JPS6213661B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic double-sided copying device, and more particularly to a double-sided copying device that faithfully reproduces the front and back relationships of pages of books and the like.

The following types of conventional double-sided copying devices have been considered. First, as disclosed in Japanese Patent Publication No. 42-4392, ordinary one-sided copying is first performed on one side of the transfer material, and after the one-sided copying is completed, the transfer material is folded back at the image transfer station and used again. The paper is guided to a paper feeding device or another paper feeding device, and sent again to a transfer station to make a copy on the back side, thereby making a double-sided copy. In this format, the operator has to turn over the original image each time a single-sided copy is made, so if a large number of double-sided copies are to be obtained, the operator must turn over the original image each time one double-sided copy is obtained, which is a cumbersome task.
This wasted time.

Secondly, as disclosed in Japanese Patent Publication No. 50-33665 in order to eliminate the above-mentioned drawbacks, normal one-sided copying is first performed on one side of the transfer material, and after the one-sided copying is completed, the transfer material is transferred to another. The transfer material is guided to the paper feeder and stacked therein, and the paper feed roller provided on the paper feeder feeds the transfer material again to the same transfer station in the reverse order of stacking to make a copy on the back side. This is a form in which you can obtain a copy. According to this format, since another paper output tray and paper feed device is used, 1
There is no need to make double-sided copies each time, and since it is a format in which a large number of single-sided copies are made first, and then copies are made to the other side to obtain double-sided copies, when a large number of copies of the same page are to be made, it is possible to It is possible to eliminate the work of exchanging or turning over the original image each time.

However, in the second type of double-sided copying device, the order of the first one-sided copying and the second copying on the other side are completely reversed, making it difficult to correctly form the front-back relationship of the original onto the copy material. If you do not adopt the above-mentioned format, which makes multiple copies of multiple pages of the original image all at once on one side, change the copying process to double-sided mode operation every time the page of the original image changes. have to,
The operator still wastes time on operations. Furthermore, if the transfer material is reversed within the apparatus in order to unify the page order, there is a drawback that the apparatus becomes bulky and complicated.

The present invention eliminates these drawbacks and provides a double-sided copying device that faithfully reproduces the front and back relationship between the front and back pages of an original image of a book, etc., and also provides an efficient and inexpensive copying device that eliminates unnecessary work. be.

First, an example of a copying apparatus to which the present invention is applied will be described. In FIG. 1, a photosensitive drum 1 is uniformly charged by a corona charger 2, and an exposure lamp 3 illuminates a document 6 on a transparent document table 5 provided on the upper surface of the apparatus main body 4, and the light is emitted from the photosensitive drum 1. A first reflecting mirror 7 and a second reflecting mirror move the images at a speed difference of 1:1/2.
Reflector 8, in-mirror lens 9, fixed reflector 1
0 to form an electrostatic latent image on the photosensitive drum. The electrostatic latent image is developed by a developing device 11. As the developing device, a magnetic brush developing device having a magnet inside the non-magnetic sleeve 12 is used. The developed toner image is transferred to a paper feed tray 1 serving as a first transfer material storage means that stores the transfer material P.
3 is brought into contact with the transfer material P fed by a paper feeding roller 14 as a paper feeding means, and a corona transfer charger 15 to which a voltage of a polarity different from that of the toner is applied is applied onto the transfer material P. transcribed into. After the transfer material P is separated from the photosensitive drum 1, a toner image is permanently fixed thereon by a fixing roller 16, and the transfer material P is loaded onto a paper discharge tray 17 serving as a second transfer material storage means. On the other hand, after the transfer, the toner remaining on the photosensitive drum 1 is neutralized by a corona static eliminator 18 to which polarity opposite to that of the toner or AC voltage is applied, in order to facilitate removal from the photosensitive drum 1. Next, all residual toner is removed from the photosensitive drum 1 by a cleaning blade 19.

The above is a copying operation for normal one-sided copying, but next, a double-sided copying operation will be explained. In FIG. 1, the transfer materials P whose one side has been copied are stacked on the paper discharge tray 17 with the image-formed side facing upward in the order in which they were fed from the paper feed tray 13 from bottom to top. This paper output tray 17
can be attached to the rear of the paper feed tray 13 as shown in FIG. The transfer material P loaded on the paper discharge tray 17 after single-sided copying is mounted to the rear of the paper feed tray 13 while being placed on the paper discharge tray 17 . After loading, the transfer material P in the paper discharge tray 17 is moved by the feeding roller 20 as a feeding means.
are stacked one by one into the front paper feed tray 13 from above. At this time, the paper feed roller 14 is kept sufficiently spaced from the paper feed tray 13 so as not to interfere with the conveyance of the transfer material fed from the rear. It goes without saying that the paper discharge tray 17 has a structure that not only serves as a tray but also serves as a paper feeder. The transfer materials in the paper feed tray 13 sent from the paper discharge tray 17 are stacked in the opposite order to the order in which they were stacked on the paper discharge tray 17 with the image-formed side facing up. Therefore, the order in which the transfer materials P are fed from the paper feed tray 13 to the transfer position by the paper feed roller 14 is exactly the same as in the case of the initial one-sided copying. As a result, the image already formed on one side of the transfer material can be reliably matched with the corresponding image, and the double-sided copying operation can be switched only once. The transfer material P fed from the paper feed tray 13 has a toner image transferred to the other side by the transfer charger 15 and fixed, and is then discharged to the paper discharge tray 17A to complete the double-sided copying operation. It goes without saying that a tray having the same structure as the paper discharge tray 17 can be used as the paper discharge tray 17A.

