JPS63303745A - Multicolor printer - Google Patents

Abstract

PURPOSE:To enable the control of recording resumption resulting from the generation of jam to be simply performed by controlling in such a way that a timing generation means for subscan initiation may cause a recording medium to start the subscan, when the completion of forming a latent image is detected. CONSTITUTION:Paper S accumulated on the top of a paper feed cassette 21 is fed to a transport path 24, but the tip of the paper S is detected by the first sensor S1 and the second sensor S2 while the paper is guided to the position of a transfer device 10. Then when the completion of forming all images of different colors is detected by a means to detect the completion of forming d plurality of images of different colors on a single page of material to be recorded S, a subscan direction synchronizing signal for a next page of material to be recorded is output. That is, where the tip of the paper is detected by the first sensor S1, a signal VSREQ1 is output, and at the same time, the transport of the paper is once suspended so that the subscan and transport by a photosensitive drum 1 may be synchronized. Then the transport is again started by the input of a signal VSYNC1, and the paper is fed by the first image signal VDOt. When the tip of the paper is detected by the second sensor S2, a signal VSREQ2 is sent to a controller 40, and the second image signal VDO2 is supplied with the entry of a signal VBYNC2.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a multicolor printer, and in particular, a latent image is sequentially formed on one recording medium by a plurality of light sources, and a latent image is formed on the developed upper recording material. The present invention relates to a multicolor printer in which transfer is performed.

(Prior Art) As a conventional multicolor electrophotographic printer of this type, there is a recording device that forms a two-color image using a laser beam.In such a recording device, charging, first exposure, first development,
The second exposure and second development steps are performed on a rotating photosensitive drum, and FIG. 7 shows an example of such a conventional multicolor laser beam printer.

Here, 1 is a photosensitive drum rotating in the direction of the arrow, 2 is a first semiconductor laser, 3 is a second semiconductor laser, and 4
is a rotating polygon mirror that reflects the laser beams from these lasers 2 and 3, and 5 is an imaging lens. Further, 6 and 7 are a first charger and a second charger that charge the photosensitive drum 1, and the photosensitive drum 1 charged by the first charger 6 is rasterized by a laser beam modulated by the first recording signal. The scanning line is exposed to light, thereby forming a first electrostatic latent image. A first developing device 8 develops the first electrostatic latent image using a two-component magnetic brush method using red toner.

The photosensitive drum that has completed the development of the first electrostatic latent image in the first developing device is charged again in the second charging device 7, and is exposed to raster scanning lines by the laser beam from the second semiconductor laser 3, thereby causing the first electrostatic latent image to be developed. 2 electrostatic latent images are formed. Reference numeral 9 denotes a second developing device that develops the second electrostatic latent image using black toner using a one-component magnetic brush method. The image is transferred onto the recording material S by the transfer charger 10.

11 is a static eliminator for removing residual charges on the photosensitive drum 1;
2 is a cleaner for removing residual toner on the photosensitive drum 1;
Reference numeral 13 denotes a static elimination lamp for removing the electric charge remaining on the photosensitive drum 1 after the toner has been removed.

FIG. 8 shows details of the exposure section in the above-mentioned multicolor laser beam printer. Here, 14 is a motor that rotates the side-turning polygon mirror 4 at a constant speed, and 15 is a folding mirror that reflects the laser beam from the first semiconductor 2 to form a raster scanning line Ll on the photosensitive drum 1. Bl is a reflection mirror 16
Detects the laser beam reflected by the raster scanning line L
B2 is a beam detector for detecting the timing to start writing the image signal in the raster scanning line L2, and B2 is a beam detector for detecting the laser beam reflected by the reflection mirror 17 and detecting the timing to start writing the image signal in the raster scanning line L2. be.

In the exposure section configured in this way, the first semiconductor laser 2
When the first picture monk number VIIOI is input to , the signal v
11, the raster scanning line L1 is created by scanning the laser beam with the laser beam modulated on and off by
Similarly, raster scanning lines L2 are respectively formed on the photosensitive drum 1 by scanning of the laser beam modulated by the second image VDO2 manually applied to the second semiconductor laser 3.

FIG. 9 shows an interface between the above-described multicolor (two-color) laser beam printer and a controller to which it is connected, where LBP is the laser beam printer and CNT is the controller. That is, laser beam printer L
BDI is sent from the OP to the controller CNT as a synchronization signal in the main scanning direction for exposure by the first semiconductor laser 2 (hereinafter referred to as "first exposure"), and also as a synchronization signal for exposure by the second semiconductor laser 3 (hereinafter referred to as "second exposure"). BD2 is output as a synchronization signal for the main scanning direction (referred to as exposure). These synchronization signals BD1. BD2 is the same signal obtained from beam detectors B1 and B2 shown in FIG. In addition, VSREQI and VSRE are used as synchronization request signals in the sub-scanning direction by the first and second exposures, respectively.
Q2 is output.

On the other hand, from the controller CNT to the laser beam printer L
For BP, VSYNCI is used as a synchronization signal in the sub-scanning direction for the first exposure, VSYNC2 is used as a synchronization signal in the sub-scanning direction for the second exposure, and VSYNC2 is used as a synchronization signal in the sub-scanning direction for the second exposure. VDDI and VDO2 are output as an image signal corresponding to the first exposure and an image signal corresponding to the second exposure, respectively.

FIG. 10 shows an example of the output timing of the individual signals described above. First, at (^), the synchronization request signal VSREQI in the sub-scanning direction for the first exposure is output from the printer LBP side. Controller C
From the NT, the sub-scanning synchronization signal VSYNCI corresponding to the signal VSREQI is sent to the printer LBP as shown in (B), and at the same time, it is sent to the synchronization signal BDI (C) for the first main scanning direction output from the printer LBP. The first image signal VDOI is synchronously outputted as shown in (D).

Therefore, if the time taken for the photosensitive drum 1 to rotate from the position of the rask scanning line Ll to the position of the rask scanning line L2 shown in FIG. After time TZ has elapsed since the printer LB was sent and received, as shown in (E).
Synchronization request signal VSREQ2 from P to the second sub-scanning direction
is output, and then, within a delay time of 61, the second sub-scanning synchronizing signal VSYNC2 is sent from the computer CNT side as shown in (F), and at the same time the second image signal VDO2 is sent as (H). Supplied as shown in .

Note that here, the delay time amount ΔT between the sub-scanning synchronization request signal VSREQ2 and the sub-scanning synchronization signal VSYNC2 is the first
In order to reduce the image deviation between the image and the second image, the pulse interval To of the second main scanning direction synchronization signal BD2 (shown in (G)) is kept below.

In this way, when image formation for one page on page 0 is completed using the first image No. 42 VDOI as shown in (D),
In order to increase the number of pages recorded per time, the first sub-scanning direction synchronization request signal VSREQI for the next page, that is, page (n+1), is immediately output as shown by (^), and in the same manner, (n+ 1) Similar signals are sent and received to and from the page.

(Problems to be Solved by the Invention) However, in the conventional control system using a multicolor laser beam printer as described above, the first stroke of the nth page
Immediately after the image formation by DOI is completed, the first stroke of the monk number on the (n+1) page is output, and the image formation by the second stroke of the monk number VDO2 of the nth page is as shown in Fig. 1O. There is a possibility that the page is not completed, and this duplication of image data between the page and the next page complicates control in the printer LBP.

For example, if a failure occurs during transportation, which would normally be treated as a jam, on a recording material that has already been transferred, in such a case, the data from the controller to the recording material will be Retransmission information becomes complicated. That is, depending on the timing of the jam occurrence, the retransmission page of the first image information and the retransmission page of the second image information may be different, and in this case, the retransmission page of the first image information and the retransmission page of the second image Both information and the resent page must be sent from the printer to the controller.
Not only page manipulation of the recording material on the printer side, but also control of retransmission of the information on the controller side becomes extremely complicated.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to easily and easily perform printer control using a controller, particularly image formation control and control for restarting recording when a jam occurs in the printer. The objective is to provide a multi-color printer that is possible.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a method for performing main scanning on a recording medium at predetermined exposure positions sequentially using a plurality of light sources, and sub-scanning the recording medium. A latent image for each color is sequentially formed, and a multicolor image is developed from each latent image.The recording material is conveyed in synchronization with the sub-scanning, and a multicolor image is formed on the recording material. In a multicolor printer capable of obtaining transfer, there is a means for detecting the formation of individual latent images, a means for generating the start timing of sub-scanning of the recording medium, and a means for forming the individual latent images by the detection means. The present invention is characterized by comprising means for controlling the recording medium to start sub-scanning by a sub-scanning start timing generating means when it is detected that the sub-scanning has ended.

