JP2000216952A - Image scanning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent nonconformities due to intervening of an original or the mixing of foreign matters and the like, when any partial floating or clearance due to the deformation or distortion of a standard plate is generated between an original placing table and a standard plate being the standard position of an original to be placed. SOLUTION: A transparent original placing table 22 for optically reading an image is positioned at a recessed part 35 of a supporting frame 34, and a standard plate 30 for deciding the placing position of an original is mounted to be fixed via a pedestal 37 on the mounting face of the supporting frame 34 with a bis 33. The standard plate 30 is integrated with a cabinet 36 which is one part of an armor constituting an image reading device, so that any distortion or deformation or the like can be prevented from being generated at the molding of the standard plate 30. Therefore, any partial floating or clearance due to the deformation or distortion of the standard plate 30 can be prevented from being generated between the standard plate 30 and the original placing table 22 at the time of mounting the standard plate 30 on the supporting frame.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image scanning apparatus which optically forms an image on a transparent mounting table, that is, an original on a document table (transparent platen) at a desired position.

[0002]

2. Description of the Related Art In an image forming apparatus, image data of a document, image data input from another apparatus, and the like are visualized so as to be viewed, and are output as a hard copy. This image forming apparatus, for example, in the case of an analog copying machine, is provided with an image scanning apparatus having a photoconductive layer as an image carrier and a scanning optical system for forming an image on a uniformly charged photoconductor. ing.

Further, according to the digital copying machine, an original placed on an original platen surface mainly formed of a transparent member such as glass is optically scanned with light emitted from a light source.
A scanning optical system for forming an image of the obtained reflected light on a light receiving portion of a photoelectric conversion element (reading element) such as a CCD as a reading element and reading the image is provided.

The above-described image scanning apparatus is generally called a scanner, and moves an original and a part of an optical system relatively to form an image at a desired position line by line. ing. For this reason, the image is sequentially formed on a desired position, for example, a photoconductor or a reading element (CCD) by moving and scanning the optical system while the document is stationary on the document table. Also, by moving the original on the platen at a predetermined speed while the optical system is stationary, that is, by conveying the original,
Images are sequentially formed at the desired positions described above. In this method, an image is sequentially scanned by moving a document and an optical system relatively, and there is a method in which an image of a stationary document is exposed to a desired position at a time, that is, an image is formed.

[0005] As described above, an image of a document is formed by the image scanning device, so that an electrostatic latent image corresponding to the image is formed on the photosensitive member, and the electrostatic latent image is transferred to the developing device. Then, the image is visualized, transferred to a sheet or the like, and discharged to obtain a hard copy.

Such an image forming apparatus is not limited to an analog or digital copying machine of the electrophotographic system as described above, but can be used to visually check image data created by an information processing apparatus such as a personal computer or a word processor. There are printers that reproduce as much as possible and output this as a hard copy, such as a laser printer, an inkjet printer, and a thermal printer.

[0007] As described above, the image forming apparatus is configured to provide a reproduced image desired by the user.
On the other hand, as a device for inputting image data to an image forming apparatus or the like, a document is placed on a placing table formed of transparent glass or the like as described above, that is, a document table. The provided image of the document is provided via the image scanning device. In this case, image processing or the like is performed so that the image can be reproduced by the image forming apparatus, and the image is projected on the photoconductor.

The above-described image scanning apparatus is permanently installed in a digital copying machine, a facsimile, or the like, and is connected to a personal computer or the like via a line for communicating data and the like as a scanner to read a desired image. , Image editing processing.

Therefore, the conventional scanner, that is, the image scanning device, will be briefly described with reference to FIG.
A scanning optical system 23 is provided for forming an image of a document placed on the transparent document table 22 at a desired position and finally reading the image. The scanning optical system 23 is
Exposure lamp 24 for illuminating light 2, reflected light from the document, that is, image light, is appropriately reflected and is a target position (desired position) C
A reflection mirror 25 for guiding to a reading element 29 such as a CD,
26, 27 and the light receiving surface (reading surface) of the reading element 29
And an image forming lens 28 for forming an image of the reflected light.

The exposure lamp 24 and the reflection mirror 25 are supported by the same first support, and the reflection mirrors 26 and 27 are supported by another second support. The first and second supports are moved along the document table 22. At the same time as the traveling speed V2 of the second support is set to 1/2 of the second traveling speed V1, the images of the originals on the original platen 22 are sequentially formed. Reading is performed for each scanning line.

The scanning optical system 23 conveys the document at a predetermined speed onto the document table 22 in a state where the scanning optical system 23 is stopped at the position shown in the drawing, so that the image of the document is sequentially placed on the light receiving surface of the reading element 29. It will also be imaged.

The document table 22 is provided with a reference plate for placing the document at a predetermined position, in particular, for placing the document with its leading edge regulated. For example, as shown in FIG. 8, a reference plate 60 is provided so as to cover one end of the transparent document table 22, and the document is placed on the reference plate 60 so that one edge of the document is aligned. The reference plate 60 is partially provided with a mark indicating the size of the document, and the document is placed with one edge (one side) of the document along the reference plate 60.

Here, in the conventional mounting structure of the document table 22, as shown in FIG. 8, the document table 22 is supported on a supporting frame 61, and a reference plate 60 is attached to the supporting frame 61. The document table 22 is supported and fixed so as to be sandwiched therebetween. In the figure, a support frame 61 has a concave portion 62 for supporting the document table 22,
The reference plate 60 has a step (support surface) 63 that supports a part of the reference plate 60, and the reference plate 60 is fixed to the step 63 with a screw 65 or the like via a pedestal 64. It is supported by being sandwiched between the concave portions 62.

