JP2011175059A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of suitably discharging air inside the body of the image forming apparatus to the outside. <P>SOLUTION: A vent 151 is provided on a side surface of a housing 101. An opening 111 is provided on a manual feeding tray 110. The manual feeding tray 110 can take a placing state where it is opened and a housing state where it is closed. In the housing state, the manual feeding tray 110 is arranged to face the side surface of the housing 101 on a side in which the vent 151 exists. Then, the air discharged to the outside from the inside of the housing 101 through the vent 151 by an exhaust fan 150 is discharged from the opening 111. Furthermore, in the placing state, the air inside the housing 101 is exhausted satisfactorily to the outside of the housing 101 from the vent 151 by the exhaust fan 150. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus. More specifically, the present invention relates to an image forming apparatus capable of suitably discharging the air inside the image forming apparatus main body to the outside.

  The image forming apparatus exposes the surface of the charged image carrier to form an electrostatic latent image, applies toner to the image and develops it, and transfers the obtained toner image onto a recording medium to form an image. To form. In general, a fixing device is provided to fix the toner image on the recording medium. The fixing device is also a heating device for heating the recording medium. Therefore, the fixing device generates heat. If the heat generated by such a fixing device is trapped inside the image forming apparatus main body, for example, the toner inside the developing container may be hardened. When the toner is hardened, the quality of the image formed with the toner is low.

Therefore, in order to release the heat inside the image forming apparatus main body to the outside, Patent Document 1 (see FIG. 2) and Patent Document 2 (see FIG. 1 and the like) are provided with a fan for discharging air to the outside. An image forming apparatus is disclosed. Patent Document 3 (see FIGS. 1 to 3) discloses an image forming apparatus in which a ventilation member serving as an air flow path is provided near a developing container and a fixing device. Further, Patent Document 4 (see FIGS. 4A and 4B) discloses an image forming apparatus that causes air to flow inside the image forming apparatus body in conjunction with the loading / unloading operation of the paper feed cassette (Patent Document). 4th paragraph
[0054] to paragraph [0056]).

JP-A-5-27533 JP-A-6-161199 JP 2009-14825 A JP 2009-230053 A

  In recent years, downsizing of image forming apparatuses has been highlighted as a technical problem. This is to make effective use of the space in the office. In order to achieve such compactness, the exhaust port and the manual feed tray are often provided close to each other. Therefore, when the manual feed tray is stored, the exhaust device and the manual feed tray are close to each other and face each other.

  However, when the exhaust device and the manual feed tray are close to each other as described above, the air discharged from the image forming apparatus main body by the exhaust device is blocked by the stored manual feed tray. As a result, the flow of air is changed and the air may reenter the image forming apparatus main body. Thus, the cooling effect inside the image forming apparatus cannot be obtained sufficiently.

  Nonetheless, the direction of air exhaust is determined by safety standards so that it is exhausted diagonally downward from the side of the body, and the direction cannot be changed greatly. On the other hand, if the manual feed tray is too small, paper cannot be placed. In addition, increasing the size of the exhaust system or adding an exhaust system is not suitable for the purpose of downsizing.

  The present invention has been made to solve the above-described problems of the prior art. That is, an object of the present invention is to provide an image forming apparatus capable of suitably discharging the air inside the image forming apparatus main body to the outside.

  In order to solve this problem, an image forming apparatus according to the present invention includes an image forming unit that forms an image on a sheet, a fixing device that heats and fixes an image on the sheet formed by the image forming unit, and an image A housing having a forming unit and a fixing device inside, a vent opening in a part of the side of the housing, and an air that is disposed inside the housing and is vented to the outside through the vent And an exhaust device that discharges the paper to the image forming unit from the outside of the housing. The manual paper placement unit includes a placement state in which manual paper can be placed, and a storage state in which the placement surface is disposed so as to face the side surface of the housing where the vent is provided. In addition to being able to take at least two states, a through-hole penetrating in the thickness direction is provided. In the image forming apparatus, in the stored state, the air exhausted to the outside of the housing by the vents can be further discharged to the outside from the through hole of the manual paper placement unit. That is, the air inside the housing can be discharged to the outside without stagnation not only in the mounted state but also in the stored state.

  In the image forming apparatus described above, the first rib formed in parallel with the first direction and the second direction intersecting with the first direction are formed on one surface of the manual paper placement unit. It is preferable that a plurality of the second ribs are provided, and the through holes are formed at the positions of the cells defined by the first ribs and the second ribs. This is because the first rib and the second rib serve as rectifying fins that regulate the flow of air. This is because air flows smoothly.