(Function) According to the present invention, the completion of image formation for all colors is detected by the means for detecting the completion of formation of a plurality of images of individual colors on one page of recording material. Since it is possible to output a sub-scanning direction synchronization signal for the next page of recording material when a jam occurs, it is possible to output a sub-scanning direction synchronization signal for the next page of recording material, which eliminates the conventional complicated operations for image formation control, especially for controlling recording restart when a jam occurs. Steps are no longer required.

〔Example〕

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

FIG. 1 shows the relative positions of the photosensitive drum and recording material conveying means according to the present invention. Here, 21 is a paper feed cassette in which a recording material (hereinafter simply referred to as paper) S is stored, 22 is a paper feed roller, 23^ and 23B are conveyance rollers, and the conveyance rollers 23^ and 23B and the transfer device A first sensor S1 and a second sensor S2, which detect the presence or absence of paper S as a recording material, are connected to the transport path 24.
It is located along the In this example, each l from the first sensor Sl and the second sensor S2 to the transfer device lO,
and °C2, the arc length I along the exposure drum 1 from the transfer device IO to the first exposure position 8 according to the raster scanning line Ll.
11 and the second by raster scanning line L2 from transfer device lO.
They are made to match the arc length 112 up to the exposure position LB.

Therefore, in the printer configured as described above, a clutch (not shown) is turned on and off by a signal from the control section, thereby controlling the paper feed roller 22 and the conveyance roller 23^.
, 23B are driven at a predetermined timing, and the sheets S accumulated in the uppermost layer of the sheet feed cassette 21 are fed to the transport path 24, but the sheets S1 are The tip is detected by the first sensor Sl and the second sensor S2.

Next, the configuration of the control circuit of the multicolor laser beam printer of the present invention will be explained with reference to FIG. Here, 30 is the laser beam printer LBP, 40 is a controller, and the LBP 30 uses its own control unit 31 to perform controls directly related to the printer, such as on/off control of the paper feed roller 22, etc., and monitoring of sensors Sl and S2. Perform the action. 32 is a clutch for the paper feed roller 22;
3 is a clutch for the transport rollers 23^ and 23B, and 3
4 and 35 are a drive unit for the first semiconductor laser and a drive unit for the second semiconductor laser, respectively. By sending various signals from the control section 31 to these drive units 34 and 35, the respective lasers 2 and 3 emit light. For example, a forced margin can be formed on the paper S.

Further, PENB is a signal (print enable signal) that informs the controller 40 that paper can be fed from the control unit 31 of the printer 30, and when this signal PENB is input manually, the controller 40 sends the printer
A paper feed command signal (PRINT) is sent to PR
Paper feeding is started by the INT signal. That is, in the printer 30, when the signal PENB is true, print enable is permitted, and the signal PR from the controller 40 is
When printing is permitted by INT, the paper feeding clutch 32 is turned on to start feeding paper.

36 and 37 are PIN photodiodes (hereinafter referred to as photodiodes) for generating the first main scanning direction synchronization signal BDI and the second main scanning direction synchronization signal BD2, respectively, and are connected to the beam detector shown in FIG. This corresponds to Bl and B2. 38 is a beam detector control circuit, and each signal obtained from the photodiodes 36 and 37 is waveform-shaped by the control circuit 38 and supplied to the controller 40 as main scanning direction synchronization signals BDI and BD2. At this time, the control circuit 3
8, the respective main scanning direction synchronization signals BDI and BD.
2, and if the pulse interval is unstable or pulses are not generated accurately, that information is transmitted to the control unit 31, and appropriate measures are taken via the control unit 31. can be done.

Next, the control operation according to the present invention will be explained with reference to FIG.

First, in step 5101, the presence or absence of paper at the first sensor S1 is determined, and if it is determined that there is no paper, the next step 5 is performed.
At 102, the presence or absence of paper at the second sensor S2 is similarly determined. Thus, if both the first sensor Sl and the second sensor S2 determine that there is no paper, step 51 is performed.
The process proceeds to step 03, where the print enable signal PENB is sent to the controller 40 to notify it that paper can be fed, and in the next step 5104, the print enable signal PRINT from the controller 40 is waited for to become true. . Thus, in step 5104 the signal PRIN
If T becomes true, the process proceeds to step 5105, the enable signal PENB is set to false, and sheet feeding is started in step 5106.

