JPH0342543B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a double-sided recording device that records images on both sides of a recording material.

2. Description of the Related Art Conventionally, an apparatus has been proposed that records images such as characters on a recording material by turning a laser on and off in accordance with data output from a host computer or the like.

In such a device, recording can only be performed in the order of input image data, so if you try to record images on both sides of the recording material, depending on the feeding direction of the recording material or the direction of the arrow, the surface of the recording material may be There is a problem in that the direction and order of the recorded images are different on the back side.

The present invention has been made in view of the above points, and an object thereof is to provide a double-sided recording device that can properly record the direction and order of images on the front and back sides of a recording material. be.

That is, the present invention provides a data output means for outputting recording data, a recording means for recording an image on a first side and a second side of a recording material according to the recording data output from the data output means, and a recording material by the recording means. A double-sided recording apparatus is provided, comprising: a control means for controlling the data output means so as to vertically convert recorded data and output it to the recording means during recording on the second side of the double-sided recording apparatus.

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

FIG. 1 is a sectional view of an embodiment of a double-sided recording device according to the present invention, and 1 and 2 are recording units that record images on the front and back sides of a sheet, respectively, using a laser beam printer (hereinafter referred to as LBP). It is configured. LBPs 1 and 2 have similar configurations.
Reference numeral 3 denotes a reversing unit for reversing sheets, and 4 a paper feed cassette, which is attached to the first laser printer and placed in the pedestal 21 without being attached to the second laser printer. 5 is a paper ejection tray, which is not attached to the first LBP 1, but is removed and stored in the pedestal section, and is not attached to the first LBP 1.
2 is installed. 6 is a cradle for receiving the paper feed cassette 4, and 7 is for receiving one sheet from the paper feed cassette 4.
A pick up roller 8 takes out the sheets one by one, and a registration roller 8 sends the taken out sheets to the transfer section at a predetermined timing. 9 is a photosensitive drum, 1
0 is a charger that uniformly charges the surface of the photosensitive drum, 1
1 is a semiconductor laser, 12 is a scanner, 13 is a laser beam, 14 is a folding mirror, 15 is a developer,
16 is a transfer charger, 17 is a cleaner, and a scanner 12 scans the laser beam 13 of the semiconductor laser 11, which flashes in response to image information, in the longitudinal direction of the photosensitive drum 9 to form an electrostatic latent image on the photosensitive drum 9. is formed, and a toner image is obtained by a developing device 15.
18 is a conveyor that conveys the sheet with the toner image transferred thereto using a suction mechanism and a belt;
19 is a fixing device that heats the toner image on the sheet;
20 is a paper ejection roller. 21 is a pedestal on which the LBP is placed, and 22 casters are attached to it, allowing it to move on the floor surface 23.

Next, the configuration of the reversing device 3 will be explained. 24
is the first connection part with the first LBP 1, and is attached to the pedestal 25 that remains after removing the paper discharge tray 5. 26 is the second connection part with LBP2,
It is attached to the holder 6 where the paper feed cassette 4 was removed. A conveyor 27 conveys the sheet with a belt, and a conveyance roller 28 contacts the conveyance belt of the conveyor 27 to send out the sheet. Reference numeral 29 denotes a sheet separating plate, which is used to sort odd-numbered sheets, which are sequentially conveyed by the conveyor 27, upward and even-numbered sheets downward. Reference numeral 30 denotes a separation shaft that is the center of swing of the sheet separation plate. 31 is a reversing roller, 32 is an input roller, and 33 is an output roller, which rotate in the direction of the arrow in contact with each other, and there are two sets in the upper stage and the lower stage. 34 is an upper reversing guide, and 35 is a lower reversing guide, in which the sheet is switched. 36 is an up roller that rotates in a direction to lift up the sheet fed into the reversing guide 34 or 35; 37 is a down roller that rotates in a direction that sends the sheet downward; 38, 39;
The pressure roller moves in seesaw motion to feed the sheet against the rollers that are in contact with each other. 40 to 45 are guide plates for guiding the sheet. Reference numeral 46 denotes a conveyor for conveying sheets with a belt, and 47 a refeed plate, which is supported by a rotation shaft 48 and urged upward by a paper feed spring 49.
50 to 53 are sheet sensors that detect the leading edge or trailing edge of the sheet. Reference numeral 50 denotes a sheet sensor for activating the separation plate 29 a predetermined time after the leading edge of the sheet is detected. Reference numeral 51 denotes an upper sheet sensor for detecting the trailing edge of the sheet and at the same time moving the pressure rollers 38 and 39 in seesaw motion to reverse the feeding direction of the sheet. Similarly, 52 is a lower sheet sensor for detecting the trailing edge of the sheet and at the same time moving the pressure rollers 38 and 39 in seesaw motion to reverse the sheet feeding direction. Reference numeral 53 denotes a sheet sensor that detects the leading edge of the sheet being conveyed by the conveyor 46 while being attracted to the belt, and at the same time drives the pickup roller 7 of the second LBP 2 to re-feed the sheet.

