JPS63167384A - Image forming device - Google Patents

Abstract

PURPOSE:To easily check the function by a printer unit by providing a video controller with a test pattern storing means storing plural kinds of test patterns. CONSTITUTION:The test pattern ROMs 65, 66 have 64K capacity e.g. and store different kinds of test patterns to be the repeat of short areas consisting of e.g. 512X128 bits. Respective outputs from the test pattern ROMs 65, 66 are inputted to a multiplexer 67. The test pattern ROMs 65, 66 inputs a pattern select signal applied from a dip switch e.g. directly or through an inverter 68 to select either one of the signals. A video control part 69 applies a reading address to these test pattern ROMs 65, 66. Consequently, function check can be easily executed by the printer unit without using a printer controller.

Description

[Detailed description of the invention] Change of arrangement The present invention relates to an image forming apparatus such as a laser printer.

凭】u【Trap Generally, an image forming device such as a laser printer has a test pattern for checking the function of the printer itself, but the test pattern for only the printer without using a printer controller is a repeating pattern of two black and white dots. Therefore, even if an image abnormality occurs, it is inconvenient that the abnormal location cannot be determined depending on the test pattern.

In this case, if you have a printer controller, you can consider equipping it with various test patterns, but this would add factors to the printer controller itself in addition to the factors of the printer itself, making it difficult to determine the abnormality. .

Purpose This invention has been made in view of the above points, and an object thereof is to make it possible to easily check the functions of a printer alone.

Configuration In order to achieve the above object, the present invention provides a video controller with test pattern storage means that stores a plurality of types of test patterns.

Hereinafter, a detailed explanation will be given based on one embodiment of the present invention.

FIG. 1 is a schematic configuration diagram showing an example of a laser printer as an image forming apparatus embodying the present invention.

In this laser printer, a belt-shaped photoreceptor 1 is rotated in the direction of the arrow when a print is started. At this time, the surface of the photoreceptor 1 is uniformly charged by a charging charger 2, and then a written image is written by an optical writing device 3. A corresponding laser beam is emitted onto the photoconductor 1 to scan the photoconductor 1 (main scanning), and by scanning the photoconductor 1 with this laser beam and rotating the photoconductor 1 in the direction of the arrow (sub-scanning). , an electrostatic latent image corresponding to a written image is formed on the photoreceptor 1, and then toner is applied to the electrostatic latent image on the photoreceptor 1 by a developing device @4 to visualize it as a toner image.

On the other hand, the uppermost sheet of the sheets placed and held in the selected sheet feed tray of the sheet feed tray 5 or the sheet feed tray 6 is taken out by the sheet feed roller 7.8, and the sheet feed roller 10, 11
The roller is fed up to the registration roller 12 and stopped once.

Then, the registration roller 12 is rotated at a predetermined timing to feed the paper to the transfer section.

After applying a predetermined voltage to the transfer charger 14 at a predetermined timing to transfer the toner image on the photoreceptor 1 onto the paper,
The paper is separated from the photoreceptor 1 by corner separation and sent to a fixing device 15, where the toner image is fixed onto the paper by hot roll fixing.

Thereafter, the sheet on which the fixing process has been completed is reversed by a reversing unit 16 and is ejected face down from a sheet ejection roller 17 onto a sheet ejection stacker integrally formed as a part of a cover 18.

On the other hand, the charge remaining on the photoreceptor 1 is removed by a static eliminator 21, and the toner remaining on the photoreceptor 1 is removed by a cleaning device 22 in preparation for the next image forming process.

FIG. 2 is a block diagram showing the control section and power supply section of this laser printer.

AC voltage from a commercial power source is applied to a power transformer 33 via a main switch 31 and a noise filter 32 to step down the voltage, and the secondary voltage of this power transformer 33 is supplied to a DC power circuit 34. From this DC power supply circuit 34 to the switch 3
Power is supplied to the fixing controller 37 that drives and controls the fixing motor 36 and the developing motor controller 3 that drives and controls the developing motor 38 through the controller 5. Also, power is supplied to a high voltage section 42 for applying high voltage to the corona and charger wires 41 via the interlock switch 40 . Note that an interlock switch 43 is provided on the primary side of the power transformer 33.
A fixing heater 44 and a high-speed solid state relay (SSR) 45 are inserted through the.

On the other hand, the control section includes a sequence controller 47 and a video controller 48. sequence controller 4
7, solenoids, motors 51, various controllers 5
2. Data is transmitted and received between the sensors 53 and the video controller 48 to execute sequence control of the image forming process described above. The video controller 48 controls the optical unit 55 of the optical writing device 3 to control writing of images onto the photoreceptor 1 based on video data (dot pattern) given from a printer controller serving as an image processing controller (not shown).

FIG. 3 is a block diagram showing this video controller 48.

The memory control unit 61 stores the video data DA when the active low offline signal OFF LINE is at °H°.
Input TAO, DATAI, write clock WCLK, and line gate signal LGATE via the input section 62,
A to the AOM (audio optical modulation) of the optical unit 55 via the output section 63
OM data AOM DATA is output, and when the offline signal OFF LINE becomes L°, the AOM data AOM DAT is output as a repeating dot pattern based on the test pattern data from the multiplexer 67.
Output A.

The test pattern ROMs 65 and 66 have a capacity of, for example, 64 and store different types of test patterns, for example repeating short areas of 512 x 128 bits. Each output of these test pattern ROMs 85 and 88 is output to a multiplexer 67. In addition, these test pattern ROMs 65 and 68 are, for example, DIP (DIP).
P) Either one is selected by inputting the pattern select signal given from the switch directly or by inverting it with the inverter 68. The video control section 6 gives read addresses to these test pattern ROMs 65 and 86.

Next, the operation of this embodiment configured as described above will be explained with reference to FIG. 4 and subsequent figures.

First, under normal conditions when the offline signal OFF LINE is set to "H", print data from the host is converted into video data (pattern data) by a printer controller (not shown) and given to the video controller 48, and is stored in the memory of the video controller 48. Since the control unit 81 selects the video data DATAO and DATAI and outputs AOM data based on the video data to the optical unit 55, the image provided from the host side is printed.

In contrast, the offline signal OFF LINE is
By setting it to L°, the test pattern ROM65.
The test pattern data selected by the pattern select signal in 86 is repeatedly given to the memory control unit 61,
This memory control section 61 outputs AOM data based on this test pattern data to the optical unit 55, so that the test pattern is printed.

Here, by using a test pattern as shown in FIG. 4, for example, it is possible to comprehensively check the conditions surrounding the process, such as density unevenness, single dot reproducibility, and background stains. Furthermore, by using a test pattern such as that shown in FIG. 5, it is possible to check conditions surrounding the optical system, such as single dot reproducibility, jitter, and image wobbling.

Therefore, by storing these two types of test patterns in the test pattern ROM 85.66, it is possible to select the most suitable one according to one function check and perform test printing.

In addition, as a test pattern, for example, a grid pattern as shown in Fig. 6 or a mesh pattern as shown in Fig. 7 can be used. can be used to check. Furthermore, by using a test pattern of numbers, letters, etc., it is possible to check the actual printing condition.

In this way, in this laser printer, since the video controller is equipped with a test pattern storage means that stores a plurality of types of test patterns, it is possible to easily check the functionality of the printer alone without using a printer controller.

Effects As explained below, according to the present invention, it is possible to easily check the functions of the printer alone.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an example of an image forming apparatus embodying the present invention; FIG. 2 is a block diagram showing a control section and power supply section thereof; FIG. 3 is a block diagram showing a video controller thereof; 4 to 7 are explanatory diagrams showing different examples of test patterns. 4th...Video controller 61...Memory control unit 85.68...Test pattern ROM hole! J8μ7 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1. In an image forming apparatus having a video controller that controls an optical writing device based on pixel data sent from an image processing controller, the video controller is provided with test pattern storage means storing a plurality of types of test patterns. Features of the image forming device.