Image forming apparatus having a compact size

An image forming apparatus having a compact size includes a printing medium supplying unit to hold printing media and to supply a printing medium, an image forming unit disposed above the printing medium supplying unit to form images on a printing medium, and a printing medium feeding part substantially formed in a letter “C” shape, having a part which extends to the image forming unit and which is inclined in a downward direction along a printing medium moving direction to feed the printing medium from the printing medium supplying unit to the image forming unit.

BACKGROUND

Aspects of the present invention relate to an image forming apparatus. More particularly, aspects of the present invention relate to an arrangement of parts of an image forming apparatus which causes the image forming apparatus to have a compact size.

2. Description of the Related Art

Generally, image forming apparatuses, (especially electro photographic image forming apparatuses such as laser printers), include a printing medium supplying unit that holds printing media (such as sheets of paper), picks up the printing media one by one, and supplies the picked up printing medium; a feeding roller that supplies the printing medium picked up from the printing medium supplying unit; an image forming unit that forms images corresponding to printing data on the printing medium fed by the feeding roller, a fixing unit that fixes the images formed onto the printing medium by the image forming unit; and a discharging unit that discharges the printing medium as the printing medium passes through the fixing unit to the outside thereof.

The conventional image forming apparatuses including above-described parts may be classified into two types which have different basic structures according to an arrangement of parts thereof: an “S” type and a “C” type. The “S” type is an image forming apparatus that has a printing medium moving path which is similar to the shape of the letter “S.” The “C” type is an image forming apparatus that has a printing medium moving path which is similar to the shape of the letter “C”.

FIG. 1shows an “S” type conventional image forming apparatus10. Referring toFIG. 1, a printing medium supplying unit11is disposed at a low vertical position of the image forming apparatus10. A feeding roller13, an image forming unit15, and a fixing unit17are disposed in a row above the printing medium supplying unit11. According to this structure, the feeding roller13, the image forming unit15, and the fixing unit17are disposed in such a way that the positions at which a printing medium passes through each of the feeding roller13, the image forming unit15, and the fixing unit17are at approximately the same horizontal level. Alternatively, the feeding roller13, the image forming unit15, and the fixing unit17are disposed in such a way that the positions at which a printing medium passes through are slightly upwardly inclined from the feeding roller13to the fixing unit17.

The exposure unit16irradiates laser beams corresponding to printing data onto a photosensitive medium15aof the image forming unit15. The exposure unit16is disposed above the image forming unit15. A feed guiding part12is disposed between the printing medium supplying unit11and the feeding roller13to divert a printing medium from its feeding direction, so that the printing medium picked up at the printing medium supplying unit11is fed to the feeding roller13. An auxiliary printing medium supplying unit14is disposed at a side of the feeding roller13to feed special kinds of printing medium, such as envelopes, into the image forming apparatus10.

A discharging unit18is disposed above the fixing unit17. Printing media discharged from the discharging unit18are piled up at a printing medium storing part19disposed above the exposure unit16. Also, a discharge guiding part18ais disposed between the discharging unit18and the fixing unit17to divert a printing medium from its feeding direction, so that the printing medium which passes through the fixing unit17is fed to the discharging unit18.

Therefore, the printing medium supplying unit11picks up printing media one by one, and the feed guiding part12diverts each of the printing media from its feeding direction to feed the printing media to the feeding roller13. The feeding roller13feeds the printing medium to the image forming unit15. At this time, the exposure unit16forms electrostatic latent images corresponding to printing data on the photosensitive medium15aof the image forming unit15, and the image forming unit15develops the electrostatic latent images into images using toner.

The images formed on the photosensitive medium15aof the image forming unit15are transferred onto a printing medium as the feeding roller13moves the printing medium between the photosensitive medium15aand the transferring roller15b. When the printing medium with the transferred images passes through the fixing unit17, the images are fixed onto the printing medium. Then, the printing medium with the fixed images moves along the discharge guiding part18ato the discharging unit18. The printing medium is discharged onto the printing medium storing part19disposed above the exposure unit16and the image forming unit15, and the printing work is completed.

However, because a printing medium has to change a feeding direction twice during the printing work, it is difficult to design an “S” type image forming apparatus10which has a structure having a lower height and a shorter length. Also, it is difficult to design an “S” type image forming apparatus10which has a compact size because there are some dead spaces that cannot be used, such as a first space21between the feeding roller13and the printing medium storing part19, and a second space22between the exposure unit16and the fixing unit17, as illustrated inFIG. 1.

