JPS60250366A - Recording device - Google Patents

Abstract

PURPOSE:To cope automatically with a sampling request without exerting an influence on a recorded medium by sampling and printing the first even page after a sampling request signal in case of a double side recording, and discharging it to the second loading means. CONSTITUTION:In accordance with a sampling request, a CPU3-3 checks the contents of a printing register group 3-19, and releases a register of a group 3-19 corresponding to the first even page after a sampling request signal. As a result, printing of its even page executed prior to an odd page is executed by a printing device 3-6, also a carrying path of the device 3-6 is controlled through the CPU 3-3 and a recorded medium brought to sampling and printing is discharged to an auxiliary tray, and also a page brought to sampling and printing by the CPU3-3 is reprinted to the next even page. Accordingly, this device can cope with a sampling request satisfactorily and automatically without causing a disorder of the page and without exerting an influence on the recorded medium.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a recording device configured to perform double-sided recording.More specifically, the present invention relates to a recording device configured to perform double-sided recording. This constitutes a double-sided recording device in which the paper is ejected.

[Prior art 1#] In a recording apparatus that prints or copies on a sheet-like recording medium, there is a demand for checking a recorded sheet by hand in order to check the recording state and confirm the recorded contents.

However, taking out the recorded sheets from the stack while recording a large amount of media disturbs the page consistency, number of recorded sheets, etc. between the recorded sheets, so A single-sided recording device has been put into practical use, which is equipped with a separate output section and outputs a recorded sheet for checking in addition to the original output.

In addition, the recording and ejection timing for the above-mentioned checked product cooperation sheet-like recording medium is before the start of recording.

It would be extremely inconvenient if it was limited to the recording stop state or recording interruption state such as after the end of recording, so there is a strong demand for an extremely simple operation such as simply pressing a button during normal recording. .

Furthermore, in conventionally known double-sided recording devices,
Since the page order pattern for recording is strictly determined, it is not possible to sufficiently meet the demand for recording on a check sheet-like recording medium during recording and discharging it to a sub-loading means different from the original sheet-loading means. Ta. Alternatively, even if such a request can be met, in order to recover from the disturbance in the page order pattern of recording caused by the sheet-like recording medium for checking not being ejected to the original loading means, it is necessary to dispose of the sheet-like recording medium, It was necessary to re-record the pages corresponding to the discarded sheet-like recording medium. As a result, more sheet-like recording media than are needed for checking are discarded, resulting in not only unnecessary waste but also an unnecessarily reduced throughput.

[Objective] In view of the above-mentioned points, the first object of the present invention is to automatically respond to requests for recording and ejecting a check sheet-like recording medium during double-sided recording, thereby affecting the recorded medium. An object of the present invention is to provide a recording device that is configured to avoid such problems.

Furthermore, a second object of the present invention is to provide a recording apparatus configured to minimize reduction in throughput due to recording and ejection of a check sheet-like recording medium during double-sided recording.

In order to achieve this object, the present invention provides a recording apparatus capable of double-sided recording, which includes a control means for recording and discharging a check sheet-like recording medium with a predetermined page relationship. .

Example Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a sheet conveying system of a double-sided printing apparatus which is an embodiment of the present invention. In this figure, 1-1 is the paper feed section, ■-
2 a pre-transfer conveyance path; 13 a drum for forming a toner image to be transferred onto the surface of a sheet of paper using known electrophotographic technology;
1-4 is a transfer charger that transfers the toner image on the drum 1-3 onto a sheet of paper, 1-5 is a conveyance path before fixing, and 1-8 is a transfer charger that transfers the toner image transferred onto the sheet of paper by heat and pressure. A fixing device for fixing, 1-7 is a shelf feeding path after fixing, 1-8 is a reversing parallel branching mechanism that branches a sheet conveying path, 1-8 is a pre-reversing conveying path, and 1-10 is a sheet conveying path. 3 known methods for reversing the front and back
A reversing mechanism using this roller, l-11 is a pre-reversing conveyance path, 1-12 is a pre-stacker conveyance path, 1-13 is a stacker,
1-14 is a stacker front branching mechanism, and 1-15 is an auxiliary tray.

During screen printing, sheets fed from the paper feed section 1-1 are conveyed to the drum 1-3 via the pre-transfer conveyance path 1-2. Then, the toner image formed on the drum]-3 using a known electrophotographic technique is transferred to a transfer charger! - transferred onto the sheet by corona discharge at 4;
The image is transported to the fixing device 1-8 via the pre-fixing transport path 1-5. After the image has been fixed on the first side in the fixing device l-8, the paper is conveyed via the post-fixing conveyance path 1-7, passes through the pre-inversion branching mechanism 1-8 and the pre-inversion conveyance path 1-9, and then is transferred to the inversion mechanism. 1-
Sent to 10.

The single-sided printed sheet that has been reversed in the reversing mechanism 1-1O is sent to the pre-transfer transport path 1-2 via the post-reversal transport path 1-11, where it is transferred to a drum 1-3 and a transfer charger 1. −
4, image transfer on the back side (second side) is performed in the same way as in the previous one-sided printing. Thereafter, it is sent to the fixing device be via the pre-fixing conveyance path 1-5, where the image on the second side is fixed. At this point, double-sided printing is complete.

The double-sided printed sheet is transferred from the post-fixing conveyance path 1-7 to the pre-reversal branching mechanism 1-8. The materials are loaded onto the stacker 1-13 via the pre-stacker transport path 1-12 and the pre-stacker branching mechanism 1-14.

The operation for double-sided printing on a single sheet is as described above, but in reality, if you wait for the completion of double-sided printing on one sheet before starting printing on the next sheet, the conveyance path will be Due to the considerable length compared to the sheet length, a reduction in throughput occurs.

Therefore, in order to obtain the same throughput as when printing on one side (that is, the number of pages that can be printed within a unit time), it is necessary to pass the sheets through drums 1-3 at the same intervals as when printing on one side. . As a method for realizing such a function, in the present embodiment shown in FIG. 1, the time interval between feeding sheets from the paper feeding section 1-1 is set to be twice the interval during one-sided printing. Furthermore,
In this embodiment, after finishing printing on one side, the reversing mechanism 1-
When the sheet reversed by 10 flows into the pre-transfer transport path 1-2 from the post-reversal transport path 1-11, the unprinted paper immediately after being sent from the paper feed section 1-1 and the unprinted paper are separated. Configure it to be exactly in the middle.

