Title:
PAPER CASSETTE HAVING MANUAL PAPER FEEDER AND IMAGE FORMING APPARATUS INCLUDING THE SAME
Kind Code:
A1


Abstract:
A paper cassette having a manual paper feeder, and an image forming apparatus including the same. The image forming apparatus includes a paper cassette provided with a guide groove formed at a portion of a front surface thereof and having a multi-stepped widths corresponding to multiple width sheets of paper, and a case having a cassette attachment part to insert the paper cassette.



Inventors:
Kim, Young-min (Suwon-si, KR)
Park, Sang-cheol (Suwon-si, KR)
Application Number:
11/457515
Publication Date:
01/17/2008
Filing Date:
07/14/2006
Primary Class:
International Classes:
B65H5/26; B65H3/44
View Patent Images:
Related US Applications:



Primary Examiner:
SANDERS, HOWARD J
Attorney, Agent or Firm:
EIPG (Mclean, VA, US)
Claims:
What is claimed is:

1. An image forming apparatus comprising: a paper cassette including a guide groove formed at a portion of a front surface thereof and having a at least one width portion corresponding to at least one width of a sheet of paper; and a case having a cassette attachment part to insert the paper cassette, wherein a sheet of paper is manually fed through a space defined by the guide groove and the cassette attachment part.

2. The image forming apparatus according to claim 1, wherein the cassette attachment part is formed at a lower part of the case.

3. The image forming apparatus according to claim 1, wherein the guide groove is formed at an upper part of the paper cassette.

4. The image forming apparatus according to claim 1, wherein the guide groove has a multi-stage structure to guide sheets of paper of various widths.

5. The image forming apparatus according to claim 1, wherein the paper cassette comprises a resilient projection formed at an outer surface, and the cassette attachment part of the case comprises a threshold formed at a position spaced apart from the resilient projection, at which the paper cassette is fully inserted into the cassette attachment part, so that the resilient projection becomes stopped by the threshold when the paper cassette is drawn out by a predetermined distance.

6. The image forming apparatus according to claim 1, wherein the cassette attachment part has a paper introduction port formed at a portion corresponding to the guide groove of the paper cassette to manually feed paper.

7. The image forming apparatus according to claim 6, further comprising: guide members installed at the paper introduction port to slide along a width of the paper introduction port.

8. The image forming apparatus according to claim 1, wherein the case comprises a manual feed roller to convey the sheet of paper manually fed through the space defined by the guide groove and the cassette attachment part.

9. A paper cassette usable with an image forming apparatus, the paper cassette comprising: a cassette body having an automatic paper feeder to automatically feed paper into the image forming apparatus; and a manual paper feeder integrally formed with a portion of the cassette body to manually feed paper into the image forming apparatus.

10. The paper cassette according to claim 9, wherein the manual paper feeder comprises a guide groove formed at a portion of a front surface of the cassette body and having a width corresponding to the paper to enable manual feeding of the paper.

11. The paper cassette according to claim 10, wherein the guide groove has a multi-stage structure having different widths corresponding to paper of various widths.

12. The paper cassette according to claim 10, wherein guide members are installed adjacent to the guide groove to be adjusted to the width of the paper.

13. The paper cassette according to claim 10, wherein the cassette body has a paper support surface formed at a portion thereof to function as a support plate to support a bottom surface of the paper manually fed into the guide groove.

14. An image forming apparatus, comprising: a case to contain a paper cassette therein, the case including a cassette attachment part formed at a front part thereof to slidably receive a paper cassette; and a paper cassette comprising: an automatic paper feeder portion to contain paper therein to be automatically fed into the image forming apparatus, and a front wall portion having a grooved portion formed at an upper surface thereof and facing the cassette attachment part to receive paper manually fed therebetween.

15. The image forming apparatus according to claim 14, wherein the cassette attachment part comprises a paper introduction part extending horizontally along an upper portion thereof to receive a paper having a large width to be manually fed.

16. The image forming apparatus according to claim 15, wherein the grooved portion comprises multi-stepped portions extending upwardly and outwardly along the front wall portion to face the paper introduction part, each multi-stepped portion having a different width to receive paper of a corresponding width.

17. The image forming apparatus according to claim 16, wherein the grooved portion is centrally disposed with respect to the front wall portion.

18. The image forming apparatus according to claim 16, further comprising: a pair of guide members slidable along the paper introduction part to provide adjustable guides for papers of any width to be manually fed into the image forming apparatus.

