JP3736362B2 - Document reader - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a document reading apparatus for inputting a document image in a copying machine, a facsimile, or the like, and more specifically, a so-called sheet-through method that reads a document image while conveying the document, and a state where the document is fixed. The present invention relates to an improvement of a document reading apparatus capable of performing both a so-called optical system moving method for reading a document image.
[0002]
[Prior art]
In a copying machine or a facsimile, a document reading device for inputting a document image is indispensable for the function of copying or transmitting a document. This type of document reading apparatus has two types of methods for scanning a document image. One is a so-called optical system moving method in which an original is temporarily stopped on a platen, and scanning is performed while moving a scanning member mounted with an illumination lamp and a mirror under the platen. This is a so-called sheet-through method in which the scanning member is stationary under the platen and the image is captured while the document is conveyed on the platen.
[0003]
The former optical system moving method can input not only ordinary originals such as paper, but also so-called book originals such as books and magazines, but it is necessary to keep the original on the platen, so that the unit time The number of input sheets per hit cannot be set large, resulting in poor productivity. On the other hand, the latter sheet-through method can input multiple originals quickly and continuously, and is excellent in productivity, but it cannot input cardboard or book originals, so the types of originals that can be handled are limited. is there.
[0004]
Therefore, in recent years, image reading apparatuses capable of inputting document images by either the optical system moving method or the sheet-through method have appeared, mainly having both functions of a copying machine and a facsimile. It is installed in the MFP. The image reading apparatus includes a first platen used for reading a document by a sheet-through method, an automatic document conveying means for continuously feeding a plurality of documents to the first platen, and a first platen. A second platen that is provided adjacently and used when reading a book document; and a scanning member that is movably provided along the lower surface side of the first platen and the second platen. In the case of using the through method, the scanning member is stopped immediately below the first platen, while reading the image of the document moving in the sub-scanning direction while keeping a close contact with the first platen or with a slight gap between the first platen, In the case of the optical system moving method, the scanning member is moved in the sub-scanning direction along the second platen, and an image of the original set on the second platen is read. It is configured. As a result, in the case of normal originals such as paper, a plurality of originals can be quickly read by the sheet-through method, and even in the case of special originals such as book originals, the second platen can be used for copying. And facsimile transmission.
[0005]
[Problems to be solved by the invention]
In such a document reading apparatus, a partition member is provided between the first platen and the second platen, and the partition member is provided with an inclined surface on the first platen side. This inclined surface lifts the leading edge of the conveyed document so as to be in close contact with the first platen, and assists the automatic document conveying means to send the document to the discharge tray. On the other hand, since all the originals passing through the first platen by the sheet-through method are conveyed in sliding contact with the inclined surface of the partition member, eraser scraps, dust, etc. adhering to the original are separated from the inclined surface and the first surface. Easily collects at the boundary with the platen [0006]
On the other hand, in order to reduce the initial movement amount of the scanning member so that the reading job can be started smoothly, the reading standby position of the scanning member before the start of the reading job is the end of the second platen on the partition member side. The scanning member is stopped in the vicinity of the partition member.
[0007]
For this reason, when replacing the internal parts or cleaning the optical system parts, if the partition member is removed together with the second platen, the foreign matter accumulated at the bottom of the inclined surface of the partition member falls to the inside, and the partition There was a problem that it adhered to the mirror, illumination lamp, etc. of the scanning member that had stopped below the member. If a document image is read with foreign matter adhering to a mirror or an illumination lamp, black streaks occur in the input image along the sub-scanning direction, and the image quality is significantly degraded. .
[0008]
The present invention has been made in view of such problems, and its object is to remove a partition member provided between the first platen and the second platen and replace internal components or optical components. Provided is a document reading apparatus capable of preventing troubles that foreign matters adhering to the partition member adhere to the scanning member when performing a cleaning operation and preventing deterioration in image quality due to the adhesion. There is to do.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, an original reading apparatus of the present invention includes a first platen used for reading an original by a sheet through method, and an automatic automatic feeding of a plurality of originals to the first platen. A document conveying means, a second platen provided adjacent to the first platen and used for reading a book document, and a partition member provided between the first platen and the second platen The first platen and the second platen are movably provided along the lower surface side of the first platen, and when the original image is read using the first platen, the first platen is fixed immediately below the first platen, while the second platen is fixed. A scanning member that scans the document image while moving along the second platen when the document image is read using the platen, and the partition member is attached to the first platen. When the maintenance is performed with the partition member and the second platen removed, the scanning member is moved to a retracted position provided separately from the reading standby position. .
[0010]
When the main power source of the original reading apparatus is turned on, both the reading of the original image by the sheet-through method using the first platen and the reading of the original image by the optical system moving method using the second platen can be quickly handled. In order to obtain, it is preferable that the scanning member on which the illumination lamp and the mirror are mounted is set in the vicinity of the partition member located between the first platen and the second platen. In this case, maintenance work is performed with the scanning member set at the reading standby position, and when the partition member is removed, the upper side of the scanning member is opened, so the eraser attached to the partition member As a result, debris, dust, and the like fall on the scanning member located below.
[0011]
However, as in the present invention, when the partition member and the second platen are removed and maintenance work is performed, if the scanning member is configured to be reset to a retracted position provided separately from the reading standby position, the scanning member It is possible to remove the partition member while keeping it away from the partition member or in a space covered in the upper part, and to prevent foreign matter from adhering to optical components such as illumination lamps and mirrors. It becomes possible to prevent.
[0012]
Here, the retracted position may be directly below the first platen, for example, if the first platen is not removed during the maintenance work. Since the gap between the platen and the scanning member is extremely small (for example, about 2 mm), if the scanning member is retracted to the lower side of the first platen, the foreign matter dropped from the partition member does not fall on the scanning member, It becomes possible to prevent contamination of an illumination lamp or the like. In other words, it is preferable to set a space where the scanning member can be shielded from the upper space as the retracted position also during maintenance work of the optical system parts.
[0013]
It is also effective to set the scanning member at a position away from the partition member instead of shielding the scanning member from the partition member in the retracted position. In other words, the retreat position is set immediately below the end of the second platen opposite to the partition member, and the maintenance position is set so as to cross from below the second platen to the retreat position from the reading standby position. May be. If the retreat position is set in this way, the foreign matter dropped from the partition member during the maintenance work does not adhere to the scanning member.
[0014]
On the other hand, it is the timing for setting the scanning member from the reading standby position to the retracted position, but this timing may be configured so that the user can freely input a movement command to the retracted position, or depending on some operation It may be configured to be automatically set without the user being aware of it. Examples of the latter automatically set are when the main power is turned off, when an abnormal operation occurs during the reading operation of the document, etc., and in these cases, there is a high possibility that maintenance work will be performed subsequently. Therefore, the scanning member is automatically set from the reading standby position to the retracted position. Alternatively, the removal work of the partition member and the second platen may be detected by an optical sensor or the like, and the scanning member may be set at the retracted position based on the detection result.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the document reading apparatus of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a perspective view showing an external appearance of a digital copying machine 1 to which a document reading apparatus according to the present invention is attached. The copying machine 1 includes an image input unit (IIT) 2 as an image reading device that reads an original image and converts it into an image signal, and a copy image on a recording sheet based on an image signal sent from the image input unit 2. And an image output unit (IOT) 3 for forming the.
[0016]
The image input unit 2 includes an automatic document feeder (ADF) 4, and FIG. 1 shows a state in which the ADF 4 is lifted. The image input unit 2 includes a first platen 20 for reading a document image while using the ADF 4, and a second platen 21 for manually reading a document image without using the ADF 4, and the latter second platen 21. Is formed so as to be able to set the entire surface of the original, whereas the former first platen 20 is elongated along the edge of the second platen 21 in the main scanning direction (the depth direction of the copying machine). .
[0017]
FIG. 2 is a schematic diagram showing the configuration of the image input unit 2, and shows a state where the ADF 4 is closed on the platens 20 and 21. Inside the housing 22 of the image input unit 2, an illumination lamp 23 that illuminates the document 5 through the first or second platen 20, 21, and reflected light of the document by the illumination lamp 23 along the lower surface of the platen 21. The first mirror 24 that reflects in the direction, the second and third mirrors 25 and 26 that fold the reflected light from the first mirror 24 in parallel, and the reflected light from the third mirror 26 is imaged by the lens 27. The reflected light from the document 5 is input to the CCD sensor 28 through a plurality of mirrors so that the document image is converted into an electrical image signal through the light. It has become. The illumination lamp 23 and the first mirror 24 are mounted on a first carriage 30 as a scanning member movable along the lower surfaces of the first and second platens 20 and 21, while the second and third mirrors 25 and 26 are mounted. Is mounted on the second carriage 31 as a roof mirror, and the second carriage 31 is configured to move in the same direction at half speed in accordance with the movement of the first carriage 30. When the original image is read using the second platen 21, the first carriage 30 moves below the platen 21 to scan the original 5, while the first platen 20 is used. When reading a document image, the first carriage 30 is fixed under the platen 20 and scans the document 5 passing over the first platen 20. That is, in the image input unit 2, reading of books and the like that cannot be handled by the ADF 4 is performed by moving the optical system without moving the original, and the original that can be handled by the ADF 4 is not moved by moving the optical system. This is done by moving the document.
[0018]
On the other hand, the ADF 4 includes a document tray 40 on which the document 5 is set, a document transport unit 41 that feeds the document 5 drawn one by one from the document tray 40 to the first platen 20, and the first platen 20. A document discharge tray 42 that discharges the input document 5 that has passed through is provided, covers the first platen 20 and the second platen 21, and can be opened and closed with respect to the platens 20 and 21. Is provided.
[0019]
The document transport unit 41 includes a pickup roll 43 that pulls the document 5 stacked on the document tray 40 into the document transport unit 41, and a sheet feed for feeding a plurality of documents 5 one by one. Skew correction is performed by temporarily locking the roll 44, the retard roll 45 disposed opposite to the paper feed roll 44 to prevent double feeding of the original 5, and the original 5 fed from the original tray 40. A registration roll 46 that is fed to the first platen 20 at a predetermined timing after being performed, a platen roll 47 that conveys the document 5 on the first platen 20, and the document 5 that has passed through the first platen 20 is discharged to the discharge tray 42. And an exit roll 48.
[0020]
Further, a paper feed sensor 50 for detecting the fed document 5 is provided immediately after the paper feed roll 44, and a registration sensor 51 for detecting the document 5 passing through the registration roll 46 is provided immediately before the registration roll 46. Immediately before the roll 48, an exit sensor 52 for detecting whether or not the document 5 is discharged to the document discharge tray 42 is provided, and each roll of the document transport unit 41 described above is synchronized with detection signals of these sensors. It is driven at a predetermined timing.
[0021]
Further, a document detection sensor (not shown) for detecting the document 5 set on the document tray 40 is provided at the entrance of the document transport unit 41, and the output of the document detection sensor is checked by checking the output of the document detection sensor. It is possible to determine whether or not to read an original image by a sheet-through method using the first platen 20 or to read an original image by an optical system moving method using the second platen 21.
[0022]
FIG. 3 is an enlarged view showing the vicinity of the connecting portion between the first platen 20 and the second platen 21. A partition member 6 is provided between the first platen 20 and the second platen 21 along the main scanning direction, and the first platen 20 and the second platen 21 are separated by the partition member 6. In order to make it easy for the front end of the document 5 pressed against the first platen 20 by the platen roll 47 to enter the exit roll 48, an inclined surface 60 is formed on the first platen 20 side of the partition member 6. The document 5 is pulled away from the first platen 20 when the tip of the document 5 is in sliding contact with the inclined surface 60. Further, a lead registration surface 61 for positioning a book document set on the second platen 21 is formed on the second platen 21 side of the partition member 6. The partition member 6 is integrated with the second platen 21, and when performing maintenance work such as cleaning or replacement of the components of the optical system, the partition plate 6 is removed together with the image input unit. The upper part of the two housings 22 is opened.
[0023]
The stop positions of the first and second carriages 30 and 31 shown in FIG. 3 are in a state in which the main power of the copying machine 1 is turned on, that is, the image input unit 2 is in a document image reading standby state. The stop positions (read standby positions) of the first and second carriages 30 and 31 at a certain time are shown. This reading standby position corresponds to the reading start position of the book document using the second platen 21 and is directly below the end of the second platen 21 on the partition member 6 side. Therefore, when a book document is set on the second platen 21 and the copy start button is pressed, the first carriage 30 starts from this reading standby position and moves to the right along the lower surface of the second platen 21. As a result, the reading of the image of the book document is started immediately. On the other hand, when the document 5 is set on the document tray 40 and the copy start button is pressed, the first carriage 30 moves immediately below the first platen 20 and is in close contact with the first platen 20 as shown in FIG. Thus, the image of the document 5 conveyed is read. Note that the alternate long and short dash line in FIG.
[0024]
However, when the original image is read by the sheet-through method using the ADF in this way, the original 5 is separated from the first platen 20 by slidingly contacting the inclined surface 60 of the partition member 6, so that it adheres to the original 5. The eraser scraps and dust that have been removed are wiped off by the partition member 6 and tend to accumulate at the boundary between the partition member 6 and the first platen 20, as shown in FIG. For this reason, when the optical system parts are cleaned or replaced, as shown in FIG. 6, if the partition member 6 is removed together with the second platen 21 with the first carriage 30 set to the reading standby position, Foreign matter such as dust accumulated at the boundary between the partition member 6 and the first platen 20 falls on the first carriage 30 located immediately below and adheres to the illumination lamp 23, the mirror 24, and the like.
[0025]
Therefore, in the image input unit 2 of this embodiment, in order to avoid the occurrence of such trouble, when performing maintenance work such as cleaning or replacement of the optical system parts, the first reading standby position is set to the first reading standby position. The carriage 30 is configured to be reset to a retracted position where foreign matter is difficult to adhere. As a first example of the retracted position, if the first platen 20 is provided so as not to be detachable, the position immediately below the first platen 20 is effective as shown in FIG. The gap between the first platen 20 and the first carriage 30 is as extremely small as about 2 mm. If the first carriage 30 can be completely accommodated under the first platen 20, the first platen 20 can remove foreign matters such as dust. It will shield you. Further, the amount of movement of the first carriage 30 when resetting from the reading standby position is also small.
[0026]
Further, if the first platen 20 is to be removed during maintenance work, as shown in FIG. 8, the retracted position covered not by the first platen 20 but by the housing of the image input unit 2 is provided. It is preferable to reset the first carriage 30 from the reading standby position to the retracted position below the housing 22. According to this configuration, even if the first platen 20 is removed during maintenance work of the custom optical system parts, the first carriage 30 set at the retracted position is covered with the housing 22 at the top. Even if foreign matter such as dust attached to one platen 20 falls into the housing 22 of the image input unit 2, it is possible to avoid the trouble that the foreign matter adheres to the illumination lamp 23 and various mirrors 24, 25, and 26. Can do.
[0027]
Further, the retracted position of the first carriage 30 is not necessarily set on the first platen 20 side with respect to the reading standby position, and the partition member 6 on the opposite side of the second platen 21, that is, the second platen 21. It may be set directly below the end on the opposite side. In this way, the first carriage 30 is positioned on the opposite side of the partition member with the second platen interposed therebetween, so that foreign matter such as dust is removed from the partition member 6 during maintenance work of the optical system parts. Even if it falls, it does not fall on the first carriage 30. In any case, it is important that the first carriage 30 on which the illumination lamp 23 and the mirror 24 are mounted is not located near the boundary between the first platen 20 and the partition member 6 during maintenance work.
[0028]
It is desirable that the first carriage 30 is always set to the retracted position during the maintenance work so that the movement from the reading standby position to the retracted position is automatically performed. In the maintenance work performed with the second platen 21 removed, the main power source of the copying machine 1, that is, the image input unit 2 is usually turned off before the work starts. 2, when the main power supply of the copying machine 1 is turned off, the first carriage 30 set in the reading standby position is automatically reset to the above-described retracted position. Specifically, when the main power switch of the copying machine 1 is turned off, the image input unit 2 is turned off with a delay, and it is determined that the copying machine main power is turned off. The first carriage 30 is reset from the reading standby position to the retracted position, and the power of the image input unit 2 is turned off after the resetting operation is completed. According to such a configuration, when the second platen 21 and the partition member 6 are removed after the power of the image input unit 2 is turned off, the first carriage 30 is always set to the retracted position, and the removal is performed. It is possible to prevent troubles that foreign matters adhere to the illumination lamp 23 and the mirror 24 during the work.
[0029]
On the other hand, since it is also assumed that the second platen 21 and the partition member 6 are removed without turning off the main power supply, in the case where maintenance work of the optical system parts is expected, for example, the first Alternatively, when an abnormal operation or failure occurs during the reading operation of the document 5 using the second platens 20 and 21, the first carriage 30 is set to the retracted position without returning to the reading standby position. Is also effective. In this case, the image input unit 2 may be configured to notify the user via the user interface such as the liquid crystal display of the copying machine 1 at the same time as setting the first carriage 30 to the retracted position.
[0030]
Further, it is possible to automatically detect the removal work of the second platen 21 itself, and set the first carriage 30 to the retracted position based on the result. For example, a sensor for detecting attachment / detachment of a pressing member (not shown) for fixing the second platen 21 to the housing 22 of the image input unit 2 is provided, and the first carriage 30 is based on the detection result of the sensor. Is set to the retracted position. The sensor may be a contact type sensor that is turned on / off in response to the lifting of the pressing member, or a reflective photosensor that is turned on / off by a change in the amount of reflected light from the pressing member. According to such a configuration, it is possible to directly grasp that the removal work of the second platen 21 and the partition member 6 is performed, and as a result, the first carriage 30 can be reset to the retracted position. It is possible to reliably prevent foreign matter from falling on the lamp 23 and the mirror 24.
[0031]
The first carriage is intentionally set from the reading standby position to the retracted position by a direct instruction from the user or a service engineer who performs maintenance work, for example, by inputting a predetermined code via the user interface. Of course, it may be.
[0032]
【The invention's effect】
As described above, according to the document reading apparatus of the present invention, when performing maintenance work with the partition member and the second platen removed, the scanning member is set at a retracted position provided separately from the reading standby position. In such a case, the scanning member can be removed from the partition member, or the partition member can be removed in a state where the scanning member is accommodated in the space covered above, so that it does not adhere to the partition member during the maintenance operation. It is possible to prevent troubles such as dust and other foreign matter adhering to the scanning member, and it is possible to prevent deterioration in quality of the read image due to such adhesion.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a copying machine equipped with a document reading apparatus of the present invention.
FIG. 2 is a front sectional view showing a schematic configuration of an embodiment of an image input unit to which the present invention is applied.
FIG. 3 is an enlarged cross-sectional view illustrating the periphery of a partition member of the image input unit according to the embodiment.
FIG. 4 is an enlarged cross-sectional view illustrating a state when reading a document by a sheet through method using a first platen.
FIG. 5 is a diagram illustrating a state in which foreign matter accumulates at a boundary portion between a first platen and a partition member.
FIG. 6 is a diagram illustrating a problem that occurs when a second platen and a partition member are removed.
FIG. 7 is an enlarged cross-sectional view illustrating an example of a retracted position of the first carriage according to the embodiment.
FIG. 8 is an enlarged cross-sectional view illustrating another example of the retracted position of the first carriage according to the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 4 ... ADF (automatic document conveying means), 5 ... Document, 6 ... Partition member, 20 ... First platen, 21 ... Second platen, 30 ... First carriage (scanning member)

Claims (6)

A first platen used for reading a document by the sheet-through method, an automatic document conveying means for continuously feeding a plurality of documents to the first platen, and a first platen adjacent to the first platen. And a second platen used for reading a book document, a partition member provided between the first platen and the second platen, and movable along the lower surfaces of the first platen and the second platen. When the original image is read using the first platen, it is fixed immediately below the first platen, while when the original image is read using the second platen, the second platen is fixed. A scanning member that scans a document image while moving along
The partition member is provided detachably with respect to the first platen, and when the partition member and the second platen are removed for maintenance work, the scanning member moves to a retracted position provided separately from the reading standby position. An original reading apparatus characterized by being set. 2. The document reading apparatus according to claim 1, wherein the retracted position is directly below the first platen. 2. The document reading apparatus according to claim 1, wherein the retracted position is directly below an end of the second platen opposite to the partition member. 2. The document reading apparatus according to claim 1, wherein the scanning member is set from the reading standby position to the retracted position in conjunction with the removal work of the partition member. 2. The document reading apparatus according to claim 1, wherein when the main power is turned off, the scanning member is set from the reading standby position to the retracted position. 2. The document reading apparatus according to claim 1, wherein the scanning member is set at the retracted position when an abnormal operation or a failure occurs during the document reading operation.

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