JP2002244495A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device which is capable of more accurately detecting the amount of toner consumption while conducting the detection of the amount from the accumulated number of black pixels being written into a photosensitive body. SOLUTION: When an instruction to perform a copying operation is given in an electrophotographic system type image forming device, a conversion value corresponding to the writing resolution of an output page is obtained from a storage device (201) or the conversion value corresponding to the remaining amount of toner at that time is obtained from the storage device (202), the obtained values are set into an LUT (203) and the computed value of the counter is cleared when a page is outputted (204). When image data to be outputted are generated, individual image data corresponding to each pixel are given to the LUT, the data are converted into the equivalent value of the amount of toner consumption corresponding to individual image data and accumulated into the counter (205).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus used for a digital copying machine, a printer, and the like, and more particularly, to an image forming apparatus for calculating toner consumption by counting the number of black pixels written on a photosensitive member. Related to the device.

[0002]

2. Description of the Related Art In an image forming apparatus such as a laser printer, a digital copying machine, or a plain paper facsimile apparatus, which records by attaching toner to paper in accordance with image data, the number of dots of black pixels written on a photosensitive member is added. Detect toner consumption by accumulation. In performing such pixel count, how much toner is consumed for writing one pixel is converted using a reference table (look-up table, LUT) and added to the count value thus far. The method of seeking is known. As such a conventional technique, for example, a technique disclosed in Japanese Patent Application Laid-Open No. 07-175368 is cited.

[0003]

However, in the prior art, including the technique disclosed in Japanese Patent Application Laid-Open No. H07-175368, the amount of toner consumed per pixel is determined by the writing resolution, the remaining amount of toner, or each pixel. Fluctuating due to the positional relationship with the neighboring pixels of
There is a problem that an accurate toner consumption cannot be known.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problem, and it is possible to select an LUT from a plurality of LUTs in accordance with the size of a writing resolution or a result of detection of a remaining amount of toner and obtain an added value of a pixel count. An object is to obtain a more accurate addition value regardless of the resolution. It is another object of the present invention to more accurately obtain an added value for an isolated / fine line / dense pixel by recognizing the relationship between each pixel to be written and an adjacent pixel.

[0005]

According to the first aspect of the present invention, a latent image of image data developed in the form of a bit map is written on a photosensitive member and developed using toner. An image forming apparatus of an electrophotographic system for outputting an image by means of the image forming apparatus, comprising means for counting the number of pixels to be written during the image output, wherein a predetermined addition corresponding to the value of the multi-valued image data is performed at the time of counting. In the image forming apparatus which acquires the amount from the reference table, the value of the reference table is changed according to the output resolution.

According to a second aspect of the present invention, an image forming apparatus of an electrophotographic system in which a latent image of image data developed in a bitmap form is written on a photoreceptor and developed by using toner to output an image. An image forming apparatus, comprising: means for counting the number of pixels to be written during the image output, and at the time of counting, acquiring a predetermined addition amount corresponding to the value of multi-valued image data from a reference table.
A position recognizing means for recognizing a positional relationship between each pixel of the output data and a peripheral pixel is provided, and a reference location of the reference table is changed according to a positional relationship between the pixel and the peripheral pixel.

According to a third aspect of the present invention, an electrophotographic image forming apparatus that writes a latent image of image data developed in a bitmap form on a photosensitive member and develops the image using toner to output an image. An image forming apparatus, comprising: means for counting the number of pixels to be written during the image output, and at the time of counting, acquiring a predetermined addition amount corresponding to the value of multi-valued image data from a reference table.
A configuration is provided in which a remaining amount detecting unit for detecting the remaining amount of toner is provided, and the value of the reference table is changed according to the remaining amount of toner.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image forming apparatus to which the present invention is applied will be described below. FIG. 1 is a block diagram showing a system configuration of a digital copying machine in which the present invention is implemented. As shown, the digital copier includes an engine control unit 101, a scanner unit 102, an image processing unit 103, a writing unit 104, various sensors 10
5. It is composed of a sequence device group 106, and it is also possible to output an image not only from the scanner unit 102 but also from an application unit 108 such as a printer or a facsimile.

In the digital copying machine having such a configuration, when a user gives a copy instruction, the scanner unit 102 reads a document and the image processing unit 10
3 to transfer the image data. The image processing unit 103 performs image quality adjustment, scaling, and the like.
Send the processed data to The writing unit 104 drives the laser element according to the received data, and performs optical writing on the photoconductor. These operations are controlled by the engine control unit 101 based on inputs from various sensors 105, and the sequence device group 1 such as a photoconductor and a fixing unit
06 is similarly controlled by the engine control unit 101 to form an image on recording paper. Note that the user's instruction is given by the operation panel 107, and the engine control unit 10
It is conveyed to 1.

FIG. 2 is a block diagram of a main part of the image processing unit, which is provided at the last stage of the image processing unit 103 and shows the first embodiment of the present invention. The conversion value obtained by giving multi-valued image data corresponding to each pixel to the LUT 111 is input to an adder or a counter, and
Alternatively, a cumulative pixel count value (toner consumption amount) is obtained. FIG.
In the example of the above, by inputting the image data to the address input terminal of the LUT 111, the converted value of the image data previously stored in the LUT 111 is output, the value is set in the adder 112, and the set value and Adder 1
When the lower bits remaining in 13 are added to carry (upper bit), the carry causes the counter 114 to count up. This counter output value is the accumulated pixel count value. FIG. 5 shows an example of the LUT.

The operation of the first embodiment of the present invention will now be described with reference to FIG.
This will be described with reference to the flowchart shown in FIG. First, a copy operation is instructed by the user, whereby the image processing unit 101 obtains a conversion value corresponding to the writing resolution of the output page from the storage device (201), or responds to the remaining toner amount at that time. The conversion value is obtained from the storage device (202), and the obtained value is set in the LUT 111 (203). When clearing the pixel count value for each output page, the counter 114 is used at the start of page output.
Is cleared (204).

Then, the image data read by the scanner unit 102 is sent to the image processing unit 103. Alternatively, when a facsimile output or a printer output is instructed by a mounted application, image data is sent from the corresponding application unit 108 to the image processing unit 103. Image processing unit 10
In step 3, density adjustment, scaling, image quality correction, and the like are performed, and image data to be sent to the writing unit 104 is generated. Then, the image data is given to the LUT 111, converted into a toner consumption equivalent value corresponding to each image data, and added to the counter 114 (205).

At the end of the page output or during the operation, the toner supply control, the remaining toner amount display, the integrated toner consumption amount display and the like are performed as necessary based on the accumulated value of the counter 114. The writing unit 104 turns on the laser diode according to the transferred image data, and performs optical writing on the photoconductor. In synchronization with this, the engine control unit 10
Reference numeral 1 drives an electrophotographic process sequence device group 106 such as a paper feeding unit, a charging unit, a developing unit, a transfer unit, and a fixing unit to form an image on a recording sheet.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the LUT settings are not changed,
First, the counter 114 is reset (207), and when writing of a new page starts (208), the positional relationship between the pixel (black pixel) of the image data generated by the image processing unit 103 and its surrounding pixels is checked. (209) Based on the positional relationship, the image data relating to the reference location of the LUT is corrected by the method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 07-175368, and the pixel count value corresponding to the positional relationship with the adjacent pixel is calculated. (210).

In this embodiment, a digital copying machine has been described as an example of an image forming apparatus. In addition, various optical printers such as a laser printer, an LED printer, and a liquid crystal printer, and a bitmap form such as a plain paper facsimile apparatus can be developed. The present invention can be similarly applied to other apparatuses for forming an image.

[0016]

As described above, according to the present invention,
According to the first aspect of the present invention, in the electrophotographic image forming apparatus, when the predetermined addition amount corresponding to the value of the multi-valued image data is obtained from the reference table and the number of write pixels is counted, the reference table is used. Is changed according to the output resolution, so that more accurate toner consumption can be obtained regardless of the difference in resolution.

According to the second aspect of the present invention, in the electrophotographic image forming apparatus, a predetermined addition amount corresponding to the value of the multi-valued image data is obtained from the reference table and the number of pixels to be written is counted. At this time, the positional relationship between each pixel of the output data and the peripheral pixel is recognized, and the reference location in the reference table is changed according to the positional relationship between the pixel and the peripheral pixel. Irrespective of the positional relationship, the more accurate toner consumption can be obtained.

According to the third aspect of the present invention, in the electrophotographic image forming apparatus, a predetermined addition amount corresponding to the value of the multi-valued image data is obtained from the reference table and the number of write pixels is counted. At this time, the value of the reference table is changed according to the remaining amount of toner, so that a more accurate amount of consumed toner can be obtained according to the change of the remaining amount of toner.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system configuration of a digital copying machine in which the present invention is implemented.

FIG. 2 is a block diagram of a main part of the image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is an operation flowchart of a main part of the image forming apparatus according to the first embodiment of the present invention.

FIG. 4 is an operation flowchart of a main part of an image forming apparatus according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of a main part of the image forming apparatus according to the first embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 101 engine control unit 102 scanner unit 103 image processing unit 104 writing unit 111 lookup table 112 adder 113 adder 114 counter

Claims (3)

[Claims] 1. An electrophotographic image forming apparatus for writing a latent image of image data developed in a bitmap shape on a photoconductor and developing the image using toner, and outputting the image. Means for counting the number of pixels to be written therein. In the image forming apparatus for obtaining a predetermined amount of addition corresponding to the value of the multi-valued image data from the reference table at the time of counting, the value of the reference table is output to the output resolution. An image forming apparatus characterized in that the image forming apparatus is configured to change in accordance with the condition. 2. An electrophotographic image forming apparatus for writing a latent image of image data developed in a bitmap shape on a photosensitive member and developing the image using toner, and outputting the image. In the image forming apparatus provided with means for counting the number of pixels to be written, and at the time of counting, a predetermined addition amount corresponding to the value of the multi-valued image data is obtained from the reference table, An image forming apparatus comprising a position recognizing means for recognizing a positional relationship between a peripheral pixel and a peripheral pixel, and changing a reference location of the reference table in accordance with a positional relationship between the pixel and the peripheral pixel. 3. An electrophotographic image forming apparatus for writing a latent image of image data developed in a bitmap shape on a photosensitive member and developing the latent image using toner, and outputting the image. In the image forming apparatus, a means for counting the number of pixels to be written is provided, and at the time of counting, the remaining amount of toner is detected in an image forming apparatus that acquires a predetermined addition amount corresponding to the value of multi-valued image data from a reference table. An image forming apparatus comprising an amount detecting unit, wherein a value of the reference table is changed according to a remaining amount of toner.