JP2003344957A - Image reading device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading device wherein the open/closed state of a document cover is detected with an inexpensive constitution using the existing optical means, and then, the drive of an automatic document feeder is stopped, and also, the breakage of the document is prevented and also image information is accurately read. <P>SOLUTION: As for the image reading device A wherein several documents are successively fed by an RSPF 20, and the image information of the document is read as image data by a scanner unit 2 having a CCD 27, and provided with the opening/closing document cover 12 for covering the document to be read, two black line marks 11a and 11a are put on a plate to be detected 11 with an appropriate distance between the marks, and by reading the marks by the CCD before feeding the document to the reading position, the open/closed state of the document cover is detected, and in the case of detecting that the document cover is open, the document feeding rollers 13 and 13 of an upstream document feeding means 10 and a pair of upstream reading/carrying rollers 15 and 15 are stopped and a pair of downstream reading/carrying rollers 19 and 19 of the document feeding means 10b on the downstream side and a pair of document discharging rollers 16 and 16 are continuously driven. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus for reading image information of an original in a copying machine or a scanner device, and more particularly to an apparatus having an automatic original conveying apparatus.

[0002]

2. Description of the Related Art An image reading device provided in a copying machine or a scanner device is equipped with an ADF (Automatic).
Document Feeder), SPF (Sing)
Some include automatic document feeders such as a lePass feeder). In such an image reading apparatus, a document cover that covers the upper part of the image reading unit can be opened and closed so that the document can be easily removed when a paper jam such as a document feeding error occurs. is there. With such a configuration, the document jammed by the image reading device can be easily removed.

However, when an image reading operation is performed with the document cover open or half-opened, external light rays enter through the gap between the main body of the apparatus and the document cover, or defocus occurs. there's a possibility that. This causes a problem that the image is not accurately read, and it is necessary to detect the open / closed state of the document cover. In order to perform this detection, it is necessary to provide a micro switch for detecting the open / closed state of the document cover, which causes a problem of high production cost.

From this point of view, conventionally, a reference line for determining the original reading range by the image reading means is provided at a position facing the image reading means, and the reference line is recognized by the image reading means when the power is turned on. An image reading apparatus has been proposed which can confirm whether the document cover is closed (see Japanese Patent Laid-Open No. 8-328447).

[0005]

By the way, in the image reading apparatus provided with the automatic document feeder as described above, not only the image information of a plurality of sheet originals is read using the automatic document feeder, but also a book original or the like. In some cases, the document that cannot be automatically conveyed is directly placed on the document table to read the image information.

As described above, after the original document that cannot be automatically conveyed is read, the original document is forgotten to be removed from the original document placing table, and the image information of the sheet original document is read in that state, the original document cover is read. Documents are fed automatically when is not completely closed. In addition,
In some cases, the document may be set on the automatic transport device and the image reading may be started by mistake when the document cover is not completely closed.

In this case, not only the image is not accurately read, but also the paper document is not properly automatically conveyed, and there is a risk that the paper jam occurs and the document is torn.

Therefore, when the original document is automatically conveyed with the book original document or the like placed on the original table or in the floating state without the original cover being completely closed, the original cover is opened. Therefore, it is necessary to stop the driving of the automatic document feeder by determining that the document cover is open by the above-described micro switch.

However, when such a micro switch is used, there is a problem that the production cost becomes high as described above.

The present invention has been made in view of the above circumstances, and an object thereof is to detect an open / closed state of a document cover with an inexpensive structure using existing optical means, and to automatically transport the document. An object of the present invention is to provide an image reading device which can stop the driving of the document, prevent damage to the document, and accurately read the image information.

[0011]

In order to achieve the above object, according to the present invention, a plurality of sheet originals are sequentially conveyed by a conveying means such as an ADF and an SPF as an image reading device provided in a copying machine, a scanner device and the like. However, it is premised that the image information of the original document is read as image data by the optical means having the CCD and the original document cover provided with the openable / closable original document cover is read. A mark is provided on the document cover, and the mark is read by the optical means before the document is conveyed to the reading position, whereby the open / closed state of the document cover is detected by the detection means, and the document cover is opened. When the state is detected, the conveyance stop means stops the driving of the conveyance means to stop the conveyance of the document.

