JPH0772730A - Image recorder - Google Patents

Abstract

PURPOSE:To economically exchange a toner cartridge by precisely displaying the exchanging time of the toner cartridge even when the residual quantity of toner in the toner cartridge becomes equal to or under the detecting ability of a toner sensor. CONSTITUTION:When the residual quantity of the toner in the toner cartridge 1 is equal to or over the prescribed quantity, the existence of the toner is decided based on the detection of the toner sensor 2(201). When the residual quantity of the toner becomes equal to or under the prescribed quantity, the existence of the toner is indirectly decided based on the number of recorded sheets or the like (202). Based on this decision, the exchanging time of the cartridge 1 is displayed. Thus, even when the residual quantity of the toner becomes equal to or under the detecting ability of the sensor 2, the exchanging time of the cartridge 1 is precisely displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention develops a recording latent image exposed on an electrostatic photosensitive member by a laser beam or the like with toner supplied from a cartridge, and transfers and fixes the developed toner image on a recording paper. The present invention relates to an electrophotographic image recording device.

[0002]

2. Description of the Related Art In an electrophotographic image recording apparatus that uses toner supplied from a cartridge, the toner is replenished by replacing the cartridge. The toner remaining amount in the cartridge is determined in order to determine the replacement time of the cartridge. Sensing is performed.

In a conventional device of this type, as shown in FIG. 8, a toner sensor 2 for detecting the amount of toner in a cartridge and a residual toner amount of 22 or more as a reference value based on the detection output of the toner sensor 2. The display unit 26 includes a determination unit 201 that determines whether there is a toner, a recording control unit 24, and a display unit 26, and when the determination unit 201 determines that there is no toner based on the detection output of the sensor 2. The time to replace the cartridge has been displayed (see, for example, Japanese Patent Application Laid-Open No. 3-197872).

[0004]

However, according to such a configuration, it is not possible to accurately display the replacement time of the toner cartridge, and the cartridge is replaced even though the remaining toner amount is still sufficient. There was a problem that an economy would arise.

The above problem occurs for the following reasons. That is, there is a limit to the remaining amount of toner that can be measured by the toner sensor, and toner below a certain amount cannot be effectively measured. For this reason, in the conventional device, even if a sufficient amount of toner that can be used for recording still remains, when the remaining amount falls below a certain amount, how much toner actually remains at a toner amount less than that, In other words, it was not possible to accurately display the number of records that could be recorded in the future.

Therefore, in the past, the display of the replacement time of the toner cartridge indicates that the toner remaining amount may be exhausted, not whether the toner remaining amount is actually available or not. There is no choice but to display the toner remaining amount within a range where the remaining toner amount is effectively measured, that is, the toner cartridge replacement time based on the detection capability of the toner sensor.

As a result, even though the amount of toner has decreased, it is uneconomical that the toner cartridge is replaced when the remaining amount falls below the detection capability of the toner sensor. Was occurring.

The present invention has been made in view of the above-mentioned problems. Even when the amount of toner remaining in the cartridge is less than the detection capability of the toner sensor, the toner cartridge replacement time is accurately displayed, and the toner is replaced. It is an object of the present invention to provide an image recording device that can economically replace a cartridge.

[0009]

In order to solve the above-mentioned problems, the present invention determines the presence / absence of toner based on the detection of a toner sensor when the amount of toner remaining in a cartridge is equal to or more than a prescribed value, and determines the amount of toner remaining. When the value becomes less than the specified value, the presence or absence of toner is indirectly determined based on the number of recorded sheets, and the replacement time of the toner cartridge is displayed based on this determination.

