JPH11143299A - Dolible-sided copying machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-sided machine copying capable of shortening the time required for double-sided copying operation or the like and eliminating trouble for separating the odd and even numbered pages of documents with manual work. SOLUTION: An automatic document feeder 2 is provided and constituted so that the images of plural documents are copied on both surfaces of recording papers respectively. In such a case, the double-sided copying machine is provided with a document retreating part 3 for retreating the second document, while the first recording paper after the first document is recorded on one surface is turned inside out and returned to a paper feeding side, a document carrying means for carrying the document in the document retreating part 3 to a reading opposition and a copying control means 12 for retreating the second document into the document retreating part 3, after copying for the first document is completed and recording the third document on one surface of the second recording paper, the second document arriving at the reading position by the document carrying means on the other surface of the first recording paper after being turned inside out and returned and continuously, the fourth document on the other surface of the second recording paper after being turned inside out and returned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
Facsimile machine, or improvement of image forming apparatus such as these multi-function machine, more specifically, when performing double-sided copying,
The present invention relates to a double-sided copying machine or the like which improves the productivity by speeding up the copying operation by variously improving the recording paper conveyance sequence and the like.

[0002]

2. Description of the Related Art Conventionally, when performing duplex copying in a copying machine equipped with an automatic document feeder, one-sided copying and then copying on the other side are performed, as shown in FIG. The recording paper (copy paper) on one side of which has been completed in the fixing unit 7 and the fixing unit 8 is advanced to the reversing stack unit 9 via the path cd, and after being turned upside down in the reversing stack unit 9, the recording paper is passed via the path de. To the paper feed side. In other words, as shown in the operation flow of FIG. 14, when copying a single-sided original on both sides of a recording sheet, first, the first sheet (the lowermost side of the original stacked on the original feed tray 1 with the image side facing upward) (That is, the last page) is copied on the back side of the first recording sheet, for example (S51), the first recording sheet is reversed and returned (S52), and the image of the second document is returned. The developing unit 7 and the fixing unit 8 copy the front side of the first recording sheet (S5).
3). Subsequently, the image of the third document is copied on the back side of the second recording paper (S54), the second recording paper is reversed and returned (S55), and the image of the fourth document is returned. A copy is made on the front side of the second recording sheet (S56).

When copying a two-sided original on both sides of a recording sheet, as shown in FIG. 15, first, an image on the back side of the first double-sided original is copied on the back side of the first recording sheet ( S61),
The first document is reversed by the discharge / reversal roller 4 and returned.
The first recording sheet is inverted to e using the reversing stack unit 9 and returned (S62), and the front side image of the first document is copied onto the front side of the first recording sheet (S63). Subsequently, the back side image of the second original is copied to the back side of the newly fed second recording paper (S64), and the second original and the second recording paper are reversed and returned. (S65) The front side image of the second document is copied onto the front side of the second recording paper (S66). Therefore, such a two-sided copying machine has a problem that extra time is required as compared with the one-sided copying for the front / back inversion and the returning operation. In order to solve such a problem, in a copying machine disclosed in Japanese Patent Application Laid-Open No. 1-202767, in double-sided copying in which recording is performed on both sides of a recording sheet using a single-sided original, first,
The even pages are continuously copied only on one side of a plurality of recording sheets, the recording sheets are stored in an intermediate tray, and then the odd pages are continuously copied on the opposite side of the recording sheets fed from the intermediate tray. Like that.

[0004]

However, in the prior art disclosed in Japanese Patent Application Laid-Open No. 1-202767, there is a trouble that a manuscript must be manually divided into odd pages and even pages in advance. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems of the related art, reduce the time required for duplex copying and the like, and eliminate the trouble of manually separating odd pages and even pages of a document. Another object of the present invention is to provide a double-sided copying machine.

[0005]