Due to this specific matter, the reference position or reference level of the mark when the document cover is normally closed (for example, when the apparatus is turned on or the initial state of the apparatus) and the mark when the document is read are displayed. By comparing with the position, the document cover is not completely closed when reading the document, or it is in the open (floating) state due to the book document being placed, or it is closed. It will be detected whether it is in a state. Then, when the document cover is open (floating), the driving of the conveying means is stopped. Therefore, even if the document cover is erroneously lifted and the document reading operation start is instructed, the conveying unit is not driven, and thus the document can be prevented from being damaged. Further, it is possible to avoid the risk that the image data cannot be accurately read, which may occur when the document is conveyed with the document cover in a floating state. Further, according to such a configuration, a new configuration is added by detecting the positional deviation of the mark and the change in the detection level of the mark by using the existing optical means having the CCD in the image reading apparatus. It is possible to detect the open / closed state of the document cover easily and at low cost.

In particular, the following constitutions are provided to detect the opening / closing of the opening / closing cover more accurately.

That is, a plurality of marks are provided within the maximum readable range of the maximum document width of the document cover.

By reading a plurality of marks according to this specific matter, it is possible to reliably detect the marks and reliably detect the floating of the document cover. Also,
Since all the marks on the document cover are wider than the maximum document width and within the maximum readable range, the marks can be read regardless of whether or not the document is read, and the relative positions of the CCD and the document cover are displaced. Even in such a case, since the mark interval is set wide, the change in the mark interval can be reliably recognized, and the floating of the document cover can be detected more accurately.

In particular, the following configuration is given as a specific example of detection of opening / closing of the document cover by the detection means.

That is, the marks are detected by the detecting means by the inner spacing between the peaks corresponding to the plurality of marks in the output waveform of the optical means, or the edge spacing. The mark is detected by the detection means based on the inner space.

Due to this specific matter, when a mark such as a line or a dot is read by the CCD which is an optical means, a peak corresponding to the mark appears in the output waveform, but this peak is
When the optical means is in focus, that is, when the document cover is securely closed, it has a sharp shape, and when it is not in focus, it has a blunt shape. Therefore, at the inner distance between the peaks or the edge distance, floating detection is performed in a state relatively close to the in-focus state. If it cannot be detected by this, the peak interval is measured, and as shown in FIG. 3, the peak interval is shifted depending on the opening degree of the document cover, so that a relatively large float outside the depth of field occurs. Will be detected. Therefore, it becomes possible to easily detect the floating of the original cover without processing the output waveform of the CCD.

If a mark is provided within the range of the maximum document width of the document cover and the opening / closing state of the document cover is detected by the detecting means before the document is conveyed or between pages of the document, the mark is set. Is reliably detected, and it becomes possible to stably detect the floating of the document cover. Also, since the marks on the document cover are within the maximum document width of the document cover, the marks are read before each document is conveyed, and changes in the mark interval are reliably recognized to ensure stable document cover operation. It becomes possible to detect floating.

In particular, the following constitutions are provided for speedily detecting the mark.

That is, a mark is provided at or near the home position of the optical means.

Due to this specific matter, the mark is provided near the home position of the optical means, that is, in the vicinity of the fixed position where the optical means is located when the image reading device is in the standby state, and the mark is immediately detected. By opening the original cover open / close detection timing earlier, the recovery process becomes faster and the original can be prevented from being damaged.

Further, when the home position of the optical means and the document reading unit are provided at positions opposite to each other, if a marker is attached to each of the home position and the document reading unit, a mark is added. By providing the optical unit at the home position (fixed position), the mark can be detected immediately. Further, by providing it in the document reading section of the automatic document feeder such as SPF, the open / closed state of the document cover can be detected even when the document is being transported. Therefore, by providing the marks at the home position and the document reading portion, respectively, the opening / closing detection timing of the document cover is accelerated, the recovery process is accelerated, and it is possible to quickly prevent the document from being damaged.

In particular, the following configurations are provided to reduce the burden on the operator due to the occurrence of jams during document transportation.

That is, when the open state of the document cover is detected by the detecting means, the document conveying means on the upstream side of the document reading section is stopped and the document conveying means on the downstream side of the document reading section is continuously driven. I am trying to let you.

Due to this particular matter, most of the troubles (jams) in the document conveyance are paper feed errors when the document is picked up by the paper feed rollers from the document placing table. In such a case, all the document conveyances are performed. If this is stopped, it will take time and effort to take out the original near the original reading unit. However, even if a trouble occurs in the original conveyance, the original conveying means on the upstream side of the original reading unit where the trouble occurs The conveyance of the (pickup roller unit) is stopped, and the original document remaining in the vicinity of the reading unit is completely read, and is ejected to the original document ejection unit by the document conveyance unit downstream of the original document reading unit, thereby jamming the jam. It is possible to reduce the burden on the operator due to processing or the like.

In particular, the following constitutions are given to determine the lighting timing of the light source of the optical means.

That is, the lighting timing of the light source of the optical means is determined based on the moving time of the optical means and the light source stabilization time during which the light source stabilizes.

According to this particular matter, when the optical means stands by at the home position in which the optical means conflicts with the original reading portion at the time of power-on or when the reading of the original is completed, the original is read from the home position. By determining the lighting timing of the light source of the optical means on the basis of the moving distance and the moving speed to the unit, the light amount of the light source is stabilized, and the image can be read immediately after the movement of the optical system is completed. .

Further, as a means for eliminating the uncomfortable feeling caused by the addition of the mark, the following constitutions are listed.

That is, when an optical means capable of reading a color image is applied, a color that is difficult for human eyes to recognize is used for the mark.

According to this specific matter, if the mark such as a line or a dot is formed in a color such as yellow that is difficult for the human eye to recognize, it becomes possible to surely recognize the mark by Y (yellow) of the color CCD. If the mark is yellow, it is difficult for the human eye to recognize, so that the operator does not feel uncomfortable even when the document cover with a white back is opened.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

The image reading apparatus according to the present invention is provided in an apparatus that performs image processing such as a copying machine and a scanner, and reads image data of an original in order to perform processing according to various purposes. Has the function of performing.

FIG. 1 is a side view of an automatic document feeder (RSPF; Reversing Single) according to the present invention.
FIG. 3 is a cross-sectional view showing a configuration of a digital copying machine 1 including an image reading device provided with a Paper Feeder). The main body of the digital copying machine 1 is roughly divided into an image reading apparatus A and a laser recording section B.

The image reading apparatus A is an original placing table 21 as an original reading section made of transparent glass, and a double-sided automatic original feeding apparatus 20 (RSPF: conveying) for automatically supplying and conveying an original on the original placing table 21. Means) and a document image reading unit for scanning and reading an image of a document placed on the document table 21, that is, a scanner unit 2 (optical means).

The original image read by the image reading apparatus A is sent to the image data input unit as image data, and the image data is subjected to predetermined image processing.

In the RSPF 20, a plurality of originals are set on the original tray 22a provided at one time,
This is an apparatus for automatically feeding the set originals one by one onto the original placing table 21 located on the scanner unit 2. Further, the RSPF 20 passes through a conveying path for a single-sided original, a conveying path for a double-sided original, a conveying path switching unit, and each unit so that the scanner unit 2 can read one side or both sides of the original according to the operator's selection. It is composed of a sensor group that grasps and manages the state of the document to be processed, a control unit that controls conveyance, and the like. RSPF2
The detailed configuration of 0 is as described later.

The scanner unit 2 for reading an image of a document on the document table 21 guides a lamp reflector assembly 24 that exposes the surface of the document and a reflected light image from the document to a photoelectric conversion element 27 (CCD). First scanning unit 23a having a first reflecting mirror 25a that reflects the reflected light from the original document, and a reflected light image from the first reflecting mirror unit 23a is converted into a photoelectric conversion element 27 (CC
Second and third reflecting mirrors 25b, 2 for leading to D)
A second scanning unit 23b equipped with 5c and a photoelectric conversion element 27 (C which converts a reflected light image from a document into electric image data via the respective reflection mirrors 25a to 25c.
Optical lens 26 for forming an image on a CD), and the above-mentioned C for converting a reflected light image from a document into electric image data.
And a CD 27. The CCD 27 is
It also has a function as a detection means for detecting the open / closed state of the document cover 12 based on an output waveform obtained by reading marks 11a, 11a (described later) provided on a detection target plate 11 provided in the RSPF 20 described later. . In this case, the first and second scanning units 23 of the scanner unit 2
The home positions of a and 23b are located at the end opposite to the plate to be detected 11 (right end in FIG. 1).

The image reading apparatus A causes the scanner unit 2 to move along the lower surface of the document placing table 21 while sequentially placing the documents to be read on the document placing table 21 by the related operations of the RSPF 20 and the scanner unit 2. Is moved to read the original image.

In particular, the first scanning unit 23a travels along the document table 21 from left to right at a constant speed V, and the second scanning unit 23b moves relative to the speed V of the first scanning unit 23a. Scan control is performed in parallel in the same direction at half the speed V / 2. As a result, the image of the original document placed on the original document table 21 is sequentially line-by-line CCD 27.
The image is read by forming an image.

