JP4499491B2 - Image forming apparatus and printed sheet counting method - Google Patents

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus provided with a counter for the number of printed sheets.

A printed sheet counter of a printer, a copier, a multifunction machine, or the like is important information used for calculating the maintenance cost and usage fee of the device. Recently, image forming apparatuses have also become multifunctional, and are counted in detail for each type of color / monochrome, print / copy / fax, paper size, and the like. Generally, this counter information is stored in a non-volatile memory (NVRAM, EEPROM, FRAM, battery-backed SDRAM, etc.) so that data retained due to a device failure or the like is not lost. Further, a counting method has been devised so that the number of sheets is correctly counted even when an accident such as misfeed or jam (paper jam) occurs (see, for example, Patent Document 1 and Patent Document 2).
JP 2000-20277 A JP 2000-194239 A

However, since the above-mentioned nonvolatile memory is expensive, the cost of the image forming apparatus can be reduced if the counter information can be stored in a large-capacity memory (for example, an IC card, an SD card, a hard disk, etc.) even at a low speed. However, as a method for storing the counter information in the low-speed memory, the system that counts up each time one sheet is printed has a problem that the system performance decreases. In particular, when a data write error occurs when writing data to a low-speed device, a write retry occurs and the system performance may be significantly reduced, which is a problem in mounting on a product. As a countermeasure, a method of temporarily storing a plurality of print results in the RAM and collectively reflecting them in the counter later is considered. However, the counter value is not accurately counted when the power is turned off during printing. There's a problem.
The present invention has been made in consideration of the above-described circumstances, and provides an image forming apparatus that eliminates the speed limitation of an inexpensive, low-speed, large-capacity nonvolatile memory and maintains the reliability of the counter. Objective.
In this specification, “IC card” refers to all cards such as PC cards, SD cards, multimedia cards, Memory Stick (registered trademark), and CompactFlash (registered trademark) that comply with the PCMCIA standard. It is not a general plastic card with a built-in IC chip.

In order to solve the above-described problems, according to the first aspect of the present invention, in the image forming apparatus having a counting unit for counting the number of printed sheets, the counting unit stores a numerical value for determining the end of the print job. a reference register, respectively provided in the nonvolatile memory, the sub-counter that is incremented each time the output one during a print job processing, the reference register and a reference to the end of the print job and a sub counter is judged printed printing completion display means for indicating the completion, and includes a main counter for holding the cumulative number of printed sheets in the image forming apparatus, and when a print job ends, when the printing completion display means does not indicate ends when the power is turned on, the The number of printed sheets is counted by adding the value of the sub-counter to the main counter.
By doing this, even if it is necessary to turn off the power during the print job, the print completion display means that the number of uncounted pages is found when the power is turned on again, and the uncounted number is stored in the sub-counter. ing.
According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the main counter and the print completion display unit are constituted by a non-volatile memory that is slower than the sub-counter.
By doing so, the main counter and the print completion display means with a small number of accesses can be configured with a low-speed nonvolatile memory, and the cost can be reduced.
According to a third aspect of the present invention, in the image forming apparatus according to the first aspect, the sub-counter and the reference register are configured in an ASIC.
By doing so, it is possible to reduce the size and cost of the apparatus.

Furthermore, claim 4 is the image forming apparatus according to any one of claims 1 to 3, wherein the main counter and the printing completion display means operation of the image forming apparatus, the type of separate or output paper color / monochrome It is characterized by counting in association with.
In this way, detailed counting can be performed.
Further, a fifth aspect is the image forming apparatus according to any one of claims 1 to 4, wherein the main counter and the printing completion display means is characterized by being configured in a removable non-volatile memory.
By doing so, the output amount in a desired group unit can be counted. Further, a commercially available IC card, flash memory, etc. can be used, and the cost can be reduced.
Further, according to claim 6, in the image forming apparatus according to any one of claims 1 to 5, provided the number of jobs simultaneously function of the image forming apparatus the sub-counter and the reference register, for each of the job It is characterized by adding and counting.
In this way, even when a plurality of jobs are processed simultaneously, it is not necessary to have the same number of sub-counters as the number of main counters, and the cost can be reduced.
According to a seventh aspect of the present invention, there is provided a method for counting the number of printed sheets in an image forming apparatus, wherein the number of printed sheets is set in a reference register at the start of a print job, a value indicating incomplete is set in a print completion flag provided in a nonvolatile memory, Each time one sheet is output, the sub-counter provided in the non-volatile memory is incremented, and when the value of the sub-counter becomes equal to the value of the reference register, the value of the sub-counter is held as the cumulative number of printed sheets of the image forming apparatus. In addition, the value is added to the main counter provided in the non-volatile memory, the value indicating completion is set in the print completion flag, and the sub-counter is set to zero, and the print completion flag is referred to when the image forming apparatus is turned on. If a value indicating incomplete is set, the value of the sub-counter is added to the main counter to add the uncounted number of sheets. The features.

