JP2631374B2 - Image forming device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a process for forming a visible image on a surface of a latent image carrier by a plurality of process means, transferring the visible image to a transfer material, and supporting the latent image after transfer. An image forming apparatus for cleaning a body surface, wherein an image forming unit including at least one process means and a latent image carrier are detachably attached to an image forming apparatus main body, and a life of the image forming unit is detected. The present invention relates to an image forming apparatus provided with unit life detecting means and image carrier life detecting means for detecting the life of a latent image carrier.

2. Description of the Related Art An image forming apparatus of the above type configured as an electronic copying machine, a printer, a facsimile or the like has been conventionally known (for example, see Japanese Patent Application Laid-Open No. 61-118770). In this type of image forming apparatus, for example, at least one of process means such as a charging device, an exposure device, a developing device, a transfer device, a cleaning device, or a static elimination device forms an image forming unit separate from the latent image carrier, The unit and the latent image carrier are detachable from the image forming apparatus main body. Therefore, when the life of the image forming unit or the life of the latent image carrier has expired, each of them can be replaced with a new one.

In addition to the at least one process means, a latent image carrier is also integrally incorporated to form an image forming unit, and the unit is detachably mounted on the image forming apparatus main body to form the image forming unit. Similarly, an image forming apparatus that replaces the entire image forming unit when one of the latent image carriers constituting the unit has reached the end of its life is also known, but this configuration imposes an unnecessary economic burden on the user. There is fear. That is, with the recent development of technology, the life of a latent image carrier made of, for example, a photoconductor tends to be longer than the life of process means such as a developing device and a cleaning device. When the carrier is configured and used as an image forming unit, process means such as a developing device or a cleaning device may be used even though the latent image carrier has not reached the end of its life and can be used for a sufficiently long time. At the end of the life, the latent image carrier must be discarded, resulting in an economic loss. In that regard, in an image forming apparatus of the type described at the beginning, in which the image forming unit is configured as a separate unit from the latent image carrier, the image forming unit can be replaced separately from the latent image carrier,
The service life of the latent image carrier can be prolonged, and the above-mentioned problem concerning economic efficiency does not occur.

The fact that the latent image carrier and the image forming unit can be separately replaced as described above is very preferable in terms of economy. However, replacing both separately means that the number of replacements increases accordingly, which may force the operator to perform the replacement many times.

Then, after sequentially using the image forming unit while replacing it with a new one a predetermined number of times, when the last image forming unit has reached the end of its life, the latent image carrier is regarded as having reached the end of its life, It is also conceivable to replace both the latent image carrier with a new one. This makes it possible to reduce the total number of replacements as compared with the case where the image forming unit and the latent image carrier are completely and independently replaced. However, the time until the image forming unit reaches the end of its life varies greatly depending on the ratio of the image portion when an image is formed using the image forming unit.
When the life of the latent image carrier is determined in relation to the number of replacements of the image forming unit as described above, the life of the latent image carrier that has not actually reached the life and therefore can be used for a sufficiently long time is replaced. The situation that must be done occurs, and the economic efficiency decreases. The latent image carrier and the image forming unit are detachably mounted on the main body of the image forming apparatus so that they can be exchanged separately, thereby losing the advantage of increasing the economic efficiency.

SUMMARY OF THE INVENTION The present invention has been made based on the above recognition, and has been made in consideration of the above-described problems, and has the object of eliminating the problems of economical efficiency and of reducing the number of replacements between the latent image carrier and the image forming unit as much as possible. It is intended to provide a device.

In order to achieve the above object, the present invention provides an image forming apparatus of the type described at the beginning, wherein the image carrier life detecting means detects the number of image formed sheets, the number of rotations of the latent image carrier, or the latent image carrier. Means for detecting the life of the latent image carrier by detecting deterioration of the image forming means, display means for displaying that the image forming unit should be replaced when the life of the image forming unit is detected, and detection of the life of the latent image carrier. Means for prohibiting an indication that the latent image carrier should be replaced when the life of the image forming unit has not been detected, and An image forming apparatus comprising: a display unit for displaying that both the image forming unit and the latent image carrier should be replaced when the image forming unit is detected.

According to a second aspect of the present invention, in the image forming apparatus of the type described above, when the life of the image forming unit is detected within a predetermined number of image forming times after the life of the latent image carrier is detected, Display means for displaying that both the unit and the latent image carrier should be replaced; and when the life of the image forming unit is not detected within the range, the latent image carrier is replaced after the predetermined number of image formations. Display means for displaying what should be done, and display means for displaying that the image forming unit should be replaced when the life of the image forming unit is detected outside the above range. An image forming apparatus is proposed.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In this embodiment, the present invention is applied to an electronic copying machine as an example of an image forming apparatus. First, the overall configuration and operation will be clarified with reference to FIG.

In the present example, a contact glass 2 is supported on the upper part of the image forming apparatus main body which is the copying machine main body 1 so as to be able to reciprocate in a horizontal direction, and an original (not shown) is placed thereon.
Being held down by In the state shown in FIG. 1, a latent image carrier configured as a drum-shaped photoconductor 4 is rotatably supported inside the copying machine main body 1.

During the copying operation, the contact glass 2 moves in the horizontal direction, and at this time, the original on the contact glass 2 is illuminated by the light source 5. The reflected light passes through the convergent light transmitting body 6 and reaches the surface of the photoreceptor 4 which is rotated clockwise by a driving device (not shown), and forms an original image on the surface of the photoreceptor. Since the surface of the photoconductor 4 is previously charged to a predetermined polarity by a charging device including the charging charger 7, an electrostatic latent image is formed on the photoconductor by the above-described exposure.

The latent image is visualized by toner as it passes through the developing device 8. The illustrated developing device 8 includes a developing case 10 containing toner 9, a developing roller 11 that carries the toner on the peripheral surface and transports the toner 9 to the photoreceptor surface, and a toner supply roller 50 that supplies the toner 9 to the developing roller 11. And
The toner on the developing roller 11 is electrostatically transferred to the photoconductor, and the latent image is visualized. Developing roller 11 and toner supply roller
Reference numeral 50 is rotatably supported by the developing case 10 and is rotationally driven by a driving device (not shown). Further, a two-component developer containing a carrier other than the toner 9 may be housed in the developing case 10 and used.

On the other hand, a transfer material composed of copy paper 14 is fed from a paper feed cassette 12 detachably mounted on the copying machine main body 1 and fed to the surface of the photoconductor 4 at a predetermined timing by a pair of registration rollers 13. Then, the visible image on the photoreceptor 4 is transferred to copy paper by a transfer device including the transfer charger 15. After the transfer process, the copy paper is separated from the photoreceptor 4 and then passes through a fixing device 16 where a visible image is fixed,
The sheet is discharged to the sheet discharge tray 17.

The surface of the photoreceptor after the transfer of the visible image is subjected to a charge removing operation by a charge removing device (not shown), and the toner remaining on the surface contacts the cleaning member of the cleaning device 18, in the illustrated example, the photosensitive member surface. Cleaning blade 19
And the surface of the photoreceptor is cleaned. The collected toner is stored in the toner container 20a of the cleaning case 20.
To be housed.

The copier body 1 is separated into two parts, an upper structure 51 and a lower structure 52. The upper structure 51 is pivotally connected to the lower structure 52 via a pivot pin 53 so as to be able to rotate in the direction of arrow A. Have been. During a normal copying operation, the upper structure 51 is connected to the lower structure 52 as shown in FIG.
Is set on top of

In the present embodiment, the developing case 10 and the cleaning case 20 are integrally formed, so that the developing device 8 and the cleaning device
Imaging unit with 18 process means integrated
Make up 34. Further, in the illustrated example, the charging charger 7 is also provided in the cleaning case 20, so that the process means including the charging charger 7 also constitutes a part of the image forming unit 34. Cleaning case 20 and developing case 10
Can be pivotally connected to each other so that the two devices 8, 18 can be integrally assembled. As will be described later, the image forming unit includes at least one process means.

As described above, the illustrated image forming apparatus forms a visible image on the surface of the latent image carrier made up of the photoreceptor 4 by a plurality of process means and transfers the visible image to a transfer material made of copy paper. In addition, the surface of the latent image carrier after the transfer is cleaned.

As can be seen from FIGS. 2 and 3 showing the state in which the upper structure 51 is rotated, the photosensitive member 4 has two photosensitive member shafts 54 projecting from the front and rear ends thereof fixed to the bottom plate of the lower structure 52. The photoreceptor support members 55 are supported rotatably and detachably by bearings 56 of the provided photoreceptor support members 55, respectively. The “back and forth” here means the first
The front side in the direction perpendicular to the paper surface of FIGS. 3 to 3 is referred to as “front”, and the back side is referred to as “rear”. FIG. 1 shows only the support member 55 that supports the rear, that is, the back, photoconductor shaft 54,
FIGS. 2 and 3 show only the photosensitive member shaft 54 on the front side, that is, the front side, and a supporting member 55 for supporting the same. The image forming unit 34 is detachably supported by the upper structure 51. As described above, both the image forming unit 34 and the photoconductor 4 are detachably mounted on the copying machine main body 1.
The photoconductor 4 can be assembled as shown in FIG. 1 or separated from each other as shown in FIG. The image forming unit including at least one process means and the latent image carrier are detachably mounted on the image forming apparatus main body.

The other elements described above are also supported by the upper structure 51 and the lower structure 52, respectively, and it is clear which of these structures is supported by comparing FIGS. 1 and 2.

The copying operation is performed as described above. When such an operation is repeated, the toner 9 in the developing case 10 of the developing device 8 is
Is consumed. And when this falls below the predetermined amount,
The density of the visible image formed on the photoconductor 4 decreases, and the image quality deteriorates. This is the life of the developing device 8. Usually, the time from when the image quality is deteriorated due to a shortage of toner amount or shortly before that until the toner in the developing case 10 becomes empty is defined as the life of the developing device. It has established. On the other hand, the toner is sequentially accumulated in the toner storage section of the cleaning case 20, and when the toner is full, the toner cannot be stored. Therefore, in this case as well, the life of the cleaning device 18 is defined as the time when the inside of the cleaning case 20 is full of toner or a time just before that.

The photoreceptor 4 also deteriorates with time, and the quality of the visible image formed on the surface of the photoreceptor 4 starts to deteriorate. This is the life of the photoreceptor. In this case, the life of the photoreceptor is usually defined as the time when noticeable image quality degradation starts or a time immediately after the time immediately before the time.

If it is determined that the image forming unit 34, that is, the cleaning device 18 or the developing device 8 is suitable for the life, the image forming unit 34
It is necessary to replace 34 with a new one, and similarly when the photoconductor 4 reaches the end of its life, replace it with a new one. In such a case, the upper structure 51 is rotated in the direction of arrow A as shown in FIG. At this time, the imaging unit 34
Is lifted together with the upper structure 51 while being supported by the upper structure 51, while the photoconductor 4 is left on the lower structure side while being supported by the support member 55. Thus, the image forming unit 34 and the photoconductor 4 that have been assembled are separated from each other. Next, the image forming unit 34 is detached from the upper structure 51, pulled out in the direction of arrow B, for example, and a new image forming unit is mounted on the upper structure 51. Similarly, when the upper structure 51 is lifted, the upper part of the photoconductor 4 is opened, so that the photoconductor 4 can be removed from the support member 55 and can be replaced with a new one. After the replacement work, the upper structure 51 is returned to the state shown in FIG. 1, and the copying operation can be resumed. The replacement operation can be performed not only when the image forming unit has reached the end of its life but also when the image forming unit is replaced with a developing device containing a toner of another color.

The developing device 8 and the cleaning device 18 are pivotally connected to each other as described above, and when the image forming unit 34 is lifted as shown in FIG.
When the unit 34 is configured to be close to each other and the lower opening thereof is closed, the inconvenience of toner spilling when the unit 34 is attached to and detached from the upper structure 51 can be advantageously removed.

FIG. 3 shows an embodiment in which the image forming unit 34 and the photoreceptor 4 are lifted together by the rotation of the upper structure 51 so that they can be replaced together. This will be described later.

As described above, since only the image forming unit 34 can be replaced while the photoconductor 4 is left in the copying machine main body 1, even if the life of the photoconductor 4 is longer than the life of the developing device 8 and the cleaning device 18, It is possible to eliminate waste such as discarding the still usable photoconductor 4 together with the image forming unit 34, thereby preventing the occurrence of economical loss. However, if only the photoconductor 4 and the image forming unit 34 can be replaced separately as described above, the number of replacements between the image forming unit 34 and the photoconductor 4 increases as described above. Therefore, the operator has to perform complicated work many times.

Therefore, in the present embodiment, the operator is required to always replace the image forming unit 34 when replacing the photosensitive member 4, so that it is possible to eliminate waste in work such as replacing only the photosensitive member 4. ing. That is, the photoconductor 4
Is replaced with the replacement time of the image forming unit 34 so that both are replaced, and the number of replacement operations is reduced as much as possible. First, the principle will be clarified.

First, in the image forming apparatus including the copying machine shown in FIG. 1, the life of one of the developing device 8 and the cleaning device 18 has expired, that is, the unit life detection for detecting the life of the image forming unit 34. Means and an image carrier life detecting means for detecting the life of the latent image carrier composed of the photoconductor. Although specific examples of these detecting means will be described later in detail, the image carrier life detecting means of the present example detects the number of images formed, detects the rotation speed of the latent image carrier composed of the photoconductor 4, or detects the latent image carrier. It comprises means for detecting the life of the latent image carrier by detecting deterioration. If such an image carrier life detecting means is used, the life of the latent image carrier composed of the photoconductor 4 can be correctly detected, and the photoconductor 4 has not yet reached the actual life and has been sufficiently long. In a state where the photosensitive member 4 can be used for a long time, it is possible to prevent such a problem that the photosensitive member 4 is replaced. In the following description, the image carrier life detecting means may be referred to as a photoconductor life detecting means in accordance with the configuration of an actual example.

FIG. 4 (a) is a graph in which the horizontal axis indicates the usage time of the photoconductor 4, and the vertical axis indicates the image quality of the visible image which changes with the aging of the photoconductor 4. As can be seen from this, the surface of the photoreceptor 4 gradually deteriorates from the start of use, and the quality of the visible image deteriorates. In this example, it is assumed that the photosensitive member life detecting means detects that the photosensitive member 4 has reached the end of life at the time indicated by X1.

On the other hand, FIG. 4 (b) is a graph in which the horizontal axis represents the usage time of the imaging unit 34 and the vertical axis represents the image quality of the visible image which changes with the lapse of the usage time of the unit.
Indicates the image quality status of the first image forming unit, 2Y indicates the image quality status of the next changed image forming unit, and similarly, 3Y and 4Y indicate the image quality of the image forming unit replaced and used one after another. Each situation is shown. That is, when the first image forming unit 34 (1Y) is started to be used at the time of 1Y1, the image quality of the visible image starts to decrease at the time of 1Y2, for example, as the toner image of the developing device 8 decreases, and At this point, the life of the image forming unit 34 is detected by the unit life detecting means. At this time, a message to replace the unit is displayed.
Replace with 34 (2Y). Then, the image quality becomes high quality again, but the image quality starts to deteriorate again at 2Y2, and the life of the imaging unit is detected at 2Y3, and this unit is replaced. The imaging unit 34 (3Y, 4Y) follows a similar process.
Every time the life is detected, the unit is replaced.

As can be seen by comparing FIGS. 4A and 4B, the life of the photoreceptor 4, that is, the time from the start of use of the photoconductor 4 to the point of time X1 is determined by the life detection 1Y3, 2Y
It is longer than the time up to 3,3Y3,4Y3, and in the example of FIG. 4, the photoconductor 4 has a life almost four times as long as the image forming unit.
In this case, if the time X1 at which the photosensitive member 4 reaches the end of its life and the time at which the image forming unit reaches its end of life (for example, the point of time 4Y3) always match, the photosensitive member 4 is simultaneously replaced when the image forming unit is replaced. Since they can be exchanged, the efficiency of the work can be increased. However, as can be seen from the examples of FIGS. 4 (a) and 4 (b), the time points X1 and 4Y3 do not always coincide, but rather do not usually coincide. Since the time from the start of using each image forming unit 34 to the end of its life varies greatly depending on the use conditions of the copying machine, especially the ratio of the image portion to the background portion of the visible image,
This is because, even if it is attempted to configure the photoconductor 4 and the image forming unit 34 so that X1 and 4Y3 match, it can be said that it is impossible to always match these times. For this reason, conventionally, each time the life of each imaging unit is detected, the unit is replaced, and when the life of the photoconductor 4 is detected, only the photoconductor has to be replaced. The total number of replacements was increasing.

Also, as described above, after the image forming unit is used a predetermined number of times while sequentially replacing it with a new one, when the last image forming unit reaches the end of its life, the photoconductor has reached the end of its life. It can be considered that the image forming unit and the photoconductor are both replaced with new ones.However, if such a method is adopted, as described above, the time until the image forming unit reaches the end of its life is particularly reduced in the image area. Since the ratio greatly varies depending on the ratio, the photoconductor may need to be replaced even though the photoconductor is still in a usable state.

Therefore, in this embodiment, as described above, as the photoconductor life detecting means, as described above, without being related to the number of replacements of the image forming unit 34,
Uses a means to detect the life of the photoconductor by detecting the number of images formed. This solves the economical problem of replacing the photoconductor, even though it is still in a usable state. I do. Moreover, the photoconductor 4
If the life of the image forming unit used at that time is not detected, the display for replacing the photoconductor is prohibited, that is, the display is not performed, and the use of the copying machine is continued. . Then, only when the life of the image forming unit is detected, the display to replace both the photoconductor and the image forming unit is displayed for the first time, and both are replaced together. Explaining with reference to FIG. 4 (a), even if the life of the photoconductor is detected at the time of X1, there is no indication that the photoconductor should be replaced.
At this time, the life of the image forming unit indicated by 4Y is 4Y3
When the detection is made at the point of time, not only this unit but also the photoconductor 4 is displayed to be replaced. The operator exchanges both together according to this. As described above, if the replacement time of the photoconductor is matched with the replacement time of the image forming unit, the operator does not need to replace only the photoconductor 4 alone, and the work efficiency is improved.

However, with the configuration described above, there is a time indicated by ΔX in FIG. 4A from the detection of the life of the photoconductor 4 to the actual replacement thereof. For this reason, it is necessary to continue using the photoreceptor which has already reached the end of its life. However, the fourth
As can be seen from the figure, the life of the image forming unit is extended due to a decrease in the amount of toner and the like. Therefore, when the life is short, the image quality of a visible image is rapidly deteriorated. The deterioration of the image quality of the visible image with the passage of time is very gradual, and even if this is used for a considerably long time (for example, ΔX in FIG. 4) after the life of the photosensitive member is detected, the deterioration of the image quality relatively occurs. Hateful. Therefore, even if the photosensitive member 4 is replaced after a certain period of use after the detection of the service life of the photosensitive member 4, if the entire service life of one image forming unit is relatively short, there is little practical problem. Of course, the life detection of the photoconductor 4 and the life detection of the image forming unit may be performed at the same time. In this case, ΔX becomes zero. In addition, by setting the time X1 at which the life of the photoconductor 4 is detected to be earlier than the actual usage time of the photoconductor before the image quality starts to significantly deteriorate, the above-described inconvenience is more reliably prevented. it can.

Table 1 shows the above relationship in general.

Next, a specific example of the above-described configuration will be described.

In FIG. 5, when the image forming unit 34 reaches the end of its life,
A unit life detecting signal from the unit life detecting means 60 which detects this is input to a first display 61 arranged on a display panel of the copying machine main body, and is turned on to turn on the image forming unit.
The display indicates that 34 should be replaced. This life detecting means 60
Is also input to the AND circuit 62. At this time, the photoconductor 4 has not reached the end of its life. Therefore, the photoconductor life detection signal is input to the AND circuit 62 from the photoconductor life detecting means 63. If not, there is no AND output from the AND circuit 62, and the second display 64 indicating replacement of the photoconductor is not turned on. That is, only the first display is lit, indicating that only the image forming unit should be replaced. The operator accordingly replaces only the image forming unit 34 without replacing the photoconductor 4. The situation at this time corresponds to 1Y3, 2Y3 and 3Y3 in FIG. 4 (b).

Conversely, when the photoconductor 4 reaches the end of its life and the photoconductor life detection signal from the photoconductor life detection means 63 is input to the AND circuit 62, if the unit life detection signal is not output from the unit life detection means 60, the AND Since there is no AND output from the circuit 62, the second display 64 does not light up, and both the displays 61 and 64 eventually remain off. The state at this time corresponds to the state at the time of X1 in FIG. 4A, and the copying operation is continued as it is.

After the time of X1, that is, when the life of the image forming unit is detected in a state where the photoconductor life detection signal is output, a life detection signal is output from both of the detection means 60 and 63, and a signal from the AND circuit 62 is output. The AND output is input to the second display 64, and the output from the unit life detecting means 60 is input to the first display 61. Both the displays 61 and 64 are turned on, and both the photoconductor 4 and the image forming unit are replaced. It shows what to do. The operator exchanges both according to this. This is shown in FIG.
4Y3.

In the example of FIG. 5, the first display 61 constitutes an example of the display means for displaying that the unit should be replaced when the life of the image forming unit is detected, according to claim 1. Similarly, the AND circuit 62 constitutes an example of a unit for prohibiting the display indicating that the latent image carrier should be replaced when the life of the latent image carrier is detected and the life of the image forming unit is not detected. I do. Similarly, the first and second indicators 61, 6
4 and the AND circuit 62 indicate that both the image forming unit and the latent image carrier should be replaced when the life of the image forming unit is detected after the life of the latent image carrier is detected. This constitutes an example of the display means.

In the embodiment shown in FIG. 6, each detecting means 60, 63
When the life of the image forming unit 34 or the photoconductor 4 has not been detected yet, the output from each of the detecting means 60 and 63 is at the L level. The output from 63 is branched into two, and the branched outputs from the unit life detecting means 60 are input to first and second AND circuits 162 and 62, respectively. One output branched from the photoconductor life detecting means 63 is directly input to the second AND circuit 62, and the other output is input to the first AND circuit 162 via the inverting circuit 65.

When only the life of the imaging unit 34 is detected (at 1Y3, 2Y3, 3Y3 in FIG. 4B), the unit life detecting means 6
The output of 0 becomes H level, which is branched and input to each of the AND circuits 162 and 62. At this time, the photosensitive member life detecting means
The output of 63 remains at the L level, and one of the branches is directly inverted by the second AND circuit 62, and the other is inverted by the inverting circuit 65, and is input to the first AND circuit 162 at the H level. Therefore, only the output of the first AND circuit 162 becomes H level, whereby only the first display 61 is turned on, indicating that only the image forming unit 34 should be replaced.

When only the life of the photoconductor 4 is detected (FIG. 4A)
X1), the output from the photosensitive member life detecting means 63 is H
One of the two levels is directly input to the second AND circuit 62. The other is inverted by the inverting circuit 65 to have the L level, and is input to the first AND circuit 162. On the other hand,
The output from the unit life detecting means 60 is at L level,
Therefore, there is no output of H level from both AND circuits 62 and 162, and both indicators 61 and 64 maintain the OFF state.

After the time point X1, that is, when the life of the photoconductor 4 is detected and the output of the detection means 63 becomes H level, and the life of the image forming unit 34 is also detected (4Y3 in FIG. 4B). At this time, the outputs from both the detecting means 60 and 63 both become H level. For this reason, the H level output and the L level output from each detecting means are input to the first AND circuit 162, and the first display
61 maintains the light-off state. On the other hand, the H level output from each of the detecting means 60 and 63 is input to the second AND circuit, and the second display 64 is turned on. The second display 64 indicates that both the photoconductor 4 and the image forming unit 34 should be exchanged, and the operator exchanges both according to the instruction.

In the example of FIG. 6, when both the photosensitive member 4 and the image forming unit 34 are to be replaced, only the second display 64 for displaying the light is turned on, and the first indicating that only the image forming unit 34 is to be replaced is displayed.
Since the display 64 does not light up, the operator can immediately understand the meaning of the display simply by looking at the display panel. It can be said that the display mode is easy for the operator to understand.

In the configuration shown in FIG. 6, the first display 61, the first
The AND circuit 162 constitutes an example of a display means for displaying that the unit should be replaced when the life of the image forming unit is detected. Similarly, the first and second AND circuits 162 and 62 and the inversion circuit 65 Constitutes an example of means for prohibiting the display of the need to replace the latent image carrier when the life of the latent image carrier is detected and the life of the image forming unit is not detected. Furthermore, the second display 64, the first and second AND circuits 162 and 62, and the inverting circuit 65 mainly operate when the life of the image forming unit is detected after the life of the latent image carrier is detected. An example of display means for displaying that both the image forming unit and the latent image carrier should be replaced is configured.

By the way, in the embodiment shown in FIGS. 4 to 6, there is a time ΔX between the time when the life of the photoconductor 4 is detected and the time when the photoconductor 4 is actually replaced. Is as described earlier. However, this time ΔX may extend to a time corresponding to the entire life of one image forming unit at the maximum, and in such a case, it may be significantly deteriorated by the actual replacement time of the photoconductor, and It is also conceivable that the image quality of the image is significantly reduced.

Therefore, adopting an exchange method as shown in FIGS. 7 (a) and 7 (b) is advantageous because the time of ΔX can be reduced. That is, as shown in FIG. 7, when each image forming unit is used while being sequentially exchanged like 1Y, 2Y, 3Y..., And at the time of X1, the photosensitive member 4 reaches the life in the above-described embodiment,
At the time when each image forming unit reaches the end of its life, it is determined how much time is left before the end of the life of the photoconductor (until the time X1 comes). When it is determined that the photoconductor 4 reaches the end of its life X1 when the next imaging unit is used, the photoconductor 4 is used before the next imaging unit is used according to the remaining time in which the photoconductor can be used. Is to be replaced, or the photoconductor is to be replaced after using the next image forming unit. That is, as illustrated in FIG. 7A, the life of the image forming unit 34 indicated by 3Y is 3Y3
When the time Z1 from this point to the life time X1 of the photoreceptor is less than, for example, 1/2 or less of the total life time W of one image forming unit, the 3Y image forming unit When the life is detected (3Y3), not only the image forming unit but also the photoconductor 4 is replaced.

Conversely, as shown in FIG. 7B, for example, when the life of the image forming unit indicated by 3Y is detected at the time of 3Y3, when the time Z1 until the life of the photoconductor 4 is longer than, for example, W / 2 Is 3Y3
At this point, the photoconductor is not replaced, and only the image forming unit is replaced. Then, the life of the imaging unit indicated by 4Y is 4Y3
Is detected, the unit and the photoconductor 4 are both replaced.

In this way, the time ΔX shown in FIG. 4 can be suppressed to a half of the total lifetime of one imaging unit at the maximum.

FIGS. 8 (a) and 8 (b) are explanatory diagrams showing an example when embodying the above idea. X1 in this figure is the seventh
Similar to FIGS. 4A and 4B, this is the lifetime of the photoconductor in the embodiment shown in FIG. In this case, in this example, the photosensitive member life detecting means 63 shown in FIG. 5 or FIG.
At this point, the photosensitive member life detection signal is not output, and as can be seen from FIGS. 8 (a) and 8 (b), it is earlier than X1 by W / 2, which is half of the average life W of one imaging unit. At time point Z2, a photoconductor life detection signal is output from the detection means 63.
Other configurations are the same as the previous embodiment. That is,
As shown in FIG. 8 (a), when the photoconductor life detection signal is output at the time point Z2, if the life of the image forming unit indicated by 3Y in use at this time point is not detected, the photoconductor life is detected. No indication of replacement of the image unit is made. Then, only when the life of the image forming unit is detected at 3Y3, a display for replacing both the photosensitive member and the image forming unit is displayed.

In the case of FIG. 8B, when the photosensitive member life detection signal is output at the time point of Z2, the image forming unit indicated by 4Y has already been used, and in this case, the life of the image forming unit is 4Y.
When the detection is made at the point of time 3, an indication is given to replace both the photosensitive member 4 and the image forming unit.

In short, the output timing of the photoconductor life detection signal is advanced by W / 2 earlier than the life X1 of the photoconductor, and the photoconductor 4 is detected when the life of the imaging unit 34 is detected after the photoconductor life detection at this time. The display for replacing both the image forming unit 34 and the image forming unit 34 is made.

Specifically, the method of setting the timing of Z2 is as follows.For example, when the configuration of detecting the life of the photoconductor by counting the number of copies processed as described later is adopted as the photoconductor life detection means, copying up to X1 is performed. Assuming that the number m of processed images is 10,000, for example, and the average life W of one image forming unit is 3,000 in terms of the number of copies, W / 2 = 1500. When the number of copy processing sheets is counted, it becomes the time point of Z2, and at this time, a photoconductor life detection signal is output.

The idea shown in FIG. 8 can also be embodied in the same manner as in the above-described embodiment using the configuration shown in FIG. 5 or FIG.

In the embodiment shown in FIG. 8, the output timing of the photosensitive member life detection signal is advanced by 1/2 of the average life W of the image forming unit as compared with the embodiment of FIG. 7
This is a concrete example of the configuration shown in the figure, and this configuration can reduce ΔX shown in FIG. However,
In both embodiments, when the life of the photoconductor is detected (X1 or
After Z2), when the life of the image forming unit is detected next time, it is common that both the photoconductor and the image forming unit are displayed to be replaced. In both embodiments,
It goes without saying that there is no problem even if the time (X1, Z2) of the photoconductor life detection signal coincides with the time of generation of the unit life detection signal.

According to the embodiment shown in FIGS. 7 and 8, Δx shown in FIG. 4 can be shortened, and the inconvenience of using the photoreceptor having reached the end of its life for a long time can be prevented. However, when the image forming unit is configured so as to have a longer life, W / 2 itself in FIGS. 7 and 8 becomes longer. Therefore, even when the structure of this embodiment is adopted, the life is reached. ,
In some cases, a photoconductor having deteriorated quality must be used for a long period of time. What prevents such inconvenience is the second invention of the present application.

2A and 2B are explanatory views for explaining the principle of the embodiment. X1 indicates the life time of the photoconductor 4 as in FIGS. 8 (a) and 8 (b). In this embodiment, however, the life of the photoconductor is not detected at the time of X1, but is slightly longer. At the time point indicated by P, the life of the photoconductor is detected.
It is assumed that the number of times image formation is performed (the number of copies in this example) is N before the photosensitive member 4 reaches the end of life at the point X1 after the detection of the photosensitive member life at the point P. The number N is a predetermined number of times. Also, 1Y, 2Y... In FIGS. 9 (a) and 9 (b) indicate that the image forming units 34 are used while sequentially replacing them, and the total life time of each image forming unit as shown in FIG. It is shorter than the entire lifetime of the photoconductor 4.

As illustrated in FIG. 9 (a), the life of the photoconductor 4 is detected at the time point P, and after this time point, at a time point 3Y3 within a predetermined range of the number N of copies, If the life of the imaging unit 34 (3Y) that has been used is detected, then the imaging unit 34 (3Y) is used.
The display means indicates that (3Y) and the photoconductor 4 should be replaced at the same time. The operator replaces both the photoconductor 4 and the image forming unit 34 (3Y) in accordance with this. This is the first
Mode.

Next, as illustrated in FIG. 9 (b), after the life of the photoconductor is detected at the time point P, and within a predetermined number N, the image forming unit 34 (3Y) in use at that time. When the life of the photoconductor 4 is not detected, after the copying operation has been performed a predetermined number of times N, that is, at the time of X1, a display to replace only the photoconductor 4 is made by the display means. Accordingly, the operator does not replace the imaging unit 34 (3Y), and
Only exchange for a new one. This is the second mode.

When the life of the image forming unit 34 is detected at a point outside the range where the predetermined number of copies N is performed from the point P described above, that is, 1Y3, 2Y3 and FIG. 9 (b) in FIG. At the time of 1Y3, 2Y3, 3Y3 in the above), a display to replace only the image forming unit 34 used so far is made by the display means, and the operator follows the instruction and does not replace the photoconductor 4, and the image forming unit is replaced. Just replace. This is the third mode.

In the third mode described above, when only the image forming unit 34 has reached the end of its life, as in the previous embodiments, it is replaced alone. The first mode is a mode in which when the photosensitive member 4 reaches the end of its life or almost reaches its end, and the image forming unit reaches its end of its life, these units are simultaneously replaced. In the second mode, when the life of the image forming unit does not expire and only the photoconductor reaches the end of its life, the photoconductor is replaced alone. With the addition of the second mode, each image forming unit 34
Even when the total lifetime of the photoconductor is long, it is possible to prevent the inconvenience of continuously using the photoconductor whose life has expired for a long period of time. In this mode, even if the image forming unit 34 has not reached the end of its life, if the usage period of the photoconductor 4 reaches X1, the photoconductor 4 will be replaced. In addition, since the first mode is provided, the replacement time of the photoconductor 4 and the image carrying unit 34 is made coincident, and by replacing them at the same time, the number of replacements of the photoconductor 4 or the image forming unit can be reduced as compared with the related art. It is possible.

For example, it is assumed that the number of times that the copying machine forms an image (in this example, the number of copies) is 100,000 times from the start of using a new photoconductor 4 to the end of the life of X1 shown in FIG. Assuming that the total life time of the image forming unit is 30,000 times on average in terms of the number of copies (the actual number is not fixed,
N depends on the number of copies, for example, 5000 times. In this way, even if the life of each imaging unit 34 is as long as about 30,000 copies, the photosensitive member 4 can be changed from 100,000-5,000 = 95,000 copies to 100,000 copies. The photoconductor 4 is always replaced until it reaches the limit, and the use of the deteriorated photoconductor 4 can be continued, thereby preventing the inconvenience of significantly reducing the quality of the copied image.

The above-mentioned timing of X1 does not necessarily need to be coincident with the number of times the photosensitive member has been used (the number of copies) at which noticeable image quality degradation starts, and may be slightly more or at least better. As described above with reference to FIG. 4, the deterioration of the photoreceptor does not occur rapidly, and even if the setting of the timing of X1 fluctuates slightly, a serious inconvenience occurs in actually using the copying machine. Because there is nothing. In short, based on the number of times the photoconductor is used until noticeable image quality deterioration starts, a certain predetermined number of copies may be determined as the life number X1 of the photoconductor, which is shown in FIGS. 7 and 8. The same applies to the illustrated embodiment. The predetermined number N may be appropriately determined as the standard of X1 in consideration of the economical efficiency of using the photoconductor and the number of replacement operations. That is, if N is increased, the photosensitive member 4
May need to be replaced relatively early before it reaches the end of its service life, which may result in a slightly less economical situation. The number of replacement operations can be reduced. Conversely, if N is reduced, the opposite can be said.

FIGS. 10 and 11 show a more specific configuration example for implementing the configuration shown in FIGS. 9 (a) and 9 (b).

The configuration shown in FIG. 10 corresponds to the AND circuit 62 shown in FIG.
, A counter 200 is connected in parallel, the output from the photoconductor life detecting means 63 is also input to the counter 200, and the output is input to the second display 64. There is no difference from the configuration in the figure. That is, also in the case of FIG. 10, when the life of the image forming unit 34 (1Y, 2Y...) Is detected by the unit life detecting means 60, the unit life detection signal is transmitted to the first panel arranged on the display panel of the copying machine main body. display
This is input to 61, which lights to indicate that the imaging unit 34 should be replaced. The unit life detecting signal from the life detecting means 60 is also input to the AND circuit 62. At this time, the usage time (the number of copies) of the photoconductor 4 has not reached P, and thus the life of the photoconductor 4 has been shortened. Detection means
When the photoconductor life detection signal is not input from 63 to the AND circuit 62, there is no AND output from the AND circuit 62, and the second display 64 indicating replacement of the photoconductor is not turned on. That is, only the first display is turned on to notify the operator that only the image forming unit should be replaced. The situation at this time is 1Y3, 2Y3 in FIG. 9 (a).
Corresponds to 1Y3; 2Y3; 3Y3 in FIG. 9 (b), which is the third mode described above.

Next, the first mode is as follows. That is, the photoconductor 4
When the use time reaches P shown in FIG. 9 (a), a photosensitive member life detecting signal is output from the photosensitive member life detecting means 63, and this is the AND circuit 62 and the counter 200.
Is also entered. As a result, the counter 200 starts operating, and counts while adding this each time the copying machine performs a copying operation once. When the counted number reaches a predetermined number N, the use period of the photoconductor 4 becomes X1, but after the life detection P of the photoconductor, that is, the life detection signal is output from the photoconductor life detection means 63. If the life of the image forming unit 34 that has been used is detected within the range of the predetermined number of copies N (at time 3Y3 in FIG. 9A), the unit life detecting means 60 A life detection signal is output and is input to the AND circuit 62 and the first display 61. As a result, the first display 61 is turned on, and the life detection signals from the two detection means 60 and 63 are input to the AND circuit 2, and the AND output is output from the AND circuit. Then, the second display 64 is also turned on. Thus, by turning on both indicators 61 and 64, the operator can know that both the photoconductor and the image forming unit 34 should be replaced. This is the first mode.
After the point P, even if the photoconductor life detection signal is output, there is no AND output from the AND circuit 62 until the unit life detection signal is output, and both the indicators 61 and 64 remain off. I do.

If the life of the image forming unit is not detected within the range until the counter 200 counts the predetermined number N while the photoconductor life detection signal after the point P is output, the counter 200 counts N times. When finished, the counter 2
The 00 output is input to the second display 64, and only the second display 64 lights up, indicating that only the photoconductor 4 should be replaced. This is the second mode.

Next, in the embodiment shown in FIG. 11, the output of the photoconductor life detecting means 63 shown in FIG. 6 is also input to the counter 200, and the output is provided on the display panel of the copying machine. It is configured to be input to the 3 display 164, and the other configuration is the same as the configuration of FIG.

When only the life of the image forming unit 34 is detected (1Y3, 2Y3 in FIG. 9A and 1Y3, 2Y3, 3Y3 in FIG. 9B), that is, in the third mode, the unit life The output of the detection means 60 becomes H level, which is branched and inputted to each of the AND circuits 162 and 62. At this time, the output of the photoconductor life detecting means 63 is at the L level, one of which is branched to the counter 200, and the other is directly to the second AND circuit 62.
The other one is inverted by the inverting circuit 65, becomes H level, and is input to the first AND circuit 162. Thus, since the input to the counter 200 is at the L level, the counter 2
At 00, the operation is not started, and only the output of the first AND circuit 162 is at the H level, whereby only the first display 61 is turned on, indicating that only the image forming unit 34 should be replaced.

In the first mode, the photoconductor life detecting means 63 detects the photoconductor life at the point P in FIG.
At this time, the output from the detecting means 63 becomes H level,
This is input to the counter 200 and the second AND circuit 62. At the same time, this output goes to the L level via the inverting circuit 65 and is input to the first AND circuit 162. Thus, the counter 200 starts operating and counts each time a copy operation is performed. Thereafter, if the life of the imaging unit 34 is detected before the predetermined number of copies N has been executed, the output from the detection unit 60 becomes H level and the second
The H level output from both detection means 63 and 60 is input to the AND circuit 62, and the second display 64 is turned on. On the other hand, the first AND circuit 162 has the L level output from both detection means 63 and 60 and the H level.
Since the output of the level is input, the first display 61 maintains the light-off state. At this time, since the counter 200 has not finished counting N, the third display 164 is displayed from the counter 200.
No input is made, and the display 164 remains off.
In this manner, only the second display 64 is turned on, and an indication is given that both the photoconductor 4 and the image forming unit 34 should be replaced.

If the life of the image forming unit 34 is not detected by the time when the photoconductor life is detected at the time point P and the counter 200 starts to operate and before the predetermined number of copies N is executed,
The output from the counter 200 is input to the third display 164,
At this time, since the outputs from the AND circuits 62 and 162 remain at the L level, only the third display is turned on, and an indication that only the photoconductor is to be replaced is displayed. This is the second mode.

As described above, in the embodiment shown in FIGS. 10 and 11, only the respective indicators are turned on for each mode, so that there is no possibility that the operator mistakes the display contents.

In the embodiment shown in FIG. 10 and FIG. 11, when the life of the image forming unit is detected within a predetermined number of image forming times after the life of the latent image carrier is detected, the image forming unit and the latent image carrier are detected. Display means for indicating that the body should be replaced, and display for indicating that the latent image carrier should be replaced after the predetermined number of image formations when the life of the image forming unit is not detected within the range. Means, and a display means for displaying that the image forming unit should be replaced when the life of the image forming unit is detected outside the range and the life of the image forming unit is detected, and a display 61, 64; 164, an AND circuit 2, 162 , A counter 200 and an inversion circuit 65.

In each of the embodiments described above, the operator exchanges necessary elements according to the display on each of the display units 61, 64, and 164. When only the image forming unit 34 is exchanged, as shown in FIG. Is lifted, and the photoconductor 4 remains in the lower structure 52, the unit 34
Only can be easily removed. Conversely, when exchanging both the photoconductor 4 and the image forming unit 34, if the photoconductor 4 can be lifted together with the unit 34 as shown in FIG. Structure 51
Advantageously, it can be removed from In the state shown in FIG. 1, the lower part of the photoreceptor 4 serves as a copy paper transport path. When the copy paper jams in this transport path, as shown in FIG. If the photosensitive member 4 as well as the photosensitive member 4 can be lifted upward, the jam processing can be easily performed, which is convenient. Such a request:
This can be realized by the embodiment described below.

1 to 3, 12 and 13, the copying machine main body 1 is provided with first and second operation levers 70 and 71 which can be operated from the outside.

The first lever 70 has a connecting member as shown in FIG.
Lever hook 74 is integrally connected via 73
74 is rotatably supported by a pivot pin 75 fixed to a side plate frame (not shown) of the upper structure 51. When the upper structure 51 is in the closed state as shown in FIG. 1, the lever hook 74 engages with the lock pin 76 fixed to the column 100 of the lower structure 52, and the upper structure 51 is connected to the lower structure 52. Locked against.

On the other hand, a rotating member 78 is integrally fixed to the second lever 71 via a connecting member 77, and the member 78 is also rotatably supported by the pivot pin 75. One end of a connecting link 79 is pivotally connected to a lower portion of the rotating member 78, and the other end of the link 79 is pivotally connected to a photoreceptor shaft hook 80. The photoreceptor shaft hook 80 is rotatably supported by a support pin 81 fixed to a side plate frame of the upper structure 51 located on the rear side (rear side) of the photoreceptor 4. When closed as shown in FIG. 1, the photoreceptor shaft hook 80 is engaged with the photoreceptor shaft 54.

FIG. 13 shows each lever provided on the back side of the photoconductor 4.
Although the respective elements related to 70 and 71 are shown, as can be seen from FIGS. 2 and 3, similar elements denoted by the same reference numerals are also provided on the front side of the photoreceptor 4, Each photoreceptor axis of body 4
The photoreceptor shaft hooks 80 are engaged with 54, respectively. 2, only a part of the side plate frame 101 of the upper structure 51 that supports the front photoreceptor shaft hook 80 is shown.

As described above, when the image forming unit 34 reaches the end of its life and only this unit is to be replaced, the operator grasps the second operation lever 71 and pulls it in the direction of arrow C (FIGS. 1 and 13). As a result, the rotating member 78 also rotates in the same direction, and the connecting link 79 moves rightward in FIG.
Is drawn to. For this reason, the photoreceptor shaft hook 80 is
(See FIG. 2).

At this time, the connecting member 77 of the second operating lever 71 is located closer to the inside of the copying machine body than the connecting member 73 of the first operating lever 70, and the two members 77, 73 are in contact with or adjacent to each other. Therefore, when the second operating lever 71 is pulled in the direction of arrow C, the connecting member 73 of the first operating lever 70 is also entrained in the same direction. Get off.

If the upper structure 51 is rotated in the direction of arrow A while holding the second operation lever 71 in the above-described state, the photosensitive member 4 is supported by the support member 55 as shown in FIG. Structure
Only the imaging unit 34 is lifted up together with the upper structure 51 while being left at 52. Therefore, the operator can easily replace only the image forming unit 34 as indicated by the display.

When an indication that both the image forming unit 34 and the photoconductor 4 should be replaced is displayed and an indication that the copy paper has jammed in the copy paper transport path is displayed, the operator operates the first operation lever. Grab 70 and rotate it in the C direction. As a result, the lever hook 74 comes off the lock pin 76. However, at this time, the connecting member 73 of the first operating lever 70
Is located outside the connecting member 77 of the second operating lever 71 (right side in FIGS. 2 and 3), so that the connecting member 77 does not operate even when the first operating lever 70 is rotated. No, so the photoreceptor shaft hook 80 remains engaged with the photoreceptor shaft 54.

In this state, while holding the first operation lever 71, the upper structure
When the hook 51 is lifted, the hook 80 is engaged with the photoreceptor shaft 54, so that the photoreceptor 4 is also lifted while being supported by the upper structure 51 as shown in FIG. Therefore, the operator can easily exchange both the image forming unit 34 and the photoconductor 4 or can easily process the jammed paper in the copy paper conveyance path opened as the photoconductor 4 moves upward. .

In the embodiment shown in FIG. 14, one operating lever 170 corresponding to the first operating lever 70 shown in FIG. 13 is provided, but the second operating lever is not provided. Instead, the connecting link 179 is connected to the plunger of the solenoid 82.

When an indication that only the image forming unit 34 should be replaced is displayed, the solenoid 82 is energized by the detection signal, whereby the connecting link 179 is pulled in the direction of arrow D. Therefore, the photoreceptor shaft hook 80 comes off the photoreceptor shaft 43. In this state, when the operator pulls the operation lever 170 in the direction of arrow C, the lever hook 74 is disengaged from the lock pin 76, and thus the upper structure 51 is lifted while holding the lever 170.
As shown, only the image forming unit 34 is lifted while the photoconductor 4 is left on the lower structure 52, and can be replaced.

When an indication to replace both the image forming unit 34 and the photoreceptor 4 is given or when a jam signal is generated, the solenoid 82 is not energized. Therefore hook 80
Remain engaged with the photoreceptor shaft 43. In this state, if the operation lever 170 is pulled in the direction of arrow C and the upper structure 51 is lifted, the photoconductor 4 is also lifted together with the upper structure 51 as shown in FIG. Replacement or jam clearance work can be easily performed.

In the embodiment shown in FIG. 14, the operator can perform a predetermined operation simply by operating the same operation lever 170 in any case, and can prevent an erroneous operation.

Next, specific examples of the photoconductor life detecting means and the image forming unit life detecting means described above will be described.

As described above, the photoconductor life detecting means counts the number of copies each time each copy sheet is processed during the copying operation, and when the count reaches a predetermined value, as described briefly above. Means for generating a photosensitive member life signal can be employed (for this, see, for example, Japanese Utility Model Laid-Open No. 52-46838). This is an example of an image carrier life detecting unit that detects the life of the latent image carrier by detecting the number of formed images.

Alternatively, a photoconductor life detecting unit that counts the number of rotations of the photoconductor 4 and generates a photoconductor life signal when the counted value reaches a predetermined number may be used. This is an example of an image carrier life detecting unit that detects the life of the latent image carrier by detecting the rotation speed of the latent image carrier.

Furthermore, paying attention to the fact that the surface potential of the photoconductor 4 changes with the deterioration of the photosensitive layer, the surface potential of the photoconductor after charging, the surface potential after exposure, or the surface potential after static elimination is measured.
By comparing this with the reference potential, it is possible to detect the deterioration of the photoconductor and use a detection means for generating a photoconductor life detection signal. FIG. 15 and FIG.
The detecting means described below with reference to the drawing is an example of an image carrier life detecting means for detecting the life of the latent image carrier by detecting deterioration of the latent image carrier.

That is, in the example shown in FIGS. 15 and 16, the support 83 of the photoconductor 4 is composed of an insulator, the conductive layer 84 is laminated on the outer peripheral surface thereof, and the photosensitive layer 85 is further coated thereon. To form the photoconductor 4. Then, the ground brush 86 and the conductive contact member 86a are respectively brought into contact with the conductive layer 84 exposed at both end regions, and a detection circuit 86b similar to a normal disconnection detection circuit is connected to both. When the photoconductor 4 is new,
The ground brush 86 and the conductive contact member 86a are in a conductive state via the conductive layer 84. However, with the use of the photoreceptor 4, the conductive layer 84 in contact with the contact member 86a is worn, and the conductive state is finally interrupted. Leads to. This is detected by the detection circuit 86b, and a photoconductor life detection signal is generated.

By using the image carrier life detecting means for detecting the life of the latent image carrier without depending on the number of replacements of the image forming unit as described above, the life of the latent image carrier can be accurately detected, and the latent image In a state where the carrier can be used for a sufficiently long time, a problem of replacing the latent image carrier can be prevented.

Next, the life detecting means of the image forming unit 34 will be described.

As shown in FIG. 1, a developing case in the developing device 8
A detection plate 87 is rotatably supported inside the unit 10. This detection plate
87 is placed on the toner 9 inside the developing case 10.
Therefore, in the initial state where a large amount of toner 9 is present, the detection plate
87 keeps a substantially horizontal posture as shown by the solid line in FIG. When the toner 9 is sequentially consumed, the detection plate 87 also rotates clockwise in FIG. 1 and finally tilts as shown by a chain line in FIG. With this movement, the detection plate
Since the projection 88 of the 87 also rotates, this rotation is detected by a detection device such as a microswitch or an optical sensor (not shown), and it is detected that the remaining amount of toner has become a predetermined amount or less.

Alternatively, although not shown in FIG. 1, an agitator for stirring the toner may be provided in the developing case 10 to detect that the remaining amount of toner has become less than a predetermined amount due to the fluctuation of the rotation torque. That is, when the amount of toner in the case 10 is large, the rotation torque of the agitator is large, but when the amount of remaining toner is small, the rotation torque of the agitator is also reduced. Judge.

As described above, the remaining amount of toner in the developing case 10 may be measured by various methods, and when the remaining amount becomes equal to or less than a certain level, a life detection signal of the image forming unit may be generated.

Similarly, the life of the cleaning case 20 can be detected by detecting the amount of toner accumulated in the cleaning case 20. For example, in the example shown in FIG. 1, the feeding roller 8 for feeding the toner removed from the photoreceptor 4 to the toner container 20a of the case 20
Although 9 is provided, the toner amount can be detected by the fluctuation of the rotation torque. Alternatively, a rotating blade (not shown) may be provided in the toner storage section 20a, and the life of the cleaning device may be detected based on the fluctuation of the rotating torque. That is, when the gradually increasing rotational torque reaches a predetermined value, a life detection signal is generated.

Further, as shown in FIG. 1, a rubber member 90 is provided in an opening formed in the upper wall of
As the amount of toner in 20a increases, the rubber member 90 can be pushed upward, and the protrusion 90a can be detected by a microswitch or an optical sensor (not shown) to detect the life of the cleaning device.

The developing device 8 and the cleaning device 18 are each provided with the above-described detecting means, and these are used as the image forming unit life detecting means. When any one of them outputs a detection signal, this may be used as the unit life detecting signal. However, only one of the various detecting means described above may be used as the unit life detecting means.

When the life of the developing device is detected, a near-end detection signal is output before the generation of the above-mentioned unit life detection signal. At this time, as shown in FIG. Can be drawn out to the near side, the spare toner 9a held therein is dropped into the case 10, and a copying operation is performed by the spare toner until a unit life detection signal is generated. . According to this configuration, there is an advantage that when a new operating unit is not available, copying can be performed with the spare toner until the new operating unit is ordered.

Although the case where the latent image carrier is formed of a drum-shaped photoconductor has been described above, an image forming apparatus in which the carrier is configured as a belt-shaped photoconductor or a dielectric drum (or belt), and various other Naturally, the present invention can be applied to an image forming apparatus. In the example shown in the figure, two processing means, mainly a developing device and a cleaning device, are integrally assembled to form an image forming unit detachable from the copier main body. However, this is merely an example. At least one of the process means including these devices
One can form an image forming unit. For example, an image forming unit including only a developing device, an image forming unit including only a cleaning device, or an image forming unit including only a charging device and a transfer device may be used.
The image forming unit assembled above may be used. In such a case, the unit life detecting means for detecting the life of these image forming units and the display means may be provided in the same manner as the configuration of the embodiment. The number of image forming units is not limited to one, but may be plural. In this case, for example,
When the service life of each image forming unit is detected independently (that is, in a state where the service life of the latent image carrier is not detected), the exchange means of only each image forming unit is displayed by the display means, and the latent image carrier is replaced. When the life is detected, the display means may be used to display a display for replacing both the image forming unit and the latent image carrier whose life has been detected thereafter, and these may be replaced together.

Advantageous Effects According to the image forming apparatus described in claims 1 and 2, there is an economical loss that the latent image carrier is discarded in a state where it can still be used for a long time. Therefore, the number of replacements of the latent image carrier and the image forming unit can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of the center of an electronic copying machine according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views of the electronic copying machine taken on a front side of FIG. Shows the state when the upper structure is lifted while the photoconductor is left on the lower structure.
FIGS. 4 (a) and 4 (b) are views showing the state when the photosensitive member is lifted up by supporting the photosensitive member on the upper structure, and FIGS. 4 (a) and 4 (b) are explanatory views for explaining the principle in one embodiment of the present invention. And the sixth
The figure shows a block diagram for implementing this, FIG. 7 (a),
(B) and FIGS. 8 (a) and (b) are explanatory diagrams of the principle of a more preferred embodiment, and FIGS. 9 (a) and (b) are explanatory diagrams of the principle of still another embodiment, FIGS. FIG. 11 shows FIG. 9 (a),
FIG. 12 is a block diagram for implementing the configuration shown in FIG.
The figure shows a perspective view of the appearance of the copier, which clearly shows the operation lever.
The figure is a perspective view showing the operation lever and its related configuration,
FIG. 14 shows another embodiment, and is a perspective view similar to FIG.
FIG. 15 is a perspective view showing an example of the photosensitive member life detecting means, FIG. 16 is a longitudinal sectional view of the photosensitive member shown in FIG. 15, and FIG. 17 is a sectional view of a developing device provided with spare toner. 34 image forming unit, 60 unit life detecting means 63 image carrier life detecting means

Continuation of front page (72) Inventor Hisao Murayama 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (56) References JP-A-61-166554 (JP, A)

Claims (2)

(57) [Claims] An image forming apparatus for forming a visible image on a surface of a latent image carrier by a plurality of process means, transferring the visible image to a transfer material, and cleaning the surface of the latent image carrier after transfer. An image forming unit comprising at least one process means and a latent image carrier, each of which is detachably attached to the image forming apparatus main body, and a unit life detecting means for detecting the life of the image forming unit; An image forming apparatus provided with image carrier life detecting means for detecting the life of the carrier, wherein the image carrier life detecting means detects the number of images formed, detects the rotational speed of the latent image carrier, or detects the number of rotations of the latent image carrier. Means for detecting the life of the latent image carrier by detecting deterioration; display means for displaying that the image forming unit should be replaced when the life of the image forming unit is detected; and detecting the life of the latent image carrier. , And product Means for prohibiting the indication that the latent image carrier should be replaced when the life of the image unit has not been detected, and the life of the image forming unit has been detected since the life of the latent image carrier has been detected. An image forming apparatus provided with a display unit for displaying that both the image forming unit and the latent image carrier are to be replaced. 2. An image forming apparatus for forming a visible image on the surface of a latent image carrier by a plurality of process means, transferring the visible image to a transfer material, and cleaning the surface of the latent image carrier after the transfer. An image forming unit comprising at least one process means and a latent image carrier, each of which is detachably attached to the image forming apparatus main body, and a unit life detecting means for detecting the life of the image forming unit; In an image forming apparatus provided with an image carrier life detecting means for detecting the life of the carrier, when the life of the image forming unit is detected within a predetermined image forming frequency range after the life of the latent image carrier is detected. Display means for displaying that both the image forming unit and the latent image carrier should be replaced, and when the life of the image forming unit is not detected within the range, the latent image carrier is formed after the predetermined number of image formations. Change your body A display unit for displaying that the image forming unit is out of the range, and when the life of the image forming unit is detected, a display unit for displaying that the image forming unit should be replaced. Image forming device.