JPH0653422B2 - Double-sided recording page printer - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a double-sided recording page printer that prints on both sides of one sheet.

[Prior art]

In the prior art, there is a so-called double-sided copy in which an image is formed on both sides of one copy paper. in this case,
The copy sheet is sent to the copy processing section, and after being copied on one side thereof, it is turned upside down and sent again to the copy processing section. As one of the copy paper feeding devices for that purpose, a copy paper storage unit for stacking and storing new copy paper which has not been copied yet, and one copy of the copy paper storage unit are fed to the copy processing unit. A first feeding device, and an intermediate tray that stores the copy paper fed to the copy processing unit and having a copy image formed on one surface thereof from one side in a reversed state. , A second feeding device that feeds the copy sheets stored in the intermediate tray from the one side to the copy processing section one by one. In this apparatus, when the copy sheet in the intermediate tray is sent to the copy processing section again, it is switched back here so as to be pulled out in the direction opposite to the direction in which the copy sheet is entered.
For this reason, the upper and lower sides of the paper surface, that is, the top and bottom of the sheet are reversed as compared with when they are sent from the copy sheet storage section to the copy processing section, and it is not possible to obtain a double-sided copy in which the top and bottom sides are aligned. To improve this problem, for example, Japanese Patent Publication No. 60-
In Japanese Patent No. 44656, an intermediate tray in the above-mentioned copy paper feeding device is configured to be substantially rotated by 180 degrees in increments of 180 degrees with the surface of the copy paper stored in this tray as a rotation surface. It is shown.

[Problems to be Solved by the Invention]

In the related art in which the intermediate tray is rotated in a divided manner, the feeding path of the copy paper is complicated, and paper jams are likely to occur. In addition, since a space for accommodating the device for rotating the intermediate tray in a divided manner is required, there is a problem in that miniaturization is hindered. Therefore, an object of the present invention is to realize double-sided recording with a simple configuration in a page printer different from a copying machine.

[Means for Solving the Problems]

The features of the present invention include a recording paper tray on which unprinted recording papers are stacked, a paper feed roller provided on the recording paper tray, and a top recording paper stocked on the recording paper tray. A first feeding device that feeds to the recording unit to record on the surface thereof, and the recording paper fed to the recording unit and recorded on the surface thereof, with the top and bottom and the front and back reversed. A second tray that guides the intermediate tray that stores the sheet and the recording sheet that is stored in the intermediate tray to the first sheet feeder so that the recording sheet is re-fed to the back side for recording. An apparatus, a paper sensor provided in the second feeding device for prohibiting rotation of the paper feed roller and outputting a signal for printing on the back surface of the recording paper, and the recording paper by the output of the paper sensor. When recording on the back side of the Is the address signal coming, there is to that constituted by the address conversion circuit to produce an inverted signal to be converted in reverse order and when recording on the surface of the recording paper.

[Action]

The top and bottom of the recording paper stored in the intermediate tray is turned upside down, but when it is re-fed and recorded on the back surface, it is different from when the address signal is recorded on the front surface by the address conversion circuit. Since the order is reversed, the recording on the back side is the same as the recording on the front side.