Then, the image data obtained by reading the original image with the scanner unit 2 is sent to an image processing section, which will be described later, and subjected to various processing, and then temporarily stored in the memory of the image processing section. In response to the output instruction, the image in the memory is read and transferred to the laser recording unit B to form the image on the recording sheet P.

The laser recording section B includes a conveyance system for a recording sheet P for forming an image, a laser writing unit 31, and an electrophotographic process section 32 for forming an image.

The laser writing unit 31 is a semiconductor laser light source that emits laser light according to image data read from the memory after being read by the scanner unit 2 or image data transferred from an external device, a laser. It has a polygon mirror for deflecting light at a constant angular velocity, an f-θ lens for correcting laser light deflected at a constant angular velocity so as to be deflected at a constant angular velocity on the photosensitive drum 33 constituting the electrophotographic process section 32, and the like. ing.

In the electrophotographic process section 32, a charging device 34, a developing device 35, a transfer device 36, a discharging device 38, a peeling device, a cleaning device 37 and a fixing device 39 are arranged around the photoconductor drum 33. Made of The charger 34 charges the surface of the photoconductor drum 33 before the electrostatic latent image is formed to a predetermined potential. The developing device 35 is
The electrostatic latent image formed on the surface of the photoconductor drum 33 is developed into a visible image with toner. The transfer device 36 transfers the toner image formed on the surface of the photosensitive drum 33 to the recording sheet P. The fixing device 39 fixes the toner image transferred to the recording sheet P on the recording sheet P by heating. The static eliminator 38 is the photosensitive drum 3
3 is to remove the residual charge on the surface. The peeling device and the cleaning device 37 are configured to remove the toner remaining on the surface of the photosensitive drum 33 after the toner transfer.

As a result, when forming an image on the recording sheet P, the surface of the photosensitive drum 33 is charged to a predetermined potential by the charger 34, and the laser writing unit 31.
Irradiates the surface of the photoconductor drum 33 with laser light based on image data to form an electrostatic latent image. After that, developing device 3
5 develops a visible image with toner on the surface of the photoconductor drum 33, and the toner image is transferred by the transfer device 36 to the recording sheet P fed from the conveying system of the recording sheet P. Then, the recording sheet P is heated by the fixing device 39 and the toner image is fixed. On the other hand, the photosensitive drum 3
The residual charge on the surface of No. 3 is removed by the static eliminator 38, and the toner remaining on the surface of the photoconductor drum 33 is removed by the peeling device and the cleaning device 37. As a result, one of the image forming operations (printing operations) on the recording sheet P is performed.
The cycle ends. By repeating this cycle, it is possible to continuously form images on a plurality of recording sheets P, P, ....

On the other hand, the transport system of the recording sheet P is the transfer device 3 of the electrophotographic process section 32 for performing the above-mentioned image formation.
A conveyance unit 46 that conveys the recording sheet P to the transfer position where 6 is arranged, a cassette sheet feeding device 41, 42, 43 for feeding the recording sheet P to the conveyance unit 46, or a recording sheet P of a required size. A manual sheet feeding device 44 for appropriately feeding a sheet, a fixing device 39 for fixing an image formed on the transferred recording sheet P, particularly a toner image, and an image is formed again on the back surface of the fixed recording sheet P. For recording sheet P
And a re-supply path 45 for re-supplying.

On the downstream side of the fixing device 39, there is arranged a post-processing device 40 that receives a recording sheet P on which an image has been recorded and performs a predetermined process on the recording sheet P.

In the laser writing unit 31 and the electrophotographic process section 32, the image data read from the image memory is converted into an electrostatic latent image on the surface of the photosensitive drum 33 by scanning the laser beam by the laser writing unit 31. The toner image formed and visualized by the toner is electrostatically transferred and fixed on the surface of the sheet conveyed from one of the sheet feeding units of the multi-stage sheet feeding unit.

The recording sheet P on which the image is formed in this manner is conveyed from the fixing device 39 to the inside of the post-processing device 40 via the paper discharge roller 47.

Next, the detailed configuration of the RSPF 20 will be described with reference to FIG. FIG. 2 is a cross-sectional view showing the configuration of the image reading apparatus A.

