JPH06118736A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To provide an electrophotographic device for enhancing the precision of the life control of a unit by making the discrimination of newness/oldness easy and simple. CONSTITUTION:The electrophotographic device is provided with the process cartridge 4 of the unit which has finite service duration and can be exchanged, a device main body 2 to/from which the unit is attached/detached as necessary, the installation of the fuse 6 of a electronic device broken down by the supply of power from a device main body side, on a unit side and a decision control circuit 8 as a new/old deciding means deciding whether the fitted unit is a new or used one by the breakdown of the electronic device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus using a replaceable unit such as a process cartridge which has a limited usage period.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic apparatus such as a laser printer, a main body apparatus can be used for a long period of time.
The main body device is configured as a replaceable unit by distinguishing the consumable parts, and the life of the unit side is managed to prevent failures and maintain image quality. Consumable parts in this electrophotographic apparatus include, for example, OPC.
There is a photosensitive drum having an (organic photo conductor: organic photoconductor) on its surface, and a unit in which a developing device, a toner supplying device, and the like are integrated with the photosensitive drum. Such a unit is known as a process cartridge.

The life management of this unit is performed by means for measuring the operation amount of the unit mounted on the apparatus main body side. That is, the measuring means is reset when the unit is attached to the main body device, and counting is performed for each predetermined operation amount. The time when the count value reaches a predetermined count value is determined as the life period, and the user is notified of the end of the life by the notification means. Therefore, the user can know the end of life of the unit by the notification and replace the unit.

[0004]

By the way, in the electrophotographic apparatus which manages the life as described above, attachment / detachment of the unit to / from the main body device impairs the life determination on the side of the main body of the apparatus. For example, if the unit is removed and then reattached for paper jams or repairs, the count value is reset, and correct life judgment cannot be performed. That is, when the unit is attached or detached during its life, the unit in use is regarded as a new unit. Also, if the count value is held indiscriminately, when the new unit is replaced, the previous count value is inherited, which is inconvenient.

Therefore, Japanese Patent Publication No. 4-19548, "Image Forming Apparatus" has been proposed as a method for making a correct life judgment by determining old and new. In this image forming apparatus, an identification code is provided on the unit, and each time the unit is mounted on the main body apparatus side, it is determined whether the unit is new or old, and the operation amount is measured and managed.

However, such an identification code requires a complicated structure for determining whether it is old or new.
That is, a means for reading the identification code, a storage means for the newly read identification code, etc. are required, which is inconvenient for managing the unit having replaceability as a consumable item because the equipment is complicated and the cost is increased.

Therefore, an object of the present invention is to provide an electrophotographic apparatus in which the accuracy of life management of a unit is improved by facilitating and simplifying the discrimination between old and new.

[0008]

As shown in FIG. 1, an electrophotographic apparatus according to the present invention includes a unit (process cartridge 4) which can be exchanged for a limited period of time, and this unit can be attached and detached as required. A main body (2) of the device, and an electronic element (fuse 6 or diode 26) which is destroyed by electricity from the main body of the device on the unit side,
It is characterized in that it comprises an old / new judgment means (judgment control circuit 8) for judging the old / old of the mounted unit by breaking the electronic element.

Further, in the electrophotographic apparatus of the present invention, the old and new judging means includes a unit (process cartridge 4) which has a finite period of use and is replaceable, and an apparatus main body (2) to which the unit is detached as required. And an electronic element (fuse 6
Alternatively, a diode 26), an energizing means (transistor 16) for energizing the device body to destroy the electronic element when the unit is mounted, and the electronic element when the unit is mounted to the device body. And a detection unit (input buffer 22) for detecting the presence or absence of destruction of the.

[0010]

In this electrophotographic apparatus, a unit whose use period is limited with respect to the apparatus main body is exchanged if necessary. Therefore, in the present invention, a destructible electronic element is attached to the unit side having exchangeability, the electronic element is destroyed when the unit is attached to the apparatus main body side, and even if the unit is detached, the electronic element is detached. The judgment principle is to judge whether the unit is old or new by destroying the unit.