  In the image forming apparatus described above, in the loaded state, it is more preferable that the first direction is a sheet conveyance direction. This is because the manual feed paper is suitably transported.

  In the image forming apparatus described above, a plurality of air vents are formed on the side surface of the housing, and are located between the air vents on the side surface of the housing, and are inclined higher toward the inside of the housing and lower toward the outside. It is further preferable that the second ribs are arranged so as to be inclined closer to the inner side of the casing and lower toward the outer side in the retracted state. This is because the air can be exhausted more suitably obliquely below the image forming apparatus main body.

  In the image forming apparatus described above, in the retracted state, the lowermost of the rectifying plates is extended in the direction of the inclined surface from the line extending the uppermost of the rectifying plates in the direction of the inclined surface. It is further preferable that at least one through-hole is present in the manual paper loading portion within the range up to the line. It is because it can exhaust more suitably.

  According to the present invention, there is provided an image forming apparatus capable of suitably discharging the air inside the image forming apparatus main body to the outside.

1 is a perspective view for explaining an image forming apparatus according to the present invention. FIG. 4 is a perspective view showing a state in which a manual feed tray in the image forming apparatus according to the present invention is widened. 1 is a schematic configuration diagram for explaining an image forming apparatus according to the present invention. FIG. 3 is a perspective view (No. 1) for explaining a manual feed tray of the image forming apparatus according to the present invention. FIG. 5 is a perspective view (No. 2) for explaining a manual feed tray of the image forming apparatus according to the present invention. It is sectional drawing which shows a part of FF cross section of FIG.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the accompanying drawings. In the present embodiment, the present invention is embodied in an image forming apparatus.

1. Image Forming Apparatus FIG. 1 is a perspective view of an image forming apparatus 100 according to this embodiment. The image forming apparatus 100 includes an image forming unit inside the casing 101 and a manual feed tray 110 at a lower portion of the side surface outside the casing 101. The manual feed tray 110 is rotatably supported at the lower end. The manual feed tray 110 can be opened and closed by the user operating the knob portion 114. FIG. 1 shows a state where the manual feed tray 110 is closed. FIG. 2 shows a state where the manual feed tray 110 is opened. As shown in FIG. 2, when the manual feed tray 110 is opened, the air vent 151 is visible from the outside. In FIG. 1, the vent 151 is not visible because it is hidden behind the manual feed tray 110. The structure of the manual feed tray 110 and the vent 151 will be described in detail later.

  FIG. 3 is a schematic configuration diagram of an internal mechanism of the image forming apparatus 100 of the present embodiment. As shown in FIG. 3, the image forming apparatus 100 according to this embodiment includes an image forming unit 1 and a fixing device 70. Referring to FIG. 1, the image forming unit 1 is inside the area indicated by the arrow K inside the housing 101. Referring to FIG. 1, the fixing device 70 is inside the area indicated by the arrow L inside the housing 101. The image forming unit 1 includes a photosensitive drum 10, a charging roller 20, an exposure device 30, a developing device 40, a transfer roller 50, and a cleaning device 60.

  The photosensitive drum 10 is an image carrier for carrying an electrostatic latent image or a toner image on the surface thereof. The charging roller 20 is for uniformly charging the surface of the photosensitive drum 10. The exposure device 30 is for drawing an electrostatic latent image on the surface of the photosensitive drum 10 by exposing the surface of the photosensitive drum 10 uniformly charged by the charging roller 20.

  The developing device 40 is for developing the electrostatic latent image carried on the photosensitive drum 10. The developing device 40 has a developing roller 41. The developing roller 41 is a developing member for applying a developer to the photosensitive drum 10. The transfer roller 50 is for transferring the toner image carried on the photosensitive drum 10 onto a sheet.

  The cleaning device 60 is for collecting development residual toner from the surface of the photosensitive drum 10. The cleaning device 60 includes a cleaning blade 61 and a waste toner box 62. The cleaning blade 61 is a cleaning member for scraping off development residual toner from the surface of the photosensitive drum 10. The waste toner box 62 is a container for collecting the toner scraped off by the cleaning blade 61.

  The fixing device 70 has a roller pair including a fixing roller 71 and a pressure roller 72. The fixing roller 71 is a roller for heating the toner transferred to the paper. For this reason, the fixing roller 71 has a heat source for generating heat therein. The roller pair of the fixing roller 71 and the pressure roller 72 is for heating and pressurizing the toner by the fixing roller 71. Thus, the fixing roller 71 generates heat inside thereof. Therefore, the temperature inside the image forming apparatus 100 increases with the heat generated by the fixing roller 71.

  The photosensitive drum 10 rotates in the direction of arrow A in FIG. The charging roller 20 rotates in the direction of the arrow B in FIG. 3, that is, the direction following the rotation direction of the photosensitive drum 10. The developing roller 41 rotates in the direction indicated by the arrow C in FIG. 3, that is, the direction following the rotation direction of the photosensitive drum 10. However, the developing roller 41 may be rotated in the direction opposite to the arrow C, that is, around the photosensitive drum 10 and the counter. This is because it can be developed. The transfer roller 50 rotates in the direction of arrow D in FIG. 3, that is, in the direction following the photosensitive drum 10. The paper travels in the direction of arrow P.

  Next, the basic operation of the image forming apparatus 100 will be briefly described. The photosensitive drum 10 rotates in the direction of arrow A in FIG. 3 as described above. And the process shown below is performed with the rotation. First, the charging roller 20 uniformly charges the surface of the photosensitive drum 10 while rotating in the direction of arrow B. The charged surface potential of the photosensitive drum 10 is the background potential of the image.

  Downstream of that, the exposure device 30 draws an electrostatic latent image on the surface of the photosensitive drum 10. That is, the potential at the exposed portion becomes the image portion potential. Further downstream, the developing roller 41 rotating in the direction of arrow C in FIG. 3 applies toner to the electrostatic latent image formed on the surface of the photosensitive drum 10. As a result, a toner image is formed on the surface of the photosensitive drum 10. This toner image is transferred onto the sheet conveyed in the direction of arrow P by the transfer roller 50 of FIG.

  Thereafter, the sheet on which the toner image has been transferred is heated and pressurized by a pair of fixing rollers 71 and a pressure roller 72. As a result, the toner image is fixed on the paper. A part of the heat generated by the fixing roller 71 is transmitted to the sheet, and the remaining heat is radiated to the inside of the image forming apparatus 100.

2. As shown in FIG. 2, the manual feed tray 110 according to the present embodiment is supported at the lower end of the manual feed tray 110 and can be opened and closed by rotating around the lower end. Therefore, the manual feed tray 110 can take two states, a closed storage state (see FIG. 1) and an open placement state (FIG. 2).

  The manual tray 110 is opened and closed by the user operating the knob unit 114. When the paper is not supplied by the manual feed tray 110, the manual feed tray 110 can be stored on the side surface of the main body of the image forming apparatus 100 as shown in FIG. When the manual feed tray 110 is in an open state as shown in FIG. 2, it is possible to make a copy using the user's manual feed paper. In other words, the manual feed tray 110 is a manual paper placement unit for placing manual paper. The transport direction in this case is the direction of arrow E in FIG.

  FIG. 4 is a perspective view of the manual feed tray 110 of the image forming apparatus 100 as seen from the back side. An arrow E in FIG. 4 indicates the same sheet conveyance direction as the arrow E in FIG. As shown in FIG. 1, the back surface 116 of the manual feed tray 110 is a surface that is stored on the side surface of the main body of the image forming apparatus 100 and cannot be seen from the outside when not in use. This is the surface on which the manual paper is placed when in use.

  As shown in FIG. 4, a plurality of vertical ribs 113, horizontal ribs 112, and vertical ribs 115 are formed on the back surface 116 of the manual feed tray 110. The longitudinal rib 113 is a first rib formed in parallel with the paper transport direction. The lateral rib 112 is a second rib formed in a direction perpendicular to the paper transport direction. The longitudinal ribs 115 are ribs formed in parallel with the paper transport direction. Note that the paper transport direction is the first direction. The direction perpendicular to the paper transport direction is the second direction.

  The lateral rib 112 is formed over a range from one end of the plurality of longitudinal ribs 113 to the other end. The vertical ribs 113 are formed over a range from the upper end 118 of the manual feed tray 110 to the one located among the plurality of horizontal ribs 112 on the most downstream side in the paper transport direction (arrow E).

  Both the horizontal rib 112 and the vertical ribs 113 and 115 are for supporting the sheet from below. Further, it also serves as a strength reinforcing portion for preventing the manual feed tray 110 itself from being bent by the weight of the paper when the paper is placed on the manual feed tray 110. As will be described in detail later, the manual feed tray 110 also serves as a rectifying fin.

  As shown in FIG. 4, the longitudinal ribs 113 and the lateral ribs 112 are formed so as to intersect in a lattice pattern. And the grid | lattice grid location is the opening part 111 which is opened. The opening 111 is a through-hole penetrating the manual feed tray 110 in the thickness direction. Since the vertical ribs 113 and the horizontal ribs 112 are arranged so as to intersect with each other in a lattice pattern, the strength of the manual feed tray 110 is sufficient even if the opening 111 is formed.

