JPS60136759A - Both-surface copying machine - Google Patents

Abstract

PURPOSE:To shorten copying time by conveying an original to a rear stage side by utilizing an automatic original conveying device after detecting a set number of sheets of surface-copied transfer paper being stored in a transfer paper inverting intermediate tray. CONSTITUTION:This both-surface copying machine has a transfer paper inverting device 22. This transfer paper inverting device 22 consists of a transfer paper inverting device 23 which conveys only one sheet of transfer paper 7a to the rear stage side immediately after turning over the sheet and the transfer paper inverting intermediate tray 24 which is positioned below said device and stores plural sheets of transfer paper 7a and then inverts and feeds the sheets. Consequently, the automatic original conveying device is utilized to move the original to the rear stage side after detecting a set number of sheets of surface- copied transfer paper being stored in the transfer paper inverting intermediate tray, shortening the copying time.

Description

[Detailed description of the invention] Technical field The present invention relates to a single-sided copying machine.

PRIOR ART Conventionally, there are various types of double-sided copying machines, but generally speaking, as shown in Japanese Patent Publication No. 49-36264,
The transfer paper transport path is formed in a loop shape including a double-sided 1-lay. As a result, the probability that the transfer paper will jam is high.
In addition to frequent problems, the time required for double-sided copying is long.

In this regard, U.S. Patent No. 3,536,398 and
There is also a double-sided copying machine using two photosensitive drums, as shown in Japanese Patent No. 61559. However, even with this method, in order to match the image orientation between the front and back copies,
It is not sufficient as it requires complicated improvements to the optical system.

Purpose The present invention has been made in view of the above points, and provides a new double-sided copying machine proposed by the applicant, which is capable of simplifying the transport path of transfer paper, reducing jams, and shortening the copying time. To provide a double-sided copying machine capable of performing appropriate processing in a double-sided copy mode.

composition An embodiment of the present invention will be described with reference to the drawings.

First, two photoreceptor drums la are used as image recording bodies.

1b are juxtaposed in the front and rear rows. These photoreceptors 1:
An optical system 5 exposes and images the original on glasses 4a and 4b to chargers 2a and 2b, erasers 3a+3b and contactor 1 according to an electrophotographic process for rams la and lb.
a, 5b, developing devices 6a, 6b, paper feed sections 8a, 8b for transfer papers 7a, 7b, separation transfer chargers 9a, 9b, cleaning devices 1Oa, ]Ob, static eliminator [Wlla, I
lb, fixing device 128. +2b is provided. Here, automatic document feeders +'3a and +3b are provided on the contact glasses 4a and 4b. These automatic document conveyance devices [13a, 13b are mainly composed of "transfer belts 16a, +6.b" for conveying the documents 15a, 15b that have been placed on the document tables 1.4a, 14bl, and a recycling bus 17a. ,,17b are also provided.

In this way, the front-stage image forming means 18a and the rear-stage image forming means 18b are formed.

Such front/back image forming means 18a, 18bl'J
, the transfer paper conveyance path 20, and the document conveyance path 2]. First, the transfer paper conveyance path 20 includes a photoreceptor drum la,
1. The transfer paper 7a is conveyed from the front stage side to the rear stage side by connecting the space 7b, and is formed in a substantially straight line, and has a transfer paper and transfer sheet [22] in the middle. This transfer paper reversing device 22 includes a transfer paper reversing and conveying device 23 that can invert only one sheet of transfer paper 7a and immediately transport it to the subsequent stage side, and a transfer paper reversing and conveying device 23 that is located below it and can accommodate a plurality of sheets of transfer paper 7a, and then reverses it. It is composed of a transfer paper reversing intermediate 1 and a lay 24 that can feed paper. As is well known, the transfer sheet reversing conveyance device 23 is composed of three roller pairs 25 and a reversing path 26, and as shown in the figure, the upper two subordinate rollers of the three roller pairs 25 open the reversing path 26. For example, the transfer paper 7a enters the reversing path 26 and is reversed and conveyed, but if the first reversing path 26 is closed, the transfer paper 7a simply passes through without being reversed.

The transfer paper reversing intermediate 1-lay 24 is provided with a partition pressure plate 27 and a paper feed roller 28 . and.

A switching claw 29 is provided for selectively switching between the transfer paper reversing and conveying device 1I23 side and the transfer paper reversing intermediate tray 24 side. Furthermore, a second intermediate tray 30 that can accommodate the reversed transfer paper 7a is provided downstream of the transfer paper reversal conveyance device 23, and is provided in parallel with the transfer paper conveyance path 20 together with a paper feed roller 31, so that both A switching claw 32 for switching selection is provided. On the other hand, the document conveyance path 21 is also an automatic document conveyance device L 3 a.

+3b is connected to transport the original L5a from the front stage side to the rear stage side l\, and it is formed in a substantially straight line, and a manuscript transfer unit [35 is provided in the middle thereof.

The document reversing device 35, like the transfer paper reversing conveyance/feeding station 23, is composed of three rollers χ' 36 and a reversing path 37, and the first reversing path 37 also serves as manual document feed. Here, a switching claw 38 for selectively switching between the document transport path 21 side and the recycle bus 17a side is provided at the rear stage of the automatic document feeder 13a, and a paper discharge 1 provided for the automatic document feeder 13a is provided.
- A single-swing claw 40 is provided for selectively switching between the ray 39 side and the recycle path 17a side.

Next, a reversing discharge device 53 having a paper folding stopper 52 as well as a three-roller pair 50 and a reversing path 51 is provided at the rear stage of the constant young feed [1, 2b] on the photosensitive drum 11) side, and a switching claw is installed at the rear stage. Output tray 5 selected from 54
5 and a sorter 5G are provided. Further, at the rear stage of the automatic document feeder 1.3b, there are three roller pairs 57 and a reversing path 5.
8 and a paper ejection tray 60 via a reversing ejection device 59 having
is provided. Reference numeral 61 denotes a switching claw for selectively switching between the reversing 111i sending gear 59 side and the recycling bus 17b side.

Note that 70 is a manual paper feed section provided in parallel with the paper feed section 8a.

With such a configuration, the double-sided copying machine of this embodiment can handle various aspects. Although switches, control circuits, etc. are not particularly illustrated here, various modes can be set freely.

First, let us consider a repeat duplex copy mode in which a predetermined number of double-sided copies are made from a single double-sided original. At this time, the original 15a is set on the original table 14a-1-. However, when copying starts, this document 15a
is fed and transferred to the contact glass 4 by the conveyor belt 16d.
a and stops. Therefore, the optical system 5a exposes and scans the surface of the original 15a on the contact glass 4.1-1 to form a latent image on the rotating photoreceptor drum lsia.

This latent image is the current Tsukuda'! After being developed by the device 6a, the image is transferred to a transfer paper 7a fed at a predetermined timing from the paper feed section 8a by the action of the separation transfer charger 9a. Then, it passes through the fixing device 12a and the surface copying of the transfer jJt7al\ is completed. Such an operation is repeated on the photosensitive drum la side for each document +5a fed and set on the contactor 1 to the glass 4a, and a 1M copying operation is repeated for the number of copies of the document +1, thereby creating a front side copy. The transfer paper 7a on which the front side has been copied is sequentially discharged to the transfer paper reversing intermediate tray 24 and temporarily stored therein. When the front side copying for the number of repeat sheets is completed, the original 1.5a on the contact glass 4a is reversed by the original reversing device 35 and transferred onto the contact glass 4b. On the other hand, a paper discharge number detection means is provided in the transfer paper reversing intermediate tray 24 or in the conveyance path just before it, and when it is detected that the transfer paper 7d corresponding to the repeat number of sheets has been stored, the partition pressure plate 27 is activated to feed the paper. roller 28
side, and enters a standby state for paper feeding to the photosensitive drum lb side. As a result, the original KA l 5 a set on the contacts 1 to glass 4b-1 will be copied to the llj side on the photosensitive drum Ib side, and the transfer paper 7a whose front surface has been copied will be transferred to the intermediate 1 to 24 Then, the sheets are sequentially fed one by one in an inverted state by the paper feed roller 28, and double-sided copying is completed.

Next, consider a 1-1 duplex copy mode in which one double-sided copy is made from one double-sided original, which is also a double-sided original-two-sided copy mode. Basically, it is the same as in the repeat double-sided copy mode described above, but the switching claw 29 is switched and the transfer paper reversing conveyance device 23 is selected instead of the transfer paper reversing intermediate tray 24. At this time, the original 15a is placed on the original platen 1.
Set it on 4a. When copying is started, the document +5a is fed, conveyed onto the contact glass 4a by the conveyor belt 16a, and stopped. Therefore, the optical system 5a exposes and scans the surface of the document 15a on the contact glass 4a to form a latent image on the rotating photoreceptor drum la. After this latent image is developed by the developing device 6a, it is transferred to the transfer paper 7a fed at a predetermined timing from the paper feed section 8a side by the action of the separation transfer charger 9a.