  According to the present invention, the non-volatile memory of the counter can be divided into a memory with a large number of accesses and a memory with a small number of accesses.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram illustrating a system configuration example of an image forming apparatus according to the present invention. In this embodiment, each device is connected by the same bus, but there may be a device controlled by an ASIC (application specific IC) by an individual bus.
The printer controller 100 is a part that processes a print request from the host PC 112 and issues a print instruction to the engine 111, and is built in a printer, a multifunction peripheral, a copier, or the like. The CPU 101 executes a program recorded in the ASIC 102 or the ROM 104 to realize the function of the printer controller 100. The ASIC 102 is programmed to control various interfaces. The IC card I / F 103 is an interface provided with an external storage card connector of the IC card 110. Examples of the external storage card include a PC card, an SD card, and a compact flash (registered trademark). A RAM 105 is a memory that temporarily stores a processing result when the CPU 101 executes the program.
The engine I / F 108 is an interface for bus conversion with the image output engine 111 and plays a role of sending image data in synchronization with the operation of the engine 111 that actually outputs an image on paper. The network I / F 109 supplies an interface for performing communication with the host PC 112 that inputs a print job or the like, and is compatible with a wired LAN such as IEEE802.3 or a wireless LAN such as IEEE802.11. . An operation unit I / F 107 is an interface for exchanging information with an operation unit (operation panel). The expansion connector 106 is a DIMM (Dual Inline Memory Module) mounting connector.

FIG. 2 is a diagram for explaining the configuration of the counter of the present invention. In this embodiment, the high-speed and small-capacity memory is an ASIC built-in nonvolatile memory, and the low-speed and large-capacity memory is an external IC card. The ASIC 102 has a non-volatile memory area, and has a “sub-counter 201” and a “reference register 202” area. The IC card 110 includes areas of “main counters # 1 to #N” and “print completion flags # 1 to #N”. Each counter and reference register are controlled by software.
The main counter 203 is a counter that stores the total number of printed sheets of the apparatus, and adds the number of printed sheets for each print job. The data length is composed of several bytes (for example, 2 bytes if about 30,000 are used in one year), and can be counted more than 1 million times. When the countable number exceeds the device rewritable number, it is necessary to take a measure such as changing the write address according to the count value. However, since it is not the essence of the present invention, the detailed description is omitted. For example, when a 10-page file is printed out, it is incremented by 10 times when all printing is completed.
The sub-counter 201 is a counter that stores the number of printed sheets for each print job. When a print job is being executed, the sub-counter 201 counts up each time one sheet is output and is reset for each print job. The data length is composed of several bits. For example, when composed of 8 bits, it is possible to count up to 255 sheets in one print job. For example, when a 10-page file is printed out, it is incremented by 1, 2, 3, 4,.

The reference register 202 is a register that stores the scheduled number of prints for each print job. It is set before printing starts and is reset for each print job. The data length consists of several bits. The same number of bits as the sub-counter is required. Since the reference register may be cleared when the power is turned off during printing, it may be stored in the RAM. For example, when a 10-page file is printed out, 10d (0x0A) is set before printing is started. The planned print number can be obtained before printing by analyzing the PDL (Page Description Language) of the print job.
The print completion flag (print completion display means) 204 is set to 1 at the start of printing, with an initial value of 1, and is set to 1 after the end of printing. The data length is composed of 1 bit. By assigning the least significant bit or the most significant bit of the main counter 203 to this flag, the flag can be set simultaneously with the rewriting of the main counter 203. For example, when a 10-page file is printed out, it is cleared to 0 before starting printing and set to 1 after printing 10 pages.
A plurality (N) of print completion flags 204 corresponding to the main counter 203 are prepared because the number of printed sheets is determined by a printing method such as monochrome / color (color), printer / copy (function), A4 / A3 (paper), etc. This is because it is assumed that the data is stored in another counter. For example, the counter is assigned as follows.
(Example)
Main counter # 1, print completion flag # 1: Monochrome print output Main counter # 2, print completion flag # 2: Color print output Main counter # 3, print completion flag # 3: Monochrome copy output Main counter # 4 , Print completion flag # 4: Color copy output

Next, the operation of the counter configured as described above will be described. FIG. 3 is a flowchart showing the counter processing in the image forming apparatus of the present invention.
When the power is turned on, the print completion flag 204 is read (step 302). If there are a plurality of print completion flags 204, all are read. When the print completion flag 204 cleared to 0 is found (YES in step 302 (= 0)), the current value of the sub-counter 201 is added to the main counter 203 corresponding to the print completion flag 204 cleared to 0. . At the same time, the print completion flag 204 is set to 1 (step 303). If the device on which the main counter 203 is mounted is faulty, or if the device on which the main counter 203 is mounted is a detachable device and is not mounted, it stays at this step and stops with an error (Not shown). If all the print completion flags 204 are set to 1 (NO in step 302 (= 1)), the process of step 304 is performed. In step 304, the reference register 202 and the subcounter 201 are initialized to all 0 bits. When the reference register 202 is stored in the RAM, the reference register 202 is initialized when the power is turned off, so that initialization in this step is not necessary.

Next, it is confirmed whether there is a print request (step 305). The print request is a print output request from the host PC 112 via the network, a copy output request via the operation unit, or the like. If there is no print request, it is confirmed whether there are repeated print requests. If a print request is detected, the requested number of prints is set in the reference register 202 (step 306). Then, the print completion flag 204 corresponding to the print request is cleared to 0 (step 307). Next, a printing instruction is started to the engine 111 (step 308). The print instruction refers to a series of processes for transmitting image data while transmitting / receiving a print command on the image bus. During the subsequent processing, the printing instruction is repeated until all the pages scheduled to be printed are printed. Note that image formation by the engine is performed in parallel with the printer controller 100, and paper feed, conveyance, fixing, paper discharge, and the like are performed in relation to the engine.
From here, it is a step of confirming the completion of printing for each sheet. The method for confirming the completion of printing is not particularly limited. For example, there is a method in which printing is completed when discharge completion is detected by a discharge detection sensor. When the completion of printing for each sheet is detected (step 309), the sub-counter 201 is incremented (added by 1) (step 310), and the value of the sub-counter 201 and the preset reference register 202 are checked to check the end of the print job. The value is compared (step 311). If they match, that is, if all the scheduled print sheets have been printed (step 311 is YES), the value of the current sub-counter 201 is added to the main counter 203 according to the print request (step 312), and at the same time, The print completion flag 204 is set to 1 and the processing from step 304 is repeated. If they do not match (NO in step 311), the process returns to step 309 to confirm the completion of printing.
If the completion of printing for each sheet is not detected in step 309, an error is detected before the completion of printing for each sheet due to paper jam detection or the expiration of the timer. Returning to the process from the time when the error occurred, if no error has occurred, the process returns to step 309 to confirm the completion of printing. The above process is a counter control method that can restore the counter value even when the power is turned off during printing.

FIG. 4 is a diagram illustrating an example of processing when the power is turned off during printing. In the figure, a CPU 101, an engine 111, an ASIC 102, and an IC card 110 are the same as those shown in FIG.
“Power-on” is the timing when the system power is turned on. For example, the main counter 203 at the time of power-on is “0x1000” (hexadecimal), and the print completion flags 204 are all “1”.
The CPU 101 reads the print completion flags 204 # 1 to #N. Here, it is assumed that the print completion flags 204 are all “1”, and the print job is not interrupted due to power interruption (the main counters # 1 to #N are all correct values). Next, the CPU 101 initializes both the reference register 202 and the sub-counter 201 to “0”. Here, the reference register 202 is in the high-speed nonvolatile memory area in the ASIC 102, but may be in the RAM 105 area.
Since there has been a print request from the host PC 112 (for example, an instruction to print 10 pages of files in monochrome), the CPU 101 writes “10” in the reference register 202. The reference register 202 becomes 0xA (decimal number “10” is hexadecimal number “A”). Next, the print completion flag 204 (# 1 in this case) for monochrome printing is cleared. # 1 of the print completion flag 204 is “0”.

After completing the above preparation, the CPU 101 instructs the engine 111 to print. Actually, a write command and image data are transferred. When the completion notification is received from the discharge sensor of the engine 111 every time printing of one sheet is completed, the value of the sub-counter 201 is incremented every time printing of one sheet is completed. The completion of printing may be other sensing and timing such as completion of transfer in addition to completion of paper discharge. Similarly, assume that printing is completed for the second and third sheets, and the power is shut off after the sub-counter 201 is rewritten to 0X3 (power off in the figure).
Next, when the power is turned on (second power-on in the figure), the CPU 101 reads all the print completion flags 204 as described above. It is detected that the print completion flag # 1 is “0”. Although there are N print completion flags, in general, only one of the print completion flags is controlled to be “0”. Therefore, the print completion flag 204 is read in order of # 1, # 2,. Reading may be terminated when the print completion flag (“0”) is confirmed or when all the print completion flags are confirmed to be “1”. As an exception, when a plurality of functions operate simultaneously and there are a plurality of print completion flags, it is necessary to read and check all N print completion flags (not shown).
In this example, since the print completion flag # 1 is cleared, the CPU that knows that the counter value of the main counter # 1 has not been updated adds the value of the sub-counter 201 to the main counter 203. The main counter value is updated. At the same time, the print completion flag # 1 is set to “1”. Since the main counter # 1 and the print completion flag # 1 are stored in the same word, the main counter # 1 and the print completion flag # 1 can be changed by one access to the low speed memory. Then, the reference register 202 and the sub-counter 201 are initialized, and the next print request is awaited.

1 is a diagram illustrating a system configuration example of an image forming apparatus according to the present invention. The figure explaining the structure of the counter of this invention. 6 is a flowchart showing counter processing in the image forming apparatus of the present invention. The figure which shows the example of a process when a power supply is turned off during printing.

Explanation of symbols

100 printer controller, 101 CPU, 102 ASIC, 103 IC card I / F, 104 ROM, 105 RAM, 106 expansion connector, 107 operation unit I / F, 108 engine I / F, 109 network I / F, 110 IC card, 111 Engine, 112 Host PC, 201 Sub-counter, 202 Reference register, 203 Main counter, 204 Print completion flag

Claims (7)

In an image forming apparatus having a counting means for counting the number of printed sheets,
The counting means includes a reference register for storing a numerical value for determining the end of the print job;
Provided in each non-volatile memory,
A sub-counter that is incremented each time one sheet is output during print job processing,
A print completion display means for indicating the completion of printing when the end of the print job is determined with reference to the reference register and the sub-counter, and a main counter for holding the cumulative number of printed sheets of the image forming apparatus,
An image characterized in that when the print job is completed and when the print completion display means does not indicate completion at power-on, the value of the sub-counter is added to the main counter to count the number of printed sheets. Forming equipment.   The image forming apparatus according to claim 1, wherein the main counter and the print completion display unit are configured by a non-volatile memory that is slower than the sub-counter.   2. The image forming apparatus according to claim 1, wherein the sub-counter and the reference register are configured in an ASIC. The operation of the main counter and the printing completion display means an image forming apparatus, according to any one of claims 1 to 3, wherein the counting in association with another or the type of output paper color / monochromatic image Forming equipment. The main counter and the printing completion display means an image forming apparatus according to any one of claims 1 to 4, characterized in that is constituted by a removable non-volatile memory. Said provided corresponding to the number of jobs simultaneously function of the sub-counter and the reference register image forming apparatus, an image forming apparatus according to any one of claims 1 to 5, wherein the counting in association with each job . A method for counting the number of printed sheets in an image forming apparatus, wherein the number of printed sheets is set in a reference register at the start of a print job, a value indicating incomplete is set in a print completion flag provided in a nonvolatile memory, and each time one sheet is output, A sub-counter provided in the non-volatile memory is incremented, and when the value of the sub-counter becomes equal to the value of the reference register, the value of the sub-counter is provided in the non-volatile memory that holds the cumulative number of printed sheets of the image forming apparatus. Add to the main counter, set a value indicating completion to the print completion flag, and simultaneously set the sub-counter to zero,
In addition, when the image forming apparatus is turned on, the print completion flag is referred to. When a value indicating incomplete is set, the value of the sub-counter is added to the main counter to add the uncounted number of sheets. A method for counting the number of printed sheets.

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