Referring toFIG. 2, a “C” type conventional image forming apparatus30includes a printing medium supplying unit31disposed at a low position therein. A feeding roller33, an image forming unit35, and a fixing unit37are vertically disposed in a row above the printing medium supplying unit31. An auxiliary printing medium supplying unit (not shown) may be disposed above the printing medium supplying unit31to feed special kinds of printing media, such as envelopes, into the image forming apparatus30. A discharging unit38is disposed above the fixing unit37, and discharges printing media to a printing medium storing part39disposed above the image forming unit35. An exposure unit36is disposed at a side of the image forming unit35to form electrostatic latent images on a photosensitive medium35a.

Therefore, the printing medium supplying unit31picks up printing media loaded therein one by one and feeds the sheets of printing media to the feeding roller33. The feeding roller33feeds each of the printing media to the image forming unit35. At this time, the exposure unit36forms electrostatic latent images corresponding to printing data on the photosensitive medium35aof the image forming unit35, and the image forming unit35develops the electrostatic latent images into images using toner. The transferring roller35btransfers the images formed on the photosensitive medium35aof the image forming unit35onto a printing medium passing between the photosensitive medium35aand the transferring roller35b. While the printing medium with the transferred images passes through the fixing unit37, the images are fixed onto the printing medium. The discharging unit38discharges the printing medium with the fixed images to the printing medium storing part39, and the printing work is completed.

Because a printing medium has to change its feeding direction only once during the printing work, the “C” type image forming apparatus30may be designed to have a shorter length than the length of the “S” type image forming apparatus10. However, because the printing medium supplying unit31, the image forming unit35, the fixing unit37, and the discharging unit38are vertically disposed in a line, the “C” type image forming apparatus30has a higher height. Also, it is difficult to design a “C” type image forming apparatus30which has a compact size because there are some dead spaces that cannot be used, such as a third space41between the printing medium supplying unit31and the exposure unit36, and a fourth space42between the exposure unit36and the printing medium storing unit39, as illustrated inFIG. 2.

Furthermore, in each of the conventional “S” type and “C” type image forming apparatuses10and30, printing media are discharged to the printing medium storing parts19and39formed at top surfaces of the image forming apparatuses10and30, respectively, so that the image forming apparatuses10and30should have printing medium supporting plates19aand39a, respectively, to prevent the discharged printing medium from falling to the floor. The use of these printing medium supporting plates19aand39aincreases the number of parts of the image forming apparatuses10and30.

Also, because a printing medium is discharged through a top surface of the image forming apparatuses10and30, users cannot use a space above the top surface of the image forming apparatus10and30, which is also a problem.

SUMMARY

Aspects of the present invention have been developed in order to overcome the above and/or other drawbacks and/or other problems associated with the conventional arrangement of image forming apparatuses. An aspect of the present invention provides an image forming apparatus having a more compact size than the conventional image forming apparatus.

Also, another aspect of the present invention provides an image forming apparatus that discharges a printing medium through a side thereof so that a space above a top surface thereof can be used.

The above aspects and/or other features of the present invention can substantially be achieved with an image forming apparatus which includes a printing medium supplying unit to hold and supply printing media, an image forming unit disposed above the printing medium supplying unit to form images on one of the printing media supplied from the printing medium supplying unit, and a printing medium feeding part substantially formed in a letter “C” shape, having a part which extends to the image forming unit and which is inclined in a downward direction along a printing medium moving direction to feed the printing medium from the printing medium supplying unit to the image forming unit in the downward direction towards the printing medium supplying unit.

The image forming apparatus according to an aspect further includes a case holding the printing medium supplying unit, the image forming unit, and the printing medium feeding part, and an auxiliary printing medium supplying unit disposed between a top surface of the case and a top end of the printing medium feeding part to supply another printing medium to the image forming unit.

The image forming apparatus according to an aspect may further include a discharging unit disposed above the printing medium supplying unit to discharge the one printing medium through a side of the case.

Also, the image forming apparatus according to an aspect may further include a printing medium supporting part disposed between the discharging unit and the side of the case to support the printing medium and the second printing medium discharged from the discharging unit. The printing medium supporting part may be inclined downward along a printing medium discharging direction so as to support the one printing medium on an incline.