54 to 58 are cooling fans. first
A sheet printed on one side (front side) with LBP 1 has residual heat due to heat fixing, and is cooled by cooling fans 54 to 58 to prevent curling of the sheet and toner offset to the apparatus. Additionally, the exterior of the reversing device is provided with louvers at key points to take in cold air. Note that the upper and lower reversing guides 34 and 35 are provided with ventilation holes (not shown) such as punched metal holes for sheet cooling. 5
Reference numeral 9 indicates a moving caster of the reversing device, which floats above the floor surface 23 in the connected state.

FIG. 2 is a front view of the reversing device 3 shown in FIG.
8 and 39, the crimping mechanism and the crimping release mechanism are shown. Reference numeral 60 denotes a front plate of the reversing device 3, which is supported by a bearing (not shown) so as to be able to swing with respect to the separation shaft 30. A separation arm 61 is fixed to the separation shaft 30.

62 is an electromagnetic solenoid, 63 is a link, 64 is a tension spring, and 65 and 66 are stoppers. When the electromagnetic solenoid 62 is not energized, the separation plate 29 is directed downward under the action of the tension spring 64 to send the sheet conveyed from the direction A of the arrow in the direction of the arrow B, that is, to the upper reversing guide 34 . On the other hand, when the electromagnetic solenoid 62 is energized, the separating plate 29 faces upward as shown by the broken line in FIG.
In other words, it is fed into the lower reversing guide 35. 67
A pressure bonding arm rotatably supports the pressure bonding rollers 38 and 39 by bearings, and performs seesaw movement around a swinging shaft 68 to switch the sheet feeding direction.
69 is a tension spring, 70 is a link, 71 and 72 are upper and lower electromagnetic solenoids, and 73 is a stopper. Normally, the up roller 36 and the pressure roller 38 are in contact with each other in the upper inversion section, and the down roller 37 and the pressure roller 39 are in contact with each other in the lower inversion section. When the excitation solenoids 71 and 72 are excited, the electromagnetic arm 67 seesaws.

FIG. 3 is a rear view of the reversing device 3, showing a drive mechanism for rotationally driving the conveyors 27, 46, the upper and lower reversing rollers 31, and the up/down rollers 36, 37. Reference numeral 74 denotes a rear side plate of the reversing device 3, which supports the various rollers mentioned above together with the front side plate 60 by bearings (not shown). 75 is a drive motor, 76 and 77 are timing belts, 78 is a drive pulley, 79 to 84 are driven pulleys, and 85 is an idler pulley. 86 and 87 are driven gears,
The driven pulleys 80, 81, and 84 are engaged with a gear (not shown) on the back side. In addition, driven pulleys 79 to 8
4 and driven gears 86, 87 are connected to the conveyor 27,
46 and the rotation shafts of the upper and lower reversing rollers 31 and up/down rollers 36 and 37, respectively.
The timing belts 76, 7 are driven by the drive motor 75.
7 and driven gears 86 and 87 to rotate in a predetermined direction.

The printing operation during double-sided recording in the above configuration will be described below. First, from the paper feed cassette 4 of the first LBP 1, the first
Feed the first sheet. Then, in order to synchronize with the first page toner image formed on the photosensitive drum 9, the registration roller 8 feeds the toner image to the transfer section at a predetermined timing, and the photosensitive drum 9 is fed by the transfer charger 16.
Transfer the upper toner image onto the sheet. Then, the sheet is fed by the conveyor 18 to a heat fixing device 19, and the toner image of the first page is fixed on the surface of the sheet.
Then, the sheet is discharged from the LBP 1 to the reversing device 3 by the sheet discharge roller 20. Further, a sheet is fed from the paper feed cassette 4 at a predetermined timing, and odd-numbered pages such as the third page, the fifth page, and so on are recorded on the surface of the sheet as described above.

Next, in the reversing device 3, the drive motor 75 is started at the same time as paper feeding is started in the first LBP1. Then, the sheets discharged from the LBP 1 are suctioned and conveyed in order by a conveyor 27, and are sent to a conveyance roller 28 while the image surface is cooled by a cooling fan 54. At this time, the separation plate 29 is in a state as shown by the solid line in FIG. Therefore, the sheet is separator plate 2
9 and along the guide plates 40 and 42 to the input roller 32, and further upward along the reversing guide 34, and lifted by the up roller 36. The trailing edge of the sheet passes through the input roller 32, and the sheet is completely accommodated in the upper reversing guide 34.

At this time, all residual heat from heat fixing is removed from the sheet within the reversing guide 34 by cooling fans 55 and 56, and the sheet is also lightly pressed against the left wall surface of the reversing guide by wind pressure. Then, at the same time as the sheet sensor 51 detects the rear end of the sheet, the upper electromagnetic solenoid 71 is energized to cause the crimp arm 67 to seesaw. That is, the contact between the up roller 36 and the pressure roller 38 is released, and the down roller 37 and the pressure roller 39 are brought into contact with each other, and the rear end of the sheet is sent to the output roller 32 below. The thus reversed sheet is conveyed along guide plates 43 and 44 onto conveyor 4.
6, the paper is sucked, conveyed by the belt, and placed on the paper refeed plate 47.

At this time, when the sheet sensor 53 detects the leading edge of the sheet, the printing operation of the second LBP 2 is started. In the second LBP 2, the backup roller 7 rotates, feeds the reversed first sheet, prints the toner image of the second page on the back side of the first sheet, and discharges the paper. Discharge to tray 5.

By the way, the second sheet following the first sheet is
In the reversing device 3, the sheet sensor 50 detects the leading edge of the second sheet, and after a predetermined time, the separating electromagnetic solenoid 62 is energized, and the separating plate 29 is accommodated in the lower reversing guide 35 facing upward. At the same time when it is detected that the rear end of the sheet has passed the sheet sensor 52, the excitation solenoid 72 is energized to bring the up roller 36 and the pressure roller 38 into contact, and in cooperation with the wind pressure of the cooling fans 57 and 58, the rear end of the sheet is The end is sent to the output roller 33 and the second sheet is reversed.

As described above, the apparatus is configured such that the odd-numbered sheets from the start of printing are reversed by the upper reversing mechanism, and the even-numbered sheets are reversed by the lower reversing mechanism.

Next, an embodiment of the image recording process in the double-sided recording apparatus according to the present invention will be described with reference to FIGS. 4 and 5.

FIG. 4 shows an example in which double-sided recording is performed using exactly the same image forming method on the first LBP1 and the second LBP2. When scanning the surface of the photosensitive drum 9 with the laser beam 13 emitted from the laser 11 using the scanner 12 to form an electrostatic latent image, the top and bottom of the image are adjusted with respect to the scanning direction D (same as the longitudinal direction of the photosensitive drum 9). The image is recorded on the screen of the sheet with the directions aligned, that is, the direction of travel of the sheet and the top and bottom of the image are perpendicular. Therefore, if the character patterns ABC and DEF are printed on one side as shown in Figure 4, the direction of travel of the sheet and the arrangement of the characters match, so the first
Even if the switchback is used to flip between LBP1 and the second LBP2, the top and bottom of the characters on both sides will not be reversed.

FIG. 5 is a block diagram showing a control unit 30 for performing vertical and horizontal conversion of image information as described above and recording on both sides of a sheet using LBPs 1 and 2. This control section 30 is provided in the reversing device 3.

Memories 90 and 91 are capable of storing image information for one page. 92 is a vertical/horizontal conversion control unit that performs vertical/horizontal conversion of the image information stored in the page memory 90 or 91; 93 is a memory for storing the image information for the front surface that has been vertically/horizontally converted by the vertical/horizontal conversion control unit 92; 94 is a vertical/horizontal converter; The memories 93 and 94 are memories for storing image information for the back side that has been vertically and horizontally converted by the conversion control unit 92, and are capable of storing additional information for one page. 95 is a switch for selecting page memories 90 and 91 for storing image information; 96 is a switch for selecting page memories 90 and 91 for storing image information;
97 is a switch for selecting the front side image memory 93 or the back side image memory 94 for storing the vertically and horizontally converted image information, and 98 is the address of the page memory 90, 91. is the address bus to select.

When the image information sent from the CPU, MT, etc. is image information that should be recorded on the front surface of the sheet, the switch 95 is switched to the position indicated by the broken line, and one page of the image information sent is stored in the page memory 90. Store.
Next, the switches 96 and 97 are switched to the solid line positions to read image information from the page memory 90. In this case, the address bus 98 is controlled by the vertical/horizontal conversion control unit 92 so that data written in the page memory 90 in the row direction is read out in the column direction. The image information read out in this way and converted vertically and horizontally is stored in the front side image memory 93. Based on this image information
An image is recorded on the surface of the sheet by LBP1.

Further, when the image information is read from the page memory 90, the switch 95 is switched to the solid line position and the image information for the back side is stored in the page memory 91. When the recording on the front side is completed, the image information is read out from the page memory 91 as described above, converted vertically and horizontally, and stored in the image memory 94 for the back side. Based on this image information, an image is recorded on the back side of the sheet.

Next, another embodiment of the image recording process in the double-sided recording apparatus according to the present invention will be described with reference to FIGS. 6 and 7.

FIG. 6 shows an example of double-sided recording using different image forming methods for the first LBP1 and the second LBP.
In the first LBP1, an image is laser recorded from top to bottom in the rotational direction E of the photosensitive drum 9, and in the second LBP2, the image is recorded by laser in the opposite direction from the bottom to the top. That is, the image is printed so that the top and bottom of the image are reversed at the switchback type reversal with respect to the direction in which the sheet travels.

Therefore, as shown in Figure 5, if the character patterns ABC and DEF are printed on one side, the top and bottom of the letters relative to the direction of sheet travel are reversed before and after the switchback type reversal, so the top and bottom of the letters on both sides are reversed. There's nothing to do.

FIG. 7 is a block diagram showing a control section 40 for performing vertical conversion on only the back side information of the image information and recording images on both sides of the sheet using LBPs 1 and 2 as described above. This control section 40 is provided in the reversing device 3.

In FIG. 7, components with the same numbers as in FIG. 5 are the same components; 99 is an orientation conversion control unit for converting the orientation of image information;
This is an address bus for selecting one address.

The front image information sent from the CPU, MT, etc. is stored in the front image memory 93 from the switch 95. Based on this image information, the LBP 1 records an image on the surface of the sheet. Further, the image information for the back side is stored in the page memory 91 from the switch 95. Then, address control is performed by the vertical conversion control unit 99 so that the data written in the page memory 91 in the row direction is read out from the last row in the opposite direction to the written row direction. The image information that has been vertically converted in this manner is stored in the back side image memory 94, and based on this image information, image recording is performed on the back side of the sheet by the LBP 2.

The sheets printed on the paper output tray 5 using the above-mentioned double-sided recording method are taken out,
It can be filed and bound on the left or right side.

However, when binding the top side of a sheet into a file or book, such as folding output paper from a line printer and binding the top side in a bag,
As shown in the image recording process shown in FIG. 8 and the broken lines in the block diagram of FIG. Information for the surface, second LBP
Send the information for the back side to 2 and print.

Therefore, it is possible to predetermine the binding direction of printed sheets and select either a double-sided recording method or a single-sided recording method to print on both sides of the sheet.

In this embodiment, a laser beam printer using a semiconductor laser is used as the recording device, but the present invention is not limited to this. For example, an electrophotographic printer using an LED array, a printer using a multi-stylus, etc. may be used.

Further, a control section for changing the direction of image information may be provided in the reversing device 3, or may be provided in each printer.

As explained above, double-sided recording can be easily and inexpensively achieved by using two small, low-cost single-sided recording devices and a switchback-type sheet reversing device connected between them. .

Further, since the reversing device has two sets of upper and lower reversing mechanisms, which are used alternately, double-sided recording can be performed at the maximum printing speed of the recording apparatus without reducing throughput.

Furthermore, the structure is such that the sheet is cooled within the reversing device, which prevents the sheet from curling and reduces jams during reversal and refeeding, and also removes the heat of fixing the toner image to ensure that it is completely fused to the sheet. The toner offset to the device can be reduced since the toner is then inverted and reprinted.

Furthermore, by using a printer in which the paper feed section and the paper discharge section are on opposite sides of each other, the sheet is conveyed almost horizontally, and a toner image is printed on the top surface of the sheet, the first printer prints the sheet. The front side of the sheet can be printed first, switched back and reversed, and then the second printer prints the back side of the sheet and outputs it to the output tray, which simplifies sheet conveyance, reduces jams, and outputs the sheet continuously. Not only is it possible to do this, but it also has the effect that the pages are stacked one after another on the ejection tray with the front side of the first sheet facing the bottom side, so that the pages are aligned.

Further, the reversing device is provided with a vertical/horizontal or vertical/vertical conversion circuit for changing the direction of image information, and can output double-sided prints suitable for sheet filing methods and bookbinding methods.

Furthermore, when double-sided printing is not required, the printer can be separated from the reversing device and used as an independent small terminal device.

Furthermore, double-sided recording can be performed with a simple configuration without reducing throughput.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a double-sided recording device according to the present invention, FIG. 2 is a front view of a reversing device, FIG. 3 is a rear view of the reversing device, and FIGS. 4 and 6 are a double-sided recording apparatus according to the present invention. FIG. 5 and FIG. 7 are block diagrams showing a control unit that converts image information, and FIG. 8 is a schematic perspective view showing the image forming process in a single-sided recording method. 1 is a first LBP, 2 is a second LBP, 3 is a reversing device, 4 is a paper feed cassette, 5 is a paper ejection tray, 9 is a photosensitive drum, 29 is a separating plate, 31 is a reversing roller,
34 is an upper reversing guide, 35 is a lower reversing guide,
36 is an up roller, 37 is a down roller, 3
8, 39 are pressure rollers, 47 is a re-feeding plate, 50-
53 is a seat sensor, 54 to 58 are cooling fans,
61, 71, 72 are electromagnetic solenoids, 75 is a drive motor, 76, 77 are timing belts, 90 is an image vertical/horizontal conversion circuit, 95 is an image vertical conversion circuit,
A, B, and C are the sheet traveling directions, D is the laser scanning direction, and E is the rotation direction of the photosensitive drum.

Claims (1)

[Scope of Claims] 1. Data output means for outputting recording data; Recording means for recording an image on a first side and a second side of a recording material according to the recording data output from the data output means; By the recording means. A double-sided recording apparatus comprising: a control means for controlling the data output means so as to vertically convert recording data and output it to the recording means when recording on a second side of a recording material.