19. The image forming apparatus according to claim 18, further comprising: a lever disposed below the guide groove to pull or push the paper cassette in and out of the cassette attachment part.

20. The image forming apparatus according to claim 19, wherein the front wall portion further comprises: an upper support surface extending along an upper side thereof such that when the paper cassette is pulled out of cassette attachment part by a predetermined amount, the upper support surface provides a support for a bottom of the paper being manually fed between the grooved portion and the paper introduction part.

21. The image forming apparatus according to claim 20, wherein the case comprises a pair of feed rollers to receive and transfer the manually fed paper within the image forming apparatus.

22. The image forming apparatus according to claim 14, wherein the cassette attachment part comprises: an elongated groove at opposite sides thereof to guide the sliding of the paper cassette; and a threshold extending from one inner side of thereof to contact a portion of the paper cassette to limit the drawing out of the paper cassette with respect thereof.

23. The image forming apparatus according to claim 21, wherein the paper cassette comprises a resilient projection to be inserted into the elongated groove to glide therein such that the resilient projection engages with and is stopped by the threshold when slid by a predetermined distance out of the cassette attachment part.

24. An image forming apparatus, comprising: a front surface portion comprising: a cassette attachment part formed therein to receive a paper cassette, and a paper introduction portion formed along a predetermined length of a horizontally extending portion of the cassette attachment part to receive manually fed paper therein; and a paper cassette comprising: a body portion to contain papers to be automatically fed within the image forming apparatus, and a front surface portion including a groove portion formed therein having multi-stepped grooves facing opposite the paper introduction portion to receive corresponding multiple sized manually fed paper therebetween.

Description:

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present general inventive concept relates to an image forming apparatus and, more particularly, to a paper cassette having a manual paper feeder and an image forming apparatus including the same.

2. Description of the Related Art

An image forming apparatus such as a duplicator, a printer, a facsimile, and so on generally has two paper feeding methods, i.e., an automatic paper feeding method of inserting a plurality of sheets of paper into a paper cassette and automatically outputting the paper, and a manual paper feeding method of manually inserting a paper into a manual paper feeder when a sheet of a specific type of paper is fed or several sheets of plain paper are fed one at a time.

FIG. 1 is a perspective view of a conventional image forming apparatus including a manual paper feeder.

Referring to FIG. 1, an image forming apparatus 10 includes a manual paper feeder 20 having a paper insertion slot 22 laterally formed at a case 11 to feed sheets of paper 16 one by one. A cassette attachment part 13 is formed below the paper insertion slot 22 to attach a paper cassette 18 for stacking sheets of paper 16.

Guide members 24 are installed at the paper insertion slot 22 to laterally slide to stably guide various sizes of recording mediums such as an envelope, a label paper, an OHP film, a card sheet, and so on.

Meanwhile, an image forming unit (not shown) for forming an image on the sheet of paper 16 inserted through the paper insertion slot 22 is installed in the image forming apparatus 10. A paper discharge part 19 is formed at an upper end of the image forming apparatus 10 to discharge the sheet of paper 16, on which an image is formed, to an exterior of the image forming apparatus 10.

However, since the conventional image forming apparatus 10 has no support member for supporting a free end of the sheet of paper 16 when the paper is fed through the manual paper feeder 20, the sheet of paper 16 may unstably move sideways while being fed, and the cassette attachment part 13, being in close proximity to the paper insertion slot 22, takes away from the appearance of the image forming apparatus.

In order to solve these problems, Korean Utility Model Registration No. 20-0136727, entitled “Auxiliary Manual Paper Feeding Device for Printer”, discloses a foldable paper support tray installed at a lower part of a manual paper feeding box to function as a guide member. However, this additional guide member increases manufacturing costs.

Meanwhile, since an intermediate part A between the cassette attachment part 13 and the paper insertion slot 22 has a small thickness and a small width, a molding material in which the intermediate part A is formed may not be sufficiently formed of the proper shape or size when a case 11 is injection-molded, thereby causing deformation such as bending of the intermediate part A after injection molding. When the deformed case 11 is used, the guide members 24 cannot smoothly slide along the paper insertion slot 22. In particular, such deformation adversely affects the performance and appearance of the printer. Though reinforcement ribs may be further formed at the intermediate part A, formation of the reinforcement ribs in the limited space decreases injection efficiency and makes the mold structure complex, thereby reducing the lifespan of the mold.

