JP2974825B2 - Document feeder feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for feeding a document in a document reading apparatus such as an image scanner, and more particularly, to preventing a fed document from being obliquely set in a reading mechanism. Also, the present invention relates to a sheet feeding device of a document reading apparatus which is stable and improved so as to be able to increase the sheet feeding speed.

[0002]

2. Description of the Related Art For reading and recognizing items described in manuscripts and forms (collectively referred to as manuscripts for simplicity in the present specification) and inputting them to a data processing device. , An image input device and a document reading device are known. Such a document reading apparatus is configured to read characters or the like on a document to extract image information, and often includes an automatic reading unit that automatically conveys and reads a large number of documents.

The above automatic reading unit generally includes a pick mechanism for moving a plurality of documents stacked on a hopper to a predetermined preparation position, a separation mechanism for taking in one document placed in the preparation position, and A feeding mechanism for transporting the original, a reading mechanism for reading the transported original via optical means, a printing mechanism for printing on the original if necessary, and an ejection mechanism for discharging the original after reading to the stacker. Have. In this specification, the pick mechanism, the separation mechanism, the feed mechanism, and the discharge mechanism are collectively referred to as a document transport mechanism. In recent years, this document transport mechanism is generally controlled by a microprocessor.

FIG. 4 is a structural explanatory view schematically showing an example of a conventional document reading apparatus. In FIG. 4, 1 is a platen,
2 is a separation roller constituting a pick and separation mechanism, 3 is a feed roller constituting a feed mechanism, 4 is a reading mechanism,
Reference numeral 5 denotes a discharge roller constituting a discharge mechanism, which is arranged in the above-described order along the document conveying path. Feed roller 3
The discharge roller 5 is formed so as to rotate at the same peripheral speed in the direction of the arrow, that is, in the document conveying direction, via a pulley 6 and a belt 7 driven by a drive motor (not shown). The separation roller 2 is formed so as to rotate in the direction of the arrow via gears (not shown) directly connected to the feed roller 3, gears 8 and 9, and gears (not shown) directly connected to the separation roller 2. I have. Next, reference numeral 10 denotes a separation pad, which is provided with a leaf spring 10a.
The side a is formed so as to slide on the outer peripheral surface of the separation roller 2. Reference numeral 12 denotes a sensor, which is provided on the downstream side of the document conveying path near the feed roller 3.

With the above arrangement, when the pulley 6 is rotated by the drive motor, the separation roller 2, the feed roller 3
And the discharge roller 5 rotates in the direction of the arrow, so that the original (not shown) stacked on the original
, And transported to the feed roller 3. In this case, since the pressing force acts on the original by the leaf spring 10a, the original can be taken in and transported by the frictional force between the original and the separation roller 2. Even when a plurality of originals are taken in at the same time, only the originals that are in close contact with the separation roller 2 are conveyed by the blocking action of the separation pad 10. Next, the original is conveyed to the reading mechanism 4 by the feed roller 3, and immediately before that, the leading end of the original is detected by the sensor 12, and reading is started by a signal from the sensor 12. When the sensor 12 detects the trailing end of the document, the reading is terminated and the document is discharged out of the system by the discharge roller 5.

[0006]

In the conventional apparatus having the above structure, the separation roller 2 and the feed roller 3 rotate in the same direction as the direction in which the document is transported. As means for ensuring the interval, the peripheral speeds of the two rollers are made different, for example, the peripheral speed of the separation roller 2 is set to about 1/5 of the peripheral speed of the feed roller 3. For this reason, there is a problem that the processing speed of the entire document reading apparatus is limited by the paper feeding speed of the separation roller 2, and it is not possible to respond to high-speed processing, which has recently become strict.

Next, even when the leading edge of the document conveyed from the separation roller 2 to the feed roller 3 is inclined with respect to the document conveyance path (referred to as skew), there is no means for correcting or correcting this. , The skew directly appears in the read image, which not only significantly lowers the quality of the image, but may be recognized as erroneous information in extreme cases.