The RSPF 20 has a document tray 22a,
Document transport rollers 13, 13 and transport path switching means 1
4, 14, detected plate 11, upstream side reading and conveying roller pair 1
5, 15, downstream reading / conveying roller pairs 19 and 19, document discharging roller pairs 16 and 16, switching tray 17, document discharging tray 18, document placing table 21, and a sensor group and a control unit (not shown). Among them, the document conveying rollers 13 and 13, the upstream side reading conveying roller pair 1
5, 15, the downstream side reading / conveying roller pair 19, 19 and the document discharging roller pair 16, 16 constitute a conveying means 10. The conveying means 10 includes the original conveying rollers 13, 13 and the upstream side reading / conveying roller pair 15 ,. An original conveying means 10a having an upstream side of the original placing table 21 for conveying the original placed on the original tray 22a to the original placing table 21, and a pair of downstream side reading and conveying rollers 19, 19 and 15. The document placing table 2 having the document discharge roller pairs 16 and 16
It is composed of a document conveying means 10b which conveys the document on 1 to the document discharge tray 18 and which is located downstream of the document placing table 21.

The original tray 22a is a tray for placing originals to be copied, and when a plurality of originals are stacked and placed,
The sheets are automatically conveyed one by one, and the images are sequentially read. The original document placed on the original document tray 22a is conveyed by the original document conveyance rollers 13, 13 and the reading conveyance roller pair 15, 15, and the lower portion of the detection target plate 11 provided between the two reading conveyance rollers 15, 15. And is conveyed to the document table 21. The image of the original document conveyed to the original document table 21 is read by the first scanning unit 23a. In the case of a one-sided original, the image of the original is read in the above-described process, and then the original is discharged to the original discharge tray 18 by the pair of original discharge rollers 16 and 16. On the other hand, in the case of a double-sided original, a path for transporting to the switching tray 17 is created by the transport path switching means 14, 14, the original is once discharged to the switching tray 17, and then the detected plate 1 is again detected.
Reading is performed on the surface opposite to the surface that has been previously read by passing the lower part of 1.

Further, the sensor group grasps the state of the document passing through each part of the RSPF 20 and sends it to the control part as an electric signal. A control unit (not shown) switches the transport path switching means 14, 14 in accordance with an electrical signal from the sensor group and a reading mode such as double-sided reading or single-sided reading, and the original feeding rollers 13, 13, upstream side, and the like. Downstream side reading / conveying roller pair 15, 15, 19, 1
9. The drive of the pair of document discharge rollers 16 and 16 is controlled. Further, when it is detected in the scanner unit 2 that the document cover 12 is open, the control section further feeds the document transport rollers 13, 13 and the upstream and downstream reading and transport roller pairs 15, 15, 19, 19. It also has a function as a conveyance stopping means for stopping the driving of the pair of document discharge rollers 16, 16. In particular, when the control section detects the open state of the document cover 12 when automatically transporting a plurality of documents stacked on the document tray 37 one by one,
The upstream-side document transport means 10a, that is, the document transport roller 1
3, 13 and the upstream side reading and conveying roller pair 15, 15 are stopped, and the downstream side document conveying means 10b, that is, the downstream side reading and conveying roller pair 19, 19 and the document discharging roller pair 16,
16 is controlled to be continuously driven.

A document cover 12 is provided on the document placing table 21, and the RSPF is provided inside the document cover 12.
20 are installed. Further, the original cover 12 is
The document table 21 can be covered. Document cover 1
One of the ends of the document placing table 21 is connected by a hinge, and the document 2 can be opened and closed at the other end opposite to the connected one. With the above configuration, when a paper jam such as a document feeding failure occurs in the RSPF 20, the document cover 12 can be opened to remove the document jammed inside.

Further, since the image reading apparatus A can open the document cover 12 as described above, for a document which cannot be automatically conveyed by the RSPF 20, such as a book document, the document is placed. Table 21
The image can be read by placing the original directly on the.

Further, as shown in FIG.
Two marks 11a and 11a (black lines) are attached to the item 1. In the digital copying machine 1, the two marks 11a and 11a are read by the scanner unit 2 immediately before the document is set on the document tray 22a and the document reading operation is executed. Since the detection target plate 11 is installed in the RSPF 20 inside the original cover 12, as shown in FIG.
Go up and down in the direction. In FIG. 4, the two marks 11a, 11a provided on the plate to be detected 11 are imaged on the CCD 27 in the scanner unit 2 when the document cover 12 is in the open state and the closed state, respectively. It is the schematic diagram which showed.

Next, a method of detecting the open / closed state of the document cover 12 by the CCD 27 will be described.

When the original cover 12 is opened more than a predetermined amount and when the original cover 12 is open, the CCD
The waveforms output from 27 are different. That is, the original cover 1
When 2 is in the closed state, the plate 11 to be detected is in substantially the same position as the reading surface of the document, and therefore the optical lens 26 is in focus.