According to another aspect of the present invention, an image forming apparatus includes a case, a printing medium supplying unit disposed at a lower portion of the case to hold and supply printing media, an image forming unit disposed above the printing medium supplying unit within the case to form images on one of the printing media, a printing medium feeding part within the case having a feeding roller to feed the printing medium from the printing medium supplying unit to the image forming unit and a printing medium feeding path that connects the feeding roller with the image forming unit and which is inclined in a downward direction to feed the one printing medium down to the image forming unit, a fixing unit within the case to fix images formed by the image forming unit onto the printing medium, a discharging unit to discharge the printing medium with the fixed images outside of the case, and a controller to control the printing medium supplying unit, the image forming unit, the feeding roller, the fixing unit, and the discharging unit in order to perform printing operations.

The image forming apparatus according to another aspect may further include an auxiliary printing medium supplying unit disposed between a top surface of the case and the feeding roller to supply another printing medium to the image forming unit.

According to another aspect, the auxiliary printing medium supplying unit may include a printing medium entrance formed at a back area of the top surface of the case and a door to selectively open or close the printing medium entrance.

According to another aspect, the image forming unit may be disposed so that a height from a bottom surface of the case to a part of the image forming unit at which images are transferred onto the one printing medium is lower than a height from the bottom surface of the case to a top end of the feeding roller.

According to another aspect, a top surface of the case is formed in a plane substantially parallel to a bottom surface of the case, and the height from the bottom surface of the case to the top surface of the case is approximately 150 mm or less.

According to another aspect, the discharging unit is disposed above the printing medium supplying unit at a side of the fixing unit to discharge the printing medium through the side of the case.

According to another aspect, the image forming apparatus may further include a printing medium supporting part formed between the discharging unit and the side of the case to support the one printing medium discharged from the discharging unit.

According to another aspect, the printing medium supporting part may be inclined in a downward direction along a printing medium discharging direction so as to support the one printing medium on an incline.

According to another aspect, the fixing unit may be disposed so that a height from a bottom surface of the case to a part of the fixing unit at which a printing medium passes through is substantially the same height as a height from the bottom surface of the case to a part of the image forming unit at which images are transferred onto the printing medium.

According to another aspect, the discharging unit may be disposed so that a height from a bottom surface of the case to a part of the discharging unit through which a printing medium passes is higher than a height from the bottom surface of the case to a part of the fixing unit through which the printing medium passes.

The controller according to an aspect of the invention may be disposed above the discharging unit near a side of the case through which the printing medium is discharged.

DETAILED DESCRIPTION

Referring toFIG. 3, an image forming apparatus100according to an embodiment of the present invention includes a case110, a printing medium supplying unit120, a printing medium feeding part130, an image forming unit140, a fixing unit170, a discharging unit180, and a controller190. It is understood that other components may be used instead of or in addition to the components shown inFIG. 3and described above.

The case110forms the outside of the image forming apparatus100, and encases a printing medium supplying unit120, an image forming unit140, a printing medium feeding part130, a fixing unit170, a discharging unit180, and a controller190, for support and protection. The case110has a top surface111formed in a plane substantially parallel to a bottom surface117. It is understood the top surface111is not required to be formed substantially parallel to the bottom surface117, and may instead be curved or designed in numerous other ways. The top surface111may also be formed to have indentations for holding various items, such as, for example, sheets of paper.

The printing medium supplying unit120is disposed at a lower portion of the case110. The printing medium supplying unit120holds predetermined sheets of printing media (such as paper, transparency sheets, etc.), and picks up each sheet one by one to feed the sheet to the printing medium feeding part130. The printing medium supplying unit120includes a printing medium cassette123to hold printing media and a pickup roller121disposed above the printing medium cassette123to pick the sheets up from the printing medium cassette123.

The image forming unit140is disposed above the printing medium supplying unit120, and forms images on a printing medium. The image forming unit140includes a photosensitive medium141on which an exposure unit150irradiates laser beams to form electrostatic latent images, a developing roller143to develop the electrostatic latent images on the photosensitive medium141using toner, and a transferring roller145disposed to be in contact with the photosensitive medium141. When a printing medium fed from the printing medium supplying unit120passes between the photosensitive medium141and the transferring roller145, images formed on the photosensitive medium141are transferred onto the printing medium.