By operating in this way, the pre-transfer conveyance path 1-2
From drum l-3, transfer charger l-4, pre-fixing conveyance path 1
-5. Fixing device 1-6. In the conveyance path from the fixing support conveyance path 1-79 to the reversal direction branching mechanism 1-8, sheets with already printed on the back side and sheets with printing only on the first side flow alternately. .

The pre-reversal branching mechanism 1-8 branches alternately arriving double-sided printed sheets and single-sided printed sheets to the pre-stacker transport path 1-12 or the pre-reversal transport path 1-8, respectively. .

In this case, the pre-transfer conveyance path 1-2. Drum 1-3. Pre-fixing conveyance path 1-5. Fixing device 1-6. Fixing support feed path 1-79 Reverse direction branching mechanism 1-89 Anti-reverse direction feed path 1-81 Reversing mechanism 1
-10. The length of one conveyance loop consisting of the conveyance paths 1-11 after reversal must be an odd number multiple of the sum of the length of the sheet in the conveyance direction and the interval between the sheets. If it is an even number, the sheet fed from the paper feed section 1-1 and the sheet from the post-reversal conveyance path 1-11 overlap on the pre-transfer conveyance path 1-2. This causes the inconvenience of being lost.

In other words, after the first side of a certain sheet arrives at the position of drum 1-3, the second side of that sheet returns to the position of drum 1-3 again on the odd-numbered side. It is.

In this embodiment described above, the spacing between both sides of the sheet (i.e.,
A sheet of paper that has finished printing on the first side is returned to drum 1-3.
The number of sheets to return to and print on the second side corresponds to after passing through drums 1-3)
Let be N. Therefore, for example, when ni = 5, after the first side is printed, a new 4
You will have to print one sheet.

Further, when printing only on one side, it is necessary to stack the sheets on the stacker 1-13 with the printed side facing down in order to maintain the correct page order of the sheets.

On the other hand, when printing on both sides, it is necessary to stack the paper with the second printed side facing down. That is, in order to properly arrange the page order during double-sided printing, it is necessary to print the later page first among the pages to be printed on both sides of a certain sheet. If printing starts from the first page, even-numbered pages will be printed before odd-numbered pages.

FIG. 2 is a schematic diagram showing the conveying system shown in FIG. 1 and the state of the sheets flowing thereon when the distance between both sides is 5. In this figure, the reversing mechanism 1-10 is schematically represented as "a section through which a sheet is reversed". 2-1 is a sheet transport loop;
-2-1 to 2-2-5 are sheets being conveyed.

Here, the numbers without parentheses written on both sides of each sheet are the page numbers printed or currently being printed on that side, and the numbers in parentheses indicate the page numbers to be printed.

In FIG. 2, unhatched sheets 2-2-2 and 2-2-4 have not yet been reversed, and hatched sheets 2-2-1 and 2-2-3 indicates an inverted wave. Further, the sheet 2-2-5 which is partially hatched indicates that it is currently being reversed by the 1-reversing mechanism 1-10.

FIG. 3 shows a schematic diagram of an offline printing system to which the present invention is applied.

In this figure, 3-1 is a magnetic tape (hereinafter abbreviated as MT) on which print information, control information, etc. are recorded, and 3-2 is MT3-1.
3-3 is a central processing unit (hereinafter abbreviated as CPU) that controls the entire system; 3-4 is a page that stores the print information of each page for each page; Buffer 3-5 is a page buffer 3 under the control of CPU 3-3.
3-6 is a printing device that performs actual printing; 3-7 is a management register group consisting of a plurality of registers that stores various information necessary for printing each page; 8 is a separation register group that separates the page information of each page sequentially created on the page buffer 3-4 into pages printed on the front side and pages printed on the back side of the paper during double-sided printing; 3-9 is a group of print registers that control the order of the sides to be actually printed; 3-10 is a page pointer indicating the register set last among the management registers 3-7; and 3-11 is a register in the page buffer 3-4. 3-12 is a page number counter indicating the number of pages created in the current printable page; 3-12 is a separate register group 3-8, and when new page information is created, the page information is stored. Separate set pointer indicating the register to be set; 3-13 a separate read pointer indicating the register corresponding to the page currently being printed among the separate register group 3-8; 3-14 a separate read pointer indicating the register of the print register group 3-8. Among them, a print pointer indicating the register corresponding to the side currently being printed, 3-15 a print counter indicating the number of registers corresponding to the side to be printed among the print register group 3-9, 3-16 a double-sided Double-sided spacing register for registering spacing K.

3-17 is a copy number register for registering the number of copies (that is, it indicates how many copies of the same page are to be printed consecutively), and 3-18 is a register that indicates how many copies of the same page have been printed at present. 3-18 is the copy number counter shown, and 3-18 is the check sheet printing and auxiliary tray 1.
3-20 is a sample flag register that stores the fact that a sample print request has been made.

FIGS. 4(1) to 4(3) show the relationships and structures of registers, pointers, etc. shown in FIG. 3.

Here, the contents of each register included in the management register group 3-7 (see FIG. 4 (1)) are as follows: (1) Page existence flag 3-7 indicating whether page information of the page indicated by the register exists. -1, ■ Page buffer pointer 3-7- indicating the position on the page buffer occupied by the page indicated by the register
2. Other information necessary to print one page.

The contents of each register included in the separated register group 3-8 (see FIG. 4 (2)) are separated management pointers 3-8- representing the registers in the management register group 3-7 corresponding to the page indicated by the register. It is 1.

The contents of each register included in the print register group 3-9 (see Figure 4 (3)) are: ■ Print flag 3-9-1 indicating whether or not to print the side indicated by the register; Print management pointer 3-13 indicating a register in management register group 3-7 that has corresponding page information
-2, ■ When printing multiple copies of one page in succession, a part number counter 3-9-3 that indicates which copy the side indicated by the register is (i.e., its part number), [stock] Page index 3 - indicates whether the side indicated by the register is an even-numbered page (i.e., the side to be printed first) or an odd-numbered page (i.e., the side to be printed for the second time).
It is 9-4.

Note that this index is alternately "even" and "odd" (that is, even numbered pages and odd numbered pages) in each register of the print register group 3-8.

The page buffer 3-4 is divided into a plurality of page buffers each corresponding to one page (Fig.
)reference). Furthermore, each register in the management register group 3-7 corresponds to each partial buffer of the page buffer, and the page buffer pointer 3-7 takes this correspondence.
7-1 (see Figure 4 (1)).

The page buffer 3-4 and the management register group 3-7 store the information necessary to print one page, but it is not necessary to separate these 3-4 and 3-7; It is also possible to place various information in the page buffer. However, if the page buffer cannot be placed in the main memory due to memory capacity limitations, the page buffer, which requires a large amount of space, can be placed on a large-capacity secondary storage medium (such as a magnetic disk). It is also possible to deal with this by placing the management register group on the main memory.

The page information created on the page buffer 3-4 based on the information read from the MT 3-1 includes the first page,
They are created consecutively, such as the second and third pages. However, as in this embodiment, when the sheet of paper is printed on the first side,
In a system in which sheets are alternately printed on the second side, the order of the pages to be printed is not consecutive.

Therefore, a means to absorb and adjust this difference is required. The separation register group 3-8 and print register group 3-8 shown in FIG. 3 serve as this adjustment means. In other words, the separate register group 3-8 divides the pages created in order in the page buffer 3-4 (and the management register group 3-7) into even pages (i.e., pages printed on the first side).
and odd pages (i.e. pages printed on the second side)
It plays the role of separating the On the other hand, print register group 3-8
serves to adjust the order of pages to be printed in a predetermined sequential pattern required for duplex printing.

In order to adjust the printing order, the print register group 3-9 uses a transport loop (2-9 shown in FIG. 2) during double-sided printing.
1) Simulate the above sheet page (both sides). The print register indicated by the print pointer 3-14 indicates the page currently being printed (see the third page on the sheet 2-2-3 shown in FIG. 2), and the print register indicated by the print pointer 3-14 is displayed. Switching is performed sequentially to correspond to the movement of paper on the conveyance loop.

Then, the order of pages on the print register group 3-8 is set as the order of pages to be printed.

Prior to printing, each register group, pointer, and counter are first initialized. FIG. 5 shows a flowchart of initialization.

First, set the page presence/absence flag 3-7-1 of the management register you are currently focusing on to "None" (Step 5-1)
Then, various information in the management registers is initialized, and this is repeated until initialization is completed for all management registers (step 5-3.5-4).

In steps 5-5 to 5-7, all of the print flags 3-111-1 of each register in the print register group 3-8 are set to "non", and the part number counter 3-8-
Set all 3 to rlJ. Also, page index 3-1
11-4 is correctly set so that even (even numbered pages) and odd (odd numbered pages) alternate.

In steps 5-8, appropriate registers in the management register group 3-7 are correctly set in the page pointer 3-10.

In step 5-8, the page number counter 3-11 and print counter 3-15 are set to zero.

In step 5-10, among the registers in the separated register group 3-7, the register that should be set first in creating the print information for the first page is set in the separated set pointer 3-12.

Step 5-I! Now, among the registers in the separation register group 3-8, the register next to the register set as an initial value in the separation set register 3-12 is set in the separation read pointer 3-13. That is, this sets the register corresponding to the second page.

In step 5-12, among the registers in the print register group 3-8, the register corresponding to the side to be printed on the sheet first is set in the print pointer 3-14 as an initial value. This register must be a register for even numbered pages (ie, page index 3-111-4 is "even").

In step 5-13, a double-sided spacing M determined depending on the size of one sheet is set in the screen spacing register 3-16.

In step 5-14, the copy number counter 3-18 is set to 1.
Set.

In step 5-15, sample flag register 3-2
Set "None" to 0 and complete the initialization.

After completing the initialization in this way, the CPU 3-3 starts creating a page.

FIG. 6 is a flowchart showing the procedure for creating a page.

In condition determination steps 6-1 and 6-2, new pages are not created in the page buffer for pages that have not yet been printed.

In condition determination step 6-3, it is determined whether page creation is complete.

If there is data on the MT3-1, the CPU 3-3 reads the information on the MT3-1 via the device 3-2 (step 8-4), analyzes this, and sets the page buffer pointer 3 of the management register. -7-2 (Page pointer 3-1
Create page information in the page buffer indicated by (specified by 0). Here, creating page information means registering print information on the page buffer and setting the page presence/absence flag 3-7-1 of the corresponding management register to "present".

Next, in step 6-5, the page number counter 3
-11 is updated.

Furthermore, in step 6-6, the page pointer 3-10
The management register indicated by is set in the separate register indicated by the separate set pointer 3-12. This means that the currently created page is registered in the separate register group 3-8.

In step 6-7, the separate set pointer is updated.

In steps 6-8 and 6-8, the management register for creating the next page information is searched. That is, while advancing the page pointer 3-10 one by one, the page presence/absence flag 3-7-1 of the management register is checked, and this is repeated until the first management register whose page presence/absence flag is "none" is found. After this, the control returns to step It-1 again.

Furthermore, if it is determined in step 6-3 that the printing information on MT 3-1 has been completed, control is shifted to determination in step θ-11.

In step 6-11, it is checked whether the current page is an odd-numbered page or an even-numbered page from the relative positions of the separation set pointer and the separation read pointer, and if it is an odd-numbered page, page creation is ended. If it is an even page, control is transferred to step 8-12.

Here, the separate read pointer always points to an even page. . Therefore, if the relative position of the one-separation read pointer and the separation set pointer (how far the latter is ahead of the former) is an even number, the page pointed to by the separation set pointer is also an even page, and therefore the current page is an odd number. Furthermore, if the relative position is an odd number, the current page is an even number.

In step 6-1-2, completely blank page information is created in the page buffer indicated by the page pointer 3-10. The process of step 6-12 means that when the print information of MT 3-1 ends at an odd page (k page), a dummy page is created on the next even page (k+1 page).

In this embodiment, even-numbered pages are printed before odd-numbered pages, and paper is fed when even-numbered pages are printed. Therefore, if there is no dummy (k+1 page) to be printed in advance, the sheet on which page k+1 is to be printed will not be fed. That is, for page k, although a toner image is formed on the drum 1-3, there is no paper to transfer it to, so as a result, the page is not printed.

Judgment in step 6-11 and step 8-1
By the processing in step 2, even if the print information on the MT 3-1 ends with an odd numbered page, the above-described page omission can be prevented by creating a dummy even numbered page. Further, if the last page is an even numbered page, printing up to the last page can of course be performed correctly.

If it is determined in steps 8-1 to 8-2 that page creation is not possible, the process enters a waiting state in step 6-10. This suspends page creation only while one page is being printed, thereby preventing unprinted pages from being destroyed by newly created pages.

