JP4169308B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a mechanism for forming an image represented by image data on a sheet or paper, that is, an image forming engine, an engine board equipped with an electric circuit for controlling the operation of each image forming process element, and image data and The present invention relates to an image forming apparatus including an application board equipped with an electric circuit for giving an image forming instruction. A typical example of this image forming apparatus is a printer, a copier, a facsimile, or a network communication function, an original scanner function, or an image storage function in addition to these functions, and an image is sent to a personal computer connected to a network. This is a multi-function copier that can input and output.
[0002]
[Prior art]
For example, an electrophotographic image is formed by charging a photosensitive drum, projecting light onto a charged surface, exposing, developing an electrostatic latent image formed by exposure to a toner image, and transferring the toner image onto a recording sheet. In the case of an image forming apparatus using an engine, an engine board that controls the image forming engine includes an electric circuit (driver) that drives an image forming function element, a detection circuit that processes a detection signal of a sensor in the image forming engine, and There is a microcomputer system including a CPU, a RAM, and a ROM. Since the recording density is likely to change, the CPU adjusts the image forming process conditions such as the high voltage of the charging charger, the developing bias, and the discharge lamp voltage so that the developing density is detected and maintained at an appropriate value. (Adjustment value) is stored in the memory.
[0003]
Even during standby when the main power switch of the image forming apparatus is turned off, or even when the main power switch is turned on, the power supply to the image forming engine and engine board is shut off by turning off the sub power switch for power saving. In order to hold the aforementioned adjustment value in the memory, the engine board is provided with a nonvolatile memory (NVRAM), which holds the adjustment value of the image forming process condition.
[0004]
Further, for example, in the case of the above-mentioned multi-function copying machine, a copying application that performs copying by giving commands to the document scanner and the engine board in accordance with a user instruction via an operation / display board that is an interface with the user. Board (hereinafter referred to as a copy board), a printer application board (hereinafter referred to as a printer board) that gives commands to the engine board in response to a printout instruction from a personal computer, and prints out the data provided by the personal computer with the imaging engine / In response to a user instruction via the display board or personal computer, an instruction is given to the document scanner, an image of the document is read and sent to the facsimile communication line, or an image data sent to the engine board is given to the engine board. Facsimile application board that prints out with image forming engine (Hereinafter, FAX board) there is.
[0005]
For example, the above-mentioned copying board includes an electric circuit for energizing the operation / display board to generate an input signal and driving the display, and a microcomputer system including a CPU, RAM and ROM. There are many copy conditions such as paper feed size, copy magnification, copy density, number of copy sets, single-sided / double-sided mode, editing, etc., and the contents of standard conditions (standard mode) can be set as initial values. The copy board also has a non-volatile memory (NVRAM) in order to retain usage management information such as this standard mode (initial value), occasional user set values, usage history, and abnormality history in the memory. In the image forming apparatus disclosed in Japanese Patent Laid-Open No. 09-200403, a program storage area of a function expansion portion is provided in the NVRAM area in order to facilitate function expansion.
[0006]
[Problems to be solved by the invention]
Since the types of adjustment values of the above-described image forming process conditions that should be held in the nonvolatile memory of the engine board are relatively limited, the nonvolatile memory includes various application boards (for example, the above-described copying board, printer board, and It is considered desirable to put them on one of the (FAX boards) in consideration of the cost of the engine board alone.
[0007]
The first object of the present invention is to simplify the memory of the engine board. The nonvolatile memory for storing the adjustment values of the image forming process conditions of the image forming engine is omitted from the engine board, and The second purpose is to realize nonvolatile storage.