In order to solve the above problem, means for providing an aligning stopper so as to shut off the original transport path has been tried. In this case, after the alignment is completed, the aligning stopper is moved to the original transport path. Need to be evacuated. However, since the processing speed of the document reading device in recent years is gradually increasing, it is necessary to insert and retract the aligning stopper into the document conveying path at a high speed. In this case, the document may be damaged or wrinkled. There is a problem that it is extremely difficult to perform aligning and automatic sheet feeding without attaching.

Further, in the conventional paper feeder, since the taking-in and separation of the originals are performed by one separation roller 2, a plurality of originals are often conveyed. Cannot be increased. If the number of originals loaded on the original platen 1 increases,
There is a problem that a so-called double feed is easily generated due to the document biting into the separation pad 10.

Further, in the conventional paper feeder, since the original is pressed by the elastic force of the leaf spring 10a constituting the pick mechanism, the so-called pick force is constant, and the thickness of the original and the number of stacked sheets change. In this case, the initial transport force changes. On the other hand, the originals supplied to the reading device generally vary in thickness, size, the number of stacked sheets, and the like. In other words, the reading device can stably and reliably operate on the variously changing originals. It is required to have a proper paper feeding function. In this respect, the conventional paper feeding device cannot sufficiently cope with the problem, and there are limitations on the processed original.
In addition, there is a problem that the operation is complicated.

Further, since the conventional paper feeder employs a so-called trade-in paper feed system, a large number of originals 1 as shown in FIG.
When the document 3 is set on the document table 1 shown in FIG. 4, the leading edge of the document 13 is knife edge 13 as shown in FIG.
A pre-operation must be performed to form a. However, such a pre-operation is very complicated and often forgotten. As a result, the document feeding becomes not only smooth but also interrupted, so that the document reading device is idle and the processing efficiency is reduced.

The present invention solves the above-mentioned problems in the prior art, enables high-speed feeding of originals, can completely prevent double feed and skew, and can sufficiently cope with various originals. It is an object of the present invention to provide a sheet feeding device of a document reading apparatus capable of performing the above-described operations.

[0013]

In order to achieve the above object, first, in the present invention, as a basic configuration , a document transport mechanism for automatically transporting a plurality of documents stacked on a hopper, A document reading mechanism for reading the document via optical means, wherein the document transport mechanism includes at least a pick mechanism for moving the document loaded on the hopper to a predetermined preparation position; A pick roller and a separation roller, in which a pick and a separation mechanism are formed so as to be interlockable, in a paper feeder of a document reading apparatus having an automatic paper feed mechanism having a separation mechanism for taking in one sheet and a feed mechanism for conveying a document. And a pressure arm is slid on the pick roller, and a separation pad is slid on the separation roller. A feed roller which forms a feed mechanism is selectively rotatable in a direction opposite to the document conveying direction, and the document is conveyed in a predetermined direction after the leading end of the document is aligned. The technical means of composing was adopted.

In the first aspect of the present invention, the technical means in the above-mentioned basic structure is arranged such that a pick roller is provided on a swingable pick arm so that the pressing force on the document can be varied. And an operating arm formed to be rotatable selectively in conjunction with the pick roller is provided so as to be disengageable from the pick arm, and the pick arm is swung by the selective rotation of the operating arm. The technical means of increasing the pressing force of the roller against the document has been added.

In a second aspect of the present invention, the technical means in the above basic structure further comprises a platen forming a hopper formed so as to be swingable around a pick roller side and serving as an axis. An operation arm, which is rotatably formed in an interlocking manner, is detachably connected to the document table directly or via another rocking arm, and the document table is rocked by selective rotation of the operation arm. Therefore, a technical means of increasing the inclination angle of the original with respect to the horizontal plane was added.

[0016]

According to the above configuration, first, in the basic configuration ,
The pick mechanism is operated while the feed roller is rotated in the direction opposite to the document conveying direction. The original is taken in by the pick roller and the separation roller that constitute the pick and separation mechanism. However, the original taking-in position and the separation position are separate positions, and a gate is provided between the two rollers. Is reliably captured.
Also, even if a plurality of originals are taken in, the originals are separated by the gate and the separation pad, and only one original is fed to the feed roller. Next, when the document arrives at the feed roller, the feed roller rotates in the direction opposite to the document transport direction as described above, so that even if the document is skewed, the leading end thereof is easily aligned. You. Thereafter, by switching the rotation of the feed roller in a predetermined direction, the original is read and discharged out of the system as in the related art. During the rotation of the feed roller in the reverse direction, the separation roller and the discharge roller do not rotate, and the subsequent document does not collide with or overlap with the preceding document.

Next, in the first and second aspects of the present invention, in addition to the operation of the above-mentioned basic configuration, the operation of taking in the original is made more smooth and reliable.
That is, in the first invention, when the pressing force of the pick roller against the document is insufficient and the loading of the document is interrupted, the operating arm rotates to rotate the arm provided with the pick roller. Then, the pick roller is pressed against the original. With such an operation, the pressing force of the pick roller against the document increases, and the document can be taken in smoothly.

According to the second aspect , similarly to the first aspect , when the pressing force of the pick roller against the original is insufficient and the taking in of the original is interrupted, the operating arm is rotated to move the original. The tilt angle of the table with respect to the horizontal plane is increased. As a result, the inclination angle of the document on the document table is increased, so that the sliding action to the pick mechanism is promoted, and the document can be taken in smoothly.

[0019]

FIG. 1 is a structural explanatory view schematically showing the basic structure of the present invention, and the same parts are denoted by the same reference numerals as in FIG. In FIG. 1, reference numerals 2a and 2b denote a pick roller and a separation roller, respectively, for taking in and separating a document (not shown) stacked on the document table 1. That is, the pick roller 2a and the separation roller 2b are
It is formed so as to be able to interlock in the same direction via a gear (not shown) and a gear 14 directly connected to each other, and is also formed so as to be interlockable with the feed roller 3 via a gear 8. The pressing arm 11 is brought into sliding contact with the pick roller 2a, the separation pad 10 is brought into sliding contact with the separation roller 2b, and a gate 15 is interposed in the document conveyance path between the pick roller 2a and the separation roller 2b. Note that the pick rollers 2a,
A free wheel or a non-reverse clutch (not shown) is mounted on each of the shafts of the separation roller 2b and the discharge roller 5, and the separation roller 2b is rotated only in the counterclockwise direction.
Is formed so as to rotate only in the clockwise direction (document conveying direction). Reference numeral 16 denotes a sensor, which is provided downstream of the document conveying path near the separation roller 2b.

Next, the operation of the above configuration will be described. First, in FIG. 1, when the pulley 6 is rotated in the direction of the dashed arrow by a drive motor (not shown), the feed roller 3 is rotated by the belt 7 in the direction of the dashed arrow, that is, in the direction opposite to the document conveying direction. Since the discharge roller 5 has a non-reverse clutch, it does not rotate even if the belt 7 rotates. On the other hand, pick roller 2a and separation roller 2b
Is rotated in the direction of the dashed arrow by the gears 8 and 14. Accordingly, a document (not shown) stacked on the document table 1 is picked up one by one by the pick roller 2a and transported in the direction of the separation roller 2b. In this case, even when a plurality of originals are erroneously taken in, only the originals in close contact with the pick roller 2a and the separation roller 2b are conveyed toward the feed roller 3 by the blocking action of the gate 15 and the separation pad 10. You. Therefore, occurrence of an undesired state such as double feed can be completely prevented.

Next, even if the leading edge of the conveyed document arrives at the feed roller 3, the feed roller 3 moves
That is, since the document is rotated in the direction opposite to the document conveying direction, the document is not immediately fed to the feed roller 3 and slightly stagnates. Therefore, the original is aligned during this time. After the sensor 16 detects the leading edge of the document,
It can be controlled by a preset number of pulses or time. After a predetermined stagnation time has elapsed, the drive motor rotates in the reverse direction and the pulley 6 rotates in the direction indicated by the solid line arrow.
, The feed roller 3 and the discharge roller 5 also rotate in the direction of the solid arrow, and the document is conveyed and read. The subsequent operation is the same as that shown in FIG.

While the pulley 6, the feed roller 3 and the discharge roller 5 are rotating in the direction of the solid arrows, the pick roller 2a and the separation roller 2b are all in a stopped state. That is, since the non-reverse clutch is mounted on the pick roller 2a and the separation roller 2b, even if the gear 8 rotates in the direction of the solid line arrow, this rotation is not transmitted to the pick roller 2a and the separation roller 2b. Therefore, the subsequent document is not directly conveyed to the feed roller 3 rotating in the direction of the solid arrow.

After the trailing edge of the preceding document is detected by the sensor 12, after a predetermined number of pulses or a lapse of time, the drive motor rotates reversely, and the pulley 6, feed roller 3
Is rotated in the direction of the dashed arrow, and preparation for pre-alignment of the next document is completed. At the same time, the pick roller 2a and the separation roller 2b also rotate in the direction of the dashed arrow, and the next document is taken in. Even if the preceding document remains engaged with the discharge roller 5 during this time, since the discharge roller 5 is in the stopped state, the problem that the preceding document is transported in the reverse direction does not occur.

FIG. 2 is a structural explanatory view schematically showing a first embodiment of the present invention, and the same parts are denoted by the same reference numerals as in FIG. In FIG. 2, a pick arm 21 is provided on the shaft of the gear 14 so as to be swingable, and the pick roller 2a and the gear 22 are rotatably provided at the swing end.
The gear 22 is engaged with the gear 14. Reference numeral 23 denotes a spring, which extends between the swinging end of the pick arm 21 and the apparatus main body, and is formed so as to bias the pick arm 21 clockwise. Next, reference numeral 24 denotes a gear, which is rotatably provided by engaging with the gear 14, and an operating arm 25 is provided coaxially, and a rotating end of the operating arm 25 is disengageable from the pick arm 21. It is formed so that Gear 2
4 is equipped with a torque limiter (not shown), and the operating arm 25 rotates counterclockwise to
Is formed so as to limit the torque when turning the counterclockwise direction to a predetermined value or less. Reference numeral 26 denotes a sensor, which is disposed on a document conveying path between the pick roller 2a and the separation roller 2b.
For example, it is provided near the gate 15. Other configurations are the same bets also shown to in FIG. 1.

Next, the operation of the above configuration will be described. First, in FIG. 2, when the pulley 6 is rotated in the direction of the dashed arrow by a drive motor (not shown), the feed roller 3 is rotated by the belt 7 in the direction of the dashed arrow to prepare for pre-alignment when a document arrives. At the same time, the pick roller 2a and the separation roller 2b also rotate in the direction of the dashed arrow, so that a document (not shown) stacked on the document table 1 is taken in one sheet by the pick roller 2a and is fed via the separation roller 2b. is conveyed to 3, in FIG. 1
Pre-alignment similar to that shown is performed.

The pre-alignment time of the original by the feed roller 3 is controlled by a preset number of pulses or time after the passage of the original is detected by the sensor 26, as in the case of FIG. It is. In this case, for example, if the original is thick and the pick roller 2
When the document is not captured even by the rotation of a, that is, when the document does not reach the sensor 26, the gear 24 rotates via the gear 14 in the direction of the dashed arrow. And gear 14
The operating arm 25 provided coaxially with the pick arm 21 also rotates in the same direction, engages with the swinging end of the pick arm 21, and turns the pick arm 21 counterclockwise against the tension of the spring 23. . The rotation of the pick arm 21 causes the pick roller 2 to move.
Since a is pressed upward with a predetermined torque as a limit, the pressing force on the document can be increased and the document can be taken in reliably.

