JPH07277553A - Document carrying device - Google Patents

Abstract

PURPOSE:To surely carry documents without resetting the documents even if the sending of a document stops. CONSTITUTION:When starting the carrying of a document at the specified speed, a control section 20 starts a timer (t), and if a document detecting sensor S does not detect the document after the lapse of the specified time, the control section 20 performs document carrying at a half speed of the specified speed again. If the document detecting sensor S does not detect the document after the lapse of the specified time after the start of the document at a half speed of the specified speed, the control section 20 changes the speed to 1/4. If the sensor S does not detect the document, the control section 20 changes the speed to 1/8-1/2n (n is natural number) in order.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document feeder for a facsimile machine, a copying machine, a printer or the like.

[0002]

2. Description of the Related Art Generally, as a document transportation error, there are no feeding (non-feeding) in which a document is not transported, feeding of two or more sheets (multi-feed), jamming and the like. Conventionally, as an apparatus of this type, for example, Japanese Patent Laid-Open No. 1-22
As disclosed in Japanese Patent Publication No. 09997, when a conveyance error occurs, the stepping motor is driven at a frequency other than its response frequency and within an audible frequency to stop the stepping motor and generate a vibration sound, thereby causing an abnormality to the operator. It is known to use a notification sound.

[0003]

However, in the above-mentioned conventional apparatus, when the conveyance error occurs, the stepping motor is stopped and an abnormal alarm sound is generated. Must be reset.

The present invention has been made in view of the circumstances of the prior art as described above, and an object thereof is to convey an original without the operator performing an operation of resetting the original when the original is not fed. An object of the present invention is to provide a document feeder that can reliably perform the operation.

[0005]

In order to achieve the above object, a first means is a stepping motor for driving a roller for conveying an original, a detecting means for detecting a non-feed of the original, and the stepping motor. Is driven at a predetermined speed to start feeding the original, and when the detecting means detects the non-feed of the original, the speed of the stepping motor is set to 1 / 2n (n = 1, 2, ...) Of the predetermined speed. That is, a control means for sequentially changing the document number to a natural number) and restarting the conveyance of the document is provided.

A second means is to operate when the control means of the first means drives the stepping motor at a predetermined speed to start feeding an original, and the detecting means detects a non-feed of the original. When the speed of the stepping motor is changed to ½ of the predetermined speed and the document conveyance is restarted, and the detecting means detects again the non-feed of the document, the speed of the stepping motor is ¼ of the predetermined speed. It is characterized in that the document is restarted after being changed to.

A third means is a stepping motor for driving a roller for conveying an original, a detecting means for detecting a non-feed of the original, and the stepping motor is driven at a predetermined speed to start the original conveyance. When the detection unit detects that the document has not been fed, the control unit reverses the stepping motor and then rotates the stepping motor in the forward direction to restart the document conveyance.

According to a fourth means, in the third means, when the control means restarts the conveyance of the original document and the detection means detects again the non-feed of the original document, the speed of the stepping motor is set to the predetermined speed. It is characterized by sequentially changing to 1 / 2n (n is a natural number).

The fifth means includes a roller pair including a first roller for feeding the original in the third or fourth means and a second roller for separating the original bundle, and the control means includes the stepping means. Both the first roller and the second roller are reversely rotated when the motor is reversely rotated.

A sixth means is such that when the control means of the fifth means reverses both the first roller and the second roller, the linear velocity of the second roller is the first roller. The feature is that the control is performed so as to be faster.

[0011]

In the first means, when it is detected that the document has not been fed, the stepping motor is driven at 1 / 2n of the predetermined speed to restart the document transportation. If the speed of the rollers that convey the original is slower, the coefficient of friction of the rollers will increase, and the original will be more likely to be conveyed.If the original is not fed, the original will not need to be reset by the operator. Transport is performed. Further, by conveying at 1 / 2n of the predetermined speed, it is possible to synchronize with the reading speed in a facsimile machine or a copying machine.

