JPH0699624A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent a host side from incorrectly recognizing that a printing operation is completed normally and prevent paper from being consumed wastefully, in the case where troubles of an optical device or a fixing instrument or disorder in nonvolatile memory are generated and image forming operation becomes unable to perform normally. CONSTITUTION:When disorders in an optical device, fixing instrument and nonvolatile memory are detected, paper on this side of a resist sensor 18 to detect the paper to take output timing of image data through an image information processing device 13 is suspended on the spot and after the whole of pieces of the paper passed through the resist sensor 18 are delivered, the whole of carrying operation is suspended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a laser printer or a copying machine, and more particularly to an optical device, a fixing device,
The present invention relates to an image forming apparatus having a function of performing processing when an abnormality occurs in a nonvolatile memory or the like.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus such as a laser printer or a copying machine, an electrostatic latent image is formed on a photoconductor based on image data by an optical device, and the electrostatic latent image is formed by toner. After development, the toner image is transferred to a predetermined paper and fixed by a fixing device to obtain a printed image.

In this image forming apparatus, if an optical device or a fixing device fails or an abnormality occurs in a non-volatile memory that stores various setting conditions, normal printing operation cannot be performed. If the apparatus is stopped immediately when the image forming operation other than the sheet conveyance cannot be performed normally, the processing of the toner on the photoconductor during recovery is difficult. As disclosed in Japanese Laid-Open Patent Publication No. 105166, the printing operation is performed on all the sheets conveyed from the cassette or the tray, and the sheets are discharged, and then the apparatus is stopped.

[0004]

However, when such an abnormal process is performed, the ejected paper is normally processed by the host computer or the image information processing apparatus in the image forming apparatus which sends the print data to the image forming apparatus. In addition, there is a problem that the printing operation is mistakenly recognized as completed. Further, since wasteful printing is performed, there is a problem that paper is wastefully consumed. Further, if a paper sheet with toner enters the fixing device due to a failure of the fixing device, the toner is not fixed to the paper sheet, and the fixing device is soiled.

Therefore, an object of the present invention is to provide a host computer or image information processing when an image forming operation other than sheet conveyance cannot be normally performed due to a failure of an optical device or a fixing device, an abnormality of a non-volatile memory or the like. It is possible to prevent the device from erroneously recognizing that the printing operation has finished normally, to prevent wasteful consumption of paper, and to prevent toner from adhering to the fixing device when the fixing device fails. To provide a device.

[0006]

An image forming apparatus of the present invention includes an image data output unit for outputting image data, and an image recording unit for recording an image on a sheet based on the image data from the image data output unit. Means, a paper conveying means for conveying the paper from the paper feeding section to the image recording means, and a paper for recording the image-recorded paper from the image recording means to the discharge section, and the image data output means for transmitting the image data to the image recording means. In order to take the timing of outputting, a sheet detecting unit that detects that the sheet conveyed by the sheet conveying unit has reached a predetermined position, and an abnormality detecting unit that detects an abnormality in the image forming operation other than the sheet conveyance, When an abnormality is detected by the abnormality detecting unit, the sheet conveying unit is controlled so that the sheet before reaching the sheet detecting unit is stopped on the spot and passed through the sheet detecting unit. Paper is one which includes an abnormality processing means for discharging.

In this image forming apparatus, the sheet is conveyed from the sheet feeding section to the image recording section by the sheet conveying section, and the image data output section transfers the image data to the image recording section in accordance with the timing when the sheet detecting section detects the sheet. Is sent, and an image is recorded on the paper by the image recording means based on the image data. Further, when the abnormality detection unit detects an abnormality in the image forming operation other than the sheet conveyance, the abnormality processing unit stops the sheet before reaching the sheet detection unit on the spot, and the sheet passing through the sheet detection unit is not detected. Is discharged.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 relate to a first embodiment of the present invention.

FIG. 2 is an explanatory view showing a schematic configuration of the laser printer of this embodiment. This laser printer includes a photoconductor 6 on which an electrostatic latent image is formed, and an optical device 1 which irradiates the photoconductor 6 with a light beam that blinks based on image data to form the electrostatic latent image. I have it.

The optical device 1 is provided with a semiconductor laser (not shown) that modulates and outputs laser light according to image data. A laser beam emitted from this semiconductor laser enters a polygon mirror 2 and is deflected according to the rotation of the polygon mirror 2. After the deflected laser beam passes through the Fθ lens 3, the traveling direction is changed by the mirrors 4 and 5, and the photoconductor 6 is irradiated with the deflected laser beam.

Around the photoreceptor 6, a charge roll (not shown), a developing device 9, a transfer roll (not shown), and a cleaning device 10 are provided. Photoconductor 6
Is rotating at a constant speed. First, the surface of the photoconductor 6 is uniformly charged by the charge roll, and the charged photoconductor 6 is irradiated with a laser beam, so that the surface of the photoconductor 6 is converted into image data. A corresponding electrostatic latent image is formed. This electrostatic latent image is developed by the developing device 9 to form a toner image. This toner image is transferred onto a sheet by a transfer roll. The toner remaining on the surface of the photoconductor 6 after the transfer is removed by the cleaning device 10.

Behind the optical device 1, a power source section 11, a control device 12 for controlling the entire laser printer, and image information sent from a host computer is translated into the language of the laser printer and sent to the control device 12. An image information processing device 13 for sending is provided.

Next, the paper transport path will be described.
At the bottom of the laser printer, a removable paper cassette 1
4 are provided. The uppermost sheet of the sheets stacked in the sheet feeding cassette 14 is sent out of the sheet feeding cassette 14 by a half-moon shaped feed roll 15. A turn roll 16 and a registration roll 17 are provided in this order from the side of the paper feed cassette 14 in the conveyance path from the paper feed cassette 14 to the photoconductor 6. The rotation of the turn roll 16 is stopped by an electromagnetic clutch. Further, in the vicinity of the registration roll 17, a registration sensor 18 for detecting that the leading edge of the paper has reached the position of the registration roll 17 is provided so that the image information processing device 13 can output the image data.

The sheet sent out from the sheet feeding cassette 14 travels along the path indicated by the broken line by the turn roll 16 and the leading edge of the sheet reaches the registration roll 17.
8 to detect. Then, based on the detection timing of the registration sensor 18, the image information processing device 13 outputs the image data. In this way, the sheet passes between the photoconductor 6 and the transfer roll at a desired timing. At this time, the toner image on the photoconductor 6 is transferred onto the paper. The transferred sheet is separated from the surface of the photoconductor 6 and is conveyed to the discharge port by the registration roll 17.
An exit roll 20 is provided at the discharge port, and a fixing device 19 is provided in front of the exit roll 20. The fixing device 19 includes, for example, a pair of a heat roll controlled to a constant high temperature and a pressure roll that presses the paper against the heat roll. In addition, an exit sensor 21 is provided near the exit roll 20 to detect that the printed paper has been ejected from the laser printer.

FIG. 3 shows the above-mentioned sheet conveying path and devices on the way.

FIG. 1 is a block diagram showing a configuration relating to abnormality processing of the laser printer of this embodiment. As shown in this figure, the controller 12 is a central processing unit (hereinafter, CPU).
Is written. ) 31 and a counter A32 connected to the CPU 31. The CPU 31 includes a read only memory for storing programs and a random access memory as a working area.
Although a non-volatile memory 33 connected to the CPU 31 is provided in the control device 12, in FIG.
This non-volatile memory 33 is shown outside the control device 12. The non-volatile memory 33 includes the resolution and the optical device 1.
It stores various setting conditions of the laser printer, such as the output adjustment value of the semiconductor laser and the adjustment value of the registration. The counter A32 is for storing the number of sheets between the registration sensor 18 and the discharge port, and is incremented when the registration sensor 18 is turned on and subtracted when the exit sensor 21 is turned off.

The control device 12 receives image data and control data from the image information processing device 13 and sends a status to the image information processing device 13. Further, the control device 12 inputs each output of the registration sensor 18 and the exit sensor 21, and controls the feed roll 15, the turn roll 16, and the registration roll 17.

Further, in this embodiment, an abnormality detecting means 34 for detecting a failure of the optical device 1, the fixing device 19 and an abnormality of the non-volatile memory 33 is provided. The abnormality detecting means 34 is realized by the CPU 31 in the control device 12. The abnormality detecting means 34 detects an abnormality as follows, for example. In the case of the optical device 1, for example, using the output of a sensor that detects the laser beam deflected by the polygon mirror 2, the rotational speed of the polygon mirror 2 is obtained from the interval of the output of this sensor, and this rotational speed is the set value. When it is detected that it is not, it is judged as abnormal. In the case of the fixing device 19, for example, when the output of a sensor that detects the temperature of the heat roll is used to detect that the temperature of the heat roll is not within the set temperature range, or when the heater is disconnected. It is judged abnormal. Further, in the case of the non-volatile memory 33, for example, when writing is impossible, or when the same data is written in a plurality of places and they do not match, it is determined to be abnormal.

When an abnormality is detected by the abnormality detecting means 34, the control device 12 stops the paper before reaching the registration sensor 18 on the spot and carries out an abnormality processing to eject the paper passing through the registration sensor 18.

Next, this abnormality processing will be described.

FIG. 4 is a timing chart showing the state of each sensor and the counter A and the timing of occurrence of an abnormality when printing is performed by a print command or the like from the image information processing device 13. This figure shows the case where two sheets are printed continuously. (A) shows a drive command for the feed roll.
As shown in (e), the abnormality occurrence timing before the drive command for the first feed roll is set to P1.

The drive of the feed roll 15 is started in response to the drive command of the feed roll, the sheet is conveyed by the turn roll 16, and after a predetermined time, the registration sensor 18 is turned on as shown in (b). Until this time, (d)
As shown in, the value of the counter A32 is "0". The abnormality occurrence timing from the first feed roll drive command to the time when the registration sensor 18 is turned on is P2.

After that, when the first sheet reaches the exit sensor 21, the exit sensor 21 is turned on, and then the registration sensor 18 is turned off, as shown in (c). Cash register 1
A second feed roll drive command is issued immediately before 8 is turned off, and the registration sensor 18 is turned on again after a predetermined time. Next, the outlet sensor 21 is turned off. The value of the counter A32 is "1" from the first time the registration sensor 18 is turned on to the second time the registration sensor 18 is turned on, and the counter A32 is from the second time the registration sensor 18 is turned on to the first exit sensor 21 is turned off. Has a value of "2". Then, the abnormality occurrence timing from the first turning on of the registration sensor 18 to the second feed roll driving command is set to P3, and then the abnormality occurrence timing from the second turning on of the registration sensor 18 is set to P4, and then The abnormality occurrence timing before the first turning off of the outlet sensor 21 is set to P5.

After the outlet sensor 21 is turned off for the first time, 2
The second exit sensor 21 is turned on, the second registration sensor 18
Is turned off and the exit sensor 21 is turned off for the second time. When printing two sheets, 2 from the first feed roll drive command.
The period until the exit sensor 21 is turned off is "printing". The value of the counter A32 is "1" from the first turning off of the outlet sensor 21 to the second turning off of the outlet sensor 21, and the abnormality occurrence timing during that time is P6. The value of the counter A32 is "0" after the second outlet sensor 21 is turned off, and the abnormality occurrence timing at that time is P7.

In the abnormality processing, different processing is performed according to the abnormality occurrence timings P1 to P7 shown above. When printing three or more sheets in succession, if the registration sensor 18 is turned on in the middle of P6, it will be P5 again, and thereafter P5 and P6 will be repeated, and the end will be P7.

FIG. 5 is a flow chart showing the abnormality processing in this embodiment. As shown in this figure, in this abnormality processing, first, at step (hereinafter referred to as S) 101, the abnormality occurrence timing is determined. This judgment is based on the control device 1
The timing at which the CPU 31 in FIG. 2 detects an abnormality by the abnormality detecting means 34 based on the timing of the feed roll drive command, the value of the counter A32, and the state of the registration sensor 18 is P1 to P7 in FIG. One of the above is determined. Then, according to this determination, in the case of P1 or P7, the process A is executed in S102, in the case of P2, the process B is executed in S103, in the case of P3 or P6, the process C is executed in S104, and in the case of P4. The process D is executed in S105, and in the case of P5, the process E is executed in S106, and the process ends.

FIGS. 6A to 6E are flowcharts showing the processes A to E in FIG. 5, respectively.

In process A, the print operation is disabled in step S111 and the process returns. That is, in the case of the abnormality occurrence timing P1 or P7 in which the process A is performed, it is not “printing”, there is no sheet in the transport path, and the sheet transport operation is not performed. There is no. Here, the print operation disable setting is a setting for notifying the image information processing device 13 that the normal print operation cannot be performed, and when the image information processing device 13 side requests, Returns the print operation disable setting as the status.

In process B, the printing operation is disabled in S121, the turn roll 16 is stopped in S122, and the main motor for driving each roll including the registration roll 17 is stopped and returned in S123. That is, at the abnormality occurrence timing P2 when the process B is performed, there is a sheet before the registration sensor 20 and there is no sheet after the registration sensor 20, so the turn roll 16 is stopped and the sheet before the registration sensor 20 is stopped on the spot. After that, all transport operations are stopped.

In process C, the printing operation is disabled in S131, and then in S132, the exit sensor 21 is turned off.
When it is turned off, the main motor is stopped and returned in S133. That is, the abnormality occurrence timing P at which the process C is performed
In the case of 3 or P6, there is no sheet in front of the registration sensor 20, and there is one sheet after the registration sensor 20,
After the paper after the registration sensor 20 is discharged, all the transport operations are stopped.

In process D, the print operation is disabled in S141, the turn roll 16 is stopped in S142, the exit sensor 21 is awaited in S143, and when it is turned off, the main motor is stopped in S144. And then return. That is, in the case of the abnormality occurrence timing P4 for performing the process D,
Since there is a sheet before the registration sensor 20 and one sheet after the registration sensor 20, the turn roll 16 is first stopped to stop the sheet before the registration sensor 20 on the spot, and after the sheet after the registration sensor 20 is discharged. , Stop all transport operations.

In process E, the printing operation is disabled in step S151, and then the exit sensor 21 is turned off in step S152.
When it is turned off, the exit sensor 21 is awaited again in step S153, and when it is turned off, the main motor is stopped and returned in step S154. That is, at the abnormality occurrence timing P5 when the process E is performed, there is no sheet in front of the registration sensor 20,
Since there are two sheets of paper after the registration sensor 20, all the conveying operations are stopped after both sheets of paper after the registration sensor 20 have been discharged.

As described above, in this embodiment, the abnormality detecting means 3
4, the optical device 1, the fixing device 19, the non-volatile memory 3
When the abnormality of No. 3 is detected, the paper in front of the registration sensor 18 is stopped on the spot, and after all the paper that has passed the registration sensor 18 is discharged, all the conveying operations are stopped. It is possible to reduce false recognition that the device 13 determines that the printing operation is normally completed. Further, since the number of sheets discharged due to an abnormal printing result is reduced, it is possible to reduce wasteful consumption of sheets. Furthermore, since the number of sheets of paper that enter the fixing device 19 is reduced due to the failure of the fixing device 19, the adhesion of toner to the fixing device 19 can be reduced.