The old and new judging means is provided with energizing means for energizing the unit on the apparatus main body side, and an overcurrent is caused to flow to the electronic element on the unit. When the electronic element is destroyed by this overcurrent, that is, when the state of disconnection occurs,
That unit becomes an old unit. That is, when the unit is attached to the apparatus body after attachment / detachment, the disconnection state of the electronic element is detected. Based on the detection, the new / old determination means determines that the mounted unit is a conventional unit, and inherits the count value of the usage amount and continues counting. Therefore, the accuracy of the life judgment of the unit whose use period is finite can be improved.

A fuse or a diode can be used as the electronic element which can be destroyed by energization.
The fuse and the diode are easily destroyed by energization, and it is possible to improve the determination accuracy of the old and new units.

[0013]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

FIG. 1 shows an embodiment of an electrophotographic apparatus showing an embodiment of the present invention. An apparatus main body 2 of this electrophotographic apparatus has a main body mechanism for performing a printing operation using an electrophotographic process, and a process cartridge 4 as a unit having a finite period of use on the front surface thereof.
Is detachably provided as indicated by an arrow A. The process cartridge 4 integrally includes a photosensitive drum, a developing device, and a toner supplying device. The process cartridge 4 is provided with a switch (not shown) as a means for detecting attachment / detachment to / from the apparatus main body 2. The above-mentioned configuration is the same as that of various electrophotographic apparatuses such as the conventional image forming apparatus, so detailed description thereof will be omitted. A fuse 6 is installed on the front surface of the process cartridge 4 as an electronic element forming a part of the old / new determination means.

Next, FIG. 2 shows a life judging system in the electrophotographic apparatus. That is, the process cartridge 4
A fuse 6 is installed on the side as an electronic element that can be destroyed by an overcurrent, and connectors 10 and 12 are provided as connection means for connecting to the determination control circuit 8 side as old and new determination means on the apparatus body 2 side. Has been. The fuse 6 is connected between the connectors 10 and 12.

A power source + V for energizing the fuse 6 on the side of the process cartridge 4 mounted on the apparatus main body 2 is provided on the side of the judgment control circuit 8 and the fuse is connected via the connectors 10 and 12. A resistor 14 and a transistor 16 are installed as a means for energizing the fuse 6 together with the power source + V in a series circuit with the resistor 6. A central processing unit (CPU) 20 as a control means is connected to the base of the transistor 16 via a resistor 18, and when the fuse 6 is not blown, a base current for conducting the transistor 16 is applied.

Further, an input buffer 22 is connected between the connector 12 and the CPU 20 as a detection means for taking in a potential input to the CPU 20 side as a detection signal based on whether the fuse 6 is blown or not blown.

A non-volatile memory 24 is connected to the CPU 20 as a storage means for accumulating the count value representing the data in use and the amount of use. A backup power supply 25 such as a battery is connected to the non-volatile memory 24 to back up the stored contents.

In the above construction, when the power is turned on or when the process cartridge 4 is exchanged, it is judged whether the process cartridge 4 mounted is old or new. When the power is turned on or the process cartridge 4 is replaced, the mounting of the process cartridge 4 in the apparatus main body 2 is confirmed, and then the CPU 2
0 reads the output signal from the input buffer 22. In this case, if the fuse 6 is not blown, the control power supply + V and the input buffer 22 are connected, and the output of the input buffer 22 becomes L (low) level. Based on this L level, the process cartridge 4 is determined to be new. On the other hand, if the fuse 6 is blown, the ground level and the input buffer 22 are connected via the resistor 14, so that the level of the output signal of the input buffer 22 becomes H (high) level. At this time, it is determined that the process cartridge 4 is not new.

In this way, the CPU 20 can determine the old or new of the process cartridge 4 from the output signal from the input buffer 22 based on the detection of whether or not the fuse 6 is blown. Further, as described in the conventional example, the CPU 20 counts for each operation amount of the process cartridge 4, for example, for each number of printed sheets, and the count value is stored in the nonvolatile memory 24 and held as life information. .

Next, FIG. 3 shows a processing program in the CPU 20. That is, in step S1, it is determined whether or not the fuse 6 is blown. If it is determined that the fuse 6 is not blown (NO), the process cartridge 4 is a new one, so the process proceeds to step S2 and measurement is performed. The means is reset, and then the process goes to step S3 to blow the fuse 6. As a result, the CPU 20 will not erroneously determine that the process cartridge 4 is new even if the process cartridge 4 is remounted. The situation in which the process cartridge 4 is re-mounted occurs after the user removes the process cartridge 4 because the paper remains in the machine for some reason during the printing operation of the apparatus main body 2.

Then, the fuse 6 in step S3
The fusing is performed by causing the transistor 16 which has received the output from the CPU 20 at the base to conduct, and thereby causing an overcurrent to flow through the fuse 6 through the transistor 16.

Next, FIG. 4 shows details of step S3 for blowing the fuse 6. That is, in step S31, 0 is written in the memory counter i which is used as a counter by using the memory. Next, in step S32, it is confirmed whether or not the fuse 6 is blown. Fuse 6
If the value of the memory counter i is not 3 or more, it is checked whether the value of the memory counter i is 3 or more. Then, in step S34, the energization time is, for example, 200 ms.
ec is energized. This energization process is performed by the transistor 16
Is conducted by conducting.

Next, in step S35, the value of the memory counter i is incremented by 1, and the process returns to step S32. When the fuse 6 is blown, the process exits this subroutine and returns to the higher-level flow of step S36.

When the fuse 6 is not blown even after the energization of 200 msec for the energization time of 200 msec, the number of times of the energization is determined in step S33, the process proceeds to step S37, and an error process is performed assuming that there is some abnormality. .
This error processing is, for example, stopping of various energization states and error display.

Therefore, in this electrophotographic apparatus, when the fuse 6 does not blow even when a predetermined current is applied,
Since the control is made so as to determine the abnormality, it is possible to avoid a dangerous situation such as continuing to energize the fuse 6, and it is possible to realize a safe device.

With the above control, the print operation is continued,
The count of the number of printed sheets or the like is increased for each operation amount, but when it is determined that the count value has reached the specified life value as in the conventional example, the CPU 20 notifies the user of the end of the life by a display panel or the like. be able to.

Next, FIGS. 5A and 5B show the second connection of the fuse 6 on the process cartridge 4 side.
The example of is shown. That is, when it is necessary to identify a plurality of process cartridges 4, for example, a red toner-containing process cartridge 41 for performing red printing and a black toner-containing process cartridge 4 for performing black printing.
When it is desired to distinguish between the fuse 2 and the fuse 2, it is achieved by providing a plurality of sets of control circuits for identifying the fuse 6 and its blown or non-blown, for example, two sets for the discrimination of the red and black process cartridges 41 and 42.

To explain this in detail, as shown in FIGS. 5A and 5B, the fuse 61 and the fuse 62 perform the same function as in the first embodiment, and each process cartridge 4 is new. It is used to determine whether or not.

The fuse 63 is blown immediately after the red toner-containing process cartridge is determined to be new. On the other hand, the resistor 7 is subjected to fusing control immediately after the black toner-containing process cartridge is determined to be new,
It does not melt. Therefore, the fuse 63 and the resistor 7
Therefore, it is possible to distinguish between the red toner and the black toner. That is, by installing a plurality of fuses 61 and 63 in the process cartridge 41, the process cartridge 41 is distinguished from the process cartridge 42.

Next, FIG. 6 shows a third embodiment of the process cartridge 4. That is, up to seven process cartridges 4 can be used in parallel at the same time, and the process cartridge 43 has three fuses 64, 65, 6 connected in parallel to one power supply terminal 70.
6 is built in. The fuses 64 and 6 are provided on the device body side.
A control circuit for identifying blowout and non-blowing corresponding to each of Nos. 5 and 66, and a blowout means for blowing out any fuses 64, 65, 66 are provided. When none of the fuses 64, 65, 66 of the set process cartridge is blown, it is determined that the cartridge is a new cartridge, and the fuse 6
4 is melted and counting is started in the count area provided for the first cartridge. Next, when a new cartridge is used, the fuse 65 is blown, a new count area is secured for the second cartridge, and counting is started. The seven process cartridges can be individually managed by the combination (= 7 types) of the blown states of the fuses 64 to 66.

The fuses 6, 61, 62, 63, 6
4, 65 and 66 are, as shown in this embodiment, the fusing function,
That is, it may be a so-called fuse resistor, that is, one having both a function as a resistance and a function as a fuse, as long as it has a function of fusing by overcurrent.

FIG. 7 shows the fourth embodiment of the process cartridge 4. The fuse 6 of the above-described embodiment may be configured with the diode 26. Even when the diode 26 is used, the same effect as in the above embodiment can be obtained.

The fuses 6 to 66 and the diode 26 are also included.
In addition to being fixedly installed in the process cartridge 4, it may be mechanically detachable for recycling the process cartridge 4.

Since the present invention enables the old and new of a replaceable unit to be identified and the unit to be identified, the replaceable unit is not limited to the process cartridge 4 of the embodiment. Needless to say, the present invention can be applied to a so-called toner cartridge having a built-in and supplying function, and can be used for detecting the remaining amount of toner.

[0036]

As described above, according to the present invention,
The following effects are obtained. a. It is possible to identify whether the unit is new or re-installed by a simple judgment as to whether or not the electronic element equipped in the replaceable unit is broken, so that the operation amount of the unit can be accurately counted and the correct operation can be performed. It becomes possible to judge the life.

B. The unit can be easily identified by using a plurality of sets of electronic elements and control circuits, and the conventional identification code and the complicated circuit for discriminating the identification code are unnecessary, resulting in a significant cost reduction.

C. By using an inexpensive fuse or diode for the unit, the running cost of the unit to be replaced can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an electrophotographic apparatus of the present invention.

FIG. 2 is a circuit diagram showing a determination control system in the electrophotographic apparatus of the present invention.

FIG. 3 is a flow chart showing unit old / old determination in the electrophotographic apparatus of the present invention.

FIG. 4 is a flowchart showing details of step S3 of the flowchart shown in FIG.

FIG. 5 is a circuit diagram showing a second embodiment of the fuse connection structure in the process cartridge.

FIG. 6 is a circuit diagram showing a third embodiment of the fuse connection structure in the process cartridge.

FIG. 7 is a circuit diagram showing a process cartridge in which a diode, which is a modification of a destructible electronic element, is installed.

[Explanation of symbols]

 2 Device main body 4 Process cartridge (unit) 6 Fuse (electronic element) 8 Judgment control circuit (new / old judgment means) 16 Transistor (energizing means) 22 Input buffer (detection means) 26 Diode (electronic element)

Claims (4)

[Claims] 1. A replaceable unit having a finite period of use, an apparatus main body to which this unit is attached and detached as needed, and an electronic element which is destroyed by electricity from the apparatus main body side on the unit side, An electrophotographic apparatus comprising: an old / new judging unit for judging the old / old of a mounted unit by breaking the electronic element. 2. The old and new judging means includes an electronic element which is provided in the unit and is destroyed by energization, and an energizing means which is energized to destroy the electronic element when the unit is attached to the apparatus main body. An electrophotographic apparatus, comprising: a detection unit that detects whether or not the electronic element is broken when the unit is attached to the apparatus main body. 3. The electrophotographic apparatus according to claim 2, wherein a fuse is used for the electronic element. 4. The electrophotographic apparatus according to claim 2, wherein a diode is used as the electronic element.