JP5622878B2 - Image forming apparatus and image forming apparatus control method - Google Patents

Description

  Embodiments described herein relate generally to an image forming apparatus using an I2C bus for an interface between a memory chip (IC chip) mounted on a toner cartridge and a CPU, and a control method for the image forming apparatus.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as an MFP (Multi-Function Peripherals), a small IC chip is mounted on a toner cartridge, information such as the remaining amount of toner is stored in a memory in the IC chip, and the remaining amount of toner is The information is read and the remaining amount of toner is displayed.

  By the way, when the toner cartridge is replaced, since the image forming apparatus main body is switched on, the power supply on the IC chip side is turned off so that the IC chip does not break down. However, when I2C (Inter-Integrated Circuit) is used for the interface between the IC chip and the CPU, there is a problem that the I2C bus hangs up when the power of the IC chip is turned off.

JP 2011-232737 A

  The problem to be solved by the invention is to provide an image forming apparatus and an image forming apparatus control method capable of preventing the I2C bus from hanging when the power supply of the memory chip is controlled when the toner cartridge is inserted or removed. There is.

An image forming apparatus according to an embodiment communicates with a detection element that detects opening and closing of a cover provided in a main body, a memory chip attached to a toner cartridge in the main body, and the memory chip via an I2C bus. acquires the information recorded on the chip, wherein when the oFF or oN control of the power of the memory chip during insertion and removal of the toner cartridge, CPU previous SL I2C bus is controlled so as not to start condition and a stop condition status When the CPU detects that the cover is opened by the detection element, the CPU determines that the toner cartridge is removed, and sequentially sends the serial clock (SCL) and serial data (SDA) of the I2C bus. Power off the memory chip. When the detection element detects that the cover is closed, it is determined that the toner cartridge is mounted, and the memory chip is turned on, and then the I2C bus serial data (SDA) and serial clock ( SCL) is sequentially turned on .

1 is a configuration diagram illustrating an image forming apparatus according to an embodiment. 1 is an external view of an image forming apparatus according to an embodiment. 1 is a block diagram illustrating a control system of an image forming apparatus according to an embodiment. The connection diagram of CPU and memory chip group in one Embodiment. Explanatory drawing which shows the basic operation | movement of an I2C bus. Explanatory drawing which shows the cause of the hang-up in an I2C bus. Explanatory drawing which shows the operation | movement of hangup prevention in one Embodiment. The flowchart which shows the operation | movement of hangup prevention in one Embodiment.

  Embodiments for carrying out the invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected about the same location.

(First embodiment)
FIG. 1 is a configuration diagram of an image forming apparatus according to an embodiment. In FIG. 1, an image forming apparatus 10 is, for example, an MFP (Multi-Function Peripherals), a printer, a copying machine, or the like, which is a multifunction peripheral. In the following description, an MFP will be described as an example. There is a document table on the upper part of the main body 11 of the MFP 10, and an automatic document feeder (ADF) 12 is provided on the document table so as to be opened and closed. An operation panel 13 is provided on the upper portion of the main body 11. The operation panel 13 includes an operation unit 14 composed of various keys and a touch panel type display unit 15.

  A scanner unit 16 is provided below the ADF 12 in the main body 11. The scanner unit 16 reads a document sent by the ADF 12 or a document placed on a document table and generates image data. Further, a printer unit 17 is provided at the center of the main body 11, and a plurality of cassettes 18 for storing various sizes of paper are provided at the bottom of the main body 11. The printer unit 17 includes a photosensitive drum, a laser, and the like. The printer unit 17 processes image data read by the scanner unit 16 or image data created by a PC (Personal Computer) or the like to fix an image on a sheet as a recording medium. . The paper on which the image is fixed by the printer unit 17 is discharged to the paper discharge unit 40.

  The printer unit 17 is, for example, a tandem color laser printer, and scans the photosensitive member with a laser beam from the laser exposure device 19 to generate an image. The printer unit 17 includes image forming units 20K, 20Y, 20M, and 20C for black (K), yellow (Y), magenta (M), and cyan (C). The image forming units 20K, 20Y, 20M, and 20C are arranged below the transfer belt 21 in parallel from upstream to downstream.

  Since the image forming units 20K, 20Y, 20M, and 20C have the same configuration, the image forming unit 20K will be described as a representative. The image forming unit 20K includes a photosensitive drum 22K, and a charging charger 23K, a developing device 24K, a transfer roller 25K, a cleaner 26K, and the like are disposed around the photosensitive drum 22K. A toner cartridge 28 that supplies toner to the developing devices 24K, 24Y, 24M, and 24C is provided above the image forming units 20K, 20Y, 20M, and 20C. The toner cartridge 28 is adjacent to toner cartridges 28K, 28Y, 28M, and 28C for each color of black (K), yellow (Y), magenta (M), and cyan (C).

  The intermediate transfer belt 21 is stretched around the driving roller 29 and the driven rollers 30, 31, 32, and moves cyclically. The intermediate transfer belt 21 can be opposed to and contact the photosensitive drum 22K. A primary transfer voltage is applied to the position of the intermediate transfer belt 21 facing the photosensitive drum 22K by the transfer roller 25K, and the toner image on the photosensitive drum 22K is primarily transferred to the intermediate transfer belt 21.

  Further, a secondary transfer roller 33 is disposed opposite to the drive roller 29 that stretches the intermediate transfer belt 21. When the sheet S passes between the driving roller 29 and the secondary transfer roller 33, a secondary transfer voltage is applied by the secondary transfer roller 33, and the toner image on the intermediate transfer belt 21 is secondarily transferred to the sheet S. . A belt cleaner 34 is provided near the driven roller 32 of the intermediate transfer belt 21.

  The exposure position of the photosensitive drum 22K is irradiated with a black laser beam from the laser exposure device 19 to form a latent image on the photosensitive drum 22K. The charging charger 23K uniformly charges the entire surface of the photosensitive drum 22K. The developing device 24K supplies two-component toner composed of toner of each color and carrier to the photosensitive drum 22K by a developing roller. The cleaner 26K removes residual toner on the surface of the photosensitive drum 22K using a blade.

  The laser exposure device 19 scans the laser beam emitted from the semiconductor laser element in the axial direction of the photosensitive drum 22K, and includes a polygon mirror 19A, an imaging lens system 19B, a mirror 19C, and the like.

  Further, a separation roller 35, a transport roller 36, and a registration roller 37 for taking out the paper S in the paper feed cassette 18 are provided between the paper feed cassette 18 and the secondary transfer roller 33. A fixing device 38 is provided downstream. A paper discharge roller 39 is provided downstream of the fixing device 38 to discharge the paper S to the paper discharge unit 40.

  The operation of the image forming unit 10 will be briefly described. When image information is input from a scanner, a personal computer terminal, or the like, black (K), yellow (Y), magenta (M), and cyan (C) toner images are formed by the image forming units 20K to 20C. Black (K), yellow (Y), magenta (M), and cyan (C) toner images are multiplex-transferred at the same position on the transfer belt 21 where the toner image is formed, and a full-color toner image is obtained.

  The full color toner image on the intermediate transfer belt 21 is secondarily transferred onto the sheet S by the secondary transfer roller 31 at once. The sheet S is fed from the sheet feeding unit 18 to the position of the secondary transfer roller 33. The sheet S on which the toner image is secondarily transferred is sent to the fixing device 38 and the toner image is fixed on the sheet S. On the other hand, the intermediate transfer belt 21 is cleaned of residual toner by the belt cleaner 32 after the completion of the secondary transfer. The photosensitive drum 22 primarily transfers the toner image to the intermediate transfer belt 21, and then the residual toner is removed by the cleaner 26, so that the next image can be formed.

  Further, memory chips 41K, 41Y, 41M, and 41C are attached to the toner cartridges 28K, 28Y, 28M, and 28C, respectively. Each of the memory chips 41K, 41Y, 41M, and 41C is a memory configured in the IC, and information such as the remaining amount of toner is stored in the memory. For example, the amount of toner used is counted, and the remaining amount of toner stored in the memory decreases as the count value increases. In the following description, the memory chips are referred to as IC chips 41K, 41Y, 41M, and 41C.