The printing medium feeding part130is disposed between the printing medium supplying unit120and the image forming unit140, and feeds a printing medium picked up by the pickup roller121of the printing medium supplying unit120to the image forming unit140. The printing medium feeding part130is formed substantially in the shape of the letter “C”. A part of the printing medium feeding part130which extends to the image forming unit140is inclined in a downward direction along a printing medium moving direction. The shown printing medium feeding part130includes a printing medium reversing path131and a printing medium feeding path133that extends from a front end of the printing medium reversing path131and is inclined in a downward direction along the printing medium moving direction. However, it is understood that the printing medium feeding part130need not include the printing medium reversing path131and/or the printing medium feeding path133in all aspects of the invention.

A pair of transporting rollers132is preferably, but not necessarily, disposed at approximately the middle of the printing medium reversing path131to transport a printing medium picked up by the pickup roller121. It is understood that one or more than two transporting rollers may be used instead of the pair of transporting rollers132, and that these transporting rollers may be disposed in various positions other than the position shown inFIG. 3. A printing medium detecting sensor138is disposed between the pickup roller121and a pair of transporting rollers132to detect a printing medium. A feeding roller135is disposed at the location where the printing medium reversing path131is connected to the printing medium feeding path133, and feeds a printing medium to the image forming unit140.

The printing medium feeding path133, through which a printing medium moves from the feeding roller135to the photosensitive medium141of the image forming unit140, is inclined in a downward direction relative to the printing medium moving direction, so that a mounting height of the image forming unit140is lower than the mounting height of the exposure units16and36shown inFIGS. 1 and 2, respectively. In other words, since the printing medium feeding path133is formed to incline in a downward direction relative to the printing medium moving direction, the image forming unit140is disposed inside the case110in such a way that a height of a part140aof the image forming unit140where images are transferred onto a printing medium is lower than a height of a top end of the feeding roller135.

The part140aof the image forming unit140where images are transferred onto a printing medium is a contacting part disposed between the photosensitive medium141and the transferring roller145. Therefore, the contacting part140ais located at a lower position than a contacting part135adisposed between the feeding roller135and a feeding backup roller136. By lowering the mounting height of the image forming unit140, the height H3 of the image forming apparatus100is lowered.

In an image forming apparatus100according to an embodiment of the present invention, when the height H1 from the bottom surface117to the contacting part135adisposed between the feeding roller135and the feeding backup roller136is set to be approximately 90 mm, the height H2 from the bottom surface117to the contacting part140abetween the photosensitive medium141and the transferring roller145is preferably set to be approximately 60 mm. However, it is understood that the heights H1 and H2 are not required to be adjusted to 90 mm and 60 mm, respectively, and are not required to be set to a 3:2 ratio, respectively.

Conventionally, in order to lower a height H3 of an image forming apparatus100, designers have tried to lower a height of the printing medium feeding part130which feeds a printing medium from the printing medium supplying unit120to the image forming unit140. In other words, designers have tried to decrease a curvature radius of the printing medium reversing path131of the printing medium feeding part130formed in a curved line like a letter “C”, thereby lowering the height H3 of the image forming apparatus100. However, when a curvature radius of the printing medium reversing path131is decreased too much, various problems occur. For example, a printing medium gets easily jammed, feeding a printing medium generates a loud noise, and a printing medium gets damaged during feeding. To prevent these problems from occurring, the printing medium reversing path131must have a curvature radius larger than a predetermined curvature radius. As a result, using the conventional method to lower a height of an image forming apparatus produces very limited results.

However, as described above, in an image forming apparatus100according to an embodiment, a curvature radius of the printing medium reversing path131, and more specifically, a height of the printing medium reversing path131, is substantially the same as the height of the printing medium reversing path131used in the conventional image forming apparatus10or30. Additionally, the printing medium feeding path133, which is connected to the printing medium reversing path131through which a printing medium moves to the image forming unit140after being reversed, is inclined in a downward direction along a printing medium moving direction. As a result, the image forming apparatus100according to an embodiment can prevent above-described problems from occurring, and can lower the height H3 of the image forming apparatus100.

The exposure unit150is disposed above the image forming unit140to irradiate laser beams corresponding to printing data so as to form electrostatic latent images on the photosensitive medium141. The printing medium supplying unit120, the image forming unit140, and the exposure unit150are vertically arranged above the bottom surface117of the case110. When a height H1 from the bottom surface117to the contacting part135aof the feeding roller135is approximately 90 mm, a height H3 from the bottom surface117to the top surface111of the case110is approximately 150 mm or less. However, it is understood that H1 and H3 are not limited to being 90 mm and 150 mm, respectively, and are not required to be set to a 3:5 ratio, respectively.