The document table 22 is attached in this manner,
An image of the original on the original platen 22 is optically scanned by a scanning optical system 23 located below the original platen 22 to form an image at a desired position.

[0015]

However, according to the platen mounting structure having the structure shown in FIG. 8, since the reference plate is mounted so as to cover the platen from above the platen, the reference plate 60 and the platen 22 are attached. When the document is removed from the document table after scanning the image, a part of the document is torn or the document cannot be removed.

That is, when the reference plate 60 is formed of a resin as shown in FIG. 8, since the reference plate 60 is formed in a substantially flat plate shape, it is deformed by twisting or distortion at the time of molding and is attached as it is. Between the reference plate 60 and the platen 22,
Large gaps or floating due to torsion or deformation may occur partially. Then, plastic deformation is apt to occur due to the heat of the exposure lamp and the like, and the above-mentioned gaps and the like become remarkable. Therefore, the document is interposed in the gap, and the above-described problem occurs. Further, not only the original document but also dust may enter and affect the optical scanning of the scanning optical system, or rubber may enter the reading optical path, thereby causing a reading error such as distortion of the read image.

Reference numeral 66 denotes an exterior of the image reading apparatus, which is formed separately from the normal reference plate 30,
1 is fixed from the side by screws 67 or the like.

As shown in FIG. 9, the document table 22 is placed in the concave portion 62 of the support frame 61, the reference plate 60 is covered from above, and screws are attached to the support surface 63 of the support frame 61 via the base 64. By fixing at 65, the reference plate 60 is attached by absorbing the deformation and torsion. However, a gap D is formed between the document table 22 and the reference plate 60. When a document is interposed in the gap D, the above-described problem occurs.

In FIG. 9, the above-mentioned gap D occurs due to the mounting error and the relation of the pedestal 64 in FIG. In other words, since the support surface 63 of the support frame 61 of the pedestal 64 is parallel, that is, normally in a horizontal state, the error and the reference
It is not possible to eliminate the gap D or the like by absorbing zero deformation or the like. Also, a gap D is formed entirely due to an error of the pedestal 64, and conversely, the reference plate 60 is strongly pressed only at both ends of the document table 22, the central portion is largely bent upward, and a large gap D is formed. Is done.

Further, as described above, when the reference plate 60 is formed by resin molding, the above-mentioned gap D becomes more conspicuous due to twisting or warping. Therefore, as described above, it is not possible to solve the problem of the document being interposed or the problem of the dust being mixed.

An object of the present invention is to provide an image scanning apparatus in which the above-mentioned problem, that is, the floating between the document table and the reference plate, particularly, the gap is reduced as much as possible, and the reference plate is attached so that the document is not interposed. With the goal.

It is another object of the present invention to provide an image scanning apparatus which prevents twisting and distortion when molding a reference plate, thereby preventing the above-mentioned floating between the platen. .

[0023]

According to a first aspect of the present invention, there is provided an image scanning apparatus for optically scanning a document on a document table and forming an image on a desired position. In an image scanning device including an optical system for imaging,
A reference plate indicating a reference position of the document is mounted on the platen so as to cover the platen from above, and the reference plate is integrated with a cabinet forming a part of the exterior of the image scanning apparatus. And

According to such a configuration, since the reference plate is integrated with the cabinet which is a part of the exterior of the image scanning apparatus, when the reference plate is molded with resin, it is formed by integral molding or the like. The strength of the reference plate itself is increased. That is, the occurrence of twisting, deformation, and the like during formation is reduced, and thus, floating and gaps with the platen are suppressed. Furthermore, plastic deformation due to radiant heat or the like when scanning the document is reduced. Further, in the assembling work, the mounting accuracy is increased because no deformation or the like occurs, and the work of separately mounting a cabinet as in the conventional case shown in FIG. Goes up.

Next, in the image scanning apparatus having the above-described configuration and features, according to the second aspect of the present invention, the cabinet is a vertical exterior in a direction orthogonal to a plane portion of the reference plate. And That is, since the cabinet integrated with the reference plate has a vertical exterior orthogonal to the reference plate, reinforcement of the reference plate provided in a horizontal state in integral molding is further improved. That is, in the case of resin molding, since the cabinet acts as a reinforcing material, the cabinet can be accurately formed in a horizontal state on the surface of the document table without twisting or deformation. As a result, the effect of preventing the occurrence of a gap, floating, or the like between the document table and the document table increases.

According to a third aspect of the present invention, there is provided an image scanning apparatus for optically scanning a document on a document table and forming an image on a desired position. When the reference plate indicating the reference position of the document on the platen is fixed to the mounting surface of the support frame from above the supported platen, the reference plate is placed on the platen side. A mounting member is provided for fixing the mounting member so as to bend and bend, and the mounting member and the mounting surface are aligned in an inclined state.

That is, as shown in FIG. 2, the mounting surface 34 of the support frame 34 is
The reference plate 30 is mounted on a with screws 33 or the like. At the time of this mounting, a mounting member 37 is provided between the reference plate 30 and the support frame 34, and the surfaces of the mounting member 37 facing the mounting surface 34a of the support frame 34 are mounted so as to be inclined to each other. Therefore, the reference plate 30 is bent so as to bend toward the document table 22, and the reference plate 30 can be attached without forming a gap or the like with the document table 22. For this reason, distortion and twist during molding of the reference plate 30,
Even if some deformation or the like occurs, the reference plate is attached to the platen so as to absorb the deformation, and it is possible to prevent a gap or floating. Thus, the design accuracy of the reference plate 30 is not required, and the manufacturing cost and the like can be significantly reduced.