Next, after the document has been taken in, the feed roller 3
Is completed, the feed roller 3 rotates in the direction of the solid arrow, and the document is conveyed. On the other hand, by rotation of the feed roller 3 in the direction of the solid line arrow, a gear (not shown) provided coaxially with the pick roller 2a and the separation roller 2b also rotates in a direction opposite to that of FIG. Since the non-reverse clutch is mounted as described above, the vehicle is stopped without rotating. When the gear 14 rotates counterclockwise, the gear 24 rotates in the direction indicated by the solid arrow, so that the operating arm 25 separates from the pick arm 21 and returns to the original position shown in FIG. 2, for example.

FIG. 3 is a structural explanatory view schematically showing a second embodiment of the present invention, and the same parts are denoted by the same reference numerals as in FIGS. 1 and 2. In FIG. 3, the document table 1 is formed so as to be swingable around the pick roller 2a side as an axis, and is swingable from a position shown by a solid line to a position shown by a chain line, for example. Reference numeral 31 denotes a swing arm, which is swingably provided below the document table 1, and has a left end portion and an operation arm 33, which will be described later, and a right end portion, which is detachable from the bottom of the document table 1. Next, reference numeral 32 denotes a gear, which is rotatably provided by engaging with the gear 22, and an operating arm 33 is provided coaxially, and a rotating end of the operating arm 33 is connected to a left end of the swing arm 31. It is formed so that it can be disengaged. In addition, a torque limiter (not shown) is attached to the shaft of the gear 32,
The operation arm 33 is rotated clockwise, and the swing arm 31 is rotated.
Is formed so as to limit the torque when turning the counterclockwise direction to a predetermined value or less. Other configurations are the same as those of the first embodiment.

The operation of the above arrangement will be described below.
The description is omitted because it is the same as that of the first embodiment, and the operation of taking in the original will be described. First, for example, when the original is not taken in by the rotation of the pick roller 2a, that is, when the original does not reach the sensor 26, the gear 32 rotates via the gear 22 in the direction of the dashed arrow. An operating arm 33 provided coaxially with the gear 32 also rotates in the same direction, engages with the left end of the swing arm 31, rotates the swing arm 31 counterclockwise, and is indicated by a chain line. Rock to the position. Since the original table 1 is swung to the position shown by the chain line by the above swing of the swing arm 31, the inclination angle of the original with respect to the horizontal plane is increased, and the action of sliding the original into the pick roller 2a is promoted. Forming the state of (b),
This makes it easier to take in the manuscript.

Next, after the document is completely taken in, the feed roller 3
Is completed, the feed roller 3 rotates in the direction of the solid line arrow, and the document is conveyed. On the other hand, since the gear 32 rotates in the direction shown by the solid arrow through the intermediate gear train to be engaged, the operating arm 33 separates from the swing arm 31 and returns to, for example, the original position shown in FIG. In this case, the pick roller 2a and the separation roller 2b are in a stopped state without rotating as in the previous embodiment.

[0031]

Since the present invention has the above-described configuration and operation, the following effects can be obtained. (1) Since the pick and separation mechanism is composed of the pick roller and the separation roller, the document feeding speed can be increased, and the processing speed of the entire document reading apparatus can be greatly improved. (2) By improving the feed mechanism, the skew of the original can be corrected without providing an extra aligning stopper or the like, and the image quality after reading can be significantly improved without lowering the processing speed. (3) Since the reliability of taking in and separating documents by the pick mechanism is increased, double feed can be prevented and the number of documents that can be loaded on the hopper can be increased. (4) Since the initial transfer force in the pick mechanism is variable,
A stable initial conveyance force can be obtained without being affected by the state of the original when setting the original. (5) Even when a large number of originals are set, it is not necessary to pre-process the originals in advance, and the operability is significantly improved. (6) Not only is there no need for extra components for document pre-alignment processing, but also the operation from paper feeding to paper discharging can be performed by a single drive source, which simplifies the structure and reduces costs. Reduction is possible.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory diagram schematically showing a basic configuration of the present invention.

FIG. 2 is a configuration explanatory view schematically showing a first embodiment of the present invention.

FIG. 3 is a structural explanatory view schematically showing a second embodiment of the present invention.

FIG. 4 is a configuration explanatory view schematically illustrating an example of a conventional document reading apparatus.

5A and 5B are side views showing a state in which a large number of documents are stacked, wherein FIG. 5A shows a state before the operation and FIG. 5B shows a state after the operation.

[Explanation of symbols]

 2a Pick roller 2b Separation roller 3 Feed roller 15 Gate 21 Pick arm 25, 33 Operating arm 31 Swing arm

Continuation of the front page (72) Inventor Yasunori Miyauchi 98 Uno-ki-nu, Unoki-cho, Kawakita-gun, Ishikawa Pref. 202235 (JP, A) Japanese Utility Model Showa 61-163257 (JP, U) Japanese Utility Model Utility Model 2-57856 (JP, U) Japanese Utility Model Showa 56-47837 (JP, U)

Claims (2)

(57) [Claims] An original transport mechanism for automatically transporting a plurality of originals stacked on a hopper; and a reading mechanism for reading the transported originals via optical means, wherein the original transport mechanism comprises at least An automatic paper feed mechanism having a pick mechanism for moving a document stacked on the hopper to a predetermined preparation position, a separation mechanism for taking in one document placed at the preparation position, and a feed mechanism for conveying the document. And a pick roller and a separation roller, each of which is capable of interlocking a pick and a separation mechanism, and a pressure arm and a separation pad are provided for the pick roller and the separation roller, respectively. Each of the rollers is brought into sliding contact with each other, and a gate is interposed in a document conveying path between the pick roller and the separation roller. Rotatably formed in the opposite direction, as well as configured to convey the document was aligned above the tip of the document in a predetermined direction, the pick roller
Provided on a swingable pick arm to handle documents
The pick roller is formed so that the pressing force is variable.
The operating arm, which is formed to be rotatable selectively in conjunction with
The arm is detachably attached to the pick arm.
By swinging the pick arm by selective rotation, pick ro
Sheet feeding device of the document reading apparatus characterized by being configured to so that increasing the pressing force against the over La document. A plurality of originals stacked on a hopper;
Document transport mechanism that transports the document dynamically and optical transport of the document
And a reading mechanism for reading through the means.
At least, the document loaded on the hopper is
Pick mechanism to move to the fixed preparation position and the preparation position
Separation mechanism that takes in the original placed on the sheet and transports the original
An automatic paper feed mechanism having a feed mechanism for feeding
In a paper feeder of a document reading device, a pick-and-roll mechanism is formed so that a pick and a separation mechanism can be interlocked with each other.
Roller and separation roller,
Roller and a separation pad on the separation roller.
Sliding contact, document transport between pick roller and separation roller
A gate is interposed in the path to form the feed mechanism.
Roller can be selectively rotated in the direction opposite to the document transport direction
And then align the leading edge of the original before
And the hopper.
The platen can be pivoted around the pick roller side.
And can be rotated selectively in conjunction with the pick roller.
The formed working arm is directly or other swinging with the platen.
The arm can be disengaged via the moving arm,
The platen is oscillated by selective rotation so that the platen
Sheet feeder RuHara draft reading apparatus to <br/> characterized by being configured so as to increase the inclination angle against.