JPH0651536B2 - Document transport mechanism - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document transport mechanism that separates stacked documents one by one and transports them.

<Prior Art> As shown in FIG. 4, a document feeding system in a conventional facsimile apparatus, when a document 3 is inserted from a document insertion port 1 at the left end of the drawing, a pickup roller 5 is lowered and rotated to be mounted. The placed document 3 is sent out from the top to the right side of the drawing. The originals 3 sent out by the pickup roller 5 are separated one by one by the cooperation of the separation roller 8 and the separation guide 7, and are conveyed at a constant speed by the reading platen roller 12, while the image information is read by the reading sensor. And is configured to be discharged from the paper discharge port.

<Problems to be Solved by the Invention> In the above document conveying system, the stacked documents 3 must be accurately separated and conveyed one by one. For this purpose, the separation roller 8 and the separation guide 7 are used. It is necessary to strengthen the pressure contact force of.

Further, in the above-described document feeding system, when the stacked documents 3 are sequentially transported, the apparatus determines that the document is a single document and malfunctions unless a gap is created between the documents. Therefore, the document transport speed of the reading platen roller 12 is set higher than the document transport speed of the separation roller 8 so that a gap is formed between the transported documents. However, the original 3 being conveyed is separated by the separating roller 8 and the reading platen roller 12.
When they are engaged with each other, the separation roller 8 and the separation guide 7
If the pressure contacting force with is strong, a slip occurs between the platen roller 12 and the reading platen roller 12, and the conveyance speed of the document 3 is delayed. In this case, in the facsimile apparatus, if the original 3 is slower than a predetermined speed at the reading sensor position, the image information is read in a state of being stretched. Therefore, it is necessary to prevent the reading platen roller 12 from slipping when the document is conveyed, and for that purpose, it is necessary to weaken the pressure contact force between the separation roller 8 and the separation guide 7.

That is, in the document conveying system, there is a problem that the contradictory conditions cannot be satisfied at the same time in order to prevent the double feeding of the documents and to convey the documents at a constant speed.

The present invention relates to a completely new technique developed to solve the above problems.

<Means for Solving Problems> A typical means for solving the above problems according to the present invention is capable of moving up and down between a separating position and a pressure contact position, and descending to the pressure contact position to perform stacking. And a feeding means for feeding the manuscript
Separation means having a separation rotator for separating the originals sent out by the feeding means one by one and a separation guide in pressure contact with the separation rotator, and the separated originals downstream of the separation means When the feeding means for further feeding the feeding means and the feeding means are in the pressure contact position, the pressing force of the feeding means is transmitted to the separating means to increase the pressure contact force of the separating means, and conversely the feeding means separates. A force transmission means interposed between the feeding means and the separating means so as to release the pressing force of the feeding means from the separating means to weaken the pressure contact force of the separating means when in the position. When the conveying means conveys a document, the feeding means is in the separated position and the elevation of the feeding means is controlled so that the pressure contact force is weakened.

<Operation> According to the above means, when the feeding means descends to the press contact position,
The force transmitting means transmits the pressing force of the feeding means to the separating means to increase the pressure contact force of the separating means, and separates the originals sent by the feeding means one by one.

Further, when the conveying means conveys the separated original, the feeding means moves up to the separated position, and the force transmitting means releases the pressing force of the feeding means from the separating means to press the separating means. Is weakened and the carrying operation is performed.

<Embodiment> Next, an embodiment of the present invention in which the above means is applied to a facsimile apparatus will be described.

FIG. 1 is a cross-sectional explanatory view of a facsimile machine incorporating a mechanism according to an embodiment of the present invention. The left side of the figure is a front part, and the right side is a rear part.

A document insertion opening 1 is provided at the front end, and the vicinity of the insertion opening 1 is lowered by a document presence / absence sensor 2 and a signal from the sensor 2 while being pressed against the document 3 and by the cooperation with the document guide 4, A pickup roller 5 is provided which constitutes a feeding means for feeding the original 3 backward.

Further, behind the pickup roller 5, there is provided a separation roller 8 which is pressed against a separation guide 7 urged by a separation spring 6 to separate the stacked originals 3 one by one.

Further, in the rear of the separation roller 8, the lower guide 10 and the upper guide 11 urged by a spring 9 cooperate with each other to convey the original 3 at a constant speed while making a U-turn along its peripheral surface. A reading platen roller 12 as a means is provided, and a small sensor (so-called contact type sensor, same-magnification sensor, etc.) 13 for reading image information of the document 3 being conveyed is provided on the upper rear portion of the reading platen roller 12. At the same time, a document edge detection sensor 14 for detecting the edge of the document 3 being conveyed is arranged below the document.

In the figure, reference numeral 15 is a document discharge port provided on the outer cover 16, and 17 is a recording head that constitutes a recording unit, and a recording material conveyed by the recording platen roller 12 in accordance with predetermined image information ( Paper, plastic sheet, etc.) 19.

Next, the structure of the separation guide 7 will be described in detail.
The separation guide 7 is constructed integrally with the document guide 4 and is bent at its connecting portion so that it can be rotated about the bent portion by a fixed rotating shaft 20.

Therefore, when the pickup roller 5 descends and presses the document guide 4 as a force transmitting means, the separation guide 7 presses the separation roller 8 by the principle of leverage, and the pressure contact force between the two is strengthened.

Next, the operation when the apparatus configured as described above is driven will be described centering on the document conveying system.

When a plurality of originals 3 are inserted through the insertion opening 1, the original presence sensor 2 detects this and the pickup roller 5 descends to press the original guide 4 and send out the original 3. The fed originals 3 are separated one by one from the upper part of the stack by the separating roller 8 and are conveyed to the reading platen roller 12. In the above state, the distance from the contact point between the pickup roller 5 and the document guide 4 to the rotating shaft 20 is a, and the distance from the rotating shaft 20 to the contact point between the separation guide 7 and the separating roller 8 is b pickup roller. If the force by which 5 presses the document guide 4 is w and the force by which the separation spring 6 and the separation guide 7 are pressed is p, the pickup roller 5 descends and the separation guide 7 is pressed when the document guide 4 is pressed. Separation roller 8
Pressing force Pa of Becomes

After that, when the document 3 is conveyed by the reading platen roller 12 and the leading edge of the document 3 is detected by the document edge detection sensor 14, the pickup roller 5 rises, the document 3 is conveyed by the reading platen roller 12 at a constant speed, and a small sensor 13 is provided.
The image information of the original 3 is read by.

As described above, when reading the image information of the original 3,
Since the pickup roller 5 does not press the document guide 4, the pressure contact force Pb between the separation guide 7 and the separation roller 8 is only the force p by the separation spring 6.

Therefore, Pb = p.

After that, when the document edge detection sensor 14 detects the trailing edge of the document 3 which is being conveyed in a U-turn along the peripheral surface of the reading platen roller 12, the pickup roller 5 descends again and the two of the stacked documents 3 are detected. The subsequent sheets are similarly conveyed.

In the above case, Pb, that is, the pressing force p of the separation spring 6 is
The reading platen roller 12 is set to a range that does not affect the constant speed conveyance of the original 3, and Pa is set to a, b, and w in a range where the separation roller 8 does not cause double feeding.

Next, an embodiment in which the pickup roller 5 is composed of a small diameter half-moon portion 21 and a large diameter half-moon portion 22 as shown in FIG. 3 will be described.

As described above, the pickup roller 5 according to this embodiment does not move up and down, and in the document standby state, the small-diameter half-moon portion 21 faces downward, and the pickup roller 5 and the document guide 4 are separated from each other. The large-diameter half-moon portion 22 is pressed against the document 3 (indicated by a broken line in the drawing) when a gap is generated and the device is rotated in an operating state, and the document 3 is sent out by the cooperation of the document guide 4.

Therefore, in the pickup roller 5 having the above structure,
When the roller 5 operates to send out the original 3, the large-diameter half-moon portion 22 of the pickup roller 5 presses the original 3 and the original guide 4 (pressing force = w), and then the original end detecting sensor 14
Detects the leading edge of the original and the reading platen roller 12 conveys the original at a constant speed, the pickup roller 5 is in a standby state and the original guide 4 is not pressed.

Therefore, even in the case of the pickup roller 5 having the above structure, the pressing force of the roller 5 can be converted into the pressure contact force between the separation guide 7 and the separation roller 8.

<Effects of the Invention> According to the present invention, as described above, the force transmitting means such as the document guide is provided to convert the pressing force of the feeding means such as the pickup roller into the pressure contact force of the separating means, and the feeding means sends out the document. In this state, the pressure contact force of the separating means is strengthened to enhance the separating action of the stacked originals, and the pressure contact force of the separating means is weakened during the conveyance by the downstream conveying means. Can be removed.

Moreover, for that reason, it is not necessary to separately configure the driving means of the solenoid.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view in which a document feeding system according to an embodiment of the present invention is incorporated in a facsimile machine, FIG. 2 is an explanatory diagram of the relationship between a document guide and a separation guide, and FIG. 3 is an explanatory diagram of another embodiment. , FIG. 4 is an explanatory diagram of a conventional technique. 1 is a document insertion slot, 2 is a document presence / absence sensor, 3 is a document, 4
Is a document guide, 5 is a pickup roller, 6 is a separation spring, 7 is a separation guide, 8 is a separation roller, 12 is a reading platen roller, 13 is a small sensor, 14 is a document edge detection sensor, 15 is a document discharge port, 20 Is a rotating shaft, 21 is a small diameter half-moon, and 22 is a large diameter half-moon.

Claims (1)

[Claims] Claims: 1. It is possible to move up and down between the separated position and the pressure contact position,
A feeding unit that descends to the pressure contact position and feeds the stacked originals, a separating rotary body for separating the originals fed by the feeding unit one by one, and a separation guide that presses the separating rotary body. When the separating means has a separating means, a conveying means that is downstream of the separating means and further conveys the separated original, and the feeding means is in a pressure contact position, the pressing force of the feeding means is applied to the separating means. So as to increase the pressure contact force of the separating means, and conversely, when the feeding means is in the separated position, release the pressing force of the feeding means from the separating means to weaken the pressure contact force of the separating means, Force transmitting means interposed between the feeding means and the separating means, the feeding means is in the separated position so that the pressure contact force is weakened when the feeding means conveys the document. A source characterized by controlling the elevation of the feeding means Transport mechanism.