According to a first aspect of the present invention, there is provided a double-sided copying machine having an automatic document feeder for copying a plurality of documents on both sides of a recording sheet. A document evacuation section for retreating the second document while the first recording paper on which the first document is recorded on one side is turned over and returned to the paper supply side; A document conveying means for conveying a document in a document retreat section to a reading position, and after the copying of the first document is completed, the second document is retreated to the document retraction section to record the third document. The second sheet of paper conveyed to the reading position by the above-mentioned document conveying means is recorded on the other side of the first sheet of recording paper which has been turned over and returned to the first sheet of recording paper. To copy the fourth document on the other side of the second recording paper returned And control means. According to a second aspect of the present invention, in a two-sided copying machine provided with an automatic document feeder for copying a plurality of double-sided originals on both sides of a recording sheet, the original having been read on only one side is retracted and turned over. Document reversing and reversing unit for re-feeding
After copying one side of the first original onto one side of the first recording paper, the original is retracted to the original retracting / reversing section, and one side of the second original is placed on the second original. The first document, which has been copied on one side of the recording paper and reversed upside down while the second document is being retracted to the document retracting / reversing section, is re-fed from the document retracting / reversing section to the reading position. It was copied on the other side of the first sheet of recording paper that returned and turned over,
Copy control means for re-feeding the second original from the original retracting and reversing section to the reading position, and copying the second original on the other side of the second recording sheet which has been reversed and returned. According to the third aspect of the present invention, in the above, the document retracting unit or the document retracting and reversing unit is configured so that a plurality of documents can be retracted, and the documents are read from the document retracting unit or the document retracting and reversing unit in the order of retreat. The copy control means is configured to convey the document to the position. According to the fourth aspect of the present invention, the document reversing and reversing unit is provided with a retreat paper path having a total length of a plurality of documents to be retreated. According to a fifth aspect of the present invention, in the third aspect of the invention, the document reversing and reversing section holds a plurality of documents to be retracted in an overlapping manner, and separates and retrieves the documents one by one in the order in which they are retracted. The structure provided with the separating means was adopted. According to a sixth aspect of the present invention, there is provided a double-sided copying machine provided with an automatic document feeder for copying a plurality of double-sided documents on both sides of a recording sheet, a document reading means for simultaneously reading images from both sides of the document, Means for storing image information read by the means, and a recording sheet which is read from both sides of the original and fed after completing recording of one side of the original is a blank recording sheet on both sides. If there is, read from both sides of the succeeding document and record on one side of the document, and when the recording paper recorded on only one side is turned over and returned to the recording position, the corresponding other And copy control means for reading out the image information of the surface from the image storage means and recording the image information on the other side of the recording paper. According to a seventh aspect of the present invention, in a double-sided recording apparatus capable of recording on both sides of recording paper in accordance with print data from a host device, a data storage means for storing print data sent from the host device. If the recording paper fed after recording on one side or both sides is blank on both sides, the print data of the succeeding page is read from the data storage means and the recording for the print data is performed. When the recording paper recorded on only one side is turned over and returned to the recording position, the corresponding print data on the other side is read out from the data storage means and recorded on the other side of the recording paper. Print control means. In the invention described in claim 8, the print data of each page is configured to be bitmap-developed in a preset recording order. According to a ninth aspect of the present invention, in a print system including a host device and a double-sided recording device capable of recording on both sides of a recording sheet in accordance with print data from the host device, a print transmitted from the host device is provided. A data storage unit for storing data; and, if the recording paper fed after completion of recording on one side or both sides is a blank recording sheet on both sides, read out print data of a subsequent page from the data storage unit. When the recording paper recorded on only one side is turned over and returned to the recording position, the corresponding print data on the other side is read out from the data storage means. A print control means for recording on the other side of the recording paper is provided in the double-sided recording apparatus, and the printing is performed in the preset recording order. The chromatography data was provided in the host device transfer means for transferring the double-sided printing apparatus.

[0006]

According to the first aspect of the present invention, the first recording sheet on which the first document is recorded on one side is turned over and returns to the sheet feeding side. 3 in the coming period
The second document is recorded on the second sheet of paper,
Turn 2 on the other side of the first sheet of recording paper
The document of the fourth document is recorded, and subsequently, the document of the fourth document is recorded on the other surface of the second recording sheet which has been reversed and returned. According to the second aspect of the present invention, one side of the first original is copied onto one side of the first recording sheet, and then one side of the second original is placed on the second recording sheet. It is copied on one side, and then the other side of the first document that has been turned over and returned is copied on the other side of the first recording sheet that has been turned over and returned. The other side of the second document which has been turned over and returned is copied onto the other side of the second recording sheet which has been turned over and returned. According to the third aspect of the present invention, while the recording paper recorded on only one side returns, a plurality of pages of the subsequent document are copied on every other page on one side of the subsequent recording paper, and one side is copied. When the recording paper recorded only on the recording paper returns, recording on the other side of the recording paper is performed. According to the fourth aspect of the present invention, the plurality of retracted originals are held in the evacuation paper path side by side in the original traveling direction. According to the fifth aspect of the invention, the plurality of retracted originals are held in an overlapping state, and are separated and taken out one by one in the order in which the originals are retracted. According to the sixth aspect of the present invention, if the recording paper fed after the completion of both-side reading of the original and recording of one side of the original is a blank recording sheet on both sides, both sides of the subsequent original are scanned and the original is read. When recording on one side is performed, and the recording paper recorded on only one side is turned over and returned to the recording position, the corresponding image information on the other side is read out from the image storage means. It is recorded on the other side of the recording paper. In the invention according to claim 7,
If the recording paper fed after recording on one side or both sides is a blank recording sheet on both sides, the print data of the subsequent page is read from the data storage means and recorded, and recorded on only one side. When the recording paper is turned upside down and returned to the recording position, the corresponding print data on the other side is read from the data storage means and recorded on the other side of the recording paper. According to an eighth aspect of the present invention, in the seventh aspect of the invention, the print data of each page is bitmap-developed in a preset recording order. According to a ninth aspect of the present invention, in the seventh aspect of the invention, the print data is transferred from the host device to the double-sided recording device page by page in a preset recording order.

