JP2002258692A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus in which reliability during access to a nonvolatile memory is increased. SOLUTION: The image forming apparatus in which a cartridge 2 having a nonvolatile memory 6 to store at least operating condition information can be attached to and detached from a main body 1, is provided with a control board 5 which writes operating condition information in the nonvolatile memory 6 by serial data transmission at timing other than at image forming operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine and a laser printer, and more particularly, to an image forming apparatus in which a cartridge having a nonvolatile memory capable of storing at least usage status information can be detachably attached to a main body.

[0002]

2. Description of the Related Art In an image forming apparatus having an electrophotographic process, a photosensitive member and its surroundings are charged, developed, transferred, and transferred.
2. Description of the Related Art It is widely practiced to form a process cartridge by integrating a part or all of an electrophotographic process such as cleaning, and to remove and replace a process cartridge from an image forming apparatus main body depending on a service life.

Conventionally, this process cartridge has been disposable, but the number of recyclable ones has increased from the viewpoint of environmental protection and ecology. However, JP-A-9-11
As shown in Japanese Patent No. 4334, in many cases, only the contents (for example, toner) of a cartridge are replaced and the cartridge itself (mechanical parts) is reused. For this reason, there is a possibility that the mechanical parts may be damaged, which may endanger the image forming apparatus.

[0004]

Therefore, there has been proposed an image forming apparatus in which the use state and the like are stored as cartridge information and control is performed based on the information. If data is written to the nonvolatile memory by serial communication (serial bus), the cost becomes low.

[0005] However, when the cartridge portion is disposed near the application of a high voltage, which is peculiar to paper conveyance or an electrophotographic process, serial communication may not normally operate due to static electricity.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus capable of improving reliability when accessing a nonvolatile memory.

[0007]

According to one aspect of the present invention, there is provided an image forming apparatus in which a cartridge having a nonvolatile memory capable of storing at least usage status information is detachably mountable to a main body. The present invention relates to an image forming apparatus including a control board for writing usage status information to a nonvolatile memory by serial data transfer at a timing other than the forming operation.

According to a second aspect of the present invention, when the access to the nonvolatile memory becomes impossible, the control board executes the retry at a timing other than the image forming operation. The present invention relates to a forming apparatus.

According to a third aspect of the present invention, a nonvolatile memory is provided on the control board, and when the nonvolatile memory on the cartridge side cannot be accessed, the control board is
2. The image forming apparatus according to claim 1, wherein the manufacturing information is logged in a non-volatile memory of the apparatus, and when an error of the same manufacturing information occurs a predetermined number of times, the cartridge is disabled.

According to the first aspect of the invention, reliability is improved by performing communication at a timing other than the image forming operation to which the high voltage is not applied.

According to the second aspect of the present invention, the reliability is improved by limiting the timing only when an error occurs while performing real-time writing.

According to the third aspect of the present invention, information for eliminating the cause of the malfunction is provided to the user (because the user is notified that the cartridge cannot be used).

[0013]

Embodiments of the present invention will be described below with reference to the drawings. First, the invention according to claim 1 will be described. FIG. 1 is a block diagram of the image forming apparatus according to the first embodiment. The image forming apparatus includes a main body 1 and a cartridge 2. The main body 1 has a main power supply 3 for converting AC to DC, and uses a DC power supply for an electrophotographic process.
A high-voltage power supply that outputs a high-voltage power supply such as a charging high-voltage power supply, a developing high-voltage power supply, and a transfer high-voltage power supply (there are other high-voltage power supplies for paper separation and grid high-voltage power supplies; 4 Further, it also has a control board 5 for controlling printing and controlling the high-voltage power supply 4. The cartridge 2 has a non-volatile memory 6 for storing usage status information and the like in addition to well-known components for the electrophotographic process.

Normally, when an image forming operation such as a printing operation is performed, the control to the high-voltage power supply 4 is performed from the control board 5. Performing serial data transfer to the same unit (cartridge 2) physically in that state has a high possibility that noise will be mixed into data lines and clock lines, and correct data cannot be written to the nonvolatile memory 6 (or read out). Can not be issued).

FIG. 2 is a timing chart showing a state where noise overlaps the clock line. Originally, data AAh was to be written to the nonvolatile memory 6 as transfer data. However, since noise was added after the third clock, the data is changed to data A6h. There are various methods for reducing noise in terms of hardware. However, in order to increase the cost of the apparatus, the present invention accesses the nonvolatile memory 6 when the high-voltage power supply control is not performed.

FIG. 3 is a flowchart of the first control example. First, if there is data to be updated, the data is stored in the latest update buffer (S1, S2). next,
The contents of the previous write buffer and the contents of the latest update buffer are compared (S3), and if different, it is determined that it is necessary to write to the nonvolatile memory 6. Therefore, it is determined whether or not the high voltage power supply is being controlled (S4). If the control is not being performed, data is written by actually performing serial communication (S5), and the contents of the previous write buffer are updated. In this way, the influence of noise can be suppressed.

Next, the second aspect of the present invention will be described. FIG.
In the case where a communication error can be detected by hardware in the case where noise as shown in (1) appears, rewriting is performed to maintain the real-time property of data retention. However, the timing of the retry at the time of occurrence of the error is after the high-voltage power supply control to improve the reliability of data communication.

FIG. 4 is a flowchart of the second control example. As described above, the same processing as in the first control example is performed in S1 to S3, and then data is written to the nonvolatile memory 6 (S4). Here, it is determined that a communication error has occurred (S
5) If no error occurs, the latest data buffer value is assigned to the previous write buffer (S6). If no error has occurred and the high-voltage power supply is not being controlled (N in S7), the communication error is canceled (S8).

Next, the invention according to claim 3 will be described. FIG.
FIG. 3 is a block diagram of an image forming apparatus according to a second embodiment. 1 in that a second nonvolatile memory 7 [nonvolatile memory (2)] is provided on the control board 5.

FIG. 6 is a flowchart of a third control example, and FIG.
(1) to (5) are diagrams showing examples of the internal data format of the second nonvolatile memory. To simplify the description, it is assumed that the serial number and the error in the manufacturing information cannot be used three times. The cartridge No. currently in the apparatus is 10002 shown in (2) of FIG. According to the flow of FIG. 6, if the cartridge 2 is not replaced, the usage status is updated.
This is the same as the above invention (S1 to S7). Cartridge 2
Has been exchanged and serial No.1 that has never been used before
Assume that 0028 has been entered. The cartridge information (error count) currently used is stored in the corresponding location, and 1
The cartridge information 0028 is newly stored (fourth in the example). Then, the cartridge information currently used is set to 10028. Then, the usage status is checked ((3) in FIG. 7).

Next, it is assumed that the cartridge 2 has been replaced with 10001 [(4) in FIG. 7]. So 10028
Error information (remains 0 in this example) and 10
001 is read out and registered as cartridge information currently used (two times of errors).
12. Thereafter, when the device is used and an error occurs, the number of errors is increased from 2 to 3 (S13), and an error warning is displayed (S14, S15). FIG. 7 (5) shows the contents of the nonvolatile memory (2) at that time.

[0022]

According to the first aspect of the present invention, reliability can be improved by performing communication at a timing other than the image forming operation to which the high voltage is not applied.

According to the second aspect of the present invention, the reliability can be improved by limiting the timing only when an error occurs while performing real-time writing.

According to the third aspect of the present invention, it is possible to provide the user with information for eliminating the cause of the problem.

[Brief description of the drawings]

FIG. 1 is a block diagram of an image forming apparatus according to a first embodiment.

FIG. 2 is a timing chart showing a state where noise overlaps a clock line.

FIG. 3 is a flowchart of a first control example.

FIG. 4 is a flowchart of a second control example.

FIG. 5 is a block diagram of an image forming apparatus according to a second embodiment.

FIG. 6 is a flowchart of a third control example.

FIG. 7 is a diagram showing an example of an internal data type of a second nonvolatile memory.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Cartridge 3 Power supply 4 High voltage power supply 5 Control board 6 Non-volatile memory

Claims (3)

[Claims] In an image forming apparatus in which a cartridge having a nonvolatile memory capable of storing at least usage status information is detachably attached to a main body, serial data transfer is used to transfer the usage status information to the nonvolatile memory at a timing other than the image forming operation. An image forming apparatus comprising a control board for performing writing. 2. The control board according to claim 1, wherein when the access to the nonvolatile memory becomes impossible, the control board executes the retry at a timing other than the image forming operation.
The image forming apparatus as described in the above. 3. The control board has a non-volatile memory, and when the non-volatile memory on the cartridge side cannot be accessed, the control board causes the non-volatile memory on the apparatus side to log manufacturing information, and an error of the same manufacturing information is made. 2. The image forming apparatus according to claim 1, wherein when the predetermined number of times has occurred, the cartridge is made unusable.