JPH04330472A - Toner replenishing method for printer - Google Patents

Abstract

PURPOSE:To provide a printer whose printing density is not changed whatever shape a recorded image has. CONSTITUTION:According to image data from a data input equipment, a latent image corresponding to the image data is formed on a photsensitive body and the toner of a quantity corresponding to the latent image is supplied from a developing device to form the recorded image, and the developing device is replenished with the toner of a quantity corresponding to the supplied toner quantity in this toner replenishment method for a printer. The ratio of the counted number of the image data to the edge counted number of a changing point where a white picture element is changed into a black picture element is calculated, and the replenishment of the toner with which the developing device is replenished is performed based on the calculated ratio.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer using xerography, and more particularly to a printer with stable printed image density and a method of replenishing toner to a developing device of the printer.

0002

2. Description of the Related Art Printers using xerography include a backlight method and an image light method as exposure methods for a photoreceptor. In these printers, the number of image data (black pixels) (hereinafter sometimes referred to as the image count number) is sent to the developing device according to the following equation (5).
Toner is replenished in an amount proportional to .

[0003] Toner supply amount = K1 × (image count number)
(5) However, K1 is a constant.

0004

Conventionally, the amount of toner supplied to a developing device of a printer is proportional to the amount of toner consumption, that is, the number of black pixels. However, even when a recorded image is formed using black pixels having the same number of dots, that is, even when the amount of toner replenishment is the same, the amount of toner consumed per unit dot may differ depending on the shape of the recorded image. Moreover,
The print density of an image with many black pixels consisting of isolated points, that is, many black pixels surrounded by white pixels, will be darker with a backlight printer, but will be lighter with an image light printer. Ta.

[0005] The inventors of the present invention have conducted intensive studies on the phenomenon that the print density changes over time depending on the shape of the recorded image even when the amount of toner supplied to the developing device is the same. We have investigated this and arrived at the present invention.

[0006] In backlight type printers,
Black pixels are formed by non-lit points. However, if the pixel region adjacent to this black pixel region is a lighting point (white pixel) region, the exposure potential of the lighting point will penetrate into the non-lighting point region of the black pixel region to some extent, as shown in FIG. Therefore, although toner should originally adhere to the entire black pixel area of the photoreceptor in FIG. 5A, the toner adhesion area becomes narrow as shown. So that the light emitting areas overlap each other,
Although this is due to the design, this is a necessary measure to prevent structural lines from occurring.

When forming the black pixels shown in FIGS. 6(a), (b), and (c), depending on whether the adjacent pixel area of each black pixel is a white pixel area or a black pixel area, A difference occurs in the amount of toner that adheres to the photoreceptor. That is, even if the number of black pixel dots is the same, if the black pixels are isolated points, the toner consumption amount is small, and if the black pixels are continuous points, the toner consumption amount is large. For example, in the example of FIG. 6, (a)<(b
There is a phenomenon in which the amount of toner consumed increases in the order of )<(c).

For example, even if a diagonal line of one dot and a horizontal or vertical line of one dot are black pixel areas with the same number of dots, the difference in the number of adjacent white pixel areas causes toner Consumption is different. Therefore, assuming that the amount of toner supplied to the developing device corresponds to the number of black pixels, the amount of toner consumed for diagonal lines is smaller than the amount of toner consumed for horizontal or vertical lines, so there is no toner in the developing device. is supplied in excess of what is required.

In the case of the image write method, the opposite phenomenon occurs. For example, when creating a crease line, if something that should originally be exposed as shown in (a) as shown in Figure 5(b) is exposed as shown in (a), then the joint between each black pixel area will be Portions with insufficient exposure potential are likely to occur. Then, a white image is formed in the underexposed portion, and when these are connected and formed, structural lines made of the white image may appear on the black image surface. To prevent this, the light is actually exposed as shown in (b). Therefore, even if the number of black pixel dots is the same, if the black pixels are isolated points, the amount of toner consumption will increase, but if the black pixels are continuous points, the amount of toner consumption will tend to decrease. For example, the amount of toner consumed to create one dot of diagonal lines is too large compared to the amount of toner consumed to create horizontal and vertical lines, so the amount of toner replenishment corresponds to the number of consecutive black pixels. , the amount of toner for diagonal lines is insufficient.
It was found that the line width of the diagonal lines gradually became thinner each time printing was performed.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a printer in which the print density does not change no matter what shape the recorded image is.

[0011]

[Means for Solving the Problems] By elucidating the cause of the instability of the line width described above, the above object of the present invention can be achieved by the following configuration.

That is, a latent image corresponding to the image data is formed on a photoreceptor in accordance with image data from a data input device, and an amount of toner corresponding to the latent image is supplied from a developing device to form a recorded image. A toner replenishment method for a printer replenishes a developing device with an amount of toner according to the amount of toner supplied, the ratio of the count number of image data and the edge count number at a change point where a white pixel changes to a black pixel. This toner replenishment method for a printer is characterized in that the toner replenishment amount to be replenished to a developing device is determined based on the calculated ratio.

[0013]

[Operation] The ratio between the image count number and the edge count number at the point of change from a white pixel to a black pixel corresponds to the amount of toner consumption, so calculate the amount of toner replenished to the developing device based on this ratio. . Therefore, regardless of the shape of the recorded image, a printed image with a constant density can always be obtained. With this method, whether the printer uses a backlight type exposure method or an image light type exposure method, an amount of toner suitable for each type can be supplied to the developing device.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described with reference to the drawings. A conceptual diagram of a printer implementing the method of the present invention is shown in FIG. An example of an image processing device to which the present invention is applied is a printer shown in FIG. As shown in FIG. 2, the printer of this embodiment is connected to a host computer or word processor (hereinafter sometimes referred to as a data input device or host) 21 and a printer control device (hereinafter sometimes referred to as ESS).
20, the image of the printer body (hereinafter referred to as base machine) 1, the output terminal (hereinafter referred to as IO
There is a thing called T. ) 4 to output image data.

As shown in FIG. 2, in the above printer, an information signal inputted as a print or an image from the data input device 21 is sent to a fluorescent display tube (not shown) of the IOT 4, and the information signal is sent to the fluorescent display tube. is used to write on the photosensitive drum 2, and after a series of processing is performed, it is transferred to paper. The outline of the main parts of the base machine 1 using this fluorescent display tube will be explained using FIG. 3.

A photosensitive drum 2 is disposed within the base machine 1 . In the figure, the photoreceptor 3 is the photoreceptor drum 2.
It is formed in layers on the outer peripheral surface. This photosensitive drum 2 is
It is connected to a drive device (not shown) so as to rotate in the direction of the arrow. On the outer periphery of the photosensitive drum 2, a charge corotron 5, a writing device 6 with a built-in fluorescent display tube, a condensing lens 7, a developing device 9, a transfer corotron 10, and a cleaning device 1 are arranged.
1 is placed.

In this image processing device, as the photosensitive drum 2 rotates in the direction of the arrow, the photosensitive member 3 is uniformly charged by the charge corotron 5, and then is irradiated with light from the writing device 6, and the electrostatic latent An image is formed. The condensing lens 7 is an arrangement of a large number of converging rod lenses in order to condense light emitted from a large number of light emitting elements constituting the writing device 6 onto the photoreceptor 3.

The photoreceptor 3 on which the electrostatic latent image has been formed is then developed by a developing device 9. The toner image formed on the photoreceptor 3 is transferred onto a sheet of paper by a transfer corotron 10, thermally fixed between a heat roll and a pressure roll (not shown), and then transported out. On the other hand, the photoreceptor 3 is cleaned by a cleaning device 11 and is reused.

Further, when this printer is used as a copying machine, the photoreceptor 3 on the charged surface of the photoreceptor drum 2 is exposed at an exposure point 13. Here, exposure point 13
A light image of a document (not shown) placed on a platen glass 12 placed on the top surface of the base machine 1 is incident on the base machine 1 . For this purpose, an exposure lamp 15,
A plurality of mirrors 16 and optical lenses 17 are arranged to transmit reflected light from the illuminated document surface, and predetermined ones of these are scanned to read the document.

FIG. 4 shows the circuit configuration of the ESS 20 of this embodiment. ESS20 is controlled by CPU68000. Information input from the data input device 21 is temporarily stored in the RAM 23A of the memory 23 in the ESS 20 via an interface 22 such as the Centro system, and a bit map of the page buffer memory 25 with a capacity of 1 Mbyte is stored from the RAM 23A in the memory 23. will be expanded to. The information of the page buffer memory 25 is transmitted to the video interface 26.
Video data 27 is sent to the IOT 4 via. When printing of the data in the page buffer memory 25 is completed, the next input data from the data input device 21 is transferred from the RAM 23A of the memory 23 to the page buffer memory 25. Also, based on the input information from the data input device 21, the ESS 20 connects the interface 2 such as RS232C.
9, the IOT4 is given a command to start printing, the output tray to be used, which bin of the output tray to output to, the paper size selection, etc. Receives information such as whether the paper is in print status or the number of bins in use on the print paper output tray.

Therefore, for example, if the IOT 4 is in the copying state, the ESS 20 outputs an output standby signal for the printer to the data input device 21 via the interface 22 such as the Centro system, and if it is in the printable state, the ESS 20 outputs an output standby signal for the printer to Data is transferred from the data input device 21 to the RAM 23A, and is expanded into a bitmap in the page buffer memory 25. After the expansion is completed, the data in the page buffer memory 25 is transferred to the IOT 4 according to the command 30, and a printing operation is performed. Ru.

[0022] Furthermore, ES is stored in ROM 23B of the memory 23.
A program for operating S20 and printer font information are stored. In addition, non-volatile memory (NVM) 2
3C is also connected, allowing necessary data to be saved even when the ESS20 is powered off.

[0023] The ESS 20 is provided with an IC card insertion slot (not shown), and when an IC card is set in this IC card insertion slot, the ID number of the IC card is used.
Information stored in the appropriate ROM in the C card is read out and output to the ESS 20 as print work information. Since the ESS has the above circuit configuration, the IOT4
The operation can be controlled.

The ESS 20 also includes an operation panel 39 similar to the console panel 8 of the base machine 1.
is provided. That is, in addition to keys for setting the number of sheets to be printed and magnification, the ESS 20 is also provided with keys for setting print density and the like.

Although not shown, the base machine 1 employs a distributed CPU architecture using serial communication centered around the main CPU. That is, in addition to the main CPU, the following CPUs are prepared and connected to the communication line. The main CPU also plays the role of supervising these CPUs.

That is, the sorter CPU is used to display various information in kanji on the liquid crystal display attached to the console panel 8 (FIG. 2) of the base machine 1, and to display an area for editing. CPU for display, CP for card when using IC card for specifying coordinates of original, etc.
A slave CPU and the like for an interface between the base machine 1 and the data input device 21 are connected.

[0027] Also, the RAM of the main CPU (not shown)
is connected to a battery for data backup, and is NVM-enabled so that necessary data can be saved even when the base machine 1 is powered off. In addition, the driver circuit (not shown) of the main CPU includes a well-known D
It is equipped with a /A (digital-to-analog) converter and a PWM (pulse width converter), and is connected to a high-voltage power supply (HVPS) (not shown), and is used to set the development bias of the developing device 9 shown in FIG. The amount of light emitted by the exposure lamp 15 is set, and the voltage value of the charge corotron 5 and the like is set.

Although not shown, the main CPU also controls the tray control section, sorter, paper size sensor, temperature sensor, light amount sensor, and the liquid crystal display section of the console panel.

A specific method of replenishing toner to the developing device in this printer having the above configuration will be described below. In the black image shown in FIG. 6, each line direction (writing device 6 (
6(a), (b), (
We focused on the differences in c). That is, Figure 6
The number of edge counts/number of image counts in (a), (b), and (c) are 1/1, 1/6, and 3/24, respectively.
It is.

Since the value of edge count/image count indicates the frequency with which black pixels are formed in adjacent areas of the image forming light source in the scanning direction, this value is approximately proportional to the amount of toner consumption. therefore,
Using the correction coefficient corresponding to the value of edge count number/image count number, calculate the amount of toner supplied to the developing device using the following formula (1).
Toner supply amount = K1 x (image count number) x K2 (1) However, K1 is a constant,
K2 is a correction coefficient determined by the value of edge count number/image count number. By calculating according to the following, it is possible to replenish the developing device with an amount of toner that is exactly proportional to the toner consumption amount.

Although the edge count number and the image count number are counted in the scanning direction, which is easy to measure, they may be counted in a direction perpendicular to the scanning direction. Furthermore, it is clear that the correction coefficient K2 calculated by counting in both directions is most faithful to the value to be corrected.

Here, the correction coefficient K2 is different depending on whether the printer is a backlight type printer or an image light type printer. In other words, in the backlight method, as shown in FIG. 6(a)
, (b), and (c), the value of the edge count number/image count number decreases in this order, but the toner consumption increases in proportion to this value, so the toner replenishment amount needs to increase in the above order. There is. Therefore, the correction coefficients in the backlight type printer exhibit the functional relationship shown in FIG. 7(a).

Furthermore, in the image write type printer, the toner consumption decreases in the order of FIG. 6(a) to FIG. 6(b) to FIG. 6(c), that is, as the edge count number/image count number decreases. Therefore, it is necessary to reduce the amount of toner replenishment. Therefore, in this case, a functional relationship between the edge count number/image count number and the correction coefficient K2 as shown in FIG. 7(b) is established.

The above-mentioned toner replenishment amount control method will hereinafter be referred to as image count/dispense control (ICDC).

However, if the toner supply amount is controlled only by ICDC, the following problems arise. That is, since the amount of toner supplied to the photoreceptor is not feedback-controlled, the density of the printed image is not stable. The cause of this is the developing device 9.
The amount of toner conveyed within the developing device 9 or the amount of toner supplied to the photoreceptor 3 (FIG. 3) may vary due to mechanical variations in (FIG. 3) or environments such as temperature and humidity. Therefore, even in the same exposure potential area on the photoreceptor 3, the reproduced density may differ. Therefore, by forming a patch-like toner image on the photoreceptor 3 on a trial basis (not shown), detecting the image density, feeding it back, and controlling the correction of the amount of toner replenishment, an image with stable density can be obtained. can get. The density of the patch image is determined using a patch density sensor 14 attached near the photoreceptor 3 via the transfer corotron 10 (FIG. 3). In this way, when creating a patch and correcting the toner supply amount, if you try to follow the toner density that changes according to the image data input from the host 21,
Patches need to be made frequently. As a result, ■ a burden is placed on the cleaning device 11 to remove the toner on the photoconductor 3 for patch production, ■ the inside of the base machine 1 becomes more contaminated with toner than necessary, and ■ the print speed decreases due to loss time due to this feedback control. There were problems such as

Specifically, as shown in FIG.
The amount of toner to be supplied (hereinafter sometimes referred to as the ADC calculation amount calculated by autodensity control (ADC)) is calculated in advance in accordance with the deviation from the target value of the toner density of the patch. Then, in accordance with the actually measured patch density, this ADC calculation amount is added to the ICDC calculation amount as shown in FIG. 9 to obtain the actual toner supply amount. The amount of toner replenishment in this case is as shown in the following equation (2). Toner supply amount = K1 x (image count number) x K
2+K3×(density deviation) (2) However, K1 and K2 are the same as in equation (1), and K3 is a constant.

Equation (2) in the previous section is the ADC calculation value image count number, that is, the toner consumption term is not corrected, so when there are large mechanical variations and images with a large amount of toner consumption, the toner density is not sufficient. may not be able to be maintained. In such cases. Determining the toner replenishment amount using the following equation (3) allows more accurate handling of variations in mechanical parts. Toner supply amount = K'1 x (image count number) x K2 x (density deviation)
+K3×(density deviation)
(3) However, K'
1 is a correction term corresponding to the deviation between the measured density of the recorded image and the target density, and K2 is the same as in equation (2). K3 is a constant.

Further, if an integral term is provided with a very small gain, the toner density maintenance property is further improved. Note that at this time, since there is a shortage of toner for patch creation in the developing device 9, an amount equivalent to this shortage may be added to the correction term in equations (2) and (3). Next, a case will be described in which each image data has a density level consisting of multiple gradations. Conventionally, the amount of toner replenishment for multi-tone data was based on a threshold value at a specific point, and the toner was replenished when that value was exceeded, so the amount of toner replenishment did not accurately correspond to the amount of toner consumption. It wasn't. Here, the specific point is, for example, a specific level such as 80H.

Therefore, the amount of toner replenishment can be accurately adjusted using the following method. For example, as shown in FIG.
For 8-bit data consisting of gradation data of 6 gradation levels, it is possible to count the video data of each bit for each video clock and calculate the amount of toner consumption according to the integrated value. There are three methods for calculating it: (i) A method of calculating toner consumption by simply integrating all 256 gradation values.

For example, as shown in FIG. 11, the development density of input data of 256 gradation levels has a substantially linear relationship corresponding to each gradation level. Therefore, the toner supply amount (=toner consumption amount) can be determined from the following equation (4). Toner supply amount=(unit toner consumption)×{Σ(gradation data)} (4) That is, the toner consumption amount is determined by multiplying the value obtained by adding all the gradation level data by the unit toner consumption amount. However, in this method, the counter circuit becomes complicated and it may not be possible to follow high-speed data, so the following method is more advantageous. (ii) This is a method in which the addition of 8-bit gradation data is counted in units of units and weighted addition is performed at the end to determine the amount of toner consumption. The weighted addition procedure is shown in FIG. The illustrated method is performed for each page of paper. By doing this, it is possible to follow even high-speed data. (iii) By using a frequency divider to count each part of (ii) above, the circuit configuration becomes somewhat complicated, but processing becomes faster. That is, a frequency divider is placed in front of each counter in FIG. 13, with the frequency division ratio increasing from the upper bits to the lower bits.

[0041] In the above method, the value of the image count number/edge count number is not considered;
Regarding multi-tone image data, the amount of toner replenishment can also be calculated by the same method as described above, taking into consideration the value of image count number/edge count number.

Next, the configurations of the image counter and edge counter will be explained below. First, the image counter will be explained. The image counter 32 can be easily calculated by ANDing the video clock and video data and counting up the result as shown in FIG. Note that since the amount of toner consumed per dot is small, a frequency divider may be installed before the counter.

Further, FIG. 14 shows an image counter for data in which each pixel data has density levels consisting of multiple gradations (hereinafter sometimes referred to as gradation data). The input of video data for each bit constituting a gradation is counted for each video clock. The edge counter 33 shown in FIG. 4 counts rising signals of video data (synonymous with image data). Furthermore, in the case of gradation data, there are the following three types of counting methods. (2) A method of counting the edge count value of the upper bit (for example, the 8th bit of video data). ■As shown in Figure 15, for example, the edge count value Q of the upper bit (for example, the 8th bit of video data) is
Compare the set value (for example, 7F in hexadecimal) D, and find that Q>D
If so, then the threshold counting method that outputs to the counter. ■As shown in Figure 16, two magnitude comparators have different set values H (for example, 7 in hexadecimal).
F), the set value L (for example, 40 in hexadecimal), and the edge count value Q of, for example, the upper bit (for example, data 7 of the 8th bit) are compared. A counting method with hysteresis that sets a flip-flop if Q>H and resets the flip-flop if Q<L to output to a counter.

Note that when the upper bit video data is counted by the edge counter in the method shown in FIG. Calculate the ratio of image counts. In this way, the image count number and the edge count number are measured, the value of edge count number/image count number is calculated, and the amount of toner replenishment is determined.

As explained above, the following embodiments of the present invention can be adopted. (A) Calculate the correction coefficient K2, which is determined according to the ratio of the image count number and the edge count number of the image data, and use the following formula (1) Toner supply amount = K1 x (image count number) x K2
(1) However, K1 is a constant. A printer toner replenishment method that determines the amount of toner replenished to the developing device. (B) A toner replenishment method for a printer that calculates the amount of toner replenishment to be supplied to a developing device by taking into account a correction value corresponding to a deviation between the actual measured density and target density of a recorded image using the toner replenishment method. (C) Following formula (2) Toner supply amount = K1 x (image count number) x K
2+K3×(density deviation) (2) However, K1 and K2 are the same as in equation (1), and K3 is a constant. The toner replenishment method for the printer described above, which calculates the amount of toner replenished to the developing device. (D) Following formula (3) Toner supply amount = K'1 x (image count number) x K2 (density deviation)
+K3×(density deviation)
(3) However, K'1
is a correction term corresponding to the deviation between the measured density of the recorded image and the target density, K2 is the same as in equation (2), and K3 is a constant. The toner replenishment method for the printer described above, which calculates the amount of toner replenished to the developing device. (E) forming a latent image corresponding to the image data on a photoreceptor in accordance with image data from a data input device, and supplying an amount of toner corresponding to the latent image from a developing device to form a recorded image; A toner replenishment method for a printer replenishes a developing device with an amount of toner according to the amount of toner supplied, and for image data having density levels consisting of multiple gradations, the following formula (4) Toner replenishment amount = (Unit toner consumption amount )×{Σ(gradation data)} (4) A printer toner replenishment method that calculates the amount of toner replenished to the developing device. (F) A toner replenishment method for the printer in which, for image data having multiple gradation density levels made up of a plurality of bits, the higher bits are weighted more heavily to obtain the image count number. (G) A toner replenishment method for the printer, in which the higher-order bits are weighted more heavily for image data having multiple gradation density levels composed of a plurality of bits to obtain an image count number and/or an edge count number. (H) In a printer that forms a latent image corresponding to the image data on a photoreceptor in accordance with image data from a data input device, and supplies an amount of toner corresponding to the latent image from a developing device to form a recorded image. , an image counter that counts the number of image data, an edge counter that counts the number of change points that change from white pixels to black pixels, a calculation means that calculates the ratio of the counts of both counters, and the calculation means toner replenishment amount calculation means for calculating the toner replenishment amount to be replenished to the developing device based on the calculated ratio;
A printer with (I) In the case of image data having multiple gradation density levels composed of a plurality of bits, the image counter and/or edge counter counts the number of image data and/or change points according to the upper bits.

As described above, the amount of toner to be replenished to the developing device is basically calculated using equation (1). At this time, the amount of toner to be replenished to the developing device is determined by formula (2), taking into account the actual measured density of the recorded image, the target density, and the correction value corresponding to the deviation.
, can be accurately determined using equation (3).

In the case of multi-gradation density level data, the resolution is generally high and the input level and toner consumption agree well. You can also calculate the supply amount. Further, at this time, the image data may be counted by weighting the image data of the upper bits which have a higher weight with respect to the amount of toner consumption. moreover,
In order to more accurately match the toner supply amount to the toner consumption amount, the value of image count number/edge count number may be considered. At this time, the image data of the upper bits having a higher weight with respect to the amount of toner consumption are weighted and counted.

[0048]

As described above, according to the present invention, the amount of toner to be replenished to the developing device is determined by taking into account the ratio between the image count number and the edge count number. Therefore, regardless of the shape of the recorded image, a printed image with a constant density can always be obtained. With this method, whether the printer uses a backlight type exposure method or an image light type exposure method, an amount of toner suitable for each type can be supplied to the developing device.

In addition, even in the case of multi-tone image data, it is possible to calculate an accurate amount of toner replenishment by taking into account the ratio of the image count number and the edge count number, but it is possible to calculate the accurate amount of toner replenishment by taking into account the ratio of the image count number and the edge count number. It is also possible to replenish just the right amount of toner by adjusting the toner replenishment amount according to the integrated value.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of a printer for implementing the method of the present invention.

FIG. 2 is a schematic configuration diagram of a printer according to an embodiment of the present invention.

FIG. 3 is a sectional view of main parts of the base machine (IOT) according to the embodiment of the present invention.

FIG. 4: Printer control device (ESS) according to an embodiment of the present invention
FIG.

FIG. 5 is a diagram showing the amount of light emitted on a photoreceptor depending on an exposure method.

FIG. 6 is an image forming diagram.

[Fig. 7] Correction coefficient K2 according to the exposure method of the embodiment of the present invention
It is a calculation diagram of

FIG. 8 is a diagram for calculating the ADC calculation amount for patch density according to the embodiment of the present invention.

FIG. 9 is a diagram showing the amount of toner replenishment by ICDC+ADC according to the embodiment of the present invention.

FIG. 10: AD versus ADC calculation amount in the embodiment of the present invention
It is a calculation diagram of a C correction coefficient.

FIG. 11 is a diagram showing the relationship between multi-tone image data and toner consumption according to an embodiment of the present invention.

FIG. 12 is a flowchart showing a procedure for calculating toner supply amount by weighted addition of multi-tone image data according to an embodiment of the present invention.

FIG. 13 is a counter for weighted addition of multi-tone image data according to an embodiment of the present invention.

FIG. 14 is a partial configuration diagram of the present printer having a multi-tone image data counter according to an embodiment of the present invention.

FIG. 15 is a configuration diagram showing an example of a multi-gradation image data counter according to an embodiment of the present invention.

FIG. 16 is a configuration diagram showing an example of a multi-gradation image data counter according to an embodiment of the present invention.

[Explanation of symbols]

1　　　Printer body 4 IOT 14 Patch concentration sensor 20 Printer control device (ESS) 21 Data input device (host) 23 Memory 32 Image counter 33 Edge counter

Claims (1)

[Claims] Claim 1: A latent image corresponding to the image data is formed on a photoreceptor in accordance with image data from a data input device, and an amount of toner corresponding to the latent image is supplied from a developing device to form a recorded image. A toner replenishment method for a printer replenishes a developing device with an amount of toner according to the amount of toner supplied, the ratio of the count number of image data and the edge count number at a change point where a white pixel changes to a black pixel. A toner replenishment method for a printer, characterized in that the amount of toner replenishment to be replenished to a developing device is determined based on the calculated ratio.