[0007]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory diagram of a two-sided copying machine showing a first embodiment of the present invention. As shown,
The two-sided copying machine according to this embodiment includes a document feed tray 1 on which a plurality of documents are stacked, and separates the documents one by one from the document feed tray 1 and transports the documents to a reading position, or moves the documents to the reading position. An automatic document feeder for discharging a document to the document discharge port 5 (= document conveying means, hereinafter referred to as AD
A document evacuation unit 3 that belongs to the ADF device 2 and temporarily retracts the document fed from the document feed tray 1 and belongs to the ADF device 2 and discharges the document to the document discharge port 5 A paper discharge / reversing roller 4 for reversing the sheet and reversing it to a reading position, a paper feeding cassette 6 on which a plurality of recording papers to be recorded are stacked, and forming (recording) an image read from a document on the recording paper. A developing unit (or image forming unit) 7, a fixing unit 8 for fixing an image formed on the recording paper, a reversing stack unit 9 for reversing the recording paper on which only one side has been recorded, and an ejection after copying is completed A paper ejection tray 10 for storing the recorded recording paper, a scanner unit 11 for reading an image from a document, and the like are provided. The developing unit 7
And the fixing unit 8 constitute an image forming unit. Here, the image forming unit of the electrophotographic image forming apparatus is illustrated, but the present invention is applicable to various printers, printing apparatuses, and the like. A printing unit and a recording unit may be provided.

FIG. 2 shows an operation flow chart of the first embodiment, and FIG. 3 shows a block diagram of a main part of a control system. Hereinafter, the operation of this embodiment will be described with reference to FIGS. First, the first sheet (the lowest page of the stacked originals, that is, the last page) of the single-sided original bundle set with the original surface facing upward on the original feed tray 1 is the original for controlling the ADF device. The document is sent out from the document feed tray 1 under the control of the transport control unit (document transport control means) 13 (FIG. 3).
The document is conveyed to a reading position in the DF device 2 (directly above the scanner unit 11), and reading is started under the control of a copy control unit (copy control means) 12 that controls the operation of each unit of the double-sided copying machine body. Also, under the control of the copy control unit 12, the first recording sheet, both sides of which are blank, is sent out from the paper supply cassette 6 and reaches the developing unit 7 through the passage a.
An image read from the first document is formed on the back side of the first recording sheet by the developing unit 7 (S1). continue,
The first original is ejected by an ejection / reversing roller 4 into an original exit 5.
The first recording paper recorded only on the back side is conveyed to the reversing stack unit 9 via the passage b, the fixing unit 8 and the passage cd. Then, by moving to the developing section 7 through the passage de, the front and back are reversed (S2). The first sheet of recording paper waits in the passage e. While the first sheet of recording paper is conveyed as described above, the second document is sent out from the document feed tray 1 and stopped in a state where it is retracted into the document retracting section 3. In other words, the document transport control unit 13 rotates the two transport rollers 3a and 3b in the document retreat unit 3 counterclockwise (in the case of FIG. 1) to draw in the document, and passes through the determination path indicated by the arrow to the above-mentioned condition. When the first half of the document is located in the passage v in the document retracting section 3, the transport rollers 3a and 3b are stopped to stop the document. The switching of the document conveying direction may be realized by, for example, rotating the branch claw 3A between a solid line position and a dotted line position.

Further, the document transport control unit 13 causes the third document to be sent out from the document feed tray 1, and the copy control unit 12
The second sheet of recording paper is newly transported from the paper feed cassette 6 to the developing unit 7, and an image read from the third document is recorded on the back side of the second sheet of recording paper (S2). Then, the third document is discharged to the document discharge port 5 by the discharge / reversing roller 4, and the second recording paper recorded only on the back side passes through the passage b,
The sheet is conveyed to the reversing stacking section 9 via the fixing section 8 and the path cd, and proceeds to the developing section 7 via the path de to be turned upside down (S3). Subsequently, the document transport control unit 13 rotates the rollers 3a and 3b counterclockwise for paper feeding, thereby transporting the second document retracted in the document retracting unit 3 to the reading position. When the first sheet of recording paper returns to a predetermined position (for example, before the recording position, or before the confluence position f of the passage e and the passage a, or at an appropriate position on the passage d or the passage e) (when the first recording paper arrives) ), Reading is started from the second document under the control of the copy control unit 12. When the first recording sheet reaches the developing section 7, an image read from the second document is formed on the surface of the first recording sheet by the developing section 7 (S3).

In this way, when the first recording sheet, both of which have been copied on both sides, is being conveyed to the discharge tray 10 via the fixing unit 8, the document conveyance control unit 13 conveys the fourth document to the reading position. When the second recording sheet returns to the predetermined position on the paths d and e (when it reaches the position), reading from the fourth document is started under the control of the copy control unit 12. When the second recording sheet reaches the developing section 7, an image read from the fourth document is formed on the surface of the second recording sheet by the developing section 7 (S4). Hereinafter, the fifth to eighth originals are copied in the same manner as the first to fourth originals. Thus, according to this embodiment, while the recording paper on which only one side has been recorded is turned upside down and returned to the position on the near side of the developing unit (recording position), copying to the next recording paper takes precedence. As a result, the time required for double-sided copying can be shortened. In order to realize this, it is not necessary to perform a complicated operation of separating the odd-numbered pages and the even-numbered pages of the document in advance, so that no extra work is required unlike the related art. As shown in FIG. 1, the two-sided copying machine of this embodiment includes the paper discharge / reversing roller 4, so that it is possible to read from a two-sided original. Becomes longer as before. In addition,
If the passage in the document retracting section 3 is configured to be long so that a plurality of documents can be retracted, or if a plurality of documents can be stacked and fed one by one, , The fourth and fifth embodiments can be obtained.

FIG. 4 is an explanatory view of a double-sided copying machine showing a second embodiment of the present invention. As shown in the figure, the duplex copying machine of this embodiment includes a document retracting reverse unit 14 instead of the document retracting unit 3 shown in the first embodiment (see FIG. 1). A paper feed roller (not shown) is disposed below the path s located to the left of the reversing roller 14B, and operates to feed the original that has entered the path s and held and held at the reading position. Hereinafter, the operation of this embodiment will be described with reference to the explanatory diagram shown in FIG. 4 and the operation flowchart shown in FIG. First, the first double-sided original (the lowest one of the stacked originals) of the double-sided original bundle set with the front side facing upward on the original feed tray 1 is moved to the original transport control unit.
13 is sent out from the document feed tray 1 under the control of
The sheet passes through the path x in the F device 2 and advances to the position of the paper discharge / reversal roller 4, is turned upside down by the roller 4 and returned to the reading position, and the reading of the back side of the first sheet is started under the control of the copy control unit 12. Is done. Also, under the control of the copy control unit 12, the first recording sheet, both sides of which are blank, is sent out from the paper supply cassette 6 and reaches the developing unit 7 through the passage a.
An image read from the back side of the first document is formed on the back side of the first recording sheet by the developing unit 7 (S11).

Subsequently, the first document is placed in the document retracting / reversing section 14.
, U → s →
And will be kept in this. The first recording paper recorded only on the back side is conveyed to the reversing stack unit 9 via the passage b, the fixing unit 8 and the passage cd. And the passage de
(S12). While the first document and the first recording paper are being conveyed as described above, the second document is newly sent out from the document feed tray 1 and passes through the path x in the ADF device 2. As described above, the sheet advances to the position of the paper discharge / reversing roller 4, is turned upside down by the roller 4, and returns to the reading position. Under the control of the copy control unit 12, reading of the back side of the second sheet is started. Also, under the control of the copy control unit 12, the second recording sheet, both sides of which are blank, is sent out from the paper supply cassette 6, and reaches the developing unit 7 through the passage a, and is read from the back side of the second original. The developed image is formed on the back surface of the second recording sheet by the developing unit 7 (S12).

Subsequently, the document transport control unit 13 retracts the second document to the document retracting / reversing unit 14
The first document, which has been retracted and turned inside out, is transported to the reading position by driving a paper feed roller (not shown).
When the first recording sheet recorded only on the back surface returns to the predetermined position, reading from the front surface of the first document is started under the control of the copy control unit 12. When the first recording sheet reaches the developing unit 7, an image read from the surface of the first document is formed on the surface of the recording sheet by the developing unit 7 (S13). In this way, when the first document whose copying has been completed on both sides is discharged to the document discharge port 5 and the first recording paper is conveyed to the discharge tray 10 via the fixing unit 8, the document conveyance control unit 13 Returns the second document, which has been retracted and turned upside down in the document retracting / reversing unit 14, to the reading position, and when the second recording paper returns to the predetermined position, two copies are controlled by the copy control unit 12. Reading is started from the front side of the original. When the second recording paper reaches the developing unit 7, 2
An image read from the surface of the first document is formed on the surface of the recording paper by the developing unit 7 (S14). Hereinafter, the third and fourth originals are copied in the same manner as the first and second originals. In this manner, according to this embodiment, while the recording paper and the original on which only one side has been copied are turned over and returned, one side of the next original is copied onto one side of the next recording sheet. Is performed in advance, the time required for duplex copying from a duplex document can be shortened.

FIG. 6 is an explanatory view of a double-sided copying machine showing a third embodiment of the present invention. As shown in the figure, the two-sided copying machine of this embodiment is arranged in parallel instead of the original retracting section 3 of the first embodiment or the original retracting section 14 shown in the second embodiment. The plurality of holding passages s ₁ , s ₂ , s ₃ ,
.. Are provided with a document retracting / reversing section 14a in which each document can be retracted or retracted / reversed.
Thus, in the two-sided copying machine according to the present embodiment, the original in which the recording paper recorded on only one side in the first embodiment is skipped by one (for example, after copying the back of the first original,
If the front of the first document is skipped and the back of the second document is copied), and the document does not return to the developing unit 7 even after the copying is completed, a plurality of documents are evacuated to the next document. Can be copied in advance. In addition, each holding passage s
_1, s _2, the paper feed roller at the bottom of s _3, not each shown is positioned to refeeding the document having entered into the respective passages in the reading position by the feed roller. More specifically, when re-feeding a document that has entered each of the holding paths s ₁ , s ₂ , and s ₃ through the paths t → u → s sequentially and then re-feeded to the reading position, the holding path s ₁ side The paper feed rollers rotate sequentially in a counterclockwise direction to feed each original.

When the original that has passed the reading position is retracted by the original retracting / reversing section 14a, the claw 14
By the action of A, each document is guided from the left entrance of each of the holding paths s ₁ , s ₂ , and s ₃ and is retracted into each path. afterwards,
To feed the original in each passage to the reading position, each feed roller may be driven counterclockwise. Roller 1
4B, the holding paths s ₁ , s ₂ , s ₃ ,...
When guiding each original, the guide plate indicated by reference numeral 14C may be rotated so as to be surely guided into each holding passage. Further, in order to sort the document that has passed the reading position from the left side of each path to each holding path, a guide plate 14D may be provided on the left side in the same manner. The guide plate 14D also serves as a guide when a document in each holding path is fed to a reading position.

In the double-sided copying machine having the configuration of this embodiment,
Even in the case of a two-sided original as in the second embodiment, a plurality of originals can be retracted and reversed. In the second embodiment, the back side is copied twice consecutively, and then the front side is copied twice consecutively. However, in the double-sided copying machine according to this embodiment, the continuous copying is performed twice (two sheets). If the back side of the original does not return to the paper feeding side even after the back side of the original has been copied, the back side of the original is copied three times (three sheets) continuously, and only the back side is copied. it a plurality of documents is retreated to the original retreat reversing section 14a in a counter clockwise (passage t → u → s), followed by the paper feed roller (not shown) provided on the retaining passage s _1, s ₂ ··· each , The front side is sequentially copied on each recording sheet three times or more. Thus, in the duplex copying machine of the present embodiment, it is possible to further reduce the time (speed) of duplex copying. Incidentally, the configuration of the original evacuation reversing unit 14a, and held guided in each retaining passage document from the left side of the retaining passage s _1, s _2, s _3, the retaining passage s ₁ during reading, s _2, s ₃ When the single-sided document shown in the first embodiment is copied onto both sides of the recording paper, a plurality of documents are retracted as described above by constructing the sheet feeding unit from the left side to the reading position. It becomes possible.

FIG. 7 is an explanatory view of a double-sided copying machine showing a fourth embodiment of the present invention. As shown in the figure, the two-sided copying machine according to the present embodiment is configured such that the document reversing and reversing section 14a shown in the third embodiment is replaced with a retreat paper having a total length of a plurality of documents to be retreated. This is realized by the path 14b. In other words, the originals retracted in the loop-shaped evacuation paper path 14b composed of the paths (paths) t and u are arranged in series in the running direction. This paper pass 14b
For example, a plurality of rollers 14b 'and an endless belt 14b "
, So that the belt 14b ″ can run in the direction of the arrow.

Further, in the double-sided copying machine according to the fifth embodiment of the present invention shown in FIG. 8, as shown, the original retracting and reversing section 14a shown in the third embodiment is replaced with a retracting unit. A plurality of originals to be stacked are held one on top of the other, and a lower paper feed roller of a passage s (not shown), which is separated and taken out one by one in the retracted order, and an upper separation roller 14c are provided. That is, by rotating the document stacked on the s portion (tray portion) in the figure counterclockwise (in the case of FIG. 8), a sheet feeding roller for feeding the sheet leftward in the drawing, and a separation roller for applying the sheet feeding pressure By 14C, the originals separated one by one from the lowermost portion of the plurality of originals held in the s section and returned to the left.
The separation roller 14C is configured to be able to move forward and backward from the position shown in the drawing so that the original on the s portion can be pressed.

Next, FIG. 9 is a block diagram of a main part of a control system showing a sixth embodiment of the present invention. As shown in the figure, the duplex copying machine of this embodiment has a scanner unit.
Two AD converters 15a, which digitize analog signals output from the two contact sensors 17a, 17b and the like in 11a.
15b and an image memory 16 for storing digitized image information, and two contact sensors 17a and 17b,
Images are read simultaneously from both sides of a two-sided document, and the read image information is stored in the image memory 16 via the copy control unit 12. Hereinafter, according to the operation flow diagram shown in FIG.
The operation of this embodiment will be described. In this embodiment, the image forming apparatus in which the evacuation unit 3 is removed from the ADF in FIG. 1 or the ADF in each of the embodiments in FIGS. Is assumed to be an image forming apparatus from which each has been removed. First, the value of n (count value of the number of sheets) in a predetermined area in the memory in the copy control unit 12 is set to 0.
(S21). Then, the first double-sided document is conveyed to the reading position, an image is read from both sides as described above, and the read image information is stored in the image memory 16 (S22). The document from which the image has been read is immediately discharged from the document discharge port 5. In this embodiment, there is no need for a means for retracting the document or turning it upside down.

Subsequently, an image is recorded on the back side of the first recording sheet according to the image information on the back side of the first sheet (S23), and the recording sheet is transported to the reversing stack section 9 (S24). Then, is the recording sheet on which only the back surface conveyed in advance has been returned (reached) to a position in front of the developing unit (for example, a position in front of the branching unit f or an appropriate position on the further side). It is determined based on the output of a paper passing sensor (not shown) or the like (S25). Immediately after the first back surface is recorded, no recording paper has been conveyed in advance, so that the recording paper does not return (S
No at 25). Therefore, if there is a next document that has not been read (No in S26), the second document is repeated from step S22. Then, in step S25, it is determined whether or not the recording paper has returned again. If the result of the second determination (S25) is also No, step S26 and subsequent steps are repeated. However, if it is determined that the recording paper is returned (it has reached the position before the developing unit) (S25 Yes),
The copy control unit 12 increases the value of n stored in a predetermined area of the memory by 1 (S27), reads out image information on the front side of the n-th document from the image memory 16, and returns the record returned according to the image information. An image is formed on the surface of the paper (S28).
That is, when the first recording sheet returns, an image on the surface of the first document is formed on the surface of the recording sheet. In this way, the recording sheet on which both-side copying has been completed is discharged to the discharge tray 10. When the recording on the returned recording paper is completed, the copy control unit 12 completes reading all the originals, the value of n becomes equal to the number of originals, and determines whether or not the recording is completed (S29). ). If the processing has not been completed (No in S29), the process is repeated from step S25. In addition,
If it is determined in step S26 that the reading has been completed (Yes in S26), the process proceeds to step S29. If it is determined in step S29 that the recording is completed (Yes in S29), the operation flow is terminated. Thus, according to this embodiment, the same effect as that of the third embodiment can be realized in a digital copying machine.

FIG. 11 is a block diagram of a main part of a double-sided recording apparatus showing a seventh embodiment of the present invention. As shown,
The double-sided recording apparatus of this embodiment includes a host interface unit 21 for receiving print data from a host device such as a personal computer, a print control unit 22 (print control unit), a RAM 23 (data storage unit), and the like. Double-sided recording can be performed by the same operation as in the embodiment. In the sixth embodiment, image information is read from a document and stored in an image memory prior to recording. In contrast, in this embodiment, a double-sided recording device prints from a host device before recording. The data is acquired, the print control unit 22 develops a bitmap of the print data, and stores the developed image information of each page in the RAM 23. Then, if the recording paper fed after the recording of one side or both sides is a blank recording sheet on both sides, the print control unit 22 reads the bit-mapped image information of the subsequent page from the RAM 23 and When the recording paper recorded on only one side is turned over and returned to the recording position (developing unit), the corresponding bit-mapped image information of the other side is read out from the RAM 23 and read. Record on the other side of the recording paper.

Further, a transfer means for transferring the print data to the double-sided recording apparatus in a preset recording order is provided in the host device. In the above description, the print data passed from the host device may be bitmap-developed immediately for all pages, or may be bitmap-developed in the order in which the print data is passed to the developing unit 7a. In the latter method, R
The storage capacity of AM23 can be reduced. This latter method is possible when the recording apparatus is designed, when the recording paper to be recorded next is either double-sided blank recording paper supplied from the paper supply cassette 6 or reversed upside down. This is because it is clear that the recording paper has been used. Thus, according to the seventh embodiment, the same effect as that of the sixth embodiment can be realized even when print data passed from the host device is recorded on both sides of the recording paper.

In the seventh embodiment, when the print data is transferred from the host device to the double-sided recording device, the transfer unit 31 provided in the host device does not transfer all the pages at once, but transfers the print data in advance. The pages may be passed one by one in the known recording order. That is, a transfer unit for transferring the print data to the double-sided recording apparatus in a preset recording order may be provided in the host device. As shown in the explanatory diagram of FIG. 12, the host device H develops the print data into a page buffer 32 (indicated by P.B.B. May be passed to the double-sided recording device in the following order.

In each of the above embodiments, the developing units 7, 7
“a” means an image forming unit (including a photoreceptor, a charging unit, an exposing unit, a developing device, a transfer device, and the like) in an electrophotographic copying machine, and printing in other printing devices and recording devices. Unit, recording unit, and printing unit. That is, a printing unit, a printing unit, a recording unit, and the like may be provided instead of the developing unit and the fixing unit. Therefore, for example, the present invention is not limited to electrophotographic copying machines, but also ink jet printers, wire dot printers,
The present invention can also be applied to various printing apparatuses, conventionally known printing apparatuses using ink, and the like.

[0025]

As described above, according to the first aspect of the present invention, the first recording sheet on which the image of the first document is recorded on one side is turned upside down to the sheet feeding side. In the returning period, the recording of the third original is performed on the second recording paper, and then the second original is printed on the other surface of the first recording paper which has been turned upside down and returned. The second document is recorded, and then the fourth document is recorded on the other side of the second recording sheet that has been reversed and returned, so that the time required for duplex copying can be reduced. The invention of claim 1 can be applied not only to a single-sided document but also to a case where an image is formed by reading from one side of a double-sided document. According to the second aspect of the present invention, one side of the first double-sided original is copied onto one side of the first recording sheet, and then one side of the second double-sided original is placed on the second side. Is copied on one side of the recording paper, and then the other side of the first double-sided document that has been reversed and turned back is turned on the other side of the first recording sheet that has returned and turned over. The two-sided original is copied, and the other side of the second double-sided document that has been turned over and returned is copied onto the other side of the second recording sheet that has been turned over and returned. The time required for double-sided copying can be reduced. According to the third aspect of the present invention, while the recording paper recorded on only one side is reversed and returned (reached) to the recording position or the re-feeding position,
A plurality of pages of a subsequent document are copied every other page on one side of the subsequent recording paper, and when the recording paper recorded on only one side returns, the recording on the other side of the recording paper is performed. As a result, the time required for duplex copying can be further reduced. According to the fourth aspect of the invention,
In the described invention, a plurality of originals can be retracted and turned upside down by arranging a plurality of retracted originals in series in the original traveling direction and holding them in an evacuation paper path. The effect is the same as that of the third aspect. According to a fifth aspect of the present invention, in the third aspect of the present invention, the plurality of evacuated documents are held in an overlapped state and separated one by one in the evacuated order to take out the plurality of documents. Can be evacuated and turned upside down. The effect is the same as that of the third aspect.

Further, in the invention according to claim 6, if the recording paper fed after completion of both-side reading of the original and recording of one side of the original is blank, both sides of the succeeding original are blank. When reading and recording for one side of the original are performed, and the recording paper recorded on only one side is turned upside down and returned to the recording position, the corresponding image information on the other side is stored in an image. Since the information is read out from the means and recorded on the other surface of the recording paper, the same effect as that of the third aspect can be realized. In the invention according to claim 7,
If the recording paper fed after recording on one side or both sides is a blank recording sheet on both sides, the print data of the subsequent page is read from the data storage means and recorded, and recorded on only one side. When the recording paper is turned upside down and returned to the recording position, the corresponding print data on the other side is read out from the data storage means and recorded on the other side of the recording paper, so that it is used as a printer. Also in this case, the same effect as the third aspect can be realized. According to the invention of claim 8, in the invention of claim 7, the print data of each page is bitmap-developed in a preset recording order, so that only one page of the print data is bitmap-developed immediately before recording. All right,
Therefore, the memory capacity can be reduced. According to the ninth aspect of the present invention, in the invention of the seventh aspect, the print data is transferred from the host device to the double-sided recording device for each page in a preset recording order.
The memory capacity can be further reduced.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory diagram of a double-sided copying machine showing a first embodiment of the present invention.

FIG. 2 is an operation flowchart of the double-sided copying machine showing the operation of the first embodiment of the present invention.

FIG. 3 is a block diagram of a main part of a control system of the duplex copying machine according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of a duplex copying machine showing a second embodiment of the present invention.

FIG. 5 is an operation flowchart of a duplex copying machine showing a second embodiment of the present invention.

FIG. 6 is a configuration explanatory view of a double-sided copying machine showing a third embodiment of the present invention.

FIG. 7 is a configuration explanatory view of a double-sided copying machine showing a fourth embodiment of the present invention.

FIG. 8 is an explanatory diagram illustrating a configuration of a double-sided copying machine according to a fifth embodiment of the present invention.

FIG. 9 is a block diagram of a main part (control system) of a double-sided copying machine showing a sixth embodiment of the present invention.

FIG. 10 is an operation flowchart of a duplex copying machine according to a sixth embodiment of the present invention.

FIG. 11 is a block diagram of a main part of a duplex recording apparatus according to a seventh embodiment of the present invention.

FIG. 12 is an explanatory diagram of a print system according to a seventh embodiment of the present invention.

FIG. 13 is an explanatory diagram of a configuration of a two-sided copying machine as an example of the related art.

FIG. 14 is an operation flowchart of a two-sided copying machine as an example of a conventional technique.

FIG. 15 is another operation flow chart of the duplex copying machine as an example of the related art.

[Explanation of symbols]

1 Document feed tray, 2 Automatic document feeder, 3 Document retractor, 4 Discharge / reversing roller, 5 Document exit, 6
Paper cassette, 7 developing section, 9 reversing stack section, 10
Output tray, 12 Copy control unit, 13 Document transport control unit, 14
Document evacuation / reversal unit, 16 image memory, 21 host interface unit, 31 transfer unit

Claims (9)

[Claims] 1. A double-sided copying machine provided with an automatic document feeder for copying images of a plurality of originals on both sides of a recording sheet, the first original having the first original recorded on one side. A document retracting unit for retracting the second document while the recording paper is turned over and returning to the sheet feeding side; a document transport unit for transporting the document in the document retracting unit to a reading position;
After the copying of the first document is completed, the second document is retracted to the document retracting section, and the recording of the third document is performed on one side of the second recording sheet. On the other side of the returned first recording paper, the second document conveyed to the reading position by the document conveying means is recorded, and subsequently,
A double-sided copying machine, comprising: copy control means for recording a fourth document on the other side of the second recording sheet that has been reversed and returned. 2. A double-sided copying machine having an automatic document feeder for copying a plurality of double-sided originals on both sides of a recording sheet, retracts the original having been read on one side only, reverses the original, and re-feeds the original. And a document evacuation / reversing section for copying one side of the first document onto one side of the first recording sheet, and then retreating the original to the document evacuation / reversing section to copy the second document. One side is copied onto one side of a second sheet of recording paper, and the second original is retracted to the original retracting / reversing unit while the first original is turned upside down and read from the original retracting / reversing unit. To the other side of the first sheet of recording paper that has been turned upside down and returned, and then re-fed the second original, which has been turned upside down, from the original retracting and reversing section to the reading position. Copy control means for making a copy on the other side of the second recording paper which has been reversed and returned And a double-sided copying machine. 3. The double-sided copying machine according to claim 1, wherein the document retracting unit or the document reversing unit is configured so that a plurality of documents can be retracted, and the document retracting unit is arranged in a retracted order. Alternatively, a double-sided copying machine, wherein the copy control means is configured to convey the document from the document reversing and reversing section to the reading position. 4. The double-sided copying machine according to claim 3, wherein the document reversing and reversing section is provided with a retreat paper path having a total length of a plurality of documents to be retreated. Double-sided copier. 5. A double-sided copying machine according to claim 3, wherein said document reversing and reversing section holds a plurality of documents to be retracted in an overlapping manner, and separates and retrieves the documents one by one in the order in which they are retracted. A two-sided copying machine characterized by having a configuration provided with. 6. A double-sided copying machine equipped with an automatic document feeder for copying a plurality of double-sided originals on both sides of a recording sheet, and original reading means for simultaneously reading images from both sides of the original, and reading by the original reading means. An image storage means for storing image information; and a subsequent original if the recording paper fed after reading from both sides of the original and recording on one side of the original is completed is blank on both sides. When the recording paper recorded on only one side is turned over and returned to the recording position, the corresponding image information on the other side is read. And a copy control unit for reading the image data from the image storage unit and recording the read image on the other surface of the recording paper. 7. A double-sided recording device capable of recording on both sides of recording paper in accordance with print data from a host device, a data storage means for storing print data sent from the host device, and one surface of the recording device. Alternatively, if the recording paper fed after the completion of recording for both sides is blank recording paper on both sides, the print data of the subsequent page is read from the data storage means and the recording for the print data is performed, and only one side is recorded. When the recording paper recorded on the recording paper is turned upside down and returned to the recording position, print control means for reading out the corresponding print data of the other side from the data storage means and recording it on the other side of the recording paper. , A double-sided recording device. 8. The double-sided recording apparatus according to claim 7, wherein the print data of each page of the document is developed into a bitmap in a preset recording order. 9. A print system comprising a host device and a double-sided recording device capable of recording on both sides of recording paper in accordance with print data from the host device, wherein print data sent from the host device is stored. If the recording paper fed after recording on one side or both sides is a blank recording paper on both sides, the print data of the succeeding page is read out from the data storage means and When the recording is performed, and the recording paper recorded on only one side is turned upside down and returned to the recording position, the corresponding print data on the other side is read from the data storage means and the other side of the recording paper is read out. And a print control means for recording data on the surface of the double-sided recording device. A print system comprising a transfer unit for transferring data to a recording device in a host device.