Next, a second embodiment of the present invention will be described. The present embodiment has the same configuration as the first embodiment, and is different only in the abnormality processing.

FIG. 7 is a flow chart showing the abnormality processing in this embodiment. In this abnormality processing, first, in S201
In step S202, the print operation is disabled, and in step S202, it is determined whether or not printing is in progress. It should be noted that “during printing” refers to the period from the first feed roll drive command until the last sheet passes through the exit sensor 21 and the exit sensor 21 is turned off. If not printing, the process ends. If printing is in progress, the turn roll 16 is stopped in S203. That is, the turn roll 16 is stopped regardless of whether or not there is a sheet in front of the registration sensor 18. Next, in S204, the value of the counter A32 is "0".
Determine whether or not. In the case of "0", the main motor is stopped in S205 and the process ends. If not "0", S20
In step 6, the exit sensor 21 is awaited to be turned off, and when it is turned off, the value of the counter A32 is decremented by "1" in step S207, and the process returns to step S204. In this way, S204 to S20
By repeating step 7, all sheets of paper after the registration sensor 18 are discharged, and when the value of the counter A32 becomes "0", the main motor is stopped in S205 and the process ends.

In this embodiment, it is not necessary to judge the timing of occurrence of abnormality as in the first embodiment, and therefore the processing is simplified.

Other functions and effects are similar to those of the first embodiment.

[0038]

As described above, according to the present invention, when the abnormality detecting means detects an abnormality in the image forming operation other than the sheet conveyance, before reaching the sheet detecting means for timing the output of the image data. Since all the sheets of paper are stopped on the spot and all the sheets of paper that have passed through the sheet detection means are discharged, it is possible to reduce misidentification that the host computer or the image information processing apparatus determines that the printing operation is normally completed. There is an effect. Further, according to the present invention, since the number of sheets discharged due to an abnormal printing result is reduced, it is possible to reduce wasteful consumption of sheets. Further, according to the present invention, since the number of sheets of paper which enter the fixing device is reduced due to the failure of the fixing device due to the failure of the fixing device, it is possible to reduce the adhesion of toner to the fixing device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration relating to abnormality processing of a laser printer according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a schematic configuration of a laser printer of a first embodiment.

FIG. 3 is an explanatory diagram showing a sheet conveyance path in the laser printer of FIG. 2 and devices and the like in the middle thereof.

FIG. 4 is a timing chart showing a state of each sensor and a counter A and an abnormality occurrence timing in the first embodiment.

FIG. 5 is a flowchart showing an abnormal process in the first embodiment.

6 is a flowchart showing processes A to E in FIG.

FIG. 7 is a flowchart showing anomaly processing in the second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical device, 6 ... Photoconductor, 12 ... Control device, 13 ... Image information processing device, 15 ... Feed roll, 16 ... Turn roll, 17 ... Registration roll, 18 ... Registration sensor, 19 ...
Fixing device, 21 ... Exit sensor, 31 ... CPU, 32 ... Counter A, 33 ... Nonvolatile memory, 34 ... Abnormality detecting means

Claims (1)

[Claims] 1. An image data output unit for outputting image data, an image recording unit for recording an image on a sheet based on the image data from the image data output unit, and a sheet for feeding the image from the sheet feeding unit. While transporting to the means,
A sheet conveying unit that conveys the image-recorded sheet from the image recording unit to the discharge unit; and a sheet conveying unit that controls the timing of the image data output unit outputting image data to the image recording unit. Paper detection means for detecting that the conveyed paper has reached a predetermined position, abnormality detection means for detecting an abnormality in image forming operation other than paper conveyance, and when abnormality is detected by this abnormality detection means, An image including: an abnormality processing unit that controls the sheet conveying unit to stop the sheet before reaching the sheet detecting unit on the spot and eject the sheet that has passed the sheet detecting unit. Forming equipment.