JP7130187B2 - Sheet conveying device, image reading device and image forming device - Google Patents

Description

The present invention relates to a sheet conveying device that conveys a sheet, and an image reading apparatus and an image forming apparatus having the sheet conveying device.

2. Description of the Related Art As a sheet conveying apparatus that conveys a sheet, for example, a document conveying apparatus that is mounted in an image reading apparatus such as a scanner and conveys a document is known.

2. Description of the Related Art In recent years, in order to save space in an image reading apparatus, a reading sensor such as a CIS (Contact Image Sensor) is often used. Since this type of reading sensor has a shallow depth of focus, in order to prevent the document from being too far away from the reading sensor, a facing member having an arc-shaped outer peripheral surface, such as a roller, is arranged at a position facing the reading sensor. The space between the document and the reading sensor is managed by the opposing member (see Patent Document 1 below).

By the way, some documents conveyed by the document conveying device have bent or curled leading ends. When such a folded or curled document is conveyed, first, as shown in FIG. be postponed. However, when the leading edge of the document S passes through the position C where the gap between the opposing member 100 and the reading sensor 200 is the smallest, the leading edge of the document S is bent again by the restoring force as shown in FIG. The bent distal end may enter between the opposing member 100 and the guide member 300 on the downstream side. As a result, the document may not be conveyed satisfactorily, for example, the document may be jammed.

In order to solve the above problems, the present invention provides a conveying means for conveying a sheet, a structure arranged along a conveying path along which the sheet is conveyed, and a gap for allowing the sheet to pass through the structure. A sheet conveying device comprising: a facing member having an arc-shaped outer peripheral surface arranged with a gap; and a guide member that guides a surface of the sheet on the side of the facing member on the downstream side of the facing member in the sheet conveying direction, The end portion of the guide member on the upstream side in the sheet conveying direction is positioned downstream in the sheet conveying direction from the position of the structure where the gap between the opposing member and the structure is the narrowest so as to be in contact with the outer peripheral surface of the opposing member. The sheet is arranged on the side of the facing member from the imaginary straight line extending to the side, the sheet is a sheet with a bent tip, and the gap between the facing member and the structure is the narrowest. A distance from the position of the body to the end of the guide member on the upstream side in the sheet conveying direction is set shorter than the length of the bent leading end .

According to the present invention, it is possible to prevent the leading edge of the sheet from entering between the opposing member and the guide member, and the sheet can be conveyed satisfactorily.

1 is a diagram showing an embodiment of an image forming apparatus provided with an image reading device according to the present invention; FIG. FIG. 4 is a diagram showing an image reading unit; FIG. 2 is a diagram showing a document conveying device; FIG. 2 is an enlarged view of a second document reading device and its peripheral structure; FIG. 4 is a diagram showing a state in which a part of the document transport path is opened; FIG. 10 is a diagram showing the behavior of the document before the bending position of the document passes the image reading position; FIG. 10 is a diagram showing the behavior of the document when the document bending position reaches the image reading position; FIG. 10 is a diagram showing the behavior of the document after the bending position of the document has passed the image reading position; FIG. 10 is a diagram for explaining the relationship between the distance from the image reading position to the upstream end of the lower guide plate and the length of the bent leading edge of the document; FIG. 10 is a diagram for explaining the relationship between the distance between the guide surface of the lower guide plate and the second reading section and the length of the bent leading edge of the document; It is a perspective view of a lower guide plate. FIG. 10 is a diagram showing the behavior of a document in a conventional configuration; FIG. 10 is a diagram showing the behavior of a document in a conventional configuration;

The present invention will be described below with reference to the accompanying drawings. In addition, in each drawing for explaining the present invention, constituent elements such as members and constituent parts having the same function or shape are given the same reference numerals as much as possible, and once explained, the explanation will be repeated. omitted.

FIG. 1 is a diagram showing an embodiment of an image forming apparatus equipped with an image reading device according to the present invention.

The image forming apparatus 1 shown in FIG. 1 is an electrophotographic color laser printer. In addition to the printer, the present invention may be a copier, a facsimile machine, or a multifunction machine having two or three of these functions. Also, the image forming apparatus is not limited to a color image forming apparatus, and may be a monochrome image forming apparatus. As an image forming method, in addition to the electrophotographic method, it is also possible to use an inkjet method or the like.

As shown in FIG. 1 , the image forming apparatus 1 includes an image reading device 2 , an image forming section 3 and a paper feeding section 4 .

A plurality of paper feed cassettes 5 are provided in the paper feed unit 4 . Each paper feed cassette 5 accommodates paper as a recording medium. The paper feed unit 4 includes a feed roller 6 for feeding paper from each paper feed cassette 5 , a separation roller 8 for separating the fed paper and feeding it to a paper feed path 7 , and a paper feed path 7 for feeding paper. Conveying rollers 9 for conveying are provided.

The image forming section 3 includes four image forming units 10K, 10Y, 10M, and 10C, an optical writing device 11, a transfer device 12, a timing roller pair 13, a fixing device 14, and a paper discharge roller pair 15. is provided.

The four image forming units 10K, 10Y, 10M, and 10C have the same configuration except that they contain developers of different colors of black, yellow, magenta, and cyan corresponding to color separation components of a color image. . Specifically, each of the image forming units 10K, 10Y, 10M, and 10C includes a drum-shaped photoreceptor 16 as an image carrier, a charging device 17 that charges the surface of the photoreceptor 16, and a It is composed of a developing device 18 that supplies toner as a developer to form a toner image, a cleaning device 19 that cleans the surface of the photoreceptor 16, and the like. In FIG. 1, only the image forming unit 10K that forms a black image is denoted by the photosensitive member 16, the charging device 17, the developing device 18, and the cleaning device 19, and the other image forming units 10Y and 10M. , 10C are omitted.

The transfer device 12 includes an endless intermediate transfer belt 20 stretched by a plurality of rollers, four primary transfer rollers 21 for transferring the toner images on the photoreceptors 16 to the intermediate transfer belt 20, and the intermediate transfer belt 20. It is composed of a secondary transfer roller 22 and the like for transferring the toner image transferred thereon to the paper.

The image reading device 2 includes a document conveying device 23 as a sheet conveying device for conveying a document, and an image reading section 24 as image reading means for reading image information of the conveyed document. Note that the image reading device 2 is not installed in the image forming apparatus 1, but is installed in a different location apart from the image forming apparatus 1, and can communicate with the image forming apparatus 1 by wire or wirelessly. can be anything.

A printing operation of the image forming apparatus according to the present embodiment will be described with reference to FIG.

When there is an instruction to start the printing operation, the photosensitive member 16 is rotationally driven in each of the image forming units 10K, 10Y, 10M, and 10C, and the charging device 17 charges the surface of the photosensitive member 16 to a uniform high potential. Then, the optical writing device 11 exposes the surface of each photoreceptor 16 based on the image information of the document read by the image reading device 2 or the print information instructed to print from the terminal, thereby exposing the exposed portion. potential is lowered to form an electrostatic latent image. Toner is supplied from the developing device 18 to the electrostatic latent image, and a toner image is formed on each photosensitive member 16 .

When the toner images formed on the photoreceptors 16 reach the position (primary transfer nip) of the primary transfer roller 21 as each photoreceptor 16 rotates, they are transferred onto the rotating intermediate transfer belt 20 so as to overlap one another. be done. Then, the toner image transferred onto the intermediate transfer belt 20 is conveyed to the position (secondary transfer nip) of the secondary transfer roller 22 as the intermediate transfer belt 20 rotates, and transferred to the paper. This paper is supplied from the paper feed section 4 . After being temporarily stopped by the pair of timing rollers 13, the paper supplied from the paper feeding unit 4 is conveyed in time with the timing at which the toner image on the intermediate transfer belt 20 reaches the secondary transfer nip. Thus, a full-color toner image is carried on the paper. After the toner image is transferred, the toner remaining on each photoreceptor 16 is removed by each cleaning device 19 .

The paper onto which the toner image has been transferred is conveyed to the fixing device 14 , and the toner image is fixed on the paper by the fixing device 14 . Thereafter, the paper is discharged outside the apparatus by the paper discharge roller pair 15, completing a series of printing operations.

Next, based on FIG. 2, the image reading section 24 will be described in detail.

