Abstract:
An image forming apparatus which forms an image and exchanges information to and from an external apparatus includes a replacement detection unit to detect that a consumable constituting the image forming apparatus is replaced, a temporary information storage unit to store, when the replacement detection unit detects that the consumable is replaced, replacement achievement information of the consumable as temporary information indicating that the replacement is temporary into a storage unit, and a formal information storage unit to store, when a specified condition is established, the temporary information as formal information indicating that the replacement is confirmed into the storage unit.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a technique to properly grasp the replacement date of each part in order to create a maintenance plan of a product including plural parts. 
         [0003]    2. Description of the Related Art 
         [0004]    In an image forming apparatus such as a printer or a facsimile, replacement parts such as a photoconductive drum and toner are used. Hitherto, the replacement timing of these replacement parts is determined based on the experience and intuition of a service man. Thus, there has been a problem that prediction accuracy of the replacement timing is low. 
         [0005]    Then, information relating to the consumption degree of each replacement part of an image forming apparatus is transmitted to an external service center by using external communication means provided in the image forming apparatus. At the service center, the replacement timing of each replacement part is predicted based on the transmitted information, and a maintenance plan of the product is created (JP-A-7-246758, JP-A-11-179971). 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    According to a first aspect of the invention, an image forming apparatus which forms an image and exchanges information to and from an external apparatus includes a replacement detection unit to detect that a consumable constituting the image forming apparatus is replaced, a temporary information storage unit to store, when the replacement detection unit detects that the consumable is replaced, replacement achievement information of the consumable as temporary information indicating that the replacement is temporary into a storage unit, and a formal information storage unit to store, when a specified condition is established, the temporary information as formal information indicating that the replacement is confirmed into the storage unit. 
         [0007]    According to a second aspect of the invention, an image forming method of an image forming apparatus which forms an image and exchanges information to and from an external apparatus includes a replacement detection step of detecting that a consumable constituting the image forming apparatus is replaced, a temporary information storage step of storing, when it is detected at the replacement detection step that the consumable is replaced, replacement achievement information of the consumable as temporary information indicating that the replacement is temporary into a storage unit, and a formal information storage step of storing, when a specified condition is established, the temporary information as formal information indicating that the replacement is confirmed into the storage unit. 
         [0008]    Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0009]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. 
           [0010]      FIG. 1  is a perspective view showing a rough shape of an image forming apparatus to which the invention can be applied. 
           [0011]      FIG. 2  is a block diagram showing a structure of a copy function of an MFP. 
           [0012]      FIG. 3  is a block diagram showing a structural example of the MFP. 
           [0013]      FIG. 4  is a system structural view showing the outline of a maintenance method using the MFP. 
           [0014]      FIG. 5  is a flow diagram showing a rough processing procedure of a case where toner replacement is performed by a user. 
           [0015]      FIG. 6  is a view showing the content of a replacement history information table. 
           [0016]      FIG. 7  is a flow diagram showing a rough processing procedure at a normal time when abnormality does not occur. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    Hereinafter, an embodiment of the invention will be described while an image forming apparatus (MFP: Multi Function Peripheral)  201  is used as an example. 
         [0018]    The MFP  201  is a digital multifunction machine for comprehensively using functions of various office equipments, such as an image reception function of a FAX, an image reception function of E mail, and a print image reception function of a network, in addition to scanning, reading and copying an image with a specified resolution and sheet size. 
         [0019]      FIG. 1  is a perspective view showing a rough shape of the image forming apparatus to which the invention can be applied. 
         [0020]    The MFP  201  includes a print unit  1 , a sheet tray  3 , a scan unit  5 , an auto feed unit  7  and an operation panel  9  provided with an LCD  8 . 
         [0021]    The print unit  1  outputs image information as an output image called a hard copy or a printout. The sheet tray  3  supplies an output medium as a sheet of an arbitrary size used for image output to the print unit  1 . The scan unit  5  captures image information as image data from an original document. The auto feed unit  7  sends the original document whose reading is completed from a read position to a discharge position, and guides a next original document to the read position. The operation panel  9  is an instruction input unit for instructing an operation of the MFP  201 , such as a start of image formation in the print unit  1  or a start of reading of the image information of the original document by the scan unit  5 . The operation panel  9  is provided with the LCD  8  for inputting instructions and displaying information to the operator. 
         [0022]    Further, the MFP  201  is connected to a not-shown network and a communication line and can receive image data by FAX, Email or the like. 
         [0023]      FIG. 2  is a block diagram showing a structure of a copy function of the MFP  201 . 
         [0024]    The MFP  201  includes a control unit  10 , a photoconductive drum  102 , a charging unit  103 , a scanning exposure unit  104 , a developing unit  105 , a transfer charger  106 , a peel charger  107 , a cleaner  108 , a paper feed unit  109 , a sheet transport unit  110 , a fixing unit  111 , a paper discharge unit  112  and a paper discharge tray  114 . 
         [0025]    The photoconductive drum  102  rotates in a sub-scanning direction as a peripheral direction of the photoconductive drum  102 . The charging unit  103  is disposed in the vicinity of the periphery of the photoconductive drum  102 . The charging unit  103  uniformly charges the surface of the photoconductive drum  102 . The scanning exposure unit  104  turns on/off a light according to an image signal while scanning a semiconductor laser in the scanning exposure unit  104 . The laser light emitted from the semiconductor laser becomes the light scanning in a main scanning direction as a rotation axis direction of the photoconductive drum  102  by a deflector such as a polygon mirror. The laser light is irradiated onto the photoconductive drum  102  by an optical system such as a lens. When the laser light is irradiated to the charged photoconductive drum  102 , the potential of an irradiated part is reduced and an electrostatic latent image is formed. 
         [0026]    The developing unit  105  applies a developer to the photoconductive drum  102  to form a toner image on the photoconductive drum  102 . On the other hand, the sheet tray  3  is provided at the bottom of the MFP  201 . A paper feed roller  115  separates sheets  130  in the sheet tray  3  one by one and sends them to the paper feed unit  109 . The paper feed unit  109  supplies the sheet  130  to the transfer position of the photoconductive drum  102 . The transfer charger  106  transfers the toner image to the supplied sheet  130 . The peel charger  107  peels the sheet  130  from the photoconductive drum  102 . 
         [0027]    The sheet  130  on which the toner image is transferred is transported by the sheet transport unit  110 . The fixing unit  111  fixes the toner image to the sheet  130 . The paper discharge unit  112  discharges the sheet  130  on which the image is printed to the paper discharge tray  114 . 
         [0028]    After the transfer of the toner image to the sheet  130  is completed, a residual toner on the photoconductive drum  102  is removed by the cleaner  108 . The photoconductive drum  102  returns to the initial state and is put in a waiting state of next image formation. 
         [0029]    The image formation operation is continuously performed by repeating the above process operation. 
         [0030]      FIG. 3  is a block diagram showing a structural example of the MFP  201 . 
         [0031]    The MFP  201  further includes a control unit  10 , a ROM  11 , a RAM  12 , a network control unit  17  and an inner storage device (HDD)  19  as well as the print unit  1 , the sheet tray  3 , the scan unit  5 , the LCD  8  and the operation panel  9 . The respective parts are connected through a system bus. 
         [0032]    The control unit  10  controls the respective hardware parts connected through the system bus. The ROM  11  stores various control programs necessary for the MFP  201  to operate. The RAM  12  is a buffer memory to temporarily store data generated at the time of execution of a control program. 
         [0033]    The network control unit  17  is an interface for exchanging information through a network such as the Internet. The HDD  19  is a nonvolatile storage medium installed inside the MFP  201 . The HDD  19  records history information relating to part replacement. 
         [0034]      FIG. 4  is a system structural view showing the outline of a maintenance method using the MFP of the embodiment of the invention. 
         [0035]    Plural service men  202  maintain plural MFPs  201  installed at plural users while one service center  203  is used as a base. 
         [0036]    Related art maintenance methods include a preventive maintenance (PM) and an emergency maintenance (EM). In the PM, the service man  202  visits the MFP  201  as the maintenance object at a periodic timing set for each MFP and performs replacement of consumables, cleaning, and operation confirmation of the MFP  201 . In the EM, in the case where a failure accidentally occurs, a service call from the user is received and a visit is made for the repair of the MFP  201 . 
         [0037]    At the time of completion of the work, the service man  202  transmits maintenance history data to a maintenance plan system  200  provided in the service center  203  through the network control unit  17  of the MFP  201 . When the MFP  201  has no communication function, the service man  202  returns to the service center  203  and inputs maintenance history data to the maintenance plan system  200  from a working record summarized as a report of the maintenance work. The maintenance history data is stored in a storage means  205 . 
         [0038]    Besides, at a set periodic communication time (for example, 10 o&#39;clock every day), the MFP  201  transmits data relating to the use state to the maintenance plan system  200 . The data relating to the use state are stored in the storage means  205 . 
         [0039]    In the maintenance plan system  200 , a failure history analysis means  204  calculates a failure rate distribution by using Weibull distribution for each consumable based on the past maintenance history data, and performs failure prediction based on the failure rate distribution. A maintenance plan means  206  calculates a next visit time and a list of consumables to be replaced at that time from the data relating to the use state of the MFP  201  collected through the network control unit  17 . 
         [0040]    From the viewpoint of preventing a failure from occurring and keeping the reliability of the MFP  201  by shortening a failure time, it is considered to be desirable that with respect to a consumable such as toner, the user can voluntarily replace it without replying on the service man  202 . Thus, with respect to a specified consumable, a mechanism is designed so that the user can easily replace it, it is automatically detected that the consumable is replaced, and maintenance history data indicating the replacement is automatically transmitted to the maintenance plan system  200 . 
         [0041]    However, in the case where the MFP  201  is constructed as stated above, it is necessary to prevent erroneous data from being transmitted to the maintenance plan system  200 . Since the user who performs the replacement work is not always a skilled person differently from the service man  202 , it is not ensured that the replacement is certainly performed in an expected state. Further, in the case where erroneous maintenance history data is transmitted, the accuracy of a maintenance plan created by the maintenance plan system  200  is reduced, and the reliability of the service center  203  and the MFP  201  is reduced. 
         [0042]      FIG. 5  is a flow diagram showing a rough processing procedure of a case where toner replacement is performed by the user. The control unit  10  of the MFP  201  performs a relevant program and this processing is realized. 
         [0043]    In the case where the MFP  201  detects toner empty, at step S 01 , the control unit  10  displays a warning of the toner empty on the LCD  8  of the operation panel  9 , and urges the user to replace. Incidentally, the toner empty may be informed to an administrator by using communication means via electronic mail. 
         [0044]    At step S 02 , the process waits for the replacement of toner is performed by the user. When the user takes out an empty cartridge and sets a new cartridge, the MFP  201  automatically detects that the toner is replaced. At step S 03 , it is checked whether it is detected that the toner replacement is performed. In the case of Yes at step S 03 , that is, in the case where the MFP  201  detects the toner replacement, at step S 04 , a replacement history information table  30  stored in the HDD  19  is updated. 
         [0045]      FIG. 6  is a view showing the content of the replacement history information table  30 . 
         [0046]    The replacement history information table  30  includes “present date”, “accumulated counter value”, “consumable replacement flag”, “consumable replacement determination method”, “consumable replacement reference value”, “consumable replacement date”, “consumable replacement time counter value”, “consumable temporary replacement date”, and “consumable temporary replacement time counter value”. Incidentally, the “consumable replacement flag” to the “consumable temporary replacement time counter value” are provided for each consumable. 
         [0047]    The present year, month, day and time are stored in the “present date”. The accumulation of counter values as the number of times of copying in the MFP  201  is recorded in the “accumulated counter value”. Incidentally, A4 copy/print is counted as 1, A3 copy/print is counted as 2, and the counter value represents how many sheets in A4 size are outputted. 
         [0048]    The “consumable replacement flag” is a flag to indicate that the replacement of the relevant consumable is in a temporary state. That is, in a state where the replacement is not confirmed, the flag is set to ON, and when the replacement is confirmed, the flag is set to OFF. The “consumable replacement determination method” represents a condition used for confirming the replacement of the consumable. For example, when it is “0”, a counter value is used for a conditional expression of determination. When it is “1”, a date is used for the conditional expression of determination. The “consumable replacement reference value” represents a threshold value for confirmation of the replacement of the consumable. 
         [0049]    A confirmed value of the date when the consumable is replaced is stored in the “consumable replacement date”. A confirmed value of the counter value when the consumable is replaced is stored in the “consumable replacement time counter value”. The date when the user replaces the consumable is stored in the “consumable temporary replacement date”. The counter value at the time when the consumable is replaced by the user is stored in the “consumable temporary replacement time counter value”. 
         [0050]    Incidentally, in the replacement history information table  30  of  FIG. 6 , although not shown in the drawing, past history information relating to the replacement of consumables is recorded. 
         [0051]    Referring back to  FIG. 5 , at step S 04 , the control unit  10  turns ON the “consumable replacement flag” of the relevant consumable of the replacement history information table  30 . The present date and the present counter value of the MFP  201  are stored in the “consumable temporary replacement date” and the “consumable temporary replacement time counter value”, respectively. 
         [0052]    At step S 05 , it is checked whether there is an image forming job being executed at present. In the case of Yes at step S 05 , that is, in the case where there is an image forming job being executed at present, at step S 06 , the image forming job is executed and the process proceeds to step S 07 . In the case of No at step S 05 , that is, in the case where there is no image forming job being executed at present, the process proceeds to END without executing a subsequent processing. 
         [0053]    At step S 07 , it is checked whether the relevant consumable is being temporarily replaced. In the case of Yes at step S 07 , that is, in the case where the “consumable replacement flag” of the relevant consumable in the replacement history information table  30  is “ON”, at step S 08 , it is checked whether the specified condition for confirming the replacement of the consumable is satisfied. 
         [0054]    For example, when the “consumable replacement determination method” is “0”, it is checked whether (“accumulated counter value”—“consumable temporary replacement time counter value”) exceeds the counter value of “consumable replacement reference value”. When the “consumable replacement determination method” is “1”, it is checked whether (“present date”—“consumable temporary replacement date”) exceeds the date of the “consumable replacement reference value”. 
         [0055]    In the case of Yes at step S 08 , that is, in the case where the specified condition is satisfied, at step S 09 , the temporary replacement information is updated to formal information. That is, the “consumable replacement flag” is turned “OFF”, and the “consumable temporary replacement date” and the “consumable temporary replacement time counter value” are copied to the “consumable replacement date” and the “consumable replacement time counter value”, respectively. At step S 10 , the “consumable replacement date” and the “consumable replacement time counter value”, together with information to specify the relevant consumable, are transmitted to the maintenance plan system  200  of the service center  203 . 
         [0056]    Here, in the case of No at step S 05 , that is, in the case where there is no image forming job being executed at present, the processing subsequent to step S 07  is not executed because the process proceeds to END without executing the subsequent processing. Thereafter, the processing subsequent to step S 07  is executed when an image forming job is executed in a normal state in which abnormality does not occur. 
         [0057]      FIG. 7  is a flow diagram showing a rough processing procedure of a case where an image forming job is executed in a normal state where abnormality does not occur. 
         [0058]    When the image forming job occurs, at step S 16 , the image forming job is executed, and the process proceeds to step S 17 . 
         [0059]    At step S 17 , it is checked whether the relevant consumable is being temporarily replaced. In the case of Yes at step S 17 , that is, in the case where the “consumable replacement flag” of the relevant consumable in the replacement history information table  30  is “ON”, at step S 18 , it is checked whether a specified condition for confirming the replacement of the relevant consumable is satisfied. Since the processing of step S 18  is similar to the processing of step S 08 , its explanation will be omitted. 
         [0060]    Then, in the case of Yes at step S 18 , that is, in the case where the specified condition is satisfied, at step S 19 , the temporary replacement information is updated to formal information. Since the processing of step S 19  is similar to the processing of step S 09 , its explanation will be omitted. 
         [0061]    At step S 10 , the “consumable replacement date” and the “consumable replacement time counter value”, together with information to specify the relevant consumable, are transmitted to the maintenance plan system  200  of the service center  203 . 
       Second Embodiment 
       [0062]    Next, a second embodiment of the invention will be described. 
         [0063]    This embodiment is a modified example of the first embodiment, and its basic system structure is the same. Hereinafter, the same portion as the portion already explained in the first embodiment is denoted by the same reference numeral and its explanation will be omitted. 
         [0064]    In this embodiment, an MFP  201  includes a cartridge in which a photoconductive drum  102 , a charging unit  103 , a cleaner  108 , a developing unit  105  and the like are integrally unitized, and the cartridge can be attached to and detached from a main body. 
         [0065]    In the cartridge in which various parts are integrated as stated above, when any one of the parts constituting the cartridge is broken, the necessity of replacement is caused. Then, in this embodiment, the cartridge is regarded as one part and is handled. 
         [0066]    Differing from the first embodiment, the MFP  201  does not include means for detecting the life of the cartridge. Then, at the time of periodic communication, the MFP  201  downloads information of “cartridge replacement date” stored in storage means  205  of a maintenance plan system  200 , and displays a message of cartridge replacement on an operation panel  9  provided in the MFP  201 . The procedure of cartridge replacement work by the user subsequent to this is the same as that of the first embodiment. 
         [0067]    Since the detachment and attachment of the cartridge are easy, the user can replace it, and it is desirable that the replacement of a consumable whose replacement is easy as stated above is performed at the user side to the extent possible from the viewpoint of the cost of maintenance work and the improvement of efficiency. 
         [0068]    By this, maintenance work can be arranged such that, with respect to a consumable which can be replaced at the user side, but the replacement work is performed at the user side without being visited by a service man  202 , and with respect to a consumable whose replacement is difficult at the user side, the service man  202  visits, whereby the working efficiency of maintenance work can be improved, and further, the accuracy of a maintenance plan can be kept. 
         [0069]    According to the embodiment described above, even in the case where the user temporarily detaches a consumable and again attaches a consumable, it is possible to prevent that erroneous replacement information is adopted. 
         [0070]    For example, when a warning of toner empty is issued, there is a case where a small amount of toner remains in the cartridge. Then, there is a case where printing becomes possible when the cartridge is set again after it is shaken. At this time, there has been a fear that in the MFP  201 , it is determined that a new cartridge is set, update of information such as replacement date is immediately performed, and erroneous replacement information is transmitted to the maintenance plan system  200 . 
         [0071]    According to this embodiment, in the case where a sufficient number of times or more is counted by the print counter, or a specified period has passed, it is determined that the toner cartridge is normally replaced, and the temporary replacement date is made the formal replacement date. When the update of the normal replacement date is performed, the information is transmitted to the service center  203 . 
         [0072]    By this, the maintenance plan system  200  calculates a next replacement scheduled date based on the correct replacement information, so that it becomes possible to accurately calculate the predicted date, and the improvement of maintenance plan accuracy can be expected. 
         [0073]    According to the procedure of the embodiment, in the case where the toner empty is detected again before the number of times reaches a specified value, the user is again urged to replace, and the point of time can be again set as the temporary replacement date. 
         [0074]    Incidentally, in this embodiment, although the description has been made while using the toner replacement as an example, the invention can be applied to replacement of a consumable other than toner. 
         [0075]    Besides, even in the case where the MFP  201  does not have the function to detect the life of the consumable or the consumption state, information relating to the life of the consumable or the consumption state is acquired from the service center, and measures can be taken. 
         [0076]    Incidentally, in this embodiment, although the maintenance method uses the MFP  201  and the maintenance plan system  200 , the maintenance plan system  200  may not be used, and the MFP  201  may have the function of the maintenance plan system  200 . 
         [0077]    Further, various methods may be applied to the life prediction of each consumable. In this embodiment, although the life prediction is performed based on the failure rate distribution using the Weibull distribution, a method other than the Weibull distribution may be used. Besides, the life may be directly calculated by arithmetic operation from the past failure history information. 
         [0078]    Besides, the invention can be applied to an apparatus other than the image forming apparatus. 
         [0079]    Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.