Moreover, there is no plastic deformation due to radiation heat of an exposure lamp or the like during scanning. In other words, since the reference plate bends in a curved manner and is urged so as to be pressed against the document table, the reference plate is satisfactorily urged without being deformed by radiant heat or the like, and the deformation is absorbed.

In the image scanning apparatus having the above-mentioned structure, according to the fourth aspect of the present invention, the mounting member is a mounting pedestal provided integrally with the reference plate, and is supported by the pedestal. It is characterized in that an inclined surface inclined with respect to the mounting surface of the frame is provided. With such a configuration, the pedestal serving as a mounting member can be integrally provided on the reference plate to increase the positional accuracy of the pedestal for mounting, and at the same time, the reference surface can be provided by providing an inclined surface on the pedestal. It is possible to increase the mounting accuracy of the plate, and furthermore, to satisfactorily bend the reference plate toward the platen as described above.

[0030] In the image scanning apparatus having the above-described configuration, according to the invention described in claim 5, the reference plate forms a part of an exterior of the image scanning device, and the flat portion of the reference plate is formed. Characterized in that it is a vertical exterior in a direction orthogonal to the above. In this way, by integrating the reference plate with the cabinet that forms a part of the exterior of the image scanning device, twisting and deformation during molding of the reference plate are minimized, and at the same time, when the reference plate is attached, This can promote the effect of eliminating partial floating and gaps generated between the table and the table.

According to a sixth aspect of the present invention, in the image scanning apparatus having the above-described configuration, the inclined surface formed on the pedestal of the mounting member is configured such that the inclination angle of the reference plate is set to a value closer to the original table side. 10g of pressure when bending and contacting
/ Cm to 50 g / cm.
With such a pressure setting, the effect that the document intervenes between the platen and the reference plate increases. In addition, it is possible to prevent the document table and the like from expanding due to radiant heat at the time of scanning, thereby preventing damage to the document table and damage or deformation of the reference plate itself.

In the above-described image scanning apparatus according to the first or third aspect, according to the seventh aspect of the invention, the image scanning apparatus sequentially forms an image at a desired position while transporting the original. The reference plate is a pick-up member having a function of peeling the document after image formation from the platen, and the reference plate is provided with an inclined portion at an edge thereof. That is, when scanning an image while transporting a document, the reference plate functions as a scooping member. In this case, since the scooping member is peeled off from the platen after the document is scanned, the generation of a gap or floating between the platen and the platen may hinder conveyance or damage the document. However, since the scooping member can be provided so as to be in good contact with the document table, the effect can be particularly exhibited when the document is scanned while being conveyed. Moreover, by forming an inclined surface on the edge of the scooping member, the scooping effect of the document is increased, and the effect of eliminating the conveyance failure of the document is promoted.

[0033]

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a side view showing an attached state of a document table and a reference plate in the image scanning apparatus according to the present invention, and FIG. 2 is a view for explaining the attached state, as viewed from the right side in FIG. FIG. 3 is a perspective view showing an external appearance of the image scanning apparatus according to the present invention, showing a developed state of each unit, and FIG. 4 is a configuration diagram showing an internal structure of a digital copying machine provided with the image scanning apparatus according to the present invention. is there.

First, an image scanning apparatus according to the present invention provided in a digital copying machine as an image forming apparatus will be described with reference to FIG. FIG. 4 shows a digital copying machine provided with a scanner for reading an image as an image scanning device according to the present invention, but may be provided as a single scanner.
In a facsimile machine, a scanner is also permanently provided. Further, the personal computer is connected via a communication cable or the like, and the scanner reads an image of a document based on a read command, and sends the read image data to the personal computer.

Therefore, the main body of the digital copying machine 1 is provided with an image reading device 2 as an image scanning device according to the present invention on the upper portion, and reproduces image data read by the image reading device 2 on the lower portion as a hard copy. Image forming unit 3 for performing
It has.

In the image forming section 3, a plurality of process means for forming an image are arranged around a drum-shaped photosensitive member 4 which is an image carrier rotated in the direction of an arrow in the center. First, a charger 5 for uniformly charging the photoconductor 4, an exposure position 7 for irradiating a light image corresponding to image data from a laser irradiation device 6, and an electrostatic latent image formed according to the light image are visible. A developing device 8 for forming an image, a transfer device 9 for transferring a developed image (generally, a toner image) to a sheet P that is appropriately conveyed, a cleaning device 10 for removing toner remaining after the transfer and reusing the photoconductor, and the like Are provided in the order described.

A large number of the sheets P are accommodated in a sheet feeding cassette 12 constituting a lower sheet feeding means 11, fed one by one from the top, and a registration roller disposed in front of the transfer unit 9. 13 is sent. The sheet P is temporarily stopped by the registration roller 13, and is transferred to the transfer device 9 and the photoconductor 4 by the registration roller 13 in accordance with the rotation of the photoconductor 4.
Is controlled to a transfer position opposite to the transfer position. The sheet P sent to the transfer position is transferred to the photosensitive member 4 by the action of the transfer device 9.
Is transferred from the photoconductor 4, and is sent to a fixing device 14 for heating and fixing the transferred toner image.