【Example】

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of an apparatus equipped with an electrostatic transfer type recording unit, which records data stored in a data buffer on recording paper in accordance with an address signal sent from a central processing unit. The section 1 includes a photosensitive drum 11 and a transfer unit 1.
Includes 2 and. Around the outer periphery of the photosensitive drum 11, a charging device, an electrostatic latent image forming device, and a developing device which are not shown but are known per se, and the recording paper 2 passing between the transfer means 12 and the photosensitive drum 11 in the recording unit 1. And a cleaning device located after the development is transferred to the cleaning device. The unprinted recording papers 2 are stacked in the recording paper tray 3, and the uppermost recording papers are fed one by one by the paper feed roller 4 for recording on the surface thereof.
The recording paper 2 sent out is conveyed by a conveying path 51 and conveying rollers 52.
The sheet is conveyed to the recording unit 1 by the first feeding device 5 including. A paper sensor 6 is provided in front of the recording unit 1,
The leading edge of the recording paper 2 conveyed by the first feeding device 5 is detected. The photosensitive drum 11 is rotated according to this detection signal, and the development on the photosensitive drum 11 is transferred onto the recording paper 2 by the transfer means 12. A fixing unit 7 is provided at a position outside the recording unit 1. Fixing unit 7
Then, the toner image transferred onto the recording paper 2 is fixed by heat fixing or pressure fixing. The recording paper that has left the fixing unit 7 and has been recorded on the surface thereof is guided to the movable conveyance path 8 and is taken up in the intermediate tray 9 with its top and bottom and the front and back reversed. The movable conveyance path 8 is provided with an L-shaped lever 82 by an electromagnet device 81.
The other end 8 of this lever 82 is swung about 2a.
The conveyor plate 83 is supported by the 2b. When the double-sided printing signal is supplied to the electromagnet device 81, the lever 82 is attracted and swings clockwise around the one end portion 82a, the transport plate 83 is at the position shown by the solid line, and the fixing unit 7 is provided.
The recording paper 2 ejected from the sheet is guided toward the intermediate tray 9 which is provided in a downwardly inclined shape. Recording paper 2 accommodated in the intermediate tray 9
Slides on the upper surface of the intermediate tray, and then re-feeds it to the recording unit 1 for recording on the back surface thereof.
It is supplied to the second feeding device 13 which leads to. A paper sensor 14 for detecting passage of the recording paper 2 is provided in the second feeding device 13. The movable conveyance path 8 is provided with a lever 82 when a double-sided printing signal is not input to the electromagnet device 81.
Is at the position shown by the chain line, and the recording paper 2 coming out of the fixing unit 7
The sheet is guided toward the conveying roller 15 by the conveying plate 83 and is discharged to the paper discharge tray 16. FIG. 2 shows an example of the supply means 20 of the signal corresponding to the image character information recorded on the recording paper 2 by the recording unit 1.
Data for pages is stored in the data buffer 21. When the address generation circuit 23 addresses the data buffer 21 in accordance with the address signal sent from the central processing unit 22, a part of the data is sent to the shift register 24. When the inverted signal P from the address conversion circuit 25 is not input to the address generation circuit 23, addressing is performed in the positive address order. That is, the address numbers starting from the top row of one page are sequentially designated to the bottom row. The address conversion circuit 25 is output according to the output from the paper sensor 14.
When the inversion signal P is supplied to the address generation circuit 23 from this, this addressing is performed in the reverse order. That is, 1
Address numbers are specified starting from the address number at the bottom of the page and ending at the top. The data thus sent to the shift register 24 according to the address designation is serially converted here by the input of a signal from the control signal generation circuit 26, and is output to the recording unit 1 as a dot pattern. The inversion signal P is output when printing on the second side (back side) when printing on both sides of one sheet of paper, and the top and bottom of the page, that is, the top and bottom sides of printing are reversed. Is preventing things. When an output is generated on the paper sensor 14 in the second feeding device 13, that is, when the recording paper 2 passes through the second feeding device 13 to be re-fed from the intermediate tray 9, the paper sensor 14 is detected. When the output is generated, the output inhibits the rotation of the paper feed roller 4 so that the unprinted recording paper 2 is not sent out from the recording paper tray 3. The output from the paper sensor 14 is for printing on the back surface of the recording paper 2. With this output, an inversion signal P is generated from the address conversion circuit 25 and supplied to the address generation circuit 23. Further, by this output, the double-sided printing signal given to the electromagnet device 81 is cut off, the carrier plate 83 is set to the position indicated by the chain line in FIG. 1, and the recording paper 2 recorded on the back surface is discharged to the discharge tray 16. When performing double-sided printing, first, when a double-sided printing command is given, the electromagnet device 81 is driven and the lever 82 swings,
The carrier plate 83 is in the state shown by the solid line in FIG. At the same time, the paper feed roller 4 is driven so that the topmost recording sheet 2 stacked on the recording sheet tray 3 with the back side positioned on the upper side is the top side (top) first. It is sent to the feeding device 5 and conveyed to the recording unit 1. When the leading edge of the recording paper 2 passes the paper sensor 6, it is detected and the photosensitive drum 11 is started. At the same time, a signal is supplied from the control signal generation circuit 26 to the shift register 24, and a dot pattern is sent from the shift register to the recording unit 1. Supplied. As shown in the first drawing, the recording paper 2 that has passed through the curved first feeding device 5 and reaches the recording portion 1 has its surface located on the upper surface and faces the photosensitive drum 11. . Therefore, as described above, since the shift register 24 contains the data sent by the address designation in the positive order, when the recording paper 2 passes between the photosensitive drum 11 and the transfer means 12, the upper surface of the recording paper 2 is recorded. Image information from the top row to the bottom row is recorded on the (front side). The recording paper 2 recorded on the front surface is sent to the intermediate tray 9 after being fixed by the fixing unit 7 since the transport plate 83 is at the solid line position. When the trailing edge of the recording paper passes through the fixing unit 7, the recording paper 2 slides down to the left toward the second feeding device 13 which moves down to the left. At this time, the lower side (ground) is first, and the recorded surface is located on the upper surface. The passage of the recording paper is detected by the paper sensor 14 while sliding down from the intermediate tray 9 to the left.
The output of the paper sensor 14 causes the paper feed roller 4 to move as described above.
Since the rotation is prohibited, the unprinted recording paper is not delivered from the recording paper tray 3. In addition, the movable conveyance path 8 is
The position is switched to the position shown by the chain line in FIG. Further, since the output of the paper sensor 14 is a signal for printing the back surface of the recording paper 2, the inverted signal P is supplied from the address conversion circuit 25 to the address generation circuit 23 by this signal. Then, similarly to the above, the recording paper 2 passes through the first feeding device 5, the paper sensor 6, and the photosensitive drum 11 and the transfer means 1.
When passing between the two, the back surface is located on the upper surface and faces the photosensitive drum 11, and the lower side (ground) is passed first. At this time, since the shift register 24 contains the data sent by the address designation in the reverse order by the inversion signal P, the upper surface (back surface) of the recording paper 2 is included.
At this time, the image information from the bottom row to the top row is sequentially recorded, so that the image information is recorded on both front and back surfaces. This recording paper passes through the conveyance roller 15 and is sent out to the paper discharge tray 16, and the double-sided printing is completed without turning the top and bottom sides upside down. A recording unit 10 shown in FIG. 3 is an impact type in which a print head 102 is opposed to a platen 101 and an ink ribbon 103 is interposed therebetween. A dot pattern is generated by the print head 1 by the signal supply means 20 shown in FIG.
02, the print wire (not shown) of the print head 102 shock-contacts the recording paper 2 via the ink ribbon 103, and a predetermined dot pattern is formed on the recording paper 2. In this example, a conveying roller 17 is provided instead of the fixing unit 7 shown in the first figure. In FIG. 3, the parts corresponding to those in FIG. 1 are designated by the same reference numerals as those in FIG.

