JP3134773B2 - Document reading device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading device used as an image input device in a copying machine, a scanner, or the like, and more particularly, to a document reading device that reads an image while moving a document sheet.

[0002]

2. Description of the Related Art Conventionally, there are a document reading apparatus of a type for reading an image while fixing a document, and a method for reading an image while moving a document sheet.

The former method is generally called a platen method, and a document reading apparatus based on this method is, for example, a platen glass on which a document sheet is placed, and a rotatable fixed above the platen glass. Platen cover, an illumination lamp movably disposed below the platen glass, and a CC in which a large number of photoelectric conversion elements are arranged.
D sensor and an optical element such as a mirror for inputting the reflected light from the original to the CCD sensor. By outputting image information from the CCD sensor while moving the illumination lamp, the original image of the original paper can be converted. Reading.

On the other hand, the latter method is generally called Const
A document reading apparatus based on the ant velocity transport method (hereinafter referred to as CVT method) includes, for example, a document tray on which document sheets are placed, a document discharge tray from which document sheets are discharged, and a document tray. And a reading glass disposed along the document transport path, and a reading glass disposed on the opposite side of the reading glass from the document transport path. And a CCD sensor arranged side by side with the illumination lamp. The image information is output from the CCD sensor while moving the original sheet, thereby reading the original image of the original sheet. Hereinafter, these read images are referred to as read images.

In these document reading apparatuses, in order to read the image of the document, that is, it is necessary to pass the focal point of the CCD sensor so that the reflected light from the document paper forms an image on the CCD sensor. The platen glass and the reading glass function as a reference plate. In the following description, a side surface of the reading glass or the like on the side of the document conveying path through which the irradiation light of the illumination lamp or the light reflected by the document passes is referred to as a reading surface of the reading glass or the like.

However, in the original reading apparatus, when the correction liquid or the ink for a ball-point pen is placed on an original tray or the like without being fixed and the reading is started, the unfixed material is read. It adheres to glass etc. If the unfixed material adheres to the reading surface of the reading glass or the like, light is blocked by the unfixed material, so that a black point or white spot occurs in the read image. In particular, in a CVT type document reading apparatus,
If the unfixed material adheres to the reading surface, the entire image corresponding to the unfixed material cannot be read, resulting in black streaks or linear image omissions. Deterioration was not negligible.

In particular, in the CVT type document reading apparatus, since the image is read while the document is fed without being fixed, the mutual positional relationship between the document sheet and the focal position cannot be sufficiently stabilized. In addition, the document image cannot be read with sufficient image quality because the feeding speed of the document sheet at the focal position cannot be sufficiently stabilized. Note that these problems are caused, for example, as a result of the original paper becoming skewed.

Further, in the above document reading apparatus, when reading an image on a transparent or translucent document sheet such as tracing paper, the irradiation light of the illumination lamp passes through the document sheet. The background may be covered. Note that this phenomenon is generally called show-through.

Therefore, conventionally, in order to solve these problems, a flat plate (for example, a platen cover) is disposed facing the reading glass or the like.
There has been proposed a technique in which a paper feed roll is provided by being pressed against the reading glass.

However, when the former flat plate is used in a CVT type document reading apparatus, the irradiation light transmitted through the document sheet is reflected to prevent show-through, or the mutual position between the document sheet and the focal position is not considered. Although the relationship can be stabilized to some extent, it is not possible to prevent the reading glass from being stained by the unfixed material or to stabilize the feed speed of the document sheet at the focal position.

When the latter paper feed roll is used in a CVT type document reading device, show-through is prevented,
Although it is possible to stabilize the mutual positional relationship between the manuscript paper and the focal position to some extent or to stabilize the feeding speed of the manuscript paper at the focal position, dirt on the reading glass due to unfixed material cannot be suppressed. . In particular, when the paper feed roll is pressed against the reading surface, the mutual positional relationship between the original paper and the focal position can be highly stabilized, but dirt attached to the surface of the roll is pressed against the reading surface. There is a problem that image quality is significantly degraded due to contamination of the reading glass because it adheres.

[0012]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to develop a CVT type document reading apparatus capable of suppressing the contamination of a reading glass by unfixed material and reading a document image with stable image quality. .

[0013]

That is, according to the present invention, there is provided a document table on which document sheets are placed, a document discharge table from which document sheets are discharged, and one sheet of document paper from the document table to the document discharge table. A document sheet transporting means for transporting the document one by one, disposed along the document transport path, a transparent or translucent reading reference member, and disposed on a side of the reading reference member opposite to the document transport path; Reading means for irradiating the original paper with reading light via a reading reference member and reading an image of the original paper based on the reflected light from the original paper, and reading the original image while transporting the original paper In the reading apparatus, there is provided a document reading apparatus provided with a contact preventing means for preventing a document sheet from contacting a portion of a reading reference member through which the reading light or the reflected light passes.

In the present invention, the document table may be any table on which document sheets can be placed. For example, there is a document sheet tray.

The above-mentioned original discharge tray may be any as long as the original paper can be placed thereon. For example, there is an original discharge tray.

The manuscript paper conveying means may be any as long as it can convey manuscript paper one by one from the manuscript mounting table to the manuscript discharge table. For example, a plurality of manuscript papers arranged from the manuscript mounting table to the manuscript discharge table It can be constituted by a transport roll. The document transport path refers to a document paper transport path set between the document placing table and the document discharge table by the document paper transport unit.

The reading reference member may be disposed along the document transport path and may be formed of a transparent or translucent material. For example, a reading glass formed in a long flat plate shape may be used. is there.

The reading means is provided on the opposite side of the reading reference member from the document transport path, irradiates reading light to the document sheet via the reading reference member, and reflects light reflected by the document sheet. Any device that can read the image of the original paper based on the original can be used. For example, it can be configured with an illumination lamp and a CCD sensor arranged side by side on the opposite side of the original reference path from the reading reference member.

The contact prevention means only needs to function so as to prevent the original sheet from coming into contact with the portion of the reading reference member through which the reading light or the reflected light is transmitted. A sheet suction member disposed on the opposite side of the member and for sucking the document sheet by electrostatic suction force or negative pressure of air, or between the reading reference member and the document conveyance path, A step forming member is provided other than between the portion of the reading reference member through which the light or the reflected light passes and the document transport path, and forms a step between the side of the reading reference member on the document transport path side. be able to.

The step forming member may be any member that can form a step between the reading reference member and the side surface on the document conveying path side. For example, a plate having a predetermined thickness is disposed on the reading reference member. Just set it. In addition, even if the plate member is formed on the reading reference member by being formed separately from the reading reference member and attached to the reading reference member, it is formed integrally with the reading reference member. It may be arranged on the reading reference member. Note that the size of the step and the distance between the step and the reading surface may be set so that the least rigid document sheet does not contact the reading surface.

It is preferable that the step has an interval of 2 mm or more and 5 mm or less from the focal position of the reading means, and the size of the step is 0.3 mm or more and 0.7 mm or less. This not only prevents the original paper from adhering to the reading surface, but also allows the original paper to be stably passed through the focal position of the reading means, and reduces the feed speed of the original paper at the focal position. It can be stabilized, and the irradiation light of the illumination lamp is not blocked by the step forming member.

Further, it is preferable that the step forming member is provided on the upstream side rather than on the downstream side of the reading surface in the conveying direction of the document sheet. This is because, when a step is formed on the downstream side in the conveying direction of the original sheet, it is necessary to form a slope between the step forming member and the reading surface so that the sheet is not caught by the step, and the step forming member This is because the reading surface and the reading surface must be separated from each other, so that the above-mentioned step must be made large.

Further, it is preferable that the side surface of the step forming member on the document conveying path side is formed of a material having a low friction coefficient.
For example, there are glass, high molecular weight polyethylene, fluororesin, polyacetal (POM), nylon and the like. Thus, it is possible to prevent the original sheet from being twisted due to friction between the original sheet and the step forming member.

In the document reading apparatus of the present invention, a contact preventing means is provided so that the document sheet does not come into contact with the portion of the reading reference member through which the reading light or the reflected light is transmitted. Even if the original image of the original sheet is read, the unfixed image does not adhere to the portion of the reference member.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Incidentally, the present invention is applicable to an original reading apparatus in which a background portion forming member is arranged so as to face the above-mentioned reading reference member, or a paper feeding means is arranged so as to face the above-mentioned reading reference member. Or a document reading device.

The background portion forming member may be any member as long as it can be arranged to face the reading reference member and reflect irradiation light transmitted through the manuscript paper. For example, the background portion forming member is arranged to face the reading surface. There is a flat plate shaped.

The paper feeding means may be any one provided so as to be opposed to the reading reference member and capable of stabilizing the feeding speed of the original paper at the focal position. For example, the paper feeding means disposed in pressure contact with the reading reference member There is a role. Since the original sheet has a predetermined thickness, the sheet can be conveyed if the sheet feed roll is opposed to the reading reference member at an interval smaller than the thickness.
Specifically, if the thickness is 0 to 0.3 mm, the sheet can be transported. The sheet feeding means may be arranged so as to be in pressure contact with the reading surface so as to also serve as the background portion forming member.

When these techniques are combined with the present invention, the paper feeding means presses against the step forming member rather than presses the reading reference member,
The side surface of the step forming member on the document conveying path side may be formed of a material having a lower coefficient of friction than the sheet feeding means. For example, glass, high molecular weight polyethylene, fluororesin, P
OM, nylon and the like. Thus, it is possible to prevent the feeding of the original sheet from becoming unstable due to the friction between the original sheet and the step forming member. In particular, when the surface of the step forming member is formed of a material having a lower coefficient of friction than glass conventionally used as a reading reference member, for example, high-molecular-weight polyethylene, compared with a case where the document feeding means is pressed against the reading reference member. The manuscript paper can be stably conveyed.

Further, when these techniques are combined with the present invention, the paper feeding means is disposed in pressure contact with the reading surface, so that the paper feeding means does not have the function of the background portion forming member. It is preferable to dispose both the means and the background portion forming member adjacent to each other. This not only prevents the paper feeding means from adhering dirt to the reading surface, but also allows the paper feeding means to be set smaller when the paper feeding means is formed by a paper feeding roll. Since the conveying force is applied, the distance between the background portion forming member and the reading reference member can be reduced so that the original sheet does not deviate from the focal position (that is, the image quality of the read image (distortion or image bending). ) Is improved). In addition, conventionally,
In consideration of the image quality of the read image, it is preferable that the interval between the reading reference member and the background portion forming member be a narrow interval (0.5 to 1.0 mm) so that the sheet does not shift from the focal position. In such a case, the feeding speed of the original sheet becomes unstable due to friction between the original sheet and these members, and therefore, in practice, a wide interval (1.0 to 1.0) which does not hinder the feeding of the original sheet. 1.5 mm).

Further, when the sheet feeding means and the background portion forming member are used in combination, there is no possibility that the sheet feeding means faces the reading surface and affects the image quality. A member can be used.

Also, the present invention relates to a so-called CVT type document reading apparatus, wherein a platen glass on which a document sheet is placed, a platen cover rotatably fixed above the platen glass, and a platen cover, A so-called platen having an illumination lamp movably disposed below the glass, a CCD sensor in which a large number of photoelectric conversion elements are arranged, and an optical element such as a mirror for inputting reflected light from a document to the CCD sensor. One document reading device can be formed in combination with a document reading device of the system.

In combining these techniques, it is preferable to use the above-mentioned document placing table, document discharging table and document sheet conveying means as a part of an automatic document feeder for supplying document sheets to the platen glass. In this case, the document mounting table, the document discharge table, and the document sheet conveying means may be formed integrally with the platen cover and arranged to be openable and closable with respect to the reading reference member. Hereinafter, the member on which the platen glass and the document placing table are provided is referred to as a reading device main body. The reading device main body is provided so as to be openable and closable with respect to the reading device main body, and the platen cover and the document paper conveying means are provided. The member that is located is called a cover body. Further, in this case, the background portion forming member and the sheet feeding means may be provided on the reading device main body side, or may be provided on the cover main body side.

When the background forming member and the sheet feeding means are provided on the cover body side, a supporting member is provided so as to be swingable with respect to the cover body, and the supporting member is provided with the supporting member. It is preferable that a background portion forming member and a sheet feeding means are provided so that the support member swings when the cover body is closed. Accordingly, even if the positioning accuracy of the cover main body with respect to the reading device main body is not sufficient, the sheet feeding means and the background portion forming member are brought into contact with the reading reference member (reading member) by contacting the sheet feeding means with the reading reference member or the step forming member. Surface) can be easily positioned.

Further, in the above configuration, as a method for improving the accuracy of the interval between the background portion forming member and the reading reference member, for example, a paper feed roll is used as the paper feed means, and the paper feed roll is opened and closed about the rotation axis of the roll. A background portion forming member is disposed as possible, a spacer having a height corresponding to a distance from the reading reference member is disposed on the background portion forming member, and the background portion forming member is pressed against the reading reference member side. What is necessary is just to provide the press-contact force giving member which performs. This allows the paper feed roll to abut on the reading reference member or the step forming member over the entire width thereof, thereby making the distance constant in the rotation axis direction of the roll, and the spacer is moved to the reading reference member. Alternatively, by making contact with the step forming member, the above-described interval can be set to a desired value in the sheet conveyance direction, so that the accuracy of the interval can be improved.

Hereinafter, some specific examples of the combination of the present invention will be described with reference to the accompanying drawings.

(Configuration Example 1) The document reading apparatus shown in FIG.
A step forming member 2a is arranged on the reading glass 1, and
In this configuration, a flat plate 3 is disposed so as to face and separate from the reading glass 1 and the step forming member 2a. Note that P in the drawing indicates an original sheet, and R indicates the direction of reflection of reflected light by the original sheet (the same applies to the following configuration examples).

(Configuration Example 2) The document reading apparatus shown in FIG.
A step forming member 2a is arranged on the reading glass 1, and
The configuration is such that a background portion roll 3b is disposed so as to face and be separated from the reading glass 1.

(Configuration Example 3) The document reading apparatus shown in FIG.
This is a configuration example in which a plate-shaped plate 3 is provided so as to face and separate from the reading glass 1 and a sheet suction member 2b is provided at a position facing the reading surface.

(Configuration Example 4) The document reading apparatus shown in FIG.
A step forming member 2a is disposed on the reading glass 1, and a flat plate 3 is provided so as to face the reading glass 1 and to be separated therefrom.
Is provided, and a paper feed roll 4a is further placed in pressure contact with the step forming member 2a.

(Configuration Example 5) The document reading apparatus shown in FIG.
A step forming member 2a is disposed on the reading glass 1, and a flat plate 3 is provided so as to face the reading glass 1 and to be separated therefrom.
This is a configuration example in which a vibration transport member 4b is disposed in pressure contact with the step forming member 2a.

(Configuration Example 6) The document reading apparatus shown in FIG.
A flat plate 3 is provided so as to be opposed to and separated from the reading glass 1, and a sheet suction member 2b is provided at a position facing the reading surface. This is an example of a configuration in which a paper feed roll 4a is disposed in pressure contact with a sheet. In the following configuration example, the plate 3
And a configuration example in which the paper feeding means 4 is provided on the cover body.

(Configuration Example 7) The document reading apparatus shown in FIG.
Support arm 5 swingably disposed with respect to the cover body
The plate 3 and the paper feed roll 4a are disposed so as to be openable and closable, the spacer is disposed on the plate 3, and the elastic force applying member 7 that presses the plate 3 against the reading glass 1 is disposed. It is an example.

(Configuration Example 8) The document reading apparatus shown in FIG.
Support arm 5 swingably disposed with respect to the cover body
This is an example of a configuration in which the plate 3 is disposed so as to be freely opened and closed, and a spacer and a vibration transport member 4b are disposed on the plate 3.

(Configuration Example 9) The document reading apparatus shown in FIG.
Paper suction member 2 together with plate 3 and paper feed roll 4
This is a configuration example in which b is disposed on the cover body.

[0045]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

Embodiment 1 FIG. 10 shows a digital copying machine to which the present invention is applied. The digital copier includes a document reading unit on which a document sheet Ps is placed, and reads an image of the document sheet Ps as image information by a platen method or a CVT method, an image storage unit that stores the image information, and an image storage unit. And an image forming unit that forms an image on the recording paper Po based on the image information stored in the unit.

The original reading section is provided in the main body of the copying machine, and is a reading system for optically reading an image of the original paper Ps;
It comprises automatic document feeding means which can be opened and closed with respect to the upper surface of the copying machine main body.

The reading system means includes: a platen glass 16 provided on the upper surface of the copying machine main body;
6, a reading glass 1 arranged side by side at one end, a first carriage 17 disposed below the reading glass 1 as a home position and movably disposed to the other end of the platen glass 16, It has a second carriage 18 that moves in conjunction with the carriage 17, and a CCD sensor 19 disposed below the home position of the first carriage 17. The first carriage 17 includes an illumination member 17a that includes an illumination lamp and a reflection plate, and irradiates the original sheet Ps with irradiation light, and a first mirror 17b that reflects the illumination light reflected by the original sheet Ps. The second carriage 18 is provided with a second mirror and a third mirror for making the light reflected by the first mirror 17b incident on the CCD sensor 19. In the following description, the light emitted from the illumination member 17a at the home position, reflected by the original paper Ps, and reflected by each of the mirrors and incident on the CCD sensor 19 intersects the entire area where the light intersects the upper surface of the reading glass 1. Is referred to as a reading surface S. A position in the reading surface S corresponding to the focal point of the CCD sensor 19 is referred to as a center of the reading surface S (a position where the dashed line in FIG. 12 intersects with the reading glass 1).

The automatic document feeder is provided at a position opposite to the platen glass 16 of the feeder frame 8 provided in the copier main body so as to be openable and closable, and has a white surface. And a platen glass cover 15 provided on the upper surface side of the feeding means frame 8 and on which a plurality of document sheets Ps can be placed.
And a document sheet feeding member that feeds the document sheets Ps one by one from the document placing tray 14, passes over the reading glass 1, and then discharges the document sheet onto the upper surface of the feeding unit frame 8. In FIG. 10, reference numeral 11 denotes a pickup roll for pulling in the original paper Ps from the original mounting tray 14, 12 a registration roll for feeding the original paper Ps to the reading glass 1, and 13 a discharge for discharging the original paper Ps onto the feeding means frame 8. The roll 10 is an upstream chute, and 9 is a downstream chute. These are all the above-mentioned document sheet feeding members and are arranged on the above-mentioned feeding means frame 8.

When the original paper Ps is placed on the platen glass 16, the digital copying machine
While reading the image of the original sheet Ps and forming an image corresponding to the original image on the recording sheet Po, when the original sheet Ps is placed on the original placing tray 14, the original sheet Ps The image is read and an image corresponding to the document image is formed on the recording paper Po. Hereinafter, the former is referred to as a platen mode, and the latter is referred to as a CVT mode. In the platen mode, the platen glass 1
In order to place the original paper Ps on the sheet 6, as shown in FIG. 11, open the automatic original feeder, place the original paper Ps on the platen glass 16, and then close the automatic original feeder. Good.

In the platen mode, the original reading section illuminates the original paper Ps on the platen glass 16 by operating the illumination lamp and the CCD sensor 19 and then moving the two carriages 17 and 18. While scanning with the member 17a, the reflected light from the original paper Ps is input to the CCD sensor 19, and the image on the original paper Ps is read.

On the other hand, in the CVT mode, the original reading section operates the illumination lamp and the CCD sensor 19 and then operates the original sheet feeding member, thereby passing the original sheet Ps over the reading glass 1. At the same time, the image on the original paper Ps is read through the reading glass 1.

The image forming section includes a recording sheet storage tray 29 for storing a large number of recording sheets Po, and a toner image transfer member for forming a toner image corresponding to the image information stored in the image storage section on the recording sheet Po. And the toner image on a recording paper Po
, A recording paper discharge tray 28 for storing the recording paper Po on which an image is formed, and a recording paper discharge tray from the recording paper storage tray 29 via a toner image transfer member and a toner image fixing member. And a recording paper Po feeding member for conveying the recording paper Po up to 28.

The toner image transfer member is a photoconductive drum 2 which is openably and closably disposed facing the recording paper transport path.
The photosensitive drum 23 is charged to a uniform potential by a uniformly charged corotron 22, and the photosensitive drum 23 is exposed by a laser exposure unit 21 to form an electrostatic latent image.
The electrostatic latent image is developed to form a toner image, and the toner image is transferred to the recording paper Po by a transfer corotron arranged opposite to the photosensitive drum 23 via the recording paper transport path. Then, a toner image corresponding to the image information stored in the image storage unit is formed on the recording paper Po.

The image forming section forms a toner image on the photosensitive drum 23 in accordance with the image information, and transfers and fixes the toner image on the recording paper Po. By discharging the recording paper Po, an image is formed on the recording paper Po.

In this embodiment, a high-molecular polyethylene tape as the step forming member 2a is attached to the reading glass 1 on the upstream side of the reading surface S, while the reading glass 1 faces the reading surface S of the reading glass 1. The flat plate-shaped white plate 3 was disposed so as to be spaced apart therefrom, and a paper feed roll 4a made of silicon was pressed against the step forming member 2a.

In this embodiment, the feeding means frame 8
The plate 3 and the paper feed roll 4a are rotatably disposed on the support arm 5 so that the plate 3 and the paper feed roll 4a are rotatable. Has been established.

Further, in the present embodiment, the support arm 5 is pressed so that the paper feed roll 4a is pressed against the step forming member 2a.
A first spring 6 for applying an elastic force to the plate 3, a second spring 7 for applying an elastic force to the plate 3 so as to press the free end side of the plate 3 against the reading glass 1, and reading the plate 3 By arranging the spacer 3a on the side surface opposite to the glass 1, the plate 3 and the plate 3 can be positioned with respect to the reading glass 1 and the step forming member 2a regardless of the positioning accuracy of the automatic document feeder with respect to the copying machine body. The paper feed roll 4a can be positioned with high accuracy.

In this embodiment, the distance between the center of the reading surface S and the step forming member 2a is set to 5 mm, and the size of the step is set to 0.3 mm. In the present embodiment, the minimum distance between the plate 3 and the reading glass 1 is set to 0.5 mm. Further, the paper feed roll 4a was set so as to be pressed against the step forming member 2a at a position 8 mm from the center of the reading surface S. Incidentally, the distance between the center of the reading surface S and the end of the reading surface S on the upstream side in the sheet transport direction is 5 mm. If the distance is set to 2 mm or less, the amount of light incident on the CCD sensor 19 is reduced. Will decrease.

In the present embodiment, the original paper Ps to which the correction liquid which has not been dried is applied is read by the digital copying machine. As a result, in the above digital copying machine,
A large amount of the correction liquid adhered to the step forming member 2a, but did not adhere to the reading surface S at all. After the completion of the reading, when the ordinary document paper Ps was read by the digital copying machine, no image quality defect due to white streaks or black streaks occurred.

By the way, in the above digital copying machine,
The degree of adhesion between the reading glass 1 and the original paper Ps was measured by changing the step size to 0.3 mm and 0.5 mm.
In both cases, the original paper Ps hangs down by 0.2 mm at a position 5 mm downstream of the step regardless of the size of the step. In addition, when the dirt on the reading glass 1 was examined in the digital copying machine, no dirt was found at least 7 mm downstream from the step.
Further, in the above digital copying machine, 5 m downstream of the step
m, the center of the reading surface S was set to be located at the position m, and the deviation of the magnification of the read image was examined.
Even when the distance is m, the deviation of the magnification of the read image was at a level without any problem.

As described above, in the digital copying machine of the present embodiment, the center of the reading surface S, that is, the distance between the focal position of the reading means and the step is 2 mm or more and 5 mm or less, and the size of the step Is 0.3 mm or more and 1.3 mm or less, not only can the reading surface S be prevented from being stained, but also
The original sheet Ps can be set so that the original sheet Ps can pass stably through the focal position of the reading unit.
Of the lighting member 1 can be stabilized.
The irradiation light 7a is not blocked by the step forming member 2a.

COMPARATIVE EXAMPLE 1 The digital copying machine of this comparative example is a digital copying machine to which the above-described embodiment is applied, in which a paper feed roll 4a made of silicon is pressed against the reading glass 1 upstream of the reading surface S thereof. It is. The paper feed roll 4a is mounted via a support arm 5 that is swingably disposed on the feed means frame 8, and the support arm 5 presses the paper feed roll 4a against the reading glass 1. Elastic force.
The position where the paper feed roll 4a of the reading glass 1 is pressed is referred to as a pressed position. Further, in the present comparative example, the distance between the pressed position and the center of the reading surface S was set to 8 mm.

Then, in this comparative example, the original paper Ps to which the correction liquid that has not been dried was applied was read by the digital copying machine. As a result, in the above digital copying machine,
A large amount of the correction liquid has adhered to the reading glass 1.
In addition, the range extends from the upstream side to the downstream side of the press-contact position, and particularly the downstream side of the press-contact position, the correction fluid adhered even at a position 10 mm or more from the press-contact position. . After the completion of the reading, when the normal document paper Ps was read by the digital copying machine, image defects due to white streaks and black streaks occurred in the entire image.

[0065]

As described above, in the original reading apparatus of the present invention, a contact preventing means for preventing the original sheet from contacting the portion of the reading reference member through which the reading light or the reflected light is transmitted is provided, and the unfixed material of the original sheet is provided. Is prevented from adhering to the portion of the reading reference member, so that the reading glass can be prevented from being stained by the unfixed material, and the original image can be read with stable image quality.

[Brief description of the drawings]

FIG. 1 is a configuration example (part 1) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 2 is a configuration example (part 2) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 3 is a configuration example (part 3) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 4 is a configuration example (part 4) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 5 is a configuration example (part 5) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 6 is a configuration example (part 6) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 7 is a configuration example (part 7) of a main part of a document reading apparatus to which the present invention is applied.

FIG. 8 shows an example (part 8) of a main part configuration of a document reading apparatus to which the present invention is applied.

FIG. 9 is an example (part 9) of a main part configuration of a document reading apparatus to which the present invention is applied.

FIG. 10 is a schematic configuration diagram of a digital copying machine according to the first embodiment of the present invention.

FIG. 11 is an explanatory diagram of a procedure for placing an original sheet on a platen glass in the digital copying machine in FIG. 10;

FIG. 12 is a configuration diagram around a reading glass of the digital copying machine of FIG. 10;

[Explanation of symbols]

Reference numeral 14: Document mounting table, 8: Document discharge table, 9 to 13: Document paper transport means, 1: Reading reference member, 17 to 19: Reading means, Ps: Document paper, 2a: Step forming member (contact prevention means) , 4a: paper feeding means, 3: background portion forming member, 8:
Frame, 5: support member, 3a: spacer, 7: pressing force applying member.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/00-1/00 108 H04N 1/04-1/207

Claims (2)

(57) [Claims] An original placing table on which the original is placed;
The document output tray to be ejected, and the document
Document transport means for transporting documents one by one by
Along the document transport path from the table to the document discharge table,
Transparent or translucent reading reference member and this reading base
For documents that pass through the document reading surface
And irradiates the reading light, and based on the reflected light,
A document reading device provided with a reading means, wherein a frame which can be opened and closed with respect to the reading reference member is provided;
On the other hand, on the reading reference member and upstream of the document reading surface, a predetermined
Reading the original by providing a step forming member having a thickness of
To prevent the original from contacting the document surface, and furthermore, a position facing the reading reference member with the original conveyance path interposed therebetween.
Is provided with a paper feeding means for applying a conveying force to the original.
On the downstream side of the sheet feeding means, the reading reference member is provided.
A background portion forming member is provided at an interval, and the paper feeding means and the background portion forming member are connected to the frame.
The frame is supported via a support member that is swingably disposed with respect to the frame.
Document reading device, which is attached to the
Place. 2. The image forming apparatus according to claim 1, wherein the background forming member includes the reading reference member.
And a spacer protruding toward
A pressing force applying member for pressing the sensor against the reading reference member is provided.
2. The document reading device according to claim 1, wherein: