JP2014002233A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of predicting the occurrence of change in image density and reduction in resolution during image formation, and preventing the occurrence of them.SOLUTION: An image forming apparatus includes: an electrophotographic photoreceptor 101; latent image forming means for forming an electrostatic latent image on the electrophotographic photoreceptor, developing means for visualizing the electrostatic latent image formed by the latent image forming means, using toner; transfer means for transferring the image visualized by the developing means to a medium for transfer; and cleaning means for removing a toner remaining on the surface of the electrophotographic photoreceptor. The image forming apparatus further includes: electrophotographic photoreceptor temperature adjustment means capable of adjusting a temperature of the electrophotographic photoreceptor; torque measurement means 113 for measuring a driving torque value of the electrophotographic photoreceptor; and means for measuring the driving torque value of the electrophotographic photoreceptor, the driving torque value being used when the image has been formed by changing the temperature of the electrophotographic photoreceptor, and storing the degree of deterioration and/or a torque value of the electrophotographic photoreceptor calculated on the basis of a change in the torque value.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus that can prevent image quality defects from occurring in a copying machine, a laser printer, a normal facsimile, and the like and can output a high-quality image over a long period of time.
Specifically, it detects information relating to image density and / or image resolution reduction accompanying a change in surface physical properties of the electrophotographic photosensitive member used in the image forming apparatus, accumulates the detected information, and causes failure of the electrophotographic photosensitive member. It is possible to prevent the occurrence of image quality defects by predicting the timing and issuing an alarm to the user before image quality defects occur or by appropriately processing the electrophotographic photosensitive member as necessary. The present invention relates to a possible image forming apparatus.

  In recent years, development of miniaturization, ultra-long life, high image quality and high speed has been accelerated in response to the demand for space-saving, maintenance-saving, and high-functionality of image forming apparatuses using electrophotography. In addition, image forming apparatuses that embody them are released by various companies.

In particular, image quality has improved to the level of plate-making printing used for commercial printing, and printing business that can respond to on-demand at low cost due to high speed, downsizing, easy maintenance, and low maintenance. A new commercial printing business is being created.

In the commercial printing business, it is necessary to cope with mass printing capable of maintaining high image quality, and image defects tend to directly lead to profit loss. Therefore, there is a growing demand for higher image quality and higher image quality than ever.

(Image density / resolution reduction)
One of the image defects that are particularly problematic is an image density change. Image defects due to changes in image density are unlikely to be a major problem in monochromatic printing, but are very serious problems in color printing frequently used in commercial printing because they cause a change in color tone.

Further, a decrease in image resolution along with a change in image density is likely to cause a problem because it causes a decrease in character visibility and a decrease in edge definition.

Although there are several causes of these image density changes and resolution reductions, it is known that these image defects occur simultaneously due to changes in the surface physical properties of the electrophotographic photosensitive member used in the image forming apparatus.

  For example, since the surface resistance of the electrophotographic photosensitive member is reduced, the electric charge easily moves on the surface of the electrophotographic photosensitive member, and the electrostatic latent image formed in the electrostatic latent image forming process cannot be maintained for a long time. Density changes (particularly image density reduction) and resolution reduction occur.

(Functions required for image forming apparatus)
In order not to reveal such image defects, it is conceivable that “the image defect does not occur (does not cause the occurrence)” and “prevent the occurrence of the image defect”.

The former “no image defect occurs (does not cause the occurrence)” includes prevention (suppression) of reduction in surface resistance of the electrophotographic photosensitive member, which is considered to be the cause of the image defect.

Many studies have been reported on the prevention (suppression) of surface resistance reduction.
For example, in Japanese Patent No. 4387869 of Patent Document 1, an image indicating that the rate of change in capacitance of the electrophotographic photosensitive member is a certain value or less is used for the purpose of directly suppressing the change in surface resistance of the electrophotographic photosensitive member. It is disclosed that it is effective against a change in density and a decrease in resolution. Japanese Patent Application Laid-Open No. 2003-057855 of Patent Document 2 discloses that the water vapor permeability of the charge transport layer of the electrophotographic photosensitive member is set to a certain value or less. Is disclosed to be effective.

Many other prevention or suppression techniques have been disclosed, but all of them are techniques that are classified as extending the life, and can be said to be effective techniques for reducing the probability of occurrence of image defects.
However, although these conventional techniques can reduce the probability of occurrence of image defects, they are not techniques for completely preventing the occurrence of image defects (making the probability of occurrence zero), and the deterioration of the electrophotographic photoreceptor gradually proceeds. Therefore, it is impossible to prevent image degradation that can be seen when compared with the initial image.

As for the latter “preventing the occurrence of image defects”, there has been proposed a technique for recovering an electrophotographic photoreceptor that has changed due to accumulation of contaminants, etc., depending on the number of images formed and the period of use. . For example, Japanese Patent Application Laid-Open No. 2003-122222 of Patent Document 3 discloses a technique for removing surface deposits on an electrophotographic photosensitive member by using a high hardness member for the cleaning blade. Japanese Patent Laid-Open No. 2004-029059 discloses a technique related to a deposit removal sequence using a cleaning blade, and Japanese Patent Application Laid-Open No. 2007-233049 discloses a surface of an electrophotographic photosensitive member using a plurality of types of toner. A technique for refreshing is disclosed.

However, even if the deterioration time and life of the electrophotographic photosensitive member can be predicted to some extent, the degree of deterioration and the life time of the electrophotographic photosensitive member change depending on the usage situation and environment, so that an image defect occurs at a predetermined time. Even if preventive measures are taken, the image defects may occur.

Therefore, by using not only the image defect occurrence probability reduction technology and the electrophotographic photosensitive member recovery technology, but also the occurrence prediction technology for device defects such as image defects (hereinafter sometimes referred to as failures), the image It is considered that an image forming apparatus free from defects can be provided.
In other words, even if the usage situation or usage environment changes and the trouble occurrence time changes, it is possible to predict the trouble occurrence time, issue an alert to the user, and take appropriate measures to avoid the failure. This is effective in preventing any occurrences.

Regarding such failure prediction technology, for example, Japanese Patent Application Laid-Open No. 2005-17874 of Patent Document 6 acquires a plurality of types of information related to the state of the image forming apparatus, and an index from the acquired types of information. A technique is disclosed in which a value D is calculated, and a subsequent change in the state of the image forming apparatus is determined based on the time change data of the calculated index value D.
However, it relates to failure prediction for the entire image forming apparatus, and sufficient knowledge about specific index values for predicting a specific failure has not been disclosed. Control with an index value having high correlation with a specific failure to be solved is necessary.

In Japanese Patent No. 4672275 of Patent Document 7, the surface unevenness caused by scratches and filming is irradiated to the surface of the image carrier and the amount of diffusely reflected light is measured to detect the deterioration state of the surface of the image carrier. Is disclosed. However, the decrease in the image density is caused not only by the unevenness of the surface of the image carrier, but also by a change in capacitance due to deterioration of the material constituting the photoconductor, so that the failure prediction accuracy is still not sufficient.

  The present invention has been made in view of the above-described problems of the prior art, and provides an image forming apparatus capable of predicting the occurrence of image density change and resolution reduction during image formation and preventing the occurrence thereof. The purpose is to provide.

The said subject is solved by following (1)-(4) of this invention.
(1) “Electrophotographic photosensitive member, latent image forming means for forming an electrostatic latent image on the electrophotographic photosensitive member, developing means for visualizing the electrostatic latent image formed by the latent image forming means with toner, and the development An image having at least a transfer unit that transfers an image visualized by the unit to a transfer medium, and a cleaning unit that removes toner remaining on the surface of the electrophotographic photosensitive member by a contact member after the transfer process by the transfer unit. A forming device,
Furthermore, it has an electrophotographic photosensitive member temperature adjusting means capable of adjusting the temperature of the electrophotographic photosensitive member, and a torque measuring means for measuring a driving torque value of the electrophotographic photosensitive member,
The driving torque value of the electrophotographic photosensitive member when an image is formed by changing the temperature of the electrophotographic photosensitive member is measured, and the degree of deterioration and / or torque value of the electrophotographic photosensitive member calculated based on the change of the torque value is measured. An image forming apparatus having means for storing data ",
(2) The above-mentioned feature is characterized by comprising means for predicting an image density reduction amount based on the accumulated deterioration degree and / or torque value data and the previously acquired deterioration degree and / or torque value data. “Image forming apparatus according to item (1)”,
(3) “Furthermore, the electrophotographic photosensitive member surface is ground, and the surface of the electrophotographic photosensitive member is ground based on information from the means for predicting the image density reduction amount. The image forming apparatus according to (1) or (2),
(4) The above-mentioned items (1) to ((1), further comprising means for predicting and notifying the life of the electrophotographic photosensitive member based on information from the means for predicting the image density reduction amount. The image forming apparatus according to any one of items 3).

  As will be understood from the following detailed and specific description, according to the present invention, it is possible to predict the occurrence of a change in image density and a decrease in resolution during image formation and to prevent the occurrence of the occurrence. Equipment can be provided.

1 is a diagram illustrating an example of an image forming apparatus according to the present invention. It is a figure which shows an example of the torque measurement means which concerns on the image forming apparatus of this invention. It is a figure which shows an example of the relationship of a deterioration degree-time. It is a figure which shows the relationship between the deterioration degree of a photoconductor in a preliminary test, and the number of running. It is a figure which shows the relationship between the deterioration degree of a photoconductor in this test, and the number of running. It is an example of the form (flow) for implementing this invention. It is an example of the form (flow) for implementing this invention. It is an example of the form (flow) for implementing this invention. It is an example of the form (flow) for implementing this invention. It is an example of the form (flow) for implementing this invention.

(Mechanism of image density change / resolution reduction)
The electrophotographic photosensitive member has a surface electrical resistance that changes due to adhesion of foreign matters such as external additives and paper additives used for imparting fluidity to the toner, adsorption of discharge products, and the like after long-term use.

If the surface of the electrophotographic photosensitive member is reduced in electrical resistance due to adhesion of foreign matter, the maintenance of the latent image formed on the surface of the electrophotographic photosensitive member is hindered. cause.

  The discharge product is formed in the vicinity of a charger used to uniformly charge the surface of the electrophotographic photosensitive member. Specifically, ozone and nitrogen oxide are known (Journal of Imaging Science. 32). , 205-210), and these gases are highly oxidizable, and oxidize and deteriorate the surface of the electrophotographic photosensitive member. This reduces resistance due to changes in the components of the electrophotographic photosensitive member, increases hydrophilicity due to oxidation, and makes it easier for water to be adsorbed, and occurs between the adsorbed water and the adsorbed water and the photosensitive material and toner. Low resistance due to the product occurs, and maintenance of the electrostatic latent image is hindered as in the case of the adhesion of the foreign matter. For example, a decrease in the charging potential and an enlargement of the exposure potential decrease area (escape of charge in the adjacent unexposed area) occur. For example, in the case of negative / positive development, the line image is likely to be thickened or blurred.

  Conventional electrophotographic photoconductors have a short life cycle, so the effects of lowering the resistance of the electrophotographic photoconductor surface as described above are difficult to manifest, but the ultra-long life of today's electrophotographic photoconductors As a result of the development of image processing technology, the life cycle of electrophotographic photoconductors has become very long, which has created a situation where image defects such as image density changes and resolution reductions due to changes in surface resistance of electrophotographic photoconductors are likely to become obvious. Yes.

Furthermore, since the main means of the ultra-long lifetime technology is to improve the wear durability of the electrophotographic photosensitive member, the deposits and surface deterioration components are likely to remain and accumulate over a long period of time, resulting in a decrease in surface resistance. It promotes the manifestation of image defects.

  As a result of the present inventors diligently considering the occurrence mechanism of the image density change and resolution change, as a method for predicting the occurrence of image defects, a latent image having a predetermined pattern is formed on the surface of the electrophotographic photosensitive member, and developed with toner. The electrophotographic photosensitive member drive torque amount when scraping it with a cleaning blade changes depending on the temperature of the electrophotographic photosensitive member. It was found that the degree could be calculated quantitatively.

That is, when the surface resistance of the electrophotographic photosensitive member changes, the formed electrostatic latent image cannot be maintained, the amount of toner adhering to the surface of the photosensitive member changes, and the electron when the adhering toner is scraped off by the cleaning blade is changed. The driving torque of the photoconductor changes. Since the deteriorated electrophotographic photosensitive member is more susceptible to changes in surface resistance due to temperature changes, the degree of deterioration of the electrophotographic photosensitive member can be known.
It should be noted that measurement at a temperature equal to or higher than the glass transition temperature of the photoconductor / cleaning blade has a large variation in detection torque, and therefore, measurement is preferably performed below the glass transition temperature of the photoconductor surface layer / cleaning blade. Since the glass transition temperature on the surface of the photoreceptor is generally 90 ° C. or higher, it is preferably measured at 40 to 80 ° C.

  Specifically, by measuring the driving torque of the electrophotographic photosensitive member when an image is formed under two or more conditions where the temperature of the electrophotographic photosensitive member is different, a change in the toner adhesion amount due to a temperature change is estimated, When the change in the toner adhesion amount is large (the toner adhesion amount decreases), it can be easily determined that the degree of deterioration of the electrophotographic photosensitive member is large and the image flow is likely to occur.

The method for calculating the degree of deterioration of the electrophotographic photosensitive member will be exemplified below, but the present invention is not limited to this method.
For example, the surface temperature of the electrophotographic photosensitive member is arbitrarily changed, the photosensitive member temperature dependency of the estimated toner adhesion amount is measured, and the electrophotographic photosensitive member deterioration degree (η) is calculated by the following equation (1) based on the measurement result. And a method for calculating.

（ここで、Ｔ_１およびＴ_２はそれぞれ電子写真感光体ドラム温度（℃）を示し、Ｔ２＞Ｔ１の関係を有する。
｜Ｔｑｈ−Ｔｑｗ｜Ｔ_１、｜Ｔｑｈ−Ｔｑｗ｜Ｔ_２は、それぞれ、温度Ｔ_１での画像形成前後の駆動トルク差、温度Ｔ_２での駆動トルク差であり、前記ＴｑｈおよびＴｑｗはそれぞれ所定画像パターン入力時、および画像パターン未入力時の駆動トルク（ｋｇ・ｃｍ）を示す。）

(Here, T ₁ and T ₂ indicate the electrophotographic photosensitive drum temperature (° C.), respectively, and have a relationship of T2> T1.
| Tqh−Tqw | T ₁ and | Tqh−Tqw | T ₂ are a driving torque difference before and after image formation at temperature T ₁ and a driving torque difference at temperature T ₂ , respectively. Tqh and Tqw are respectively predetermined. The driving torque (kg · cm) when the image pattern is input and when the image pattern is not input is shown. )

If no image density abnormality occurs, for example, in the initial state of use of the electrophotographic photosensitive member, | Tqh−Tqw | (toner input index) does not change even if the temperature is changed. Become.
However, when the surface electrical resistance of the electrophotographic photosensitive member is reduced due to use, and the image density is reduced, the amount of toner to be developed decreases as the temperature rises.

の関係となり、式（１）の分子は０以上の数値をとるようになる。式（１）に示される電子写真感光体劣化度を逐次収集することで、図３に示すような劣化度―時間関係図が得られ、この劣化度―時間関係図を用いることで図３に示すようにシステム毎に予め設定された閾値に到達する時期に関する予測をすることが可能となる。

Therefore, the numerator of the formula (1) takes a numerical value of 0 or more. By sequentially collecting the degree of deterioration of the electrophotographic photosensitive member represented by the equation (1), a deterioration degree-time relationship diagram as shown in FIG. 3 is obtained. By using this deterioration degree-time relationship diagram, FIG. As shown, it is possible to make a prediction regarding the time at which the threshold value preset for each system is reached.

  Based on this prediction, if necessary, the surface of the electrophotographic photosensitive member is polished with a polishing member or the like before the predicted failure time, thereby removing deposits attached to the surface of the electrophotographic photosensitive member or oxidizing and deteriorating the outermost surface portion. That is, by removing the low resistance component, it is possible to prevent the occurrence of an image defect without confirming the occurrence of the image defect.

  Furthermore, based on this prediction, the failure time of the electrophotographic photosensitive member is predicted, and an alert is issued to the user in advance, so that the electrophotographic photosensitive member can be replaced without confirming the occurrence of the image defect. Occurrence can be prevented.

Next, the image forming apparatus of the present invention will be described.
FIG. 1 shows an example of an image forming apparatus of the present invention. The present invention is an image forming apparatus centering on the electrophotographic photosensitive member (101). The electrophotographic photosensitive member (101) is charged by the charging means (102), and an electrostatic latent image is formed by the exposure means (103). Further, a toner image is formed on the electrostatic latent image by developing means (104) that develops toner, and the toner image is transferred to paper or another medium by transfer means (105). Thereafter, the toner remaining on the surface of the electrophotographic photosensitive member is cleaned by the rubbing member (106). In addition, a photoreceptor heater (not shown) for heating the electrophotographic photoreceptor of the present invention to an arbitrary temperature within a temperature range of 40 ° C. to 80 ° C. is provided inside or outside the photoreceptor drum, A temperature sensor (108) for detecting the temperature of the photoconductor is provided.
Further, a polishing means (107) for polishing the surface of the electrophotographic photosensitive member when the surface of the electrophotographic photosensitive member changes to the extent corresponding to the occurrence of an image defect may be mounted.

FIG. 2 shows an example of an apparatus for driving an electrophotographic photosensitive member and detecting torque according to the present invention.
An electrophotographic photosensitive member end member (111) is connected to the end of the electrophotographic photosensitive member (101) and is in contact with the electrophotographic photosensitive member driving member (112). Generally, the electrophotographic photoreceptor end member (111) and the photoreceptor drive member (112) are gear-shaped. This drive member is connected to the electrophotographic photosensitive member torque measuring device (113) and measures the electrophotographic photosensitive member torque. Thereafter, the photosensitive member driving member is connected to driving means (114) capable of controlling the linear velocity via a torque measuring device.

The torque measuring device measures the torque applied when the electrophotographic photosensitive drum is rotated, and the control unit calculates the degree of electrophotographic photosensitive member deterioration from the data, and sequentially accumulates it in the accumulating unit.
These apparatuses are examples, and include at least an electrophotographic photosensitive member, a driving device for the electrophotographic photosensitive member, and a member in contact therewith, and measure the driving device for the electrophotographic photosensitive member and the torque of the electrophotographic photosensitive member. What is necessary is just to have a torque measurement means.

  As the rotational torque measuring device, a general torque measuring device can be used. Examples of the measurement method include a deflection meter method, a strain gauge method, and a magnetic phase difference method.

The control unit accumulates the driving torque data measured by the torque measuring device in the accumulation unit in the image forming apparatus as the electrophotographic photosensitive member deterioration degree information using the equation (1), and generates an image defect based on the accumulated data. In order to prevent it, the surface polishing means (107) of the electrophotographic photosensitive member is actuated or the failure time is notified to the user by the notification means.
In addition, by reporting the degree of deterioration information as maintenance information to an external control department or control organization using a communication means such as a telephone line, even if the actual user is unaware of the notification, the control department can respond. It becomes.

Next, an example of the electrophotographic photosensitive member deterioration degree data calculated based on the electrophotographic photosensitive member driving torque measured by the actual image forming apparatus will be shown.
A driving torque measuring device was installed on the electrophotographic photosensitive member, and Imagio MP C2200 manufactured by Ricoh Co., Ltd. was modified so that the temperature of the electrophotographic photosensitive drum could be controlled.
Further, as described above, since image defects are likely to occur in a long-life photoreceptor, an electrophotographic photoreceptor having a surface protective layer described in Japanese Patent No. 3734735 as an electrophotographic photoreceptor excellent in wear durability. Prepared.

As a method for measuring the degree of electrophotographic photosensitive member deterioration, the electrophotographic photosensitive drum temperature is set to 45 ° C. (T ₁ ) and 70 ° C. (T ₂ ), and a 2 by 2 latent image is formed on the surface of the electrophotographic photosensitive member for one turn at the temperature. Then, the degree of deterioration of the electrophotographic photosensitive member was measured.
At this time, the influence of the transfer belt was eliminated by separating the intermediate transfer belt from the photosensitive member.

This measurement was performed every 5 k of paper running, and first, 100 k running was performed as a preliminary test. FIG. 4 shows the relationship between the degree of deterioration of the electrophotographic photosensitive member obtained at this time and the number of running sheets.
In this image forming apparatus, it was found that the degree of deterioration of the electrophotographic photosensitive member tends to gradually increase with running, and has a tendency to increase linearly after 40 k running.
In addition, in the output image after 75k, it was visible that the image density and resolution were reduced compared to the initial stage. From this, it is possible to present the degree of deterioration (0.78) at the 75k time point as the threshold value of the degree of deterioration of the electrophotographic photosensitive member that causes a visible image density reduction or resolution reduction.

  Next, a new electrophotographic photosensitive member of the same type was prepared, and as a final test, paper formation running and evaluation were performed up to 50 k while changing the formed image and use temperature. FIG. 5 shows the relationship between the deterioration degree of the electrophotographic photosensitive member obtained at this time and the number of running sheets.

At the end of 50k running, image defects such as image density change or resolution reduction were not visible, and when the electrophotographic photoreceptor deterioration degree was about 0.5, no image defects occurred, and the results of the preliminary test were reproduced.
Further, it can be predicted that the degree of degradation of 0.78 presented as the image defect visual recognition threshold in the preliminary test reaches about 67.4k by extrapolating the result of FIG.
After that, as a result of continuous paper running, it was shown that image density reduction and resolution reduction that occurred at the end of 68k occurred, and the failure time could be predicted by the degree of deterioration of the present invention.

The image defect occurrence threshold of the degree of deterioration of the electrophotographic photosensitive member in the present invention varies depending on the electrophotographic photosensitive member to be applied, the system configuration, and the like, and needs to be newly set in image forming apparatuses having different configurations. The forming apparatus does not change depending on the use conditions and environment.

Next, the form (flow) for implementing this invention is demonstrated.
FIG. 6 shows an example of an embodiment of the present invention. (Embodiment 1)
The use of the image forming apparatus is started, and “S1: Electrophotographic photosensitive member driving torque (Tqw) when no image is input at electrophotographic photosensitive drum temperature 1 (T ₁ )” and “S2: Input of a predetermined image” Electrophotographic photosensitive member driving torque (Tqh) ”is measured.
Next, the temperature of the electrophotographic photosensitive member is changed so that the temperature of the electrophotographic photosensitive drum becomes 2 (T ₂ ), and “S3: Electrophotographic photosensitive member driving torque when no image is input (S3 and S2)” Tqw) ”and“ S4: electrophotographic photosensitive member driving torque (Tqh) when inputting a predetermined image ”are measured.
Based on the measurement results obtained in S1 to S4, using the above formula (1), "S5: Calculate the degree of electrophotographic photoreceptor deterioration", "S6: Accumulate the information", and return to S1. Repeatedly.

FIG. 7 shows another example of the embodiment of the present invention. (Embodiment 2)
After the start of use of the image forming apparatus, the processes of S1 to S6 are performed in the same manner as in the first embodiment, and “S7: Image defect occurrence time prediction” is performed based on the accumulated information of S6. Thereafter, the flow returns to S1 and this flow is repeatedly performed.
The predicted value of the image defect occurrence time is obtained from the intersection with a predetermined threshold by extending the regression line of FIG.

FIG. 8 shows another example of the embodiment of the present invention. (Embodiment 3)
After the use of the image forming apparatus is started, the processes of S1 to S7 are performed in the same manner as in the second embodiment to predict the image defect occurrence time (failure life).
Next, “S8: Whether or not the difference between the degree of deterioration at that time point and the image defect occurrence threshold of the degree of deterioration is the remaining life ε, it is smaller than the recovery required remaining life a that is set in advance. Judgment ”. If the determination is small (Yes), “S9: Surface polishing of electrophotographic photosensitive member” is performed to remove the low resistance component and refresh the electrophotographic photosensitive member. If the determination is large (No), the process returns to S1 and this flow is repeated.

FIG. 9 shows another example of the embodiment of the present invention. (Embodiment 4)
After starting the use of the image forming apparatus, the processes of S1 to S7 are performed in the same manner as in the third embodiment to predict the image defect occurrence time (failure life). Next, “S8: When the difference between the usage amount and the failure life at that time point is the remaining life ε, it is determined whether or not it is smaller than the preset notification remaining life b”. If the determination is small (Yes), “S9: Notification of remaining life of electrophotographic photosensitive member” is executed to prompt the user to replace the electrophotographic photosensitive member (END). If the determination is large (No), the process returns to S1 and this flow is repeated.

FIG. 10 shows another example of the embodiment of the present invention. (Embodiment 5)
After starting the use of the image forming apparatus, the processes of S1 to S7 are performed in the same manner as in the third embodiment, and the surface of the electrophotographic photosensitive member shown in S9 is polished when an image defect occurs. Immediately after this, the processes of S1 to S7 are performed again. When ε is a or less, “S9: Notification of remaining life of electrophotographic photosensitive member” is performed as in the fourth embodiment, and the electrophotographic photosensitive member is notified to the user. Encourage exchange (end). If ε is greater than or equal to a, the process returns to S1 and this flow is repeated.

Although the present invention has been described with the embodiments shown in the drawings, the present invention is not limited to the embodiments shown in the drawings, and those skilled in the art have conceived other embodiments, additions, modifications, deletions, and the like. It can be changed within the range that can be performed, and any embodiment is included in the scope of the present invention as long as the operation and effect of the present invention are exhibited.
Further, examples of an image forming apparatus using an electrophotographic system to which the present invention can be applied include a copying machine, a facsimile, a printer, and a digital multifunction machine including these. You may mount as a process cartridge which is one form of the structure of these image forming apparatuses.
The present invention can also be applied to a tandem full-color image forming apparatus. In this case, since a plurality of photoconductors are used, it is necessary to provide the above-described electrophotographic photoconductor drive torque detecting means and a series of devices provided as necessary, independently for each photoconductor. The mechanism is as described above, and it may be provided according to the number of photoconductors used.

As described above, the applicable range of the present invention is almost all in an image forming apparatus established by using an electrophotographic photosensitive member to which a known electrophotographic method is applied so far. The development method including transfer, the transfer method, and the like can be applied to any known method.

DESCRIPTION OF SYMBOLS 101 Electrophotographic photoreceptor 102 Charging means 103 Exposure means 104 Developing means 105 Transfer means 106 Sliding member 107 Polishing means 108 Temperature sensor 111 Electrophotographic photoreceptor end member 112 Electrophotographic photoreceptor driving member 113 Electrophotographic photoreceptor torque measuring device 114 Driving means

Japanese Patent No. 4387869 JP 2003-057855 A JP 2003-122222 A JP 2004-029059 A JP 2007-233049 A JP 2005-17874 A Japanese Patent No. 4672275

Claims (4)

An electrophotographic photosensitive member, a latent image forming means for forming an electrostatic latent image on the electrophotographic photosensitive member, a developing means for visualizing the electrostatic latent image formed by the latent image forming means with toner, and visualized by the developing means The image forming apparatus includes at least a transfer unit that transfers the transferred image to a transfer medium, and a cleaning unit that removes toner remaining on the surface of the electrophotographic photosensitive member by a contact member after the transfer process by the transfer unit. And
Furthermore, it has an electrophotographic photosensitive member temperature adjusting means capable of adjusting the temperature of the electrophotographic photosensitive member, and a torque measuring means for measuring a driving torque value of the electrophotographic photosensitive member,
The driving torque value of the electrophotographic photosensitive member when an image is formed by changing the temperature of the electrophotographic photosensitive member is measured, and the degree of deterioration and / or torque value of the electrophotographic photosensitive member calculated based on the change of the torque value is measured. An image forming apparatus having means for storing data.   2. The apparatus according to claim 1, further comprising means for predicting an image density reduction amount based on the accumulated deterioration degree and / or torque value data and the previously acquired deterioration degree and / or torque value data. Image forming apparatus. The electrophotographic photosensitive member surface is further polished, and the surface of the electrophotographic photosensitive member is polished based on information from the means for predicting the image density reduction amount. The image forming apparatus according to 2. 4. The image forming apparatus according to claim 1, further comprising means for predicting and notifying the life of the electrophotographic photosensitive member based on information from the means for predicting the image density reduction amount. apparatus.

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