  FIG. 2 is an external view of the MFP 10. There is a document table on the upper part of the main body 11 of the MFP 10, and an automatic document feeder (ADF) 12 is provided on the document table so as to be opened and closed. An operation unit 13 is provided on the upper portion of the main body 11. The operation unit 13 includes various operation keys 14 and a touch panel type display unit 15.

  A scanner unit 16 is provided below the ADF 12 in the main body 11, a printer unit 17 is provided at the center of the main body 11, and a plurality of cassettes 18 for storing various sizes of paper are further provided below the main body 11. It has.

  Further, a front cover 42 (hereinafter simply referred to as a cover 42) is provided on the front surface of the main body 11, and the cover 42 is opened when the toner cartridge 28 (28K to 28C) is replaced. Further, a sensor 43 for detecting opening / closing of the cover 42 is provided in the main body 11. The opening / closing of the cover 42 is not limited to the example detected by the sensor 43, but can be detected by a switch that is turned on / off according to the opening / closing of the cover 42. The sensor 43 and the switch constitute a detection element that detects opening and closing of the cover 42.

  When replacing the toner cartridge 28 (28K to 28C), the cover 42 is opened, the toner cartridge 28 is removed from the main body 11, the new toner cartridge 28 is mounted on the main body 11, and the cover 42 is closed. Accordingly, it is possible to determine whether the toner cartridge 28 is inserted or removed by detecting whether the cover 42 is opened or closed by a detection element such as the sensor 43.

  FIG. 3 is a block diagram showing a control system of the image forming apparatus (MFP) 10 according to the embodiment. In FIG. 3, the MFP 10 includes a main control unit 101, an operation panel 13, a scanner unit 16, and a printer unit 17.

  The main control unit 101 includes a main CPU, a ROM, a RAM, an image processing unit, and the like, and controls the overall operation of the MFP 10. Image data read by the scanner unit 16 and image data from the PC are input to the image processing unit of the main control unit 101 and subjected to various image processing, and are printed on paper by the printer unit 17.

  The operation panel 13 includes various operation keys 14 and a display unit 15 including liquid crystal. The operation keys 14 include a numeric keypad for instructing the number of copies to be printed. The display unit 15 has a touch panel function, and inputs various instructions such as paper size and printing magnification, and displays a remaining amount of toner, a message prompting replacement of the toner cartridge, and the like on the display unit 15.

  The scanner unit 16 includes a CCD driver or the like that drives an image sensor. The CCD driver drives the image sensor to read an image of a document and converts it into image data. The printer unit 17 includes a printer CPU 171, a control unit 172 that controls a charger, a developing unit, a transfer unit, and the like, a laser driver 173 that drives a laser of the laser exposure device 19, and a conveyance control that controls conveyance of the paper S. Part 173 and the like. The printer CPU 17 is connected to the main control unit 101.

  The printer unit 17 includes a CPU 50 that controls the IC chips 41K, 41Y, 41M, and 41C attached to the toner cartridges 28K, 28Y, 28M, and 28C. The CPU 50 is connected to the printer CPU 171. The memory chip group 41 in FIG. 3 is a general term for the IC chips 41K, 41Y, 41M, and 41C, and supplies information such as the remaining amount of toner stored in the memories of the IC chips 41K, 41Y, 41M, and 41C to the CPU 50. To do.

  The CPU 50 is supplied with the output of the sensor 43 that detects the opening and closing of the cover 42. In response to the output of the sensor 43, the CPU 50 replaces the toner cartridges 28K, 28Y, 28M, and 28C with the IC chips 41K, 41Y, 41M, and 41C. Control power on / off. Further, the CPU 50 is connected to a toner remaining amount calculation unit 44, and calculates the remaining amount of toner based on information from the IC chips 41K, 41Y, 41M, and 41C. When the toner remaining amount becomes equal to or less than a preset amount, the toner remaining amount calculating unit 44 displays the toner remaining amount on the display unit 15 or displays a message for prompting replacement of the toner cartridges 28K, 28Y, 28M, and 28C.

FIG. 4 is a connection diagram between the CPU 50 and the memory chip group 41, and an I2C bus is used for communication between the CPU 50 and the IC chips 41K, 41Y, 41M, and 41C. I2C is an abbreviation for Inter-Integrated Circuit and is formally called I ² C (I-squared-C). The I2C bus serially transmits data between a master and a slave using two signal lines of data (SDA) and clock (SCL).

  In FIG. 4, a CPU 50 and IC chips 41K, 41Y, 41M, and 41C include serial data (SDA) and serial clock (SCL) signal lines 51 and 52, and a signal line 53 (PWR) that controls power on / off. The signal lines 51 and 52 are connected to a power supply line 54 (for example, 3.3 V) via pull-up resistors R1 and R2. In FIG. 4, the CPU 50 is a master, and the IC chips 41K, 41Y, 41M, 41 are slaves.

  In I2C, a start condition, a stop condition, and a data exchange state can be set.

  FIG. 5 is an explanatory diagram showing the basic operation of I2C. In the I2C bus, there are a start condition, a stop condition, and a data exchange state. In I2C, two signals of serial data (SDA) and serial clock (SCL) are used, and at the time of data exchange, there is an agreement that SDA must be constant while SCL is “H”. When SCL is high “H” and SDA is changed from “H” to low “L”, a start condition S is established and communication is started. Furthermore, when SCL is “H”, changing SDA from “L” to “H” results in a stop condition E, and there is an agreement to end communication. Data exchange D0, D1,... Is divided into a write process and a read process.

  By the way, when one of the toner cartridges 28K to 28C is replaced (when the toner cartridge is inserted or removed), the power of the IC chips 41K to 41C is turned off. In this case, the I2C serial data (SDA) and the serial clock are turned off. (SCL) is forcibly operated in turn on the master side.

  That is, when the remaining amount of toner in any of the toner cartridges 28K to 28C becomes equal to or less than a preset amount, the corresponding toner cartridge is replaced. When any of the toner cartridges 28K to 28C is replaced, the MFP 10 is replaced with the power on. Therefore, the power of all the IC chips 41K to 41C is turned off so that the IC chips do not break down. However, there is a problem that the I2C bus hangs up when I2C is used for the interface with the IC chip and the power of the IC chips 41K to 41C is turned off.

  For example, when one of the toner cartridges 28K to 28C is inserted and removed, and the PWR is turned off (“L”), the state of the SCL and SDA signals may be the state shown in FIG. In the state S1 of FIG. 6, although it tried to turn off the PWR, it becomes the same state as the start condition S, and the CPU 50 misrecognizes that the bus right has been taken away by another master and cannot communicate thereafter. And sometimes the bus hangs up. That is, any of the IC chips 41K to 41C as slaves is erroneously recognized as the master, and the CPU 50 does not respond.

  Therefore, in the embodiment, when the power of the IC chips 41K to 41C is turned off when the toner cartridges 28K to 28C are inserted and removed, the I2C serial data (SDA) and the serial clock (SCL) are forcibly operated in order on the master side (CPU 50). The I2C bus is prevented from hanging up.

  Hereinafter, an operation for preventing hang-up will be described with reference to FIG. S2 in FIG. 7 indicates a state when the power of the IC chips 41K to 41C is turned off, and E2 indicates a state when the power is turned on. As shown in FIG. 4, the CPU 50 serving as a master and the IC chips 41K to 41C serving as slaves are connected by an I2C bus, and the power (PWR) of the IC chips 41K to 41C can be turned on / off from the CPU 50. ing.

  As shown in FIG. 7, when one of the toner cartridges 28K to 28C is inserted or removed, the PWR is turned off ("L") to prevent the IC chips 41K to 41C from being damaged by hot plugging. First, the SCL is first forced from “H” to “L”, then the SDA is forcibly driven sequentially from “H” to “L”, and then the PWR is changed from “H” to “L”. Similarly, when PWR is turned on (“H”), the bus is forcibly driven sequentially so that PWR is first set to “H”, then SDA is set to “H”, and SCL is set to “H”.

  By performing such an operation, when the power of the IC chips 41K to 41C is turned off or on, the start condition S or the stop condition E is controlled so that the I2C bus hang-up can be prevented.

  FIG. 8 is a flowchart showing the above-described hang-up prevention operation. In FIG. 8, when the operation starts, in operation (Act) A1, it is determined whether or not the cover 42 is opened in order to replace any of the toner cartridges 28K to 28C. Whether the cover 42 is opened can be detected by the sensor 43. If it is determined that the cover 42 is opened, the SCL of the I2C bus is changed from “H” to “L” in operation A2. Next, in operation A3, SDA is changed from "H" to "L". In operation A4, PWR is set to “L” and POWER OFF is set. Thereafter, the toner cartridges 28K to 28C are removed.

  After the toner cartridges 28K to 28C are removed and new toner cartridges 28K to 28C are mounted, in operation A5, it is determined whether or not the cover 42 is closed. Whether or not the cover 42 is closed can be detected by the sensor 43. If it is determined that the cover 42 is closed, in operation A6, the PWR of the I2C bus is turned on ("H") and turned on. In operation A7, SDA is changed from "L" to "H". Next, in operation A8, SCL is changed from "L" to "H", and the operation is ended (END).

  According to the embodiment described above, when the power supply of the IC chips 41K to 41C is turned off when the toner cartridges 28K to 28C are replaced, it is possible to reliably prevent the I2C bus from hanging up.

  In the above embodiment, the example in which the opening / closing of the cover 42 is detected by the sensor 43 has been described. However, the opening / closing of the cover 42 can also be detected by a switch. Further, the example in which the toner cartridges 28K to 28C are replaced by opening and closing the front cover 42 has been described. However, the present invention can also be applied to a type in which the cover 42 is provided on the side surface of the main body 11 and the toner cartridges 28K to 28C are replaced from the side surface. .

  Further, although an example in which four toner cartridges 28K to 28C are provided has been described, the number of toner cartridges is not limited to four. It may also have one (black) toner cartridge. As a matter of course, the number of IC chips varies depending on the number of toner cartridges.

  In addition, although several embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof as well as included in the scope and gist of the invention.

10. MFP (image forming apparatus)
DESCRIPTION OF SYMBOLS 11 ... Main body 13 ... Operation panel 15 ... Display part 16 ... Scanner part 17 ... Printer part 20 ... Image forming part 28K, 28Y, 28M, 28C ... Toner cartridge 41K, 41Y, 41M, 41C ... Memory chip (IC chip)
42 ... Cover 43 ... Sensor (detection element)
44 ... Toner remaining amount calculating unit 50 ... CPU
51 ... SDA signal line 52 ... SCL signal line 53 ... PWR (power supply) control line 54 ... power supply line

Claims (3)

A detection element for detecting opening and closing of a cover provided on the main body;
A memory chip attached to a toner cartridge in the main body ;
Communicates via the memory chip and I2C bus, to acquire the information recorded in the memory chip, in the case of off or on controlling the power of said memory chips during insertion and removal of the toner cartridge, before Symbol I2C bus And a CPU that controls so as not to enter a start condition and a stop condition state,
When the CPU detects that the cover is opened by the detection element, the CPU determines that the toner cartridge is removed, and sequentially turns off the serial clock (SCL) and serial data (SDA) of the I2C bus. When the power supply of the memory chip is controlled to be off and the detection element detects that the cover is closed, it is determined that the toner cartridge is mounted, the power supply of the memory chip is turned on, and then the I2C bus An image forming apparatus which sequentially turns on serial data (SDA) and serial clock (SCL) .   The image forming apparatus according to claim 1, wherein the toner cartridge includes a plurality of toner cartridges, the memory chip is attached to each of the toner cartridges, and power on / off of the memory chips is controlled by the CPU. The detection element detects the opening and closing of the cover provided on the main body,
Thus the CP U to communicate via the memory chip and the I2C bus which is attached to the toner cartridge in the main body, and acquires information recorded in the memory chip,
When off or on controlling the power of said memory chips during insertion and removal of the toner cartridge, before SL as I2C bus is not a start condition and a stop condition state, detects that the cover is opened by said detecting device When the CPU determines that the toner cartridge is removed, the serial clock (SCL) and serial data (SDA) of the I2C bus are sequentially turned off, and then the power supply of the memory chip is turned off.
When it is detected by the detection element that the cover is closed, the CPU determines that the toner cartridge is mounted, and after turning on the power of the memory chip, the I2C bus serial data (SDA) and serial clock A method of controlling an image forming apparatus in which (SCL) is sequentially turned on .

Images