Therefore, the output waveform obtained by the CCD 27 becomes the same as the state in which the marks 11a, 11a (black lines) are added to the original (that is, the output waveform having two sharp peaks). .

On the other hand, when the original cover 12 is opened to a predetermined amount or more, it is outside the depth of field of the CCD 27, and as shown in FIG. The output waveform to be output is a waveform having two blunt peaks, or the mark 11
In some cases, a and 11a cannot be recognized.

Due to such a difference, the open / closed state of the document cover 12 can be surely recognized.

If the opening amount of the document cover 12 is not more than the predetermined amount, the CCD 27 has a deep depth of field, so that even if the document cover 12 is open, the marks 11a and 11a will be removed as shown in FIG. It becomes possible to recognize in a sharp state. In other words, the two marks 11a and 11a are separated when the document cover 12 is open and when it is closed.
Since the position is shifted, the interval between two peaks of the output waveform obtained by the CCD 27 is also different (the peak interval is narrower in the open state than in the closed state). Therefore, the open / closed state of the document cover 12 can be detected from the interval between the two peaks.

If the CCD 27 detects that the original cover 12 is closed, the original cover 12 is recognized as being in a normal state, and automatic conveyance is started to read the original image. On the other hand, if the CCD 27 detects that the document cover 12 is in the open state, the document cover 12 is recognized as being in an abnormal state, the user is warned to that effect, and the control unit stops driving the RSPF 20. Is sent. As a result, the document transport rollers 13,
The driving of 13, the pair of reading / conveying rollers 15 and 15 and the pair of document discharging rollers 16 and 16 is stopped, and the document is not conveyed.

Therefore, it is possible to prevent the document cover 12 from being automatically conveyed while the document cover 12 is mistakenly left in a floating state due to forgetting to take a book document on the document table 21 or the like. Therefore, when the document cover 12 is in a floating state, it is possible to avoid that the image of the document is not accurately read or that the document is not normally conveyed and damaged.

When a plurality of originals stacked on the original tray 37 are automatically continuously conveyed one by one, when the open state of the original cover 12 is detected, the upstream originals are conveyed. The means 10a (original conveying rollers 13 and 13 and the upstream side reading and conveying roller pair 15, 15) is stopped, and the downstream side document conveying means 10b (downstream side reading and conveying roller pair 19,
19 and the document discharge roller pair 16, 16) are continuously driven, so that the document remaining in the RSPF 20 can be read as the document remaining in the read document discharge tray 18 without stopping the conveyance of other documents that are not related to a paper feed error. Therefore, the original can be copied again only by performing maintenance on the original for which the paper feed error has occurred.

The present invention is not limited to the above embodiment, and includes various other modifications.
For example, in the above embodiment, in order to reliably detect the open / closed state of the document cover 12, two marks (black lines) 11a,
Although 11a is attached to the plate 11 to be detected at an appropriate interval, the distance between the two marks (black lines) may be greater than or equal to the maximum document width and within the maximum readable range. In this case, the marks can be read regardless of the presence or absence of the read document, and even if the relative position between the CCD and the document cover is displaced, the mark interval is set wide, so that the change in the mark interval can be reliably recognized. Therefore, the floating of the document cover can be detected more accurately.

On the other hand, the mark may be provided within the range of the maximum document width or less so that the open / closed state of the document cover can be detected by the CCD before the document is conveyed or between pages of the document. In this case, the detection of the mark is surely performed, and stable floating detection of the document cover can be performed. In addition, since the mark on the document cover is within the maximum document width of the document cover, the mark is read before each document is conveyed, and the change in the mark interval is reliably recognized to ensure stable floating of the document cover. Detection can be performed.

Further, in the above embodiment, the shape of the two marks is a line, but the present invention is not limited to this, and the mark may have another shape, for example, a dot. Moreover, although the number of marks is two in the above embodiment, the present invention is not limited to this, and a single mark or three or more marks may be provided.

In the above embodiment, the mark 11
Although a and 11a are represented by black lines, when the photoelectric conversion element (CCD) for converting the reflected light image from the original into electric image data is a color readable photoelectric conversion element (CCD), the back surface is By adding a mark on the white plate to be detected that is difficult for the human eye to recognize, such as yellow, the operator's discomfort when the document cover is opened when the document is placed etc. is eliminated. can do. In that case, a color-readable photoelectric conversion element (CCD) recognizes a color image by individually recognizing R (red) G (green) B (blue). Therefore, when the mark is yellow, the photoelectric conversion element is The mark can be recognized by reading the mark with R and G.

