JP2766046B2 - Electrophotographic printing equipment - Google Patents

Description

The present invention relates to an image forming cartridge which is a replaceable consumable in which a photosensitive drum, a developing device, a cleaner and the like are integrally formed, and is formed on the photosensitive drum. The present invention relates to an electrophotographic printing apparatus that forms a visible image with a developer corresponding to an electrostatic latent image, and transfers the visible image to printing paper for printing.

(Prior Art) Conventionally, in the above-described electrophotographic printer, there has been proposed an electrophotographic printer in which a developing device, a photosensitive drum, a cleaner, and the like are integrally formed to form a cartridge, which is exchangeably attached to a printer main body. FIG. 6 shows an electrophotographic printer having such a cartridge, which will be described below with reference to the drawings.

In FIG. 6, a paper cassette 2 is mounted on the electrophotographic printer 1, and paper 3 is stored in the paper cassette 2. A paper feed roller 4 is provided at the leading end of the paper cassette 2.
Is attached, and paper 3 is supplied one by one into the printer. Feed rollers 5 are provided at various places along the travel path of the paper 3.

An image forming cartridge 6 is disposed substantially at the center of the printer 1. As shown in FIG. 7, the image forming cartridge 6 includes a photosensitive drum 7 for forming an electrostatic latent image on its surface,
A developing roller 8 for supplying toner as a developer to the photosensitive drum 7, a sponge roller 9 for supplying toner to the developing roller 8, a stirring shaft 10 for uniformly supplying toner to the sponge roller 9, and a uniform surface of the photosensitive drum 7 A primary charger 11 for charging and a cleaner unit 12 for collecting toner remaining on the surface of the photosensitive drum 7 are integrally formed, and are replaceable with respect to the main body of the printer 1. Reference numeral 13 denotes a developing unit. FIG. 7 is a side view showing the image forming cartridge. The image forming cartridge 6 also includes
Developing blade 8a for regulating the thickness of the toner layer on developing roller 8
Is installed. A toner cartridge 14 filled with toner 19 is detachably mounted substantially above the stirring shaft 10. The toner cartridge 14 has an opening 14a, and a shutter 14b is rotatably mounted.

In FIG. 6, above the image forming cartridge 6
The LED head 15 is disposed and forms an electrostatic latent image on the charged surface of the photosensitive drum 7. A transfer unit 16 is located below the photosensitive drum 7, where the image on the printing paper 3 is transferred. A heat fixing roller 17 is disposed downstream of the sheet traveling path, and fixes an image on the sheet 3. Further, a stacker 18 for receiving a printed sheet is provided downstream of the sheet traveling path.

In the electrophotographic printer having the above structure, the following operation is performed. When the toner cartridge 14 is mounted on the image forming cartridge 6 and the shutter 14b rotates, the toner 19 in the toner cartridge 14 drops from the opening 14a to the developing unit 13 in the image forming cartridge 6. This toner 19
Is supplied to the developing roller 8 by the stirring shaft 10 and the sponge roller 9. The thickness of the toner 19 attached to the surface of the developing roller 8 is regulated by the developing blade 8a, and is sent to the photosensitive drum 7 side. On the other hand, the photosensitive drum 7 is a primary charger.
After the surface is uniformly charged by 11, the electrostatic latent image is formed on the surface by the LED head 15. The toner 19 adheres to the electrostatic latent image from the developing roller 8 and development is performed. On the other hand, printing paper 3 is fed from the paper cassette 2 into the apparatus by the paper feed roller 4. The feeding timing of the paper 3 is synchronized with the rotation of the photosensitive drum 7.
The developed image on the surface is sent so as to be transferred onto the paper 3. The transfer of the image is performed by the transfer device 16. The image on the paper 3 after the transfer is fixed by the heat fixing roller 17 to complete the printing, and is sent to the stacker 18.

After the transfer, the toner 19 remaining on the surface of the photosensitive drum 7 is scraped off by the cleaning blade 12a of the cleaner unit 12 to prepare for the next printing.

In particular, the life of the image forming cartridge 6 is caused by wear of the surface of the photosensitive drum 7 during repeated printing operations, thereby changing the charge amount of the photosensitive drum 7 and consequently deteriorating print quality. Therefore, conventionally, as a method of detecting the life of the image forming cartridge 6, a method of providing a surface potential sensor for detecting the charge amount of the photosensitive drum 7 and judging whether or not the life of the image forming cartridge has reached the life based on the detected value is known. Had been taken. Alternatively, for a small-sized apparatus, a method is provided in which a counter for counting the number of rotations of the photosensitive drum 7 is provided, and the life is determined when the total number of rotations of the photosensitive drum 7 exceeds a specified value.

On the other hand, the toner cartridge 14 must be replaced with a new one when all the toner 19 inside is consumed. For this reason, conventionally, the time for replacing the toner cartridge 14 has been determined by detecting the remaining amount of the toner 19. Generally, the image forming cartridge 6 has a life that consumes an amount of toner equivalent to several toner cartridges 14. Therefore, conventionally, the toner cartridge 14 has been made detachable from the image forming cartridge 6 so that only the toner cartridge 14 can be replaced. The toner cartridge 14 cannot be removed unless the shutter 14b shown in FIG. 7 closes the opening 14a, and if the toner 19 is near the opening 14a, the toner cartridge 14 is opened and closed by the opening and closing operation of the shutter 14b.
Since the toner 19 enters between itself and the main body, the operation is performed only when the toner 19 does not exist near the opening 14a.

(Problems to be Solved by the Invention) However, in the above-described conventional cartridge replacement method, the toner cartridge can be removed from the image forming cartridge only when the toner inside is completely consumed and the toner is exhausted near the opening. The image forming cartridge may reach the end of its life when toner is still sufficiently remaining in the toner cartridge. In this case, the toner cartridge must be replaced with a new one together with the image forming cartridge. Therefore, the toner was wasted.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object that when the life of an image forming cartridge is approaching, even if the amount of toner becomes short thereafter, a new toner cartridge is not replaced and the used toner ends. An object of the present invention is to provide a cartridge replacement method which does not waste toner and has excellent running cost by replacing the image forming cartridge at the time when the cartridge is replaced.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides an image carrier, a developing means, and a developer accommodating portion which are integrally formed, and the developer accommodating portion is provided with a developer supply container. An electrophotographic printing apparatus having an image forming cartridge capable of replenishing an agent, a measuring unit for measuring the progress of the life of the image forming cartridge, a detecting unit for detecting the presence or absence of a developer in the image forming cartridge, A life data output unit for outputting a preliminary life value obtained by subtracting a developer consumption life value of a developer supply container from a predetermined life value of a forming cartridge, and comparing the life progress and the preliminary life value with the life of the image forming cartridge. An image forming cartridge life determining unit for determining a state; and a developer remaining amount determining unit for determining a remaining amount state of the developer in the image forming cartridge based on an output of the detecting unit. When the control unit determines that there is no developer in the image forming cartridge before the life progress of the image forming cartridge reaches the preliminary life value. Outputs a developer supply request to the output unit,
When it is determined that the developer is present in the image forming cartridge after the image forming cartridge reaches the preliminary life value, a notification to suppress the supply of the developer is output to the output unit, and then the developer is stored in the image forming cartridge. If it is determined that the image forming cartridge is not present, a request to replace the image forming cartridge having a different output from the notification of suppressing the supply of the developer is output to the output unit.

(Operation) Next, the operation will be described.

The progress of the life of the image forming cartridge is measured by the measuring means. Then, as a result of the measurement, the determination unit determines whether the life progress of the image forming cartridge has reached a predetermined progress. As a result, if the life of the image forming cartridge has reached the predetermined life, the detecting means determines whether or not the developer remains in the developer cartridge, and if not, notifies the output means of a request to replace the image forming cartridge. To do it. Therefore, the image forming cartridge is replaced only when the developer remains in the developer cartridge, so that the developer is not wasted.

(Example) Hereinafter, an example according to the present invention will be described with reference to the drawings. Elements common to the drawings are assigned the same reference numerals.

FIG. 1 is a block diagram showing an embodiment according to the present invention.
FIG. 3 is a functional block diagram showing an embodiment according to the present invention, and FIG. 3 is a side view showing an image forming cartridge of the embodiment.

First, in FIG. 3, a detection sensor 22 for detecting the presence or absence of the toner 19 in the developing unit 13 is attached to the image forming cartridge 21 of this embodiment. A piezoelectric element is provided on the toner detection surface of the detection sensor 22 to detect the presence or absence of the toner 19 by detecting a change in the load due to the toner 19, thereby detecting the presence or absence of the toner 19 in the toner cartridge 14. The other structure of the image forming cartridge 21 is the same as that of the conventional example, and the description is omitted.

An electrical structure of the embodiment will be described with reference to FIG. twenty three
Is a control unit for controlling the operation of the electrophotographic printer according to the present invention, which comprises a central processing unit (CPU). Control unit 2
A read-only memory (ROM) 24, a random access memory (RAM) 25 and an I / O port 26 are connected to 3, and an EEPROM 27 and an operation panel 28 are further connected to the I / O port 26. The ROM 24 stores a control program and the like for operation control, and the RAM 25 temporarily stores data. EEPROM2
Reference numeral 7 denotes a memory for storing the total rotation time of the photosensitive drum, which will be described later. An operation panel 28 is provided in the main body of the electrophotographic printer, and mainly comprises a display unit 29 and various operation switches 30, as shown in FIG. ing. The display unit 29 includes a liquid crystal display device. FIG. 4 is an explanatory view showing the operation panel of the embodiment.

In FIG. 1, a timer 31 and the above-described toner detection sensor 22 are further connected to the control unit 23. The timer 31 measures the rotation time of the photosensitive drum 7 in the image forming cartridge 21.

Next, a more detailed structure of the control unit 23 will be described with reference to FIG. The control unit 23 includes a writing unit 32 for instructing the EEPROM 27 to write data, and a reading unit 33 for reading data from the EEPROM 27. Further, a memory 34 is provided, in which the average rotation time of the photosensitive drum 7 required to consume one toner cartridge 14 is subtracted from the total rotation time of the photosensitive drum 7 as a life. The stored value (T1) is stored. For example, assuming that the photosensitive drum 7 has a life enough to consume five toners of the toner cartridge 14 on average, the memory 34 stores in the memory 34 the photosensitive drum 7 consumes four toners of the toner cartridge 14. The value of the total rotation time until the operation is performed is stored.

The controller 23 also includes a first judging unit 35 for comparing and judging the data read by the reading unit 33 with the data in the memory 34, and a judgment result by the first judging unit 35 and the toner detection sensor 22
The life status of the image forming cartridge 21 and the remaining amount of toner are determined based on the detection result of
Is provided with a second determination means 36 for outputting the determination result.

In FIG. 3, the operation of the image forming cartridge 21 is as described in the conventional example. That is, the toner cartridge
When 14 is mounted on the image forming cartridge 21 and rotated,
The shutter 14b is opened and the toner 19 is moved to the image forming cartridge 21.
Fall into. The toner 19 is sent to the developing roller 8 by the stirring shaft 10 and the sponge roller 9, and the developing blade
The layer thickness is regulated by 8a, and is sent to the photosensitive drum 7 side.
After the surface of the photosensitive drum 7 is uniformly charged by the primary charger 11, an electrostatic latent image is formed by the LED head and comes into contact with the developing roller 8. Here, the electrostatic latent image is developed by the toner 19 and moves to the transfer position on the printing paper. The toner 19 remaining on the surface of the photosensitive drum 7 after the transfer is collected by the cleaning unit 12,
A series of electrophotographic processes ends. The surface of the photosensitive drum 7 is worn by the series of printing operations, and the amount of charge changes, thereby extending the life of the image forming cartridge 21.

Next, the operation of displaying the life status of the image forming cartridge and the remaining toner status of the toner cartridge will be mainly described as a fifth operation.
The description will be made according to the flowchart shown in FIG. FIG. 5 is a flowchart showing the operation of the embodiment.

The timer 31 shown in FIG. 2 measures the rotation time of the photosensitive drum 7. The rotation time measured during the printing operation is written into the EEPROM 27 by the writing means 32 of the control unit 23. This writing is performed via the RAM 25 and the I / O port 26 shown in FIG. The total rotation time of the photosensitive drum 7 up to that time is immediately stored in the EEPROM 27, and the total rotation time is updated by performing new writing. When the EEPROM 27 is updated, the updated value is read by the reading means 33 of the control unit 23 (step 1). The read total rotation time T0 is determined by the first determination means 35.
Sent to The value of T1 described above is read from the memory 34, and is compared with the total rotation time T0 read from the EEPROM 27 by the first determination means 35 (step 2). As a result, when the total rotation time T0 of the photosensitive drum 7 is longer than T1, it is considered that the life of the photosensitive drum 7 is approaching. However, as a next process, the detection result of the toner detection sensor 22 is determined by the second determination unit 36. A determination is made (step 3). As a result, if toner remains, a message indicating that the life of the photosensitive drum 7 is approaching is displayed on the display unit 29 of the operation panel 28 shown in FIG. 4 (step 4). In this embodiment, it is displayed as "drum jumyo gazuki mashita". By displaying in this manner, when the life of the image forming cartridge is approaching, the operator is warned that the toner will not be replaced with a new toner cartridge even when the amount of toner becomes short thereafter, and the operator is prompted to prepare a new image forming cartridge. If the result of the determination by the second determination means 36 is that no toner remains, the display unit 29 displays "Drum ヲ Replace" (step 5). This prompts the operator to replace the image forming cartridge 21.

In step 2, the total rotation time of the photosensitive drum 7 is determined.
If T0 has not reached T1, the detection result of the toner detection sensor 22 is determined by the second determination means 36 (step 6). If no toner remains, the display unit 29 displays "toner discharge". Display and toner cartridge
Prompt for replacement of 14. In this case, the life of the photosensitive drum 7 does not expire even if it is replaced with a new toner cartridge or at least one toner is consumed. If the toner still remains, the display unit 29 displays “Insert” and continues the printing operation.

As described above, in the present embodiment, the image forming cartridge is not replaced unless the toner in the toner cartridge ends, so that waste of toner is eliminated. When the image forming cartridge is replaced, the life of the image forming cartridge itself is already approaching, so that the waste is not so much.

In the above embodiment, the total rotation time of the photosensitive drum is measured to measure the progress of the life of the image forming cartridge. However, the present invention is not limited to this, and the total number of rotations of the photosensitive drum may be measured. In this case, it goes without saying that the value of T1 described above is a value obtained by subtracting the rotation speed of one toner cartridge from the total rotation speed of the photosensitive drum.

Further, a method using sound may be used as a means for outputting the determination result.

(Effects of the Invention) As described above in detail, according to the present invention, the image forming cartridge is set to a preliminary life value obtained by subtracting a developer consumption life value for the developer supply container from a predetermined life value of the image forming cartridge. When the life of the cartridge has reached the end of its life, a notification is output to the output unit to suppress the replenishment of the developer when the developer is present, so that the operator is prevented from replenishing the image forming cartridge with the new developer and then developing. When it is determined that the developer has been consumed and there is no more developer in the image forming cartridge, a request for replacing the image forming cartridge is output, so that the developer is consumed without waste and the image forming cartridge also maintains the print quality to the end. After that, it has an effect of being able to be used up to near the service life.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment according to the present invention, FIG. 2 is a functional block diagram showing an embodiment according to the present invention, FIG. 3 is a side view showing an image forming cartridge of the embodiment, and FIG. FIG. 5 is an explanatory view showing an operation panel of the embodiment, FIG. 5 is a flowchart showing the operation of the embodiment, FIG. 6 is a schematic side view of an electrophotographic printer, and FIG. 7 is a side view showing an image forming cartridge. 7 ... Photosensitive drum, 14 ... Toner cartridge, 19 ...
Toner, 21 ... Image forming cartridge, 22 ... Toner detection sensor, 23 ... Control unit, 29 ... Display unit, 31 ... Timer.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G03G 21/00 370-540 G03G 15/08

Claims (1)

(57) [Claims] An image forming cartridge in which an image carrier, a developing means, and a developer accommodating portion are integrally formed, and an image forming cartridge capable of replenishing the developer accommodating portion with a developer from a developer replenishing container. In the photographic printing apparatus, a measuring unit for measuring a life progress of the image forming cartridge; a detecting unit for detecting the presence or absence of a developer in the image forming cartridge; A life data output unit for outputting a preliminary life value obtained by subtracting a developer consumption life value of the developer supply container, and a life of the image forming cartridge for comparing the life progress and the preliminary life value to determine a life state of the image forming cartridge. Determining means for determining a remaining amount of the developer in the image forming cartridge based on an output of the detecting means; And an output unit that outputs a determination result of the control unit. The control unit determines that there is no developer in the image forming cartridge before the life progress of the image forming cartridge reaches the preliminary life value. In this case, a developer replenishment request is output to the output unit, and when it is determined that the image forming cartridge has the developer remaining after the image forming cartridge reaches the preliminary life value, the replenishment of the developer is suppressed. A notification is output to the output unit, and after that, when it is determined that there is no developer in the image forming cartridge, a request for replacing the image forming cartridge with a different output from the notification for suppressing the supply of the developer is output to the output unit. An electrophotographic printing device characterized by outputting.