JPH01122853A - Picture forming device - Google Patents

Abstract

PURPOSE:To facilitate detection of missing print and to instantaneously decide a cause, by a method wherein a poor conveyance information signal output means to output a given information signal as to display the content of poor conveyance is provided. CONSTITUTION:When a sheet is conveyed to a picture forming part 3, poor conveyance at some place is detected by means of poor conveyance detecting means 20, 21, and 26, a given information signal distinguished from other poor conveyance is outputted to the picture forming part 3 from a poor conveyance information signal output means 29b. Given poor conveyance is displayed by means of the picture forming part 3. A switching signal is outputted to a discharge sheet switching means 27 from a discharge sheet switching signal output means 29a, and the means 27 is switched so that a sheet related to poor conveyance is discharged in distinction from other sheet. A sheet for which poor conveyance is displayed by means of the picture forming part 3 is discharged through a discharge passage 25 different from that for other sheet, and from display for the sheet, the content of poor conveyance is read.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial application field The present invention is applicable to electrophotography, electrostatic recording, ink sheet, thermal recording, etc., such as laser beam printers, LED printers, and LCS printers used in copying machines, facsimile machines, etc. Regarding image forming devices such as and discharge recording method, please refer to the following for details:
The present invention relates to an image forming apparatus that prints on a sheet using an information signal such as an image information signal.

(0) Prior Art Conventionally, for example, a laser beam printer is a printer that prints on a sheet using an image information signal from an external device.

As shown in FIG. 4, the laser beam printer 1' includes a drum-shaped image carrier 2. It is equipped with an image forming section 3 having a laser optical system 12, etc., a sheet conveying section 5 for conveying sheets to the image forming section 3, and a sheet discharging section 6 for discharging sheets printed by the image forming section 3, A laser beam from a laser optical system 12 that receives an image information signal from an external device 31 forms an image pattern on the tram-shaped image carrier 2 according to the image information signal, and the image pattern on the drum-shaped image carrier 2 is Printing is performed on the sheet conveyed by the sheet conveyance section 5.

(A) Problem to be Solved by the Invention Incidentally, in the above-mentioned laser beam printer 1', there arises a problem of misprinting in which the leading edge of the image and the leading edge of the sheet do not match due to poor sheet conveyance such as skewed feeding of the sheet. However, it is difficult to determine whether there is a sheet conveyance failure just by looking at the printed image, and it is especially difficult to notice skew feeding in graphics, and it is difficult to determine if there is a problem with the printer itself due to sheet conveyance failure, such as skewed sheet feeding. .

Therefore, when a conveyance defect such as skewed sheet feeding, double feeding, or lateral registration abnormality occurs, it is necessary to notify the user or service personnel of the conveyance defect.
For this reason, when a sheet conveyance defect occurs, it may be possible to detect the conveyance defect and eject the misprinted sheet related to the conveyance defect from a special paper ejection path. If the sheet is directly ejected from a special ejecting path, it is difficult to determine whether the misprint is due to skew feeding or double feeding, or which type of conveyance failure is caused.

Therefore, the present invention solves the above-mentioned problems by providing a configuration in which, when a misprint occurs, the details of the conveyance defect that causes the misprint are printed on a sheet, and the sheet is ejected from a special paper ejection path. The purpose is to

(d) Means for solving the problem The present invention has been made in view of the above circumstances, and
Referring to the figure, an image comprising an image forming section (3) that forms an image on a sheet based on an information signal, and a sheet conveying means (5) that conveys the sheet to the image forming section (3). In the forming apparatus (1), the sheet conveying means (5)
a conveyance defect detection means (20, 21, 26) for detecting sheet conveyance defects for each type; and a paper discharge path (24° 25) for discharging the sheet on which an image has been formed in the image forming section (3).
Based on the detection of the conveyance failure by the sheet discharge path switching means (27) that selectively switches the sheet discharge path switching means (27) and the conveyance failure detection means (20, 21, 26), A paper discharge path switching signal output means (2) for transmitting a switching signal to discharge the sheet separately from other sheets.
9a), furthermore, based on the detection of the conveyance failure by the conveyance failure detection means (20° 21.26), the image forming unit (3) sends the sheet related to the conveyance failure to the image forming section (3). The apparatus is characterized in that a conveyance failure information signal output means (29b) is provided for outputting a predetermined information signal differentiated for each type of conveyance failure so as to display the details of the conveyance failure.

(f) Effect Based on the above-described configuration, when a sheet is conveyed to the image forming section (3), if any conveyance failure is detected by the conveyance failure detection means (20, 21, 26), conveyance failure information is displayed. A predetermined information signal related to the conveyance defect, which is distinguished from other conveyance defects, is transmitted from the signal output means (29b) to the image forming section (3), and the image forming section (3) sends an information signal to the sheet related to the conveyance defect. A predetermined transport defect is displayed based on the information signal. Further, a switching signal is transmitted from the paper ejection path switching signal output means (29a) to the paper ejection path switching means (27), and the sheet ejection path switching means (27) distinguishes the sheet related to the conveyance defect from other sheets. The image forming section (
In step 3), the sheet on which a predetermined conveyance defect is displayed is discharged from a different paper discharge path (25) from other sheets, and the content of the conveyance defect is read from the display of the sheet.

3. The above symbols are shown for reference and do not limit the structure in any way.

B) Examples Examples of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the laser beam printer 1 of this embodiment includes an image forming section 3 having a drum-shaped image carrier 2, a sheet conveying section 5 that conveys sheets to the image forming section 3, and an image forming section Ij2. A paper discharge section 6 and the like are provided for discharging the sheets printed by the section 3.

In the image forming section 3, a primary charger 7, a developing device 9, a transfer charger IO, and a cleaner 11 are arranged around the drum-shaped image carrier 2, and a laser optical system 12 and a laser optical system are arranged above the drum-shaped image carrier 2. A reflecting mirror 13 is also arranged. Then, the tram-shaped image carrier 2 rotates in the direction of the arrow and is uniformly charged by the corona discharge of the primary charger 7 to ensure a normal potential. Further, the laser optical system 12 generates a laser beam based on an electric signal of image information from an external device 31 etc., modulates and polarizes the laser beam, and exposes an image pattern on the tram-shaped image carrier 2 via a reflection mirror 13. Then, an electrostatic latent image is formed on the tram-shaped image carrier 2. The electrostatic latent image formed on the tram-shaped image carrier 2 is developed and visualized by toner in a developing device 9, and printed on a sheet conveyed from the sheet conveying section 5 by a transfer charger 10.

Note that the residual toner on the drum-shaped image carrier 2 is removed by the cleaner 1.
Cleaned by 1.

Further, the sheet conveyance section 5 includes a paper feed roller 15 for conveying the sheet to the image forming section 3. A registration roller 16 and a pre-transfer roller 17 are sequentially arranged, and a paper feed sensor 19 is located adjacent to the paper feed roller 15 and detects the presence or absence of a sheet.
, a lateral registration sensor 20 that detects a defect in the lateral registration of a sheet to be conveyed, a left and right sheet leading edge sensor 21 that detects skew feeding, and a double feed detection sensor 26 that is connected to the registration roller 16 and detects double feeding of sheets. has been done.

Further, the paper ejection section 6 includes a paper ejection path 2 for ejecting normal sheets.
4 and a special paper discharge path 2 for discharging sheets related to conveyance defects.
5 are provided, and a deflection plate 27 is disposed at the branching part of these paper discharge paths 24, 25, and is displaced by a drive such as a solenoid to selectively switch these paper discharge paths 24, 25. .

On the other hand, the laser beam printer l is shown in FIGS. 1 and 2.
As shown in detail in the figure, the paper ejection path switching signal output means 29a
, a controller 29 having conveyance failure information signal output means 29b, etc. Then, the paper discharge path switching signal output means 29a sends a paper discharge path switching signal to the solenoid of the deflection plate 27, etc., based on the detection of a conveyance failure by the above-mentioned lateral registration sensor 20, left and right sheet leading edge sensor 21, and double feed detection sensor 26. Then, the deflection plate 27 is switched so that the sheet is guided and ejected to a special ejection path 25. Further, the conveyance failure information signal output means 29b detects each conveyance failure based on the detection of conveyance failures such as lateral registration failure, skew feeding, double feeding, etc. by the above-mentioned lateral registration sensor 20, left and right sheet leading edge sensors 21, and double feeding detection sensor 26. A predetermined information signal differentiated for each type of conveyance defect is transmitted to the laser optical system i2 so that the contents of the information are printed on the sheet related to the conveyance defect.

That is, the information signal for the conveyance defect is determined to print different patterns depending on the type of conveyance defect, such as one line for skew feeding and two lines for double feed.

The operation of the laser beam printer 1 will be explained below.

The laser beam printer 1 waits while the sheet is held between the paper feed rollers 15 of the sheet transport section 5 that transports the sheet, and the leading edge of the sheet is detected by the paper feed sensor 19, and then outside! & vessel 31
When it receives a print signal from the machine, it starts feeding sheets. Then, the sheet is conveyed toward the image forming section 3 by the paper feed roller 15, the registration roller 16, and the pre-transfer roller 17, and is conveyed between the tram-shaped image carrier 2 and the transfer charger 10 to be transferred and charged. The toner image formed on the drum-shaped image carrier 2 is printed by the information signal from the external device 31 in the device 1O, is further conveyed, is fixed in the fixing device, and is ejected from the paper ejection path 24 of the paper ejection section 6. It is papered.