In addition, in the above embodiment, the shape and size of the mark are set to be as small and inconspicuous as possible so as not to make the operator feel uncomfortable. However, it is inconspicuous to the operator by using the color. Any size or shape may be used so long as it is easy to control.

Further, in the above embodiment, the marks 11a and 11a are provided on the detected plate 11 at the ends of the scanner unit 2 opposite to the home positions of the first and second scanning units 23a and 23b. A mark may be provided at or near the home position of the optical means. In this case, the mark is provided near the home position of the first and second scanning units, that is, near the fixed position where the first and second scanning units are located when the image reading device A is in the standby state. Since the mark is immediately detected and the opening / closing detection timing of the document cover is advanced, the recovery process is accelerated and the document can be prevented from being damaged. In addition, when the home positions of the first and second scanning units and the detected plate (image reading unit 21) are provided at positions opposite to each other, markers are provided at the home position and the document placing table 21, respectively. It may be additionally provided. In this case, by providing the mark at the home position (fixed position) of the first and second scanning units, the mark can be detected immediately and the automatic document feeder such as SPF can be used. When the document cover is installed, it is possible to detect the open / closed state of the document cover even when the document is being conveyed. This makes it possible to detect the open / closed state of the document cover by providing marks at the home position and the document mount, respectively. The timing is advanced, the recovery process is accelerated, and it is possible to quickly prevent the document from being damaged.

Furthermore, if the lighting time of the lamp reflector assembly is determined based on the movement time of the first and second scanning units and the light source stabilization time during which the lamp reflector assembly stabilizes, it is possible to determine when the power source is activated. When the first and second scanning units are on standby in preparation for the next operation at the home position where the first and second scanning units conflict with the original placing table when the reading of the original is finished, the distance from the home position to the original placing table is By determining the lighting timing of the light source of the lamp reflector assembly based on the moving speed, the light amount of the lamp reflector assembly is stabilized, and the image can be read immediately after the movement of the optical system is completed.

[0074]

As described above, according to the present invention, the open / closed state of the document cover is detected by reading the mark on the document cover with the optical means before the document is conveyed to the reading position, and the document cover is opened. For example, by stopping the driving of the conveying means to stop the conveyance of the original, even if the original is accidentally instructed to start the original reading operation, the driving of the conveying means is stopped and the original is damaged. In addition, it is possible to prevent the risk of being unable to read the image data accurately, which may occur when the document is conveyed with the document cover floating. Moreover, the open / closed state of the document cover can be detected easily and at low cost without adding a new configuration.

In particular, by providing a plurality of marks within the maximum readable range that is not less than the maximum document width of the document cover, it is possible to reliably detect the marks by reading the plurality of marks and It is possible to reliably detect floating. In addition, the mark can be read regardless of whether or not the document is read, and even if the relative positions of the CCD and the document cover are misaligned, the change in the mark interval can be reliably recognized due to the wide interval between the marks, and the lift of the document cover can be detected. It can be done more accurately.

In particular, the marks are detected by the detecting means by the inner spacing between the peaks corresponding to the plurality of marks in the output waveform of the optical means, or the edge spacing. By detecting the mark by the detection means by the inner space, a relatively large floating outside the depth of field can be detected with the peak space deviated depending on the opening degree of the document cover, and the output waveform of the CCD is processed. It is possible to easily detect the floating of the document cover without the need.

Further, a mark is provided within the range of the maximum document width of the document cover, and the open / closed state of the document cover is detected by the detecting means before the document is conveyed or between pages of the document, thereby ensuring the detection of the mark. Therefore, it is possible to stably detect the floating of the document cover. In addition, the marks can be read before each document is conveyed, the change in the mark interval can be reliably recognized, and stable floating detection of the document cover can be performed.

In particular, by providing a mark at or near the home position of the optical means, the mark can be detected immediately, the opening / closing detection timing of the document cover can be advanced, and the recovery process can be carried out quickly. It can be prevented quickly.

By providing a marker at each of the home position of the optical means and the original reading portion which are contradictory to each other, the mark can be detected immediately at the home position of the optical means, while the original is being conveyed. Also, the open / close state of the document cover can be detected by the document reading unit, the recovery processing can be performed earlier by advancing the document cover open / close detection timing, and the document can be prevented from being damaged quickly.