Next, in step 5107, the IT sensor S1 waits for the leading edge of the paper to be detected, and if the leading edge of the paper is detected here, the process proceeds to step 5108, where the printer 30 issues a first sub-scanning direction synchronization request. At the same time as outputting the signal VSREQI to the controller 40, the controller 316) supplies an "off" signal to the clutches 32 and 33 to stop the paper feed roller 22 and the transport rollers 23A and 23B in order to temporarily stop transporting the paper. .

Then, in the next step 3109, wait for the first sub-scanning direction synchronization signal VSYNCI to be input from the controller 40, and once the synchronization signal VSYNCI has been input, the clutches 32 and 33 are turned on again and the paper is transport begins again. Thus, in step 5110, the second
The process waits until the leading edge of the paper is detected by the sensor S2, and if the leading edge is detected, the process proceeds to step 5ill and the second sub-scanning synchronization request signal VSREQ2 is output.

Fig. 4 shows the timing of various signals generated in the above-mentioned control operation by (^) to (L).
As is clear from this figure, the enable signal PENB is output when it is confirmed that the signals from the first sensor Sl and the second sensor S2 are at the "L" level, and thereby the controller 40 side A paper feed signal PRINT for permitting paper feeding is output from the printer to start paper feeding, and then, when the leading edge of the paper is detected by the first sensor Sl, a signal VSREQI is output and at this point, In order to synchronize the sub-scanning and the conveyance by the photosensitive drum 1, the conveyance is temporarily stopped, and conveyance is started again by the manual input of the signal VSYNCI, and at the same time, the first imaging signal VD
OI is fed. In this way, when the leading edge of the paper is detected by the second sensor S2, the signal VSREQ2 is sent to the controller 40, and the second imaging signal VOA2 is supplied together with the human power of the signal VSYNC2. As long as the signals from the first sensor 51 and the second sensor S2 are both at the "off" level, that is, there is no paper in the first and second sensors, even if the image is formed at the above timing, the second sensor The image information is the first page on the next page.
There is no duplication of image information.

FIG. 5 shows the procedure of different control operations according to the present invention. That is, in the control operation shown in FIG.
The enable signal PENB is output when both sensors are at "L" level, but the point is that if the second imaging signal VDO2 is controlled so as not to overlap with the first imaging signal VDOI of the next page. In this example, the enable signal PENB is output when the level of the first sensor is "L". Figure 6 below shows the timing of each signal (^)
The flow will be described with reference to (L).

First, in step 5201, it is determined whether the detection signal from the first sensor Sl is at the "L" level, and if it is determined to be at the "S" level, the second image signal VDO2 is output even if Proceeding to step 5202, the printer 30 outputs an enable signal PENB to the controller 40 indicating that the next page can be fed. Thus, in step 5203, the paper feed permission signal PRINT is waited for, and the signal PRI is input.
If the NT is operated manually, the enable signal PEND is made true in step 5204, and the process proceeds to the next step 5205, where the clutches 32 and 33 are turned on and sheet feeding is started.

If the leading edge of the paper is detected by the first sensor S1 in step 5206, the conveyance is temporarily stopped in order to synchronize the sub-scanning and conveyance in step 5207, and the first sub-scanning direction synchronization request signal VSREQI is sent in step 5208.
is output from the printer 30 to the controller 40. The subsequent operations from step 5209 to step 5213 are similar to steps 5109 to 5211 in FIG. 3, and their explanation will be omitted.

In the above embodiment, the first sensor Sl and the second sensor S2 are arranged on the conveyance path 24 in accordance with the arc length from the first exposure position LA and the second exposure position LB on the photosensitive drum 1 to the transfer device IO, respectively. Although it is placed at the top, it is not necessarily the first
It is not necessary to provide the sensor Sl and the second sensor, and the point is that it is sufficient if the control unit can recognize that the paper has reached the respective corresponding positions on the conveyance path.

For example, the first and second main scanning direction synchronization signals 8D1 and BO2 are counted at the same time as the sheet feeding operation is started, or a rotary encoder is connected to the photosensitive drum 1, and the pulse train generated from the encoder is counted. It is also possible to provide a software timer in the control unit 310CPu or the like to perform counting.

Furthermore, in the above example, the signals for controlling paper transport between the printer 30 and the controller 40 include an enable signal PENB, a paper feed permission signal PRINT, sub-scanning direction synchronization request signals VSREQI and VSREQ2, and sub-scanning direction synchronization request signals VSREQI and VSREQ2. Although synchronization signals VSYNCI and VSYNC2 are used, these signals are not relevant to the subject matter of the present invention. In short, any signal can be used as long as it is a control signal sent and received between the printer and the controller so that the image signal of one color on one page does not overlap with the image signal of other colors on the next page. Good too.

Furthermore, although the above explanation has been about a two-color beam laser printer, the application of the present invention is not limited to two-color lasers, and it goes without saying that it can also be applied to printers that use two or more color laser beams. Nor.

In addition, although the present invention has been described using a laser beam printer, the present invention is not limited to laser beam printers, and may be applied to other electrophotographic printers, such as LED array printers that utilize light emitting diodes, or liquid crystal printers. The present invention can be applied to LCD printers as well.

〔Effect of the invention〕

As described above, according to the present invention, means is provided for detecting the completion of forming a plurality of color images of individual colors on one page of a recording material, and the detecting means detects the Since the formation of the first color image on the next page is not executed until the completion of multiple color images is detected, the data related to the last manually inputted image signal on one page will be transferred to the next page. This eliminates duplication of image signal data that is initially input manually, making it easier for the controller to control the printer.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an example of the relative relationship between the photosensitive drum and the conveying device and the arrangement of paper detection means according to the present invention, and FIG. 2 is a block diagram showing an example of the configuration of a control circuit according to the present invention. , FIG. 3 is a flowchart of the control operation, FIG. 4 is a timing chart between various generated signals used for the control operation, FIG. 5 is a flowchart of the control operation of another form of the present invention, and FIG. Fig. 5 is a timing chart of signals generated by each part used for control operations; Fig. 7 is a configuration diagram showing an example of a conventional two-color laser beam printer; Fig. 8 is a perspective view showing details of its exposure section; FIG. 9 is an explanatory diagram of various signals sent and received between a conventional two-color laser beam printer and a controller, and FIG. 10 is a timing chart between the various signals. l... Photosensitive drum, 2... First semiconductor laser, 3... Second semiconductor laser, 6.7... Charger, 8.9... Developer, lO... Transfer device, 11... Static eliminator, B1.82... Beam detector, LA, L
B... Exposure position, Ll, L2... Raster scanning line, St
... First sensor, B2 ... Second sensor, 21 ... Paper feed cassette, 22 ... Paper feed roller, 23A, 23B ... Conveyance roller, 24
... Transport path, 30 ... Laser beam printer (LBP)
, 31... Control unit, 32.33... Roller clutch, 34.35
... Drive unit, 36.37 ...
Photodiode, 38... Beam detector control circuit, 40... Controller, PENB... Paper feed enable signal, PRINT
... Paper feed permission signal, BDI, BD2 ...
Main scanning direction synchronization signal, VDOI, VDO2-...
Image signal, VSREQI, VSREQ2... Sub-scanning direction synchronization request signal, VSYNCI, VSYNC2...
- Sub-scanning direction synchronization signal. Figure 2/! ! - Invention 10 Kagaro 11' / 5 scarcity diagram of Sojuju Cod ↑ Showing one row of beam printer ↑ Configuration diagram Figure 7

Claims (1)

[Scope of Claims] Performing main scanning on a recording medium at predetermined exposure positions using a plurality of light sources, and performing sub-scanning of the recording medium to sequentially form latent images for each color, In a multicolor printer, a multicolor image is developed from each latent image, and a recording material is conveyed in synchronization with the sub-scanning, so that a multicolor image can be transferred onto the recording material. , a means for detecting that the individual latent images have been formed; a means for generating a start timing of sub-scanning of the recording medium; and a means for detecting that the formation of the individual latent images has been completed by the detecting means. A multi-color printer comprising: means for controlling the recording medium to start sub-scanning by the sub-scanning start timing generating means.