JP5077291B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus having an image forming member that deteriorates in use and with time, such as a photoconductor, a developing device, and a process unit including these.

  In an image forming apparatus, an image forming member such as a photoconductor, a developing unit, and a process unit including these gradually deteriorates with use, and the image quality gradually decreases accordingly. For this reason, an image forming member that has deteriorated to some extent is replaced with a new one, and a stable operation of the apparatus is ensured over a long period of time.

  In many of the conventional image forming apparatuses, two thresholds are provided with respect to the member replacement timing. One of the threshold values is a limit value that can guarantee image quality. When the degree of deterioration of the member reaches this threshold value, for example, a display prompting replacement of the member is made on the display panel. Another threshold value is a limit value for use of the member. When the degree of deterioration of the member reaches this threshold value, a display forcing the replacement of the member is made, and control is performed to disable image formation thereafter.

  Most users of the image forming apparatus immediately replace the member in accordance with the display prompting replacement of the member.

  However, acceptable image quality varies depending on the user, and replacing a member with a new one, despite the fact that there is no sudden deterioration in image quality, appears to be uneconomical for users who are not concerned about image quality. It was.

JP 2000-89625 A

  The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide an image forming apparatus capable of selecting and setting an image forming member replacement notification time according to a user's request.

According to the present invention, as the deterioration degree of the image forming member, the first threshold value indicating the predetermined deterioration degree, the second threshold value indicating the deterioration degree at which the deterioration has progressed from the first threshold value, and the first threshold value to the second threshold value. And the image quality priority mode and the economy priority mode can be selected and set. When the image quality priority mode is selected and set, the deterioration degree of the image forming member is the first threshold value. If the economic priority mode is selected and set, the user is informed to the maintenance manager of the apparatus when the degree of deterioration of the image forming member reaches the first threshold value. An image forming apparatus is provided that performs notification for preparation for replacement of the image forming apparatus and notifies the user of replacement of the member when the degree of deterioration of the image forming member reaches a third threshold value.

  From the viewpoint of performing stable image formation, image formation may be disabled when the degree of deterioration of the image forming member reaches the second threshold value.

  As an index of the degree of deterioration of the image forming member, it is preferable to use at least one of the number of image formations and the image formation time. In this specification, “the number of image formations” refers to the cumulative number of image formations, and “image formation time” refers to the cumulative time during which the member is driven. The “image quality priority mode” prompts the replacement of the image forming member when the degree of deterioration is small compared to the “economic priority mode” so that the risk that the deterioration of the image forming member affects the image is reduced. The mode to be set. The “economic priority mode” is a mode in which replacement of the image forming member is promoted at a point of time when the degree of deterioration is large compared to the “image quality priority mode”, and the usage period of the image forming member is set longer. is there.

  In the image forming apparatus of the present invention, the image quality priority mode and the economy priority mode can be selected and set, and the member replacement notification timing can be changed depending on the mode to be selected. Can also respond.

In addition, even when the economy priority mode is selected and set in a period shorter than the case of the image quality priority mode, the period from when the notification of member replacement is made until the second threshold value that is the service life of the member is reached, the degree of degradation of the image forming member reaches Then the first threshold value, so to notify the exchange preparation of its members to the maintenance of the apparatus, can the exchange preparation of obtaining such a new member in advance, so that can be carried out smoothly member exchange become.

  If image formation becomes impossible when the degree of deterioration of the image forming member reaches the second threshold, image defects due to breakage of the member can be prevented, and image formation can be performed stably.

  When at least one of the number of image formations and the image formation time is used as an index of the deterioration degree of the image forming member, the deterioration degree of the image forming member can be accurately grasped.

1 is a schematic diagram illustrating an example of a printer that is an image forming apparatus according to the present invention. FIG. 2 is a schematic block diagram illustrating a configuration of the printer in FIG. 1. It is a figure which shows the timing which performs the replacement | exchange promotion display and replacement display of a member. It is a table | surface which shows the example of the content of the replacement | exchange promotion display of a member, and an exchange display. It is a figure which shows the example of a display in a display panel. It is a flowchart which shows the example of control which performs replacement | exchange promotion display and replacement display of a member.

  Hereinafter, the image forming apparatus according to the present invention will be described in more detail with reference to the drawings. However, the present invention is not limited to these embodiments.

  FIG. 1 is a schematic diagram showing an example of an image forming apparatus according to the present invention. The image forming apparatus in FIG. 1 is a tandem digital color printer (hereinafter, simply referred to as “printer”). Of course, in addition to a printer, the present invention can also be applied to a copying machine having a scanner, a facsimile, or a multi-function machine having these functions combined. In the following, when it is necessary to clarify whether the device or member to be described is yellow (Y), magenta (M), cyan (C), or black (K), The description will be made by adding the characters “(Y)”, “(M)”, “(C)”, and “(K)” to the reference numerals, and otherwise omitting those characters.

  The printer 1 includes an intermediate transfer belt (intermediate transfer member) 11 at a substantially central portion inside thereof. The intermediate transfer belt 11 is wound around the outer periphery of the roller 12, the tension roller 13, and the guide rollers 14 and 15, and is driven to rotate counterclockwise. The tension roller 13 is slidably attached to the outside and is urged by the pressing spring S from the inside to the outside of the intermediate transfer belt 11. Thus, the intermediate transfer belt 11 is always in a tensioned state.

  Below the lower horizontal portion of the intermediate transfer belt 11, four image forming portions 2Y, 2M, 2C, and 2B respectively corresponding to yellow (Y), magenta (M), cyan (C), and black (B) colors. Are arranged in this order along the intermediate transfer belt 11. Each image forming unit 2Y, 2M, 2C, 2B has a photosensitive drum (image carrier) 21Y, 21M, 21C, 21B, respectively. Around each of the photosensitive drums 21Y, 21M, 21C, and 21B, the chargers 22Y, 22M, 22C, and 22B, the print head portions 23Y, 23M, 23C, and 23B, and the developing device (in the order along the rotation direction). Developing means) 24Y, 24M, 24C, 24B and cleaners (cleaning means) 25Y, 25M, 25C, 25B are arranged, respectively. The print head portions 23Y, 23M, 23C, and 23B are composed of a large number of LEDs arranged in the main scanning direction parallel to the axial direction of the photosensitive drum. The photosensitive drums 21Y, 21M, 21C, and 21B and the developing devices 24Y, 24M, 24C, and 24B may constitute a process unit that is integrated for each color.

  Further, primary transfer rollers (primary transfer members) 30Y, 30M, 30C, and 30B are provided at positions facing the respective photosensitive drums 21Y, 21M, 21C, and 21B with the intermediate transfer belt 11 interposed therebetween. A secondary transfer roller 16 is pressed against the portion of the intermediate transfer belt 11 supported by the roller 12. A nip portion between the secondary transfer roller 16 and the intermediate transfer belt 11 becomes a secondary transfer region 17. The toner image formed on the intermediate transfer belt 11 in the secondary transfer region 17 is transferred to the conveyed paper (recording member) P.

  A paper feed cassette 91 is detachably disposed at the bottom of the printer 1. The sheets P stacked and housed in the sheet feeding cassette 91 are pulled out one by one from the uppermost one by the rotation of the sheet feeding roller 92 and sent out to the transport path 93. The conveyance path 93 extends from the paper feed cassette 91 to the paper discharge tray 98 through the nip portion of the timing roller pair 94, the secondary transfer region 17, and the fixing unit 95. The paper P sent out from the paper feed cassette 91 is conveyed to the timing roller pair 94 and is sent out to the secondary transfer area 17 at a predetermined timing.

  The fixing unit 95 has a hollow cylindrical shape, and includes a fixing roller 96 having a halogen heater H therein, and a pressure roller 97 that is pressed against the fixing roller 96 and rotates. A nip portion between the fixing roller 96 and the pressure roller 97 through which the sheet P on which the toner image is secondarily transferred passes is a fixing region.

  A schematic operation of the printer 1 having such a configuration will be described. First, in the full color mode for outputting a color image, when an image signal is input from an external device (for example, a personal computer) to an image signal processing unit (not shown) of the printer 1, the image signal processing unit converts the image signal to yellow, A digital image signal color-converted to cyan, magenta, and black is created, and this signal is transmitted to the LED drive circuit for the print head. This drive circuit performs exposure by causing the print head units 23Y, 23M, 23C, and 23B of the image forming units 2Y, 2M, 2C, and 2B to emit light based on the input digital signals. This exposure is performed with a time difference in the order of the print head portions 23Y, 23M, 23C, and 23B. Thereby, electrostatic latent images for the respective colors are formed on the surfaces of the respective photosensitive drums 21Y, 21M, 21C, and 21B.

  The electrostatic latent images formed on the photosensitive drums 21Y, 21M, 21C, and 21B are respectively developed by the developing devices 24Y, 24M, 24C, and 24B to become toner images of the respective colors. Then, the toner images of the respective colors are sequentially primary-transferred and superimposed on the intermediate transfer belt 11 that rotates counterclockwise in the drawing by the action of the primary transfer rollers 30Y, 30M, 30C, and 30B.

  The toner image formed on the intermediate transfer belt 11 in this way reaches the secondary transfer region 17 as the intermediate transfer belt 11 moves. On the other hand, the paper P sent out from the paper feed cassette 91 to the transport path 93 is transported to the secondary transfer region 17 by the timing roller pair 94 at the timing when the toner image reaches the secondary transfer region 17. A voltage having a polarity opposite to the charging polarity of the toner is applied to the secondary transfer roller 16. As a result, in the secondary transfer region 17, the superimposed color toner images are secondarily transferred collectively from the intermediate transfer belt 11 to the paper P. The toner remaining on the intermediate transfer belt 11 after the secondary transfer is collected by a belt cleaner (not shown).

  The sheet P onto which the toner image has been secondarily transferred is sent to the fixing unit 95 through the conveyance path 93, where the toner image is fixed on the sheet P by passing through the fixing region. Then, the paper P is discharged to the paper discharge tray 98.

  FIG. 2 is a block diagram showing a part of the control circuit of the printer 1. This control circuit includes a control unit 30 that controls the entire operation of the printer 1. The control unit 30 includes an image forming unit 2, an operation panel 31, a timer 32 for measuring the current time, a unit detection sensor 33 for detecting that the process unit is mounted on the apparatus main body, and an image for measuring and integrating the number of formed images. A formation counter 34, a determination unit 35 that determines whether or not the number of formed images exceeds a threshold value, a signal processing unit 36, and a memory 37 that stores image formation conditions and the like are connected. In addition, various information and signals necessary for image forming operation control are input to the control unit 30 from an unillustrated portion, and various information and signals necessary for image forming operation control are output to an unillustrated portion. The The operation panel 31 includes a display panel 311, various keys 312, a start button 313, and a mode selection setting button 314.

  The mode selection setting button 314 is preferably operable only by an apparatus maintenance manager (so-called serviceman). When the maintenance manager selects and sets the image quality priority mode or the economy priority mode from the operation panel 31 according to the user's request, a mode selection signal is transmitted to the control unit 30, and the time when the member replacement promotion display is performed is set. Either one threshold value or the third threshold value is set. For example, when the number of image formations integrated by the image formation counter 34 exceeds the set threshold value, the control unit 30 displays a member replacement promotion display on the display panel 311.

  FIG. 3 shows a time chart of the member replacement display, and FIG. 4 shows the display contents. First, a case where the image quality priority mode is selected and set will be described. As understood from FIG. 3, in the case of the image priority mode, two threshold values, that is, a first threshold value and a second threshold value are related to the member replacement display. When the degree of deterioration of the image forming member reaches the first threshold value, a display prompting member replacement is displayed on the display panel. For example, as shown in FIG. 5 (a), a message such as “Unit replacement time is approaching. Replace the unit.” Is displayed in words that directly indicate the meaning of prompting member replacement. When such a member replacement promotion display is made, the user normally performs member replacement immediately. When the member is replaced, the image forming counter 33 (shown in FIG. 2) for measuring the degree of deterioration is reset to zero. On the other hand, image formation is possible even if member replacement is not performed after reaching the first threshold. When the image formation is continued without replacing the member and the degree of deterioration reaches the second threshold value, a display for forcibly replacing the member is displayed on the display panel. For example, as shown in FIG. 5B, a display such as “The unit has come to be replaced. Replace the unit.” Is displayed on the entire display panel. Further, no further image formation is possible unless the members are exchanged.

Next, a case where the economy priority mode is selected and set will be described. As understood from FIG. 3, in the case of the economy priority mode , three threshold values, that is, a first threshold value, a second threshold value, and a third threshold value are related to the member replacement display. First, when the degree of deterioration of the image forming member reaches the first threshold, unlike the image quality priority mode, a display for prompting the user to replace the member is not made. However, the maintenance manager of the printer is notified that the time for replacing the component is approaching. This is because the maintenance manager can prepare in advance for member replacement such as member ordering. Such a display for the maintenance manager is desirably a display that is not understood by the user of the apparatus, and is not a word that directly indicates the meaning of the member replacement preparation, but includes, for example, a symbol or a code. As an example, in FIG. 5C, an asterisk 39 is displayed at one corner of the display panel as a display for the maintenance manager. Of course, the display for the maintenance manager may be displayed on another display panel that the user cannot normally see.

  When the degree of deterioration reaches the third threshold value, a display prompting the user to replace the member is displayed on the display panel. At this time, for example, the display as shown in FIG. As in the case of the image quality priority mode, when such a member replacement promotion display is made, the member is normally replaced by the user, and the image forming counter for measuring the degree of deterioration is reset to zero. On the other hand, image formation is possible even if member replacement is not performed after reaching the third threshold. When the image formation is continued without replacing the member and the deterioration level reaches the second threshold value, for example, the display forcing the replacement as shown in FIG. Thus, no further image formation is possible unless the members are replaced.