According to the second means, when it is detected that the document has not been fed, the stepping motor is driven at 1/2 or 1/1 / the predetermined speed.
In step 4, the document is resumed to be conveyed again, and when the document is not fed, the operator does not need to reset the document. Further, it can be synchronized with the reading speed in a facsimile machine having a mode for reading a document at 1/2 or 1/4 of a predetermined speed.

In the third means, when the document non-feed is detected, the stepping motor rotates in the reverse direction and then rotates in the normal direction, so that two or more documents enter the document separating section and a non-feed occurs. In this case, it is easy to return to the original state and separate the sheet during re-conveyance, and therefore, it is not necessary for the operator to reset the original.

In the fourth means, when it is detected that the document has not been fed, the document is returned in the reverse direction, and then the stepping motor is driven at 1 / 2n of the predetermined speed to restart the document transportation. When the speed of the rollers that convey the original document becomes slow, the coefficient of friction of the roller becomes large, and the possibility that the original document will be conveyed increases, and when the document is not fed, it is not necessary for the operator to reset the original document. . Also, 1 / 2n of the predetermined speed
By carrying by, the reading speed can be synchronized with a facsimile machine or a copying machine.

In the fifth means, both the first roller for feeding the original and the second roller for separating the original bundle are reversed, so that the leading end surface of the original bundle is flattened to facilitate separation during re-conveyance. be able to.

In the sixth means, since the linear velocity of the second roller for separating the document bundle is faster than that of the first roller for feeding the document,
The original on the side of the first roller protrudes from the original on the side of the second roller, and can be easily separated when re-conveyed.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a document feeder according to the present invention, and FIG. 2 is a block diagram showing a facsimile apparatus equipped with the document feeder of FIG.

First, referring to FIG. 2, a facsimile apparatus equipped with the document feeder of this embodiment will be described. The operation board 1 is provided with various keys required for a facsimile apparatus and a display unit including an LCD. As the display unit, a known display device can be used in addition to the LCD. A plurality of originals 2 are collected by the user, and the leading end of the originals 2 passes through the pressure plate 3 and the pickup roller 4 and is set so as to come into contact with the nip portion of the separation roller 5 and the feed roller 6.

In this set state, the uppermost original 2 is pressed by the upper pressure plate 3 and the lowermost original 2 is taken in by the pickup roller 4. When a plurality of originals 2 are taken in by the pickup roller 4, the lowermost original 2 is separated and taken in by a roller pair composed of a separation roller 5 and a feed roller 6.

This original 2 is conveyed by a pair of conveying rollers 7 and illuminated by a light source 8 so that its reflected light is reflected by the reflecting mirror 1.
It is reflected by 0, read by the image forming system 9, and discharged by the paper discharge roller pair 11. The roll paper 12 is conveyed between the thermal head 13 and the platen roller 14 to form an image, cut by the cutter 15, and discharged by the paper discharge roller pair 16.

The pressure plate 3, the pickup roller 4, the separating roller 5 and the feed roller 6 constitute a separating section A, and this separating section A also serves as a stepping motor M (FIG. Driven). Separation part A
Is determined by the feed roller 6, and the reading speed and the conveying speed are synchronized with the linear velocity of the conveying roller pair 7. Here, it is said that the coefficient of friction does not depend on the speed, but actually, the coefficient of friction tends to decrease as the speed increases, and therefore, the conveying force of the feed roller 6 decreases as the reading speed increases. No feed
Is likely to occur.

Next, the configuration of the control system will be described with reference to FIG. The document detection sensor S is arranged in the conveyance path between the feed roller 6 and the conveyance roller pair 7, and the control unit 20 controls the speed of the stepping motor M based on the detection signal of the document detection sensor S and the value of the timer t. . That is, the control unit 2
In the case of 0, the timer t is started when the conveyance of the document 2 is started at a predetermined speed, and when the document detection sensor S does not detect the leading edge of the document 2 even after the predetermined time elapses, the document 2 is conveyed at a speed of 1/2. Do it again.