Then, the image passes through the fixing device 12a and the surface copying onto the transfer paper 7a is completed. When the front side copy is completed in this way, the original 15a on the contact glass 4a is conveyed by the conveyor belt 16a to the original reversing device 35, and is turned over by the original reversing device 35 so that the back side is facing down. 13a side, and is set on the contactor 1-glass 4bJ2 by the conveyor belt 16b. At the same time, the next document 1 is placed on the side of the automatic document feeder], 3a.
'5a is set on contact 1-glass 4a.

On the other hand, the transfer paper 7a whose front surface has been copied is sent from the fixing device 12a to the transfer paper reversing conveyance device 23, where it is reversed so that the uncopied straight side faces upward, passes through the transfer paper conveyance path 20, and is transferred to the photoreceptor drum 1b. On the other hand, it is in a standby state.

Therefore, backside copying is performed on the photosensitive drum lb side (at this time, frontside copying of the next document is performed on the photosensitive drum la side). That is.

The back side of the original 15a set on the contact glass 4b is exposed and scanned by the optical system 5b to form a latent image on the photoreceptor drum lb, and according to the development, transfer and fixing process, a back side copy is made on the back side of the transfer paper 7a on which the front side copy has been made. will be formed. Then, the original 15a and the transfer paper 7a on which both sides have been copied are discharged to paper discharge trays 60, 55, etc. (they are reversed or the sorter 56 is selected as necessary).

Also, in the double-sided copy mode, consider the case where a double-sided copy is obtained from a single-sided original. In this case as well, there is a 1-1 duplex copy mode and a repeat duplex copy mode, but in the former case, the transfer paper reversal transport bag @23 is selected, and in the latter case, the transfer paper reversal intermediate tray 24 is selected. Ru. on the other hand,
Regarding the original side, first set all the originals on the original table lJa of the automatic document feeder 13a, and after the front side copy is completed on the photoreceptor drum la side for the odd numbered (front side) original +5a, this contact While the second odd-numbered original 15a is immediately ejected through the original transport path 21 and the contact glass 4b, the next even-numbered original (for the back side) 1'5a on the original platen 14a is passed through the contact glass 4a and the original. It is made to pass through the conveyance path 21 and conveyed and set on the contact glass 4b to be used for back side copying. That is, the document reversing device 35 becomes inactive.

In any case, in the double-sided copy mode, the front-stage image forming means 18a creates the front-side copy mode, and the rear-stage image forming means 18b creates the back-side copy to complete the double-sided copy. In this case, the transfer paper 7a
is conveyed from the photoreceptor drum 1a side to the photoreceptor drum 1 )) side by a substantially linear and short transfer paper conveyance path 20.
The probability of occurrence of the transfer paper jam 11 is lowered, and the copying speed is also improved. This also applies to the document side, and since the document transport path 21 connecting the automatic document transport stations 13a and 13b is substantially straight and short, document jams are reduced. Further, after the front side of the transfer paper 7a is copied, it is reversed by the transfer paper reversing device 23 and conveyed to the photoreceptor drum 1b side, which is equivalent to the case where the paper is fed toward the photoreceptor drum 1a, and the optical system 5a , 5b and the like can be made exactly the same for both the photosensitive drums 1a and 1b3iJ.

Therefore, the orientation of the image must be adjusted as usual.

There is no need to make complicated improvements to the optical system, and it can be simplified.

Furthermore, as a result, it is possible to adopt a method in which originals are simply passed from the front side to the rear side, and by using the automatic document feeders 13a and 13b, it is possible to automatically perform a large amount of double-sided copy processing in a short time. be.

Further, the transfer paper reversing device 22 is composed of a transfer paper reversing conveyance device 23 and a transfer paper reversing intermediate tray 24, which are arranged oppositely above and below the transfer paper conveying path 20, and both can be freely selected by a switching claw 29, and both sides can be Even if it’s a copy! -1 In the double-sided copy mode, the transfer paper reversing and conveying device 23 is selected, and the transfer paper 7a on which the front side has been copied is reversed and immediately sent to the subsequent stage, so that the time required for double-sided copying is shortened. On the other hand, in repeat duplex copy mode, transfer paper reversal intermediate 1
~ray 24 is selected and the transfer paper 7a on which one side has been copied is temporarily stored, making it easy to align it with the original 15a on the automatic document feeder I3a side. That is, even if the transfer paper 7a on which the front side has been copied is immediately sent to the photosensitive drum 1b side during repeat, the original for the back side is on the automatic document feeder 13a side and is not ready for copying, so the transfer paper inversion intermediate tray 2
4, the standby state becomes effective. Also, by checking the number of 78 transfer sheets actually discharged and stored in the transfer sheet reversal intermediate 1-lay 24, repeat sheet number checks, jam checks, etc. can be made more reliably. Furthermore, when copying the back side, the transfer paper 7a is transferred to this transfer paper reversal intermediate 1.
- Paper is continuously fed one sheet at a time from the lay 24 to the photosensitive drum lb side, and the latter image forming means 1': 218
b The paper feeding condition is the same as in the case of a standalone machine, and the copying time is not delayed by one hour. That is, in the l-4 double-sided copy mode, the transfer paper 7a can be processed individually by the transfer paper reversing conveyance device 23, and in the repeat double-sided copy mode, the transfer paper 7a can be processed in batches by the transfer paper reversing intermediate tray 24. Appropriate processing will be carried out depending on the situation.

By the way, as mentioned above, in the 1-] double-sided copy mode, the transfer paper reversing and conveying device 23 is used.
The transfer paper 7a may jam in the transfer paper reversing and conveying device 23. Generally, when a jam occurs in a copying machine, the machine cannot be restarted unless the machine is stopped and the jam is cleared. However, in this embodiment, when a transfer paper jam is detected in the transfer paper reversing conveyance device 23, even in the 1-1 double-sided copy mode, the switching claw 29 is switched by this jam detection signal, and the transfer paper reversing intermediate tray 24 is switched. is used to continue the 1-1 double-sided copying operation. At this time, the double-sided original that has been subjected to front-side copying and the corresponding back-side original are immediately processed to be ejected onto the 1 to Rayo 0 side of the paper eject. Looking at the copy continuation status,
The jammed paper in the transfer paper reversal conveyance device 23 remains as it is, and the next copy of the back side continues, and the transfer paper 7a is ejected from the transfer paper reversal intermediate tray 24, and is immediately fed to the photosensitive drum 1b side to copy the back side. Provided for copying. and,
After the copying operation is completed, double-sided copying is performed using the document corresponding to the jammed transfer paper, and after completion of the copying, the machine is stopped and the jammed paper in the transfer paper reversing and conveying device 23 is disposed of. . In this way, even if a jam occurs in the transfer paper reversing conveyance device w23, the copying operation continues without stopping the device and double-sided copies are obtained, so it is possible to deal with urgent cases and improve copying efficiency. .

In particular, since the transfer paper reversing conveyance device 23 is located not at the final paper ejection section but inside one machine, it is difficult for the operator to clear the jam and it may be necessary to have a service person handle it. It is extremely effective to be able to perform copy processing without performing jam removal in the middle.

In this embodiment, the transfer paper reversing conveyance device 23 is used when operating in the 1-1 duplex copy mode. However, the transfer paper reversing intermediate tray 24 may always be used.

Furthermore, a single-sided copy mode can also be selected, and various single-sided copy processes can be performed. First, although the double-sided copying machine of this embodiment can perform double-sided copying by linking the front and rear image forming means 18a and 18b, each of the front and rear image forming means 18a and 18b can be operated independently by a changeover switch (not shown). It can be driven by In other words, there are two independent copying machines, and each automatic document feeder 13a,
Set originals 15a and 15b on 13b, transfer paper 7a,
By feeding paper from each of the paper feed sections 8a and 8b, one-sided copying can be performed simultaneously using the photosensitive drums la and Ib, optical systems 5a and 5b, etc. in parallel. Therefore, when copying a large amount of copies, if the copying is done by dividing the copying process, the time will be halved, resulting in high-speed processing. In this case, the original 15a is ejected to the paper ejection tray 39, and the transfer paper 7a
is discharged to the transfer paper reversing intermediate tray 24.

Next, one-sided copying that takes advantage of the feature that the front and rear image forming means 18B and 18b are linked will be explained.

For example, you may want to make a single-sided copy of a double-sided original.
In this case, a double-sided original is set on the original table +4a, the front side of the original is single-sided copied onto the transfer paper 7a on the photosensitive drum la side in the same way as the front side copying, and this transfer paper 7a is ejected to the transfer paper reversing intermediate tray 24. Paper. After this operation is completed, the original 15a on the contact glass 4al is reversed through the original reversing device 35 and conveyed and set on the contact glass 4b.

Then, one-sided copying of the original 15a is performed on the transfer paper 7b on the side of the photosensitive drum Ib. By repeating the same operation, double-sided original-single-sided copy processing can be performed automatically.

Next, the coexistence of five-sided copying and single-sided copying will be explained. First, when normal one-sided copying is required, the first-stage image forming means 18a is not used, and only the second-stage image forming means 18b is used to perform the one-sided copying. As a result, the front-stage image forming means 18a is not in use, and if double-sided copying is required, the rear-stage image forming means 18h
In parallel with the single-sided copying performed by the image forming means 18a, front-side copying processing can be performed by the front-stage image forming means 18a. The transfer paper 7a on which the front side has been copied is temporarily stored in the transfer paper reversing intermediate tray 24. and subsequent image forming means]
, 8b, after the single-sided copying is completed, the rear-side copying may be performed by the subsequent image forming means 18b. At this time, the transfer paper 7a is transferred to the transfer paper reversing intermediate tray 2.
Since the paper is fed from 4 and the paper feeding state is the same as that of normal one-sided copying, and there is no need to wait for processing on the front-stage image forming means +8a side, it only takes a short time +ty.

Such processing is also effective for interrupt copying during double-sided copying. That is, at the time of interruption copying (single-sided copying), the subsequent image forming means 18b is used to perform the processing. At this time, the interrupted original is manually fed from the reversing path 37. Then, the front side copying process by the front image forming means 18a is continued, and the transfer paper 7a is stored in the transfer paper reversing intermediate tray 24. After the interrupt copying is canceled, back side copying of the transfer paper 7a in the transfer paper reversing intermediate tray 24 may be resumed by the subsequent image forming means L8b.

This is the same when a jam occurs on the side of the rear image forming means 18b, and the latter image forming means 18b is stopped, but the front side copying by the front image forming means 18a continues and the transfer paper 7a is rotated between 1-Store in Ray 24,
After the jam is cleared, it is sufficient to restart the back side copying by the subsequent image forming means 18b.

In this way, also in the single-sided copy mode, the transfer paper reversing intermediate 1-lay 24 can be used as a paper discharge tray for the front-stage forming means 18a, and various single-sided copy modes can be handled.

Effects As described above, the present invention has a basic configuration in which a plurality of image recording bodies are connected and connected by a transfer paper conveying path including a transfer paper reversing device, and the transfer paper reversing device is configured with a transfer paper reversing intermediate tray, and a set number of image recording bodies are connected. After detecting that the transfer paper on which the front side has been copied is stored in this transfer paper reversing intermediate tray,
By using an automatic document feeder to transport the original to the latter stage and re-feeding the transfer paper to perform backside copying, it is possible to perform batch processing, especially for repeat double-sided copying, and even single-sided copying. It can also be effectively used for copying purposes.

[Brief explanation of drawings]

The drawing is a schematic side view showing an embodiment of the present invention. 18~lb...Photosensitive drum (image recording body), 58~
5b...Optical system, 7a...Transfer paper, 20...Transfer paper conveyance path, 13a-13b...Automatic document conveyance device, 2
1... Original transport path, 24... Transfer paper reversing intermediate tray, 35... Original reversing device

Claims (1)

[Claims] A plurality of image recording bodies are provided, each of these image recording bodies is provided with an optical system and an automatic document feeder, and a transfer paper reversing intermediate tray is provided which temporarily stores a plurality of transfer papers in an inverted state and re-feeds and transports them. The image recording media are connected by a transfer paper conveyance path, and the automatic document conveyance device is connected by a document conveyance path having a selectively operated document reversing device. After detecting that the set number of sheets have been stored in the transfer paper reversing intermediate tray, the front and rear automatic document feeders are operated to set the back side original on the rear image recording body, and the transfer paper reversing intermediate tray This double-sided copying machine is characterized in that the transfer sheets stored in the machine are sequentially re-fed and conveyed to a later-stage image-recording body, and the rear-side copy is performed by the latter-stage image-recording body to complete double-sided copies for a set number of sheets.