JPS61208970A - Picture reader - Google Patents

Abstract

PURPOSE:To accurately read the position of the original to be read by determining the start up timing of reading of an image sensor based on the output signal of the second sensor to detect the original located between a paper- supplying means and the image sensor. CONSTITUTION:The first original detecting sensor S1 located in the preceding stage of a paper-supplying roller 10 to detect the insertion of the original to the said roller 10, the second original detecting sensor S2 located between the roller 10 and the image sensor 1 to detect the original supplied, and the third original detecting sensor S3 located in the succeeding stage of the sensor 1 to detect the original delivered, are provided. The outputs from the sensors S1-S3 are supplied to a control part CPU which controls a motor 13 and the sensor 1 to transfer the read data to a computer COM. With the titled device with such constitution as the above, the sensor 2 detects the original being supplied at a constant speed, and the reading of the image of the original is started by making use of the timing from the said sensor. Therefore, the read- start-up position on the original is made accurate.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for reading an image of a document while feeding the document.
Regarding a reading device.

(Prior Art) In a conventional image reading device of this type, a document detection sensor is disposed before a paper feeding means, and based on the output of the document detection sensor, feeding of the document is started and image reading is started. The timing was set.

(Problem to be Solved by the Invention) By the way, the time from the detection of the original by the original detection sensor at the front stage of the paper feeding means to the start of feeding of the original by the paper feeding means depends on the condition of the insertion of the original and the amount of paper feed caused by the feeding means. It varies depending on the quality of the product. For this reason, the conventional apparatus has a problem in that the position at which image reading starts on the document fluctuates, and unnecessary portions may be read or, conversely, necessary portions may not be read.

The present invention has been made in view of this point, and its purpose is to
An object of the present invention is to realize an image reading device that can accurately read a predetermined position of a document to be read.

(Means for Solving the Problems) The present invention that solves the above problems includes an image sensor for reading an image of a document, a paper feeding means for feeding the document to the image sensor, and a paper feeding means for feeding the document to the image sensor. a first document detection hinge located in the front stage of the paper feeder for detecting insertion of a document into the paper feeder; and a first document detection hinge located between the paper feeder and the image sensor to detect the document being fed by the paper feeder. A second document detection sensor detects the document, and a third document detection sensor is located after the image sensor and detects the discharged document. The output of the second document detection sensor is used to determine the start timing of the means, the output of the second document detection sensor is used to determine the reading start timing of the image sensor, and the output of the third document detection sensor is used to confirm paper ejection. It is characterized by the fact that it can be used.

(Function) In the image reading device of the present invention, the reading start timing of the image sensor is determined based on the output signal of the second document detection sensor between the paper feeding means and the image sensor.

Therefore, the predetermined position of the document to be read can be accurately read.

(Example) Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 4 are main part configuration diagrams showing one embodiment of the present invention. In these figures, reference numeral 1 denotes a contact type one-dimensional image sensor (line sensor) that reads an original image by sliding the original into contact with the lower reading surface. The outer plates 3.4 forming the reading surface 2 of the image sensor 1 face each other with a constant gap 5 in the center. Inside this gap 5, a circuit section (not shown) for operating the reading section 6 of the image sensor 1 and the image sensor 1 is arranged. The reading unit 6 includes, for example, an LED array that irradiates light onto the document on the reading surface 2 through the gap 5, a SELFOC lens array that collects reflected light from the document surface through the gap, and the SELFOC lens array. It is composed of a COD, etc. that receives focused light at the Note that the array direction is a direction perpendicular to the paper plane of FIG.

The outer plate 4 of the image sensor 1 is extended to the right in FIG. 1, and the extended portion 4a is a part of the document guide (upper guide).
is formed. Guide members 7 and 8 guide the lower surface of the document and form a lower guide. Guide member 7
1 is a guide member facing the reading surface 2 of the image sensor 1, and a portion on the document feeding side is rotatably supported by a bin 9 (fixed to the main body of the apparatus, not shown). This guide member 7 is always urged toward the reading surface 2 of the image sensor 1 by a spring (not shown). Further, the guide member 8 is a guide member that is connected to the guide member 7 and is inclined toward the upper right in FIG. 1, and the substantially right half portion in FIG. 1 also functions as a document mounting table.