The double-sided copying apparatus according to the present invention can be very conveniently implemented in an apparatus equipped with an automatic sheet document feeding apparatus as shown in FIG. According to FIG. 3, sheet-like originals A, B, and C are stacked in order from the top on the original paper feed tray 21, and the paper feed roller 22
Dispense from top to bottom. Original paper feed tray 21
The sheet-like original A fed from is conveyed by a pair of guide rollers 23, 23, passes through an original illumination section 24, and is then conveyed by a pair of guide rollers 23 at the rear.
5 and 25, and is discharged onto the document discharge tray 26. The exposed original is A′, B′,
They are stacked in the order of C′. Next, when copying the other side, the entire sheet document on the document output tray 26 is reversed and transferred to the document feed tray 21.
If it is attached to the top, the sheet-like originals will be stacked in the order of A', B', and C' from the top. Then, when the next copying operation begins, the paper feed roller 22
A sheet-like original document A' is fed, and the back side which has not been exposed previously is exposed by the exposure section 24, and this process is repeated thereafter to complete the double-sided copying operation. Note that when a plurality of copies of one page are to be made, one sheet-like original may be repeatedly passed through the exposure section 24 using a repeating device (not shown).

A copying method for obtaining a plurality of copies from each page of a plurality of pages of a manuscript will be described in detail with reference to FIG. That is, Figure 4 consists of an 8-page manuscript, with 1-2 pages and 3 pages on each side of one sheet of paper.
This explains the case where there are 4 pages, 5-6 pages, and 7-8 pages, and two copies are obtained from each page.

FIG. 4a shows the order in which the transfer materials P stored in the paper feed tray 13 in FIG. 1 are stacked.
Now place the first page of the original 6 on the original table 5, set the repeat dial to "2", and press the print button (not shown). Then, the copying operation is repeated only for the third page, the fifth page, and the odd numbered pages. The transfer material P, on which only odd numbered pages have been copied on one side, is transferred to the paper output tray 17 as shown in Fig. 4b.
They are loaded in the order shown. The numbers inside the brackets on the transfer material P indicate the copied pages. Next, the transfer material P, which has been copied on one side as described above, is set at the position shown in FIG. The stacking order of the transfer materials P in the paper feed tray 13 before being re-fed to the transfer position is as shown in FIG. 4c. After one-sided copying is completed, preparations for the next copying operation are made by switching the copy mode to double-sided mode. Next, the second page of the original is placed on the original table 5, a print button (not shown) is pressed, and the fourth page, the sixth page, and even numbered pages are placed on the document table 5 and the copying operation is repeated. After the double-sided copying operation is completed, the transfer material P is stacked on the paper discharge tray 17' as shown in FIG. 4d and discharged. That is, the transfer materials P are in the order of the first, second, and eighth sheets from the bottom, and the first and second sheets each have the first page of the original on one side and the second page of the original on the other side. The third and fourth sheets are the third and fourth pages of the manuscript, and the fifth and sixth sheets are the fifth and sixth pages of the manuscript.
For the seventh and eighth pages, the seventh and eighth pages of the manuscript are copied on both sides of each transfer material, respectively.

The present invention eliminates the above-mentioned drawbacks by having the above-described configuration. That is, compared to a normal single-sided copying device, the number of copies is half, so the weight is half, and it is also economical.
In addition, even when duplexing continuous pages of a document, the duplex mode can be switched only once, so the operation is simple and copying can be carried out without waste. Furthermore, since the order in which the transfer materials are fed during one-sided copying is the same as the order in which the transfer materials are fed during the second copying on the other side, the duplex copying operation is further simplified, and the front and back sides of one sheet of transfer material are It is possible to accurately copy the front and back relationships of a single page of a document. Furthermore, in the present invention, it is possible to arbitrarily select between normal one-sided copying and double-sided copying. Moreover, the present invention
Since the position of the paper ejection tray is simply changed, it is possible to provide a small-sized copying machine with a simple structure, and it is possible to constantly check the copying state of the ejected transfer material.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an electrophotographic copying machine showing an embodiment of the present invention, and FIG. 2 is a partial cross-sectional view of the apparatus of the present invention when a paper discharge tray is installed behind the paper feed tray.
FIG. 3 is a partial cross-sectional view of an automatic document feeder that can be suitably implemented in the present invention, FIG. 4a shows the loading order of transfer materials stored in the paper feed tray, and FIG. Figure 4c shows the order in which the transfer materials are fed during double-sided copying, and Figure 4d shows the order in which the transfer materials are stacked on the paper output tray after double-sided copying is completed. It is something that DESCRIPTION OF SYMBOLS 1... Photosensitive drum, 6... Document, 13... Paper feed tray, 14... Paper feed roller, 15... Corona transfer charger, 17... Paper discharge tray, 20... Feed roller, 2
3, 25...Guide roller, 24...Document illumination section.

Claims (1)

[Claims] 1 a first transfer material storage means for storing the transfer material;
a paper feeding means for feeding one sheet of the transfer material loaded in the first transfer material storage means; a transfer means for forming a toner image on the first surface of the fed transfer material; A second transfer material storage means is detachably attached to the main body of the apparatus, and the transfer material fed from the transfer material storage means is reversed and stacked during conveyance. A mounting means installed at the rear of the transfer material storage means, and a mounting means installed at the rear of the transfer material storage means, and a mounting means installed at the rear of the transfer material storage means, and the transfer material stored in the second transfer material storage means are fed to the first transfer material storage means in the reverse order of feeding from the first transfer material storage means. feeding means for feeding the transfer material to the first transfer material storage means, and directing the transfer material re-stored in the first transfer material storage means toward the transfer means in order to form a toner image on a second surface thereof. A double-sided copying device characterized by: