JP6415083B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus that forms an image on a recording material by an electrophotographic image forming process.

2. Description of the Related Art In general, an image forming apparatus that forms an image on a sheet (recording material) using toner by an electrophotographic image forming process applies heat and pressure to the sheet on which the toner is transferred to fix the toner to the sheet. . In such an image forming apparatus, when the sheet is heated by the fixing device, moisture contained in the sheet evaporates into the air. At this time, if the amount of water in the air exceeds the amount of saturated water vapor, the amount of water exceeding the amount of saturated water vapor is not contained in the air and appears as water droplets attached to the paper conveyance path. In general, this phenomenon is called condensation. In particular, when the temperature of the air is low, the saturated water vapor amount is low, and the amount of condensation tends to increase. Further, in a paper that is left in a high humidity environment and contains a large amount of water, the amount of water evaporated from the paper when heated by the fixing device increases, so the amount of water droplets due to condensation also increases.
Here, as an example of a conventional image forming apparatus, an image reading apparatus is additionally arranged above the main body of the image forming apparatus for the purpose of adding other functions such as a copying function in addition to functions such as a base printer and FAX. There is something to do. When such an image reading apparatus is added, the image reading apparatus is arranged on the upper part of the main body of the image forming apparatus, a space is provided between the image reading apparatus and the main body of the image forming apparatus, and the paper discharged in this space is provided. An in-body discharge type image forming apparatus that discharges and stacks sheets on a tray has been proposed. Further, in recent years, there is an increasing demand for a desktop type image forming apparatus that is used while being placed on a desk even in such an in-body paper discharge type image forming apparatus. In order to reduce the size of such a desktop type image forming apparatus, in addition to suppressing the height of the main body of the image forming apparatus and the thickness of the image reading apparatus itself, the height of the in-cylinder discharge space is suppressed to save the image. It is necessary to make space.
When the paper transport path space such as the in-cylinder paper discharge space is reduced due to the downsizing of the device, the heat from the fixing device and the water evaporated from the paper heated by the fixing device are not diffused into the air. It may remain in a small space and appear as water droplets. In particular, water droplets due to condensation tend to adhere to the sheet conveyance path immediately after the sheet is discharged from the fixing device, such as the lower surface of the image reading apparatus. Further, in an image forming apparatus having a plurality of discharge trays in order to sort the sheets discharged from the fixing device according to the purpose of use, the plurality of discharge trays are arranged in an overlapping manner. Therefore, the space of the paper conveyance path is reduced, and water droplets due to condensation are likely to adhere to the paper conveyance path as in the case of the in-body discharge type. The water droplets adhering to these paper transport paths may adhere to the paper transported along the path, or may accumulate on the paper transport path and fall on the paper due to the action of gravity. Such adhesion of water droplets causes various problems such as contamination of the toner image, paper jams and paper wrinkles due to paper deformation caused by water droplets, poor storage on the paper discharge tray, and damage to the paper itself. May bring about.
Therefore, Patent Document 1 proposes a configuration in which an air passage is formed and water droplets adhering to the paper conveyance path are naturally dried, and the water droplets are guided to a storage unit along ribs arranged obliquely in the paper conveyance path. . Further, Patent Document 2 proposes a configuration in which water droplets flowing along ribs arranged in a paper conveyance path are absorbed by a water absorbent sheet.

JP-A-9-90855 JP 2007-119163 A

  In the configuration proposed in Patent Documents 1 and 2, there is a concern that an air passage for naturally drying water droplets, a space for arranging a storage unit, a water absorbing sheet for absorbing water droplets, and the like are required, and the apparatus becomes large. is there. In addition, it is assumed that a large amount of accumulated water droplets adhere to the paper while the water droplets flow along the ribs arranged in the paper conveyance path.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus having a simple and excellent water droplet retention property.

In order to achieve the above object, an image forming apparatus of the present invention includes:
An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A recording material guide rib capable of guiding the recording material;
A water drop rib connected to the recording material guide rib and formed lower than the recording material guide rib;
Have
The water drop rib is
The height decreases with increasing distance from the connecting portion with the recording material guide rib, and
Of the plurality of concave portions formed by the recording material guide rib and the water droplet rib, the height of the water droplet held in the concave portion formed between the recording material guide rib and the water droplet rib is the height of the recording material guide rib. Before reaching this depth, the water droplets can be moved to another recess adjacent to the recess .
In order to achieve the above object, the image forming apparatus of the present invention includes:
An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A plurality of first ribs extending in parallel with each other in the recording material conveyance direction;
A plurality of second ribs extending in a direction lower than the first rib and different from the transport direction;
A plurality of third ribs that are lower than the first ribs and extend parallel to each other in the transport direction;
With
The second rib is connected to the first rib, and the height decreases as the distance from the connecting portion increases.
In order to achieve the above object, the image forming apparatus of the present invention includes:
An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A plurality of first ribs extending in parallel with each other in the recording material conveyance direction;
A plurality of second ribs that are lower than the first ribs and extend in a direction different from the transport direction
When,
With
The second rib is connected to the first rib, and the height decreases as the distance from the connecting portion increases.
In order to achieve the above object, the image forming apparatus of the present invention includes:
An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A recording material guide portion that is provided on a surface facing the conveyance path and guides the recording material;
A plurality of recesses for holding water droplets provided on a surface facing the transport path, wherein a plurality of recesses having a height of a limitable amount of water drops that is lower than the height of the recording material guide part;
I have a,
The recess, the amount of the limit which can hold water drops farther from the recording material guide portion and said Rukoto a small.

  According to the present invention, it is possible to provide an image forming apparatus having a simple and excellent water droplet retention property.

1 is a schematic cross-sectional view showing a configuration of an image forming apparatus according to Embodiment 1 of the present invention. Schematic perspective view showing a conventional conveyance guide and conveyance surface Schematic diagram showing the configuration of the transport guide in Example 1 of the present invention The schematic diagram which shows the structure of the modification of the conveyance guide in Example 1 of this invention. Schematic sectional view showing the configuration of an image forming apparatus according to Embodiment 2 of the present invention. Schematic diagram showing the configuration of the transport guide in Example 2 of the present invention The schematic diagram which shows the structure of the modification of the conveyance guide in Example 2 of this invention. Schematic sectional view showing the configuration of an image forming apparatus according to Embodiment 3 of the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in this embodiment should be appropriately changed according to the configuration of the apparatus to which the invention is applied and various conditions. That is, it is not intended to limit the scope of the present invention to the following embodiments.

Example 1
The image forming apparatus according to the first embodiment of the present invention will be described with reference to FIGS. The image forming apparatus according to this embodiment is an electrophotographic image forming apparatus that forms an image on a recording material (recording medium) using toner by an electrophotographic image forming process. Examples of the electrophotographic image forming apparatus (hereinafter, image forming apparatus) include an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED printer, etc.), and the like. The recording material is a medium to which a toner image is transferred using an electrophotographic image forming process, and is, for example, a recording paper, an OHP sheet, a label, or the like.

[Configuration of Image Forming Apparatus]
1A and 1B are schematic diagrams illustrating a schematic configuration of an image forming apparatus according to a first exemplary embodiment of the present invention. FIG. 1A is a schematic cross-sectional view of the entire apparatus, and FIG. 1B is an enlarged configuration around a fixing device. It is a typical sectional view shown. Reference numeral 100 in FIG. 1A indicates the main body of the image forming apparatus.

  A laser scanner 25 is disposed above the apparatus main body 100, and an image forming unit 100 </ b> A is disposed below the laser scanner 25. The image forming unit 100A forms an image by an electrophotographic method, and includes four process cartridges 3 (3Y, 3M, and 3) that form toner images of yellow Y, magenta M, cyan C, and black K, respectively. 3C, 3K). Each process cartridge 3 includes a photosensitive drum 1 (1Y, 1M, 1C, 1K), a developing roller 2 (2Y, 2M, 2C, 2K), and the like, which are integrally attached to and detached from the apparatus main body 100. It is configured to be possible.

  An intermediate transfer belt unit 30 is disposed below the process cartridge 3. The intermediate transfer belt unit 30 is made of a dielectric, and includes an intermediate transfer belt 31 that is a flexible endless belt (intermediate transfer body), a driving roller 32 that circulates and moves the intermediate transfer belt 31, and a tension roller 33. Have. The intermediate transfer belt 31 is in contact with each photosensitive drum 1, and four primary transfer rollers 34 are opposed to the photosensitive drum 1 through the intermediate transfer belt 31 inside the intermediate transfer belt 31. Arranged. The primary transfer roller 34 superimposes and transfers the toner images formed on the respective photosensitive drums 1 onto the intermediate transfer belt 31, thereby forming a full-color toner image on the intermediate transfer belt 31.