[0008]
[Means for Solving the Problems]
(1) an engine board (1) including first control means (CPU 19) for controlling the image forming engine (5) ;
Second control means (CPU 20) for controlling the engine board, first information for operation setting referred to by the first control means ( adjustment value of image forming process condition), and control of the engine board An application board (2) including a non-volatile memory (27) for holding second information (operation management information) for operation setting referred to by the second control means ;
A main power switch (12) that is turned on and off to supply power to the application board ;
A power supply circuit (11) for applying an operating voltage to the application board by turning on the main power switch ;
A sub power switch (13) that is turned on and off to supply power to the engine board by the second control means ;
For holding the first information, a volatile memory on the engine board, wherein the main power switch is powered continuously between on (15),
It is connected to the output power supply line of the power supply circuit to the volatile memory and the output line of the sub power switch, and is obtained by turning off or on the main power switch and turning off or on the sub power switch by the second control means. Main power-on detection means (28) for detecting the output level (Ps) generated ,
An image forming apparatus comprising,
It said first control means (CPU 19) is
The main power switch is on according to the output level (Ps) detected by the main power on detection means , or during the continuous on of the main power switch and from the off of the sub power switch to on determining whether the re-feeding by Setsu換Ri (S4),
If it is determined that the main power switch is on, after the initialization of the volatile memory, a download request for writing the first information held in the nonvolatile memory to the volatile memory is issued. In addition to giving to the application board (S5, S6) , waiting for the completion of downloading of the first information to the volatile memory, starting a task for the imaging engine (S9, S10) ,
If it is determined that the power is being repowered while the main power switch is continuously turned on and the sub power switch is switched from off to on, the first information held in the non-volatile memory is stored in the first information. After initialization of the area other than the area stored in the volatile memory, the download request is suspended and the task is activated (S14, S15) ,
An image forming apparatus.
[0009]
In addition, in order to make an understanding easy, the symbol or corresponding matter of the corresponding element of the Example which is shown in drawing and mentioned later in parentheses is added for reference. The same applies to the following.
[0010]
According to this, since the 1st control means (19) expand | deploys the 1st information (adjustment value) of a non-volatile memory (27) to the volatile memory (15) , the 1st control means (19) expand | deployed to the volatile memory (15). The operation of the image forming engine (5) can be set and controlled with reference to one information (adjustment value). When deploying to the volatile memory (15), the volatile memory (15) is initialized, that is, it is initialized before data download, so the data on the volatile memory (15) due to noise at power-on etc. Even if data corruption occurs, the risk of adversely affecting the load data can be reliably prevented.
[0011]
Since after the main power switch (12) is a volatile memory (15) is always energized in the engine board (1), after off / on of the auxiliary power switch (13) is also a volatile memory (15) there remains the proper first information (adjustment values), since the hold-down load of the first information to the volatile memory (15) from the non-volatile memory (27), time duration, following tasks necessary for it (30 to 33) is earlier time to start the, not only shorten the rise time, the risk of writing incorrect data to data corruption occurs volatile memory (15) can be reliably prevented.
[0012]
Since the download request is not issued when the sub power switch (13) is turned off / on, the time for starting the next task (30 to 33) is accelerated by the time required for the download, and the rise time can be shortened.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
(2) The output level (Ps) is determined by the voltage of the capacitor that is charged and discharged with a delay as the voltage of the output power supply line of the power circuit (11) rises and the voltage when the sub power switch is turned off or on. The image forming apparatus according to (1) above , which is an output of a logic circuit (31) using a circuit .
[0014]
(3) The engine board determines whether the first information held in the non-volatile memory is appropriate. If the engine board determines that the first information is appropriate, the engine board writes the first information to the volatile memory, The image forming apparatus according to (1) , wherein when it is determined that there is a default value, a default value is written in the volatile memory .
[0015]
According to this, the validity of the download data (adjustment value) is judged and written to the volatile memory (15) on the engine board (1), so incorrect data is written to the volatile memory (15). It is possible to reliably suppress malfunction caused by. When the data is inappropriate, the default value is written, so that it is possible to prevent a fatal error such as runaway caused by processing based on wrong data when the image forming engine starts operation.
[0016]
(4) When the first control unit rewrites the value of the first information in the volatile memory, the engine board notifies the application board and rewrites the data in the nonvolatile memory on the application board. The image forming apparatus according to (1) above.
[0017]
According to this, since the change information on the engine board (1) is surely in the nonvolatile memory (27) of the application board (2), the image can be created even if the main power switch (12) is turned on / off. The engine (5) can be reliably operated in the state before being re-input.
[0018]
Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.
[0019]
【Example】
FIG. 1A shows an embodiment of the present invention. 1A shows an image forming apparatus CPR including a printer board 3, a FAX board 4, and a communication board 9 in addition to the copy function devices (1, 2, 5 to 8). This is a multi-function copier. The copying function device includes an operation / display board 6 for a user to input a command 6, a document scanner 7 for reading an image of a document and converting it into image data, and an ADF (automatic document feeder) for feeding and discharging the document. 8. Electrophotographic imaging in which the photosensitive drum is charged and exposed by projecting light onto the charged surface, and the electrostatic latent image formed by the exposure is developed into a toner image and transferred to a recording paper. Commands are given to the scanner 5 and the engine board 1 in response to a copy instruction from the engine 5 equipped with an electric circuit for controlling the operation of the engine 5 and each image forming process element in the engine 5 A copy board 2 for copying, and these constitute a so-called digital copying machine.
[0020]
The printer board 3 gives a command to the engine board 1 in response to a printout instruction given from a personal computer (not shown) via the communication line 10 and the communication board 9, and prints out data given by the personal computer with the image forming engine 5. The FAX board 4 gives an instruction to the document scanner 7 in accordance with a user instruction via the operation / display board 6 or a personal computer, reads an image of the document, and sends it to or from the facsimile communication line. The coming image data is printed out by the image forming engine 5 by giving an instruction to the engine board 1.
[0021]
As shown in FIG. 1B, each of the boards 1 to 4 includes a central processing unit CPUs 19 to 22, read-only memory ROMs 23 to 26 for storing programs, and volatile memory RAMs 15 to 18 for holding temporary data. In addition to these, there are an input / output electric circuit (input / output interface), an inter-board communication circuit (communication interface), a bus and a connector (not shown). The computer system is connected by a bus and a connector (not shown). Each microcomputer (CPU 19 to 22) controls an electric circuit on the board on which it is mounted, a load or peripheral device connected to the board, and inter-board communication and data transfer.
[0022]
In this embodiment, the copy board 2 is further equipped with a unique nonvolatile memory (NVRAM) 27. When the main power switch 12 is turned on, the power circuit 11 generates a voltage required for the operation of the image forming apparatus CPR, and an operating voltage is applied to the copy board 2, the printer board 3 and the FAX board 4 through the standby power supply line.
[0023]
Since the RAM 15 on the engine board 1 is supplied with power through the standby power supply line, the stored data in the RAM 15 is stored (held) while the main power switch 12 is on, and disappears when the main power switch 12 is turned off. .
[0024]
However, the other elements on the engine board 1 and the image forming engine 5 are not supplied with power unless the sub power switches 13 and 14 are turned on by the CPU 20 of the copy board 2.
[0025]
In this embodiment, the main power-on detection circuit 28 is connected to the standby power supply line to the RAM 15 and the output line of the sub power switch 13. When the main power switch 12 is switched from OFF to ON and a predetermined voltage is applied to the standby power supply line, the capacitor 30 is charged through the resistor 29, and after the delay time of Tu, the voltage of the capacitor 30 changes to the standby power supply line. Stand up near voltage. When the sub power switch 13 is turned on within a time shorter than this Tu, the output Ps of the AND gate 31 stays at the low level L, and the CPU 19 activated by the output of the sub power switch 13 performs the AND gate operation when the sub power switch 13 is activated. If the output Ps of 31 is L, it is recognized that the current activation is immediately after the main power switch 12 is turned on.
[0026]
When more than Tu has passed since the main power switch 12 was turned on and the sub power switch 13 is also turned on, the output Ps of the AND gate 31 is at the high level H. If the main power switch 12 remains on and a standby state waiting for an instruction such as reading, printing or copying of a document image continues for a set time or longer, the CPU 20 of the copy board 2 turns off the sub power switches 13 and 14. That is, the power saving standby mode is entered. Then, when the above instruction is entered, the CPU 20 turns on the sub power switches 13 and 14, whereby an operating voltage is applied to the CPU 19 and the CPU 19 is activated. At this time, since the voltage of the capacitor 30 is high, the output Ps of the AND gate 31 is at the high level H when the CPU 19 is started, and the CPU 19 returns from the power saving standby mode, that is, the main power switch 12 is continuously turned on. It is recognized that the secondary power supply switch 13 is activated by re-feeding by switching from off to on. When the main power switch 12 is turned off, the capacitor 30 is discharged through the resistors 29 and 32 and becomes the equipment ground potential.
[0027]
Reference is made to FIG. In order to download and store the adjustment value of the image forming process condition of the image forming engine 5 in the volatile memory RAM 15 on the engine board 1 from the nonvolatile memory NVRAM 27 on the copy board 2, it is stored in the RAM 15 on the engine board 1. Defines an area 15a for storing data to be downloaded (adjustment values for image forming process conditions), and the area 23a of the ROM 23 on the engine board 1 contains data to be downloaded (adjustment values for image forming process conditions). ) Individual types and ranges, as well as default values (initial values) are written.
