JPH0416961A - Automatic both-side copying device - Google Patents

Abstract

PURPOSE:To improve productivity in the case of both-side copying and to make a device easily comply with paper jamming when it occurs by setting a counted value set in a timer by a timing setting part as a value that a copying paper to which copying on a 1st side has been executed reaches an inversion and transfer part after the copying paper to which copying on both sides has been executed is ejected from a final ejection port. CONSTITUTION:The counting of the timer 120 is started in timing that the last copying paper in the inversion and transfer part is fed, and a paper feeding roller for feeding a blank paper is driven by a paper feeding roller control means 116 when the timer 120 counts up. In such a case, the counted value set in the timer 120 by the timing setting part 111 is set as the value that the copying paper to which copying on the 1st side has been executed reaches the inversion and transfer part 80 after the copying paper to which copying on both sides has been executed is ejected from the final ejection port. Thus, the productivity in the case of both-side copying is improved and the device easily complies with the paper jamming even when it occurs at the final ejection port.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improving the production efficiency of an automatic duplex copying apparatus that reads both sides of a document and copies both sides of copy paper.

(Background of the Invention) There is an automatic reversing document feeder (hereinafter referred to as RADF) as a device for copying both sides of a double-sided document by automatically inverting the document as soon as it is set. Using such a device, large quantities of copies can be easily made. Furthermore, since the copies are in the same order as the original, there is no need to rearrange them after copying.

Furthermore, by linking it with a sorter, collation and page sorting can be performed automatically, making it possible to accurately arrange a large number of copies.

In addition, the ADT is a device that can automatically copy both sides of copy paper (hereinafter referred to as copy paper) by pressing a button.
There is a J. By using this function, information from two pages of a document can be combined on one sheet, making it possible to save on copy paper costs and at the same time making filing easier. It can also be used in a variety of ways, such as organizing materials into a booklet format for easy viewing.

By the way, when double-sided copying is performed using a conventional automatic duplex copying device, after the last copy sheet for copying on the second side (the copy sheet on which both sides have been copied) is detected to be ejected by the ejection detection means in the paper ejection unit. , copy paper (blank paper) was sent out from the paper feed unit for copying the first side of the next original.

This is to make it easier to remove the jammed copy paper when a paper jam occurs, and to reduce paper waste.

(Problems to be Solved by the Invention) In the conventional automatic duplex copying apparatus configured as described above,
2nd side copy The time from when the last copy paper is completely ejected until the copy paper (blank paper) for the next copy is fed from the paper feeder to the photoreceptor. was wasted.

In particular, when a sorter is used, the paper path to the final ejection port is long, and it takes some time for the copy paper to be finally ejected. Furthermore, it takes time for the blank paper from the paper feeding section to reach the photoreceptor.

Therefore, there is a problem in that it takes too much time from the end of copying the second side of one document to the start of copying the first side of the next original, resulting in a decrease in productivity.

Furthermore, if the next copy paper is fed before the paper that has been copied is finally ejected, the process when a jam occurs becomes extremely troublesome.

The present invention has been made to solve the above-mentioned problems, and its purpose is to shorten the time from the end of copying the second side to the start of copying the first side of the next original, thereby reducing the time required for double-sided copying. It is an object of the present invention to realize an automatic double-sided copying device that can improve productivity and can easily deal with the occurrence of a jam.

(Means for Solving the Problems) The present invention, which solves the above-mentioned problems, reverses the copy paper on which the first side has been copied by a reversing transfer unit, and transfers the second side of the copy paper sent out from the reversing transfer unit to In an automatic double-sided copying device that performs copying, there is a timer that counts according to a set count value, and a timer that sets the count value in the timer and starts counting the timer at the timing when the last copy paper is sent out from the reverse transfer unit. It is equipped with a timing control unit for starting the timer, and a paper feed roller control unit for driving a paper feed roller to send out blank paper when the timer counts up. After the last copy sheet sent out from the printer passes through the registration rollers and before final ejection, the blank paper from the main body's paper feed section is fed by the paper feed rollers just before the registration rollers, and both sides are copied. It is characterized in that the value is such that the copy paper whose first side has been copied reaches the reversal transfer section after the copy paper whose first side has been copied is discharged from the final discharge port.

(Function) In the automatic double-sided copying apparatus of the present invention, a predetermined count value is set in the timer by the timing control means, and counting of the timer is started at the timing when the last copy sheet is sent out from the reversing transfer section. When the timer counts up, the paper feed roller control means drives the paper feed roller for sending out the blank paper.

As a result, after the last copy sheet sent out from the reversing transfer section passes through the registration rollers and before the final ejection, the copy paper from the main body paper feed section is fed by the paper feed rollers just before the registration rollers. be done. Then, the copy paper fed in this manner reaches the reversal transfer section after the first side has been copied and the last copy paper on which double-sided copying has been completed is finally discharged.

(Example) Examples of the present invention will be described in detail below with reference to the drawings.

First, the general operation of the electrophotographic copying apparatus to which the present invention is applied will be explained with reference to FIG.

In Figure 3, the automatic double-sided document feeder (hereinafter referred to as RAD)
A document 1 placed on a 10 (referred to as F) is moved onto a platen glass 2 by the RADF 10 at the start of copying. The original 1 placed on the platen glass 2 is exposed by the scanning exposure optical system 20, and a latent image corresponding to the original 1 is formed on the surface of the photoreceptor 30. This latent image is formed into a toner image on the surface of the photoreceptor 300 by the photoreceptor image forming section 3 . The toner image is transferred to a copy paper feeding section 40, which will be described later.
The toner image is transferred onto copy paper 41 supplied from the toner image, and the transferred toner image is heated and fixed in a fixing device 50. The copy paper on which the first copy has been completed in this manner is led to an inversion transfer unit (hereinafter referred to as ADU) 80 by the paper discharge switching unit 70 and is inverted. Then, copying (formation of a toner image) on the second side of the copy paper is performed.

After this toner image is fixed, the sheets are guided to a sorter 90 by a sheet discharge switching section 70, and are discharged outside the machine in a sorted state at a final discharge port 91.

Next, FIG. 1 shows the electrical configuration of the device of this embodiment.

Figure 3 above and Figure 2 showing the flow of operation of the device of this embodiment
The operating state of this embodiment will be explained step by step along the copy paper feeding process with reference to the drawings and FIG. 4.

First, set the number of copies 1. Copy paper size, variable magnification amount.

The final discharge position and other modes are set from an operation setting section (not shown) (step 2). Based on this configuration,
The timer 120 is set. The settings of this timer 120 will be described in detail later.

When an original is set on the RADF 10 and the copy button is pressed, copying starts (step ■).

As described above, the copy paper 41 is supplied to the photoreceptor 30 from the copy paper feed section 40 (step (2)).

The copy paper feed section 40 is provided with three paper feed cassettes 42a to 42c that store, for example, three types of copy paper 41a to 41c of different sizes.

Copy paper 4 ], a to 41c are paper feed cassettes 42a to
From 42c to delivery rollers 43a to 43c and delivery heald 44
a to 44c. Delivery roller 43a
-43c, delivery belts 44a-44c are stretched, and either the delivery belts 44a-44c or the copy paper 41a-43c are stretched.
By rotating the delivery rollers 43a to 43c clockwise (FIG. 3) while in contact with the copy paper 41C, the uppermost copy sheets 41a to 41c are delivered one by one to the left in FIG.

Copy paper 41a sent out by sending out bell) 44a to 44c
~4 Lc is the paper feed roller 61 and the registration roller 6
2 and transported to position P2 (FIG. 3). From position P2, the toner image is sent out by the registration rollers 62 after being synchronized with the rotation of the photoreceptor 30, and the toner image is transferred from the surface of the photoreceptor 30 (step (2)).

In the case of one-sided copying, the image is then heated and fixed in the fixing device 50,
Copying is completed when the paper is discharged from the paper discharge switching section 70 to the outside of the machine by the sorter 90.

In the case of double-sided copying, the copy sheets stacked in the ADU 80 are re-fed (step 2) as described below.

Downstream of the fixing device 50, there is a function for switching between a paper discharge path 76 that allows the copy paper 41 after fixing to proceed straight and is ejected to the sorter 90 side, and an introduction path 77 that transports the copy paper 41 to the guide plate 7 for double-sided copying. A paper discharge switching section 70 is also provided. The paper discharge switching section 70 has a kite plate 71. Upstream roller 72. The downstream roller 73 is composed of a movable branch body 75 having an inverted triangular cross section that swings about the shaft 74, an electromagnetic solenoid (not shown), and the like. A movable branch body 75 having an inverted triangular cross section allows a paper discharge path 7 along the upper surface of the movable branch body 75 to be
6. An introduction path 77 communicating with the guide plate 71 along the lower right side, and a guide plate 71 and downstream roller 73 along the lower left side.
A reverse paper ejection path 78 communicating with the two is formed respectively.

The movable branch body 75 is driven by a drive device (not shown) such as an electromagnetic solenoid, so that the right tip moves up and down, and the introduction path 7
7 and close the paper ejection path 76, or conversely, open the paper introduction path 77.
It changes depending on whether the paper ejection path 76 is opened or closed.

The copy paper 41 sent downward (FIG. 3) through the paper ejection switching unit 70 is fed into the ADU 80 (step ①).
).

The copy paper 41 conveyed to the reversing conveyance section 80 is transferred to the pulley 81.
The paper is turned over from the roller 82 on the lower surface of the paper and discharged toward the stacker 83 to the left.

The ejected copy paper 41 descends along the slope of the stacker 83, slides on the surface of the stopper 84, comes into contact with the abutment surface, and stops. Subsequent copy paper 41 that is subsequently sent in
The copy sheets 41 are also deposited one after another on the stacker 83 and the stopper 84, and the leading edges of the copy sheets 41 are aligned by coming into contact with the abutment surface.

In the second state, when a paper refeeding start signal is generated by the ADU control unit 114, the roller 85 is driven and rotated by the ADU drive unit 123, and the separation belt 86 is rotated in the direction of the arrow (FIG. 3). As a result, the plurality of copy sheets 41 stacked on the stacker 83 are sent out to the right in FIG. 3.

The copy paper 41 is then conveyed by the pressure contact port 3 between the paper feed roller 87 and the paper feed roller 87', and the passage of the leading edge of the copy paper 41 is detected by the ADU passage sensor 89 composed of a photosensor. Ru. The copy paper 41 is successively conveyed by paper feed rollers 87 and 87', and fed into the registration roller 62 (step 2). At this time, based on the detection result of the ADU passage sensor 89, the rotation of the roller 85 and the separation belt 86 is stopped.

Thereafter, the copy paper 41 undergoes back side copying on the photoreceptor 30 (step ■), is fixed in the fixing device 50, and then passes through the reversal paper discharge processing section 76 of the paper discharge switching section 70. It is discharged outside the sorter 90.

In this way, the back side copying of the first copy paper 41 is completed by paper refeeding, and then a paper refeeding start signal is manually input.
The next copy sheet 41 that is on standby on the stacker 83
paper refeeding will start. After that, the above-mentioned paper refeeding operation,
The back side copying operation is continuously performed for the set number of sheets N.

Here, in the present invention, the absence of the copy paper 41 on the stacker 83 is detected by the ADUO sheet detection sensor 88 (step [phase]), and the ADU passage sensor 89
When the passage of N copy sheets (re-feeding) is detected (step 2), the timer 120 starts counting in response to an instruction from the timing control section 111 (step 0).

In addition, when the ADUO sheet sensor detects that there are 0 sheets,
If the DU passage sensor 88 has not counted N sheets, a jam may occur, so jam processing (step 0) is performed.

Note that a predetermined count value is written in advance in this timer 120 by the timing control section 111 (step 2).

This count value satisfies the following two conditions.

[First condition] The copy paper sent out from the ADU 80 is placed on the registration roller 6.
2 (FIG. 2(C)), the next blank sheet from the paper feed unit 40 waits at the registration roller 62 (FIG. 2(D)).
)) The paper feeding timing is as follows.

That is, from the ADU passage sensor 89 to the registration roller 6
Paper passing time until 2nd pass is tI+ Delivery rollers 43a to 4
If the paper passing time from 3c to just before the registration roller 62 (varies depending on the position of the paper feed cassette) is t2, then the time when the copy paper passes the ADD passage sensor 89 (see Fig. 2) is t2.
1) Start the timer 120 with A) (Fig. 2 (1)
A' J, copy paper from ADU80 is on registration roller 6
2 and before being ejected from the final ejection port (between C and E in Fig. 2 (1)), the next blank sheet from the paper feed section 40 waits at the registration roller (Fig. 2 (1) ) D) The timing is such that the count is counted up at the paper feeding timing.

[Second condition] ADU80 passed through the registration roller under the first condition above
After the final copy sheet from 2000 has finished copying both sides and is discharged from the final discharge port (FIG. 2 (1) E), the first copy sheet on which the first side has been copied reaches the ADU 70. The timing is as shown in (Fig. 2 (1) F).

In the case of the above configuration, the paper feeding path length differs depending on the position of the selected paper feeding cassettes 42a to 42c, and therefore the paper feeding time also differs. Therefore, the timing control circuit 12 uses these data. See also 2 above
The timer 120 is set so that the conditions are satisfied.

In addition, the count value of the timer 120 is set in consideration of the difference in the final discharge position (for example, one sorter, two bins, no sorter) and the transfer speed.

Therefore, when the timer 120 counts up (step [phase]), the paper feed roller control unit 116 generates a paper feed start signal, and the paper feed roller drive unit 125 that receives this signal drives the paper feed roller 61 to rotate. do.

As a result, after the final re-feeding from the ADU 80 is completed (after passing the registration rollers 62), a blank sheet for copying the next document is conveyed to the registration rollers 62.

As a result, the first effect is that productivity during double-sided copying can be improved.

In addition, as a second effect, the setting time of the timer 120 is determined so that the copy paper from the ADU 80 passes through the registration rollers 62 and waits for the next blank sheet at the registration rollers 62, so the paper feed cassette 42a Irrespective of the difference in paper passing path length due to the difference in the position of 42c, it is possible to match the waiting timing of the copy paper in front of the registration roller. Therefore, even if the position of the paper feed cassette is different, productivity can be improved while maintaining a constant state.

As a third effect, the copy paper on which the first side has been copied does not reach the ADU 80 until the final copy paper on which both sides have been copied is discharged, so that paper jams can be easily handled. That is, if a paper jam occurs near the final ejection port 91 (which is most likely to occur), subsequent copy sheets are stopped in front of the ADU 80 and can be easily removed. In such a case, if the succeeding paper is stacked inside the ADU, the process of removing it becomes troublesome.

However, according to this embodiment, it is possible to easily deal with the occurrence of a jam.

Furthermore, the timer 120 does not need to satisfy the above conditions under all conditions, and may have a mode in which the next blank sheet is fed to the registration rollers after the last sheet is ejected from the final ejection position. The configuration may be such that one of the two can be selected.

FIG. 5 is a characteristic diagram comparing the time required for double-sided copying of N copies of six double-sided originals between the conventional method and the present embodiment. As is clear from this figure, according to this example,
By placing a blank sheet of paper on standby in front of the registration rollers in advance, copying time can be shortened and productivity can be improved.

(Effects of the Invention) As described above in detail, in the present invention, the copy sheet whose first side has been copied is reversed by the reversing transfer section, and the second side is copied onto the copy sheet sent out from the reversing transfer section. In an automatic double-sided copying device that performs this process, there is a timer that counts according to a set count value, and a timer that sets the count value in the timer and starts counting the timer at the timing when the last copy sheet is sent out in the reversing transfer section. It is equipped with a timing control section and a paper feed roller control means for driving a paper feed roller to send out blank paper when the timer counts up, and the count value set in the timer by the timing setting section is sent out from the reverse transfer section. After the last copy sheet passed through the registration rollers and before the final ejection, the blank sheet from the paper feed section of the main body is fed by the paper feed slot just before the registration rollers, and the duplex copying is completed. The value is such that the copy paper on which the first side has been copied reaches the ADU after the copy paper is discharged from the final discharge port.

As a result, a predetermined count value is set in the timer by the timing control means, and the timer starts counting at the timing when the last copy sheet is sent out in the reversing transfer section, and when the timer counts up, paper is fed. A paper feed roller for feeding blank paper is driven by the roller control means.

As a result, after the last copy sheet sent out from the reversing transfer section passes the registration rollers and before the final ejection, the copy paper from the main body paper feed section is fed by the paper feed rollers just before the registration rollers. Ru. Then, the copy paper fed in this manner reaches the reversal transfer section after the first side has been copied and the last copy paper on which double-sided copying has been completed is finally discharged.

Therefore, the time from the end of the second side copy to the start of the first copy of the next original is shortened, making it possible to improve productivity during double-sided copying, and also to prevent paper jam from occurring at the final ejection port. However, it is possible to realize an automatic double-sided copying apparatus that can cope with such problems.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of an automatic double-sided copying apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram for explaining the characteristic parts of this embodiment, and FIG. 3 is similar to FIG. FIG. 4 is a flowchart for explaining the operating state of the device of this embodiment; FIG. FIG. 2 is an explanatory diagram for explaining the productivity of the automatic double-sided copying apparatus according to the embodiment. 1... Original 2... Platen glass 1
0...RADF 20...Optical system 30...
Photoreceptor 40... Main body paper feeding section 41a to 41c.
Copy paper 42a to 42c Paper feed cassettes 43a to 43c Delivery rollers 44a to 44c Delivery belt 50 Fixing section 61 Paper supply roller 62
... Registration roller 70 ... Paper ejection switching section 80 ...
・ADU 88...ADUO sheet sensor 89
... ADU passage sensor 90 ... Stacker 100 ... Control section 110.
...CPU 111...Timing control section 112...RADF control section 113...Photoconductor control section 114...ADU control section 115...Registration roller control section 116...Paper feed roller control section 120 ...Timer 121...RADF drive section 122...Photoconductor drive section 123...ADU drive section 124...Registration roller drive section 125...Paper feed roller drive section

Claims (1)

[Claims] Automatic double-sided copying in which the copy paper on which the first side has been copied is reversed by a reversing transfer section (80), and the second side is copied onto the copy paper sent out from the reversing transfer section (80). The device includes a timer (120) that counts according to a set count value, a timer (120) that sets the count value in the timer (120), and a timer (120) that performs counting according to the set count value, and a timer (120) that sets the count value in the timer (120) and starts the timer (120) at the timing when the last copy sheet is sent out from the reverse transfer section (80). 120), and a paper feed roller control unit that drives the paper feed roller (61) to send out blank sheets (41a, 41b, 41c) when the timer (120) counts up. means (116, 125), and the count value set in the timer (120) by the timing setting section (111) is determined when the last copy sheet sent out from the reverse transfer section (80) passes through the registration roller (62). The main paper feed section (40)
The blank paper (41a, 41b, 41c) from the paper feed roller (
61), the copy paper is fed just before the registration roller (62), and the copy paper that has been copied on both sides is delivered to the final ejection port (9).
1) An automatic double-sided copying apparatus characterized in that the value is such that the copy paper whose first side has been copied reaches the reversal transfer section (80) after being ejected from the machine.