According to the present invention, in the page printer having the data buffer, since the second feeding device is provided with the paper sensor, it is determined whether the printing is the front side printing or the back side printing, and the back side printing is performed on the recording paper. In this case, the output of this paper sensor prohibits the feeding of unprinted recording paper, the address conversion circuit outputs an inversion signal, and the address signal sent from the central processing unit is transferred to the recording paper by the inversion signal. It is converted in the reverse order of recording on the surface of. Therefore, when it is possible to perform double-sided recording in which the top and bottom are aligned without having to reverse the intermediate tray, the configuration is simplified, the recording paper can be smoothly transported, and the recording paper can be provided at low cost.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a schematic configuration diagram, FIG. 2 is a block diagram of signal supply means,
FIG. 3 is a partial schematic configuration diagram of another embodiment. 1, 10 ... Recording unit, 2 ... Recording paper, 3 ... Recording paper tray, 4 ... Paper feeding roller, 5 ... First feeding device, 9 ... Intermediate tray, 13 ... Second Feeding device, 14 ... Paper sensor, 21 ... Data buffer, 22 ... Central processing unit, 25 ... Address conversion circuit, P ... Inversion signal.

Claims (2)

[Claims] 1. A double-sided recording page printer having a recording unit for recording data recorded in a data buffer on recording paper according to an address signal sent from a central processing unit, wherein unprinted recording paper is in a stacked state. The recording paper tray that is stocked by the recording paper tray, the paper feed roller that is provided in the recording paper tray, and the topmost recording paper that is stocked in the recording paper tray are fed to the recording unit to record on the surface. A first feeding device, an intermediate tray for feeding the recording paper fed to the recording unit and recorded on the surface thereof into the inverted state of the top and bottom, and accommodating it, and is accommodated in the intermediate tray. And a second feeding device that guides the recording paper to the first feeding device so as to re-feed the recording paper to the recording unit for recording on the back surface thereof, and the second feeding device. , The above-mentioned paper feed roller A paper sensor that prohibits rotation and outputs a signal for printing on the back surface of the recording paper, and when recording on the back surface of the recording paper by the output of the paper sensor, the paper sensor sent from the central processing unit A double-sided recording page printer, comprising: an address conversion circuit for generating an inversion signal for converting an address signal in the reverse order of the case of recording on the surface of the recording paper. 2. The double sided structure according to claim 1, wherein the intermediate tray is provided in a downwardly inclined shape, and the recording paper is slid and supplied to the second feeding device. Record page printer.