Then, as described above, the sheet is conveyed by the paper feed roller 15, registration roller 16, and pre-transfer roller 17,
When passing the registration roller 16, the lateral registration sensor 20, and the left and right sheet edge sensors 21, the lateral registration sensor 20,
When the left and right sheet leading edge sensors 21 or the double feed detection sensor 26 detect a conveyance defect such as skew, these sensors 20.2
Based on the detection of the conveyance defect in step 1.26, a predetermined information signal corresponding to the detected conveyance defect is transmitted from the conveyance defect information signal output means 29b to the laser optical system 12, and the transfer charger When image information is printed on the sheet related to the conveyance failure in step 10, the content of the conveyance failure is also printed on the sheet. Further, the paper ejection path switching signal output means 2
A switching signal is transmitted from 9a to the solenoid of the deflection plate 27, and the deflection plate 27 is displaced to eject the defective sheet to a special paper discharge path 25, and the defective sheet is transferred to another Special paper ejection path 2 that is distinguished from normal sheets
Paper is ejected from 5.

Therefore, difficult-to-understand misprints can be easily discovered, and the conveyance defect that caused the misprint can be immediately determined.

Note that when a misprint occurs, the laser beam printer l is controlled as shown in FIG.
Receive a misprint cancellation command from and reprint. At this time, whether to print from the misprinted page or from the previous page is determined by the state of the mode bit 71%i of the misprint.

In the above-described embodiment, the conveyance failure information signal output means 29b sends out an information signal such as printing a pattern on the sheet indicating the details of the conveyance failure, but the present invention is not limited to this. In addition to the pattern indicating the date and time, an information signal may also be sent that prints the date and time and a counter at the same time. In this way, not only can the details of the conveyance failure be known from the sheets discharged from the special paper discharge path 25, but also the date and time and amount of prints can be determined, making it easier to troubleshoot.

Further, an information signal may be sent from the conveyance failure information signal output means 29b, such as printing the details of the conveyance failure, date and time, count, 4 & type, etc. on the sheet as a bar code. Unlike,
Information can be expressed in rm* by combining several lines, and later data such as what kind of misprint occurred and when it occurred can be quickly compiled.

Furthermore, although a laser beam printer has been described in the above embodiment, the present invention is not limited to this, and an LED printer that forms an image based on an image information signal, an LC5 (Liquid Cry
The present invention can also be applied to image forming apparatuses such as electrophotographic, electrostatic recording, inkjet, thermosensitive recording, and discharge recording methods such as printers (Stal 5hutter Array) printers.

(g) As described in detail, according to the present invention, based on the detection of sheet conveyance failure by the conveyance failure detection means, the paper discharge path switching means sends out a switching signal so as to switch the conveyance path. Since the paper ejection path switching signal output means and the conveyance defect information signal output means are provided to send out an information signal so as to display the details of the conveyance defect on the image forming unit or the conveyed defective sheet, misprints due to conveyance defects can be avoided. When a misprint occurs, the details of the conveyance defect are displayed on the sheet related to the misprint, and the sheet is ejected from a different paper ejection path from other sheets, so that misprints that are difficult to detect due to the misprint can be easily discovered. In addition, it is possible to immediately determine the nature of the conveyance defect that caused the misprint. Therefore, it becomes easy to deal with any misprint troubles that occur in the apparatus.

[Brief explanation of the drawing]

FIG. 1 is a side view schematically showing a laser beam printer according to an embodiment of the present invention, FIG. 2 is a block diagram thereof, FIG. 3 is a flow chart showing reprinting when a misprint occurs, and FIG. 4 is a conventional laser beam printer. 1 is a side view schematically showing a laser beam printer of FIG. l... Image forming device (laser beam printer) 3.
... Image forming section, 5... Sheet conveyance means (sheet conveyance section), 20, 21.26... Conveyance failure detection means (lateral registration sensor, left and right sheet leading edge sensor, double feed detection sensor), 24, 25 discharge Paper path (sheet discharge path, special sheet discharge path), 27... Paper discharge path switching means (deflection plate), 29a-. Paper discharge path switching signal output means, 29b... transport failure information signal output means.

Claims (1)

[Claims] (1) In an image forming apparatus comprising an image forming section that forms an image on a sheet in response to an information signal, and a sheet conveying means that conveys the sheet to the image forming section, the sheet conveying defect of the sheet conveying means is classified into two types: a conveyance failure detection means for detecting each time; a paper discharge path switching means for selectively switching a sheet discharge path for discharging the sheet on which an image has been formed in the image forming section; and a conveyance failure detection means for detecting a conveyance failure by the conveyance failure detection means. and a sheet discharge path switching signal output means for transmitting a switching signal to the sheet discharge path switching means so as to discharge the sheet associated with the conveyance defect separately from other sheets, based on the sheet discharge path switching means, further comprising: Based on the detection of conveyance failure by the detection means,
A conveyance failure information signal output means is provided to the image forming unit for transmitting a predetermined information signal differentiated for each type of conveyance failure so that the image forming unit displays the details of the conveyance failure on the sheet related to the conveyance failure. An image forming apparatus characterized by the following.