  Examples of the image forming member in the present invention include a photosensitive drum, a developing device, a process unit including these, and the like. The degree of deterioration is the degree of deterioration of the image forming member, and can correspond to the degree of deterioration due to surface abrasion or the like in the case of a photoconductor, and the degree of consumption of developer in the case of a developing device.

  As an index of the degree of deterioration of the image forming member, it is preferable to use at least one of the number of image formations and the image formation time. Each threshold needs to be set individually depending on the type of member. The first threshold value indicating the predetermined deterioration level and the second threshold value indicating the deterioration level advanced from the first threshold value are appropriately determined in consideration of the material and type of the member. The third threshold value may be determined by subtracting from the second threshold value the degree of deterioration that progresses during image formation during a preparation period (usually about two weeks to one month) such as member ordering. For example, when the image forming member is a black photosensitive drum, and the image forming time is used as an index of the degree of deterioration of the photosensitive drum, the first threshold is 1500 minutes and the second threshold is 2000 minutes. Since the image formation time during the replacement preparation period is usually about 300 minutes, the third threshold value is 1700 minutes obtained by subtracting 300 minutes from the second threshold value 2000 minutes. Here, as the first to third threshold values, values obtained by experiments or the like may be stored in the memory 37 by input from the operation panel 31 or as settings at the time of shipment. Further, a storage device may be mounted on the image forming member, and the first to third threshold values stored in advance in the storage device may be read by the printer when the image forming member is mounted.

FIG. 6 is a flowchart showing a control example of the image forming apparatus according to the present invention. In the control example of the figure, the number of formed images is used as an index of the degree of deterioration. When the control is started, first, the image priority mode or the economy priority mode is selected and set (step S501). When image formation is performed (step S502), after the image formation number counter is accumulated (step S503), it is determined whether the image formation number counter N exceeds the first threshold (step S504). If the image formation number counter N is equal to or smaller than the first threshold (step S504), the process returns to step S502 to wait for image formation again. On the other hand, when the image formation number counter N exceeds the first threshold (step S504), it is next determined whether the selection setting mode is the image quality priority mode or the economic priority mode (step S505). When the selection setting mode is the economy priority mode, a member replacement preparation display is made for the maintenance manager (step S506). Then, it is next determined whether or not the image formation number counter N exceeds the third threshold value (step S507). If the image formation number counter N is equal to or smaller than the third threshold (step S507), the process returns to step S502 to wait for image formation again. On the other hand, when the image formation number counter N exceeds the third threshold value (step S507), a member replacement promotion display that can be understood by the user is displayed (step S508).

  Next, it is determined whether or not the image formation number counter N has exceeded the second threshold (step S510). If the image formation number counter N is less than or equal to the second threshold value, the process returns to step S502 to determine whether or not image formation has occurred. On the other hand, when the image formation number counter N exceeds the second threshold value, the member replacement display is made on the display panel (step S511). If the member is replaced according to this member replacement display (step S512), the image forming sheet number counter N is set to zero (step S513). On the other hand, if the member is not replaced in spite of the member replacement display (step S512), further image formation is disabled (step S515). Next, it is determined whether or not the image formation is finished (step S514). If the image formation is finished, the control is finished. If the image formation is not finished, the process returns to step S502 and the same control is repeated.

  Returning to step S505, if the selection setting mode is the image quality priority mode, a member replacement promotion display is made so as to be understood by the user (step S509). Then, the process proceeds to a step of determining whether or not the image formation number counter N has exceeded the second threshold (step S510), and the subsequent steps are the same control as in the economical priority mode.

  The image forming apparatus according to the present invention is useful because it can select and set an image forming member replacement notification time in accordance with a user's request.

1 Printer (image forming device)
P paper (recording member)
11 Intermediate transfer belt (intermediate transfer member)
16 Secondary transfer roller (secondary transfer member)
21 Photosensitive drum (image carrier)

Claims (3)

As the deterioration level of the image forming member, a first threshold value indicating a predetermined deterioration level, a second threshold value indicating a deterioration level that has progressed more than the first threshold value, and a first threshold value to a second threshold value are set. 3 threshold values can be set, and the image quality priority mode and economic priority mode can be selected and set.
When the image quality priority mode is selected and set, the user is informed of the replacement of the member when the degradation degree of the image forming member reaches the first threshold,
When the economic priority mode is selected and set, when the degree of deterioration of the image forming member reaches the first threshold value, the maintenance manager of the apparatus is notified to prepare for replacement of the member, and the image forming member An image forming apparatus that notifies a user of replacement of a member when the degree of deterioration reaches a third threshold value. The deterioration of the image forming member reaches the second threshold value, the image forming apparatus according to claim 1, disabling the image formation. As an index of the degradation degree of the image forming member, image forming apparatus according to claim 1 or 2, wherein using at least one of the number of image formation and an image forming time.