Note that, prior to printing, the CPU 3-3 creates an "L" page. This is a measure to absorb the difference between the order of pages created in this embodiment and the order of pages printed. Then, after page creation is completed, printing of the page is started. This rLJ indicates the reference value in the condition determination step e-1, that is, the total number of page buffers in the page buffer 3-4 (and the total number of each management register included in the management register group 3-7).

FIGS. 7(1) and 7(2) show a schematic flowchart of the printing procedure.

In step 7-1, copy number counter 3-18
Set 1 to 1 to initialize.

In step 7-2, the print management pointer 3-. of the print register specified by the print pointer 3-14 is selected. 9-2, set the contents of the separation management pointer 3-8-1 in the separation register specified by the separation read pointer 3-13, and set the copy number counter to the part number counter 3-8-3 of this print register. Set the value of 3-18 and print flag 3-! of the print register. Set 3-1 to "possible".

In step 7-3, 1 is set in the print counter 3-15.

As described above, in steps 7-1 to 7-3, the first side of the page to be printed first (second page) is set in the print register.

In step 7-4, the CPU 3-3 selects the print flag 3-9-1 of the print register indicated by the print pointer 3-14.
is checked, and if it is "possible", it is determined that the side corresponding to this print register is printable and printing is performed (see step 7-5 onwards).

In step 7-5, the CPU 3-3 selects the print management register 3-9 of the print register indicated by the print pointer 3-14.
-2 to find the management register of the page to be printed, and check the page presence/absence flag 3-7-1 in that management register. If the result is "Yes", it is determined that there is a page to be printed, and printing is performed from step 7-6 onwards.

In step 7-6, the CPU 3-3 selects the print management register 3-1 of the print register indicated by the print pointer 3-14.
The management register is read from 1-2, and the page buffer (that is, the page to be printed) indicated by the page buffer pointer 3-7-2 is obtained. And printing hardware 3-
5 and printing device 3-6 appropriately to print one sheet (single-sided).
Print. Also, printing itself is performed by CPU3-
3, the page creation procedure is executed until printing of one page (single-sided) is completed.

When printing of one sheet (single side) is completed, control is switched to step 7-
Move to 7.

In step 7-7, the CPU 3-3
Based on the signals from 6 and the like, it is checked whether printing has been performed normally or not, and if printing has been performed normally, control is transferred to step 7-8.

In step 7-8, the CPU 3-3 examines the contents of the sample flag register 3-20 to check whether there is a sample print request that has occurred during printing. If there is no sample print request, control is transferred to step 7-8.

In step 7-8, the print flag of the print register indicated by the print pointer 3-14 is set to "non-J".

In step 7-10, the value of the print counter is decremented by 1, i.e. the step ? -9 and 7-
In IO, the print register corresponding to the side printed in step 7-6 is opened.

In step 7-11, the value of part number counter 3-11-3 in the print register indicated by print pointer 3-14,
The value of copy number register 3-17 is compared. If they match, it is determined that printing has been completed for all copies of that page, and step 7-12
Control is transferred to the page buffer γ release.

In step 7-12, the print management pointer 3-9-2 of the print register indicated by the print pointer 3-14 is set to the management register of the page that has just been printed, and the page existence flag 3-7-1 is set to "None". Set to .

Step? -13, the value of the page number counter 3-11 is decremented by 1. Steps 7-12 and 7- as described above
The page buffer for which printing has been completed is released by the process in step 13, and a new page can be created in that page buffer in the page creation procedure.

Step? -14, check the page index 3-3-4 of the print register indicated by the print pointer 3-14, and
If so, control is transferred to step 7-15.

In step 7-15, information about the odd-numbered page that is the back side of the even-numbered page that has just been printed is set in the print register (details will be described later).

In step 7-16, the value of print counter 3-15 is incremented by one.

In step 7-17, copy number counter 3-1
Set 8 to 1 and initialize it.

In step 7-18, the second separation register counting from the currently indicated separation register in the page set direction is set for the separation read pointer 3-13. Since the separate read pointer 3-13 has already indicated an even page in step 5-11 of the initialization procedure shown in FIG.
By the procedure shown in step 7-18, the separate read pointer 3-13 always indicates an even page.

In step 7-18, the separation management pointer 3-8 is read in the separation register specified by the separation read pointer 3-13.
-1 (that is, corresponding to the even page to be printed next), and set the page presence/absence flag 3-
Check 7-1. If "Yes", the next even-numbered page to be printed has already been created on the page pant γ, so this even-numbered page is set in step 7-20 and subsequent steps.

In step 7-20, information on the even page to be printed next is set in the print register based on the separation read pointer 3-13 and the copy number counter 3-18.

In step 7-21, the value of the print counter is incremented by 1 corresponding to the page set in the print register in step 7-20.

In step 7-22, set the print pointer 3-14 to 1.
, and set the next print register.

In step 7-23, the value of the print counter 3-15 is checked, and if it is not zero, there are still surfaces to be printed, and the control is returned to step 7-4.

In step 7-4, if the print flag 3-11-1 of the print register indicated by the print pointer 3-14 is "non", control is changed to step? -Move to 32.

In step 7-32, one blank print is performed.

Here, "blank printing" means interrupting printing for only the time required to print one page, or printing one completely blank page. Note that during blank printing, paper is not fed even if the page indicated by the print pointer 3-14 is an even page. Also, CPU3-
Step 3 executes the page creation procedure during blank printing as well as during printing in step 7-6.

In step 7-5, if the number of pages to be printed is "none", control is shifted to step 7-28.

In step 7-28, one blank print is performed.

Step? -28, the CPU 3-3 reads the double-sided spacing from the double-sided spacing register 3-16, and counts X in the printing direction from the print register indicated by the print pointer 3-14.
The print flag in the print register of the th print register (that is, the back side of the even-numbered side that is currently printed or blankly printed) is set to "non".

In the double-sided printing according to this embodiment, printing of even-numbered pages precedes printing of odd-numbered pages. Therefore, only even-numbered pages are left blank due to reasons such as not being able to create the page in time.

In step 7-30, the contents of the print register indicated by the print pointer 3-14 (print flag 3-!If-1. print management pointer 3-9-2, part number counter 3-8-3)
is copied to the second print register (that is, the next even-numbered side to be printed) counting in the printing direction. This means that even-numbered pages that could not be printed because the pages are "null" will be printed during the next even-numbered copy printing.