Particularly, when the open state of the document cover is detected by the detecting means, the document conveying means on the upstream side of the document reading section is stopped and the document conveying means on the downstream side of the document reading section is continuously driven. By doing so, the reading of the original document remaining near the original reading unit where the trouble occurred is completed as it is, and the original document is ejected to the original document ejecting section by the original document conveying means on the downstream side of the original document reading section. By doing so, it is possible to reduce the burden on the operator.

In particular, by determining the lighting timing of the light source of the optical means based on the moving time of the optical means and the light source stabilization time during which the light source stabilizes, the distance and the moving speed from the home position to the document reading portion are determined. By determining the turn-on timing of the light source of the optical means, the light amount of the light source is stabilized and the image can be read immediately after the movement of the optical system is completed.

Further, when an optical means capable of reading a color image is applied, by using a color which is difficult for human eyes to recognize as the mark, the mark can be surely recognized by yellow of the color CCD. Even when the white document covers on the top and the back are opened, it is possible to eliminate the uncomfortable feeling given to the operator.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic internal configuration of an image forming apparatus including an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an internal configuration of an image reading apparatus.

FIG. 3 is a characteristic diagram showing changes in peak intervals of individual output waveforms corresponding to different marks depending on how the original cover is opened.

FIG. 4 is a schematic diagram showing a state in which two marks attached to a detection plate are imaged on a CCD when the document cover is opened and closed.

[Explanation of symbols]

10 Transport means 10a upstream side document conveying means 10b Downstream document transport means 12 Original cover 11a mark 2 Scanner unit (optical means) 21 Document Platen (Document Read Section) 27 CCD (detection means) A image reading device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 1/107 (72) Inventor Yoshiyori Hayashi 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) Inventor Mariko Arai 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Prefecture Sharp Corporation (72) Inventor Kazunori Miyamoto 22-22 Nagaike-cho, Abeno-ku, Osaka Prefecture Osaka Prefecture (72) Inventor Mikihiro Hayashi, 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Prefecture F-terms within Sharp Corporation (reference) 2H076 BA01 BA20 BA49 BA52 BA67 BA95 2H108 AA14 CA01 CB01 FA02 FA05 FA22 FA27 FA31 FC01 5C062 AA05 AB02 AB17 AB32 AB33 AC02 AC11 AC58 AE15 AF16 BA01 5C072 AA01 BA02 BA15 CA02 CA12 DA02 DA04 EA05 LA07 LA18 NA04 RA07 RA20 WA02 XA01

Claims (9)

[Claims] 1. A conveying means for conveying an original, an optical means for reading image information of the original conveyed by the conveying means, and an openable / closable cover for covering the original when the image information of the original is read by the optical means. In an image reading apparatus equipped with a document cover, a detection unit that detects the open / closed state of the document cover by reading a mark attached to the document cover with an optical unit, and the detection unit detects that the document cover is open. An image reading apparatus, characterized in that the image reading apparatus further comprises a conveyance stopping means for stopping the driving of the conveying means. 2. The image reading apparatus according to claim 1, wherein the document cover is provided with a plurality of marks that are not less than the maximum document width and are within the maximum readable range. . 3. The image reading apparatus according to claim 2, wherein the detection unit detects the mark by an inner interval between peaks or an edge interval corresponding to a plurality of marks in the output waveform of the optical unit. The image reading apparatus is characterized in that, when it is impossible to detect the mark, the mark is further detected by the inner distance between the peaks. 4. The image reading apparatus according to claim 1, wherein the document cover is provided with a mark within a range of the maximum document width or less, and the detection means is provided before the document is conveyed or between pages of the document. An image reading apparatus, which is adapted to detect an open / closed state of a document cover. 5. The image reading device according to claim 1, wherein the mark is provided at or near the home position of the optical unit. 6. The image reading apparatus according to claim 1, wherein when the home position of the optical unit and the document reading unit are provided at positions opposite to each other, a marker is provided at each of the home position and the document reading unit. An image reading apparatus characterized by being attached. 7. The image reading apparatus according to claim 1, wherein the conveying means includes original conveying means on the upstream side and the downstream side of the original reading section, and the detection means detects the open state of the original cover. At this time, the document feeding unit upstream of the document reading unit is stopped, and the document feeding unit downstream of the document reading unit is continuously driven. . 8. The image reading device according to claim 6, wherein the light source of the optical means for reading the image information of the document has a lighting timing based on the moving time of the optical means and the light source stabilization time during which the light source stabilizes. An image reading device characterized by being determined. 9. The image reading apparatus according to claim 1, wherein the mark is a color that is difficult for human eyes to recognize when an optical unit capable of reading a color image is applied. Characteristic image reading device.