JPH04313570A - Both side paper feeding device and both side paper feeding method - Google Patents

Abstract

PURPOSE:To provide a both sides paper feeding device and a both sides paper feeding method capable of lessening the abrasion of a feeding roller and a separating roller, preventing a torque rise due to the reversal rotation of the separating roller, and preventing the back soiling by reversely rotating the separating roller with an inexpensive means. CONSTITUTION:A feeding roller 3 is applied by rotation force in the direction reverse to a feeding direction because a separating roller 4 pressure contacted with the feeding roller 3 to rotate reversely when an electromagnetic clutch 8 is off. Then a delivery roller 2 is made unrotative reversely by providing a one way clutch on a gear 5 and bringing the reverse direction rotation of the feeding roller 3 into a free condition.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a double-sided paper feeding device and a double-sided paper feeding method, and in particular, a double-sided paper feeding device and a double-sided paper feeding method using a bottom-feed friction separation method used in facsimile machines, printers, etc. Regarding.

0002

[Prior Art] In a bottom-feeding friction separation method in a duplex paper feeder, multiple sheets of transfer paper that have been copied on one side are stacked with the copied side facing up, and the bottom paper is fed from the stacking section. In this case, if the separation roller to prevent double feeding is fixed, the bottom paper will be fed with the leading edge of the second sheet sandwiched between the nip between the separation roller and the feed roller.

0003

However, in the prior art, as described above, the bottom paper is fed with the leading edge of the second paper being sandwiched between the nip of the separation roller and the feed roller. , the image on the bottom paper of transfer paper 1 rubs against the leading edge of the second sheet, and the leading edge of the second sheet gets dirty (see Figure 5).
. For this back dirt, the leading edge of the second sheet is separated by the separation roller 4.
It is effective to reverse the separation roller 4 so that it does not get caught in the nip of the feed roller 3. 2 is a feeding roller. As a prior art of this kind, Japanese Patent Application Laid-Open No. 61-20675
There is a publication No. 1, and it is shown in FIG. As shown in FIG. 6, when the separation roller 4 is reversed in synchronization with the feed roller 3,
Normally, the feed roller 3 is not driven when the transfer paper is bitten by the roller on the downstream side, so the reversal of the separation roller 4 is also stopped, and back staining occurs. In addition, when the separation roller 4 is always reversed, the torque increases or the feed roller 3, the separation roller 4,
This will result in increased wear. Also, separation roller 4 only for paper feeding etc.
When reversing the feed roller 3, an electromagnetic clutch, for example, is required to turn on and off a drive connection other than the feed roller 3, which increases costs.

The present invention has been made in view of the above-mentioned problems of the prior art, and aims to reduce wear of the feed roller and separation roller, prevent torque increase due to reversal of the separation roller, and provide an inexpensive method. To provide a double-sided paper feeding device and a double-sided paper feeding method capable of preventing reverse staining by reversing separation rollers.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a stacking platform for stacking transfer paper of one-sided copied transfer paper, and a transfer paper stacked on the stacking platform for transferring the transfer paper to the lowest sheet. A feeding device that has a feeding roller that feeds the paper to feed the paper, a feed roller located downstream of the feeding roller in the paper feeding direction, and a separation roller that is in pressure contact with the feed roller and rotates in a direction opposite to the paper feeding direction. In this case, the feed roller can rotate in the feeding direction and the opposite direction, and when the feed roller rotates in the feeding direction, the feeding roller rotates in the feeding direction synchronously, and when the feed roller rotates in the opposite direction, the feeding roller does not rotate. The present invention also includes a loading table for loading transfer paper that has been copied on one side, and a feeding roller that feeds the transfer paper stacked on the loading table starting from the lowest paper. , a feeding device including a feed roller located downstream of the feeding roller in the paper feeding direction, and a separation roller that is in pressure contact with the feed roller and rotates in the opposite direction to the paper feeding direction, the feed roller is rotated in the paper feeding direction and the opposite direction. When the feed roller rotates in the delivery direction, the delivery roller synchronously rotates in the delivery direction, and when the feed roller rotates in the opposite direction, the delivery roller synchronously rotates in the delivery direction.When the feed roller rotates in the opposite direction, the delivery roller It is configured to feed paper without rotating.

[0006]

[Operation] By the above means, the separation roller is reversed, and the feed roller can be reversed during non-feeding, and even if the feed roller is reversed, the feeding roller is not reversed, so there is less wear on the feed roller and separation roller, and the separation is improved. To prevent an increase in torque due to roller reversal, and to prevent reverse staining by reversing the separation roller using an inexpensive means.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 4. FIG. 1 is an explanatory diagram showing the main parts of a duplex paper feeder according to the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG.
2 is a view taken along arrow D in FIG. 2, and FIG. 4 is a partially cutaway perspective view. FIG. 1 shows the rotational direction of each roller during paper feeding in a double-sided paper feeding device according to the present invention. In this Figure 1,
1 is a transfer paper, 2 is a feed roller, 3 is a feed roller, and 4 is a separation roller. The transfer paper 1 is fed to the left by the rotation of the feed roller 2 and feed roller 3 in the direction of the arrow, and the separation roller is reversed. The rollers 4 separate the second and subsequent sheets of transfer paper 1 to prevent them from being fed together with the first sheet. When feeding paper, the electromagnetic clutch 8 is turned on, and as shown in FIG. 2, the driving force is transmitted from the gear 9 to the shaft 3'.
The feed roller 3 fixed to is rotated in the feeding direction. Furthermore, the feeding roller 2 is also rotated in the feeding direction together with the shaft 2' by the gears 7, 6, and 5 from the shaft 3'. When the electromagnetic clutch 8 is off, the separation roller 4 is in pressure contact with the feed roller 3 and rotates in reverse (in the opposite direction to the feeding direction), so that a rotational force in the opposite direction to the feeding direction is applied to the feed roller 3. Therefore, a one-way clutch is provided in the gear 5 (or the gear 7 may be used) to make the feed roller 3 free to rotate in the opposite direction, and to prevent the feed roller 2 from rotating in the opposite direction. FIG. 3 shows the relationship between the drive gears of the separation roller 4 and the feed roller 3. When the gear 9 rotates in the direction of the arrow, the feed roller 3 rotates in the feeding direction (in the direction of the arrow) via the electromagnetic clutch 8. Furthermore, as the gear 9 rotates in the direction of the arrow, the separation roller 4 rotates in a direction opposite to the feeding direction via the gears 10, 11, and 12. As shown in FIG. 4, the separation roller 4 is provided at the other end of a shaft 4' that moves up and down with one side as a fulcrum, and is supported by a spring 14 and a presser member 13.
The separation roller 4 is connected to the feed roller 3 via the shaft 4'.
It is in pressure contact with the

In the embodiment configured in this way, the separation roller 4 is reversed, and the feed roller 3 is made reversely reversible outside of feeding, and even if the feed roller 3 is reversed, the feeding roller 2 is Since it does not reverse, feed roller 3
, the wear of the separation rollers 4 is small, the increase in torque due to the reversal of the separation rollers 4 is prevented, and the reverse staining of the separation rollers 4 can be prevented by an inexpensive means.

[0009]

[Effects of the Invention] As explained above, according to the present invention,
The wear of the feed roller and separation roller is small, the increase in torque due to the reversal of the separation roller is prevented, and the separation roller can be reversed using an inexpensive means to prevent back dirt.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing main parts of a double-sided paper feeding device according to the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG. 1;

FIG. 3 is a view taken along arrow D in FIG. 2;

FIG. 4 is a partially cutaway perspective view.

FIG. 5 is an explanatory diagram showing a conventional double-sided paper feeding device.

FIG. 6 is an explanatory diagram showing a conventional double-sided paper feeding device.

[Explanation of symbols]

1 Transfer paper 2. Feeding roller 2', 3' axis 3 Feed roller 4 Separation roller 5, 6, 7 gear 8 Electromagnetic clutch

Claims (2)

[Claims] Claim 1: A loading table on which one-sided copied transfer paper is loaded, a feeding roller that feeds the transfer paper stacked on the loading table from the lowest paper, and a paper feeding direction of the feeding roller. In a feeding device that includes a feed roller located downstream and a separating roller that is in pressure contact with the feed roller and rotates in a direction opposite to the paper feeding direction, the feed roller is rotatable in the feeding direction and the opposite direction, and the feeding roller is rotatable in the feeding direction and the opposite direction. A double-sided sheet feeding device characterized in that when the feed roller rotates in the sending direction, the feeding roller rotates in synchronization with the feeding direction, and when the feed roller rotates in the opposite direction, the feeding roller does not rotate. [Claim 2] A loading table on which one-sided copied transfer paper is loaded, a feeding roller that feeds the transfer paper stacked on the loading table starting from the lowest paper, and a paper feeding direction of the feeding roller. The feeding device includes a feed roller located downstream, and a separation roller that is in pressure contact with the feed roller and rotates in a direction opposite to the feeding direction of the paper, the feed roller is rotatable in the feeding direction and the opposite direction, and the feeding roller When the feed roller rotates in the feeding direction, the feed roller synchronously rotates in the feeding direction, and when the feed roller rotates in the opposite direction, the feeding roller does not rotate to feed the paper. A double-sided paper feeding method.