JP3420883B2 - Double-sided document reader - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic double-sided document reading device, and more particularly to a document image reading device used in a copying machine, a printer, a facsimile device, a scanner, etc. The present invention relates to an improvement of an automatic double-sided document reading device that can read in a single document conveyance process.

[0002]

2. Description of the Related Art In a conventional image forming apparatus, scanner or the like, as a means for reading image information on each side in the process of separating and transporting double-sided originals stacked on an original tray one by one. , So-called ARDF (Auto Return Document Feeder) with one reading unit and document reversing unit
Is a known technique. In this ARDF,
After reading one side, the document is reversed and the back side is read, so that both sides are read. Further, a double-sided document reading apparatus of a type in which two reading optical systems are arranged along a document feeding path and both sides are simultaneously read while feeding a document is also well known (for example, Japanese Patent Laid-Open No. 4-23425).
No. 8).

[0003]

[Problems to be Solved by the Invention] However, the above A
In RDF, after separating the original on the original tray into one sheet and conveying it to a predetermined reading position for reading, the document is further inverted and conveyed again to the predetermined reading position and then the opposite surface. since double-sided reading in the procedure of discharges paper performs reading is performed, there is a problem that can not be quickly read throughput. In addition, since the conveyance path is complicated, there is a high possibility that the original may be damaged or damaged during the conveyance. Further, the double-sided document reading apparatus of the type that simultaneously reads both sides in the process of conveying a document using two optical systems has the following drawbacks.
That is, (1) "Since there is a double-sided original, there are more single-sided originals" because it is designed as a dedicated machine for reading double-sided originals
For such users, the machine configuration is large, complicated, and the cost is high. (2) When the above-mentioned user uses this type of double-sided original reading device to read a single-sided original, the reading optical system for reading the opposite side does not function at all, and there is a problem in that it is wasted. The present invention has been made in view of the above, and can be used for reading a single-sided original in a double-sided original reading apparatus that uses two optical systems to read images on both sides in the process of conveying a double-sided original. On the other hand, it can also be used for double-sided document reading,
Moreover, it is an object of the present invention to provide a double-sided image reading apparatus that does not cause the apparatus to become large and complicated when used for reading a single-sided original.

[0004]

[Means for Solving the Problems] To achieve the above object,
The present invention is installed on the main body scanner unit, body scan
Sheet raw with a pressure plate that covers the contact glass surface
An automatic draft feeding unit is provided, and while the sheet original is automatically fed and moved by the sheet original feeding unit onto the reading unit on the main body scanner unit, an image is read by the first optical reading unit in the main body scanner unit. In the original reading device
Set the exit side of the sheet automatic document feeder to
Installed on the pressure plate side that covers the contact glass surface of the body scanner section.
On the pressure plate at the exit side of the sheet discharge unit of the automatic sheet document feeder
A sheet original feeding / reading section is detachably arranged, and the sheet original feeding / reading section includes a second optical reading unit for reading an image on the opposite side of the sheet original , and the sheet original automatic reading unit.
Receive the sheet originals that are ejected from the exit of the paper ejection unit of the feeding unit.
Put characterized in that a document conveying means for conveying to said second optical reading unit. Further, the present invention is
A power supply and image processing / control means are further added to the sheet document feeding and reading section so that the sheet document feeding and reading section can be used as a single-sided sheet document reading device.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the embodiments shown in the drawings. FIG. 1 is an overall view showing the basic configuration of an example of one embodiment of the double-sided document reading apparatus of the present invention. This double-sided document reading device includes a main body scanner unit 1, a sheet original automatic feeding unit 2 mounted on the main body scanner unit 1,
A sheet document feeding / reading unit 3 is configured to be detachable from the sheet document automatic feeding unit 2. FIG. 2 is a diagram showing a state in which the sheet original feeding and reading unit 3 and the control board 5 are removed from the double-sided original reading apparatus of FIG. Show. FIG. 3 is a diagram in which the removed sheet document feeding / reading unit 3 and the control board 5 are attached to a power source unit 7 having a power source 6, and a configuration example in which sheet documents on one side are manually fed and read one by one. Is. Next, the double-sided document reading device will be described in more detail. The main body scanner unit 1 is provided with a first optical reading unit 4 (4A), a control board 5, a power supply unit (not shown), etc. inside the housing, and a contact glass surface 8 and a sheet original reading on the upper surface of the housing. A section (slit glass) 9 and a document guide 10 are provided. The first optical reading unit 4A provided in the main body scanner unit 1 is located at the position shown in FIG. 1 (the sheet document reading unit 9 when reading the document conveyed by the sheet document automatic feeding means 2).
(Directly below position). When reading a BOOK document or a document that cannot be used by the automatic feeding means 2, the sheet original feeding means 2 is rotated around a hinge (not shown) to open the contact glass surface 8.
A document is placed on the contact glass surface 8 along the document guide 10, and the first optical reading unit 4A is reciprocally moved along a guide rail, a guide rod or the like (not shown) to perform reading. The control board 5 controls a series of reading operations and performs image processing on the read image data.