In step 7-31, the print flag 3-fl-1 of the print register indicated by the print pointer 3-14 is set to "non".

In step 7-30, page information is set, and step ? Since the print register is released at step -31, the value of the print counter 3-15 is set at steps 7-28 to 7-31.
There is no change in this.

If printing ends abnormally, the control returns to step 7-29.
(Step 7-7).

Furthermore, if the sample flag register 3-20 is "present", then it is determined whether the printed page is an even numbered page or an odd numbered page using the same procedure as step 7-14, and if it is determined that it is an odd numbered page, , control is transferred to step 7-8.

If it is determined that the page is an even numbered page, processing necessary for sample printing is performed, and control is transferred to step 7-28 (step ?-8) (this step will be described in detail later).

Copy number of the printed side (value of copy number counter 3-11-3 in print register indicated by print pointer 3-14)
is smaller than the value of the number of copies register 3-17, the predetermined number of copies of that page has not yet been printed, and control is transferred to step 7-24 (step ?-).
11).

In step 7-24, the page index 3-9-4 of the print register indicated by the print pointer 3-14 is checked, and if it is "even", control is passed to step 7-25.

In step 7-25, the odd-numbered pages on the back side that have just been printed are set using the same procedure as step 7-15.

In step 7-28, the value of print counter 3-15 is incremented by one.

In step 7-27, a value obtained by adding 1 to the copy number of the printed side is set in the copy number counter 3-18.

In steps 7-14 and 7-24, if the printed page is an odd numbered page (i.e., the print pointer
The page index 3-9-4 of the print register indicated by -14 is "
If it is determined that the
Transfer control to

More steps? -19, if it is determined that the next even-numbered page to be printed is "none"? −
Control is transferred to 22. This means that since the next even-numbered page has not yet been created, that page is not set in the corresponding print register.

In step 7-23, if it is determined that the value of the print counter 3-15 is zero, the print register l\3
There are no more pages to print on -8, so printing ends.

FIG. 8 shows a detailed flowchart of the single-sheet printing procedure in step 7-6 shown in FIG. 7, in which paper feeding is performed only for printing even-numbered pages.

In step 8-1, the management register of the page to be printed is read from the print management pointer 3-9-2 of the print register indicated by the print pointer 3-14.

In step 8-2, the page/header indicated by the page header pointer 3-7-2 of the management register obtained in step 8-1 is instructed to the printing hardware 3-5.

In step 8-3, the CPU 3-3 issues a print command to the printing hardware 3-5 and printing device 3-6.

In step 8-4, the printing hardware 3-5 transfers the print information (for one page) on the page buffer γ instructed in step 8-2 to the printing device 3-6, and
-6, this transferred print information is printed.

Since the printing hardware 3-5 and the printing device 3-6 operate autonomously while printing one page, the CPt13-3
executes the page creation procedure for this one page during printing, and returns to the printing procedure in response to the one page printing completion signal from the printing device 3-6.

FIG. 8 shows steps 7-15 and step ? shown in FIG. -25 (the contents of both steps are the same), and shows in detail the procedure for setting odd page information to the print register.

In step 8-1, the double-sided spacing M is obtained from the double-sided spacing register 3-16.

In step 8-2, the Nth print register (the register corresponding to the odd-numbered page on the back side of the even-numbered page just printed) is set as counted in the printing direction from the position indicated by the print pointer 3-14.

In step 8-3, the contents of the separate register one before the separate register indicated by the separate read pointer 3-13 (that is, the position of the management register corresponding to the odd-numbered page on the back side of the even-numbered page just printed) are transferred to the step 8-3. Set the print management pointer 3-9-2 of the print register set in step 8-2.

In step 8-4, the value of part number counter 3-11-3 in the print register indicated by print pointer 3-14 is set to N.
The part number counter 3-9-3 in the print register 3-9-3 is set.

In step 9-5, the print flag 3''9-1 in the Nth print register is set to "possible".

Figure 10 shows the steps shown in Figure 7? -20 (detailed flowchart of the procedure for setting even page information to the print register).

In step 10-1, the second print register counted in the printing direction from the position indicated by the print pointer 3-14 (that is, the register corresponding to the even-numbered side (first side) to be printed next to the even-numbered page just printed) I put it on.

In step 10-2, the contents of the separation register indicated by the separation read pointer 3-13 (that is, the position of the management register of the next page to be printed) are transferred to the print management pointer 3-1 in the second print register previously set. Set it to 9-2.

In step 10-3, the value of the copy number counter 3-18 is changed to the copy number counter 3-1]-3 of the second print register.
Set to .

In step 10-4, the print flag 3-8-1 in the second print register is set to "possible".

FIG. 11 shows step 7-28 and step ? shown in FIG. -32 (blank print execution procedure) is shown in detail.

In step 11-1, the CPU 3-3 instructs the printing hardware 3-5 and printing device 3-8 to print a blank page. Then, in step 11-2, a blank page is printed, and the CPU 3-3 executes a page creation procedure.

In the printing procedure of this embodiment described above, if printing on one side of an even page is completed normally, after opening the print register corresponding to that side (steps 7-8
and step 7-10), the odd numbered page corresponding to the reverse side of the side just printed (see step ?-15, 7-I8 and step ?-25.7-28), and the even numbered page after the side just printed (see step ?-15, 7-I8 and step ?-25.7-28). Step ?-20.7-21) is set in the print register.

On the other hand, after printing on the first side of an odd-numbered page, the print register is released, but no cents are added to the print register.

The odd page setting procedure shown in steps 7-15 and 7-25 ensures that after printing an even page, the next sheet is printed with the odd page on the reverse side, and The page correspondence will be correct.

The procedure of steps 7-20 also ensures that even pages are printed in the correct page order. Therefore, step? -15/7-25 and step? -20
Through the page setting procedure, pages are set on the print register group 3-8 in the order of pages required for double-sided printing.

FIGS. 12(1) to 12(24) are schematic diagrams showing the state of double-sided printing according to this embodiment. Here, the rings equally divided radially by broken lines form the ring-shaped print register group 3-8,
The arrow represents the print pointer 3-14, and the center of the ring represents the print counter. Also, print pointer 3
The traveling direction (printing direction) of -14 is clockwise in this figure. The arrow indicates the print register indicated by the print pointer 3-14. Furthermore, the numbers in the ring-shaped print register group 3-9 represent the page numbers set in the print registers, and the numbers written in the center circle of the ring represent the value of the print counter 3-15.

Is Figure 12 (1) a step in Figure 7? -3 and 7-
4, that is, the state immediately after setting the first page (second page) in the print register;
(23) represents the state immediately before entering step 7-22, and (24) in the figure represents the state at the end of printing. Also, if the number in the ring is crossed out with a backslash (\,), this means that the page was printed immediately before and the print register was released. Furthermore, print registers with page numbers that are not erased with (\) are set to print flag 3.
-9-1 is "possible" and other print registers are "not"
It represents that.

In FIGS. 12(1) to (24), the distance between both sides x=5. The number of registers in print register group 3-9 is 10. Number of copies: 1.
The total number of pages is 18. This example shows a case where all pages are printed normally by normal printing (not sample printing). Each case will be explained in detail below.

FIG. 12(1) shows the state immediately after the second page to be printed for the first time is set.

Figure 12 (2) shows that the second page is printed (step 7-
6) and its print register is released (step 7-
9 and 7-10), the first page is the back of the second page.
page (see steps 7-15 and ?-16) and the second
The fourth page, which is the next even-numbered page, is set to the Nth page and the second page from the position of the print pointer 3-8, respectively (steps 7-4 to 7-21 are passed).

FIG. 12(3) shows the state immediately after printing one blank sheet (see step 7-33) after printing the second page.

In this embodiment, odd pages are printed for the first time when the sheet, on which even pages have been printed on the first side, has gone around the conveyance loop.

Therefore, for a while after printing starts, there is no sheet between even-numbered pages on which odd-numbered pages should be printed. In addition, in double-sided printing according to this embodiment, paper is fed for printing even-numbered pages, and the paper feeding interval is twice as long as that in single-sided printing (that is, every other page timing). Therefore, in the initial stage of printing, it is necessary to alternately repeat printing of even-numbered pages and blank printing. FIGS. 12(1) to 12(5) show the transient state at the initial stage of printing.

FIG. 12(7) shows the state after the first page, which is an odd numbered page, has been printed (see step 7-6) and its print register has been released (see steps 7-8 and 7-10). Step 7 through steps 7-4 to 7-14
-22 immediately preceding state).

12(6) to 12(17) show a steady state in double-sided printing, in which even-numbered pages and odd-numbered pages are printed alternately. At this time, the value of the print counter becomes 4 and 3 alternately (that is, after printing an even page, the value is 3 → 4).
．． After printing odd numbered pages, the number becomes 4 → 3).

FIGS. 12 (18) to (23) show transitional states at the end of printing.

In Figure 12 (18), after printing the last 18th page (see step 7-6) and opening the register (see steps 7-9 and 7-10), set the 17th page on the back side in the print register. (Steps 7-15 and 7-16
reference). Here, the 18th page is the final page, and according to the judgment in step 7-18, the next page is "
"No", so the 20th page is never set.

Paper feeding is not performed after FIG. 12 (18), and printing of odd-numbered pages and blank printing are performed alternately.

FIG. 12 (23) shows that the value of the print counter 3-15 becomes zero after printing the last odd-numbered page, the 17th page (that is, the back of the last page, the 18th page).
This shows the state where printing ends (12-24). Note that, as described in step 6-12 of the page creation procedure, the page buffer γ is used regardless of whether the last page of data is an odd or even number.
The final page created above is always an even numbered page.

Next, the number of print registers required in the print register group 3-8 will be explained. must be an even number.

FIG. 13 is a schematic diagram showing the state of the print register and print pointer 3-14 during the printing process, and shows the double-sided spacing x=7. The case where the number of print registers=10 is shown. In this figure, as in FIG. 12, the print register group 3-8 is represented by rings equally divided radially 17, and the print pointer 3-14 is represented by arrows. Further, the numbers in each section of the ring represent the page numbers set in each print register. Furthermore, when the page number is crossed out with a backslash (\), it means that the print register for that page has just been released. Among the print registers, the print flag 3-9-1 is "OK" for those with page numbers that have not been erased with backslashes.
All others represent "non". In order to distinguish between even and odd pages, only even page numbers are enclosed in angle brackets ([, ]).

The direction of movement (printing direction) of the print pointer 3-14 is clockwise. Further, the arrows shown outside the ring indicate the minimum range of print registers required at each point in time.

Furthermore, rM-1 ke'' shown on the outer periphery of the ring, rM+1
keJ, rM keJ', rM-1ke'' respectively indicate the number of print registers.

FIG. 13(1) shows a state in which a simple sentence page (the sentences are an even number) is being printed. At this time, the pages existing on the print register are odd-numbered pages such as the (u-M)th page, the (sentence-12)th page, ..., the (9th, -3)th page in addition to the simple sentence page. They are located at the 1st, 3rd, . . . , 12th positions counting from the text page in the printing direction. Therefore, the number of print registers required in this case is (t1).

Figure 13 (2) shows that the page (142) is printed after printing the simple sentence page.
), the second (Jlj-1) page counting in the printing direction.
) page is set in the Xth print register. At this time, the unprinted odd pages that need to be placed on the print register are the (sentence - M)th page, the (sentence - +2)
Page..., the (sentence-1)th page. Since these odd-numbered pages are set every other page on the print register, in order for these pages to exist on the print register at the same time, the number of print registers needs to be (M+1).

FIG. 13(3) shows a state in which the first page (k is an odd number) is being printed. At this time, the pages that should exist in print register 2 are page 1, page (k+2), and so on.

The (k+M-1)th odd page and the (k+N+)th page
2) It is a page. Therefore, in this case, the number of print registers needs to be M or more.

FIG. 13(4) shows the state after the first page is printed. Here, after opening the print register of the th page, the th (
k+2) page, (k+4) page, ..., (k+4) page,
Since there are an odd number of +M-1) pages and a (k+M+2)th page, the number of print registers required is N.

As is clear from the above explanation, print register group 3-9
The number of print registers may be an even number of M+1 or more with respect to the maximum double-sided spacing M1 (odd number).

Next, the number of page buffers required in the page buffer 3-4 will be explained using FIG. 13.

As shown in FIG. 13 (1), while printing a simple sentence page (the sentences are an even number), the print register contains the page (sentence-M), page (also-12), ..., page 1-3. ) pages (total (M-1)/2 pages) and simple text pages (M+1)/2 pages are set, and it is sufficient that this many pages exist on the page buffer.

As shown in FIG. 13 (2), after printing the second page and setting the (sentence+2)th page and the (cross-1)th page, the (u-M)th page, the (sL -G2) page..., the odd numbered page of the (G-1) page (total (
M-1)/2) and the (sentence + 2)th page (M+
1)/2+1 page is set on the print register. Here, for the simple sentence page, both the print register and the page buffer have just been released, and at this point, a new page has not yet been created on the page buffer where the simple sentence page existed. Also, the first
42) page (even number) exists, the (141)th page (odd number) also exists on the page buffer. Therefore, at the time shown in FIG. 13 (2), (M+1
) / 2 + 3 pages worth of page buffer is required.

FIG. 13 (3) G;: As shown in i, during the printing of page (k (k odd a)), the page 1,
The (k+2)th page, ..., the total of the (k+M-1)th odd numbered pages (total (M+1)/2 pages) and the (k10th M+2)th page is (M”l)/2+1 pages. exist.

Further, as in FIG. 13(2), since the (k+1)th page exists on the page buffer, the number of page buffers required is (841)/2 +2.

As shown in Figure 13 (4), after the first page is printed, the page is not opened in the second case (see Figure 13 (3))
Since this is the same as above, and a new page has not yet been created in the page buffer where the first page existed, the number of page buffers is (M+1)/2+2.

As is clear from the above explanation, the required minimum number of page buffers is (M + 1) for the maximum double-sided spacing M
/2 +3.

Next, the required minimum number of separate register groups 3-8 will be explained.

First, since a page set in a page buffer is always set in a separate register, the number of separate registers must be equal to or greater than the number of page buffers.

Now, the number of page buffers is n (n≧ (M+1)/2
+3), the required number of separate registers will be considered below.

The required number of separate registers is consecutive pages from the oldest page existing on the page buffer to the newest page on the page buffer (pages that have already been printed also remain on the separate register). In other words, for n9 minutes of the page buffer, the number of printed pages after the oldest page (even pages print before odd pages, so the oldest page is always an odd page) and the number of even pages in the page buffer release method is added.

In the cases shown in Figures 13 (1) and (2), the even-numbered pages before the simple sentence page are open pages, and the oldest page is the (1-M)th page (odd number), so the (u-M)th )
The number of even pages between the page and the (sentence-1)th page is (M-1)/2. Therefore, the number of separate registers required is n+(M-1)/2. To further explain this, it is as shown below.However, ga is a page that has already been printed and has been removed from the page buffer.

(odd) represents an odd numbered page.

Similarly, the cases of (3) and (4) in Figure 13 are expressed as 1
The result is as shown below.

Therefore, the required minimum number of separate registers is still 10 (M
-1)/2.

Next, a procedure to be followed when a sample print request is received during printing will be described.

When the operator operates the sample print request means 3-19, the sample print request means sets the sample flag register 3-20 to "present".

FIG. 14 shows the steps in step 7-8 shown in FIG.
3 is a detailed flowchart showing a procedure for responding to a sample print request.

In step 14-1, the CPU 3-3 reads the sample flag register 3-20 to check whether there is a sample print request. Sample flag register 3-20 is “
If "Yes", it means that there is a sample print request, and the control is shifted to step 14-2.

In step 14-2, the page index 3-9-4 of the print register indicated by the print pointer 3-14 is checked, and if it is "even", control is transferred to step 14-3.

In step 14-3, a sample print command is issued to the printing device 3-6. In the printing device 3-6, the sheet that has received the sample print command is not reversed or reprinted, but is immediately transferred from the pre-reversing branching mechanism 1-8 to the pre-stacker transport path 1-12. The paper is discharged to the auxiliary tray 1-15 via the pre-stacker branching mechanism.

In step 14-4, sample flag register 3-2
0 is set to "none" and control is transferred to step 7-28.

Step? -28, the print register of the odd numbered page that was scheduled to be printed on the second side of the sheet discharged to the auxiliary tray 1-15 in response to the sample print request is released. As a result, blank printing is performed at the timing when the odd-numbered page was scheduled to be printed. This corresponds to the fact that the sheet that was scheduled to be printed here is discharged as a sample print, and the second side is not printed.

Next, in step 7-30, the same even-numbered page to be sample printed is set in the print register for the next even-numbered side. As a result, even-numbered pages ejected to the auxiliary tray by sample printing are reprinted when the next paper is fed. Therefore, due to sample printing, pages may be missing (and pages may be out of order) in the output stacked on the stacker.
will not occur.

Step? -31, the print register of even-numbered pages to be sample printed is released.

In Stella 7', 14-1, if the sample flag register 3-20 is "absent", it means that there is no sample print request, and the control is then transferred to step 7-9.

In step 14-2, if the page index 3-11-4 of the print register indicated by the print pointer 3-14 is "odd" (in other words, the printed page is an odd numbered page), the control also returns to step 7-9. We do not transfer or print samples. Next, it will be described below whether such a problem would occur if sample printing of odd-numbered pages was not prohibited in step 14-2.

As described above, in this embodiment, printing of even-numbered pages precedes printing of odd-numbered pages.

Second, when printing odd-numbered pages, an even-numbered page has already been printed on the opposite side of the sheet, and then the even-numbered pages after that even-numbered page are printed, and the ρ sheet is placed on the transport loop. It turns out that there is. When this ha page is output to the auxiliary tray 1-15 as a sample print, the even-numbered pages after the even-numbered page that is the back side of the odd-numbered page have already been printed, so the page order of the sheets on the conveyance loop will be disrupted. If the paper is ejected to the staff 11-13 as it is, missing pages or the page order will be disrupted.

To allow sample printing of odd-numbered pages and still maintain the correct page order in that case, the following methods are available: ■ Regarding the even-numbered pages of the sheets to be sample printed, all the sheets on which only the even-numbered pages have already been printed are also placed in the auxiliary tray. Then, the predetermined even-numbered pages and subsequent pages that have already been printed are reprinted on the sheet to be sample printed.

■ With regard to the predetermined even-numbered pages and subsequent pages of the sheets to be sample printed, the sheets on which only the even-numbered pages have already been printed are not sent to the pre-stacker transport path 1-12 or later at the normal timing, but are transported through the transport loop only two more times. rotate around. That is,
In the first cycle, the even-numbered pages are fed to the sheets that are placed in the same position as the sample-printed sheets, and in the second cycle, the odd-numbered pages are After the page is printed, it is branched to the pre-stacker transport path 1-12 at the normal timing.