If the original detection sensor S does not detect the original 2 even if a predetermined time elapses after carrying at the speed of 1/2, the value is changed to 1/4, and from 1/8 to 1 below. / 2n
(N is a natural number, the same applies hereinafter), and the conveyance is performed again at a reduced speed. The reason for lowering the carrying speed such as 1 / 2n is to synchronize the carrying speed and the reading speed. Further, in a facsimile machine, the reading resolution is usually three modes: standard (= 1/1), detail (= 1/2), and fine (= 1/4). 1/4 of
Up to.

Next, the operation of the second embodiment will be described with reference to FIG. When the conveyance of the document 2 is started at a predetermined speed, a timer t is started and the leading edge of the document 2 is detected by the document detection sensor S.
When the document detection sensor S detects the document 2 (t <t0) during the predetermined time t0 before passing through and the predetermined time t0 elapses, the stepping motor M is normally rotated (steps S1 → S5). ).

On the other hand, if the document detection sensor S does not detect the document 2 even after the lapse of a predetermined time t0 after the document 2 starts to be conveyed, the motor M is once rotated in the reverse direction (steps S1 → S).
2) Then, the motor M is normally rotated at ½ of the starting speed (step S3). Then, if the document detection sensor S does not detect the document 2 even after the lapse of a predetermined time t1, the reverse rotation and the forward rotation are repeated (steps S4 → S6 → S).
2), the number of repetitions n of the reverse rotation and the forward rotation is a predetermined number n0
If it exceeds, an error is displayed (step S6 → S
7). When the original detection sensor S detects the original 2 after the predetermined time t1 has passed after the reverse rotation and the normal rotation, the normal rotation is continued to perform the reading (step S4).
→ S5).

That is, for example, as shown in FIG. 4A, a state in which a plurality of originals 2 are not set in line (for example, the user puts the original bundle 2 in the nip portion between the separation roller 5 and the feed roller 6 excessively When the conveyance is started in the pressed state), the leading edge of the document bundle 2 is narrowed down by the separation roller 5 and the feed roller 6 as shown in FIG.
Even if it is set to / 2, it may not be separated and may not be conveyed.

Therefore, as shown in FIG. 5 (a), no feed can be prevented by reversing the feed roller 6 and returning the original 2 to its original state. Further, as shown in FIG. 5B, when only the feed roller 6 is reversed and the separation roller 5 is not reversed, the central document of the document stack 2 is projected, that is, a state like a so-called pencil tip, When the transport is restarted in this state, multi-feed is performed.

Therefore, by reversing both the separation roller 5 and the feed roller 6, it is possible to prevent the multi-feed by making the leading end surface of the original stack 2 flat as shown in FIG. 6 (a). In this case, the separation roller 5
6 (a) by increasing the linear velocity of the feed roller 6 faster than the feed roller 6 and returning a large amount of the original 2 on the separation roller 5 side, that is, the upper side.
As shown in, the original 2 on the feed roller 6 side, that is, on the lower side
The lowermost original 2 can be easily taken into the re-conveyed character by the feed roller 6 and can be easily separated.

[0029]

As described above, according to the first aspect of the invention, when the document non-feed is detected, the stepping motor is driven at a predetermined speed 1 / 2n with n being a natural number, and the document conveyance is restarted. Therefore, if the speed of the roller that conveys the original becomes slower, the coefficient of friction of the roller will increase and the possibility that the original will be conveyed becomes higher. The document is reliably conveyed without performing the operation. In addition, 1 / the predetermined speed
By conveying the sheet at 2n, it is possible to synchronize with the reading speed in a facsimile machine or a copying machine.

According to the second aspect of the present invention, when the non-feed of the original is detected, the stepping motor is 1 / th of the predetermined speed.
Since the originals are restarted by being sequentially driven by 2/4, the originals can be reliably conveyed without the operator performing the operation of resetting the originals when the originals are not fed. Further, it can be synchronized with the read image in a facsimile machine having a mode for reading a document at 1/2 or 1/4 of a predetermined speed.