10 is a paper feeding roller provided on the feeding path formed by the guide member 8; 11 is a driven roller arranged so as to be in pressure contact with the paper feeding roller 10; 12 is a roller whose outer peripheral surface is outside the paper ejection side of the image sensor 1; The paper ejection row is in sliding contact with the plate 3. The circumferential speed of the paper discharge row 512 (moving speed of the outer circumferential surface) is selected to be the same as or slightly higher than the circumferential speed of the paper feed row 510 so that the document does not bend during reading. To specifically achieve this, if the outer diameters of both rollers are made equal, the rotational speed of the paper ejection row 59 should be the same as the rotational speed of the paper feed row 57.
Alternatively, if the rotational speed of both rollers is set to be the same, the outer diameter of the paper discharge row 512 may be set to be the same as or slightly larger than the outer diameter of the paper feed roller 10. Therefore, in the embodiment shown here, both rollers are driven at the same rotational speed, and the outer diameter of the paper discharge roller 12 is made slightly larger than the outer diameter of the paper feed roller 1o.

13 is a motor for feeding the document, and its output shaft 14
The gear 15 fixed to the roller shaft 1 of the paper feed roller 10
It is externally engaged with (meshing with) the gear 17 fixed to the gear 6. 18
is a timing belt for driving the paper ejection roller 12 at the same rotational speed as the paper feed roller 510, which includes a toothed pulley 19 fixed to the roller shaft 16 of the paper feed roller 10 and a roller shaft 20 of the paper ejection roller 12. It is wound between the toothed pulley 21 and the toothed pulley 21 fixed to the. The 0-ra shaft 22 of the driven 0-ra 11 is supported so as to be rotatable and movable in the vertical direction in FIG.

23 is a power source that generates and supplies a predetermined DC or AC voltage from a commercial power supply voltage; 24 is a circuit board for controlling various processes of the reading device, driving a motor, etc.; The power supply 23 and circuit board 24 are arranged below the document feeding path to the image sensor 1 in order to effectively utilize space.

In addition, in this embodiment, in order to control the sequence of image reading, the document is detected at a predetermined position using an optical sensor or a microswitch consisting of a light emitting diode and a photodiode or a phototransistor. It is being said. That is, a first document detection sensor S1 located upstream of the paper feed row 510 detects insertion of a document into the paper feed row 510, and a first document detection sensor S1 located between the paper feed roller 10 and the image sensor 1 A second document detection sensor S2 that detects the document being fed by the image sensor 1, and a third document detection sensor S3 that is located after the image sensor 1 and detects the document being discharged are provided. The outputs of these first to third document detection sensors S1 to S3 are input to the control unit CPU in the circuit board 24, as shown in FIG.
The PU controls the motor 13 and the image sensor 1 using this output, and transfers the read data to the other party's (external) computer COM.

Next, the operation of the above embodiment will be explained using FIGS. 5 and 6.

After the power is turned on and initialized, and image data can be transferred to the other party's computer COM, that is, when the ready signal of the computer COM is L'' (fifth (see figure (a)), paper feed roller 10
When a document is inserted between the driven roller 11 and the driven roller 11, the first document detection sensor S1 is turned on (see Fig. 5 (b)), and in synchronization with this, the motor 13 is turned on (started) (see Fig. 5 (h)). ), the document is fed to the left in FIG. 1 by the paper feed roller 10. Then, when the document is fed a certain amount, the second document detection sensor S2 is also turned on (see Figure 5 (d)).
. On the other hand, the document is then sent to the left in FIG. 1, passes through the reading surface 2 portion while being pressed against the reading surface 2 by the guide member 7, and is further sent to the left by the paper discharge row 512. The paper will be ejected. At this time of paper ejection, the third document detection sensor S3 is turned on (see FIG. 5(E)).