There are two possibilities.

According to the above-mentioned plan (2), if the page for which sample printing is requested during printing is an odd-numbered page, all the printed sheets of even-numbered pages on the transport loop at that time are ejected to the auxiliary tray 1-15. This not only results in wasted sheets, but also reduces throughput by the time it takes to reprint all the pages that are ejected to the auxiliary tray 1-15.

Also, if you adopt plan ■, there will be no waste of paper (7) (
7) requires complicated control to match the consistency of pages, and also causes a greater reduction in throughput than Plan (2) because it is necessary to rotate the transport loop twice.

As explained above, if sample printing is allowed for odd-numbered pages (second side of a sheet), ■ Page omission or page order disorder.

■ Significant decrease in throughput.

Waste of paper.

Inconveniences may occur if any one of these or a combination thereof is used.

In this embodiment, in step 14-2, sample printing is allowed only for even-numbered pages (the first side of the sheet), thereby preventing the above-mentioned inconvenience from occurring.

Here, the procedure for responding to a sample print request during double-sided printing in this embodiment is summarized as follows (7th, 1st
(See Figure 4).

``After a sample print request is generated, the first even-numbered page (first side of the sheet) is taken as a sample print, and the same page is immediately outputted to the auxiliary tray 1-15 after printing, and the sample print page is used as the next page. The sample print is reprinted at the timing of even-numbered page printing.''Here, the sample print refers to a sheet stacking means (see Figure 1) that is different from the original printed sheet loading means (see stacker 1-13 in Figure 1). Auxiliary trays 1-15 (called "sample trays" in laser beam printers)
The process is to eject the printed sheet to the printer.

The features of the recording device according to the present invention can be summarized as follows.

■ You can easily print samples while double-sided printing is in progress.

■ The integrity of pages loaded into the stacker is not affected.

■ Only one sample is output for each sample request, so many samples are not outputted unnecessarily.

■ Throughput reduction is minimal (the reduction is only the time it takes to print on the sampled paper).

■ The time from requesting a sample to receiving the sample output is short (responsiveness is good).

[Effects] As explained above, according to the present invention, the consistency of the pages of recorded sheets, which are the original output, is maintained correctly, the decrease in throughput is kept to a minimum, and while maintaining good responsiveness, double-sided printing is possible. A sample print function can be realized during recording.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a sheet conveyance system of a duplex printing apparatus which is an embodiment of the present invention, and FIG. 2 shows the conveyance system shown in FIG. 1 and the state of sheets flowing over it. Schematic diagram, Figure 3 is a schematic diagram of an offline printing system to which the present invention is applied, Figures 4 (1) to (3) are diagrams showing the structure of registers etc. shown in Figure 3, Figure 5 is an initialization diagram. Flowchart showing the procedure, Figure 6 is a flowchart showing the page creation procedure, Figure 7 (1) and (2) is a schematic flowchart showing the printing procedure, Figure 8 is a detailed flowchart showing the printing procedure for one page, Figure 8 is a detailed flowchart showing the setting procedure for odd-numbered pages, Figure 1O is a detailed flowchart showing the loading procedure for even-numbered pages, Figure 11 is a detailed flowchart showing the blank print execution procedure, and Figures 12 (1) - (24) and Fig. 13 (1) to (4)
) are schematic diagrams showing the situation during double-sided printing, and FIG. 14 is a detailed flowchart showing the procedure for determining a sample print request and responding to the sample print. 1-1...Paper feeding section, 1-2...Pre-transfer conveyance path, 1-3...Drum, 1-4...Transfer charger. 1-5... Pre-fixing conveyance path, 1-6... Fixing device, 1-7... Pre-fixing conveyance path. 1-8... Branching mechanism before reversal, 1-9... Conveyance path before reversal, 1-10... Reversing mechanism, 1-11... Conveyance path before reversal, 1-12... Before stacker Conveyance path, 1-13...Stacker, 1-14...Stacker front branching mechanism, 1-15...Auxiliary tray, 2-1...Sheet conveyance loop, 2-2-1~ 2-2-5...Sheet being conveyed, 3-1...Magnetic tape (MT), 3-2...Magnetic information converter, 3-3...Central processing unit (CPU) ), 3-4... Page buffer, 3-5... Printing hardware, 3-6... Printing device, 3-7... Management register group, 3-8... Separation register group, 3-8... Print register group, 3-10... Page pointer, 3-11... Page number counter, 3-12... Separate set pointer, 3-13... Separate read pointer, 3 -14...Print pointer, 3-15...Print counter, 3-16...Double-sided spacing register, 3-17...Copy number register, 3-18...Copy number counter, 3-18...Sample print request means, 3-20.
...Sample flag register, 3-7-1...Page presence/absence flag, 3-7-2...Page buffer pointer, 3-8-1
...Separate management pointer, 3-9-1...Print flag (possible/inhibited), 3-8-2.
...Print management pointer, 3-8-3...Part number counter, 3-9-4...Page index (even/odd), 5-1 to 5-
15.6-1~B-12,7-1~? -40°8-1~
8-4. 9-1 to 9-5. 10-1 to 10-4. 11-1 to 11-2. 14-1 to 14-4... control steps. Figure 2 Figure 4 (2) Figure 4 (3) 3-. 4 From Figure 8 7-5 to 7-7 Figure 9/7-26 to Figure 10 To 7-21 To 7-29/7-22 Figure 13 (3) (4) Figure 14 7-7 Than

Claims (1)

[Claims] 1) In a recording device capable of double-sided recording, without affecting the sheet stacking state on the first sheet stacking means,
A recording apparatus characterized by comprising a control means configured to discharge a recorded sheet to a second sheet stacking means during double-sided recording. 2) a first means for writing recorded information into a buffer memory in a predetermined sequential pattern; a second means for separating recorded information on the buffer memory into two types of groups during said writing; 2. The recording apparatus according to claim 1, wherein said control means comprises a third means for reading out the recorded information from the memory in a predetermined order pattern different from that in writing. 3) In response to a request for discharge of a recorded sheet to the second sheet stacking means during double-sided recording, a predetermined page relationship is maintained between the front and back surfaces of the recording sheet and between the sheets. 2. The recording apparatus according to claim 1, further comprising a control means. 4) The control means is configured to minimize a decrease in throughput due to discharge of recorded sheets to the second sheet stacking means during double-sided recording. recording device. (Margin below)