JP2594390B2 - How to adjust the position of the copied image - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for adjusting the position of a copy image on both sides of a copy sheet, obtained by a double-side copy method.

[0002]

2. Description of the Related Art In general, in a two-sided copying method, first, an original sheet is placed on an original placing table, and a character image drawn on the original sheet is exposed to form a first copy sheet. A copy image such as a toner image corresponding to the character image is formed on one side, for example, the front side, and then, when the original sheet is a double-sided original, that is, one original sheet and both front and back sides If a different type of character image is drawn on the original sheet, turn this original sheet over, and if it is a single-sided original sheet, place another original sheet on the original placing table. Exposure is similarly performed to form different types of character images on the second side of the copy sheet, that is, on the back side, thereby obtaining a double-sided copy.

[0003]

[SUMMARY OF THE INVENTION However, in the method described above, it is possible to obtain a copy of which is formed on both sides of the transfer sheet, the transferred images position i.e. the effective image formation on the copy sheet There is a problem that the positions of the regions are shifted from each other.

That is, the transfer images transferred to the copy sheet are displaced from each other when viewed from one direction, so that the binding margins on both sides of the copy sheet cannot be aligned in one direction, and this type of copy sheet is formed into a large number of sheets. It was difficult to bind children across.

[0005]

Therefore, in the present invention, a copy sheet sent to a photoreceptor is reversibly conveyed by a copy sheet reversing means after transfer, and the conveyed sheet on which the front side is copied. Is transferred to a storage table provided in the reverse transport direction, and thereafter, the copy sheet is re-fed from the storage table to the photoreceptor by the re-feeding means to transfer the back surface of the copy sheet. In the double-sided copying method, the positional deviation of each copy image on the front and back sides of the copy sheet is corrected, and the copy image on the front side and the copy image on the back side of the copy sheet are changed to one of the reference sides. The position of the lens constituting the exposure optical system for forming an intermediate copy image on the photoreceptor is changed in accordance with the positional deviation amount and the direction when copying one of the front and rear surfaces. I did it.

[0006]

[Action] than was be changed according to the mutual shift amount of each copy image of both sides of the copy sheet the optical position of the exposure optical system for forming an intermediate copy image on a photosensitive member, formed on the photoreceptor The position of the intermediate copy image to be transferred is formed at a position corresponding to the deviation, and the position of the transfer image transferred to each surface of the transfer sheet coincides.

[0007]

Embodiments of the present invention will be described below. This embodiment by changing the optical position of the exposure optical system, multiple
This is to adjust the positions of the transfer images formed on both sides of the copying sheet. In FIG. 1, reference numeral 9 denotes a copying apparatus of a double-sided copying system, and an original sheet S2 as shown in FIG. The effective image forming area S2 on one side of the original sheet S2
In a, a character image as shown in the figure is drawn, and
A binding margin having a width L1 is formed at one end of the sheet S2, and a slight margin portion having a width L2 is formed at the other end.

In this manner, the document sheet is rotated counterclockwise as viewed from the right side in FIG. 3 and placed on a document table 10 (as viewed in the direction of arrow A in FIG. 1) as shown in FIG. When a single-sided original sheet having L1 and L2 is copied on both sides of a copy sheet S0, an image (L1-L) transferred to one side and the other side as shown in FIG.
2) Minute shift occurs.

As shown in FIG. 1, the copy sheet S0 is fed from the main paper feed table 20 to the drum-shaped photoconductor 11 through the main paper feed path 22 by the action of the main paper feed roller 21. Has become.

On the peripheral surface of the photoreceptor 11, a character image of a document sheet S2 placed on a document placing table 10 is moved at a speed ratio of 1: 1/2. Exposure optical system 13 including lens 16, reflecting mirror 17, etc.
And an electrostatic latent image as an intermediate copy image is formed on the peripheral surface of the photoconductor 11. In addition, the in-mirror lens 16
Indicates that when a character image of another document sheet S3 shown in FIG. 4 is formed on the photosensitive member 11 by a moving mechanism (not shown) (L1-L
2) It moves downward by / 2. The formed electrostatic latent image is visualized as a toner image, for example, by the developing device 18, and the visible image is transferred onto the copy sheet S <b> 0 sent out toward the photoreceptor 11 and fixed. The toner is fixed on the sheet by passing through the roller pair 23.

In the vicinity of the fixing roller 23, the copy sheet S0
A copy sheet reversing means 30 is disposed in the direction of travel of the original sheet S2.
4 once. That is, copying Sea <br/> bets S0 which is reverse conveyance after the character image has been transferred to one side of the copy sheet (surface of the table), the intermediate feed table is an example of a receiving table provided in the reverse conveyance direction 24, and the transfer of the document sheet S0 to the front surface is completed. In other words, the copy sheet S0 placed on the intermediate sheet feeder 24 is held as shown in the lower right part of FIG. 3, but in this state, the character image of the original sheet S2 is displayed on the front side of the copy sheet S0. Is obtained.

Next, the transfer to the back surface of the original sheet S0 will be described. An intermediate paper feed roller 25 for feeding the copy sheet S0 is installed on the intermediate paper feed table 24 so as to be driven to rotate counterclockwise in the figure.
Thus, the copy sheet S0 that has been transferred to the front surface is conveyed toward the drum 11 via the intermediate paper feed path 26.

When another original sheet S3 shown in FIG. 4 is placed at a predetermined position on the original placing table 10, there is a deviation (L1-L2) from the character image of the first original sheet S2. Therefore, in order to make the copy images on both sides of the copy sheet coincide with each other, for example, as shown in FIG. 5, the copy image on one side may be shifted in the direction of arrow B by (L1-L2). That is, the transfer image may be shifted by (L1−L2). In the case of the present embodiment, the in-mirror lens 16 shown in FIG. (L1−L2), the electrostatic latent image formed on the photoconductor 11 may be formed earlier than the first transfer.

That is, as shown by a two-dot chain line in FIG. 1, the character image of the second original sheet S3 on the original table is (L1
−L2), the image forming range is shifted from the original sheet S2, so that the variable reflecting mirror 1 serving as the scanning system of the exposure optical system 13
The optical path of the document sheet S3 scanned by the scanners 4 and 15 moves to the two-dot chain line by moving the in-mirror lens 16 to the position of the virtual line below by (L1−L2) / 2, and relatively on the document sheet. Is shifted by (L1-L2). Then, the position of the electrostatic latent image formed on the photoconductor 11 is formed to be shifted by (L1−L2),
A so-called toner image visualized by the developing device 18 is transferred to the copy sheet S0 conveyed to the drum 11 via the intermediate paper feed path 26, and the sheet is fixed to the fixing roller pair 23 and The sheet is discharged to a sheet discharge table 28 via a sheet discharge path 27. Therefore, the copied images formed on both sides of the original sheet coincide.

In this case, only the in-mirror lens 16 is displaced as described above without changing the document sheet feeding start timing.

By the way, the character image portions or binding portions of the original sheets S2 and S3 shown in FIGS. 3 and 4, respectively, are not at fixed positions but are different for each sheet. For example, even if the binding width is taken, there is some error in the width dimension. Therefore, the shift amount (L1−L2) may change each time, and may be arbitrarily and selectively changed according to the shift amount at which the in-mirror lens 16 changes.

As described above, the two-sided copy image can be matched and the binding margin can be aligned in one direction. The original sheet used at this time has the character image portion orientation shown in FIGS. As shown in FIG. 2, it is parallel to the axial direction of the photosensitive drum 11, and in other words, the character image portion is located in a direction perpendicular to the exposure scanning direction of the movable reflecting mirrors 14, 15, for example. Will be. In other words, the original sheets are placed vertically, but there are also other original sheets that are placed horizontally, such as A4 size original sheets. In this case, the character image orientation of the original sheet is parallel to the above-described exposure scanning direction. Even when such a landscape document sheet is used, the two-sided copy images may not match.

That is, in FIG. 6, the first original sheet S
4 is placed on the document table 10 as shown in FIG. Then, through the above-described copying process, the copy sheet S
On one side of 0, a copy image for the character image of the original sheet S4 is obtained. This time, as shown in FIG. 7, when the copying is performed in the same manner using the second original sheet S5, the character image of the second original sheet S5 is placed on the other side of the copy sheet S0. Is obtained.

It is important to note that the position of the copy sheet shown at the lower right of FIG.
It needs to be flipped by 80 degrees. If this is not done, the top and bottom positions of the duplicate images on both sides will be reversed. Therefore, in this case, the intermediate sheet feeding table 24 in FIG. 1 may be set at a position inverted by 180 degrees.

Returning to FIG. 7, a copy image corresponding to the character image of the double-sided original sheet is obtained on both sides of the copy sheet S0 as shown at the lower right in FIG. Positions do not match each other. Therefore double
If the copy image on one side of the copy sheet S0 (the copy image on the front side in the figure) is shifted by the shift amount (L1-L2) in the direction of arrow D, the two copy images match, and the binding allowance is also reduced. Aligned in one direction. In this case, a lens system such as an in-mirror lens in the exposure optical system may be selectively moved in the drum axis direction according to the shift amount.

FIG. 8 shows the transfer process when the position of the original sheet is reversed.
When compared with the above, the state of the character image of two original sheets (see FIG. 3 for one original sheet) is inverted. Normally, this type of mounting method is also possible when copying is performed. In this case, in order to match the two-sided copied images, the copied image on one side of the copy sheet S0, that is, the copied image on the front side in FIG. In the G direction (L1-L2)
Only need to be moved. Therefore, in this case, the in-mirror lens 16 shown in FIG. 1 may be moved upward according to the shift amount.

[0022]

According to the present invention, the two-sided copy images can be made to correspond to each other only by displacing the exposure optical system, and the binding margin can be aligned in one direction. In addition, bookbinding becomes possible, so that character images of documents can be read easily, and scattering can be prevented. In addition,
The present invention can be applied to a normal one-sided copying system for the purpose of aligning the binding margin in one direction.

[Brief description of the drawings]

FIG. 1 is a side view of a double-sided copying apparatus in which an in-mirror lens in an exposure optical system that is a main part of the present invention is moved.

FIG. 2 is a plan view showing a document placing section of the duplex copying apparatus.

FIG. 3 is a diagram illustrating an example of a transfer process performed by the duplex copying apparatus.

FIG. 4 is a diagram illustrating an example of a transfer process performed by the duplex copying apparatus.

FIG. 5 is a view for explaining a matching method for matching copied images on both sides of a copy sheet with each other.

FIG. 6 is a diagram illustrating an example of a transfer process when a document sheet is placed horizontally.

FIG. 7 is a diagram illustrating an example of a transfer process when a document sheet is placed horizontally.

FIG. 8 is a diagram illustrating an example of a transfer process when a document sheet mounting direction is changed.

[Description of Signs] 11 Photoconductor 13 Exposure optical system 16 Lens (in-mirror lens) 24 Housing (intermediate paper feed table) 25 Re-feeding means (intermediate paper feed roller) 30 Copy sheet reversing means S0 Copy sheet S2 to S5 Manuscript sheet sheet

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuhiro Tabata 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd. (72) Inventor Tamaki Kaneko 1-3-6 Nakamagome, Ota-ku, Tokyo (56) References JP-A-49-91453 (JP, A) JP-A-47-10032 (JP, A)

Claims (1)

(57) [Claims] 1. A copy sheet which is fed to a photoreceptor is reversely conveyed by a copy sheet reversing means after transfer, and the conveyed sheet having the front side copied is provided in a reversing conveyance direction. Then, in the transfer type double-sided copying method in which the copy sheet is re-fed from the storage table to the photosensitive member by the re-feeding means to transfer the back side of the copy sheet, In order to align the copy image on the front side and the copy image on the back side of the copy sheet with one of the reference sides by correcting the mutual displacement of When copying one,
A position adjustment method of a copy image, wherein an installation position of a lens constituting an exposure optical system for forming an intermediate copy image on the photoconductor is changed according to the amount of the positional shift and its direction.