The fixing device 14 includes a heat roller and a pressure roller. When the sheet P is nipped and conveyed, the toner is melted by the heat of the heat roller and fused to the sheet P by pressure to fix the sheet. Do. The sheet P passing through the fixing device 14 has a reproduced image corresponding to the image data formed on the surface thereof, and is subjected to a sheet discharging process via a sheet discharging roller 15 to a discharge unit 16 located outside the image forming apparatus.

The configuration of the image reading device 2 according to the present invention for transmitting image data to the laser irradiation device 6 of the image forming apparatus 1 will be described below.

The image reading device 2 is provided on the upper portion of the image forming device 1, and an openable / closable document cover 20 is provided on the uppermost portion. The document cover 20 is opened and closed corresponding to a document table 22 constituting a document mounting portion made of a transparent glass or the like on the upper part of the image reading device 2.
The image reading device 2 is pivotally supported on the upper main body side.

The document cover 20 is provided with a white pressing sheet on a surface facing the document table 22 on an exterior formed of resin or the like, and the pressing sheet is attached to a pressing member 21 made of, for example, a sponge member. It is pasted. Therefore, by closing the document cover 20, the document placed on the document table 22 can be pressed against the surface of the document table 22 by the action of the pressing member 21 and brought into close contact therewith.

The image reading device 2 below the document table 22
A scanning optical system 23 for reading an image of the placed document is provided in the main body. This scanning optical system 23
As is well known, an exposure lamp 24 for irradiating the original with light, and a CCD as reading means according to the present invention for reflecting light from the original
There are provided a plurality of reflection mirrors 25 to 27 for guiding the reflected light to an imaging lens 29, and an imaging lens 28 for imaging the reflected light on the light receiving surface of the CCD 29.

In particular, the scanning optical system 23 has scanning means for optically scanning the placed document, and this scanning means supports the exposure lamp 24 and the reflection mirror 25 on a first scanning member, One set of reflecting mirrors 2 is provided on the second scanning member which is driven and scanned at half the scanning speed of the first scanning member.
6, 27 are supported. Then, by moving these first and second scanning members to the right side in FIG. 4, for example, the reflected light from the original on the original table 22 is reflected by the reflection mirrors 25 to 27, and is reflected via the imaging lens 28. An image is formed on the light receiving surface of the CCD 29 for each line (main scanning direction), and the image is read line by line.

As is well known, the CCD 29 has a large number of reading elements arranged side by side in the reading line direction, and an image forming lens 28 is arranged in the optical path on the light receiving surface to form the reflected light from the original. Have been. The image received by each reading element (cell) of the CCD 29 is converted and output into an electric signal (analog signal) corresponding to the light amount, and is converted into a digital signal to be output as read data. The read data (image data) is further processed into data that is reproduced and output by the image forming apparatus as necessary, and is sent to the above-described laser irradiation device 6 as image data.

(First Embodiment of the Present Invention) A first embodiment of a mounting structure of a document table 22 constituting the image reading apparatus 2 according to the present invention will be described below with reference to FIG.

The image reading device 2 as an image scanning device shown in FIG. 4 is provided with a scanning optical system 23 so that an image of a document on the document table 22 is focused on a target position, that is, a light receiving surface of the CCD 29. Have been. Instead of such a configuration, in an analog copying machine, a scanning optical system 23 is provided so that an image of a document on a document table 22 is directly exposed to the exposure position 7 of the photoconductor 4. The present invention is similarly implemented in such an image scanning device, and the following description will be made by taking the image reading device 2 shown in FIG. 4 as an example.

As shown in FIG. 3, the image reading device 2 serves as a reference position for starting reading for aligning the leading end of the document table 22 (upper left side in the figure), particularly one edge (one side) of the document to be placed. The reference plate 30 is provided so as to be covered from above. At the rear end opposite to this, a rear end pressing plate 31 for determining the reading area of the document is provided so as to be covered from above the document table 22 so as to be the final part of the reading of the document. I have.

On the upper surface of the reference plate 30, an index indicating a document placement position, particularly a reference position to be placed according to the document size, is engraved by printing or the like. The operator can easily place the original at a proper position in accordance with the size of the original to be read, using the inscribed index as a mark. In this example, an index indicated by an arrow mark is provided at the upper portion, and the document is placed so that one corner (corner) of the document matches and one edge corresponding to the corner is along the reference plate 30. . This is a one-sided image reading,
Not limited to this, there is a center criterion in which a center is regulated and mounted. In this case, the arrow mark engraved on the upper part is engraved on the central part.

Further, on the operation front side of the image reading device 2, a part of the exterior of the operation panel 32 is similarly covered from above the document table 22 so as to regulate the area on the other side of the document table 22. It is provided. Although not shown, the document cover 20 described with reference to FIG. 4 is pivotally supported on the back side opposite to the operation panel 32 so as to be openable and closable.
In the digital copier, the operation panel 32 is used to display 10 keys for setting the number of copies and the like, keys for setting appropriate copy conditions such as magnification, copy density, double-sided copying, and the number of copies required, the magnification, density, and the like. And a display unit for displaying a trouble state.

Therefore, the reference plate 30 according to the present invention is formed integrally with the exterior cabinet 36 of the image reading apparatus 2 as shown in FIG.
3 and the like, which are not shown in FIG. 3 and are fixed to the support frame 34 shown in FIG.

The support structure will be described with reference to FIG.
The support frame 34 has a recess 35 for positioning and supporting one end of the document table 22. This recess 35
A document table 22 is placed and supported on the document table. Also, the document table 22
Similarly, at the rear end, it is also placed in a recess provided in a support frame (not shown) and positioned and supported.

When the document table 22 is placed in the concave portion 35 of the support frame 34, the reference plate 30
Is covered and screwed on the support surface on the upper part of the support frame 34 with the screw 33, and the document table 22 is fixed in a state of being sandwiched between the concave portion 35 of the support frame 34 and the reference plate 30. This also applies to the rear end side of the document table 22.

Here, according to the present invention, the reference plate 30
As described above, a part of the cabinet constituting the exterior of the image reading apparatus 2 is integrated, and particularly, is integrally molded in resin molding. In particular, as shown in FIGS. 1 and 3, the reference plate 30 is integrated with a part of the exterior 36 of the cabinet perpendicular to the plane (horizontal portion). Strain, deformation, twist, etc. are suppressed during molding. That is, it is reinforced also in terms of strength.

Thus, the reference plate 30 in which a part of the exterior 36 is integrated, in particular, integrated with the cabinet 36 having a vertical portion, is screwed to the support frame 34 as shown in FIG. When fixed and supported,
The reference edge for aligning the originals is not deformed, distorted, twisted, or the like, and satisfactorily contacts the entire surface of the original table 22 without forming any partial floating or gap. Therefore, when the original is aligned with the reference plate 30, it is possible to eliminate the problem that the original enters a gap or a floating portion.

Further, since the reference plate 30 according to the present invention is formed integrally with the exterior of the image reading apparatus 2, it is reinforced in terms of strength. Further, even when the reference plate 30 is formed, distortion, deformation, and the like of the regulated portion of the document can be suppressed as much as possible. Therefore, it is possible to prevent the reference plate 30 from being twisted or deformed when the screws 33 are used to fix the screws. In addition, it is possible to prevent a floating or a gap from being generated between the reference plate 30 and the document table 22, and it is possible to solve the above-described problem. In particular, the reference plate 30 and the like are heated by radiant heat or the like from the exposure lamp 24, and the effect of suppressing plastic deformation or the like due to the heat can be sufficiently expected. That is, it is due to being integrated.

Here, in order to further reinforce the strength of the reference plate 30, a plurality of reinforcing ribs or the like may be partially provided. In particular, ribs may be provided in other portions except for a region covering the document table 22.

When the reference plate 30 is screwed to the support surface 34a of the support frame 34 in FIG. 1, the reference plate 30 may be directly mounted. However, in order to improve the mounting accuracy and the like, the pedestal 37 as a mounting member is used. It may be attached via a. The pedestal 37 is provided at, for example, both ends in the width direction of the document table 22 as shown in FIG. Thereby, the pedestal 37
The reference plate 30 is attached at a contact portion between the reference plate 30 and the support surface 34 a of the support frame 34, so that when the entire area of the reference plate 30 is attached to the support frame 34, deformation occurs according to the support surface 34 a of the frame. Is eliminated.

(Second Embodiment of the Present Invention) According to the first embodiment described above, the reference plate 30 is connected to the image reading device 2.
An example was shown in which it was formed integrally with a part of the cabinet 36 of the exterior for constituting the above. Thereby, distortion, torsion, and deformation due to molding can be suppressed as much as possible, and by attaching the reference plate 30, the reference plate 30 is prevented from partially or entirely forming a gap or floating from the platen 22. I have.

The present invention is not limited to this example. An example will be described below in which the reference plate 30 is attached so that the sides of the reference plate 30 where the originals are aligned are brought into good contact with the original platen 22 to eliminate gaps and floating. .

FIG. 2 is a view for explaining a second embodiment of the present invention.
A pedestal 37 for supporting and attaching the pedestal is integrally provided. The pedestal 37 is conventionally provided in parallel, that is, in a horizontal state, similarly to the support surface 34 a of the support frame 34. In this regard, according to the present invention, the inclined surface 37a is provided such that the surface of the support frame 34 facing the support surface 34a is inclined as shown in the figure. This inclination direction is
The document table 22 is inclined at an inclination angle θ so that the document table 22 is raised.

The pedestal 37 for mounting the reference plate 30 according to the present invention is, as shown in FIGS.
Are provided at positions (two points) further deviated from both ends. The shape of the pedestal 37 is a square prism having a square cross section in FIG. 3, but may be a column.
In short, what is necessary is just to be provided so that it may project to the position shown in FIG.

For this purpose, as shown in FIG. 2A, the document table 22 is placed in the concave portion 35 of the support frame 34, and the reference plate 30 on which the pedestal 37 is integrally formed is placed on the document table 22 from above.
Cover from the top. Then, as shown in FIG. 2 (b), a fixing screw 37 is used to fix the pedestal 37 to the support surface 34 a of the support frame 34 with the screw 33. At this time, the pedestals 37 provided at both ends have the inclined surface 37a facing the support surface 34a of the support frame 34, and the screws 37 are so arranged that the inclined surface 37a is flush with the support surface 34a. Fixed.

As a result, the reference plate 30 is curved so as to bend downward in accordance with the inside, that is, the inclined surface. Therefore, the reference plate 30 is attached so as to be in close contact with the surface of the document table 22. Therefore, even if the reference plate 30 is deformed or distorted at the time of molding, the reference plate 30 is attached so as to be in close contact with the document table 22 as shown in FIG. As in the conventional example shown in FIG.
In addition, partial floating due to deformation or the like is not formed.

In FIG. 2B, only the central portion is shown to be in close contact with the document table 22. However, for simplicity of description, it is only illustrated, and the entire area of the document table 22 is preferably The reference plate 30 can be attached so as to be in contact with the reference plate 30. That is, the dimensions and the like of the pedestal 37 are
0 is set to be in contact with the document table 22. As a result, the reference plate 30 is brought into good contact with the surface of the document table 22 by the urging force that always acts on the surface of the document table 22 upon attachment.

Therefore, regardless of the distortion or deformation of the reference plate 30 during molding, the reference plate 30 can be attached to the document table 22 with as little gap or floating as possible. It is possible to suppress the problem caused by the floating and the formation of the gap.

As described above, by providing the pedestal 37 with an inclination, the dimensional error of the pedestal 37 and the like can be absorbed by the above-described operation, and the design of the reference plate 30 can be made easily and easily. Therefore, it can contribute to cost reduction.

The pedestal 37 is formed integrally with the reference plate 30, but may be formed separately. In this case, the inclined surface 37a formed on the pedestal 37
The reference plate 30 is supported by the support frame 34 so that the
2 as shown in FIG. In this case, the pedestal 37 may be made of elastic rubber or the like instead of resin.

By inclining the pedestal 37 as described above, it is possible to mount the reference plate 30 so as to bend in the direction in which the reference plate 30 is brought into close contact with the document table 22. Therefore, even if the reference plate 30 is formed as a single plate-like reference plate 30 as in the related art without integrating the reference plate 30 with the cabinet 36 constituting a part of the exterior as described in the first embodiment, the present invention Can achieve the purpose. Therefore, in the case where the reference plate 30 is formed by resin molding, the cost of manufacturing the reference plate 30 is naturally greatly reduced.

The angle of the inclined surface 37a of the pedestal 37, that is, the angle θ formed between the inclined surface and the horizontal line as shown in FIG. 2 (a), becomes larger as the angle becomes larger. If it is mounted so as to coincide with the surface 34a, the acting force of bending and bending the reference plate 30 toward the original platen 22 becomes stronger. When the angle θ is small, the acting force of the reference plate 30 bending and bending toward the platen 22 becomes small.

Therefore, by setting the angle θ appropriately, other effects can be defined, and the effect of achieving the object of the present invention can be expected. That is, the acting force of pressing the reference plate 30 and the document table 22 is different depending on the angle.

Referring to FIG. 5, reference plate 30 and platen 22
, That is, the pressing force of the reference plate 30 against the platen 22 will be described. As shown in FIG.
Is attached to the support frame 34 and flexed and pressed against the document table 22 side. Therefore, the platen 2 of the reference plate 30 at that time is
The pressing pressure becomes maximum at the first contact start point c with respect to No. 2 and gradually decreases toward the center. Therefore, the contact start point c at both ends is maximized, and the pressure distribution is curved downward. This is the case where the reference plate 30 is made of a resin, and a rigid body such as a metal (sheet metal or the like) may have a maximum pressure at the center. In other words, in the case of resin, the pressure at the contact point is the highest than the degree of deformation, and the pressure decreases as the distance from the portion to which the screw is fixed increases.

The results of experiments on problems such as floating or gaps of the reference plate 30 that variously change the pressing force of the reference plate 30 by the reference plate 30 as described above will be described below.
In this case, in order to change the pressing force, the pressure contact state of the reference plate 30 changes depending on the dimensions of the pedestal 37 (dimensions on the original table side) and the like, but the dimensions are kept constant and the angle θ of the inclined surface is variously changed. I went.

As a result, the pressing pressure was from 10 g / cm to 50 g / cm.
If the original is within the range of g / cm, the original is
A good result could be obtained without any intervening manuscript, no deformation such as being caused by the heat of the exposure lamp 24 or the like, or damage to the manuscript table 22. In this case, as described with reference to FIG. 5, the pressing force of the reference plate 30 is not constant in the entire area, that is, in the width direction of the document table 22 (the longitudinal direction of the reference plate 30), and the center portion is small and both end portions are large. .

For this purpose, as shown in FIG.
In the pressure distribution over the entire area when the abutment 0 contacts the document table 22, the pedestal
7 may be set to the angle θ of the inclined surface 37a. For example, the characteristic graph A or C is partially set within the above-described range, but in such a case, a problem described below occurs. Therefore, the angle state of the inclined surface 37a of the pedestal 37 may be set so that the characteristic graph B shown in B is obtained.

As described above, the pressing force may be within the above-mentioned range and is a considerably wide range. Therefore, the angle θ of the inclined surface 37a of the pedestal 37 can be set in a wide range, and the design is not correct. Can be accurately covered with the inclined surface 37a.
Is not required, so that the manufacturing cost does not increase.

Here, a problem in the case where the pressure is out of the range of the above-described pressing force will be described. If the pressure of the reference plate 30 against the platen 22 is partially less than 10 g / cm,
The curved state of the reference plate 30 on the platen 22 is small, and there is a case where a document or the like is interposed or dust or the like is mixed. In this case, at least the document should maintain the above-described pressure range within the area of the maximum document reading size as shown in FIG.

When the pressing pressure exceeds 50 g / cm, even if the reference plate 30 is in good contact with the platen 22, the ambient temperature rises, especially the exposure lamp 2.
4 cannot absorb the expansion of the document table 22 or the like, and may cause damage to the document table. Moreover, the reference plate 30 itself is also subject to plastic deformation due to heat at a position where the pressing pressure is strong, and deformation such as warping in the opposite direction occurs, which may cause a gap. For this reason, in the case of pressure characteristics such as A, deformation or further breakage at the contact start point c is predicted, and if possible, the pressure distribution as indicated by B in all contacting regions is expected. Set to be.

