Patent Publication Number: US-7912398-B2

Title: Image forming apparatus cleaning device actuated by door or paper feeding cassette

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Korean Patent Application No. 2007-80001, filed in the Korean Intellectual Property Office on Aug. 9, 2007, the disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Aspects of the present invention relate to an image forming apparatus, and more particularly, to an image forming apparatus having a cleaning device to remove foreign substances attached to inner components. 
     2. Description of the Related Art 
     An image forming apparatus is an apparatus that prints an image onto a printable medium, such as paper, according to an inputted image signal. An electrophotographic type image forming apparatus is configured such that light is scanned to a photosensitive body charged with a predetermined electric potential so as to form an electrostatic latent image on an outer surface of the photosensitive body. The electrostatic latent image is developed into a toner image by supplying a toner to the electrostatic latent image, and the toner image is transferred and fused onto a printable medium. 
     An electrophotographic image forming apparatus generally includes a laser scanning device to form an electrostatic latent image on a photosensitive body. The laser scanning device includes a housing with a light transmitting member. Optical components, such as a light source, an optical deflector, an f-theta (fθ) lens, a mirror, and the like, are mounted inside the housing. The light emitted from the light source is deflected in a main scanning direction by the optical deflector, and is guided toward the light transmitting member mounted to the housing via the f-theta lens and the mirror. The light is scanned outside the housing through the light transmitting member. 
     If foreign substances in the image forming apparatus, such as paper dust or toner, are attached to the light transmitting member of the laser scanning device, the foreign substances partially interrupt the light scanned to the photosensitive body from the laser scanning device and disturb the formation of the electrostatic latent image, which causes deterioration of print quality. 
     To cope with this problem, Japanese Patent Laid-Open Publication No. 2004-341042 (“reference 1”) discloses a cleaning device of a laser scanning device to clean a light transmitting member (dustproof glass) by spraying compressed air supplied from an external source into the light transmitting member. Korean Patent Registration No. 0547137, published as KR 2005-20379 (“reference 2”) discloses a cleaning device of a laser scanning device to remove foreign substances attached to an outer surface of a light transmitting member by blowing air through a blower fan. However, the cleaning device disclosed in reference 1 is not practical because a user needs to perform a connecting work with a compressed air supply source provided separately whenever cleaning the light transmitting member. Further, the disclosed cleaning device gives a user inconvenience of participating in the cleaning work for the light transmitting member each time. 
     The cleaning device disclosed in reference 2 has an advantage of conveniently cleaning the light transmitting member using a blower fan. However, an additional driving source to drive the blower fan increases component costs. Further, when a space around the laser scanning device is small, there is a limitation in mounting the blower fan near the light transmitting member. 
     SUMMARY OF THE INVENTION 
     Aspects of the present invention provide an image forming apparatus and a cleaning device thereof that is capable of conveniently cleaning inner components without an additional driving source. 
     According to an aspect of the invention, an image forming apparatus to form an image onto a printable medium is provided. The image forming apparatus comprises a main body having a main body frame and a moving part provided movably relative to the main body frame; a laser scanning device; and a compressed air supply unit to compress air by interlocking with movement of the moving part and to supply the compressed air to the laser scanning device so as to clean the laser scanning device. 
     According to another aspect of the present invention, the moving part includes a cover hingedly coupled to the main body frame so as to selectively allow access to the interior of the image forming apparatus. The compressed air supply unit may be mounted adjacent to a rotational center of the cover and the laser scanning device. 
     According to another aspect of the present invention, the moving part includes a paper feeding cassette removably mounted to the main body frame. 
     According to another aspect of the present invention, the compressed air supply unit includes a cylinder coupled to the main body frame and a piston coupled to the moving part. 
     According to another aspect of the present invention, the image forming apparatus further comprises at least one connecting pipe to guide the compressed air in the compressed air supply unit to the laser scanning device. The connecting pipe may be made of a flexible material. 
     According to another aspect of the present invention, the laser scanning device include a light transmitting member; and the image forming apparatus further comprises a spray member mounted near the light transmitting member. The spray member may have a spray hole to spray the compressed air supplied from the compressed air supply unit to the light transmitting member. 
     According to another aspect of the present invention, the image forming apparatus further comprises a valve member mounted to the spray member to open and close the spray hole. 
     According to another aspect of the invention, an image forming apparatus is provided. The image forming apparatus comprises a main body having a main body frame and a cover hingedly coupled to the main body frame; a cylinder including an air compression unit; a piston having a first end to move in the air compression unit in a reciprocating fashion so as to compress air, and a second end portion coupled to the cover; an object to be cleaned by the air compressed in the cylinder; and at least one connecting pipe to guide the compressed air to the object to be cleaned. 
     According to another aspect of the present invention, the image forming apparatus further comprises a photosensitive body, and a laser scanning device having a housing provided with a light transmitting member. The laser scanning device scans light to the photosensitive body through the light transmitting member to form an electrostatic latent image onto the photosensitive body. The object to be cleaned includes the light transmitting member. 
     According to another aspect of the present invention, the piston compresses the air by moving along a rotational trajectory of the cover. 
     According to another aspect of the present invention, the piston includes a piston rod having an arc shape, and the air compression part has an arc shape corresponding to the shape of the piston rod. 
     According to another aspect of the invention, an image forming apparatus is provided. The image forming apparatus comprises a main body frame; a paper feeding cassette removably mounted to the main body frame; a cylinder fixed to the main body frame; a piston having a first end to move in the cylinder in a reciprocating fashion so as to compress air, and a second end connected to the paper feeding cassette; an object to be cleaned by the air compressed in the cylinder; and at least one connecting pipe to guide the compressed air to the object to be cleaned. 
     According to another aspect of the invention, a cleaning device to clean a component mounted in an image forming apparatus is provided. The cleaning device comprises a compressed air supply unit having a cylinder and a piston to move in the cylinder in a reciprocating fashion so as to compress air; and at least one connecting pipe having a first end communicating with the cylinder, and a second end extending toward the component to be cleaned. The connecting pipe may be made of a flexible material. 
     According to another aspect of the present invention, the compressed air supplied from the compressed air supply unit is sprayed to a light transmitting member provided in a laser scanning device of the image forming apparatus. 
     Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, of which: 
         FIG. 1  is a view illustrating a constitution of an image forming apparatus according to an embodiment of the present invention; 
         FIG. 2  is a perspective view illustrating a laser scanning device and a spray member in the image forming apparatus according to an embodiment of the present invention; 
         FIG. 3  is a sectional view illustrating a constitution of a cleaning device in the image forming apparatus according to an embodiment of the present invention; 
         FIG. 4  is a perspective view illustrating a mounting structure of a compressed air supply unit in the image forming apparatus according to an embodiment of the present invention; 
         FIG. 5  is a view illustrating a state in which a cover is opened in the image forming apparatus shown in  FIG. 1 ; 
         FIG. 6  is a view illustrating a modified example of a mounting position and a structure of a compressed air supply unit in the image forming apparatus according to an embodiment of the present invention; 
         FIG. 7  is a sectional view illustrating a constitution of the compressed air supply unit shown in  FIG. 6 ; and 
         FIG. 8  is a view illustrating a modified example of compressing air by the compressed air supply unit interlocking with components other than the cover. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures. 
       FIG. 1  shows an image forming apparatus  100  according to an embodiment of the present invention, and  FIG. 2  shows a laser scanning device and a spray member according to an embodiment of the present invention.  FIG. 3  shows a cleaning device according to an embodiment of the present invention, and  FIG. 4  shows a mounting structure of a compressed air supply unit according to an embodiment of the present invention. 
     As shown in  FIG. 1 , the image forming apparatus  100  according to an embodiment of the present invention includes a main body  10 , a paper feeding device  20 , a laser scanning device  30 , a developing device  40 , a fusing device  50 , and a paper discharge device  50 . According to other aspects of the present invention, the image forming apparatus  100  may have additional and/or different components; for example, an ink-jet type image forming apparatus may not include a fuser or a laser scanning device. Similarly, the functionality of two or more of the above units may be combined into a single component. The image forming apparatus  100  may also be included in a multifunction device including copy, a scan, and/or facsimile functions in addition to the printing function. 
     The paper feeding device  20  supplies a printable medium, such as a paper S. The laser scanning device  30  scans light corresponding to image information onto a photosensitive body. The developing device  40  develops an image on the printable medium using the image scanned onto the photosensitive body. The fusing device  50  fuses the image to the printable medium by applying heat and pressure to the printable medium, and the paper discharge device  60  discharges the printable medium having the image to the exterior of the main body  10 . 
     The main body  10  includes a main body frame  10   a  to house and support components of the image forming apparatus  100  and a moving part  10   b  provided movably relative to the main body frame  10   a . The moving part  10   b  may be a cover  11  hingedly coupled to the main body frame  10   a  to allow access to the interior of the image forming apparatus  100 . A user can access the interior of the main body  10  by opening the cover  11 , and can repair or replace the components arranged within or remove jammed paper. The moving part  10   b  may also be a paper feeding cassette  21  that can be mounted and removed while moving relative to the main body frame  10   a . The paper feeding cassette  21  may be a component of the paper feeding device  20 . The paper feeding cassette  21  may also be considered as a part of the main body  10  in the respect of forming a portion of an exterior appearance. 
     The paper feeding device  20  includes the aforesaid paper feeding cassette  21  to receive the paper S, a pickup roller  22 , and a feeding roller  23 . The pickup roller  22  picks up the paper S in the paper feeding cassette  21  sheet by sheet, and the feeding roller  23  feeds the picked-up paper S toward the developing device  40 . The paper feeding cassette  21  is removably coupled to the main body frame  10   a  so as to allow the user to remove the paper feeding cassette  21  and insert additional printable media. However, the cassette need not be used in all aspects, such as where the paper feeding device  20  is a tray holding printable media. 
     As shown in  FIGS. 1 and 2 , the laser scanning device  30  includes a housing  31  having a light transmitting member  31   a  so that light can be irradiated to the outside, and a scanning optical system mounted in the housing  31 . The scanning optical system includes a light source  32  to emit light according to an image signal, an optical deflector  33 , an f-theta (fθ) lens  34 , and a mirror  36 . The optical deflector deflects the light emitted from the light source  32  so as to be scanned to a photosensitive body  41  of the developing device  40 . The f-theta (fθ) lens  34  corrects aberration included in the light deflected from the optical deflector  33 , and the mirror  36  reflects the light passing through the f-theta lens  34  toward the photosensitive body  41 . The optical deflector  33  includes a driving source  33   a , and a polygon mirror  33   b  rotating by the driving source  33   a . The polygon mirror  33   b  has plural reflecting surfaces at a side portion to deflection-scan the light incident from the light source  32  while being rotated by the driving source  33   a . A collimating lens  37  and a cylindrical lens  38  are mounted in an optical path between the light source  32  and the optical deflector  33 . The collimating lens  37  condenses the divergent light emitted from the light source  32  into parallel light or convergent light, and the cylindrical lens  38  converts the light passing through the collimating lens  37  into linear light. 
     In the laser scanning device  30  as structured above, the light emitted from the light source  32  passes through the collimating lens  37 , the cylindrical lens  38 , the polygon mirror  33   b , and the f-theta lens  34  in sequence, and is reflected toward the light transmitting member  31   a  by the mirror  36 . The light reflected from the mirror  36  is emitted to the outside of the housing  31  through the light transmitting member  31   a , and is irradiated to the photosensitive body  41  of the developing device  40 , thereby forming an electrostatic latent image corresponding to image information on the surface of the photosensitive body  41 . The particular structure of the laser scanning device  30  is not limiting; the laser scanning device  30  according to other aspects of the invention may be configured in a different fashion. 
     The developing device  40  includes the aforesaid photosensitive body  41  on which an electrostatic latent image is formed by the laser scanning device  30 , a charge roller  42  to charge the photosensitive body  41 , four developing cartridges  43 Y,  43 M,  43 C and  43 K, an intermediate transfer belt  44 , a first transfer roller  45 , and a second transfer roller  46 . The four developing cartridges  43 Y,  43 M,  43 C, and  43 K develop the electrostatic latent image formed on the photosensitive body  41  into a toner image using toners of yellow, magenta, cyan, and black. Each of the developing cartridges  43 Y,  43 M,  43 C and  43 K includes a developing roller  47  to develop the electrostatic latent image formed on the photosensitive body  41  by supplying the toner thereto, and a supply roller  48  to supply the toner to the developing roller  47  by rotating while contacting the developing roller  47 . A monochrome image forming apparatus may include just one developing cartridge  43 K having black toner. Other colors, and other numbers of colors, may be used in addition to or instead of the exemplary cyan, magenta, yellow, and black colors. 
     The intermediate transfer belt  44  is supported by support rollers  49   a  and  49   b , and runs at the same velocity as a rotational linear velocity of the photosensitive body  41 . The first transfer roller  45  opposes the photosensitive body  41 , and transfers the toner image developed on the photosensitive body  41  onto the intermediate transfer belt  44 . The second transfer roller  46  opposes the intermediate transfer belt  44 . While the toner image is transferred onto the intermediate transfer belt  44  from the photosensitive body  41 , the second transfer roller  46  is spaced apart from the intermediate transfer belt  44 . When the toner image is completely transferred onto the intermediate transfer belt  44 , the second transfer roller  46  comes into contact with the intermediate transfer belt  44  with a predetermined pressure. The toner image on the intermediate transfer belt  44  is transferred onto the paper while the second transfer roller  46  is in contact with the intermediate transfer belt  44 . 
     The fusing device  50  includes a heating roller  51  having a heat source to heat the toner image-transferred paper and a press roller  52  mounted while opposing the heating roller  51  and maintaining a constant fusing pressure with the heating roller  51 . The paper discharge device  60  includes a discharge roller  61  to feed the paper passing through the fusing device  50  to the outside of the main body  10 . 
     The operation of the above-structured image forming apparatus will now be explained briefly. The laser scanning device  30  irradiates light corresponding to yellow image information to the photosensitive body  41  charged with a uniform electric potential by the charge roller  42 , and an electrostatic latent image corresponding to the yellow image is formed on the photosensitive body  41 . A developing bias is applied to the developing roller  47  of the yellow developing cartridge  43 Y, and the yellow toner attaches to the electrostatic latent image to develop the electrostatic latent image into a yellow toner image on the photosensitive body  41 . The toner image is transferred onto the intermediate transfer belt  44  by the first transfer roller  45 . 
     When the yellow toner image corresponding to one page is completely transferred, the laser scanning device  30  scans light corresponding to magenta image information to the photosensitive body  41  to form an electrostatic latent image corresponding to the magenta image. The magenta developing cartridge  43 M supplies the magenta toner to the electrostatic latent image to develop the electrostatic latent image into a magenta toner image. The magenta toner image formed on the photosensitive body  41  is transferred onto the intermediate transfer belt  44  over the yellow toner image that has already been transferred. 
     When the toner images of cyan and black are sequentially transferred onto the intermediate transfer belt  44  through the same procedures as above, a color toner image is formed on the intermediate transfer belt  44  by the overlapping toner images of yellow, magenta, cyan and black. The color toner image is transferred onto the paper passing between the intermediate transfer belt  44  and the second transfer roller  46 . The image transferred onto the paper is fused to the paper by heat and pressure while passing through the fusing device  50 , and the paper having passed through the fusing device  50  is discharged outside by the discharge roller  61 . 
     In the above image forming process, if foreign substances, such as paper dust or toner, are attached to the light transmitting member  31   a  of the laser scanning device  30 , the light scanned to the photosensitive body  41  is partially interrupted, and thus an electrostatic latent image cannot be formed properly on the photosensitive body  41 , causing deterioration of print quality. 
     To cope with this problem, the image forming apparatus  100  includes a cleaning device to clean the light transmitting member  31   a  of the laser scanning device  30 . As shown in  FIGS. 1 ,  3  and  4 , the cleaning device includes a compressed air supply unit  110  to compress air and to supply the compressed air to the light transmitting member  31   a  of the laser scanning device  30 . The compressed air supply unit  110  is configured such that the compressed air supply unit  110  can compress air using a force applied to the image forming apparatus  100  by a user without using an additional driving source. 
     As shown in  FIG. 3 , the compressed air supply unit  110  includes a cylinder  120  having an air compression part  121  as a space in which air is compressed and a piston  130  mounted in the air compression part  121  of the cylinder  120  to compress air. The cylinder  120  has a cylinder body  122  with air discharge ports  122   a  and an air suction port  122   b . The air discharge ports  122   a  are provided at one end of the cylinder body  122 , and the air suction port  122   b  is arranged adjacent to the air discharge ports  122   a . Although  FIG. 3  shows that the cylinder body  122  is provided with two air discharge ports  122   a  and one air suction port  122   b , the number of the air discharge ports  122   a  and the air suction port  122   b  can be changed as needed by the design of the image forming apparatus  100 . 
     A shutter  123  is mounted in the air compression part  121  of the cylinder  120  to open and close the air suction port  122   b . One end of the shutter  123  is fixed to the cylinder body  122 , and the shutter  123  pivots on the fixed end to open and close the air suction port  122   b . When the piston  130  moves in an “A” direction shown in  FIG. 3 , a suction force is applied to the air suction port  122   b . The shutter  123  pivots away from the air suction port  122   b  by the suction force, and opens the air suction port  122   b . On the other hand, when the piston  130  moves in a “B” direction of  FIG. 3 , the air sucked into the air compression part  121  is compressed. The shutter  123  is pushed against the air suction port  122   b  by an inner pressure of the air compression part  121 , and closes the air suction port  122   b.    
     The piston  130  has a piston rod  131  having a first end that moves in the air compression part  121  of the cylinder  120  and a second end that extends to the outside of the cylinder  120 . The first end portion of the piston rod  131  is provided with a press member  132  to apply a pressure to the air when the piston rod  131  moves. An outer peripheral surface of the press member  132  is in contact with an inner peripheral surface of the cylinder  120  so that the press member  132  can compress the air during the reciprocating movement of the piston rod  131 . 
     As shown in  FIG. 4 , the cylinder  120  is hingedly coupled to the main body frame  10   a , and the piston  130  is hingedly coupled to the cover  11 . The cylinder  120  has a frame coupling part  124 , and the main body frame  10   a  has a first coupling pin  12  fitted through the frame coupling part  124  of the cylinder  120 . The cylinder  120  can be hingedly coupled to the main body frame  10   a  by fitting the first coupling pin  12  through the frame coupling part  124  and coupling a fixing member  1 , such as a nut, to an end of the first coupling pin  12 . 
     The cover  11  has a piston coupling part  11   a  protruding toward the piston  130 . The second end of the piston rod  131  is provided with a cover coupling part  131   a  that is pin-coupled to the piston coupling part  11   a  of the cover  11 . The piston  130  can be hingedly coupled to the cover  11  by fitting a second coupling pin  13  through the coupling parts  11   a  and  131   a  and coupling a fixing member  2 , such as a nut, to an end of the second coupling pin  13 . However, the piston  130  need not be coupled to the cover  11  in all aspects, such as where the piston  130  is driven by hand or by another movable part within the image forming apparatus  100 . 
     As shown in  FIGS. 2 and 3 , the cleaning device includes at least one connecting pipe  140  to guide the compressed air from the compressed air supply unit  110  to the laser scanning device  30 , and a spray member  150  to evenly spray the compressed air supplied from the compressed air supply unit  110  to the light transmitting member  31   a.    
     The spray member  150  is mounted adjacent to the light transmitting member  31   a . The spray member  150  includes a spray hole  151  to spray the compressed air to the light transmitting member  31   a , and connecting parts  152  to connect to the connecting pipes  140 . The connecting parts  152  are arranged along a longitudinal direction of the spray member  150 . As shown in  FIG. 2 , two connecting parts are provided at the spray member  150 . The spray hole  151  may be inclined toward the light transmitting member  31   a  and may have a slit shape extending in a longitudinal direction of the light transmitting member  31   a.    
     As shown in  FIG. 3 , the spray member  150  may be provided with a valve member  153  to open and close the spray hole  151 . For convenience, the illustration of the valve member is omitted in  FIG. 2 . A first end of the valve member  153  is fixed to the spray member  150 , and a second end of the valve member  153  pivots on the first end to open and close the spray hole  151 . When the piston  130  moves in the “A” direction of  FIG. 3 , a suction force is applied to the spray hole  151 . The valve member  153  contacts the spray member  150  by the suction force, and closes the spray hole  151 . When the spray hole  151  is closed when air is sucked into the cylinder  120  as described above, the interior of the cylinder  120  can be prevented from being contaminated with paper dust or toner powder sucked into the cylinder  120 . On the other hand, when the piston  130  moves in the “B” direction of  FIG. 3 , the valve member  153  pivots away from the spray hole  151  by an air pressure applied from the cylinder  120  to the spray member  150 , and opens the spray hole  151 . 
     One end of the connecting pipe  140  communicates with the air discharge port  122   a  of the cylinder  120 . The other end of the connecting pipe  140  is connected to the connecting part  152  of the spray member  150 . The connecting pipe  140  may be made of a flexible material. Even when the image forming apparatus  100  has a small inner space, the flexible connecting pipe  140  can be bent so as not to interfere with components of the image forming apparatus  100  arranged between the compressed air supply unit  110  and the laser scanning device  30 . 
     The operation of the cleaning device according to an embodiment of the present invention will be described with reference to  FIGS. 1 ,  3  and  5 .  FIG. 5  shows a state in which the cover is opened in the image forming apparatus shown in  FIG. 1 . When intending to remove the jammed paper from the image forming apparatus  100  or replace components of the image forming apparatus, such as the developing device  40 , the user pulls the cover  11  to open a portion of the main body  10 , as shown in  FIG. 5 . Occasionally, although the image forming apparatus  100  has no error, a user can open the cover  11  to clean the light transmitting member  31   a.    
     When the cover  11  moves relative to the main body frame  10   a  as shown in  FIG. 5 , the piston  130  of the compressed air supply unit  110  coupled to the cover  11  moves in the “A” direction, and accordingly air is sucked into the air compression part  121  of the cylinder  120  through the air suction port  122   b  (refer to  FIG. 3 ). When the user closes the cover  11  as shown in  FIG. 1 , the piston  130  of the compressed air supply unit  110  moves in the “B” direction, and compresses the air. The compressed air is discharged through the air discharge ports  122   a , and is guided to the spray member  150  along the connecting pipes  140 . The compressed air introduced into the spray member  150  is distributed adequately in the spray member  150 , and is sprayed to the light transmitting member  31   a  through the spray hole  151 , thereby removing foreign substances attached to the light transmitting member  31   a  (refer to  FIG. 3 ). While not required, a filter can be included at the port  122   b  and/or the ports  122   a  to prevent the introduction of foreign elements by the cleaning member. 
       FIG. 6  shows a modified example of the mounting position and structure of the compressed air supply unit in the present invention, according to another embodiment of the present invention.  FIG. 7  shows the constitution of the compressed air supply unit shown in  FIG. 6 . 
     As shown in  FIGS. 6 and 7 , a compressed air supply unit  160  according to this embodiment may be mounted near a rotational center  11   b  of the cover  11  and the laser scanning device  30 . If the compressed air supply unit  160  is mounted near the rotational center  11   b  of the cover  11 , although a pivot angle of the cover  11  is set to be large, the compressed air supply unit  160  can be fabricated compactly. If the compressed air supply unit  160  is mounted near the laser scanning device  30 , since the connecting pipes  140  connecting the compressed air supply unit  160  and the laser scanning device  30  can be shortened, the interference of the connecting pipes  140  with the peripheral components can be minimized. 
     A cylinder  170  of the compressed air supply unit  160  according to this embodiment is fixedly mounted in the main body  10 , and an end of a piston  180  is connected to the cover  11 . If the end of the piston  180  is fixed to the cover  11 , a piston rod  181  may be formed in an arc shape as shown in  FIG. 7 , based on a rotational trajectory of the cover  11 . Accordingly, an air compression part  171  of the cylinder  170 , as a space in which the piston rod  181  moves, is also formed in an arc shape corresponding to the piston rod  181 . 
     If the compressed air supply unit  160  is mounted as described above, when the cover  11  is opened, the piston rod  181  moves in an “A” direction of  FIG. 7 , and air is sucked into the air compression part  171  of the cylinder  170 . When the cover  11  is closed, the piston rod  181  moves in a “B” direction of  FIG. 7  to compress the air in the air compression part  171 , and the compressed air is sprayed to the laser scanning device  30 . 
       FIG. 8  shows a modified example of compressing air by the compressed air supply unit interlocking with components other than the cover  11 , according to yet another embodiment of the present invention. In the following description, only the structural and operational features of this embodiment are explained, and the same elements as shown in  FIGS. 1 to 5  are denoted by the same reference numerals. 
     A compressed air supply unit  110  of this embodiment is configured such that the compressed air supply unit  110  can compress air by interlocking with the movement of the paper feeding cassette  21  removably mounted to the main body frame  10   a . As shown in  FIG. 8 , a piston  130   a  of the compressed air supply unit  110  is fixed to the paper feeding cassette  21 , and a cylinder  120   a  is fixed to the main body frame  10   a . When the user pulls out the paper feeding cassette  21  to insert additional printable media, the piston  130   a  moves with the paper feeding cassette  21  in an “A” direction, and accordingly air is sucked into the cylinder  120   a  through the air suction port  122   b . When the user pushes in the paper feeding cassette  21 , the piston  130   a  moves in a “B” direction and compresses the air in the cylinder  120   a . The compressed air is discharged through the connecting pipes  140 , and cleans the light transmitting member  31   a  (refer to  FIG. 3 ) of the laser scanning device. 
     In the above description, the light transmitting member  31   a  of the laser scanning device  30  has been exemplified as an object to be cleaned by the cleaning device; however, the present invention is not restricted thereto. Aspects of the present invention can also be applied to cleaning for other objects to be cleaned, such as a roller, in the image forming apparatus. 
     As apparent from the above description, the image forming apparatus according to aspects of the present invention can clean the inner components of the image forming apparatus by compressing air without an additional driving source. 
     Further, since the cleaning operation is performed simultaneously when a user removes a paper jam, replaces a component of the image forming apparatus, supplies additional printable media, or accesses the interior of the image forming apparatus for another reason, the user does not need to perform an additional component cleaning operation. Accordingly, convenience in use is enhanced. Still further, the cleaning device according to aspects of the present invention can effectively clean an object to be cleaned without installing complicated structures around the object. 
     Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.