[0028]
2B shows an outline of the functions of the engine board 1, and FIG. 3 shows an outline of the download process of the CPU 20 immediately after the main power switch 12 is turned on and the sub power switch 13 is turned on. An overview of the download process of the CPU 19 immediately after the change is shown. When the main power switch 12 is turned on and an operating voltage is applied, the CPU 20 of the copy board 2 is activated to turn on the sub power switches 13 and 14 (steps S1 and S2). When the sub power switch 13 is turned on, the CPU 19 of the engine board 1 is activated, and the output of the AND gate 31 of the main power on detection circuit 28 indicates whether this activation is immediately after the main power switch 12 is turned on. Determination is made with reference to Ps (steps S3 and S4). As described above, when the output Ps is at the low level L, the current activation is immediately after the main power switch 12 is turned on, and when the output Ps is the high level H, the current activation is performed during the continuous on of the main power switch 12. This is due to re-feeding by switching the sub power switch 13 from OFF to ON.
[0029]
If the current activation is immediately after the main power switch 12 is turned on (Ps: L), the CPU 19 of the engine board 1 stores a RAM area 15a for storing downloaded data (adjusted values of image forming process conditions). Initialization is performed via the copier interface 33 as shown by a route (2) shown in FIG. 2B (step S5). In the following, the word “step” is omitted in parentheses and only the step symbol is shown, and the route number shown in FIG. Is added.
[0030]
When various initial operations are completed, the CPU 19 of the engine board 1 sends a download request for the NVRAM 27 to the copy board 2 (S6, (5)). In response to this request, the CPU 20 of the copying board 2 throws the adjustment values of the image forming process conditions of the NVRAM 27 sequentially into the area 15a of the RAM 15 (S17, S6, (6), (2)). The copier interface 33 on the side determines whether or not the transfer data is correct based on information (reference information having a type, a specifiable range, etc.) written in the area 23a of the ROM 23 (S9). Otherwise, the default value written in the area 23a of the ROM 23 is written in the area 15a of the RAM 15 (S12, (2), (3)), and at the same time, it is determined that the communication is abnormal, and the subsequent processing is canceled (S13). .
[0031]
When normal download continues and the data to be sent out by the copy board 2 is completed, the copy board 2 notifies the engine board 1 to that effect (S18). In response to this, the CPU 19 of the engine board 1 issues an activation notification to each of the tasks 35 to 38 that have been waiting for the engine board 1 (S10, (1)). Thereafter, each task performs an initial operation, and finally the image forming apparatus CPR enters the READY state (S11). The above is the operation of the image forming apparatus CPR immediately after the main power switch 12 is switched from OFF to ON.
[0032]
Next, after the actual operation of the image forming apparatus CPR, for example, the start cycle for preparing the print of the image forming engine 5 and the image formation for printing or copying, any task of the engine board 1 is performed. On the engine board 1 when the adjustment value of the image forming process condition is changed, the corresponding adjustment value in the area 15a of the RAM 15 is rewritten accordingly, and the corresponding data in the NVRAM 27 is rewritten accordingly. This process will be described with reference to FIG. When each of the tasks 35 to 38 changes the adjustment value of the image forming process condition (S21, S22), it notifies the copier interface 33 (S23, (4)), and the copier interface 33 adjusts the corresponding adjustment of the storage area 15a. The value data is rewritten (S25, S26, (2)), and a request to write the corresponding data in the NVRAM 27 is notified to the copy board 1 (S27, (5)).
[0033]
By the way, in the present image forming apparatus CPR, in order to reduce power consumption during night mode and long standby time and to shorten the operable time when returning to the image forming enabled state, the copying board 2 is provided with the engine board 1 and Sub power switches 13 and 14 for determining whether the image forming engine 5 is turned on / off are provided. When the power supply circuit 11 starts voltage output by switching the main power switch 12 from off to on, the RAM 15 on the engine board 1 is indefinite because the power has just been supplied, but as described above, After that, after the sub power switch 13 is turned on and the CPU 19 is activated, the adjustment value of the image forming process condition in the NVRAM 27 is downloaded to the RAM 15, so that a data error occurs in the adjustment value of the image forming process condition of the RAM 15. Absent. Thereafter, as long as the main power switch 12 is on and power is supplied, the data on the RAM 15 is retained.