Therefore, the pressing force of the reference plate 30 against the document table 22 may be set so as to fall within the above range, and the angle θ of the inclined surface of the pedestal 37 may be set so as to fall within the range. Here, the angle θ of the inclined surface 37a is
, The dimensions on the side of the document table 22 are set to be constant, but naturally the angle is also changed by making the dimensions on the opposite side constant and changing the document table 22 side variously. Therefore, setting the angle θ appropriately is to adjust one dimension (height) of the pedestal 37, which also slightly changes depending on the material of the reference plate 30, its thickness, and the like. The effect described above can be expected by adjusting in a suitable state.

In the description of the second embodiment, the pedestal 37
It has been described that the inclined surface 37a is formed on the side, but the support surface 34a side of the support frame 34 is also inclined in the same manner, and the pedestal 37 is formed in a flat surface, that is, in a horizontal state without the inclined surface 37a You may make it. In this case, the inclination of the support surface 34a of the support frame 34 is formed such that the document table 22 side is lowered in FIG. Thus, the reference plate 30 is attached with the screws 33 so that the surfaces of the pedestals 37 on the reference plate 30 coincide with each other, so that the reference plate 30 is bent downward and abuts on the document table 22 side.

In this embodiment, the reference plate 3
0 is formed in a flat plate shape as an example, but as described in the first embodiment, the vertical portion of the cabinet 36 that is a part of the exterior of the image reading device 2 is replaced with the reference plate 3.
If it is made to be integrally molded with 0, the reference plate 3 at the time of molding
It is possible to eliminate zero distortion, deformation, and the like, and to further improve the adhesion to the document table 22. Therefore, more excellent effects can be expected by the combination according to the first and second embodiments.

(Other Embodiments of the Present Invention) According to the above-described first and second embodiments, in order to read an image of an original, the operator places the original at a predetermined position, and The original is optically scanned and read using the scanning optical system 23.

Instead of reading such an image, there is also one that reads while transporting a document. That is, in the image reading apparatus 2 shown in FIG. 4, the scanning optical system 23 is fixed at the position shown in FIG. What is read every time is well known. Further, the image reading device 2 is provided with an automatic document conveying device, and the image can be read by forming an image on the CCD 29 by the optical system 23 fixed at the time of conveying the document.

When reading an image while transporting a document as described above, the reference plate 30 shown in FIG. 3 and the like also needs to have a function of scooping up the read document. That is, as shown in FIG. 7, on the document table 22, an automatic document feeder including a transport means 38 for automatically transporting the document is detachably provided. That is, it is mounted when reading while transporting the original. Alternatively, an automatic document feeder may be used in which the document is conveyed and stopped along the reference plate 30, and in this state, the scanning optical system 23 provided below is scanned and read.

In FIG. 7, a document conveying means 38 includes a feeding means (not shown) for feeding one sheet, a guide 39 for guiding the document sent by the feeding means to the surface of the document table 22, It is provided with a white plate 40 and the like provided to oppose the original reading position a so that the original to be conveyed is brought into close contact with the surface of the original platen 22. The exposure lamp 24 and the reflection mirror 25 of the scanning optical system 23 are stopped at the position corresponding to the reading position a. Also,
Although not shown, the other reflecting mirrors 26 and 2 shown in FIG.
7 is also stopped, and CC is passed through the imaging lens 28.
An image is formed on the light receiving surface of D29.

After passing through the reading position a, the original conveyed in the direction of the arrow is picked up by the reference plate 30, here, the original picking-up member 30, so as to be peeled off from the surface of the original platen 22. The paper is sent to the paper output tray. A discharge roller or the like for that purpose is provided.

In such a configuration, the conveyed original is read from the original table 22 by the reference plate 30 serving as a pick-up member after the original is read, and is discharged. At this time, if there is a gap between the reference plate 30 and the document table 22, the document enters the gap, hinders the conveyance of the document, and causes jamming, that is, a jam. When a document is conveyed due to the jam, the document may be caught, bent, or torn.

In order to solve such a problem, the scooping member 30 can also be solved by mounting it as described in the first and second embodiments. In other words, according to the scooping member 30 serving as the reference plate, since a gap or floating between the document table 22 and the document table 22 is prevented as much as possible, problems such as jamming of the conveyed document at that position and jamming are eliminated. Then, the read document can be picked up and discharged.

At this time, as shown in FIG. 7, the edge of the scooping member 30 is gradually inclined from the side where the document is conveyed by three.
0a is formed at an acute angle. Thus, the inclined surface 30
By providing a, it is possible to promote the effect of reducing the jamming of a document.

Therefore, according to the present invention, even when a document is read with the document placed at the reference position or when the document is read while being transported, the document enters between the reference plate 30 and the document table 22 and is damaged. And the occurrence of jams and the like can be eliminated. When the original is read while being conveyed, an inclined surface 30a is attached to the edge of the scooping member 30 which is the reference plate.
Is provided, the occurrence of document jam can be suppressed.

Although the embodiments have been described above, the image reading device 2 reads the image of the original by using the CCD 29 as a reading element.
Are scanned so as to form an image on the light receiving surface, and an image based on the examination is read. According to the present invention, not limited to such a device, the photosensitive member 4 for directly forming an image on the reflected light of the document
Needless to say, the present invention can also be applied to a scanning device that performs scanning so as to form an image. Further, even when the document is conveyed in order to form an image of the document, the configuration described with reference to FIG. 7 can be used as it is.