  A sheet feeding unit 20 that feeds the sheet 10 as a recording material stored in the sheet feeding tray 11 is disposed at the lower part of the apparatus main body 100. In the paper feeding unit 20, the paper 10 accommodated in the paper feeding tray 11 is fed, and a secondary portion that is a nip portion between the secondary transfer roller 21 and the intermediate transfer belt 31 so as to synchronize with the formation of the toner image. It is fed to the transfer section. The sheet 10 on which the toner image has been transferred by the secondary transfer unit is conveyed to a fixing device (fixing unit) 40, where the toner image is fixed by being heated and pressed by the fixing device 40. The fixing device 40 includes a heating unit that heats the sheet to be conveyed, and a conveyance guide 41 as a guide member that guides the sheet 10 fed from the heating unit from above. The sheet 10 on which the toner image is fixed by the fixing device 40 is discharged to a discharge tray 50 provided on the upper surface of the apparatus main body 100 by a discharge roller pair 42.

[Condensation and conventional transport guide]
With reference to FIG. 1B and FIG. 2, the state of occurrence of condensation in the fixing device 40 will be described. FIG. 2 is a schematic perspective view showing the configuration of the conveyance surface of the conveyance guide when viewed in the direction F of FIG. 1B, and shows the configuration of the conveyance surface of the conveyance guide 141 in the conventional image forming apparatus. Yes.

Moisture contained in the paper 10 and toner during the image fixing is heated at the fixing nip portion 40N in FIG. 2 to become water vapor. Here, the high-temperature water vapor mainly tries to diffuse upward and laterally in the fixing device 40. Most of the high-temperature water vapor diffused upward in the fixing device 40 rises due to natural convection generated in the apparatus main body 100. The raised water vapor partially condenses on the conveyance guide 41 when the conveyance guide 41 immediately above the fixing device 40 is in a cooled state.

  In FIG. 2, the conventional transport guide 141 is provided with a plurality of paper passing ribs 141A for guiding the paper 10 in parallel with the transport direction of the paper 10 on the transport surface, and a surface 141B between the paper passing ribs 141A. Is most likely to collect water droplets due to condensation. When water droplets due to condensation on the surface 141B grow to a certain amount, they may fall due to the action of gravity and adhere to the paper being conveyed.

[Conveying guide of this embodiment]
3A and 3B are schematic diagrams illustrating a conveyance surface of the conveyance guide 41 in the image forming apparatus according to the first exemplary embodiment of the present invention. FIG. 3A is a schematic perspective view of the conveyance guide 41, and FIG. The figure which looked at the surface from the front, (c) is a sectional view of conveyance guide 41 seen in the conveyance direction of a sheet. In this embodiment, the conveyance guide 41 corresponds to the conveyance path forming unit in the present invention. In addition, the paper transport path in the present invention includes a paper stacking unit such as a paper discharge tray which is an end point of the transport path.

  Here, the transport surface of the transport guide may have different specific functions depending on how it is used in the apparatus configuration. In other words, it may be used to function as a surface that guides conveyance by placing a sheet, or to function as a surface that delimits the sheet conveyance path space and restricts the sheet from coming off the conveyance path. Sometimes used. In the case of the present embodiment, the latter is used.

  In the present embodiment, the conveyance guide 41 includes a rib portion formed of three types of ribs on the conveyance surface, specifically, a sheet passing rib 41A (first rib) and a lateral rib 41B (second rib) that cross each other in a lattice shape. Rib) and vertical rib 41C (third rib). The sheet passing rib 41A is a rib extending in the transport direction (hereinafter referred to as transport direction) of the paper 10 on the transport surface of the transport guide 41, and is mainly a rib configured to be able to guide the paper 10 in the transport direction (recording material). Guide rib or recording material guide). The horizontal rib 41B and the vertical rib 41C are ribs provided so as to intersect each other between the pair of paper passing ribs 41A (water droplet guide ribs).

  The vertical ribs 41C extend between the plurality of paper passing ribs 41A along the conveying direction in parallel with the paper passing ribs 41A (parallel ribs). In the present embodiment, two vertical ribs 41C are arranged between the pair of paper passing ribs 41A. The horizontal rib 41B extends in a direction orthogonal to the transport direction, and intersects the plurality of paper passing ribs 41A and the plurality of vertical ribs 41C (orthogonal ribs). A plurality of the lateral ribs 41B are arranged at equal intervals in the transport direction.

[Water drop retention shape]
Due to the sheet passing ribs 41A, the horizontal ribs 41B, and the vertical ribs 41C arranged as described above, a plurality of water droplet holding recesses that open in a direction perpendicular to the conveyance surface are formed on the conveyance surface of the conveyance guide 41. It is formed. There are two types of recesses to be formed. One is a first recess 181 formed by the horizontal rib 41B and the vertical rib 41C, and the second is a second recess 182 formed by the paper passing rib 41A, the horizontal rib 41B, and the vertical rib 41C. is there. The first recess 181 surrounded by the horizontal rib 41B and the vertical rib 41C is formed at a position away from the paper passing rib 41A. The second recess 182 surrounded by the sheet passing rib 41A, the pair of lateral ribs 41B connected to the sheet passing rib 41B, and the vertical rib 41C connecting the pair of lateral ribs 41B at a position facing the sheet passing rib 41A is formed between the sheet passing rib 41A and the first rib. It is formed between the recess 181. Both the first recess 181 and the second recess 182 are formed so as to be able to hold a predetermined amount of water droplets by the action of surface tension, and constitute the water droplet holding shape 80 in this embodiment.

The horizontal rib 41B and the vertical rib 41C are provided lower in height than the paper passing rib 41A. Further, the lateral rib 41B is formed so that the height decreases as the distance from the connecting portion (intersection portion) with the sheet passing rib 41A increases. Therefore, the height of the opening edge of the second recess 182 (the height of the upper surface of the rib forming the recess) decreases as the distance from the sheet passing rib 41A increases. And the 1st recessed part 181 is adjacent to the 2nd recessed part 182 in the side with the low height of the opening edge. With such a configuration, a water droplet that tends to overflow from the second recess 182 tends to overflow from the first recess 181 side away from the paper passing rib 41A. In addition, the first recess 181 is formed at a portion having the lowest height in the lateral rib 41 </ b> B, and a water droplet that exceeds the water droplet retention allowable amount (the amount that can be retained) of the recess is first than the second recess 182. The recess 181 tends to overflow.

  Each of the first recess 181 and the second recess 182 is continuously provided in the transport direction, and as shown in FIG. 3C, the height changes when viewed in the transport direction are the same. It is comprised so that it may become. That is, a row composed of a plurality of second recesses is formed on both sides in a direction orthogonal to the transport direction of a row composed of the plurality of first recesses 181 extending in the transport direction. It extends to. Therefore, the water droplets that cannot be held by the specific recesses are more likely to flow (moving easily) downward in the gravity direction along the rows of the first recesses 181 than the rows of the second recesses. Further, the first concave portion 181 and the second concave portion 182 are configured to reach the limit water droplet holding amount in each concave portion before the height of the retained water droplet reaches the height of the sheet passing rib 41A.

  By forming the water droplet holding shape 80 as described above between the paper passing ribs 41A, even when water droplets are generated due to condensation, the water droplet can be attached to the water droplet holding shape 80 by surface tension. In addition, since the first concave portion 181 and the second concave portion 182 constituting the water droplet retaining shape 80 are distributed at a plurality of locations, the amount of water retained in one concave portion is optimized, and one location is provided. A large amount of water droplets do not adhere to the surface, and the effect of accelerating the natural drying of the water droplets can be expected.

  In addition, the water droplet holding shape 80 does not interfere with the conveyance of the paper 10, which is the original function of the conveyance guide 41, so that the paper 10 holds the paper 10 more than the paper passing rib 41A as shown in the sectional view of FIG. On the other hand, it is set low. Further, the height of the water droplet holding shape 80 is reduced between the adjacent paper passing ribs 41A as the distance from the paper passing rib 41A increases. Thereby, it is possible to prevent the portion of the paper 10 away from the support (regulation) portion by the paper passing rib 41 </ b> A from coming into contact with the water droplet held by the water droplet holding shape portion 80 when the deflection or the like occurs. .

  As described above, according to the water droplet holding shape 80 of the present embodiment, even when water droplets are generated on the conveyance surface of the conveyance guide 41 due to condensation or the like, the water droplets contact the paper 10 guided by the conveyance guide 41, or the paper 10 It is possible to prevent water droplets from falling on the transport path. That is, according to the water droplet holding shape 80 of the present embodiment, water droplets due to condensation can be dispersed and held. Therefore, it is possible to prevent a large amount of water droplets from adhering to one place on the conveyance surface of the conveyance guide 41, that is, to prevent the water droplets from becoming too large at one place. Can be prevented from falling. Therefore, according to this embodiment, it is possible to prevent a problem (for example, an image defect) due to water droplets adhering to the paper 10. Moreover, since the space for special measures against condensation, a special member, etc. are unnecessary, the apparatus can be reduced in size.

In the present embodiment, the intervals between the ribs are configured to be equal in the conveyance direction and in the direction orthogonal to the conveyance direction, but this is merely an example. The height and interval of the ribs are not limited to a specific configuration as long as the above-described water droplet dispersion holding function is ensured. In other words, in addition to the shape described here, it is a shape suitable for holding water droplets due to condensation, maintaining surface tension that can prevent water droplets from falling due to gravity, and optimizing the amount of water to hold Other shapes may be used as long as the effect of natural drying can be enhanced.

[Variation of water drop holding shape]
FIG. 4 is a schematic diagram illustrating a modification of the configuration of the conveyance surface of the conveyance guide 41 in the present embodiment. 4A is a schematic perspective view of the transport guide 41, FIG. 4B is a view of the transport surface of FIG. 4A viewed from the front, and FIG. 4C is a cross-sectional view of the transport guide 41 viewed in the transport direction. As shown in FIG. 4, the water droplet holding shape may be a lattice shape (water droplet holding shape 81) extending between the adjacent paper passing ribs 41 </ b> A so that the short ribs obliquely intersect each other.

  The water droplet holding shape 81 in the present modification example is a rib 41D extending inclined from one side of the pair of paper passing ribs 41A toward the other side in the conveying direction, and inclined from the other side toward the upstream side in the conveying direction. And a rib 41E extending. Each of the ribs 41D and 41E is configured such that the height decreases as the distance from the connecting portion with the sheet passing rib 41A increases. Therefore, the height of the opening edge of the recess 281 formed by the paper passing rib 41A, the ribs 41D, 41E becomes lower as the distance from the paper passing rib 41A increases. Further, the recesses 281 having a relatively low height are arranged in the transport direction at a position apart from any of the sheet passing ribs 41A between the pair of sheet passing ribs 41A.

  As shown in FIG. 4B, in the lattice-shaped water droplet holding shape 81 in which the ribs 41D and 41E whose height is short with respect to the paper passing rib 41A obliquely intersect, the paper passing rib 41A and the ribs 41D and 41E are surrounded. A narrow-angle portion 81A is formed in the recessed portion 281 formed in this manner. Retention of water droplets by surface tension is formed by forming a narrow-angle portion 81A that is formed at an acute angle with respect to the corner portion of the other concave portion 281 (formed in a convex shape downward in the direction of gravity on the conveyance surface). The effect can be enhanced. Further, as shown in FIG. 4C, the recess 281 including the narrow-angle portion 81A is configured such that the bottom surface has a lower height than the other recesses, at least the other recesses disposed around. ing. With such a configuration, the surface tension in water droplet holding is increased, and the improvement of the water droplet holding effect can be aimed at.

(Example 2)
An image forming apparatus according to a second embodiment of the present invention will be described with reference to FIGS. 5A and 5B are schematic cross-sectional views showing a schematic configuration of an image forming apparatus according to Embodiment 2 of the present invention. FIG. 5A is a view when the image reading apparatus is in a closed position, and FIG. FIG. 6 is a view when the device is in an open position. As shown in FIG. 5, in the image forming apparatus according to the present embodiment, an image reading apparatus 60 that reads a document image is disposed above the apparatus main body 100. The image forming apparatus is of a cylinder discharge type that discharges the sheet 10 on which an image is formed in a discharge space 51 formed between the apparatus main body 100 and the image reading apparatus 60. The configuration of the image forming apparatus according to the present embodiment excluding the image reading device 60 is the same as that of the image forming apparatus according to the first embodiment, and a description thereof will be omitted.

  As described in the first embodiment, the sheet 10 discharged to the discharge tray 50 is taken out from the discharge space 51 by the user. In this embodiment, the image reading apparatus 60 is attached to the apparatus main body 100 by a hinge 70 so as to be opened and closed. When the paper 10 discharged into the discharge space 51 is a small size paper or the like, the paper is hidden under the image reading device 60 and is difficult for the user to see, and is shown in FIG. In this manner, the image reading device 60 is rotated upward to take out the paper 10.

The surface on the discharge space 51 side of the image reading device 60 is a surface facing the stacking surface on which the paper 10 is placed, and a conveyance surface 61 for guiding the paper 10 discharged from the apparatus main body 100 by the discharge roller pair 42 from above. Is formed. Similar to the conveyance guide 141 of the first embodiment, the conveyance surface 61 is provided with a plurality of sheet passing ribs 61A that guide the sheet 10 in parallel with the conveyance direction. Here, when the surface between the sheet passing ribs 61A is a flat surface, there is a concern about the same problem as the conveyance guide 41 of the conventional example of FIG. That is, when the user rotates the image reading device 60 upward in order to take out the paper 10, water droplets adhering to the conveyance surface 61 due to condensation stick to the side surface of the paper passing rib 61A, and the discharge tray 50 and the discharge space 51. There is a concern that it may fall on the discharged paper.

  6A and 6B are schematic diagrams illustrating a conveyance surface of the image reading apparatus in the image forming apparatus according to the second embodiment of the present invention. FIG. 6A is a schematic perspective view of the conveyance surface 61, and FIG. It is the figure which looked at the surface 61 from the front. In the present exemplary embodiment, the component having the conveyance surface 61 in the image forming apparatus corresponds to the conveyance path forming unit in the present invention.

  In this embodiment, the transport surface 61 is provided with three types of ribs, that is, a sheet passing rib 61A, a rib 61B, and a rib 61C. The sheet passing rib 61A is a rib that extends in the transport direction of the paper 10 on the transport surface 61, and is a rib that mainly exhibits a function of guiding the paper 10 in the transport direction. The rib 61B and the rib 61C are ribs that are bent in a convex shape toward the conveyance direction (a central portion protrudes in an inverted V shape) between a pair of paper passing ribs 61A arranged in a direction orthogonal to the conveyance direction. Form a shape. The rib 61B and the rib 61C form a water droplet holding shape 82 in the present embodiment together with the paper passing rib 61A.

[Water drop retention shape]
The rib 61B is inclined and extended toward the downstream side in the conveyance direction of the paper 10 from one of a pair of adjacent paper passing ribs 61A toward an intermediate point with the other. The rib 61C and the other end of the pair of paper passing ribs 61A extend from the other side to the downstream side in the conveying direction in an inclined manner. The rib 61B and the rib 61C are ribs having a height lower than that of the sheet passing rib 61A. Each of the ribs 61B and 61C is formed such that the height decreases as the distance from the connecting portion with the sheet passing rib 61A increases. Are connected to each other at the midpoint of A plurality of such pairs of the ribs 61B and the ribs 61C are provided between the pair of adjacent paper passing ribs 61 at intervals in the transport direction.

  Although not shown, in the plurality of ribs 61B and the ribs 61C arranged in the transport direction, the change in height of each rib is the same when viewed in the transport direction, and a pair of adjacent paper passing ribs 61A. The height of the rib is the lowest in the middle. In addition, the rib 61B and the rib 61C form a narrow-angle portion 82A that obliquely intersects the sheet passing rib 61A at the connecting portion with the sheet passing rib 61A.

  According to the water droplet holding shape 82 configured as described above, water droplets generated by condensation or the like can be effectively dispersed and held. For example, when the user rotates the image reading device 60 upward with respect to the apparatus main body 100 in order to take out the paper, water droplets adhering to the conveyance surface 61 move in the direction of gravity through the paper passing rib 61A. The water droplet holding shape 82 hinders. The water droplets whose movement is prevented are guided and held by the narrow-angle portion 82A through the rib 61B or the rib 61C. The amount of water droplets that cannot be held by the narrow-angle portion 82A is from the connecting portion side between the rib 61B and the rib 61C, which is separated from the paper passing rib 61A, before the height of the water droplet reaches the height of the paper passing rib 61A. Move to adjacent holding shape. In this manner, water droplets can be dispersedly held, and a large amount of water droplets can be prevented from falling on the paper 10 discharged to the discharge tray 50 or the discharge space 51 due to attachment at one place.

[Variation of water drop holding shape]
As the water droplet holding shape, unlike the water droplet holding shape 83 shown in FIG. 7, the ribs 61B and the tips of the ribs 61C (the portions where the height is the lowest) are not connected to each other, and are alternately in the direction along the paper passing rib 61A. The structure arrange | positioned may be sufficient. In this case, it is preferable that the tip portions of the rib 61B and the rib 61C overlap with each other when viewed in the transport direction. Thereby, the water droplet which moves to the gravity direction on the conveyance surface 61 can be stopped in the location where the front-end | tip part of the rib 61B and the rib 61C crosses.

(Example 3)
With reference to FIG. 8, an image forming apparatus according to Embodiment 3 of the present invention will be described. FIG. 8 is a schematic cross-sectional view showing a schematic configuration of an image forming apparatus according to Embodiment 3 of the present invention. The basic configuration of the image forming apparatus according to the present embodiment is the same as that of the first embodiment, but has a plurality of discharge trays for distributing the sheets discharged from the fixing device according to the purpose of use. Yes.

  As shown in FIG. 8, a second discharge tray 90 and a third discharge tray 91 are arranged above the discharge tray 50 so as to overlap each other with a stacking space therebetween. The number of discharge trays is not limited to the configuration of this embodiment. A second discharge conveyance surface 90A and a third discharge conveyance surface 91A for guiding the paper 10 from above are formed on the back side (lower surface) of each discharge tray 90, 91. By providing the water droplet holding shape of the first and second embodiments described above on these discharge and transport surfaces, the effect of preventing the adhesion of water droplets can be obtained as in the first and second embodiments. Since the configuration of the water droplet holding shape is the same as in the first and second embodiments, the description thereof is omitted.

  DESCRIPTION OF SYMBOLS 100 ... Image forming apparatus main body, 100A ... Image forming part, 41 ... Conveyance guide, 41A ... Paper passing rib, 41B ... Horizontal rib, 41C ... Vertical rib, 181 ... First recessed part, 182 ... Second recessed part, 61 ... Conveying surface , 80, 81, 82, 83 ... water droplet holding shape

Claims (25)

An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A recording material guide rib capable of guiding the recording material;
A water drop rib connected to the recording material guide rib and formed lower than the recording material guide rib,
The water drop rib is
The height decreases as the distance from the connecting portion with the recording material guide rib decreases, and the height of water droplets held in a plurality of recesses formed between the recording material guide rib reaches the height of the recording material guide rib. An image forming apparatus, characterized in that, before, a water droplet can be moved to another concave portion adjacent to the concave portion.   A plurality of the water droplet ribs are provided side by side in the recording material conveyance direction, and the height variation of the plurality of water droplet ribs when viewed in the conveyance direction is the same. Item 2. The image forming apparatus according to Item 1. The water drop rib is
A lateral rib extending in a direction orthogonal to the direction in which the recording material guide rib extends;
Vertical ribs extending parallel to the recording material guide ribs;
The image forming apparatus according to claim 1, further comprising:   The image forming apparatus according to claim 1, wherein the recording material guide rib extends along a conveyance direction of the recording material. The path forming unit is provided in an image reading apparatus that is rotatably attached to the apparatus main body of the image forming apparatus,
5. The recording material guide rib according to claim 1, wherein a difference between an upstream height and a downstream height in a direction in which the recording material guide rib extends changes due to rotation of the image reading device. The image forming apparatus according to claim 1. Among a plurality of recesses formed on said the transport path facing surface of the front Symbol path forming unit, a recess formed between the water droplet rib and the recording material guide ribs, adjacent a front type recording medium guide ribs The image forming apparatus according to claim 1, wherein a bottom is deeper than a concave portion not to be formed.   Among the plurality of recesses, at least the plurality of recesses not adjacent to the recording material guide rib have the same bottom surface area, and the side surface height changes so as to become farther away from the connection portion. The image forming apparatus according to claim 1.   The image forming apparatus according to claim 7, wherein the plurality of concave portions are arranged at equal intervals in a conveyance direction of the recording material and a direction orthogonal to the conveyance direction.   The plurality of recesses are arranged at equal intervals in two directions that are both inclined with respect to the conveyance direction of the recording material and the direction orthogonal to the conveyance direction and orthogonal to each other. The image forming apparatus according to claim 7.   10. The image according to claim 7, wherein the height of the side surface changes in a direction perpendicular to the conveyance direction of the recording material so as to decrease as the distance from the connection portion increases. Forming equipment. An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A plurality of first ribs extending in parallel with each other in the recording material conveyance direction;
A plurality of second ribs extending in a direction lower than the first rib and different from the transport direction;
A plurality of third ribs that are lower than the first ribs and extend parallel to each other in the transport direction;
With
The image forming apparatus according to claim 1, wherein the second rib is connected to the first rib, and the height decreases as the distance from the connecting portion increases.   The plurality of second ribs are provided side by side in the transport direction, and the change in height of the plurality of second ribs when viewed in the transport direction is the same as each other. The image forming apparatus according to 11. An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A plurality of first ribs extending in parallel with each other in the recording material conveyance direction;
A plurality of second ribs extending in a direction lower than the first rib and different from the transport direction;
With
The image forming apparatus according to claim 1, wherein the second rib is connected to the first rib, and the height decreases as the distance from the connecting portion increases.   The plurality of second ribs are provided side by side in the transport direction, and the change in height of the plurality of second ribs when viewed in the transport direction is the same as each other. The image forming apparatus according to 13.   The image forming apparatus according to claim 13, wherein the plurality of second ribs extend in a lattice shape between the plurality of first ribs.   The image forming apparatus according to claim 13, wherein the second rib extends from the connecting portion toward a downstream side in the transport direction.   The image according to claim 13 or 14, wherein the second rib is bent and extended so as to be convex toward the downstream side in the transport direction between the plurality of first ribs. Forming equipment.   The plurality of second ribs connected to one of the first ribs adjacent to each other and the plurality of second ribs connected to the other are alternately arranged in the transport direction. The image forming apparatus according to claim 13, wherein the image forming apparatus is an image forming apparatus. Among a plurality of recesses formed before SL on the the conveying path facing surface of the path forming unit, a recess formed between the first rib and said second rib, adjacent to the front Symbol first rib The image forming apparatus according to any one of claims 11 to 18, wherein a bottom is deeper than a concave portion not to be formed. An image forming unit for forming a toner image on a recording material;
A path forming unit that forms a transport path for transporting the recording material;
In an image forming apparatus comprising:
The path forming unit is
A recording material guide portion that is provided on a surface facing the conveyance path and guides the recording material;
A plurality of recesses for holding water droplets provided on a surface facing the transport path, wherein a plurality of recesses having a height of a limitable amount of water drops that is lower than the height of the recording material guide part;
Have
The image forming apparatus according to claim 1, wherein a limit amount of the concave portion that can hold a water droplet decreases with distance from the recording material guide portion.   21. The image forming apparatus according to claim 20, wherein the concave portion has a narrow angle portion in which two side surfaces sandwiching the corner portion form an acute angle.   The image forming apparatus according to claim 20 or 21, wherein in the plurality of concave portions, the concave portion adjacent to the recording material guide portion has a deeper bottom than the other concave portions. Before Ki凹 portion is a surface facing the transport path of the path forming unit, according to claim 1-10, characterized in that formed on the surface opposite to the surface for mounting the recording material in the transport path the image forming apparatus according to any one of 19-22. The image forming apparatus according to any one of claims 1 to 22, further comprising a fixing unit for fixing the toner image formed on the recording material to the recording material. A fixing unit for fixing the toner image formed on the recording material to the recording material;
Before Ki凹 portion, even on the surface facing the transport path of the path forming unit, any one of the claims 1～10,19, characterized in that it is formed above the fixing part The image forming apparatus described in 1.

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