The fixing unit170is disposed at a side of the image forming unit140above the printing medium supplying unit120. The fixing unit170fixes images, which are transferred onto a printing medium when the printing medium passes through the image forming unit140, using high temperature and high pressure. The fixing unit170includes a pressure roller172to press a printing medium and a heating roller171to generate a high temperature.

According to an aspect of the invention, the fixing unit170is preferably disposed in the case110in such a way that a height of a contacting part170adisposed between the pressure roller172and the heating roller171where a printing medium passes through the fixing unit170is substantially the same as the height of the contacting part140adisposed between the photosensitive medium141and the transferring roller145of the image forming unit140. A fixing feeding path160through which a printing medium moves from the image forming unit140to the fixing unit170is shown formed in a concave shape, as illustrated inFIG. 3. Therefore, a printing medium moves in a downward direction from the feeding roller135to the image forming unit140, and then moves in an upward direction while passing along the fixing feeding path160. It is understood that the contacting parts170aand140aare not required to be disposed at substantially the same height. It is further understood that the fixing feeding path160is not necessarily required to be concave, and may instead take other shapes, such as, for example, a flat horizontal shape.

The discharging unit180is disposed at a side of the fixing unit170above the printing medium supplying unit120, and discharges a printing medium with fixed images passing through the fixing unit170to the outside of the image forming apparatus100through a side113of the case110. Hereinafter, a side113(namely, a right side inFIG. 3) of the case110through which a printing medium is discharged is referred to as a front surface of the case110, and an opposite side115(namely, a left side inFIG. 3) of the case110is referred as a back surface of the case110.

The shown discharging unit180is configured to include a plurality of discharging rollers181. The discharging unit180is shown disposed in such a way that a part180aof the discharging unit180through which a printing medium passes is located at substantially the same height as the part170aof the fixing unit170through which a printing medium passes through. The discharging unit180is disposed in such a way that a height of the part180aof the discharging unit180through which a printing medium passes is higher than the height of the part170aof the fixing unit170. The reason why it is preferable to mount the part180aat a higher height than the part170ais because mounting the discharging unit180at a higher level allows a large amount of discharged printing media to be piled up. However, it is understood that the part180amay also be mounted at a lower height than the part170a, in which case a lower level of discharged printing media can be piled up.

The discharging unit180is shown disposed near the front surface113of the case110so that printing media are directly discharged to the outside of the case110. Preferably, the discharging unit180is disposed at a predetermined distance from the front surface113inside of the case110, and a printing medium supporting part183is disposed between the discharging unit180and the front surface113of the case110to receive printing media187discharged by the discharging unit180. A discharging space185where a predetermined sheet of printing media discharged from the discharging unit180can be piled up is formed above the printing medium supporting part183. The discharging space185is preferably formed as a recess, such as a concave shape, in the front surface113of the case110. The discharging space185allows some of the space above the printing medium supplying unit120to be used for receiving discharged printing media, thus providing a compact image forming apparatus100.

The printing medium supporting part183is shown formed integrally with the case110, as illustrated inFIG. 3. Alternatively, although not illustrated, the printing medium supporting part183may be formed as a separate part which attaches and detaches to and from the front side113of the case110. The printing medium supporting part183may be used when a resting surface101, such as a top surface of a desk where the image forming apparatus100is set up, does not have enough space to receive printing media187discharged from the image forming apparatus100.

The printing medium supporting part183may be disposed to be inclined in an upward or downward direction with respect to the printing medium discharging direction, or may be disposed parallel to the resting surface101. As illustrated inFIG. 3, when the printing medium supporting part183is inclined in a downward direction with respect to the printing medium discharging direction, a printing medium discharged by the discharging unit180moves in a stable fashion along the printing medium supporting part183, and is thus piled up in a stable fashion on the resting surface101, such as a desk, where the image forming apparatus100is set up. In other words, a space on the resting surface101, such as a top surface of a desk, where the image forming apparatus100is set up can be used as a space for piling up discharged printing media.

The controller190controls the printing medium supplying unit120, the image forming unit140, the feeding roller135, the fixing unit170, and the discharging unit180to control printing operations. The controller190is shown disposed above the discharging unit180and the printing medium supporting part183. The controller190includes a circuit board191for controlling printing operations, an operation display part193(seeFIG. 4) for displaying a printing status, a power switch192for turning on and off power supplied to the image forming apparatus100, and control buttons195(seeFIG. 4) for users to control the image forming apparatus100. However, it is understood that the controller190can be otherwise located.

In the shown embodiment, the circuit board191is disposed above the discharging unit180and the discharging space185to maximize the use of an inner space of the case110. Since the circuit board191is disposed near the front surface113of the case110according to the arrangement of an embodiment, the circuit board191is located close to the operation display part193, the power switch192, and the control buttons195, which are each shown disposed on the front surface113of the case110. Therefore, it is not required to fix each of the operation display part193, the power switch192, and the control buttons195to the case110, and then to connect each of these components to the circuit board191using electrical wires. In other words, the operation display part193, the power switch192, and the control buttons195may all be directly disposed on the circuit board191.

As a result, fixing the circuit board191to the case110will also fix the operation display part193, the power switch192, and the control buttons195on the case110. Therefore, the image forming apparatus100according to an embodiment does not require separate parts to fix each of the operation display part193, the power switch192, and the control buttons195to the case110, decreasing the cost of materials and assembly. It is understood, however, that the operation display part193, the power switch192, and the control buttons195are not required to be fixed to the circuit board191, and that these components may each be installed separately to the case110, or some components may be fixed to the circuit board191and other components may be separately installed to the case110.

The operation display part193, the power switch192, and the control buttons195are preferably arranged at the front surface113of the case110, as illustrated inFIG. 4. Alternatively, the operation display part193, the power switch192, and the control buttons195may be arranged at a front area of the top surface111of the case110, as illustrated inFIG. 5. It is understood that the controller190may be connected to an electronic device, such as a computer or a digital camera, via a network or wirelessly.

An image forming apparatus100according to an embodiment of the present invention may further include an auxiliary printing medium supplying unit200for supplying special kinds of printing media, such as an envelope, a thick printing medium, etc., into the image forming apparatus100. It is understood that regular printing media may also be supplied into the image forming apparatus100by the auxiliary printing medium supplying unit200. The auxiliary printing medium supplying unit200is preferably disposed between the top surface111of the case110and a top end of the printing medium feeding part130, although may be disposed in other locations as well, such as off to a side of the case110.

According to an embodiment, the feeding roller135is disposed at the top end of the printing medium feeding part130so that the auxiliary printing medium supplying unit200is disposed between the top surface111of the case110and the feeding roller135. A printing medium entrance201of the auxiliary printing medium supplying unit200is formed at a back area of the top surface111of the case110. Since the printing medium entrance201according to an embodiment is formed at the top surface111of the case110, users can supply printing media, including special kinds of printing media, in a downward direction. Therefore, it is easy to supply printing media into the image forming apparatus100using the auxiliary printing medium supplying unit200.

The auxiliary printing medium supplying unit200may further include an auxiliary printing medium detecting sensor203. When the auxiliary printing medium detecting sensor203detects a printing medium, the controller190rotates the feeding roller135to feed the printing medium entering the auxiliary printing medium supplying unit200to the image forming unit140.

Furthermore, the auxiliary printing medium supplying unit200may include a door202to selectively open or close the printing medium entrance201. To supply a printing medium into the auxiliary printing medium supplying unit200, users open the door202to supply a printing medium through the printing medium entrance201. When the auxiliary printing medium supplying unit200is not in use, users can close the door202to prevent foreign materials, such as dust, from entering the case110through the printing medium entrance201. The door202may be fixed by a hinge so that users can easily open or close the door202by hand, although the door202may also be controlled automatically, for example, by the controller190. It is understood that the door202may be fixed to the case110with various types of fasteners other than a hinge.

Hereinafter, an operation of an image forming apparatus100according to an embodiment of the present invention will be described with reference toFIGS. 3 and 4. Upon receiving a printing order from a host (not shown), such as a computer connected to the image forming apparatus100, the controller190operates the pickup roller121to pick up a printing medium loaded into the printing medium supplying unit120and to feed the printing medium to the feeding roller135. When the printing medium detecting sensor138is triggered by the picked up printing medium, the controller190operates the transporting roller132and the feeding roller135to feed the printing medium to the image forming unit140.

The controller190controls the exposure unit150to irradiate laser beams corresponding to printing data onto the photosensitive medium141of the image forming unit140. The electrostatic latent images corresponding to printing data received from the host are formed on the photosensitive medium141.

When the photosensitive medium141rotates, toner supplied by the developing roller143develops the electrostatic latent images into toner images. The toner images on the photosensitive medium141are transferred onto a printing medium which is fed by the feeding roller135to pass between the photosensitive medium141and the transferring roller145.

The printing medium having the transferred images continues to move to the fixing unit170. When the printing medium moves to the fixing unit170, it passes between the pressure roller172and the heating roller171. At this time, the transferred images are fixed on the printing medium by the high pressure generated by the pressure roller172and the high temperature generated by the heating roller171.

The printing medium having the fixed images is discharged through the front surface113of the image forming apparatus100by the discharging unit180. The discharged printing medium moves in a stable fashion along the printing medium supporting part183disposed in front of the discharging unit180. Finally, the printing medium187piles up on the printing medium supporting part183of the image forming apparatus100and the resting surface101, as illustrated inFIG. 3.

In an image forming apparatus100according to an embodiment of the present invention, since the printing medium reversing path131is substantially formed in the shape of the letter “C” and the printing medium feeding path133expended from the feeding roller135is configured to be inclined in a downward direction in relation to the print medium moving direction, the image forming unit140and the fixing unit170are located lower than the feeding roller135. Arranging the printing medium feeding part130, the image forming unit140, and the fixing unit170according to aspects described above minimizes unused spaces inside the image forming apparatus100, such as, for example, the first, second, third, and fourth spaces21,22,41and42inside the conventional image forming apparatus10and30as illustrated inFIGS. 1 and 2.

By minimizing these unused spaces21,22,41, and42, the image forming apparatus100according to an embodiment has a height much lower than the height of the conventional image forming apparatus10and30. Therefore, an image forming apparatus100according to aspects of the present invention has a more compact and slim size than the sizes of the conventional image forming apparatuses10and30.

Furthermore, since the image forming apparatus100according to aspects of the present invention discharges a printing medium through the front surface113of the case110, the top surface111of the case110may be formed in a plane substantially parallel to the bottom surface117thereof. Therefore, users can use a space above the top surface111of the case110for their own convenience. For example, users may put any a small vase, a picture frame, a coffee cup, etc. on the top surface111of the image forming apparatus100. Alternatively, users can put a digital apparatus, such as a laptop computer or a DVD player, on the top surface111of the image forming apparatus100. Users cannot, however, put anything on top surfaces of the cases of the conventional image forming apparatuses10and30.

Moreover, in the image forming apparatus100according to aspects of the present invention, because the image forming unit140is disposed in such a way that a height of a part140aof the image forming unit through which a printing medium passes through is lower than a height of a contacting part135aof a feeding roller135, the image forming apparatus100may be designed to have a lower height than a height of the conventional image forming apparatuses10and30. Therefore, an image forming apparatus100according to aspects of the present invention may have a more compact and slim size than the sizes of the conventional image forming apparatuses10and30.

Also, in an image forming apparatus100according to aspects of the present invention, since a printing medium is discharged through a side113of a case110, space above a printing medium supplying unit120, along with space on a resting area101, such as a top surface of a desk where the image forming apparatus100is set up, can be used as a storing space for receiving discharged printing media. As a result, a separate printing medium supporting plate is not required.

Furthermore, in an image forming apparatus100according to aspects of the present invention, since a top surface111of a case110is a closed surface and formed in a plane, users can freely use a space above the top surface of the case.

Additionally, since an image forming apparatus100according to aspects of the present invention is configured to supply special kinds of printing media, such as envelopes, through a back area of a top surface111of a case110in a downward direction at, users can easily supply special kinds of printing media into the image forming apparatus100.

Furthermore, in an image forming apparatus100according to aspects of the present invention, since a circuit board191of a controller190is disposed near a front surface113of a case110, an operation display part193, a power switch192, and control buttons195, which enable users to control the image forming apparatus100, may be directly mounted on the circuit board191. As a result, additional parts are not required to separately mount the operation display part193, the power switch192, and the control buttons195on the case110and to connect these components to the circuit board191. Therefore, manufacturing and assembly costs of the image forming apparatus100are decreased.

While described in terms of an image forming apparatus, it is understood that the apparatus can further include facsimile, copying, and/or scanning functionality. Additionally, while described in the context of electro photographic image forming apparatuses, it is understood that the invention can be used in other devices.