The first optical reading unit 4A comprises at least one illumination light source 11, several mirrors 12, a condenser lens 13, and a photoelectric conversion means 14 (CCD or the like). In the example shown in this figure, the optical reading unit 4 is drawn as a monochrome reduction optical system, but it may be a unity magnification optical system or a color image using means such as a 3-line CCD or a light source switching. It may be a reading optical system. Further, it may be a color equal-magnification optical system. The sheet document automatic feeding means 2 is provided with a document tray 1 projecting to the outside.
5, a calling roller 16 for taking out the originals on the original tray 15 one by one, a separating means 17 for preventing the multi-feeding of the taken-out originals, a guide for guiding the originals to the reading position, and transferring the originals in the discharging direction. Consists of a transport roller 18, a paper discharge roller 19 for discharging a document from the feeding unit 2, a platen 20 for appropriately pressing the document on the sheet document reading unit 9, and the like, and detects the passage of the fed document. Document sensor 21, feed sensor 22, reading start sensor 23,
The paper discharge sensor 24 and the like are arranged at predetermined positions.

When documents are stacked on the document tray 15,
The calling roller 16 takes out the lowermost original and conveys it. Even if several originals are sent out at the same time, they are separated into one by the separating means 17 and conveyed.
As the separating means, a method called FRR, a method using misaligned rollers, a method using a friction belt, a method using a friction pad, or the like can be adopted. The separated original is detected by the feed sensor 22 and is conveyed at a predetermined speed along the guide plate toward the reading position by the conveying roller 18. When the reading start sensor 23 detects the leading edge of the document, the reading is started by conveying the document to the reading position, and while the document is conveyed at a constant speed, the optical reading unit 4 performs reading for a predetermined length. Be done. The document that has been read is conveyed by the roller 18
The sheet is conveyed toward the sheet discharge section. The document sensor 21 detects that there is no more document, and the operation is stopped after the last document is ejected. The discharge sensor 24 detects the discharge of the document. Incidentally, driving such as feeding and feeding is performed by a motor (not shown).

Next, the sheet original feeding / reading section 3 has a second optical reading unit 4 (4B) inside the casing thereof, and the second optical reading unit 4B is the first inside the scanner section of the main body. The same components as those of the optical reading unit 4A are configured in the same arrangement. Further, in addition to the second optical reading unit 4B, a conveyance roller 25 (conveyance means) that is rotationally driven by a drive motor (not shown), a paper discharge roller 26.
It has a (conveying means), a paper feed sensor 27, and a platen 20. The second optical reading unit 4B is installed upside down with respect to the first optical reading unit 4A. The document discharged to the outside of the feeding unit 2 by the discharge roller 19 of the sheet document automatic feeding unit 2 enters the second optical reading unit 4B from the guide plate entrance of the second optical reading unit 4B. When the paper feed sensor 27 detects the leading edge of the original, the feeding roller 25 and the paper discharging roller 26 are driven to start reading at the time when the feeding roller 25 and the paper discharging roller 26 feed a predetermined length.
The read document is discharged by the discharge roller 26 to the discharge tray 2
8 is discharged. According to the exemplary embodiment of FIG. 1, the first optical reading unit 4A of the main body scanner unit 1 is thus configured.
And the second optical reading unit B mounted on the sheet document automatic feeding means 2 can read both the front and back sides of a double-sided document during one conveyance process. It should be noted that the second optical reading unit 4B includes the sheet document automatic feeding means 2
It is positioned on the pressure plate portion 29 and is detachably fixed by a predetermined fixing means.

Next, the second optical reading unit 4 shown in FIG.
B (sheet original feeding / reading section 3) and the corresponding control board 5 are removed, and the main body scanner section 1 is shown in FIG.
Then, only the sheet document automatic feeding means 2 is provided, and an image reading apparatus with an automatic document feeding apparatus for a single-sided document is provided. For a user who uses only one-sided originals, it is advantageous to use such a form in terms of space saving and handling. In this embodiment, the second optical reading unit 4B (sheet original feeding / reading section 3) is detachably arranged at the exit of the sheet original automatic feeding means 2, so that only the single-sided original is read as shown in FIG. second optical reading Yoo as
The knit 4B (sheet original feeding / reading section 3) may be removed before use, and the second optical reading unit 4B (sheet original feeding / reading section 3) may be mounted when reading a double-sided original. That is, a single-sided original reading device can be a double-sided original reading device simply by adding one unit, and thus a low-priced double-sided original reading device can be realized with a simple configuration. Further, when the second optical reading unit 3 removed from the sheet document automatic feeding means 2 is assembled with the control board 5 in the power supply unit 7 having the power source 6, a sheet document reading device as shown in FIG. 3 is obtained. Become. By using the second optical reading unit 4B removed in this way independently, rather than leaving it alone, each user can use the single-sided original without sacrificing the functions. Can be effectively utilized.

[0010]

According to the image reading apparatus of the present invention , the second sheet is formed on the pressure plate at the exit side of the document discharge section of the sheet document automatic feeding means.
Since the optical reading unit of is detachably arranged,
When only a single-sided original is to be read, the sheet original feeding / reading section 3 provided with the second optical reading unit as shown in FIG. 2 may be removed to use only the main body scanner section 1 and the sheet original automatic feeding means 2. When reading a double-sided original, the second optical reading unit (sheet original feeding / reading section 3) may be attached to form the configuration shown in FIG. That is, since the double-sided original reading device can be obtained by simply adding one unit 4B on the single-sided original reading device, it is possible to provide an inexpensive double-sided original reading device with a simple configuration.

In the image reading apparatus of the present invention ,
Even when the image reading apparatus is used as a single-sided sheet original reading apparatus as shown in FIG. 2, by adding a power source, image processing, and control means to the removed second optical reading unit (sheet original feeding / reading section 3). Since it can be used as a single-sided sheet original reading device, the second optical reading unit is not left, and waste can be eliminated.

[Brief description of drawings]

FIG. 1 is an overall view of a double-sided automatic document reading apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state in which a second optical reading unit is removed.

FIG. 3 is a configuration diagram of a reading device using a removed second optical reading unit.

[Explanation of symbols]

1 Main Body Scanner Section 2 Sheet Original Automatic Feeding Means 3 Sheet Original Conveyance Reading Section 4 (4A, 4B) Optical Reading Unit 5 Control Board 6 Power Supply 7 Power Supply Unit 8 Contact Glass Surface 9 Sheet Original Reading Section (Slit Glass) 10 Document Guide 11 Illumination Light Source 12 Mirror 13 Condenser Lens 14 Photoelectric Converter 14 (CCD, etc.) 15 Document Tray 16 Calling Roller 17 Separator 18 Conveying Roller 19 Paper Ejecting Roller 20 Platen 21 Document Sensor 22 Feed Sensor 23 Reading Start Sensor 24 Paper ejection sensor 29 Pressure plate

Claims (2)

(57) [Claims] 1. A main body scanner installed on the main body scanner section ,
A seat with a pressure plate that covers the contact glass surface of the canner.
A sheet original is automatically fed by the first original reading unit in the main body scanner section while feeding and moving the sheet original onto the reading section on the main body scanner section. In the document reading device for performing the above-mentioned document reading,
Installed on the pressure plate side that covers the contact glass surface of the body scanner section.
On the pressure plate at the exit side of the sheet discharge unit of the automatic sheet document feeder
To, to place the sheet original conveying reading unit detachably, the sheet document feeding and reading unit, a second optical reading unit for reading an image on the opposite surface of the sheet original, the sheet original
Sheet originals ejected from the exit of the paper exit of the automatic document feeder
A double-sided document reading device comprising: a document feeding unit that receives a document and conveys it to the second optical reading unit. 2. The double-sided document reading device according to claim 1.
The sheet original feeding / reading unit, a power source, and image processing /
A double-sided document reading device, further comprising control means so that it can be used as a single-sided sheet document reading device.