  FIG. 5 is a perspective view of the manual feed tray 110 viewed from the front side. The front surface 117 is a surface on the side that can be visually recognized from the outside when the manual feed tray 110 is stored. As shown in FIG. 5, the opening 111 can be seen from the outside when viewed from the surface 117. As will be described later, when the manual feed tray 110 is stored in the main body of the image forming apparatus 100, the opening 111 serves as a vent hole for the air exhausted from the main body of the image forming apparatus 100.

  FIG. 6 is a cross-sectional view showing a part of the FF cross section of FIG. FIG. 6 shows a state where the manual feed tray 110 is stored. In this stored state, the manual feed tray 110 faces the side surface of the housing 101. An exhaust fan 150 is provided inside the housing 101 of the image forming apparatus 100. The exhaust fan 150 is an exhaust device for discharging the air inside the housing 101 to the outside of the housing 101. The exhaust fan 150 is disposed immediately inside the outer surface plate of the housing 101 and at a position close to the fixing device 70.

  As shown in FIG. 6, a plurality of vents 151 shown in FIG. 2 are provided on the side surface of the casing 101 at a position downstream of the exhaust fan 150 in the blowing direction. The vent 151 is a through hole that penetrates a part of the side surface of the housing 101. That is, the air flowing from the exhaust fan 150 is discharged from the inside of the housing 101 to the outside. The vent 151 has an elongated slit shape as shown in FIG.

  As shown in FIG. 6, a plurality of rectifying plates 152 are arranged between the vents 151 of the housing 101. That is, the vent 151 is between the current plates 152. The rectifying plate 152 is for determining the direction in which the air exhausted from the vent 151 flows. The rectifying plate 152 is disposed so as to be inclined with respect to the side surface of the housing 101. The inclination is higher toward the inner side of the casing 101 and lower toward the outer side. This is because the air inside the casing 101 pushed out from the exhaust fan 150 is discharged in the direction of the arrow G, that is, in a direction obliquely below the casing 101.

  In the stored state as shown in FIG. 6, the lateral rib 112 of the manual feed tray 110 is substantially parallel to the rectifying plate 152. That is, the inclination of the lateral rib 112 is about the same as the inclination of the rectifying plate 152. The inclination is higher toward the inner side of the housing 101 and lower toward the outer side. This is because the air discharged from the inside of the housing 101 in the direction of the arrow G is smoothly discharged to the outside. Although it is preferable that the lateral rib 112 and the rectifying plate 152 are almost parallel as described above, they do not necessarily have to be exactly parallel.

  Next, the positional relationship between the current plate 152 and the lateral rib 112 in the retracted state will be described. The uppermost one of the rectifying plates 152 extends from the line extending in the direction of the inclined surface, that is, the direction of the arrow G, and the lowermost one of the rectifying plates 152 extends in the direction of the inclined surface, that is, the direction of the arrow G. It is preferable that at least one opening 111 exists in the manual feed tray 110 within the range up to the extended line. This is because the flow of exhausted air is smooth.

  Here, the flow of air discharged from the exhaust fan 150 will be described. The direction in which the air exhausted from the vent 151 flows is the direction along the inclination of the rectifying plate 152, that is, the direction of the arrow G in FIG. In this direction, the air inside the housing 101 is discharged to the outside of the housing 101. The air exhausted in the direction of the arrow G is exhausted to the outside of the image forming apparatus 100 as indicated by the arrow H. That is, it temporarily flows in the space between the side surface of the housing 101 and the manual feed tray 110. Then, it flows from the opening 111 of the manual feed tray 110 to the outside of the image forming apparatus 100. At this time, the vertical rib 113 and the horizontal rib 112 also serve as rectifying fins.

  In the case where the manual feed tray 110 is open as shown in FIG. 2, there is no member that obstructs ventilation at a location outside the ventilation hole 151 on the side surface of the housing 101. Therefore, the air inside the housing 101 can be suitably exhausted. Therefore, there is no possibility that the temperature inside the main body of the image forming apparatus 100 will rise too much.

3. Comparison with Conventional Image Forming Apparatus Here, a conventional image forming apparatus having no opening 111 will be described for comparison. In an image forming apparatus including a manual feed tray in which no opening 111 is provided, an airflow flows in the direction of arrow I or arrow J as shown in FIG. That is, the heated air exhausted in the direction of the arrow G is returned to the inside of the main body of the image forming apparatus again on the inner surface of the manual feed tray (corresponding to 110).

  Therefore, heat tends to be trapped inside the image forming apparatus main body. An image forming unit exists ahead of the arrows I and J in FIG. Toner is accommodated in the developing device of the image forming unit. If the heat is accumulated in the vicinity of the developing device, the toner may be hardened. Needless to say, when an image is formed using solidified toner, the quality of the image is low.

  As described above, in the conventional image forming apparatus, if the image is formed with the manual feed tray stored, the temperature inside the image forming apparatus main body may be excessively increased. As a result, there is a possibility that the quality of an image formed is low. However, in the image forming apparatus 100 of this embodiment, even if image formation is performed with the manual feed tray 110 stored, there is no possibility that the temperature inside the main body of the image forming apparatus 100 will rise excessively.

  As indicated by an arrow M in FIG. 6, the effect of the present invention is greater as the distance M between the upper end 118 of the manual feed tray 110 and the housing 101 is smaller. For example, when the interval M is within 6 mm, the effect is higher. This is because the air discharged in the direction of the arrow G is less likely to be discharged outside through the gap between the upper end 118 of the manual feed tray 110 and the housing 101 as the interval M is narrower.

4). Summary As described above in detail, the image forming apparatus 100 according to the present embodiment is provided with the opening 111 in the manual feed tray 110. Therefore, there is no possibility that the air exhausted by the exhaust fan of the image forming apparatus rebounds on the inner surface of the manual feed tray and enters the inside of the image forming apparatus again. As a result, an image forming apparatus is realized in which heat is not trapped inside.

  Note that this embodiment is merely an example, and does not limit the present invention. Therefore, the present invention can naturally be improved and modified in various ways without departing from the gist thereof. For example, it can be used not only for a copying machine but also for a printer. Further, the present invention can be applied to an image forming apparatus having a function of receiving a print job from a public line and forming an image, and other apparatuses for forming an image. Also, it can be applied regardless of the type of toner. Ink may be used instead of toner.

  Further, the longitudinal ribs 113 are provided in parallel with the sheet conveying direction, and the lateral ribs 112 are provided perpendicular to the sheet conveying direction. However, these orientations are not necessarily the orientations of the present embodiment. However, it is preferable that the longitudinal ribs 113 are parallel to the paper transport direction for transporting the paper. Further, although the vertical rib 113 and the horizontal rib 112 are provided on the back surface 116 of the manual feed tray 110, they may be provided on the front surface 117.

DESCRIPTION OF SYMBOLS 1 ... Image forming part 10 ... Photoconductor drum 20 ... Charge roller 30 ... Exposure apparatus 40 ... Developing apparatus 50 ... Transfer roller 70 ... Fixing apparatus 71 ... Fixing roller 72 ... Pressure roller 100 ... Image forming apparatus 110 ... Manual feed tray 111 ... Opening portion 112 ... transverse rib 113 ... longitudinal rib 116 ... back surface 117 ... front surface 150 ... exhaust fan 151 ... vent hole 152 ... current plate

Claims (5)

An image forming unit for forming an image on paper;
A fixing device that heats and fixes an image on a sheet on which an image is formed by the image forming unit;
A housing provided with the image forming unit and the fixing device;
A vent opening in a part of the side of the housing;
An exhaust device that is disposed inside the housing and exhausts air inside the housing to the outside through the vent;
An image forming apparatus having a manual paper placement unit for placing paper to be fed to the image formation unit from the outside of the housing;
The manual paper loading unit is
A loading state in which manual paper can be loaded;
The mounting surface can take at least two states, that is, a storage state in which the mounting surface is disposed so as to face a side surface on the side where the vent hole is provided in the housing,
An image forming apparatus comprising a through hole penetrating in a thickness direction. The image forming apparatus according to claim 1,
On one side of the manual paper loading portion,
A plurality of first ribs formed parallel to the first direction and a plurality of second ribs formed parallel to the second direction intersecting the first direction;
The through hole is
An image forming apparatus, wherein the image forming apparatus is formed at a position of a square defined by the first rib and the second rib. The image forming apparatus according to claim 2,
In the previous state,
An image forming apparatus, wherein the first direction is a paper transport direction. The image forming apparatus according to claim 2 or 3,
A plurality of the vents are formed on a side surface of the housing;
On the side of the housing,
A plurality of rectifying plates located between the vents and arranged so as to be inclined higher toward the inner side and lower toward the outer side;
The second rib is
In the storage state, the image forming apparatus is arranged so as to have a higher inclination toward an inner side of the housing and a lower inclination toward an outer side. The image forming apparatus according to claim 4,
In the storage state,
The manual sheet placement within a range from a line extending the uppermost one of the current plates in the direction of the inclined surface to a line extending the lowermost one of the current plates in the direction of the inclined surface. An image forming apparatus characterized in that at least one of the through holes exists in a portion.

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