JPH01294137A - Original feeding control system for image reader - Google Patents

Abstract

PURPOSE:To aim at the promotion of high speed for an image data read rate by feeding an original, performing a data readout subsequently, up to a spot just before a data read starting position in advance. CONSTITUTION:An automatic original feeding unit 3 is constituted of conveyor rollers 34, 35, 36 conveying an original 6 at constant speed, a sponge roller 37 pressing down any flattering of the original 6 in an original reading part, original passing detection sensor 39, 40, 43 and a control substrate 35 controlling each element. Paper feed-of the original 6 is started, and a fact that the original 6 has been fed is detected by the original passing detection sensor 39, while at this time, a counter gate is turned on, conveying the original 6 as far as a distance commensulate to an original stop position setting value, and the paper feeding of the original 6 is stopped at a time when a counter comes to zero. Thus, the original 6 is fed to the extent of an original stopping position just before a data read starting position in advance.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a document feeding control method for an image reading device, and more particularly, to a control method of this type that reduces the time required for document feeding. Regarding.

[Conventional technology]

Product concepts required for image reading devices include high image quality, high resolution, and ease of use, but one of the important product concepts is high image data reading speed.

[Problem to be solved by the invention]

Therefore, in order to increase the image data reading speed,
For example, as shown in Japanese Patent Publication No. 62-33790, in a method of reading image data by moving an optical system with respect to a stationary document, even if an attempt is made to increase the moving speed of the optical system, The influence of inertia is large, and the speed increase has to reach its limit.

In addition, in order to increase the image data reading speed, for example, as shown in Japanese Utility Model Publication No. 62-22518, a large number of sheet-like originals set in a document tray are separated one by one and a static optical system is used to separate them one by one. Read continuously. In the so-called automatic document reading method, as described above, a large number of sheet-like originals set on a document tray are separated one by one in sequence, and the sheet-like originals that have been separated at high speed as described above are It is also necessary to transport the original to the reading start position at high speed, but it is technically extremely difficult to speed up the separation of the original that is performed prior to the high-speed transport of the sheet-like original, so in order to solve this problem, Various researches and
Development is underway.

An object of the present invention is to use a so-called automatic document reading method in which a large number of sheet documents set in a document tray are separated one by one and read continuously by a static optical system.
It is possible to create a virtual image data reading speed that can be achieved as a result without adopting the technically extremely difficult method of increasing the speed of document separation performed prior to high-speed conveyance of the sheet-like document. An object of the present invention is to provide a document feeding control system for an image reading device that can perform the following steps.

[Means to solve the problem]

The purpose is to read a large number of original sheets in succession in an image reading method in which a large number of sheet originals set in a document tray are separated one by one and read continuously by a static optical system. In preparation for reading the original image data, during the waiting time for the data to be exchanged between the previously sent original reading data and the host, in parallel, the original to be read next is read in advance up to just before the data reading start position. This is achieved by sending

[Effect]

By the way, one document has a resolution of 400dpi x 400d.
When reading with Pi, for example, an A4 size document has a data amount of about 16 Mbit, and when transmitted at a clock rate of 8 MHz, it takes about 2 seconds to transmit the data. Therefore, this two seconds is a waiting time for data exchange, and during this time the scanner cannot read the next document. Therefore, when reading a large number of sheet-like originals in succession, in preparation for reading the original image data, the previously sent original scanned data and the waiting time for data exchange with the host are read in parallel. If the original for which data reading is to be performed in the first stage is fed in advance to just before the data reading start position, the original feeding process will be performed within the waiting time for data exchange, which will allow high-speed processing of sheet-type originals. This does not require the use of the technically extremely difficult method of speeding up document separation prior to transport.

As a result, it can be assumed that the image data reading speed is increased.

〔Example〕

Hereinafter, the present invention will be explained based on one embodiment of the drawings. FIG. 1 is an explanatory diagram of the internal structure of the automatic document feeding unit 3, FIG. 2 is a control circuit diagram of the document feeding system, and FIG. A perspective view showing the overall configuration of the image reading device, FIGS. 4 to 6 are explanatory diagrams of the operation in the manual document reading mode on the document platen glass 14, and FIG. 7 is an operation in the document reading mode by the automatic document feeding unit 3. It is an explanatory diagram.

As shown in FIG. 3, the overall configuration of the image reading device is roughly comprised of a main body 1 that includes an optical system, an image data reading circuit, etc., a document cover 2 that holds a document 6, and a document tray 4 that is placed on a document tray 4. An automatic document feeding unit 3 that automatically separates and transports set documents 6 one by one, function selection, and mode settings.

It is composed of an operation panel 5 that performs display.

In FIG. 4, which is an explanatory diagram of the operation in the manual document reading mode on the document table glass 14, the manual document reading section is a reading sensor 7a fixed to the main body 1.

A lens unit 7 composed of a lens 7b, and a fluorescent lamp 8° mirror 9 that moves left and right on a rail (not shown).
．． FL unit 10 composed of heater 15;
It is composed of a mirror unit 13 in which mirrors 11 and 12 are arranged, and a document table glass 14. and,
In Figures 5 and 6.

A motor 16 which is a driving source. Gear (1)17. Gear (2)
18. Wire 19. Home position sensors 2o and 21. which serve as positioning references for the wire pulley 24. FL
Limit switches 22 and 23, which are runaway prevention sensors for the unit 10. A tension spring 25 is shown which applies tension to the wire 19 at all times.

In FIG. 7, which is an explanatory diagram of the operation of the automatic document feeding unit 3 in the document reading mode, and furthermore, in FIG. In order to separate sheet-like originals one by one and read them continuously using a static optical system, a motor 30 serving as a driving source rotates a pickup roller 31 via a gear (not shown), and a document detection sensor 42 is activated. The passed originals 6 are separated one by one by a separator 32.

In FIG. 1, reference numeral 38 denotes a document double feed prevention sensor, which stops the paper feeding system when a plurality of documents 6 are about to be fed in duplicate.

Further, in FIG. 1, the automatic document feeding unit 3 includes, in addition to the above-mentioned components, a transport roller (1) 34 that transports the document 6 at a constant speed. (2)35. (3) 36 and a sponge roller 37 that suppresses the flap of the original 6 in the original reading section
and document passage detection sensors (1) 39, (2) 40. (3
) 43, a white reference 41 for checking the amount of light from a fluorescent lamp, and a control board 45 for controlling each part.

By the way, as is clear from the above description, the image reading apparatus shown in the illustrated embodiment has a manual document reading mode on the document platen glass 14 and a document reading mode using the automatic document feeding unit 3, which can be set arbitrarily by the user. If the manual document reading mode on the platen glass 14 is selected, as shown in FIGS. The original 6 is placed on the holder, the original 6 is fixed with the original cover 2, and the image data of the original 6 is read while the optical system is moved.If 1 manual original reading mode is selected, the form of the original 6 is read. It is possible to read anything from a sheet-like object to a book-like object as image data.

On the other hand, when the document reading mode using the automatic document feeding unit 3 is selected, as shown in FIG. 1 and FIG. The image data of the original 6 passing through the static optical system is read while the original 6 is conveyed at a constant speed in the six directions of the arrows in Fig. 7. When this automatic original reading mode is selected, the sheet It is possible to automatically feed a large number of original documents 6 in succession, and it is possible to continuously feed up to 50 sheets of original documents 6, for example.

The operating system when the automatic document feeding unit 3 selects the document reading mode will now be described in more detail with reference to FIG.

That is, when the automatic document feeding unit 3 selects the document reading mode, the FL unit 10 moves to the position of the home position sensor 21 and is fixed at that position.

The original 6 is set upside down on the original tray 4. Further, the document 6 is sequentially transferred to the automatic document feeding unit 3 from the lower side.
taken within. The rotational force of the motor 30, which is a driving source, is transmitted to the pickup roller 31, the conveyance rollers (1) 34, and the like through gears and belts. (2)35. (3) Rotate 36. The original 6 is drawn into the automatic original feeding unit 3 by the pickup roller 31, and is passed through the separator 32.
At this time, if a plurality of documents 6 are fed in duplicate, the document double feeding prevention sensors 33 and 38 indicate the occurrence of an abnormality.

When the original document 6 is fed normally, the original document 6 moves to the left in FIG. At this time, the FL unit 10 waiting under the glass 44 illuminates the document 6, and the optical system of the main body 1 reads the image. Then, the original 6 is further conveyed to the left in FIG. 1 at a constant speed, and is ejected onto the original cover 2 (
(See reference numeral '6' in Figure 7).

As mentioned above, one document 6 has a resolution of 400 dp.
When reading iX 400dpi, for example, an A4 size document has a data amount of approximately 16Mbit, which is 8Mbit.
When transmitted at a clock rate of Hz, the data transmission time is about 2 seconds. Therefore, these two seconds are the waiting time for data exchange, during which the scanner
The next document 6 cannot be read. Therefore, when reading a large number of sheet-like originals 6 in succession, in preparation for reading the original image data, during the waiting time for data exchange between the previously sent original reading data and the host, the If the document 6 for which data reading is to be performed next is fed in advance to just before the data reading start position, the document feeding process can be performed within the waiting time for data exchange. The control circuit is shown in FIG. 2, and
The operating principle is that there is no paper jam, the previous document 6 has been ejected, and the document 6 is in the document tray 4. When these conditions are met,
The feeding of the original 6 is started, and the original passage detection sensor (1) 3
9 detects that the original 6 has been fed, and at this time, the counter gate is turned on and the original 6 is conveyed a distance corresponding to the set amount of the original stop position, and when the counter reaches O, the original 6 is fed. In this way, the document 6 is fed in advance to the document stop position (see reference numeral 50 in FIG. 1) immediately before the data reading start position. The time required for paper feeding is about 1 second, so when, for example, 50 originals are read continuously using the method of the present invention, the time can be reduced by 50 seconds.

[Effects of the Invention] The present invention is as described above, and according to the present invention, a large number of sheet-like originals set on a document tray are separated one by one and read continuously by a static optical system. In the automatic document reading system, image data reading speed can be increased as a result without adopting the technically extremely difficult method of increasing the speed of document separation that is performed prior to high-speed conveyance of the sheet document. It is possible to provide a document feeding control method for an image reading device that can be simulated as a document being read.

[Brief explanation of the drawing]

The drawings show an embodiment of an image reading apparatus to which the method of the present invention is applied, in which FIG. 1 is an explanatory diagram of the internal structure of the automatic document feeding unit 3, FIG. 2 is a control circuit diagram of the document feeding system, and FIG. is a perspective view showing the overall configuration of the image reading device, FIGS. 4 to 6 are explanatory diagrams of the operation in manual yX document reading mode on the document platen glass 14, and FIG. 7 is a document reading mode using the automatic document feeding unit 3. FIG. 3... Automatic document feeding unit, 6... Document, 10.
...FL unit, 39, 40 and 43...Original passage detection sensor, 50...Original stop position. 1st mouth 5 mouth 6th '10

Claims (1)

[Claims] 1. In an image reading method in which a large number of sheet-like originals set in a document tray are separated one by one and read continuously by a static optical system, when the multiple sheets of originals are read continuously, the original image is In preparation for data reading, during the waiting time for the data to be exchanged between the previously sent original scan data and the host, in parallel, the original to be read next is sent in advance to just before the data reading start position. A document feeding control method for an image reading device, characterized in that: