor  52  is driven to rotate the cleaning pad  54  which thus operates to wipe out the dust adhering on the imaging surface  13  of the imaging device  12  (step  118 ).  
      The cleaning CPU  22  determines whether the cleaning is completed or not by checking whether the cleaning process has been performed for a predetermined time (step  120 ). If the predetermined time has not yet elapsed from the start of the cleaning process, the cleaning CPU  22  outputs a signal indicating the cleaning in progress, and thus issues an instruction to display a pictorial symbol indicating the cleaning in progress or a message, saying, for example, “CLEANING IS IN PROGRESS”, at least either on the display section  3  of the body  2  or on the display section  26  of the cleaning apparatus  320  (step  122 ).  
      When the predetermined time has elapsed from the start of the cleaning process, the cleaning CPU  22  issues an instruction to stop the rotation of the cleaning motor  52 , thus terminating the cleaning process. The cleaning CPU  22  issues an instruction to supply power to the positioning motor  332  and to drive the positioning motor  332  to rotate the guide screw  338  in the reverse direction and thereby move the movable cylinder  56  from the cleaning position to the prescribed retracted position (step  124 ). When the movable cylinder  56  has moved to the prescribed retracted position, the cleaning CPU  22  sends to the camera CPU  4  a signal indicating that the cleaning is completed (step  126 ).  
      Upon receiving the cleaning completion signal, the camera CPU  4  issues an instruction to close the shutter  8  (step  128 ) and move the main mirror  5  and the sub mirror  7  downward (step  130 ). When the shutter  8  is closed, and the main mirror  5  and the sub mirror  7  are moved downward, the series of cleaning operations is terminated (step  132 ).  
      Here, the cleaning pad  54  may be driven by rotating as described above, or may be driven by applying fine vibrations in a known manner. Further, the cleaning apparatus may be constructed by combining the earlier described suction type with the cleaning pad type. While the above description has dealt with a digital camera having an imaging device  12 , it will be appreciated that the invention is also applicable for cleaning the imaging surface and its surroundings in a silver halide film camera which does not have such an imaging device  12 .  
      As described above, the camera cleaning apparatus of the present invention can be readily attached to and detached from the camera mount, just like an interchangeable lens, and is attached to the camera body by detaching the interchangeable lens only when dust removal is needed. Further, in the cleaning apparatus attached to the mount of the camera body, the cleaning member is moved by the moving mechanism from the retracted position, where the cleaning member is distanced away from the imaging surface, to the cleaning position, where it is positioned close to the imaging surface, and vice versa. When not used for cleaning, the cleaning member is retracted into the retracted position so that it does not protrude outside the cleaning apparatus; this not only serves to prevent the cleaning member from accidentally hitting the main mirror or the shutter inside the camera body when attaching the cleaning apparatus to the camera body, but also contributes to reducing the size of the cleaning apparatus.  
      Although the present invention has been fully described by way of examples with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Therefore, unless otherwise such changes and modifications depart from the scope of the present invention, they should be construed as being included therein.