SUMMARY OF THE INVENTION

The present general inventive concept provides an image forming apparatus having a simplified structure as well as improved performance due to removal of an intermediate part between a cassette attachment part and a paper insertion slot.

Additional aspects and advantages of the present general inventive concept 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 general inventive concept.

The present general inventive concept also provides an image forming apparatus capable of reducing manufacturing costs by employing a simple structure to guide paper, which is manually fed, without additional guide members.

The present general inventive concept also provides a paper cassette of an image forming apparatus including a manual paper feeder.

Additional aspects and utilities of the present general inventive concept 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 general inventive concept.

The foregoing and/or other aspects and utilities of the present general inventive concept may be achieved by providing an image forming apparatus including: a paper cassette provided with a guide groove formed at a portion of a front surface thereof and having a width corresponding to a sheet of paper; and a case having a cassette attachment part for inserting the paper cassette. The sheet of paper can be manually fed through a space defined by the guide groove and the cassette attachment part.

The cassette attachment part may be formed at a lower part of the case, and the guide groove may be formed at an upper part of the paper cassette. In this case, the manually fed paper may be readily seated on the guide groove by its own weight. In addition, the guide groove may have a multi-stage structure to guide sheets of paper having various widths.

The paper cassette may include a resilient projection formed at its outer surface, and the cassette attachment part of the case may include a threshold formed at a position, spaced apart from the resilient projection, at which the paper cassette is fully inserted into the cassette attachment part. Therefore, the resilient projection can be hooked by the threshold when the paper cassette is drawn out by a predetermined distance.

The cassette attachment part may have a paper introduction port formed at its structure corresponding to the guide groove of the paper cassette, to manually feed paper. In this case, the apparatus may further include guide members installed at the paper introduction port to facilitate lateral sliding along the paper introduction port. Further, the case may include a manual feed roller for conveying the sheet of paper manually fed through a space defined by the guide groove and the cassette attachment part.

The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing a paper cassette of an image forming apparatus including: a cassette body having an automatic paper feeder for automatically feeding paper; and a manual paper feeder integrally formed with a portion of the cassette body for manually feeding paper.

The manual paper feeder may include a guide groove formed at a portion of a front surface of the cassette body and having a width corresponding to the paper to enable manual feeding of the paper. In this case, the guide groove may have a multi-stage structure having different widths corresponding to paper of various widths.

Guide members may be installed adjacent to the guide groove to be adjusted to the width of the paper.

The cassette body may have a paper support surface formed at a portion thereof to function as a support plate for supporting a bottom surface of paper manually fed into the guide groove.

The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing an image forming apparatus, including: a case to contain a paper cassette therein, the case including a cassette attachment part formed at a front part thereof to slidably receive a paper cassette; and a paper cassette including an automatic paper feeder portion to contain paper therein to be automatically fed into the image forming apparatus, and a front wall portion having a grooved portion formed at an upper surface thereof and facing the cassette attachment part to receive paper manually fed therebetween.

The foregoing and/or other aspects and utilities of the present general inventive concept may also be achieved by providing an image forming apparatus, including: a front surface portion including a cassette attachment part formed therein to receive a paper cassette, and a paper introduction portion formed along a predetermined length of a horizontally extending portion of the cassette attachment part to receive manually fed paper therein; and a paper cassette including a body portion to contain papers to be automatically fed within the image forming apparatus, and a front surface portion including a groove portion formed therein having multi-stepped grooves facing opposite the paper introduction portion to receive corresponding multiple sized manually fed paper therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the present general inventive concept 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 perspective view of a conventional image forming apparatus including a manual paper feeder;

FIG. 2 is a perspective view of an image forming apparatus in accordance with an embodiment of the present general inventive concept;

FIG. 3 is a front view of the image forming apparatus of the embodiment of FIG. 2;

FIG. 4 is a front view of an image forming apparatus in accordance with another embodiment of the present general inventive concept;

FIGS. 5A and 5B are side cross-sectional views of the image forming apparatus of the embodiment of FIG. 2, a paper cassette of which can be drawn therefrom by a predetermined distance;

FIG. 6 is a front view of an image forming apparatus in accordance with still another embodiment of the present general inventive concept, a paper cassette of which can drawn therefrom by a predetermined distance; and

FIG. 7 is a cross-sectional view taken along line I-I′ of the image forming apparatus illustrated in FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present general inventive concept by referring to the figures.