[0034]
On the other hand, the CPU 19 on the engine board 1 stops its operation because the power is not supplied when the sub power switches 13 and 14 are turned off in accordance with an instruction from the CPU 20 of the copy board 2 due to the hardware configuration.
[0035]
Refer to FIG. 3 again. When the sub power switches 13 and 14 are turned on again (in response to an instruction from the CPU 20 of the copy board 2), the CPU 19 starts to operate, referring to the output Ps of the AND gate 31 of the main power on detection circuit 28. Since it means H, which means that the sub power switches 13 and 14 are turned on again (on again) while the power switch 12 is kept on, the CPU 19 initializes the area excluding the nonvolatile data storage area of the RAM 15 (S14), Then, the tasks 35 to 38 are requested to start the operation all at once (S15, S16).
[0036]
As described above, when the CPU 19 is activated (S3), the start of power supply to the CPU 19 is linked to the turning on of the main power switch 12 (Ps = L), or the main power switch 12 remains on. In step S4, the main power switch 12 is turned on (Ps = L). The RAM 15 is initialized and nonvolatile data (the adjustment value of the image forming process condition in the NVRAM 27) is downloaded to the RAM 15. When the sub power switch is turned on again with the main power switch 12 kept on, the area of the RAM 15 excluding the nonvolatile data storage area 15a is initialized (S14), and each task (30 to 33) is immediately activated. Since (S15), compared with the processing (S5 to S11) when the main power switch 12 is turned on, the processing time from when the power is turned on until the task is started is shorter.
[Brief description of the drawings]
FIG. 1A is a block diagram showing an outline of a configuration of an embodiment of the present invention, and FIG. 1B is a main element of a microcomputer system on boards 1 to 4 shown in FIG. FIG.
2A is a plan view schematically showing a data writing area allocated on the ROM 23 and RAM 15 shown in FIG. 1B; FIG. 2B is a diagram showing several main processing functions of the engine board 1; FIG.
FIG. 3 is a flowchart showing the contents of data transfer immediately after the engine board 1 and the copy board 2 are powered on.
FIG. 4 is a flowchart showing data processing on the engine board 1 when the engine board 1 changes an adjustment value of an image forming process condition.
[Explanation of symbols]
28: main power-on detection circuit 29, 32: resistor 30: capacitor 31: AND gate

Claims (4)

An engine board including first control means for controlling the image forming engine;
Second control means for controlling the engine board; first information for operation setting referred to by the first control means; and second information for operation setting referred to by the second control means for controlling the engine board. 2 an application board including a non-volatile memory for holding information;
A main power switch that is turned on and off to supply power to the application board;
A power supply circuit for applying an operating voltage to the application board by turning on the main power switch;
A sub power switch for performing on / off control for supplying power to the engine board by the second control means;
A volatile memory on the for holding the first information, the engine board, wherein the main power switch is powered continuously during the on,
It is connected to the output power supply line of the power supply circuit to the volatile memory and the output line of the sub power switch, and is obtained by turning off or on the main power switch and turning off or on the sub power switch by the second control means. Main power-on detection means for detecting the output level to be output;
An image forming apparatus comprising,
The first control means includes
The main power switch is on according to the output level detected by the main power on detection means, or the sub power switch is switched from off to on while the main power switch is continuously on. To determine if it is repowered by
If it is determined that the main power switch is on, after the initialization of the volatile memory, a download request for writing the first information held in the nonvolatile memory to the volatile memory is issued. Give to the application board, wait for the completion of the download of the first information to the volatile memory, start a task for the imaging engine,
If it is determined that the power is being repowered while the main power switch is continuously turned on and the sub power switch is switched from off to on, the first information held in the non-volatile memory is stored in the first information. After initializing an area other than the area stored in the volatile memory, the download request is suspended and the task is activated .
An image forming apparatus. The output level is an output of a logic circuit using a voltage of a capacitor that is delayed and charged according to a rise and fall of the voltage of the output power supply line of the power supply circuit and a voltage when the sub power switch is turned off or on. the image forming apparatus according to claim 1. The engine board determines whether the first information stored in the non-volatile memory is appropriate. If the engine board determines that the first information is appropriate, the engine board writes the first information in the volatile memory and determines that the first information is inappropriate. when writes the default values in the volatile memory, the image forming apparatus according to claim 1. The engine board notifies the application board when the first control means rewrites the value of the first information in the volatile memory, and rewrites data in the nonvolatile memory on the application board. 2. The image forming apparatus according to 1.

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