[0010]

According to the present invention, since the toner cartridge replacement time can be accurately displayed even when the remaining toner amount becomes less than the detection capacity of the toner sensor, the present invention makes it possible to replace the toner cartridge economically. Can be performed by

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

In the figures, the same reference numerals indicate the same or corresponding parts. FIG. 1 is a block diagram showing a schematic configuration of an image recording apparatus according to an embodiment of the present invention. Reference numeral 1 is a toner cartridge, 2 is a toner sensor for detecting the amount of toner remaining in the toner cartridge 1, and 3 is a toner sensor.
Reference numeral 201 is a toner box in the toner cartridge 2, 201 is a first determining means for determining the presence / absence of toner based on the detection output of the toner sensor 2, and 202 is a second means for indirectly determining the presence / absence of toner based on the number of recorded sheets. 2 determination means, 2
4 is a general-purpose data processing device having a microcircuit, a so-called microcomputer for controlling the entire image recording device, a recording control unit 26 is a display unit for displaying the replacement time of the toner cartridge 1, 30 is an image data processing unit, and 8 is a laser. A laser-scanning unit (LSU) that performs image exposure by scanning light.

FIG. 2 is an abbreviated sectional view showing the schematic structure of the above-mentioned image recording apparatus, in which 1 is a toner cartridge and 2 is a toner cartridge.
Is a toner sensor, 3 is a toner box in which toner is stored, 4 is a stirring member that stirs the toner in the toner box 3, and 5 is rotated together with the stirring member 4 to periodically detect the detection surface of the toner sensor 2 (t1). Cleaning brush for wiping and cleaning, 6 is a magnet roller, 7 is an electrostatic photoconductor, 8 is a laser scanning unit (LSU) for exposing the electrostatic photoconductor 7 to an image, 9 is a charging unit, 10 is a waste toner box 1
Reference numeral 1 is a recording paper, 12 is a registration roller for feeding the recording paper 11 to a recording position, 13 is a transfer device for transferring the toner image formed on the photoconductor 7 onto the recording paper 11, and 14 is toner transferred onto the recording paper 11. A fixing roller that fixes an image.

FIGS. 3 and 4 show the output waveform of the toner sensor 2 and the toner level in the toner box 3. The output waveform of the toner sensor 2 changes from (a) to ((a) as the toner is consumed. D) The state gradually changes.

That is, for the detection output of the toner sensor 1, the cleaning cycle of the sensor detection surface by the cleaning brush 5 is 1
At the cycle (t1), the H level and the L level alternately appear, but the H level period is long while the toner remaining amount is large, and the H level period is short and the L level period is long as the toner remaining amount is small. Then, when the toner runs out, only the L level is output. That is, the toner sensor 2 outputs the remaining amount of toner in the toner cartridge 1 at a ratio between the H level period and the L level period of the output voltage, a so-called duty ratio.

Here, as shown in FIG. 1, the first judging means 201 includes a sampling circuit 21 for counting the remaining amount of toner by counting the L level period (or H level period) of the toner sensor 1. The comparison circuit 23, which compares the remaining amount of toner measured by the sampling circuit 21 with a constant reference value 22, determines whether the remaining amount of toner in the toner cartridge 1 is equal to or less than a specified amount.

At this time, the reference value 22 is set to be the minimum amount of toner that can accurately measure the amount of remaining toner based on the output of the toner sensor 1, that is, the so-called minimum detected amount of toner.

As shown in FIG. 3, the cleaning brush 5 is used to measure the remaining amount of toner by the detection output of the toner sensor 1.
The cleaning cycle by 1 is set as one measurement cycle (t1), and the toner sensor is synchronized with the sampling pulse having a cycle (t2) sufficiently shorter than the one measurement cycle (t1) during the one measurement cycle (t1). The measurement operation is repeated a predetermined number of times (n times: n> 1), and the total of the L level periods accumulated by the predetermined number of measurement operations. The numerical value is compared with the reference value 22 as the measured value of the remaining amount of toner. As a result, the accuracy of measurement of the remaining toner amount is improved and the counting error due to noise or the like is reduced.

The second judging means 202 is provided with the above reference value 22.
Using a number counter (or register) 25 in which the number of printable sheets (for example, 100 sheets) is preset as an initial value depending on the remaining toner amount, the number of printable sheets preset in this counter 25 is The subsequent recordable number is calculated by subtracting the number of recordable sheets, etc., and the recordable sheet number thus calculated is replaced with the remaining toner amount by the first determining means 201, and is sent to the recording control unit 24. hand over. Sheet counter 25
The power is backed up so that it retains its contents even when the power is turned off.

The image data processing unit 30 includes a page memory 31 for temporarily storing input image data, a black ratio counter 32 for counting the ratio of black pixels of the image data input to the page memory 31, that is, a black ratio, and a page. A serial conversion unit 33 that serially outputs the image data read out from the memory 31 for recording in the scanning order, a timing control unit 34 that controls the output timing of the image data, and the like.

The black ratio counted by the black ratio counter 32 is transferred to the recording control unit 24, and the recordable number calculated by the above-mentioned second judging means 202 is corrected, and the laser scanning unit 8 described later. It is used for variable control of laser power (amount of emitted light).

The laser scanning unit 8 includes a semiconductor laser unit 35 as an exposure light source and an image data processing section 3.
The laser driver 36 for brightness-modulating the light emission of the semiconductor laser unit 35, the light emission amount variable circuit 37, and the light emission output level of the semiconductor laser unit 35, that is, the laser power are monitored by image data output serially from 0 in the scanning order. It is composed of a laser monitor circuit 38 and the like.

The light emission amount variable circuit 37 controls the light emission output level of the semiconductor laser unit 35, that is, the laser power by the output of the laser monitor 38 in a negative feedback manner, and variably adjusts the laser power under the control of the recording controller 24. To do.

The variable adjustment of the laser power is performed when controlling the toner consumption amount. FIG. 5 shows the relationship between the laser power and the toner consumption amount, and the toner consumption amount tends to increase with the laser power.
Therefore, the toner consumption can be controlled by adjusting the laser power.

The operation of the image recording apparatus configured as described above will be described below. FIG. 6 is a flow chart showing the schematic operation of the main part of the image recording apparatus described above. To be described with reference to FIGS. 1 to 5, first, by turning on the power to start the apparatus, After various initialization operations (not shown), the first determination unit 201 measures the toner remaining amount based on the detection output of the toner sensor 2 (S11).

Here, if the remaining amount of toner that is determined by the reference value 22 and is equal to or more than the specified amount is measured, then 10 will be described later.
It is checked whether the 0-sheet mode is set (S
12).

If the 100-sheet mode is not set,
The recording operation in the normal mode is performed under the control of the remaining toner amount based on the output of the toner sensor 2 (S13).

In the recording operation in the normal mode, the remaining toner amount based on the detection output of the toner sensor 2 is monitored for each recording. As described above, the monitor of the remaining toner amount at this time is always counted at the latest n measurement cycles, with the cleaning cycle (t1) of the detection surface of the toner sensor 2 by the cleaning brush 5 as one measurement cycle. This is performed by comparing the total count value of the L level period with the reference value 22.

The reference value 22 is set to a value corresponding to the amount of toner capable of accurately measuring the remaining amount of toner based on the output of the toner sensor 2 and recording 100 sheets.
For example, if the amount of toner required for recording one sheet is 70 mg, a value corresponding to a toner amount of 7 g for 100 sheets is set as the reference value 22. In this case, the remaining toner amount of 7 g is also an amount accurately measured based on the toner sensor 2.

When the toner is consumed by the recording operation in the normal mode described above and the remaining amount of the toner is reduced to the prescribed amount determined by the reference value 22, 100 which will be described below.
Switch to single-sheet mode.

In the 100-sheet mode, it is first checked whether the 100-sheet mode has already been set (S2).
1).

If the 100-sheet mode is not set,
The number of sheets that can be recorded by the specified amount of toner (7 g) is 1
00 sheets are preset in the sheet number counter 25 (S2
2).

After that, the recording operation is performed under the control of the recordable sheet number given by the count value of the sheet number counter 25 instead of the toner remaining amount actually measured by the toner sensor 2 (S24).

In the recording operation in the 100-sheet mode,
The details will be described later, but the number counter 25
The count value of is decremented. Specifically, the count value is decremented by 1 for each recording. As a result, the recordable number of sheets is given by the count value of the sheet number counter 25.

The count value of the sheet number counter 25 is checked every time one sheet is printed (S25).

Here, when 100 sheets are printed and the count value becomes 0, it is indirectly determined that the remaining toner amount is completely exhausted at this point, and one blank sheet is output based on this determination. The user is made aware that the toner is exhausted, and the subsequent recording operation is prohibited, and the display unit 2
A display for instructing the replacement of the toner cartridge 1 is given from 6.

As a result, the user can know when to replace the toner cartridge 1.

FIG. 7 shows the details of the recording operation (S24) in the 100-sheet mode. First, the black ratio of the image data to be recorded is the first reference ratio (10%) or more. It is determined whether or not (S241, 242).

When the black ratio is less than the first reference ratio (10%), the power of the laser for exposure scanning of the image is set to the normal level (Po in FIG. 5) and the exposure scanning of the image is performed.
However, if the black ratio is greater than or equal to the first reference ratio (10%),
Laser power level lower than usual (P1 in Fig. 5)
Exposure scanning of the image is performed (S242, 24
3).

As described above, recording is performed while adjusting the laser power according to the black ratio of the image,
It is possible to correct the variation in the toner consumption amount depending on the magnitude of the black ratio and maintain the accuracy of the recordable number given by the count value of the number counter 25.

When recording of one sheet is completed, the count value of the sheet number counter 25 is decremented by 1 (S245).

Thereafter, it is judged whether or not the black ratio of the recorded image is equal to or higher than the second reference ratio (20%) (S24).
6).

When the black ratio is less than the second reference value (20%), the variation of the toner consumption amount is corrected only by adjusting the laser power, so that the count value is not corrected and one sheet is corrected. The recording operation and the subtraction process of the counter 25 can be ended.

However, when the black ratio is equal to or higher than the second reference ratio (20%), the toner consumption amount per recording sheet is too large to be corrected only by adjusting the laser power. A process of further subtracting a predetermined correction number from the value is performed (S247).

As described above, even if the variation in the black ratio cannot be corrected only by adjusting the laser power, the variation can be corrected by the count value of the sheet number counter 25.

As a result, the accuracy of the number of printable sheets given by the count value of the counter 25 is further enhanced, and it is possible to prevent the recording from becoming impossible due to the toner being exhausted before the count value of the counter 25 becomes zero. it can.

As described above, in the recording operation in the 100-sheet mode, the remaining toner amount in the toner cartridge 1 is fully used for recording without relying on the measurement of the remaining toner amount by the toner sensor 2. In addition, it is possible to notify the user of the replacement time of the cartridge 1 accurately.

After this, the user selects the toner cartridge 1
6 is replaced with a new one, as shown in FIG. 6, the 100-sheet mode is automatically canceled, and the recording operation in the normal mode is performed while the remaining toner amount decreases again to the specified amount (S13). , 14).

If the setting state of the 100-sheet mode is registered in the storage means backed up by the power source,
Even if the operation of the apparatus is terminated before recording 100 sheets, the operation can be restarted from the previous state and used again when the operation of the apparatus is restarted.

As described above, even when the remaining amount of toner falls below the detection capability of the toner sensor, the time to replace the toner cartridge can be displayed accurately, so that the toner cartridge can be replaced economically. Is possible.

The 100-sheet mode may be, for example, a 50-sheet mode or a 200-sheet mode, depending on the detection ability of the toner sensor 2.

Also. First and second judging means 201, 20
2 and the counter 25 may be incorporated in the recording control unit 24 as software.

[0053]

As is apparent from the above description, according to the present invention, when the toner remaining amount in the cartridge is more than the specified value,
The presence / absence of toner is determined based on the detection of the toner sensor, and if the remaining amount of toner is less than the specified amount, the presence / absence of toner is indirectly determined based on the number of recorded sheets, and based on this determination, the toner cartridge By displaying the replacement time, it is possible to accurately display the replacement time of the toner cartridge even if the remaining amount of toner falls below the detection capacity of the toner sensor, so that the toner cartridge can be replaced economically. It has the effect of being able to.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an image recording apparatus according to an embodiment of the present invention.

FIG. 2 is an abbreviated sectional view showing a schematic structure of an image recording apparatus according to the present invention.

FIG. 3 is a diagram showing the output waveform of the toner sensor for each remaining amount of toner.

FIG. 4 is a diagram showing toner levels in a toner box according to a remaining amount of toner.

FIG. 5 is a diagram showing the relationship between laser power and toner consumption.

FIG. 6 is a flowchart showing a schematic operation of a main part of the image recording apparatus according to the present invention.

FIG. 7 is a flowchart showing a part of FIG. 6 in detail.

FIG. 8 is a schematic configuration diagram of a conventional image recording apparatus.

[Explanation of symbols]

 1 Toner Cartridge 2 Toner Sensor 3 Toner Box 201 First Judging Means 202 Second Judging Means 24 Recording Control Section 26 Display Section 30 Image Data Processing Section 4 Stirring Member 5 Cleaning Brush 6 Magnet Roller 7 Electrostatic Photosensitive Body 8 Laser Scan Unit (LSU) 9 Charging unit 10 Waste toner box 11 Recording paper 12 Registration roller 13 Transfer device 14 Fixing roller 21 Sampling circuit 22 Reference value 23 Comparison circuit 30 Image data processing unit 31 Page memory 32 Black ratio counter 33 Serial conversion unit 34 Timing Control unit 35 Semiconductor laser unit 36 Laser driver 37 Emission amount variable circuit 38 Laser monitor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location G03G 15/04 15/043 15/08 112 (72) Inventor Tadaaki Ohno 1006 Kadoma, Kadoma, Osaka Prefecture Address: Matsushita Electric Industrial Co., Ltd. (72) Inventor: Takahiro Kikuchi 2-3-8 Shimomeguro, Meguro-ku, Tokyo Matsushita Electric Transmission Co., Ltd. (72) Inventor Kiyoshi Futaki, 2-3, Shimomeguro, Meguro-ku, Tokyo No. 8 Matsushita Dentsu Co., Ltd. (72) Inventor Koichi Nagoshi 2-3-3 Shimomeguro, Meguro-ku, Tokyo Matsushita Dentsu Co., Ltd. (72) Inventor Tomoyasu Kamada 1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial (72) Inventor Shuji Nishina 1014 Miyahara-cho, Kofu-shi, Yamanashi Yamanashi Electronics Industrial Co., Ltd. (72) Inventor Jiro Fukasawa 1014 Miyahara-cho, Kofu-shi, Yamanashi Yamanashi Electronics Inside the stock company (72) Inventor Shinji Tsuji 1014 Miyahara-cho, Kofu City, Yamanashi Prefecture Yamanashi Electronics Co., Ltd.

Claims (3)

[Claims] 1. An electrophotographic image recording apparatus for recording an image using toner supplied from a cartridge, wherein a first judgment is made on the basis of the detection of a toner sensor for the presence / absence of toner in the cartridge. Means, second judging means for judging the presence / absence of toner on the basis of the number of recorded sheets, and the second judging means when the remaining amount of toner measured based on the toner sensor is equal to or less than a specified amount. An image recording apparatus, comprising: a control unit that determines the presence or absence of toner, and displays a toner cartridge replacement time based on the determination. 2. An electrophotographic image recording apparatus for recording an image using toner supplied from a cartridge, comprising: a toner sensor for detecting toner in the cartridge; and a detection output of the toner sensor a predetermined number of times. First determining means for determining the remaining toner amount by sampling and measuring the remaining toner amount in the cartridge from the total value and comparing the measured value with a reference value; And a second determination unit that determines the presence / absence of toner based on a count value subtracted from a predetermined preset value according to the number of recording sheets. 3. An electrophotographic image recording apparatus for recording an image using toner supplied from a cartridge, wherein a first judgment is made on the basis of detection of a toner sensor to detect the presence or absence of toner in the cartridge. And a second value for determining the presence / absence of toner based on a count value subtracted from a predetermined preset value according to the number of recording sheets when the remaining amount of toner measured based on the toner sensor is equal to or less than a specified amount. The determination means and the control means for lowering the power level of the laser for exposing the image having the black ratio higher than the reference to the normal level when the presence / absence of the toner is determined by the second determination means. Image recording device.