According to the third aspect of the present invention, when the document non-feed is detected, the stepping motor is rotated in the reverse direction and then rotated in the normal direction, so that two or more documents enter the document separation section and are not fed. When it occurs, it returns to its original state and easily separates when it is re-conveyed. Therefore, the operator can convey the document without resetting the document.

According to the fourth aspect of the invention, when the document is not fed, the document is returned in the reverse direction, and then the stepping motor is driven at 1 / 2n of the predetermined speed to restart the document transportation. , When the speed of the roller for conveying the original document becomes slow, the coefficient of friction of the roller becomes large and the original document is likely to be conveyed, and if the original document is not fed due to this, the operator resets the original document. The document can be reliably transported without performing any operation. Further, by conveying at 1 / 2n of the predetermined speed, it is possible to synchronize with the reading speed in a facsimile machine or a copying machine.

According to the fifth aspect of the present invention, both the first roller for feeding the original and the second roller for separating the original bundle are reversed, so that the leading end surface of the original bundle is flattened and separated during re-conveyance. The original can be conveyed, and therefore the operator can convey the original without resetting the original.

According to a sixth aspect of the invention, since the linear velocity of the second roller for separating the document bundle is faster than that of the first roller for feeding the document, the document on the first roller side is the document on the second roller side. It can be more protruded and can be separated easily when re-conveying,
Therefore, the document can be reliably conveyed without the operator performing an operation of resetting the document.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a document feeder according to the present invention.

FIG. 2 is a block diagram showing a facsimile machine equipped with the document feeder of FIG.

FIG. 3 is a flowchart for explaining the operation of the document feeder of the second embodiment.

FIG. 4 is an explanatory diagram showing a document in a multi-feed state.

FIG. 5 is an explanatory diagram showing an operation of returning a document in a multi-feed state.

FIG. 6 is an explanatory diagram showing a state where a document in a multi-feed state has returned.

[Explanation of symbols]

 2 original 5 separation roller 6 feed roller 20 control section S original detection sensor t timer M stepping motor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical indication H04N 1/00 J 1/04

Claims (6)

[Claims] 1. A document transporting device for transporting a plurality of stacked sheet documents one by one through rollers to convey them to a predetermined location, and a stepping motor for driving the rollers and detecting non-feeding of the documents. When the detection means and the stepping motor are driven at a predetermined speed to start the conveyance of the document, and the detection means detects the non-feed of the document, the speed of the stepping motor is set to 1 / n of the predetermined speed, where n is a natural number. A document feeding device, comprising: a control unit that sequentially changes the number to 2n and restarts document feeding. 2. The control means drives the stepping motor at a predetermined speed to start the conveyance of an original, and when the detecting means detects the non-feed of the original, the speed of the stepping motor is set to the predetermined speed. If the detection means detects the non-feed of the original again, the speed of the stepping motor is changed to 1/4 of the predetermined speed and the original transportation is restarted. The document feeder according to claim 1, wherein: 3. A document transporting device for transporting a plurality of stacked sheet documents one by one through rollers to transport them to a predetermined location, and a stepping motor for driving the rollers and detecting non-feeding of the documents. The detection means and the stepping motor are driven at a predetermined speed to start the conveyance of the document, and when the detection means detects the non-feed of the document, the stepping motor is rotated in the reverse direction and then rotated in the forward direction to convey the document. And a control unit that restarts the document. 4. The control means sets the speed of the stepping motor to 1 / 2n of the predetermined speed when n is a natural number when the detection means detects again the non-feed of the original after restarting the conveyance of the original. The document feeder according to claim 3, wherein the document feeder is changed sequentially. 5. A pair of rollers including a first roller for feeding a document and a second roller for separating a bundle of documents, wherein the control means includes the first roller when the stepping motor is reversely rotated. 5. The document feeder according to claim 3, wherein both the first roller and the second roller are reversed. 6. The control means controls the linear velocity of the second roller to be higher than that of the first roller when both the first roller and the second roller are reversed. The document feeder according to claim 5, wherein: