JP2003270963A - Image forming apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the intermediate condition of the progress of waste toner storage amount in a waste toner container. <P>SOLUTION: The number of writing pixels of writing pixel data transmitted to a laser beam source 51 so as to form a toner image on a photoreceptor is counted by a dot counter 118. The counted number of pixels is integrated by a CPU 111 and the integrated value is stored in the specified area of a RAM 113. The CPU 111 decides the waste toner storage amount in the waste toner container based on the integrated value. The decided waste toner storage amount is displayed on an operation display panel 8 by the CPU 111. When a waste toner fullness sensor 83 detects the waste toner storage amount showing the fullness, such an effect is displayed on the panel 8 by the CPU 111. <P>COPYRIGHT: (C)2003,JPO

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 technique for printers, copiers, facsimile machines and the like.

[0002]

2. Description of the Related Art Conventionally, a charged photoconductor is exposed by an exposing means to form an electrostatic latent image on the photoconductor, and toner is attached to the electrostatic latent image by developing means to form a toner image. An electrophotographic image forming apparatus is known in which a toner image is formed and transferred to a transfer paper to obtain a predetermined image, and in particular, as an apparatus that enables formation of a color image,
An image forming apparatus is known in which a toner image formed on a photoconductor is primarily transferred to an intermediate transfer medium, and the toner image transferred to the intermediate transfer medium is secondarily transferred to a transfer paper.

In this image forming apparatus, when a color image is formed, for example, toner images of a plurality of colors are sequentially formed on a photosensitive member, and primary transfer is performed on an intermediate transfer medium for each toner image of each color. A color toner image is formed by superimposing toner images of a plurality of colors on an intermediate transfer medium, and the color toner image is secondarily transferred onto a transfer paper to obtain a color image.

Since the secondary transfer efficiency from the intermediate transfer medium to the transfer paper is generally not 100%, the toner remains on the intermediate transfer medium after the secondary transfer is completed. Therefore, the conventional image forming apparatus includes a cleaning unit that removes the residual toner and a waste toner container that stores the residual toner removed by the cleaning unit as waste toner, and the amount of waste toner stored in the waste toner container is full. In many cases, a waste toner storage amount sensor, such as an optical sensor, is provided for detecting that the toner has reached the limit.

[0005]

However, if only the above-mentioned waste toner storage amount sensor is provided, the progress of the waste toner storage amount cannot be notified, and the full storage is suddenly detected, so that the apparatus is easy to use. Not a thing.

The present invention has been made in view of the above,
An object of the present invention is to provide an image forming apparatus and method capable of detecting the progress of the amount of waste toner stored in a waste toner container.

[0007]

In order to achieve the above object, the invention according to claim 1 is an intermediate transfer medium to which a toner image formed on a photosensitive member is primarily transferred, and an intermediate transfer medium of the intermediate transfer medium. In an image forming apparatus including a secondary transfer unit that secondarily transfers a toner image onto a transfer sheet, a cleaning unit that removes toner remaining on the intermediate transfer medium after the secondary transfer, and the intermediate transfer by the cleaning unit. A waste toner container that stores the waste toner removed from the medium, a dot counting unit that counts the number of pixels forming the toner image, and the number of pixels counted by the dot counting unit are integrated, and the integrated value is obtained. And a storage amount determination means for determining the storage amount of the waste toner in the waste toner container.

According to this structure, the toner image formed on the photoconductor is primarily transferred to the intermediate transfer medium, the toner image of the intermediate transfer medium is secondarily transferred to the transfer paper, and the intermediate transfer is performed after the secondary transfer. The toner remaining on the medium is removed, and the removed waste toner is stored in a waste toner container, while the number of pixels forming a toner image is counted, the counted number of pixels is integrated, and the integrated value is added. Based on this, the amount of waste toner contained in the waste toner container is determined. Since the residual toner on the intermediate transfer medium is almost proportional to the toner usage amount, the waste toner storage amount can be accurately determined by using the integrated value of the number of pixels which is a value corresponding to the toner usage amount. It will be.

Further, if the waste toner container is provided with an identification means and a container discrimination means for discriminating the waste toner container based on the identification means (claim 2), for example, an individual waste toner container is provided. Since it is possible to identify the waste toner container and determine whether or not the waste toner container is new, erroneous determination of the waste toner storage amount is prevented.

Further, a container attachment / detachment detecting means for detecting attachment / detachment of the waste toner container to / from the apparatus main body is further provided, and the container discriminating means detects the attachment / detachment of the waste toner container to the apparatus main body by the container attachment / detachment detection means. When the waste toner container is detected, it is determined whether or not the waste toner container is new based on the identification means.The storage amount determination means determines that the waste toner container is new by the container determination means. In this case, the integrated value may be reset to 0, and when it is determined that the product is not new, the integrated value may be reset without being reset to 0 (claim 3).

According to this structure, when it is detected that the waste toner container is attached to the apparatus main body, it is determined whether or not the waste toner container is new, and when it is determined that the waste toner container is new. When the integrated value of the number of pixels is reset to 0 and it is determined that the waste toner container is not a new product, the integrated value is not reset to 0 and the integration is continued, so that the waste toner container is replaced with a new one. In any case where the toner is used as it is without being replaced with a new one, erroneous determination of the waste toner storage amount can be prevented.

Further, the invention according to claim 4 is for fullness detection means for detecting whether or not the amount of waste toner accommodated in the waste toner container is full, and for notifying a user of a predetermined notification content. When the waste toner storage amount determined by the notification unit and the storage amount determination unit reaches a preset predetermined value close to the full detected by the full detection unit, the fact is used by the notification unit. And a notification control means for notifying the person.

According to this structure, by detecting whether or not the amount of waste toner stored in the waste toner container is full,
A situation in which the waste toner overflows into the waste toner container is reliably prevented. Further, when the waste toner storage amount reaches a preset predetermined value which is close to being full, the user is notified of that fact, so that the waste toner storage amount is suddenly filled while the apparatus is in use. The detected inconvenience is eliminated, and a new waste toner container for replacement can be prepared in advance, which improves the usability of the apparatus.

The invention according to claim 5 is a display control for displaying a predetermined display content, and a display control for displaying the waste toner storage amount determined by the storage amount determination means on the display means. And means are further provided.

According to this structure, since the waste toner storage amount is displayed on the display means, the inconvenience that the waste toner storage amount suddenly becomes full during use of the apparatus is eliminated, and the waste toner storage amount can be replaced in advance. It is possible to improve the usability of the device, such as preparing a new waste toner container.

According to a sixth aspect of the present invention, a toner image is formed on a photoconductor, the toner image on the photoconductor is primarily transferred onto an intermediate transfer medium, and the toner image on the intermediate transfer medium is transferred onto a transfer paper. A dot counting step of counting the number of pixels forming the toner image in an image forming method in which secondary transfer is performed and toner remaining on the intermediate transfer medium after the secondary transfer is removed; The amount of waste toner stored in the waste toner container that stores the waste toner removed from
And a storage amount determination step of making a determination based on an integrated value obtained by integrating the number of pixels counted in the dot counting step.

According to this structure, the toner image formed on the photoconductor is primarily transferred to the intermediate transfer medium, the toner image of the intermediate transfer medium is secondarily transferred to the transfer paper, and after the secondary transfer, the intermediate transfer is performed. The toner remaining on the medium is removed, and the removed waste toner is stored in a waste toner container, while the number of pixels forming a toner image is counted, the counted number of pixels is integrated, and the integrated value is added. Based on this, the amount of waste toner contained in the waste toner container is determined. Since the residual toner on the intermediate transfer medium is almost proportional to the toner usage amount, the waste toner storage amount can be accurately determined by using the integrated value of the number of pixels which is a value corresponding to the toner usage amount. It will be.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the configuration of a printer which is an embodiment of an image forming apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an internal configuration of the printer, FIG. 2 is a block diagram showing an electrical configuration of the printer, and FIG. 3 is a development view of an intermediate transfer belt.

This printer superimposes four color toners of yellow (Y), magenta (M), cyan (C), and black (K) to form a full-color image, for example, only black (K) toner. Is used to form a monochrome image. In this printer, when a print command signal including an image signal is given to the main control unit 100 from an external device (for example, a personal computer, PC in this embodiment) 200 such as a host computer, the main control unit 100
The engine control unit 110 controls each unit of the engine unit 1 in response to a control signal from the control unit 110 to respond to the image signal on the transfer sheet 4 conveyed from the sheet feeding cassette 3 disposed below the apparatus main body 2. Print the image.

The engine unit 1 includes the photoconductor unit 1
0, a rotary developing unit 20, an intermediate transfer unit 30, a fixing unit 40, and an exposure unit 50. The photoconductor unit 10 includes a photoconductor 11, a charging unit 12, and a cleaning unit 13, and the rotary developing unit 20 includes
Yellow developing unit 2 containing yellow toner
Y, magenta developing unit 2M containing magenta toner, cyan developing unit 2 containing cyan toner
C, a black developing unit 2K containing black toner, and the like. The intermediate transfer unit 30 includes an intermediate transfer belt 31, a vertical synchronization sensor 32, a belt cleaner 33,
A gate roller pair 34, a secondary transfer roller 35, a photoconductor driving motor 36, and the like are provided. Above 7 units 1
Each of 0, 2Y, 2M, 2C, 2K, 30, and 40 is configured to be detachable from the apparatus body 2.

The photoconductor 11 of the photoconductor unit 10 includes the seven units 10, 2Y, 2M, 2C, 2K, 30,
In a state in which 40 is attached to the apparatus main body 2, it rotates in the direction of arrow 5 by the photoconductor driving motor 36, and is in contact with the intermediate transfer belt 31, and this contact position is in the primary transfer portion 14. It is set. Around the photoconductor 11, along the rotation direction 5, a charging unit 12, a rotary developing unit 20, and a cleaning unit 13 are arranged.

The charging section 12 is provided with a wire electrode to which a high voltage of a predetermined level is applied, and uniformly charges the outer peripheral surface of the photoconductor 11 by, for example, corona discharge. The cleaning unit 13 is arranged immediately upstream of the charging unit 12 in the rotation direction 5 of the photoconductor 11 and downstream of the primary transfer unit 14, and the primary of the toner image from the photoconductor 11 to the intermediate transfer belt 31. The toner remaining on the outer peripheral surface of the photoconductor 11 after the transfer is scraped off by the cleaning blade 15 to clean the surface of the photoconductor 11. The residual toner on the photoconductor 11 scraped off by the cleaning blade 15 is stored in the waste toner container 16 as waste toner.

The exposure unit 50 is reflected by a laser light source 51 formed of, for example, a semiconductor laser, a polygon mirror 52 that reflects the laser light from the laser light source 51, a polygon motor 53 that rotationally drives the polygon mirror 52, and a polygon mirror 52. Lens unit 5 for focusing the laser light
4, a plurality of reflection mirrors 55, a horizontal synchronization sensor 56, etc. are provided. Is reflected by the polygon mirror 52,
The laser beam 57 emitted through the lens unit 54 and the reflection mirror 55 scans the surface of the photoconductor 11 in the main scanning direction (direction perpendicular to the paper surface of FIG. 1), and the static light corresponding to the image signal is obtained. An electrostatic latent image is formed on the surface of the photoconductor 11.
At this time, the horizontal synchronization sensor 56 obtains a synchronization signal in the main scanning direction, that is, a horizontal synchronization signal.

The polygon motor 53 is a polygon mirror 5.
2 is a preset rotation speed, for example 30,000 rp
It is driven to rotate at a high speed of m (revolutions / minute). For example, it has a configuration capable of high-speed rotation by an oil bearing, and when the rotation speed reaches the above-mentioned set rotation speed by starting the drive, the CPU
A ready signal is sent to 111. The exposure unit 50 is
It has a function as an exposure unit.

The rotary developing section 20 adheres the toner of each color to the electrostatic latent image and develops it. The yellow developing unit 2Y, the magenta developing unit 2M, the cyan developing unit 2C, and the black developing unit 2K of the rotary developing unit 20 are rotatably provided around the axis, and these developing units 2Y, 2M, 2C and 2K are predetermined. It is movably arranged at the plurality of positions, and is selectively arranged at the contact position and the separated position with respect to the photoconductor 11. Then, a developing bias in which a direct current component or a direct current component and an alternating current component are superimposed is applied, and the toner of the color is attached to the surface of the photoconductor 11 from the developing unit in the contact position with respect to the photoconductor 11. Rotary development unit 20
The (developing units 2Y, 2M, 2C, 2K) have a function as developing means.

Intermediate transfer belt 3 of the intermediate transfer unit 30
1 is wound around a tension roller 31A, a drive roller 31B, a tension roller 31C and a driven roller 31D. The tension roller 31A is for surely bringing the intermediate transfer belt 31 into contact with the photoconductor 11. The drive roller 31B is rotationally driven together with the photoconductor 11 by the photoconductor drive motor 36.

As shown in FIG. 3, the intermediate transfer belt 31 is an endless belt formed by joining substantially rectangular sheet bodies at joints 71. In FIG. 3, an arrow 72 indicates a rotation driving direction, and an arrow 73 indicates a rotation axis direction.

The intermediate transfer belt 31 has a rotational axis direction of 7
3 has a protruding portion 74 provided on one end side (upper side in FIG. 3) of 3, and has a transfer inhibition area 75 and a transfer permission area 76. The transfer prohibited area 75 is set in a range of predetermined dimensions on both sides of the seam 71 from one end to the other end in the rotation axis direction 73. Transfer permission area 76
Is a region other than the transfer inhibition region 75 and is set to a rectangular region excluding one end and the other end in the rotation axis direction 73, and the toner image is primarily transferred to the transfer permission region 76. The transfer permission area 76 has a size larger than the A3 size in the long side direction in the rotation drive direction 72, and the A3 size toner image 77 in the long side direction in the rotation drive direction 72 can be transferred.

The vertical synchronization sensor 32 is composed of, for example, a photo interrupter having a light emitting portion (for example, an LED) and a light receiving portion (for example, a photodiode) arranged to face each other, and one end side of the rotating intermediate transfer belt 31 in the rotation axis direction 73. And detects the passage of the protrusion 74 and outputs a detection signal. The detection signal output from the vertical synchronization sensor 32 is used as a vertical synchronization signal that serves as a reference for image formation control by the engine control unit 110. The vertical synchronization sensor 32 is arranged in the vicinity of the driven roller 31D, whereby the intermediate transfer belt 3 is
It is possible to reduce the influence of the bending and the swinging of No. 1 and to stably detect the protruding portion 74.

The belt cleaner 33 is in contact with the intermediate transfer belt 31 by means of the cleaner separation / contact clutch (see FIG. 1).
The middle and solid lines) and the separated state (broken line in FIG. 1) are switchably arranged to scrape off the residual toner on the intermediate transfer belt 31 in the contact state. The contact and separation of the belt cleaner 33 is performed on the transfer prohibited area 75 of the intermediate transfer belt 31. The residual toner on the intermediate transfer belt 31 scraped off by the belt cleaner 33 is collected by the waste toner container 6 disposed immediately below the belt cleaner 33.
Is stored as waste toner.

The gate roller pair 34 is rotationally driven by the driving force of the conveying system driving motor 60 being transmitted when the gate clutch is turned on. The secondary transfer roller 35 is in contact with the intermediate transfer belt 31 (solid line in FIG. 1) and separated (broken line in FIG. 1) by the separation clutch for the secondary transfer roller.
Can be switched. A predetermined secondary transfer bias is applied to the secondary transfer roller 35 while being in contact with the intermediate transfer belt 31, and the intermediate transfer belt 3 is conveyed while conveying the transfer paper 4.
The toner image on No. 1 is secondarily transferred onto the transfer paper 4, and the contact position is set at the secondary transfer portion 37.

A roller-shaped bias applying member (not shown) is in contact with the intermediate transfer belt 31, and a predetermined primary transfer bias is applied to this bias applying member.
The toner image on the photoconductor 11 is primarily transferred to the intermediate transfer belt 31 by the primary transfer bias.

The intermediate transfer belt 31 corresponds to the intermediate transfer medium, the belt cleaner 33 corresponds to the cleaning means, and the bias applying member, the secondary transfer roller 35 and the transfer bias generating circuit 116 (described later) serve as the secondary transfer means. Correspond.

The fixing unit 40 comprises a heating roller 41 and a pressure roller 42, and the transfer paper 4 is made up of the rollers 41 and 42.
The toner on the transfer paper 4 is heated and melted to be fixed on the transfer paper 4 while being conveyed, and has a function as a fixing unit.

From the tip of the paper feed cassette 3 (the right end in FIG. 1), a half-moon-shaped pickup roller 61 is provided upward.
The feed roller pair 62 is disposed, and the gate roller pair 3
4, the secondary transfer roller 35 and the fixing unit 40 are sandwiched, and a conveyance roller pair 63 and a discharge roller pair 64 are further provided, and a conveyance path for the transfer paper 4 (a chain line in FIG. 1) is formed by these. ing.

The pickup roller 61 is driven by a pickup solenoid. The feed roller pair 62, the gate roller pair 34, the secondary transfer roller 35, the heating roller 41 of the fixing unit 40, the conveyance roller pair 63, and the discharge roller pair 64 are the same conveyance system drive motor via the drive force transmission mechanism. It is connected to 60. The transport system driving motor 60 outputs a ready signal when it reaches a predetermined rotation speed. When the feed clutch is turned on, the feed roller pair 62 is rotationally driven by transmitting the driving force of the transport system driving motor 60. The transfer paper 4 has a paper discharge unit 7 provided on the upper portion of the apparatus main body 2 by a discharge roller pair 64.
Is discharged to.

An operation display panel 8 is provided on the upper surface of the apparatus main body 2.
Is provided. The operation display panel 8 is provided with a plurality of operation keys and a display unit made of, for example, a liquid crystal display.

The waste toner container 6 for containing the waste toner of the intermediate transfer belt 31 is provided with a serial EEPROM 81 mounted at a proper position on the outer surface thereof, and the apparatus main body 2
The engine unit 1 further includes a memory interface (memory I / F) 82 and a waste toner full sensor 83.

The serial EEPROM 81 is for storing data indicating whether or not the waste toner container 6 is new. By mounting the waste toner container 6 on the apparatus main body 2, the connector portion of the memory I / F 82 is connected. And is electrically connected to the engine control unit 110 via the memory I / F 82. The waste toner full sensor 83 sends a full detection signal to the CPU 11 of the engine control unit 110 when the waste toner storage amount of the waste toner container 6 becomes full.
When the waste toner storage amount is less than full, for example, a low level signal is sent to the CPU 111, and when it reaches full, a high level signal is sent to the CPU 111. The waste toner full sensor 83 is composed of, for example, a photo interrupter, and its disposition position is set so that the detection level becomes full.

The main controller 100 includes a CPU 101 and a PC.
An interface 102 for transmitting and receiving control signals to and from 200, and an image memory 103 for storing an image signal given via this interface 102 are provided. When the CPU 101 receives a print command signal including an image signal from the PC 200 via the interface 102, the CPU 101 converts the job data into a job data in a format suitable for an operation instruction of the engine unit 1, and sends the job data to the engine control unit 110.

The engine control unit 110 includes a CPU 111,
The ROM 112 and the RAM 113 are provided. ROM
Reference numeral 112 stores a control program of the CPU 111, and the RAM 113 temporarily stores control data of the engine unit 1, calculation results by the CPU 111, and the like.
Data relating to the image signal sent from
Store in 3.

The CPU 111 receives a vertical synchronization signal Vsync from the vertical synchronization sensor 32, a horizontal synchronization signal Hsync from the horizontal synchronization sensor 56, and a serial EEPROM 81 via the memory I / F 82 as input signals from the engine unit 1. The stored data is received, and a full detection signal is received from the waste toner full sensor 83. Then, the CPU 111 controls the operation of each unit of the engine unit 1 based on these input signals and the control program.

That is, the CPU 111 sends a control signal to the motor drive circuit 114 for driving the photoconductor drive motor 36 to synchronously rotate the photoconductor 11 and the intermediate transfer belt 31. Further, the CPU 111 sends a control signal to the motor drive circuit 115 that drives the transport system drive motor 60 to control the transport of the transfer paper 4 from the paper feed cassette 3, and transfers the transfer paper 4 to the intermediate transfer belt. 31 peripheral speed S
Transport at the same speed as 1. Further, the CPU 111 controls the developing units 2Y, 2M, 2C, 2 of the rotary developing unit 20.
The operation of each unit such as K is controlled.

Further, the CPU 111 sends a control signal to a separation clutch driving circuit (not shown) for driving each separation clutch to separate and contact the belt cleaner 33 and the secondary transfer roller 35 with respect to the intermediate transfer belt 31. To control. Further, the CPU 111 sends a control signal to the transfer bias generation circuit 116 that generates a transfer bias to control the application of the primary transfer bias to the bias applying member and the application of the secondary transfer bias to the secondary transfer roller 35. The CPU 111 also controls the operation display panel 8
It receives the operation content of the operation key and controls the display content of the display unit.

Further, the CPU 111 controls the polygon motor 5
A control signal is sent to the motor drive circuit 117 for driving the motor 3 to control the driving of the polygon motor 53. Also, CP
The U111 generates writing pixel data according to an image signal sent from the PC 200 via the CPU 101, and sends the generated writing pixel data as a control signal to the laser light source 51 via the dot counter 118. This dot counter 118 is provided by the CPU 111 to the laser light source 5.
It is a logic circuit that counts the number of write pixels sent to 1 in real time. The written pixel data forms a toner image on the photoconductor 11, and the written pixel number represents the dot number of the toner image.

Further, the CPU 111 adds the count value to a predetermined memory area of the RAM 113 and stores the count value each time the toner counter image formation is completed and the count value of the dot counter 118 is determined. That is, the CPU 111
The number of written pixels is integrated and the integrated value is stored in the RAM 113. Then, the CPU 111 determines the waste toner storage amount of the waste toner container 6 based on the integrated value, and displays the waste toner storage amount on the operation display panel 8 as a ratio to the full toner storage amount according to the determination result. Also, the CPU 111
When the amount of waste toner accommodated in the waste toner container 6 reaches a preset predetermined value close to the full amount detected by the waste toner full sensor 83, the fact is displayed on the operation display panel 6. Hereinafter, this display is referred to as "near end display".

The relationship between the integrated value of the number of written pixels and the ratio of the amount of waste toner stored to the full amount, and the integrated value N1 of the number of written pixels corresponding to a preset value close to the full value are:
It is preset based on the volume of the waste toner container 6 and the relationship between the integrated value and the waste toner storage amount, and is stored in the ROM 112 as part of the control program. The display mode of the operation panel display unit 8 will be described later.

Further, the CPU 111 uses the memory I / F 82.
It is determined whether or not the waste toner container 6 is attached to the apparatus main body 2 based on whether or not the serial EEPROM 81 is connected via. Further, when the CPU 111 determines that the waste toner container 6 is once detached and then reattached to the apparatus main body 2 after the integration of the number of writing pixels is started, the CPU 111 retrieves the storage data of the serial EEPROM 81 and reattaches the same. It is determined whether the waste toner container 6 is new.

When it is determined that the product is new, the integrated value of the number of writing pixels at that time is reset to 0 and the integration is continued. When it is determined that the product is not new, the integrated value is not reset to 0 and the integration is performed. continue.

When the waste toner full sensor 83 detects that the waste toner container 6 is full of waste toner, the CPU 111 displays a warning to that effect on the operation display panel 8 and the image forming operation. It has a function as an image forming control means for stopping the operation.

The serial EEPROM 81 corresponds to the identification means, the memory I / F 82 and the CPU 111 correspond to the container attachment / detachment detection means, the waste toner full sensor 83 corresponds to the full detection means, and the operation display panel 8 is the notification means and the display means. The dot counter 118 corresponds to the dot counting means, and the CPU 111 includes the accommodation amount determining means, the container determining means,
It corresponds to the notification control means and the display control means.

Further, the ROM 112 and the RAM 113 constitute a memory section, and this memory section is EEPRO.
M or other forms of memory may be employed. RAM113
Since the integrated value of the number of writing pixels stored in is required to be stored even when the power is turned off, a backup power supply may be provided, for example. Also, for example, an EEPROM
The integrated value may be stored in a non-volatile memory such as.

Next, the operation of the printer will be described with reference to FIG. FIG. 4 is a timing chart showing the change over time of the state of each part of the engine unit 1.

When a print command signal including an image signal is given to the main control unit 100 from an external device such as a host computer, the engine control unit 110 causes each unit of the engine unit 1 to respond to the control signal from the main control unit 100. Start operation. At this time, if the size of the transfer paper 4 loaded in the paper feed cassette 3 does not match the size instructed by the print command signal, a message prompting the replacement of the paper feed cassette is displayed on the operation display panel 8. To do. In addition, in FIG.
Although the printer is provided with one sheet feeding cassette 3, the present invention is not limited to this and may be a printer having a plurality of sheet feeding cassettes.

Transfer paper 4 loaded in paper feed cassette 3
Is the same as the size instructed by the print command signal (or a cassette for accommodating the transfer paper 4 of the size instructed by the print command signal is included in the plurality of paper feed cassettes. ), The transport system drive motor 60 is first turned on at time t1 as shown in FIG. Then, when the ready signal is output from the transport system driving motor 60 at time t2, the driving of the photoconductor driving motor 36 is started, the intermediate transfer belt 31 is driven at a predetermined peripheral speed S1, and the vertical synchronization signal is output. The Vsync is periodically output and the driving of the polygon motor 53 is started. Then, when the ready signal is output from the polygon motor 53 at time t3, it is effectively accepted from the next vertical synchronization signal Vsync, the surface of the photoconductor 11 is uniformly charged by the charging unit 12, and the surface of the photoconductor 11 is received. , An electrostatic latent image corresponding to the image signal is formed by the laser beam 57 from the exposure unit 50, and the electrostatic latent image is developed by the rotary developing unit 20 to form a toner image. Primary transfer is performed on the intermediate transfer belt 31 in the next transfer unit 14.

That is, the intermediate transfer belt 31 is rotated by the driving of the photoconductor driving motor 36, and the time t4, t5,
The vertical synchronization signal Vsync is output at t6 and t7, respectively. A predetermined time T from the falling edge of each vertical synchronization signal Vsync
After one time, the image request signal Vreq is output, and upon the falling of the image request signal Vreq, the formation of the electrostatic latent image corresponding to the image signal is started and the developing bias is turned on.

Then, the developing units of the rotary developing section 20 are switched at times t4, t5, t6, and t7 so that toner images of respective colors are formed on the photoconductor 11 and sequentially primary-transferred onto the intermediate transfer belt 31. It During this time, the secondary transfer roller 35 is separated from the intermediate transfer belt 31, so that the toner images of the respective colors are superposed on the intermediate transfer belt 31. The developing bias is at time t4, t5, t
It is turned off after a predetermined time T2, which is predetermined by the transfer paper size, from the falling point of each vertical synchronization signal Vsync of 6 and t7. As a result, the toner images Y, C, M and K are superimposed on the transfer permission area 76 of the intermediate transfer belt 31.

On the other hand, the uppermost transfer paper 4 of the transfer paper stack loaded in the paper feed cassette 3 is taken out by the pickup roller 61, conveyed by the feed roller pair 62 at a predetermined speed, and nipped by the gate roller pair 34. It Then, the gate clutch is turned on in synchronization with the toner image on the intermediate transfer belt 31, and the gate roller pair 3
The transfer paper 4 is conveyed from 4 to the secondary transfer unit 37.

Then, after a lapse of a predetermined time from time t8 when the vertical synchronizing signal Vsync falls, the separation clutch for the secondary transfer roller is turned on, the secondary transfer roller 35 abuts on the intermediate transfer belt 31, and subsequently. Then, the application of the secondary transfer bias from the transfer bias generation circuit 116 to the secondary transfer roller 35 is turned on at a time t9 after a predetermined time from the time t8. As a result, the color toner image in which the toner images Y, C, M, and K that have been primarily transferred to the transfer permission area 76 of the intermediate transfer belt 31 are superimposed is transferred to the transfer paper 4.

The gate clutch is turned off after the transfer paper 4 is carried out, and the application time T3 of the secondary transfer bias is preset according to the size of the transfer paper 4. After the application of the secondary transfer bias is turned off, the separation clutch for the secondary transfer roller is turned on, and the secondary transfer roller 35 is separated from the intermediate transfer belt 31. Then, in the fixing unit 40, the toner image is fixed on the transfer paper 4 while the transfer paper 4 is being conveyed. The transfer paper 4 is further transported by the transport roller pair 63, and is discharged to the paper discharge unit 7 by the discharge roller pair 64.

After the image formation, if the next print command signal is not input, the charging unit 12 is turned off at time t10, which is the falling point of the vertical synchronization signal Vsync, and the primary transfer bias is passed after a predetermined time from time t10. Is turned off, then
At a time t11, which is a predetermined time after the time t10, the photoconductor drive motor 36 starts decelerating, and at the time t12 when the photoconductor drive motor 36 stops, the laser light source 51 is turned off and the transport system drive motor 60 is generated. Is turned off. The polygon motor 53 is turned off at time t13, which is a preset standby time T4 (for example, T4 = 30 seconds in the present embodiment) from time t12.

Next, with reference to FIG. 5, the integration of the number of written pixels by the CPU 111 will be described. FIG. 5 is a timing chart showing the integration timing.

Since the dot counter 118 counts the number of writing pixels sent from the CPU 111 to the laser light source 51 in real time, the number of writing pixels is determined at the timing when writing of one image is completed. Therefore, the CPU 1 of the number of written pixels (count value by the dot counter 118)
The integration by 11 is performed for each image signal Y1, C1, M1, K
It is performed at the end of 1, K2 and K3. In the example of FIG. 5, the integrated value reaches the predetermined value N1 when the image signal K3 ends and the number of written pixels is integrated, and the near-end display is performed at this point.

Next, the display control of the waste toner storage amount of the waste toner container 6 by the CPU 111 will be described with reference to FIG. FIG. 6 is a diagram showing an example of a display mode of the waste toner storage amount displayed on the operation display panel 8.

FIG. 6 shows an example in which the ratio of the amount of waste toner accommodated to the full amount is displayed as a bar on the liquid crystal display of the operation display panel 8, and here, it is indicated that it is 60% of the full amount. This bar display may be changed stepwise, for example, every 20%, or may be changed steplessly. Here, the predetermined value N1 is, for example, 80%
When the value corresponding to is set to, the near end display is performed by blinking the bar when 80% is reached. Note that, for example, display control is performed so that the bar gradually extends between 80% and 100%, and when the waste toner full sensor 83 detects that the waste toner is full, the bar is made to coincide with 100% and the bar is displayed by blinking. A warning may be displayed.

Next, with reference to FIG. 7, a procedure for determining the storage amount of the waste toner container 6 by the CPU 111 will be described.
FIG. 7 is a flowchart showing the same procedure.

First, the integrated value of the number of written pixels stored in a predetermined area of the RAM 113 is reset to 0 (# 1
0), then it is determined whether or not the count value of the dot counter 118 has been determined (# 12). If not determined (NO in # 12), the count value is determined as described in FIG. Wait until you do.

When the count value of the dot counter 118 is confirmed (YES in # 12), the number of written pixels is integrated (# 14), and as shown in FIG. Toner capacity is displayed as a bar (# 1
6).

Next, it is judged whether or not the integrated value N is equal to or more than the predetermined value N1 (# 18), and if N ≧ N1 (YES in # 18), near end display is performed on the operation display panel 8. (# 20) and proceed to # 22.

On the other hand, if N <N1, (N in # 18
O), the process proceeds directly to # 22, and it is determined whether or not the waste toner storage amount of the waste toner container 6 is full based on the detection result of the waste toner full sensor 83, and if full (YE in # 22).
S), a predetermined operation stop process is performed (# 24), and this routine ends.

On the other hand, if not full (NO in # 22),
Based on the input data from the serial EEPROM 81, it is determined whether or not the waste toner container 6 is once removed and reattached (# 26), and if not, it is reattached (# 26).
NO), and returns to # 12.

On the other hand, if reattachment is detected (Y in # 26,
ES), based on the input data from the serial EEPROM 81, it is determined whether or not the re-installed waste toner container 6 is a new product (# 28), and if it is not a new product (N in # 28).
O), return to # 12.

On the other hand, if the re-installed waste toner container 6 is new (YES in # 28), the integrated value N of the number of writing pixels stored in the predetermined area of the RAM 113 is reset to 0 (# 30). The bar display of the waste toner storage amount is reset to 0 (# 32), and the process returns to # 12.

As described above, according to the present embodiment, the number of writing pixels forming an image is counted by the dot counter 118, the CPU 111 integrates the counted value, and the waste toner in the waste toner container 6 is calculated by the accumulated value. The storage amount is determined, and in particular, since the residual toner on the intermediate transfer belt 31 is proportional to the toner usage amount with relatively high accuracy,
By using the integrated value of the number of written pixels, which is a value corresponding to the toner usage amount, it is possible to accurately determine the waste toner storage amount of the waste toner container 6.

Further, according to this embodiment, since the progress of the waste toner storage amount of the waste toner container 6 is displayed on the operation display panel 8, the waste toner storage amount is suddenly changed while the apparatus is in use. It is possible to improve the usability of the apparatus by eliminating the inconvenience of being informed of fullness, and preparing a new waste toner container 6 for replacement in advance.

Further, according to the present embodiment, the serial EE
A PROM 81 is provided to enable detection of whether or not the waste toner container 6 is a new product, and enable removal and reattachment of the waste toner container 6 during integration of the number of writing pixels, and determine the detection result according to the detection result. I am trying to change the integration procedure. That is, when the re-installation of the waste toner container 6 is detected, if the re-installed waste toner container 6 is a new product, the integrated value is reset to 0 and integration is performed. If it is not a new product, the integrated value is not reset to 0. It continues to accumulate the total. Therefore, the waste toner storage amount can be accurately determined.

The present invention is not limited to the above embodiment, and various changes can be made to the above without departing from the spirit of the invention. For example, the following modification (1) )-(13) can be adopted.

(1) Serial EEPRO of the above embodiment
M81 stores only data indicating whether or not the product is new, but the present invention is not limited to this, and identification data for individually identifying the waste toner container 6 may be stored. In addition, for example, when the outer lid of the apparatus main body 2 is opened, the CPU 111 determines the amount of waste toner stored in the waste toner container 6 by serial E.
It may be written in the EPROM 81. In this case, even if the power is turned off or the waste toner container 6 is once detached and then reattached, the amount of waste toner accommodated in the reattached waste toner container 6 can be accurately grasped. Even after the re-mounting, the waste toner storage amount can be accurately displayed in the same manner.

(2) The waste toner container 6 is a serial EEPR
The engine unit 1 includes a memory I / F 8 instead of the OM 81, and includes a code display unit including a barcode and a two-dimensional code.
Instead of 2, a code reading unit having an infrared sensor may be provided. In this case, the CPU 111
When the waste toner container 6 is reattached, it is determined that the same code is not a new product, and if the different code is a new product.

The waste toner container 6 is a serial EEPR.
Instead of the OM 81, a fuse for judging a new product may be provided. In this case, if the fuse is not blown when the waste toner container 6 is attached, the CPU 111 determines that the fuse is new and controls the fuse to be blown. If the fuse is blown, the CPU 111 determines that the fuse is not new. Good.

(3) Although the waste toner full sensor 83 is provided in the above embodiment, the present invention is not limited to this, and it is determined whether the waste toner storage amount is full based on the integrated value of the number of writing pixels counted by the dot counter 118. You may do it.
In this case, the CPU 111 has a function as a fullness determining unit. According to this mode, it is possible to reduce the number of parts and reduce the size of the apparatus body 2.

(4) In the above embodiment, the progress of the waste toner storage amount is always displayed as a bar. However, the present invention is not limited to this, and when a predetermined operation is performed on the operation keys of the operation display panel 8. You may make it display only on. In addition,
Even in this case, the integrated value of the number of written pixels is the predetermined value N1.
The near end display should be automatically performed when the value reaches.

(5) In the above embodiment, the progress of the waste toner storage amount is displayed by the bar display. However, the present invention is not limited to this. For example, as shown in FIG. 8, only a near end display and a full display are performed. You may do it. FIG. 8 is a diagram showing another example of the display mode of the waste toner storage amount of the waste toner container 6 displayed on the operation display panel 8. Figure 8
Then, the operation display panel 8 has a green LED 121 and a red L
An ED 122 is provided and the green LED 121 is shown to be lit.

In this embodiment, when the integrated value of the number of written pixels reaches the predetermined value N1, the CPU 111 outputs the green LE.
Turn on D121. The lighting of the green LED 121 informs that the waste toner storage amount is almost full. Further, the CPU 111 causes the red LED 12 to operate when the waste toner full sensor 83 detects that the waste toner storage amount is full.
Turn on 2. The lighting of the red LED 122 notifies that the waste toner container 6 is full.

(6) In the above embodiment, the user is notified by a near-end display or a full display, but the present invention is not limited to this. For example, a sound generating unit such as a buzzer is provided, and a sound generated by this sound generating unit is provided. May be notified to the user. In this case, the voice generation unit corresponds to the notification means.

(7) In the above embodiment, the operation display panel 8 is configured to display near-end display or full display, but the present invention is not limited to this, and it may be displayed on the PC 200. Moreover, you may notify by the sound of PC200. In this case, the PC 200 corresponds to the display means and the notification means.

(8) In the above embodiment, the count value of the number of written pixels by the dot counter 118 is integrated as it is, but the present invention is not limited to this, and it is preset according to the volume of the waste toner container 6 and the like. You may make it add an offset value. According to this aspect, it becomes possible to more accurately determine the waste toner storage amount. In addition,
In this case, the set offset value may be stored in the ROM 112 as a part of the control program.
The OM 112 has a function as an offset value storage unit.

(9) In the above embodiment, the number of written pixels is directly counted by the dot counter 118, but the number of pixels is not limited to this, and is set for each type by discriminating it according to the image type such as discrete dots or continuous dots. It is also possible to multiply by the above coefficient and count, or to set a different coefficient for each color, and to count the number of writing pixels of each color, multiply by the corresponding coefficient and then count. According to this aspect, it becomes possible to more accurately determine the waste toner storage amount. In this case,
ROM1 with the set coefficient as part of the control program
The ROM 112 has a function as a coefficient storage unit. Further, in this form, the offset value of the modified form (8) may be further added.

(10) In the above embodiment, the waste toner storage amount sensor 83 is composed of a photo interrupter, but the waste toner storage amount sensor 83 is not limited to this, and may be another sensor such as a reflection type optical sensor, a capacitance sensor, or a weight sensor. You may comprise.

(11) In the above embodiment, the number of written pixels is counted in real time by the dot counter 118, but the method of counting the number of written pixels is not limited to this. For example, the image memory 103 by the CPU 101
It is also possible to scan the image signal stored in (1) to count the number of written pixels and send the count value to the CPU 111. Further, in the above embodiment, the CPU 111 uses the CP
The data relating to the image signal sent via U101 is converted to R
It is stored in AM113, but this RAM1
The number of written pixels may be counted by scanning the image signal in the state stored in 13. In these cases, C
The PU 101 or the CPU 111 corresponds to the dot counting means.

(12) In the above-described embodiment, the color printer is provided with one photosensitive member and the toners of four colors are superposed by rotating the intermediate transfer belt 31, but the present invention is not limited to this, and the intermediate transfer belt 31, for example, is used. A so-called tandem color printer having four photoconductors arranged side by side may be used.

(13) In the above embodiment, a printer that prints an image provided by an external device such as a host computer on a transfer paper is used for explanation, but the present invention is not limited to this, and a copying machine or a facsimile is used. The present invention can be applied to a general electrophotographic image forming apparatus including an apparatus.

[0093]

As described above, according to the first and sixth aspects of the invention, the number of pixels forming a toner image is counted, the counted number of pixels is integrated, and the waste toner is calculated based on the integrated value. The amount of waste toner stored in the container is determined. Since the residual toner on the intermediate transfer medium is almost proportional to the toner usage amount, by using the integrated value of the number of pixels which is a value corresponding to the toner usage amount, The amount of waste toner stored can be accurately determined.

According to the second aspect of the present invention, the waste toner container is provided with the identification means and the waste toner container based on the identification means. Since it is possible to identify the waste toner container and determine whether or not the waste toner container is new, it is possible to prevent erroneous determination of the waste toner storage amount.

According to the third aspect of the invention, when it is detected that the waste toner container is attached to the apparatus main body, it is determined whether or not the waste toner container is a new one, and the waste toner container is a new one. When it is determined, the integrated value of the number of pixels is reset to 0,
When it is determined that the waste toner container is not a new product, the integration is continued without resetting the integrated value of the number of pixels to 0. Therefore, when the waste toner container is replaced with a new one, it is used as it is without being replaced with a new product. In either case, it is possible to prevent erroneous determination of the waste toner storage amount.

Further, according to the invention of claim 4, it is surely prevented that the waste toner overflows into the waste toner container by detecting whether or not the waste toner storage amount of the waste toner container is full. can do. Also, when the waste toner storage amount reaches a preset predetermined value which is almost full, the user is informed of that fact by the notification means. The inconvenience that the fullness is detected is eliminated, and a new waste toner container for replacement can be prepared in advance, so that the usability of the apparatus can be improved.

Further, according to the invention of claim 5, since the waste toner storage amount is displayed on the display means, the disadvantage that the waste toner storage amount suddenly becomes full during use of the apparatus is solved. Therefore, it is possible to improve the usability of the apparatus, for example, by preparing a new waste toner container for replacement in advance.

[Brief description of drawings]

FIG. 1 is a diagram showing an internal configuration of a printer which is an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a block diagram showing an electrical configuration of the printer.

FIG. 3 is a development view of an intermediate transfer belt.

FIG. 4 is a timing chart showing changes over time in states of various parts of the engine unit.

FIG. 5 is a timing chart showing the integration timing of the number of written pixels by the CPU.

FIG. 6 is a diagram showing an example of a display mode of a waste toner storage amount of a waste toner container displayed on an operation display panel.

FIG. 7 is a flowchart showing a procedure for determining a waste toner storage amount of a waste toner container by a CPU.

FIG. 8 is a diagram showing another example of the display mode of the waste toner storage amount of the waste toner container displayed on the operation display panel.

[Explanation of symbols]

6 waste toner container 8 operation display panel (informing means, display means) 11 photoconductor 31 intermediate transfer belt (intermediate transfer medium) 35 secondary transfer roller (secondary transfer means) 51 laser light source 81 serial EEPROM (identification means) 82 memory I / F (container attachment / detachment detection means) 83 Waste toner full sensor (full detection means) 110 Engine control unit 111 CPU (accommodation amount determination means, container determination means, container attachment / detachment detection means, notification control means, display control means) 112 ROM 116 transfer bias generation circuit (secondary transfer means) 118 dot counter (dot counting means)

Continued front page    F-term (reference) 2H134 GA06 GB02 HD00 JB02 JB07                       KA24 KA25 KA26 KA40 KB15                       KB20 KH15 KJ02                 2H200 FA12 GA23 GA34 GA44 GA47                       GA50 GB12 GB25 GB43 HA02                       HA12 HA28 HB03 HB12 HB22                       HB26 JA02 JB10 JC03 JC12                       LA12 LB02 LB09 LB13 LB17                       LB39 LB40 PA27 PA28 PB11                       PB26 PB29 PB38

Claims (6)

[Claims] 1. An image forming apparatus comprising an intermediate transfer medium on which a toner image formed on a photoconductor is primarily transferred, and a secondary transfer means for secondarily transferring the toner image on the intermediate transfer medium onto a transfer paper. A cleaning unit that removes toner remaining on the intermediate transfer medium after the secondary transfer, a waste toner container that stores waste toner removed from the intermediate transfer medium by the cleaning unit, and the toner image is formed. A dot counting unit that counts the number of pixels, and a storage amount determination unit that determines the waste toner storage amount of the waste toner container based on the integrated value of the number of pixels counted by the dot counting unit An image forming apparatus characterized by the above. 2. The image forming apparatus according to claim 1, further comprising: an identification unit provided on the waste toner container, and a container identification unit for identifying the waste toner container based on the identification unit. . 3. A container attachment / detachment detecting means for detecting attachment / detachment of the waste toner container to / from the apparatus main body, wherein the container discriminating means detects the attachment / detachment of the waste toner container to the apparatus main body by the container attachment / detachment detection means. When the waste toner container is detected, it is determined whether or not the waste toner container is new based on the identification unit. The storage amount determination unit determines that the waste toner container is new by the container determination unit. The image forming apparatus according to claim 2, wherein the integrated value is reset to 0 when it is determined that the product is not new, and the integration is continued without resetting the integrated value to 0. 4. A fullness detecting means for detecting whether or not the waste toner storage amount of the waste toner container is full, an informing means for informing a user of predetermined notification contents, and the storage amount determining means. And a notification control means for notifying the user by means of the notification means when the amount of waste toner stored determined by means of a predetermined value close to the full detected by the full detection means is reached. The image forming apparatus according to claim 1, further comprising: 5. The display device further comprises display means for displaying a predetermined display content, and display control means for displaying the waste toner storage amount determined by the storage amount determination means on the display means. The image forming apparatus according to any one of claims 1 to 4. 6. A toner image is formed on a photoconductor, the toner image of the photoconductor is primarily transferred to an intermediate transfer medium, the toner image of the intermediate transfer medium is secondarily transferred to a transfer paper, and the secondary image is formed. An image forming method in which toner remaining on the intermediate transfer medium after transfer is removed, and a dot counting step of counting the number of pixels forming the toner image; and containing waste toner removed from the intermediate transfer medium An image forming method, comprising: a storage amount determination step of determining a storage amount of waste toner in a waste toner container based on an integrated value obtained by integrating the number of pixels counted in the dot counting step.