Further, in an OHP or the like, a transparent sheet is placed on a transparent platen and the transparent sheet is projected on a target position, that is, on a screen or the like.
In the case where is provided, it is a matter of course that the present invention can be applied. That is, when a frame or the like indicating a mounting area is provided on a platen on which a transparent OHP sheet is mounted,
The effect of preventing the OHP sheet from entering between the frame and the platen can of course be expected.

[0092]

According to the image scanning apparatus of the present invention described above, a gap or a float formed between a document table on which a document is placed and a reference plate indicating a reference position of the document to be placed is determined. As much as possible, it is possible to prevent the original from being caught or a foreign substance from entering.

In particular, if the reference plate is formed so as to be integrated with a part of the exterior of the image reading apparatus, the reference plate is unlikely to be distorted or deformed. Can be suppressed.

Further, since the reference plate is bent toward the platen surface side by providing an inclined surface to a mounting member for mounting the reference plate, the adhesion of the reference plate to the platen is improved, so that there is a gap or partial area. Floating can be prevented. In this case, the reference plate can be brought into good contact with the document table without being affected by distortion, deformation, or the like at the time of molding the reference plate, and a problem caused by a gap or floating can be solved. In particular, it is possible to absorb deformation of the reference plate due to radiant heat or the like during optical scanning.

Further, as described above, the reference plate can be satisfactorily brought into contact with the platen without increasing the mounting accuracy of the reference plate and the design accuracy of the members to be mounted. In addition, the manufacturing process is simplified by integrating the reference plate and the exterior, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing an attached state of a document table and a reference plate constituting a document reading apparatus which is an image scanning apparatus for explaining a first embodiment of the present invention.

FIG. 2 illustrates a state of attachment between a platen and a reference plate constituting a document reading apparatus which is an image scanning apparatus for explaining a second embodiment of the present invention, which is viewed from the right side in FIG. (A) is a diagram showing a deployed state before assembly, and (b) is a diagram showing an assembled state.

FIG. 3 is a perspective view showing an external configuration of the image reading apparatus according to the present invention and showing a state in which each component constituting the apparatus is developed.

FIG. 4 is a configuration diagram illustrating a schematic configuration of an entire digital copying machine as an example of an image forming apparatus including the image reading device of the present invention.

FIG. 5 is a diagram for explaining a pressing force state of a reference plate against a document table according to a second embodiment of the present invention, and is a diagram particularly showing a distribution characteristic of a pressing force.

FIG. 6 is a characteristic diagram illustrating a distribution characteristic of a press-contact state between a reference plate and a document table according to a second embodiment of the present invention, and illustrating a favorable press-contact range.

FIG. 7 is a diagram for explaining an example in which the present invention is implemented by a method of reading a document while conveying the document in the image reading apparatus.

FIG. 8 is a side view showing an attached state of a reference plate and a document table in a conventional image reading apparatus.

9A and 9B are views showing a state of attachment between a reference plate and a document table in a conventional image reading apparatus, wherein FIG. 9A is a view showing a developed state before assembling, and FIG. 9B is a view showing an assembled state.

[Explanation of symbols]

 2 Image Reading Device 20 Document Cover 22 Document Plate 23 Scanning Optical System 24 Exposure Lamp 25 Reflection Mirror 29 CCD (Reading Element) 30 Reference Plate (Rip Up Member) 31 Pressing Plate 33 Fixing Screw 34 Support Frame 34a Support Surface 35 Depression 36 Exterior (cabinet) 37 Pedestal 37a Inclined surface θ Inclined angle 38 Document conveying means 39 Guide 40 White plate

Claims (7)

[Claims] 1. An image scanning apparatus comprising an optical system that optically scans an original on a platen and forms an image of the original on a desired position. A reference plate indicating a reference position of the original on the platen. Wherein the reference plate is integrated with a cabinet forming a part of the exterior of the image scanning device. 2. The image scanning device according to claim 1, wherein the cabinet has a vertical exterior in a direction orthogonal to a plane portion of the reference plate. 3. An image scanning apparatus comprising an optical system for optically scanning a document on a document table and forming an image on a desired position, a reference plate indicating a reference position of the document on the document table. Is fixed to the support surface of the support frame from the upper part of the supported document table, a mounting member for fixing the reference plate so as to bend and bend toward the document table surface side is provided, and the mounting member and the support surface are provided. An image scanning device characterized in that they are matched in an inclined state. 4. The mounting member is a mounting pedestal provided integrally with the reference plate, and the pedestal is provided with an inclined surface inclined with respect to a support surface of a support frame. 4. The image scanning device according to claim 3, wherein: 5. The image scanning device according to claim 3, wherein the reference plate forms a part of an exterior of the image scanning device, and is a vertical exterior in a direction orthogonal to a plane portion of the reference plate. apparatus. 6. The inclined surface formed on the pedestal of the mounting member has an inclination angle in a range of 10 g / cm to 50 g / cm when the reference plate bends and abuts on the document table side. 5. The method according to claim 4, wherein
An image scanning device according to claim 1. 7. The image scanning device forms an image sequentially at a desired position while transporting a document. The reference plate is a pick-up member having a function of peeling the imaged document from a document table. 4. The image scanning device according to claim 1, wherein an inclined portion is provided at an edge of the reference plate.