JP2754102B2 - Electrophotographic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus used for a laser beam printer, a copying machine, etc., and an improvement of a notifying means for notifying the number of times of image formation executed by the apparatus to facilitate maintenance and the like. About.

[0002]

2. Description of the Related Art In an electrophotographic apparatus, an electrostatic latent image formed by exposing a charged photoreceptor to light is developed with a developer such as toner, and the toner image is transferred to a recording medium to form an image on the recording medium. To form. The photoreceptor is deteriorated by repeated exposure to the photosensitive material constituting the photoreceptor or by contact with ozone generated by the discharge of a discharger used for charging. If the image is handled and deteriorated due to deterioration, the image needs to be replaced.

Therefore, in a conventional printer utilizing electrophotography, attention is paid to the number of recording media printed as information on the life of the photosensitive member, and the number of printed sheets is counted by a sheet counter using a nonvolatile storage element. When the count value reaches a predetermined value, this is detected and displayed to that effect, so as to notify the user to replace the photosensitive member (see Japanese Patent Application Laid-Open No. 62-75468).

The counter is replaced with a new one at the same time that the photosensitive member is replaced. The counter is set to an initial value every time the photosensitive member is replaced. Can not count the total number of printed sheets from the start of use of the electrophotographic device,
Components other than the photoconductor of the electrophotographic apparatus, for example, a charging unit,
In order to manage the time of maintenance work and the like of the developing device, the transfer section, the static elimination section, and the like that can be used for a relatively long period of time, a mechanical counter for counting the total number of printed sheets is provided separately from the number counter. Was provided.

[0005]

However, since the mechanical counter is generally provided in a hardly visible place inside the main body of the apparatus, it is easy to overlook that the maintenance target component has reached the end of its service life. It was easy to invite. Further, since the mechanical counter is expensive, there has been a problem in terms of price.

In view of the problems of the prior art, the present invention records the total number of image formations from the start of use of the apparatus using an inexpensive nonvolatile storage element without using an expensive mechanical counter. And to be able to notify the number of times.

[0007]

An electrophotographic apparatus according to the present invention forms an electrostatic latent image on a photoreceptor, and records the electrostatic latent image by transferring a toner image developed with a developer onto a recording medium. In an electrophotographic apparatus for forming an image on a medium, a first counter detachably provided in the apparatus main body and configured by a nonvolatile storage element and updating a count value of image formation each time an image is formed; A non-volatile storage element having a second counter for updating a count value when it is detected that the counter is in an initial state, and storing a first predetermined value and a second predetermined value; and the second counter Calculating means for calculating the total number of printed sheets from the counted value of the first and second predetermined values and the image forming count data of the first counter; and when the first counter is equal to or more than the first predetermined value, and The calculating means Calculation result by is that a notifying means for warning if more than the second predetermined value.

[0008]

In the electrophotographic apparatus of the present invention having such a configuration, the nonvolatile memory element which is detachably provided on the apparatus body.
Based on the count value of the first counter composed of
It is reported that the number of image formation of the photoconductor in use has reached a predetermined value.
And a non-volatile memory having a second counter.
Calculate the total number of printed sheets from the value counted and stored by the storage element.
The maintenance time for parts other than the photoconductor based on the calculation results.
I can inform you.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a configuration diagram showing an arrangement of respective components of a laser beam printer using an electrophotographic apparatus. A photosensitive drum 2 (photoreceptor) is arranged at a substantially central portion in a housing 1. The photosensitive drum 2 is driven to rotate in one direction by a drive motor 3, that is, clockwise in the drawing, and the surface of the photosensitive drum 2 is uniformly charged around the photosensitive drum 2 according to an electrophotographic process. A charging unit 4 irradiates a laser beam controlled by information to the photosensitive drum 2 uniformly charged by the charging unit 4 to remove electricity according to the information, thereby forming an electrostatic latent image on the surface of the photosensitive drum 2. Exposure section 5 to be formed, and toner 6 as a developer is applied to the electrostatic latent image on the surface of photosensitive drum 2 formed by exposure at exposure section 5.
, A developing unit 7 for transferring the toner image of the photosensitive drum 2 to a paper 8 (recording medium) to be conveyed, and a cleaning unit 10 for removing residual toner from the surface of the photosensitive drum 2 A charge removing section 11 for removing charges remaining on the surface of the photosensitive drum 2 is sequentially arranged in the rotating direction of the photosensitive drum.

The transfer section 9 is located below the photosensitive drum 2,
The sheet 8 is sent out one by one by the operation of the pickup roller 13 in response to a sheet supply instruction from a sheet supply cassette 12 provided on one side of the housing 1 toward the transfer unit 9, and the transfer rollers 14, 14 are provided. Are transported along the transport path 15.

After the toner image on the photosensitive drum 2 is transferred by the transfer unit 9 to the conveyed sheet 8, the sheet 8 is fixed by the fixing unit 16 and is discharged to the upper side of the housing 1 by the discharge rollers 17. It has become.

The housing 1 includes an upper housing 1a and a lower housing 1b. The photosensitive drum 2 of each of the constituent members includes a charging unit 4, a developing unit 7, a cleaning unit 10,
At least one of the static elimination units 11 is integrally incorporated via a support member of the photosensitive drum 2, and is attached to the lower housing 1b together with the photosensitive drum 2 so as to be easily detachable. As for other components, components arranged above the transport path 15 for the paper 8 are incorporated in the upper housing 1a, and components arranged below are incorporated in the lower housing 1b.

The upper housing 1a is connected to a lower housing 1b.
By opening the upper housing 1a, the photosensitive drum 2 can be detached from the lower housing 1b together with the components integrally formed with the photosensitive drum 2 by opening the upper housing 1a. , So that the transport path 15 for the sheet 8 is opened. A memory card (first counter), which will be described later, is detachably provided in a part of the lower housing 1b which is opened when the upper housing 1a is opened, and the upper housing 1a of the lower housing 1b is further provided. A cover open switch 18 for detecting the open / closed state of the upper housing 1a is provided at a position where the upper housing 1a comes into contact with or separates from the main body 1a.

The charging unit 4, the exposing unit 5, the developing unit 7, the transferring unit 9, the cleaning unit 10, the neutralizing unit 11, and the fixing unit 16
Are the number of sheets that can be printed by one photosensitive drum 2 (about 100
When the number of printed sheets (about 80,000 sheets) is larger than (00 sheets), the member is a maintenance target member requiring replacement or maintenance work.

FIG. 1 is a block diagram showing an electric hardware configuration of the printer. A central processing unit (CPU) 20 constituting a control unit main body has a lead line in which program data and the like are stored in advance via a bus line 21. · Only memory (ROM) 22, random access memory (RAM) 23 in which a print buffer for expanding print data as image data is formed, and an electrically erasable programmable memory for storing various set values unique to the printer. ROM (EEPR
OM, non-volatile storage element) 24, a memory card 25 as a first counter which is detachably mounted so as to be exchangeable when exchanging the photosensitive drum 2 and is constituted by a non-volatile storage element for storing the number of times of image formation. A card interface 26 for reading and writing data, a transmission interface 27 for transmitting and receiving data to and from a host device (not shown), and an I / O port 28 are connected to each other. The calculating means is controlled by the CPU 20 and the ROM 22.
It is configured.

The I / O port 28 includes a liquid crystal display 29 for displaying various messages, a buzzer 30 for notifying the exchange of the photosensitive drum 2, a high-voltage power supply circuit 31 for supplying a high voltage to the charging unit 4 and the transfer unit 9. A motor drive circuit 32 for controlling the drive of the drive motor 3, an operation command key 33a for inputting a notification command for giving a command for displaying the total number of printed sheets, and an operation unit 33 including a key for giving various instructions, and a cover open switch 18 and the like are connected.

The memory card 25 is for storing a count value N1 of the number of prints (the number of times of image formation) as information on the life of the photosensitive drum 2, and is a replacement part set with the photosensitive drum 2. When the photosensitive drum 2 is replaced, the memory card 25 is also replaced.

The reason why the memory card 25 is exchanged together with the photosensitive drum 2 is to detect the exchange of the memory card 25 and to judge that the photosensitive drum 2 has been exchanged by detecting the exchange of the memory card 25 as described later. Inexpensive E
EPROMs have a low number of guaranteed writes (typically 10
If the counter is used as a counter, the total number of printable sheets of the photosensitive drum 2 exceeding the number of printable sheets of one photosensitive drum 2 is counted and counted. Since the count value does not guarantee the reliability, it cannot be used as a count counter that normally exceeds 10,000 times. If the count is 10,000 times, replace it with a new one that guarantees 10,000 new writes. As described above, conventionally, a mechanical counter has been used to know the total number of printed sheets since the start of use of the printer.
Because the number of guaranteed write times is small, simply trying to count the number of prints using an EEPROM
It is conceivable that the total number of prints at M is counted up to the number of guaranteed prints at the time of counting 10,000 sheets, and the count value of the number of printed sheets becomes unreliable.

The EEPROM 24 stores various set values of the apparatus main body. The number of replacements of the photosensitive drum 2 is stored as the number of replacements n of the memory card 25. And a photoreceptor limit sheet number storage section 24b as a first predetermined value for storing a photoreceptor limit value A, and a sheet number value B indicating that when the total number of printed sheets reaches this number is a maintenance work time.
Is stored as a second predetermined value for storing the maintenance time printed sheet number storage section 24c, and the sheet number value B1 for updating the sheet number value B of the maintenance time printed sheet number storage section 24c to the sheet number value indicating the next maintenance time. The required maintenance print number storage section 24d is formed.

Next, the control of the printer will be described with reference to a flowchart (FIG. 3) showing the control when the power is turned on.

That is, when the power is turned on, predetermined initial processing is performed (ST100), and then the storage data of the memory card 25 mounted, that is, the number of prints N1 is read via the card interface 26 (ST10).
1). Then, it is determined whether the number of prints N1 is "0" (ST
102), if N1 is not 0 (greater than "0"), it is not immediately after the replacement of the photosensitive drum 2, so that the use condition of the photosensitive drum 2 is set to the preset use limit number of photosensitive members. A comparison is made with the corresponding predetermined value A (for example, 10,000 sheets) (ST103). At this time, if the number of prints N1 is equal to or more than the usable number of photosensitive drums 2, the liquid crystal display 29 indicates that it is time to replace the photosensitive drums 2, and the buzzer 30 sounds a message to the user. (ST104). This ST101, ST10
2. ST103, ST104, the liquid crystal display 30 and the buzzer 31 constitute a notification means.

On the other hand, the number of prints N1 is
If the number is smaller than the use limit number A, it is not time to replace the photosensitive drum 2 and the process proceeds to the printing process (ST112).

If the number of prints N1 is "0" in ST102, it is determined that the photosensitive drum 2 and the memory card 25 have been replaced with new ones, and the data stored in the replacement number storage unit 24a, that is, the photosensitive drum performed after the previous maintenance work, is determined. The number of replacements n of the drum 2 is read out (ST105), and the total number of printed sheets N2 is calculated based on the number of replacements n and the predetermined value A (ST105).
106). This relationship is represented by the following equation (1).

[0024]

N1 = n × A (1)

Then, "1" is added to the storage data n of the number-of-times-of-replacement storage unit 24a (ST107) to update the storage data.
1 is set to "1", and processing is performed to the effect that the number of replacements has been counted for this memory card 25 (ST108).

Next, the calculation result N2 in ST106 is compared with a predetermined value B stored in the maintenance time printed sheet number storage section 24c (ST109). If N2 ≧ B, it is determined that the maintenance time is reached. The image is displayed on the liquid crystal display 29 and the buzzer 30 is driven (ST110).

At this time, the maintenance time print number storage unit 24
A predetermined value B1 stored in the maintenance required print number storage unit 24d is added to the predetermined value B of c, and the maintenance time print number storage unit 24 is added.
The predetermined value B of c is updated to the number of printed sheets at the maintenance time indicating the next maintenance time (ST111). This “B1” is the number of prints that can be made between the maintenance work and the next maintenance work.
That is, when printing is performed for the number of prints B1, this is a number corresponding to the number of prints requiring the next maintenance operation.
By adding 1, the predetermined value B in the maintenance time print number storage section 24c is updated to the next print time when the total print number N2 reaches B next time.

Thus, the user knows that the maintenance of the components is necessary in addition to the replacement of the photosensitive drum 2, and can request maintenance work. In addition, (ST10
If the total number of prints N2 has not reached the predetermined value B in 9), the process proceeds to the printing process (ST112).

Next, in the printing process shown in FIG. 4, the transmission interface 27 is checked to determine whether or not print data has been received (ST200). If the print data has been received, the storage data of the memory card 25 inserted through the card interface 26, that is, the number of prints N1 is read (ST20).
1). Then, a printing process is executed based on the print data (ST202), and a value obtained by adding "1" to the number of prints N1 is written to the memory card 25 as the current number of prints N1, and the number of prints N1 is updated (ST203). .

If no print data has been received in ST200, it is determined whether an instruction to display the total number of printed sheets has been issued, that is, whether a notification command has been input (ST204). Card interface 26
, The number of prints N1 is read out (ST205), and the number of replacements n of the photosensitive drum 2 is read out from the number of replacements storage unit 24a (ST206) to calculate the total number of prints N2. (ST2
07), the count value N2 is displayed on the liquid crystal display 29 (ST208). The relationship between the total number of printed sheets N2 is given by the following equation (2).
Represented by

[0031]

N2 = n × A + N1 (2)

The above ST205, ST206, ST20
7, ST208 and the liquid crystal display 29 constitute display means.

If neither the print data reception nor the notification command is input, other processing is executed (ST20).
9). This printing process is repeatedly executed.

In the printing process, the state of the cover open switch 18 for detecting the open / closed state of the housing 1a is detected at each step as appropriate. If cover open is detected, FIG. The processing of the flowchart shown is executed.

First, for example, a cover open process for turning off the heater of the fixing device 16 or notifying the host device that the cover is being opened is executed (ST3).
00), waits for the upper housing 1a to be closed, that is, detects the state of the cover open switch 18 and
It waits for the detection of the close (ST301). And
When the cover close is detected, the cover close process, for example, notification to the effect that the cover open state has been canceled is executed to the host device (ST302), and the process shifts to the execution of the above-mentioned power-on process after ST101. .

When the cover open is detected, the processing after ST101 is performed when the cover is closed thereafter. Therefore, even if the memory card 25 is replaced while the power is turned on, the replacement is always detected. You can do it.

As described above, according to the present embodiment, if the photosensitive drum 2 has performed printing of a predetermined number of prints and the time to replace the photosensitive drum 2 has been reached, it is only possible to notify that it is time to replace the photosensitive drum 2. In addition, the maintenance time can be notified each time for other maintenance target parts, and a part of the non-volatile storage element that stores various setting information without using a mechanical counter is replaced with the number-of-times-of-replacement storage unit 24a of the memory card 25.
By counting the number of replacements of the photosensitive drum 2 by using the function, the total number of prints from the start of use of the printer can be displayed as necessary, so that the total number of prints from the start of use can be easily known. .

The present invention is not limited to the above embodiment. For example, the notification command may be input from a host device, and the replacement of the photosensitive drum 2 may be performed on the memory card 2.
The mounting state of No. 5 may be detected, and in the case of no mounting, it may be determined that the replacement is necessary according to the detection of the mounting after waiting for the mounting to be detected. Further, in the above-described embodiment, the alarm sound of the buzzer 30 may be distinguished between when the photosensitive drum 2 in use reaches a predetermined number of printed sheets and when the maintenance time of other maintenance target parts comes. By doing so, the liquid crystal display 2
9 can be omitted. Further, the warning may be performed only by displaying the message on the liquid crystal display 29, and the warning sound by the buzzer 30 may be omitted.

Further, a predetermined value B for determining the maintenance time of the maintenance target component is provided for each maintenance target component (the number of replacements storage unit 2).
4a) may be provided so that different maintenance times can be reported for a plurality of maintenance parts.

[0040]

As described above in detail, according to the present invention, it is possible to replace the photosensitive member with a simple and inexpensive structure and to maintain the photosensitive member.
Easy notification of maintenance time for components
Electrophotographic equipment, especially for calculating the total number of printed sheets.
To be used as a counter.
Memory area required, and non-volatile storage elements
It is also possible to use inexpensive ones with a small number of guarantees
Wear.

[Brief description of the drawings]

FIG. 1 is an electrical hardware configuration diagram of a laser beam printer showing an embodiment of an electrophotographic apparatus of the present invention.

FIG. 2 is a configuration diagram showing an arrangement of each component of the laser beam printer shown in FIG.

FIG. 3 is a flowchart showing a process when the power is turned on in the laser beam printer shown in FIG. 1;

FIG. 4 is a flowchart showing a printing process in the laser beam printer shown in FIG.

FIG. 5 is a flowchart showing a process when a cover open is detected in the laser beam printer shown in FIG. 1;

[Explanation of symbols]

 2 Photosensitive Drum (Photosensitive Member) 24a Replacement Number Storage Unit (Second Counter) 25 Memory Card (First Counter) 29 Liquid Crystal Display 30 Buzzer

Claims (1)

(57) [Claims] An electrophotographic apparatus that forms an image on a recording medium by forming an electrostatic latent image on a photosensitive member and transferring a toner image obtained by developing the electrostatic latent image with a developer onto the recording medium, A first counter which is detachably provided in the apparatus main body and which is constituted by a nonvolatile storage element and updates a count value of image formation each time an image is formed; and a first counter for detecting that the first counter is in an initial state. A non-volatile storage element having a second counter for updating the count value and storing a first predetermined value and a second predetermined value; a count value of the second counter, the first predetermined value, and calculation means for calculating the total number of printed sheets from the number of times of image formation data of the first counter, if said first counter is the first predetermined value or more, our
And an informing means for giving an alarm when a result of calculation by the calculating means is equal to or more than a second predetermined value.