JPH03118560A - Image forming device - Google Patents

Abstract

PURPOSE:To equalize missing from a medium recording images of the upper- most or lower-most original image and to minimize the possibility of required information missing by providing an image forming device control means making equal the earliest and the latest image missing widths when images of plural originals are formed on the recording medium. CONSTITUTION:It is assumed that in a one-scan mode a gap between a first original S' and a second original S' is l2. A stop position is so controlled that the trailing edge of the second original S' comes to a position R2 shifted by l2/2 toward the upstream from a stop position R1 when a motor normally rotates. When an optical reading system reads the original in this position R1, the missing widths of the first and second originals S' are l2/2. When the original stop position is controlled in such a way, the missing widths of the first and second originals S' are l2/2. This missing occurs in the side of the original S where the density of picture information is low. Compared to a con ventional method which has concentrated mission of the width l2 on the first original, the possibility of original information missing becomes small.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a method for feeding a plurality of originals to an image reading position (hereinafter referred to as a platen) and forming images of the originals on the same side of the same recording medium. The present invention relates to an image forming apparatus such as a copying machine, a printing machine, a laser beam printer, or an image reader (reading device).

<Prior art> When an image forming apparatus such as a copying machine is equipped with a document feeding device and documents are automatically and continuously fed to a platen for copying,
For example, it is known to copy images of two original documents side by side on one side of a single recording medium (copy paper).

FIG. 7(a) shows an example of an image forming apparatus that performs the above-described copying.

In the figure, 100 is a main body of a copying machine, and a document feeding device 200 is installed on a platen 101 which is an image reading section.

This document feeder 200 includes a stacking tray 201 for stacking a stack of documents S, and a stack of documents S on this stacking tray 201.
A separating section 2゜2 separates the original S' one by one from
A conveyance roller 203 that conveys the
and a sensor 204 arranged between the separation unit 202 and the sensor 204 to detect the document S', and a full-surface belt 205 that sets the document S' conveyed from the conveyance roller 203 onto the platen 101.
A discharge roller 206 for discharging the document S' on the platen 101 onto a discharge tray 206 is provided.

In the above-mentioned image forming apparatus, first, a stack of originals S is set with the image side facing upward (see FIG. 1A).

Next, the separation unit 202 rotates in response to a copying process start signal, separates the lowest document S' of the document bundle S, and abuts the leading edge of the document S' against the conveyance roller 203 (see the figure). ).

Next, the conveyance roller 203 and the full-surface belt 205 are rotated in the normal direction to convey the document S' toward the platen 101, and when the trailing edge of the document S' passes through the conveyance roller 203, the conveyance roller 203 and the full-surface belt 205 are temporarily stopped. (See C).

Next, the full-surface belt 205 is reversed and stops when the trailing edge of the document S' hits the transport roller 203 (
(See figure d) # Next, the separation unit 202 is rotated to separate the two-sheet document S', and the leading edge of the document S' is brought into contact with the conveying roller 203 (see figure e).

Next, the conveying roller 203 and the full-face heald 205 are rotated in the normal direction again, and when the two-sheet document S' reaches a predetermined position on the platen 1010, the full-face belt 205 is stopped (see f in the same figure).

As a result, two documents S' are placed in parallel on the platen 101. Thereafter, when the images of the originals S' are read (see g in the same figure), the images of the two originals S' are copied onto one side of the -sheets of copy paper.

After reading, the full-surface belt 205 and the paper ejection roller 207 are rotated in the normal direction to transfer the document S' on the platen 101 to the paper ejection tray 20.
6 (see the same diagram).

<Problems to be Solved by the Invention> However, as is clear from the enlarged view of the nip portion of the conveyance roller 203 shown in FIG. It is difficult to abut the front end, and a gap corresponding to the width X of the nip portion is created.

In addition, due to component precision, it is difficult to make the conveying speed of the conveying roller 203 and the conveying speed of the full-surface belt 205 the same. It is set slightly faster than the speed. As a result, a gap is created between the documents S' set on the platen 101, which is at least as large as the width of the nip portion or larger than the gap X, which causes problems during copying. there were.

For example, as shown in FIG. 9, the size of the document S' is set to 1.
Close the gap again! , t, when copying onto copy paper that is twice the size of the original S', the -th original S' becomes 2
The area shifted by □ exceeds the image reading area, and the shaded area (!2) of the -th original S' is missing from the copy image, whereas the entire area of the second original S' is scanned. , - There is a drawback that the missing parts of the second and second sheets of the original S' are uneven.

In other words, the density of image information on a document generally increases from the periphery toward the center, so the larger the width of the gap, the more likely it is that information will be missing. When omissions occur unevenly on the side of the original document, the width of the omission is large, and there is a risk that information omissions on the -th original document are likely to occur.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and its purpose is to To provide an image forming apparatus capable of reducing the risk of information loss as much as possible by making the loss of images from a recording medium equal.

<Means for Solving the Problems> The means for solving the above problems and applied to the embodiments described below include an image information reading means for reading image information of a document, and a document being fed to a reading position of the image information reading means. In an image forming apparatus that is equipped with an original document feeding means to form images of a plurality of original documents on the same side of the same recording medium, the most downstream original and the most upstream original that are fed to the reading position are The present invention is characterized in that it is equipped with an image forming apparatus control means that equalizes the width of the missing image when reading the image information.

Here, the image forming apparatus control means includes, for example, a control means for the document feeding means that controls a document stopping position with respect to the reading position, and a control means for controlling the reading start timing of the image information reading means with respect to the document position. There are a control means for controlling the image information reading means, a control means for the conveyance means, and the like for controlling the timing at which conveyance of the recording medium is started.

According to the above means, for example, when recording the image information of two originals on the same side of a recording medium that is twice the size of the originals, the original stop position and the timing of the reading start of the image information reading means relative to the reading position can be changed. etc., so that the missing width of the first and second original images from the recording medium is equalized, thereby reducing the width of missing original images from the recording medium and improving the image information of each original. Reduces the risk of missing.

<Embodiment> An embodiment of the image forming apparatus of the present invention will be described below with reference to the drawings.

[First example]

1 to 5 show a first embodiment of the present invention,
FIG. 1 is a sectional view schematically showing a copying machine to which the present invention is applied;
Figures 2 (a) to (g) are explanatory diagrams of the operation of the document feeder section of the copying machine, Figure 3 is a block diagram of the control unit of the copying machine, and Figure 4 is a flowchart showing the control contents of the control unit. , FIG. 5 is an explanatory diagram showing the state of copying image information of a document.

In the figure, reference numeral 10 denotes a main body of the copying machine, and a document feeding device 1 as a document feeding means is placed on a platen 11 which is an image reading section.
2 is equipped.

This document feeding device 12 includes a stacking tray 13 for stacking a stack of documents S, and a separating section 14 (transport belt 14a) for separating documents S' one by one from the stack of documents S on this stacking tray 13
, separation belt 14b), a substantially U-shaped guide 15 that guides the separated document S' to the platen 11, and a guide 15 arranged at an appropriate position of the guide 15 to guide the document S' to the platen 11.
A conveyance roller 16 conveys the document S' to the platen 11.
It is equipped with a full-face heald 17 etc. that is placed in a predetermined position.

Here, on the downstream side of the stacking tray 13, a semicircular paper feed roller 18 and a sensor 19 for detecting the leading edge of the document S' are arranged.

Further, the conveyor belt 14a of the separation section 14 rotates counterclockwise in FIG. 1, and the separation belt 14b approaches the conveyor belt 14a and similarly rotates counterclockwise.

Further, a sensor 20 is arranged at an appropriate location on the guide 15 to detect the passage of the document S'.

Further, the entire surface belt 17 includes a drive roller 17a disposed on one end side of the platen 11 (on the left side in FIG.
It is composed of a driven roller 17b arranged on the other end side (right side in the figure) and a conveyor belt 17c wound around between the driving roller 17a and the driven roller 17b. One end of a drive shaft 21a of a drive motor 21 is connected to the drive shaft 17a' of the drive roller 17a, and the drive motor 21 moves the conveyor belt 17c in the direction of the solid line arrow and in the direction of the dotted line arrow shown in FIG. It is designed to run. Note that a clock plate 22 is connected to the other end of the drive shaft 21a, and a photo ink converter 23 is arranged close to this clock plate 22. This photo ink controller 23 counts the number of slits provided in the clock plate 22 to control the amount of movement of the conveyor belt 17c.

Further, on the other end side of the platen 11, a substantially U-shaped guide 23 is provided.
and a paper discharge roller 24, which discharges the document S' on the platen 11 onto a paper discharge tray 25 disposed on the conveyor belt 17a. The original S' is placed at an appropriate position on the guide 23.
A sensor 26 is arranged to detect the copying machine main body 1.
A reading optical system 27 serving as an image information reading means for reading the image of the document S' on the platen 11 is disposed inside the image forming apparatus 0 . The reading optical system 27 is composed of an exposure lamp 27a, a scanning mirror 27b, a lens 270, etc., and illuminates the document with the exposure lamp 27a while scanning with an optical scan motor 27d (see FIG. 3). The reflected light is irradiated onto a photosensitive drum (not shown) by a scanning mirror 27b and a lens 27c.

Next, feeding control of the original S' by the original feeding device 12 will be explained with reference to FIGS. 2(a) to 2(g).

Images of two originals S' are stored on one recording medium (copy paper)
When copying images side by side on one side (in one scan mode)
To do this, first rotate the feeding roller 18 and the separating section 14,
The first document S' is separated from the bottom of the document bundle S, and the leading edge of the document S' is brought into contact with the conveying roller 16 to form a predetermined loop (see FIG. 2(a)). and conveyance roller 1
6. Rotate the full-surface belt 17 in the normal direction and transfer the document S' to the platen 11.
When the rear end of the document S' passes through the conveyance roller 16, the conveyance roller 16 and the full-surface belt 17 are temporarily stopped (see FIG. 2(b)). Thereafter, the full-surface belt 17 is reversed and stops when the rear end of the document S' hits the conveyance roller 16 (see FIG. 2(C)).

Next, the feeding roller 18 and separating section 14 are rotated to separate the second document S' from the document bundle S, and the leading edge of the document S' is brought into contact with the conveying roller 16 to form a predetermined loop (
(See Figure 2(d)). Then, the conveying roller 16 and the full surface belt 7 are rotated in the normal direction again, and when the second document S' reaches a predetermined position on the platen 11, the full surface belt 17 is stopped (see FIG. 2(e)).

Here, the stop position of the full-surface belt 17, that is, the rear end stop position of the second document S' is changed from the stop position in the normal mode.

In the normal mode, the trailing edge of the document S' passes through the sensor 20 and advances by a predetermined clock so that it stops at the position R shown in FIG. 2(e) (the position where the reading optical system 27 starts reading). By the way, the full-face heald 17 stops. On the other hand, in the one scan mode, the gap between the -th original S' and the second original S' is set to 2. Then, it/it is located upstream of the stop position R1 in normal mode.
The stop position is controlled so that the rear end of the second document S' is located at the position R8, which has been moved two times (see FIG. 2(e)). As a result, the front end of the -th document S' protrudes from the image reading area by 12/2. Therefore, when reading is performed from position WR1 by the reading optical system 27, the missing width of the first original S' and the second original S' becomes 2□/2, as shown in FIG.

When the document stopping position is controlled in this way, the missing width of the first and second documents S' is 2□, as shown in FIG.
/2, but this omission is caused by the document S with low density of image information.
′ is missing at the side edge, and as in the past, the missing part is concentrated on the first page of the manuscript, and the width! The risk of missing information in the manuscript is reduced compared to the case where missing information occurs in item 2.

Next, the document S' is read (see FIG. 2(f)).
After this reading is completed, the full surface belt N7 and the paper discharge roller 24 are rotated in the normal direction to discharge the document S' on the platen 11 onto the paper discharge tray 25 (see FIG. 2 (2)).

Next, a description will be given of the control section which is the image forming apparatus control means for controlling the feeding as described above.As shown in FIG. and ROM
The control contents shown in FIG. 4 are stored in this section, and the document feeding device 12 is controlled according to the control contents.

One input terminal of the control section 30 is connected to the sensor 20.
26 and a photo ink printer 23 are connected, and signals from these sensors 20, 26 and the photo ink converter 23 are inputted to determine the size and number of originals S' on the platen 11 and the movement of the entire surface belt 17. It is designed to be calculated. The other input terminal of the control unit 30 has a mode switch 31 arranged on the operation panel (not shown) of the copying machine body 10 for setting the copy mode, and a copy size switch 31 for setting the size of copy paper as a recording medium. A switch 32 is connected.

When the mode switch 31 is set to one scan mode (a mode in which images of multiple originals S' are copied onto one side of a single sheet of copy paper), and the copy size switch 32 is set to the copy paper size, the one scan mode is set. Calculate the shift amount of the document stop position at the time.

That is, the control unit 30 calculates the shift amount of the document stop position by performing the following calculation processing based on the input signal.

[(ΣN+10Σp,)-z,]÷2 here, Σ11 is the total length of the manuscript Σ12 is the total distance between documents 13 is the length of the recording paper It is.

The drive motor 21 of the document feeder 12 is connected to the output terminal of the control system 30, and the drive motor 21 is controlled based on the calculated shift amount.

For example, if there are two originals of A4 size (length 210III11), the distance between the originals is 5111Il (a value determined by the distance between the nip portions of the transport rollers 16), so the total length of the originals is Σ2. The total length Σ12 of ten originals is 210
A2 +5 = 425 mm. At this time, the size of the copy paper is A3 (length 420 mm) and the magnification is 10.
If you specify 0χ, the shift amount is [425-(420/1.00)] ÷2 = 2.5
It becomes the torso. Therefore, when copying in this mode, the first
Copies are obtained in which the second document S' has a 2.5-minus missing portion.

In addition, when copying paper is A4 portrait and copying is done at a magnification of 50%, [425-(21010,50)] ÷2=2.5m
m, and the document stopping position is also shifted by 2.5m+++.

Next, the document feeding procedure by the control section 30 will be explained with reference to the flowchart of FIG.

First, in step S1, a stack of A4-sized documents S is set on the stacking tray 13 with the image side facing upward.

Next, in step S2, for example, one scan mode is set using the mode switch 31, and A3 size is set using the copy size switch 32.

Next, in step S3, it is determined whether there is a start signal for copy processing, and if there is a request to start copying (in the case of YES), the process moves to step S4, and it is determined whether the mode is one scan mode or normal mode. In the case of normal mode, step S5
to copy in normal copy mode.

In the case of one scan mode, the process moves to step S6 to feed the first original S', and in step S7 it is determined whether or not feeding of the first original S' has been completed. (in case of YES), the second document S is sent in step S8.
′ is fed. At this time, the second document S' is fed so that the rear end stop position of the second document S' is located at a stop position R2 shifted upstream by 12/2 from the stop position R+ in the normal mode.

Next, in step S9, it is determined whether or not feeding of the second document S' has been completed, and if it has been completed (in the case of YES), the document S' is read in step SIO. At this time, the images of the two originals S' are copied on one side of the A3 copy paper with the same width of deletion (see FIG. 5).

After the reading is completed, the document S' is ejected onto the paper output tray 25 in step 311, and it is determined in step 312 whether or not the document S' remains on the stacking tray 13, and if it remains (in case of YES) ), the process returns to step S6 and the document S'
Repeat the same operation until there are no more.

[Second example]

In the first embodiment, the document stop position R2 is shifted upstream by 2□/2 with respect to the reading position R1 so that the missing widths of the first document S' and the second document S' are equal. However, in this second embodiment, the document stopping position is the same as in the normal mode, but the reading optical system 27 starts reading. The position is shifted downstream by 22/2 as shown in FIG. 2(e).

That is, when the rear end of the second document S' reaches a predetermined position on the platen 11, the entire surface belt 17 is stopped.

This predetermined position is the same as the stop position in the normal mode.
It's the location. Then, the reading optical system 27 starts scanning and reads the document, but at this time, the optical scan motor 2
7d (see FIG. 3) is controlled by the control unit 30 to shift the reading start position by 2□/2 downstream from the reading start value ylRI in the normal mode or Book mode. Change to R3.

As a result, the missing widths of the first original S' and the second original S' become equal, as in the case of the first embodiment.

[Third Example]

In the first embodiment, the document stop position R2 is shifted upstream by 42 t/2 with respect to the reading position R1, and in the second embodiment, the reading start position is shifted 2 t/2 downstream from the reading position R1 in the normal mode. The gap width of the first document S' and the second document S' are made equal by shifting by □/2, but the document stop position and reading start position are the same as in the normal mode, at position R1. The control unit 30 controls the timing at which the registration clutch 33 of the recording paper conveyance system is driven.
The same effect can be obtained by slowing down by 12/2.

That is, as shown in FIG. 6, the transfer timing of the first image information 34a+, the second image information 34a2, and the recording paper 35 of the photoreceptor drum 34 is controlled by the control unit 30 by controlling the resist clutch 33, and the distance 2 is adjusted. By slowing down by □/2 (by starting conveying the recording paper 35 late)
, it becomes possible to make the missing widths of the -th original S' and the second original S' equal.

Note that the first image information 34a+ on the photoreceptor drum 34.

The shift amount of the second image concession 34a2 and the recording paper 35 is when making a full size copy! Although it is 2/2, in case of variable size copying, it becomes (zz /2)x magnification. This is photosensitive drum 3
This is because the image information 34a on 4 is an image that has already been scaled, so it is necessary to apply a magnification to the shift amount of the recording paper 35 as well.

[Other Examples]

In the embodiment described above, the stacking tray 1 is used as the document feeder 12.
Although a type of device is shown in which a document S 3 and a discharge tray 25 are provided separately, a device of a type in which the fed document S' is returned to the stacking tray 13 may also be used.

Further, although the case where two originals S' are fed onto the platen 11 and copied is shown, three, four, etc. originals S' may be fed onto the platen 11 and copied.

Furthermore, when forming images of multiple originals S' on the same side of the same recording medium, we have shown the case where they are formed only on one side (front side) of the recording medium (in the case of single-sided copying), but the recording medium is not stored inside the printer. It can also be applied to double-sided copying in which the front and back sides are reversed and images of a plurality of documents S' are formed on the back side as well.

Further, although the case where this embodiment is applied to a copying machine has been shown, it goes without saying that it can also be applied to a laser beam printer, an image league (reading device), and the like.

<Effects of the Invention> As described above, according to the present invention, when forming images of a plurality of originals on the recording medium, an image forming apparatus control means is provided that makes the width of the image loss at the most upstream and the most downstream equal. Since this is installed, the most upstream and most downstream original images are equally missing from the recording medium, and the risk of information loss can be minimized.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a sectional view schematically showing a copying machine, and FIGS. 2(a) to (
g) is an explanatory diagram of the operation of the document feeder section of the same copying machine, No. 3
Figure 4 is a block diagram of the control unit of the copying machine, Figure 4 is a flowchart showing the control contents of the control unit, Figure 5 is an explanatory diagram showing the copying state, and Figure 6 is another embodiment. (
7(a) to (h), FIG. 8, and FIG. 9 show the prior art,
FIG. 7(a) is a schematic cross-sectional view, FIGS. 7(b) to (h) are explanatory diagrams of the operation, FIG. 8 is an enlarged cross-sectional view of the nip portion of the conveyance roller, and FIG. 9 is a diagram showing how image information is transferred from the recording medium. It is an explanatory diagram showing a missing state. 10 is the copying machine body, 11 is the platen (image reading position),
12 is a document feeding means (document feeding device), 13 is a TL tray, 14 is a separation section, 16 is a conveyance roller, 17 is a full-face heald, 18 is a paper feed roller, 19.20 is a sensor, and 21 is a Hf+jt-1. 22 is a clock + counter, 23 is a photointerrupter, 27 is an image information reading means (reading optical system), 27d is an optical scan motor, 30 is an image forming apparatus control means (control unit), 33 is a resistor, 7 chips , S
′ is the manuscript.

Claims (4)

[Claims] (1) Image information reading means for reading image information of a document;
An image forming apparatus for forming images of a plurality of originals on the same side of the same recording medium, which is equipped with a document feeding means for feeding a document to a reading position of the image information reading means, An image forming apparatus characterized in that it is equipped with an image forming apparatus control means that equalizes the gap width when reading image information of the most downstream original and the most upstream original that have been sent. (2) The image forming apparatus according to claim 1, wherein the image forming apparatus control means is a control means for the document feeding means that controls a document stopping position relative to the reading position. (3) The image forming apparatus control means is a control means for an image information reading means that controls the timing at which the image information reading means starts reading with respect to the document position. Image forming device. (4) The image forming apparatus according to claim 1, wherein the image forming apparatus control means is a control means for a conveyance means that controls a timing at which conveyance of the recording medium is started.