The control unit CPU operates for a predetermined period of time after the second document detection sensor S2 is turned on (from when the second document detection sensor S2 is turned on until the document reaches the reading position on the reading surface). After waiting tl (time: this is a constant value determined by the paper feeding speed by the paper feeding roller 10), a reading start pulse is sent to the image sensor 1 (see FIG. 5). As a result, actual image reading is started. And the second
Time t3(
Normally, j s = j t ) has elapsed and the predetermined reading is completed, the control unit CPU sends a reading end pulse to the image sensor 1 (see FIG. 5(G)), and then the third document detection sensor S3 The end of paper ejection (off) is confirmed from the output of , and the motor 13 is stopped.

Here, detection of document jam (JAM detection) will be described. Theoretically, the period from when the image sensor 1 starts reading until the document reaches the third document detection sensor S3 (
If the time (calculated) is t2, the time from turning on the second document detection sensor S2 to turning on the third document detection sensor S3 should be t1+t2. Therefore, if the third document detection sensor S3 is not turned on even after 1i1t+: has elapsed after the second document detection sensor S2 is turned on, with some margin given to t1+t2, it is considered that a jam has occurred. Therefore, the control unit CPU monitors the output of the third document detection sensor S3, and if it does not turn on within the time tE, it assumes that a jam has occurred and stops reading, and after stopping the motor 13, the operator asks the operator to clear the jam. prompt.

According to such a configuration, the second document detection sensor S2 detects the document being fed at a constant speed, and reading of the document image is started using this timing. The upper reading start position becomes accurate. Also, occurrence of jam can be easily confirmed.

Note that the present invention is not limited to the above embodiments, and various modifications are possible. For example, in the above description, the reading section 2 is used with the bottom surface, but the reading surface 2 may be used with the top surface or the side surface. Further, the close contact of the original to the reading section 2 can be achieved by simply arranging the guide member 7 with a very small distance from the reading section 2 (slightly larger than the thickness of the original).

Further, the paper feed roller 10 and the paper discharge roller 12 may be driven by separate motors. Then, the paper ejection roller 12
The driving may be synchronized with the turning on of the second document detection sensor S2.

(Effects of the Invention) As explained above, according to the present invention, the reading start timing of the image sensor is determined based on the output signal of the second document detection sensor between the paper feeding means and the image sensor. ing. Therefore, the predetermined position of the document to be read can be accurately read.

[Brief explanation of drawings]

FIG. 1 is AA in FIG. 2 showing one embodiment of the present invention.
Fig. 2 is a plan view showing the main parts of an embodiment of the present invention; Fig. 3 is a schematic diagram of the main parts corresponding to the 88 cross section of Fig. 2; FIG. 5 is a block diagram showing the electrical configuration of one embodiment of the invention, FIG. 5 is a timing chart showing the operation of the above embodiment, and FIG. 6 is a flow chart showing the operation of the above embodiment. 1... Image sensor 2... Reading surface 3.4...
Outer plate 6...Reading section 7.8...Guide member
10... Paper feed roller 11... Followed roller 12.
・・Paper ejection roller 15.17・・Gear 18・・Timing belt 19.21・・・Pulley 23・・・Power supply 24・・・Circuit board

Claims (1)

[Claims] an image sensor for reading a document image; a paper feeder for feeding the document to the image sensor; and a first sensor located upstream of the paper feeder to detect insertion of the document into the paper feeder. a second document detection sensor located between the paper feeding means and the image sensor and detecting the document fed by the paper feeding means; and a second document detection sensor located after the image sensor and discharging the paper. a third document detection sensor that detects a document being read, the output of the first document detection sensor is used to determine the start timing of the paper feeding means, and the output of the second document detection sensor is used to determine the start timing of the paper feeding means; is used to determine the reading start timing of the image sensor, and further, the output of the third document detection sensor is used to confirm paper ejection.