FIG. 2 is a perspective view of an image forming apparatus in accordance with an embodiment of the present general inventive concept, FIG. 3 is a front view of the image forming apparatus of the embodiment of FIG. 2.

Referring to FIGS. 2 and 3, an image forming apparatus 100 in accordance with an embodiment of the present general inventive concept includes a case 111 having a cassette attachment part 111a formed at a lower portion thereof, and a paper cassette 118 that inserts into the cassette attachment part 111a.

As illustrated in FIGS. 2, 3, 5A and 5B, the paper cassette includes a cassette body 118c having an automatic paper feeder 118e therein, and a manual paper feeder 120 integrally formed on the cassette body 118c. Therefore, a sheet of paper 116 can be automatically fed into the case 111 through the automatic paper feeder 118e, or manually fed into the case 111 through the manual paper feeder 120.

The manual paper feeder 120 may include a guide groove 118a formed at an upper part of the cassette body 118c, such as at a part of a front surface of the cassette body 118c, for example, a center part, a width of which corresponds to different sizes of papers to be fed into the image forming apparatus 100. Therefore, the sheet of paper 116 can be manually fed into the case 111 through the guide groove 118a. The guide groove 118a may alternatively be formed at a lower part or at side parts of the cassette body 118c, rather than at the upper part. However, in order to correspond with a conventionally positioned paper feed roller, the guide groove 118a is formed at the upper part or the lower part of the cassette body 118c.

The guide groove 118a may have a multi-stage shape as illustrated in FIGS. 2 and 3 in order to guide papers of various sizes such as envelopes, postcards, 3×5 inch paper, B5, A5, B4, A4, and so on. In other words, the guide groove 118a can include a plurality of groove portions as illustrated in FIGS. 2 and 3. Here, the number and width of the multi-stage of the guide groove 118a may be determined depending on the type of the sheet of paper or papers 116 to be inserted. In addition, a lever 118b is formed at a lower front part of the cassette body 118c, just below the guide groove 118a, such that a user can grasp the lever 118b to pull the paper cassette 118 out of the image forming apparatus 100 or push the paper cassette 118 into the image forming apparatus 100.

In addition, the cassette attachment part 111a of the case 111 has a shape corresponding to a cross-section of the paper cassette 118 to be inserted therein. Further, a paper introduction port 111b to manually feed a sheet of paper is formed at a surface of the cassette attachment part 111a to correspond with the guide groove 118a of the paper cassette 118. The paper introduction port 111b may have a width slightly larger than a maximum width of recording media that can be manually fed, and may be integrally formed with the cassette attachment part 111a.

The manual paper feeder 120 to feed sheets of paper 116 (or other recording media) one by one is a part at which the sheet of paper 116 is fed into the case 111. In this embodiment, a lower surface and side surfaces of the manual paper feeder 120 are defined by a bottom surface and side surfaces of the guide groove 118a of the paper cassette 118, and an upper surface of the manual paper feeder 120 is defined by the paper introduction port 111b of the case 111.

With the arrangement as described above, the paper introduction port 111b formed at an upper surface of the cassette attachment part 111a of the case 111 can guide a sheet of paper 116 having a width substantially equal to the width of the paper introduction port 111b. In an alternative embodiment, the manual paper feeder 120 may not include the paper introduction port 111b. That is, the paper 116 can be fed through a space defined by the guide groove 118a and the cassette attachment part 111a. In this case, the manual paper feeder 120 is formed by a co-operation between the paper cassette 118 and the cassette attachment part 111a such that different size spaces to feed paper are provided therebetween. One surface of the manual paper feeder 120 is defined by the cassette attachment part 111a formed at the case 111, and another three surfaces of the manual paper feeder 120 are defined by portions of the guide groove formed at the paper cassette 118, such as, for example, the portions illustrated as positioned in the middle of the cassette body 118c directly above the lever 118b.

However, in order to feed a sheet of paper 116 having a larger width than the portions of the guide groove 118a formed at the paper cassette 118, the guide groove 118a should also have a portion that is formed at an upper end of the cassette body 118c with a large width to correspond with the paper surface of the introduction port 111b as illustrated in FIGS. 2 and 3. When the outermost portion of the guide groove 118a has the large width to correspond with the paper surface of the introduction port 111b, a center part of the sheet of paper 116 may sag so that both sides edges of the sheet of paper 116 become separated from edges of the guide groove 118a, thereby causing the sheet of paper 116 to be incorrectly guided. Therefore, the paper introduction port 111b also includes a shape to form a groove portion having a large width formed at the cassette attachment part 111a and directly above the cassette body 118c to receive larger size sheets of paper 116.

FIG. 4 is a front view of an image forming apparatus in accordance with another embodiment of the present general inventive concept.

Referring to FIG. 4, an image forming apparatus 100 may further include guide members 124, in addition to the features described above with respect to the embodiment of FIGS. 2 and 3. The guide members 124 laterally slide along the paper introduction port 111b of the manual paper feeder 120 to enable insertion of paper 116 of various sizes while guiding the inserted papers 116. Though the guide groove 118a and the paper introduction port 111b can guide standard sizes of paper 116 and smaller sizes such as envelopes, postcards, and 3×5 inch, further installation of the guide members 124 allows any size of paper 116, as well as the standard sizes, envelopes, postcards, and 3×5 inch to be smoothly guided.

FIGS. 5A and 5B are side cross-sectional views of the image forming apparatus of the embodiment illustrated in FIG. 2, the paper cassette 118 of which can be drawn therefrom. FIG. 5A illustrates the paper cassette 118 being fully inserted into the cassette attachment part 111a, and FIG. 5B illustrates the paper cassette 118 being drawn from the cassette attachment part 111a to the exterior thereof by a predetermined distance.

Referring to FIGS. 2, 5A and 5B, the cassette attachment part 111a is formed at a lower part of the case 111, and the paper cassette 118 is slidably inserted into the cassette attachment part 111a.

The case 111 includes a manual feed roller 131 rotatable by a signal from a controller (not illustrated) to convey a manually fed piece of paper 116 to an image forming unit (not illustrated) installed in the image forming apparatus 100, and an idle roller 133 to rotatably engage with the manual feed roller 131 to generate a friction force to convey the sheet of paper 116.

As illustrated in FIG. 5B, when the sheet of paper 16 is fed in a state in which the paper cassette 118 is drawn out of the image forming apparatus 100 by the predetermined distance, an upper paper support surface 118d of the cassette body 118c functions as a support member to support the manually fed paper 116. That is, the paper support surface 118d of the cassette body 118c supports a bottom surface of the manually fed paper 116. Therefore, when the sheet of paper 116 is manually fed along the guide groove 118a, the paper support surface 118d of the cassette body 118c supports a bottom surface of the manually fed sheet of paper 116 to remarkably reduce curling of the sheet of paper 116 as the manually fed paper 116 passes between the rollers 131 and 133.

While the paper cassette 118 may be freely drawn out of the image forming apparatus 100 by a distance desired by a user to support the paper 116 thereon at the paper support surface 118d, a means to accurately position the paper cassette 118 at a position at which sagging of the sheet of paper 116 can be minimized can additionally be provided as described below with respect to FIGS. 6 and 7.

FIGS. 6 and 7 illustrate an example of a positioning unit to accurately position the paper cassette 118 at a position at which sagging of the sheet of paper 116 can be minimized. P FIG. 6 is a front view of an image forming apparatus in accordance with still another embodiment of the present general inventive concept, a paper cassette of which can be drawn therefrom by a predetermined distance, and FIG. 7 is a cross-sectional view taken along line I-I′ of the image forming apparatus illustrated in FIG. 6.

Referring to FIGS. 6 and 7, the paper cassette 118 is slidably inserted into the cassette attachment part 111a of the case 111.

The paper cassette 118 can include a resilient projection 140 formed at one side thereof, and the cassette attachment part 111a of the case 111 has an elongated groove 111c extending in a longitudinal direction of the cassette attachment part 111a, thereby allowing the resilient projection 140 to be inserted and guided in the elongated groove 111c (see FIG. 6). While the elongated groove 111c is optional in this embodiment, when the elongated groove 111c is provided, a gap may be generated between the side surface of the paper cassette 118, at which the resilient projection 140 is formed, and the cassette attachment part 111a to provide a lateral movement of the paper cassette 118 with respect to the image forming apparatus 100. Therefore, in order to minimize the lateral movement of the paper cassette 118, the elongated groove 111c is formed at a portion of the cassette attachment part 111a, along which the resilient projection 140 moves, and the remaining portions of the cassette attachment part 111a can have a shape conforming to the paper cassette 118.

In addition, a threshold 111d can be formed at a predetermined position within the elongated groove 111c of the case 111, along which the resilient projection 140 moves, such that the resilient projection 140 can be stopped at a predetermined position within the elongated groove 111c.

The resilient projection 140 can include a hollow cylindrical part 143 projecting perpendicular to the side surface of the paper cassette 118, a cap 141 inserted over an end opening of the cylindrical part 143, and a spring 145 inserted into the cylindrical part 143 to create an elastic force so that the cap 141 can move in contact with an inner surface of the case 111.

The resilient projection 140 has a predetermined elastic force such that the resilient projection 140 is stopped by the threshold 111d to prevent further movement of the paper cassette 118 when less than a predetermined force is applied. However, when the predetermined force is applied to the cassette 118, the resilient projection 140 rides over the threshold 111d such that the paper cassette 118 can be fully drawn out of the image forming apparatus 100. Therefore, the spring 145 installed in the resilient projection 140 can have a low coefficient of elasticity and the threshold 111d can have a smooth curved surface such that a user can feel the stopping of the resilient projection 140 by the threshold 111d, to appropriately position the paper cassette 118 and readily draw the paper cassette 118 out of the image forming apparatus 118 to a desired position.

Hereinafter, operations of the image forming apparatus 110 in accordance with an embodiment of the present general inventive concept will be described.

First, a user grips the lever 118b of the paper cassette 118 to draw out the paper cassette 118. At this time, the resilient projection 140 formed at the side surface of the paper cassette 118 is elastically biased against the inner surface of the case 111 to move in close contact with the elongated groove 111c.

Then, when the paper cassette 118 is drawn out to a predetermined distance, the resilient projection 140 comes in contact with the threshold 111d formed at the inner surface of the case 111 to stop the cassette 118 at the drawn position of the paper cassette 118.

Next, when a predetermined piece of paper 116 to be fed is positioned over the guide groove 118a of a central upper portion of the paper cassette 18, the sheet of paper 116 drops down to be seated on the guide groove 118a by its own weight. The guide groove 118a has a multi-stage structure to feed paper 116 of various sizes such as 3×5 inch paper, envelopes, postcards, and so on. A rear end of the seated paper 116 becomes supported by an upper end surface of the drawn paper cassette 118 to prevent the sheet of paper 116 from curling while being fed into the case and then between the manual feed roller 131 and the idle roller 133.

When the sheet of paper 116 is pushed into the case 111, the paper is slid in with both sides being in close contact with sidewalls of the guide groove 118a, and a front end of the sheet of paper 116 is inserted between the manual feed roller 131 and the idle roller 133. At this time, a controller (not illustrated) rotates the manual feed roller 131 under the control of the image forming apparatus 100 to convey the piece of paper 116 to the image forming part (not illustrated). Since the conveyed paper 116 is guided by the guide groove 118a and fed to an accurate position, the sheet of paper 116 can be prevented from jamming or entering the case 111 crookedly. Here, jamming refers to when a sheet of paper gets caught along a conveyance path, and entering crookedly refers to a case when the sheet of paper is fed into the case 111 at an angle with respect to a paper feeding direction.

Meanwhile, when the sheet of paper 116 has a different width than the portions of the multi-stage guide groove 118a, the guide members 124 installed at the paper introduction port 111b of the manual paper feeder 120 can be laterally slid to be in harmony with the width of the sheet of paper 116 to be fed. As a result, it is possible to accurately feed the paper as if the paper was being guided by the guide groove 118a.

As can be seen from the foregoing, an image forming apparatus in accordance with embodiments of the present general inventive concept has a simplified structure as well as improved performance due to removal of an intermediate part between a cassette attachment part and a paper insertion slot.

In addition, an image forming apparatus in accordance with embodiments of the present general inventive concept is capable of preventing a sheet of paper from jamming or skewing by forming a paper guide groove having portions with various widths at an upper surface of a paper cassette, thereby enabling accurate feeding of the paper without an additional guide member.

Further, an image forming apparatus in accordance with embodiments of the present general inventive concept is capable of supporting a paper including a rear end thereof on an upper end of the paper cassette drawn out of the image forming apparatus to a predetermined distance to prevent the paper from curling while being fed therein, by forming a resilient projection at a side of the paper cassette and a threshold at an inner wall of the case.

Although a few embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.