As shown in FIG. 2, the image reading unit 24 includes a first carriage 31 carrying a light source and a mirror member, a second carriage 32 carrying a mirror member, an imaging lens 33, and an imaging unit 34. there is These constituent members are arranged inside the body frame 24 a of the image reading section 24 . A slit glass 35 and a platen glass 36 are provided on the body frame 24 a of the image reading section 24 . Between the slit glass 35 and the platen glass 36, an abutment member 37 is provided for abutting and positioning a fixed document placed on the platen glass 36. As shown in FIG.

The first carriage 31 and the second carriage 32 are configured to be reciprocally movable in the sub-scanning direction (horizontal direction in FIG. 2). Here, the first carriage 31 and the second carriage 32 move in the sub-scanning direction at a speed ratio of 2:1, for example. Due to this moving speed relationship, even if the first carriage 31 and the second carriage 32 move, the optical path length from the document surface to the imaging lens 33 does not change.

The first carriage 31 has a light source 38a and a first mirror member 38b. The second carriage 32 also has a second mirror member 39a and a third mirror member 39b.

The imaging lens 33 converges and forms an image on the imaging unit 34 of the reflected light from the document incident through the mirror members 38b, 39a, and 39b. The imaging unit 34 is composed of an imaging element such as a CCD, and photoelectrically converts a reflected light image of the document imaged through the imaging lens 33 to output an analog image signal as a read image.

When reading the surface image of the document (moving document) conveyed by the document conveying device 23, the first carriage 31 is moved to the image reading position (the position indicated by the solid line in FIG. 2) immediately below the slit glass 35 and stopped. Let

Then, the original is conveyed onto the slit glass 35 by the original conveying device 23 , and the first carriage 31 illuminates the original passing over the slit glass 35 with illumination light from the light source. Reflected light transmitted through the slit glass 35 and reflected by the document passes through each mirror member mounted on the first carriage 31 and the second carriage 32 and forms an image on the imaging unit 34 by the imaging lens 33 to form a read image. (image information). The read image read by the imaging unit 34 is output to the optical writing device 11 .

On the other hand, when reading a document (fixed document) placed on the platen glass 36 while being abutted against the abutting member 37, the first carriage 31 and the second carriage 32 are moved in the horizontal direction (sub-scanning direction) in FIG. direction). In the process of moving the carriages 31 and 32, the light source irradiates the fixed document with light, and the mirror members mounted on the carriages 31 and 32 reflect the reflected light from the fixed document. The reflected light is imaged by the image forming lens 33 and read by the imaging unit 34 . The read image thus read is output to the optical writing device 11 in the same manner as in the case of the moving original.

Subsequently, based on FIG. 3, the document conveying device 23 will be described in detail.
In the following description of the document conveying device 23, the downstream side in the document conveying direction will be referred to as "downstream side" and the upstream side in the document conveying direction will be referred to as "upstream side".

As shown in FIG. 3, the document conveying device 23 includes a document tray 41 as a document table on which the document S is placed, a document conveying section 42 including various rollers and the like, and a stacker for stacking the document S after image reading. A paper tray 43 is provided.

The document tray 41 is disposed so that the document conveying portion 42 side is the leading edge side of the document S, the leading edge side is downward, and the trailing edge side is upward. The document tray 41 is divided into a front-end document tray 41A and a rear-end document tray 41B, and the leading end of the front-end document tray 41A tilts downward according to the thickness of the bundle of documents S around a shaft 41C as a rotation center. It's like The document tray 41 has a side guide plate 44 for positioning the document S toward the document conveying section 42 in the horizontal direction perpendicular to the feeding direction.

The side guide plate 44 is a pair of plates that can be relatively moved toward or away from the document tray 41 so that the center of the document S in the width direction is aligned, or one side of the document S is attached to one edge of the document tray 41 . may be arranged such that only the other edge portion is movable while the other edge portion is brought into contact with the other edge portion.

The document conveying section 42 is covered with a cover 45 that can be opened and closed at least above. The cover 45 has a paper feed port 45a so that the leading edge of the document S faces the inside of the cover. The cover 45 covers the upper end of the leading end side document tray 41A so that the leading end of the leading end side document tray 41A is located inside the paper feed port 45a. The document conveying section 42 forms a document conveying path 46 by ribs or the like formed on the cover 45 or the like in a range from the paper feed port 45 a to the paper discharge port 45 b above the paper discharge tray 43 .

Further, the document conveying device 23 has a set filler 47 that rotates when the document S is placed on the upper end of the leading end side document tray 41A at the upstream end on the paper feed port 45a side with respect to the document transport direction of the document S. , a document set sensor 72 for detecting whether or not the document S is placed on the document tray 41 by detecting the lowermost portion of the movement locus of the leading end of the set filler 47, and an inner side of the paper feed port 45a. , and a paper feed belt 49 and a reverse roller 50 that are arranged to face each other with the document transport path 46 interposed therebetween.

The pickup roller 48 picks up several sheets (ideally one sheet) of the documents S stacked on the document tray 41 at the contact position.

The paper feed belt 49 rotates along the document feeding direction. The reverse roller 50 rotates in a direction opposite to the rotational movement direction of the paper feed belt 49 when a plurality of sheets of the originals S are about to be multi-fed, thereby suppressing multi-feeding of the originals S. FIG.

A home position below the leading edge of the leading edge side document tray 41A is a state in which no document S is placed on the document tray 41, that is, a state in which the pickup roller 48 is in direct contact with the leading edge side document tray 41A. A home position sensor 73 is provided for detection.

The document transport section 42 has a plurality of transport roller pairs 51 to 55 as transport means for transporting the document S. As shown in FIG. The number and locations of the conveying roller pairs 51 to 55 are determined according to, for example, the route design of the document conveying path 46, the length of the document S in the document conveying direction of the minimum size allowed by the document conveying device 23, and the like. is optional.

In addition, the transport roller pair 51 arranged adjacent to the downstream side of the paper feed belt 49 abuts the leading edge of the fed document S in accordance with the driving timing of the pickup roller 48 to correct the skew transport. It has a leading end aligning function for pulling out and conveying the original document S.

The document conveying unit 42 includes a first reading roller 56 arranged to face the upper part of the slit glass 35 to read the image of the document S, and a first reading roller 56 arranged immediately upstream of the discharge port 45b to discharge the document S. It also has a paper discharge roller pair 57 that discharges the paper toward the paper discharge tray 43 from the paper outlet 45b.

The first reading roller 56 is urged toward the slit glass 35 by an urging member such as a coil spring, and brings the original S into close contact with the slit glass 35 while conveying the original.

A second document reading device 58 for reading the back side image of the document S is arranged between the two pairs of transport rollers 54 and 55 arranged downstream of the first reading roller 56 .

The second document reading device 58 includes a second reading section 59 as image reading means for reading the back side image of the document S, and a facing member arranged to face the second reading section 59 with the document transport path 46 interposed therebetween. It has a second reading roller 60 and bearings 61 that support the ends of the second reading roller 60 .

The second reading section 59 is composed of a contact image sensor (CIS), and reads the back side image of the document S after the front side image of the document S has been read by the imaging section 34 of the image reading section 24 .

The second reading roller 60 suppresses floating of the document S in the second reading section 59 and also serves as a white reference section for obtaining shading data in the second reading section 59 . The second reading roller 60 is formed longer than the width of the document so that the reading image quality does not change depending on the size of the document. Even if the outer peripheral surface (white reference portion) of the second reading roller 60 becomes dirty with dust or scratches, the second reading roller 60 acquires shading data while the second reading roller 60 rotates. can be obtained, and stable shading data can be obtained. It should be noted that the document S passes through the second reading section 59 when the back side image of the document S is not read.

The bearing 61 adjusts the distance between the second reading unit 59 and the document S to a depth of focus that does not impair the image quality, and the readable distance is an appropriate distance at which the second reading unit 59 can read the image of the document S. is configured to keep

In addition, the document conveying unit 42 has a proper paper feed position sensor 74, an abutting sensor 75, a document width sensor 76, a reading entrance sensor 77, a registration sensor 78, and a paper ejection sensor 79, which are arranged to detect the document S from the upstream side in the document S conveying direction to the downstream side. They are arranged side by side in this order.

The paper feeding proper position sensor 74 is arranged above the leading end of the leading end side document tray 41A and detects the presence or absence of the document S being transported in the document transport path 46 . The proper feeding position sensor 74 detects whether or not the front end portion of the document S placed on the document mounting surface in the feeding direction is held at the proper feeding position at an appropriate height.

The abutment sensor 75 is arranged between the paper feed belt 49 and the conveying roller pair 51 on the one downstream side. When the abutment sensor 75 detects the leading edge and the trailing edge of the document S, the length of the document S in the transport direction is determined from motor pulses corresponding to the transport distance.

The document width sensor 76 is arranged between the first and second conveying roller pairs 51 and 52 from the upstream side. The document width sensor 76 has a plurality of light-emitting elements arranged along the width direction of the document S, and a light-receiving element arranged at a position facing the light-emitting elements with the document transport path 46 interposed therebetween. The width of the document S is determined based on the detection result of the light receiving element.

The reading entrance sensor 77 is arranged between the second and third conveying roller pairs 52 and 53 from the upstream side, the registration sensor 78 is arranged between the third and fourth conveying roller pairs 53 and 54, The paper ejection sensor 79 is arranged between the fourth conveying roller pair 54 and the second reading section 59 . These sensors 77, 78, and 79 are used for conveying control such as the conveying distance and conveying speed of the document S, jam detection, and the like.

FIG. 4 is an enlarged view of the second document reading device 58 and its peripheral structure.

As shown in FIG. 4 , in the second document reading device 58 , the lower portion of the document transport path 46 as a boundary is integrally configured as a movable unit 80 that swings up and down about a rotation shaft 63 . there is Specifically, the movable unit 80 includes the second reading roller 60, the lower rollers 54b, 55b, and 57b of the fourth and fifth conveying roller pairs 54 and 55 and the paper discharge roller pair 57, and the front surface of the document. a plurality of lower guide plates 64b and 65b as guide members for guiding (the surface on the side of the second reading roller 60); a bearing 61 supporting the shaft 60a of the second reading roller 60; A spring 66 is provided as an urging member that urges the reading unit 59 in a direction to approach it. These are provided integrally with the unit frame 80 a of the movable unit 80 .

When the movable unit 80 is rotated downward about the rotation shaft 63, as shown in FIG. 2. It moves away from the reading surface 59a of the reading section 59, the upper rollers 54a, 55a, 57a, and the upper guide plates 64a, 65a, thereby partially opening the document transport path 46. FIG. Also, at this time, the second document reading device 58 is in an open state away from the platen glass 36 .

Such an opening operation of the movable unit 80 is performed by the user when foreign matter such as dust or paper dust adheres to the reading surface 59a of the second reading unit 59, or when a document jam occurs in the document transport path 46. done as appropriate. When the user opens the movable unit 80, a part of the document transport path 46 including the reading surface 59a is opened, so that the reading surface 59a can be easily cleaned and jammed.

After cleaning the reading surface 59a and clearing the jam, the movable unit 80 is rotated upward from the state shown in FIG. When the lower guide plates 64b and 65b approach or contact the reading surface 59a of the second reading unit 59, the upper rollers 54a, 55a and 57a, and the upper guide plates 64a and 65a (positions shown in FIG. 4). placed. At this time, the second reading roller 60 is urged toward the second reading section 59 by the urging force of the spring 66, and the bearing 61 comes into contact with the second reading section 59, so that the reading surface 59a is properly rotated. maintained at a reasonable reading distance.

By the way, as shown in FIG. 5 , in the open state in which the document transport path 46 is partially opened, the second reading roller 60 is arranged downstream of the second reading roller 60 by the biasing force of the spring 66 . It is held in contact with the lower guide plate 65b. On the other hand, as shown in FIG. 4, in the closed state in which the document transport path 46 is closed, the bearing 61 that supports the second reading roller 60 contacts the second reading unit 59, thereby causing the second reading roller 60 to move. , a gap is generated between the second reading roller 60 and the upstream end of the lower guide plate 65b on the downstream side. Therefore, if the leading edge of the document should enter this gap, problems such as document jam may occur. In particular, when the leading edge of the document is bent, if the document is conveyed so that the bending direction of the leading edge faces the direction of the gap, the leading edge of the document is likely to enter the gap.

Therefore, in the present embodiment, the following countermeasures are taken so as to prevent the leading edge of the folded document from entering.

First, the behavior of the document being conveyed will be described. As shown in FIG. 6 , when the document S with the leading edge A bent is conveyed between the second reading roller 60 and the second reading section 59 , the document S reaches the outer peripheral surface of the second reading roller 60 . By being guided along, the bending of the tip A is temporarily extended. In this way, the bent state is extended until the bending position B of the leading end A passes through the image reading position C where the width between the second reading roller 60 and the second reading section 59 is the narrowest. Continued. The image reading position C corresponds to the position of the optical axis 59b of the second reading section 59, and is the position where the second reading section 59 reads image information.

Thereafter, as shown in FIG. 7, when the bending position B reaches the image reading position C, the bending of the document S starts to return. Here, the position of the leading edge A of the document S when the bending recovery is started is such that it overlaps with the imaginary straight line L extended downstream from the image reading position C so as to be in contact with the outer peripheral surface of the second reading roller 60 . position.

Therefore, in view of such behavior of the leading edge A of the document S, in order to prevent the leading edge A of the document S from entering the gap between the second reading roller 60 and the lower guide plate 65b, at least bending It is necessary that the lower guide plate 65b can receive the leading edge A of the document S when the return of the document S starts. Therefore, in the present embodiment, as shown in FIG. 7, the upstream end portion 650 of the lower guide plate 65b is arranged at the bending recovery start position, that is, closer to the second reading roller 60 than the imaginary straight line L. .

As a result, even when the bending position B of the document S reaches the image reading position C and the recovery of the bending is started, the leading end A of the document S can be brought into contact with the lower guide plate 65b. can be suppressed from entering the gap between the lower guide plate 65 b and the second reading roller 60 .

Further, as shown in FIG. 8, after the bending position B passes the image reading position C, there is a tendency that the bending is further restored. Since it is downstream of the intersection point D with the lower guide plate 65b, the document S is conveyed without entering the gap between it and the second reading roller 60. As shown in FIG.

As described above, in the present embodiment, the upstream end portion 650 of the lower guide plate 65b is arranged closer to the second reading roller 60 than the bending return start position (virtual straight line L), so that the leading end portion A is bent. Even when the document S is conveyed, it is possible to suppress the entry of the document S into the gap between the second reading roller 60 and prevent the occurrence of a document jam. It is possible to avoid the occurrence of defects.

Further, as shown in FIG. 9, the distance M from the image reading position C to the upstream end portion 650 of the lower guide plate 65b is the length of the bent leading end portion A of the document S (the length of the side extending in the transport direction). ) is preferably set shorter than N. By setting in this way, the document S is much less likely to enter the gap between the second reading roller 60 and the lower guide plate 65b.

For example, when a document is stapled by a binding device that can be attached to the image forming apparatus 1, the binding process is performed at a position 4 mm from the edge of the document, and generally at a position 4 to 6 mm from the edge of the document. Therefore, when a fold is formed with the stapled position as a reference, the length N of the bent leading edge A of the document S is usually 4 to 6 mm. Therefore, as a countermeasure against paper jams of the stapled document S, the distance M from the image reading position C to the upstream end 650 of the lower guide plate 65b is set shorter than 4 mm of the stapling position. It is possible to effectively prevent the document S from entering the gap between the second reading roller 60 and the second reading roller 60 . Note that the present invention is not limited to documents with folds formed at the stapled position, but can also be applied to documents with folds or curls for other reasons. is.

Further, as shown in FIG. 10, the distance T between the guide surface of the lower guide plate 65b and the second reading unit 59 in the direction intersecting the document conveying surface (sheet conveying surface) is It is desirable that the length of the leading end A (the length of the side extending in the conveying direction) is set shorter than N. By setting in this way, the document S can be guided in a state in which the bending is extended, and the document S can be smoothly conveyed.

In this embodiment, the lower guide plate 65b parallel to the facing surface of the second reading unit 59 has an inclined surface 651 (see FIG. 10) that is inclined away from the second reading unit 59 toward the upstream end 650 thereof. The inclined surface 651 guides the leading edge of the document S to the downstream side. The inclination angle θ of the inclined surface 651 can be set arbitrarily. In particular, it is preferable that the imaginary extension line of the inclined surface 651 is above the center of the shaft 60 a of the second reading roller 60 .

Further, in this embodiment, when the movable unit 80 is opened, the second reading roller 60 comes into contact with the lower guide plate 65b (see FIG. 5). It is desirable to provide a plurality of ribs 652 on the portion to improve the strength of the lower guide plate 65b.

As described above, the embodiments of the present invention have been described by taking the document conveying device used in the image reading apparatus as an example, but the present invention is not limited to the above-described embodiments. The present invention can be widely applied to a sheet conveying apparatus that conveys sheets other than originals, such as a sheet conveying apparatus that conveys sheets (recording media) sent out from a paper feed cassette. Also, a device that conveys a sheet between a structure other than the second reading unit 59 and a facing member that faces the structure may be used. Accordingly, the present invention provides a conveying means for conveying a sheet, a structure arranged along a conveying path along which the sheet is conveyed, and an arcuate structure arranged with a gap for allowing the sheet to pass through the structure. Any sheet conveying device that includes an opposing member having an outer peripheral surface and a guide member that guides the surface of the sheet on the side of the opposing member on the downstream side of the opposing member in the sheet conveying direction can be applied.

REFERENCE SIGNS LIST 1 image forming apparatus 2 image reading apparatus 3 image forming section 23 document conveying apparatus (sheet conveying apparatus)
24 image reading unit 46 document conveying path 51 pair of conveying rollers (conveying means)
52 conveying roller pair (conveying means)
53 conveying roller pair (conveying means)
54 conveying roller pair (conveying means)
55 conveying roller pair (conveying means)
59 second reading unit (structure, image reading means)
60 Second reading roller (facing member)
65b Lower guide plate (guide member)
650 upstream end (end on the upstream side in the sheet conveying direction)
651 Inclined surface A Leading edge C Image reading position S Document (sheet)
θ tilt angle

Japanese Unexamined Patent Application Publication No. 2015-27070

Claims (7)

a conveying means for conveying the sheet;
a structure arranged along a transport path along which the sheet is transported;
a facing member having an arc-shaped outer peripheral surface disposed with a gap for allowing the sheet to pass through the structure;
a guide member that guides the surface of the sheet on the side of the facing member on the downstream side of the facing member in the sheet conveying direction;
In a sheet conveying device comprising
The end of the guide member on the upstream side in the sheet conveying direction is arranged in the sheet conveying direction so as to be in contact with the outer peripheral surface of the opposing member from the position of the structure where the gap between the opposing member and the structure is the narrowest. arranged on the opposing member side of the imaginary straight line extending downstream ,
The sheet is a sheet with a bent tip,
The distance from the position of the structure where the gap between the opposing member and the structure is the narrowest to the end of the guide member on the upstream side in the sheet conveying direction is longer than the length of the bent tip end. A sheet conveying device characterized by being set short . a conveying means for conveying the sheet;
a structure arranged along a transport path along which the sheet is transported;
a facing member having an arc-shaped outer peripheral surface disposed with a gap for allowing the sheet to pass through the structure;
a guide member that guides the surface of the sheet on the side of the facing member on the downstream side of the facing member in the sheet conveying direction;
In a sheet conveying device comprising
The end of the guide member on the upstream side in the sheet conveying direction is arranged in the sheet conveying direction so as to be in contact with the outer peripheral surface of the opposing member from the position of the structure where the gap between the opposing member and the structure is the narrowest. arranged on the opposing member side of the imaginary straight line extending downstream,
A sheet conveying device, wherein a distance between the guide member and the structure in a direction intersecting a sheet conveying surface is set shorter than a length of a bent tip portion of the sheet. 2. A sheet conveying apparatus according to claim 1 , wherein a distance between said guide member and said structure in a direction intersecting a sheet conveying surface is set shorter than a length of a bent leading edge of said sheet. the guide member has an inclined surface that is inclined away from the structure toward an upstream end in the sheet conveying direction;
4. The sheet conveying device according to any one of claims 1 to 3, wherein the inclined surface has an inclination angle of 90[deg.] or less. a document conveying device for conveying a document;
an image reading means for reading image information of a document conveyed by the document conveying device;
In an image reading device comprising
An image reading apparatus comprising the sheet conveying device according to any one of claims 1 to 4 as the document conveying device. 6. The image reading apparatus according to claim 5, wherein said image reading means is arranged to read image information on the back side of said document. an image reading device according to claim 5 or 6;
an image forming unit that forms an image on a recording medium based on the image information read by the image reading device;
An image forming apparatus comprising:

Images