JP2001042628A - Developing device, and image forming device provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device which successively and accurately detects developer quantity in a developer container, at a low cost, and an image forming device provided with the developing device. SOLUTION: In this developing device, provided with a pixel count part detecting the toner quantity in a toner container 4 as occasion demands, based on the information quantity of the image information and with magnetic sensors 11 and 12 detecting at least one of the toner level in the toner container 4, toner quantity detected by the pixel counting part is corrected, so that the toner quantity detected by the pixel counter becomes the level when the toner quantity detected by the magnetic sensors 11 and 12 becomes the level respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device provided with a developer amount detecting means for detecting a developer amount in a developer container containing a developer, and an image forming apparatus provided with the developing device.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine, if the image forming apparatus is used for a long time, a photosensitive drum as a latent image carrier as an electrophotographic photosensitive member is replaced, and a developing device is replaced or developed. Replenish toner to the developing device, clean the charger,
It is necessary to replace the cleaning container in which the waste toner is stored, and to adjust the periphery of the photosensitive drum.

Therefore, conventionally, in an image forming apparatus using an electrophotographic image forming process, the electrophotographic photosensitive member and the process means acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachably mountable to the main body of the image forming apparatus. A process cartridge system is adopted.

According to such a process cartridge system, since the maintenance of the apparatus can be performed by the user himself, the operability of the image forming apparatus can be remarkably improved.

When this type of process cartridge runs out of toner in a developing device incorporated in advance, it is necessary to replace it with a new process cartridge.

Therefore, such a developing device is provided with a toner remaining amount detecting means (developing amount detecting device) for detecting the remaining amount of the toner container as the toner container which stores the toner as the toner is consumed. I have.

Here, a representative method of the toner remaining amount detecting means will be described below.

In such a toner remaining amount detecting means, the number of dots to be applied with toner (the number of pixels) obtained when the image to be printed (image information) is developed into a dot map divided for each pixel is determined. Counting and integrating, multiplying by the amount of toner used per pixel to calculate the used toner amount (consumed developer amount), subtracting it from the total amount of toner in the toner container, and calculating the current toner remaining amount in the toner container There is known a required method, a so-called pixel count method.

In the toner remaining amount detecting means, a magnetic sensor is brought into contact with the toner container to detect the magnetic permeability of the toner around the magnetic sensor.
A method for detecting the presence or absence of toner in the toner container or the amount of toner in the toner container at the position level of the magnetic sensor,
A so-called magnetic sensor system is known.

Further, the toner remaining amount detecting means is a developer amount detecting member provided in the toner container so as to follow the upper surface (toner level) of the toner in the toner container as the toner is consumed. 2. Description of the Related Art A method of detecting the position of a float to detect the remaining amount of toner in a toner container, a so-called float method, is known.

[0011]

However, in such a developing device, it is necessary to accurately and successively detect the remaining amount of toner in the toner container from the start of use of the process cartridge to the end of use when the toner runs out. However, it is difficult to use the above method alone.

That is, in the pixel counting method,
Even if the number of pixels (the number of pixels) is the same, the amount of toner used may be different due to a printing pattern or an environmental difference, and a detection error when the amount of toner becomes small may increase.

The magnetic sensor system is suitable for stepwise detection, but when the amount of toner in the toner container becomes small, it is necessary to arrange a large number of magnetic sensors in order to make the detection closer to the sequential detection. , Resulting in increased costs.

Further, in the case of the float type, since the shape of the toner container, the stirrer or the like is provided in the toner container, or in order to maintain the developing performance, the toner in the toner container is floated until the toner runs out. May not be able to follow the toner level.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a developing device capable of sequentially and accurately detecting the amount of a developer in a developer container at low cost or an image forming apparatus provided with the developing device.

[0016]

Means for Solving the Problems The main invention according to the present application is a developing device for visualizing a latent image by applying a developer to a latent image carrier that carries a latent image corresponding to image information. A developer container containing a developer, and a developing device including a developer carrier that is arranged to face the latent image carrier and carries the developer supplied from inside the developer container.
First developer amount detection means for detecting the amount of developer in the developer container at any time based on the information amount of the image information, and second developer capable of detecting at least one level of the amount of developer in the developer container The first developer amount detection means so that when the amount of developer detected by the second developer amount detection means is at the above level, the amount of developer detected by the first developer amount detection means is at the above level. Wherein the amount of developer detected by the developing device can be corrected.

According to another aspect of the present invention, there is provided a process cartridge which holds at least a developing device and a latent image carrier and is detachably supported by an image forming apparatus main body. Is a process cartridge characterized by the above-mentioned.

Further, the invention according to another main application of the present invention is:
An image forming apparatus that records an image formed by a series of image forming processes on a recording medium, wherein the developing device includes:
Alternatively, an image forming apparatus including the process cartridge described above.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) First, a first embodiment of the present invention will be described.

FIG. 1 is a cross-sectional view when the process cartridge B according to the present invention is mounted on the main body of the image forming apparatus A, and FIG. 2 is a cross-sectional view of the process cartridge B.

The process cartridge B is inserted in the direction indicated by the arrow X by opening the opening / closing cover F1 of the main body A of the image forming apparatus.

The copying process (image forming process) in the image forming apparatus A is as follows.

In the image forming apparatus A, first, an image signal (image information) sent to the main body of the image forming apparatus A, which is a terminal, is developed by the signal conversion section H into bitmap data.

The scanner unit S is driven based on the bitmap data, and emits a laser beam (indicated by a two-dot chain line in FIG. 1).

The laser light is uniformly applied to the surface by the charging roller 2 and is irradiated onto the photosensitive drum 1 serving as a latent image carrier rotating in a predetermined direction to form a latent image on the photosensitive drum 1.

Next, a latent image is formed on the photosensitive drum 1 by a developing device 7 on the latent image portion of the photosensitive drum 1 irradiated with the laser beam.
The toner, which is a developer, is transferred to be visualized as a toner image (developer image).

On the other hand, the transfer material P is sent from the sheet feeding tray F2 to a position below the photosensitive drum 1 by the sheet feeding mechanism Q, and the toner image on the photosensitive drum 1 is transferred to the transferred transfer material P by the transfer device T. Is done.

Thereafter, the transfer material P on which the toner image has been transferred is fixed on the transfer material P by the fixing device K, and is sent out to the paper output tray F3 by the paper output mechanism I.

On the other hand, the toner remaining on the photosensitive drum 1 without being transferred is scraped off by the cleaning blade 5 into the waste toner container 9 and removed.

Next, the developing device 7 provided in the image forming apparatus A will be described.

The developing device 7 includes a toner container 4 serving as a developer container for accommodating toner, and a developing sleeve disposed opposite to the photosensitive drum 1 and carrying a toner supplied from the toner container 4. 3, a pixel count unit 31 as first developer amount detecting means capable of detecting the amount of toner in the toner container 4 at any time based on the amount of image information, and two levels of the amount of toner in the toner container 4 can be detected And magnetic sensors 11 and 12 as second developer amount detecting means.

In the developing device 7, the toner (developer) T is stirred by the T stirrer 6 as a developer stirring member in the toner container 4 and sufficiently loosened by the D stirrer 8. Then, the toner image (developer image) is formed by moving to the latent image portion on the photosensitive drum 1 irradiated with the laser beam.

Next, detection of the amount of toner in the toner container 4 in the present embodiment will be described with reference to FIGS.

In the present embodiment, the pixel count method is employed for the first developing amount detecting means, and the magnetic sensor method is employed for the second developing amount detecting means. The amount of developer detected by the first developer amount detecting means can be corrected so that the amount of developer detected by the first developer amount detecting means at the two levels of the toner amount in the toner container becomes the above level. .

In this embodiment, when the process cartridge B is mounted on the image forming apparatus A, the magnetic sensors 11 and 12 disposed inside the image forming apparatus A
The toner container 4 is brought into contact with the toner container 4 by a and 12a.

The magnetic sensors 11 and 12 are connected to the toner container 4
Through the sensor, the magnetic permeability of the toner in the toner container 4 is detected, and a signal corresponding to the amount of toner in the toner container 4 or a signal indicating the presence or absence of the toner is output based on the magnetic permeability.

The signals output from the magnetic sensors 11 and 12 are processed by a signal calculation unit (not shown), and the value of the remaining amount of toner in the toner container 4 is output.

When the toner amount is almost full (FIG. 3A)
Sends a signal indicating that the magnetic sensors 11 and 12 have toner.

When the toner consumption in the toner container 4 is advanced and the toner level comes near the magnetic sensor 11 (FIG. 3)
(B)) Since the magnetic sensor 12 sends a signal indicating that there is no toner and the magnetic sensor 11 sends a signal indicating that toner is present, the arithmetic unit outputs that the remaining amount of toner in the toner container 4 is close to the magnetic sensor 11. .

Further, when the toner in the toner container 4 is consumed (FIG. 3C), since the magnetic sensors 11 and 12 both output a signal indicating that no toner is present, the pixel count of the first developer amount detecting means is beyond that. , The remaining amount is detected.

In the first developer amount detecting means, an image signal (image information) is developed into bitmap data divided for each pixel, and the number of pixels (pixel number) where toner is transferred is counted. Then, the used integrated amount (consumed developer amount) is calculated by multiplying the counted integrated value by the amount of toner consumed per pixel, and the value is calculated from the toner remaining amount value at which the remaining amount detection by the pixel count method starts. By subtracting the value, the remaining amount of toner in the toner container 4 is obtained.

In this embodiment, the magnetic sensors 11 and
It has been described that the remaining amount detection by pixel count is activated after the remaining amount detection by the unit 12. However, from the time when the toner is full to the time when the toner runs out, the detection by the magnetic sensor and the pixel count are performed at the same time, and the accurate toner remaining value is calculated by the signal calculation unit Or a method of performing appropriate arithmetic processing so as to output data.

That is, in the graph of FIG. 5A, when the horizontal axis indicates the number of accumulated pixels and the vertical axis indicates the remaining amount of toner, it is assumed that a solid line a is obtained when a certain reference image pattern is continuously printed.

However, when the density changes due to the operating environment or various image patterns are printed, the amount of toner consumed per pixel also changes, and this relationship does not always follow the solid line a (dashed line b or (It may follow the broken line c).

Therefore, the detection of the remaining amount by the magnetic sensor is used together with the pixel count, and correction is made for each key point.

First, when the standard pattern is continuously printed in the graph of FIG.
Sets the remaining toner value at the time when the “toner out” signal is output to t11,
At t12, the corresponding accumulated pixel numbers are P11 and P12.

When the correction is made, the cumulative number of pixels is P
11, P12, or the toner remaining amount is t12,
Assume that the output signal of the magnetic sensors 11 and 12 is reversed from “with toner” to “no toner” at t11.

As shown in FIG. 4, the inclination of the solid line a is stored in the ROM 30 mounted on the main body of the image forming apparatus A or the process cartridge B. The signal operation part 3
Output to 2.

The signal calculating section 32 stores the remaining toner values t12 and t11 and the number of pixels P12 and P11 serving as thresholds. The remaining toner values obtained through the ROM 30 from the inputs from the magnetic sensors 11 and 12 and the pixel count 31 are stored. The amount value is input and compared with the threshold value, and the value of (accumulated pixel number, remaining amount of toner) is corrected.

The calculation result processed by the signal calculation section 32 is output to the display section 33 of the image forming apparatus A main body.

For example, consider a case where an image having a high density is continuously printed.

In the graph shown in FIG. 5B, the relationship between the number of pixels and the remaining amount of toner is such that the inclination of the solid line a It becomes larger and follows the dashed line b.

For a while after the toner is full, a toner remaining amount corresponding to the number of pixels is output along the solid line a.

However, since the consumption of toner is fast, the toner surface exceeds the magnetic sensor 12 when the value of (accumulated pixel number, remaining amount of toner) is (P1, t1) before the number of pixels reaches P12. The sensor 12 outputs “no toner”.

Here, the arithmetic unit C changes the (accumulated pixel number, remaining toner amount) from the current (P1, t1) to (P1, t1).
Modify to 2).

Then, the remaining toner output is
Starting from the point (p1, t12), the remaining amount of toner corresponding to the number of pixels is output at the same inclination as the solid line a.

Further, if similar toner consumption is continued, (P
The number of pixels P11 'to which the sensor 11 should react when the reference pattern is continuously printed starting from (1, t1).
Prior to (when P11 is changed from (P1, t1) to (p1, t12), P11 is also corrected to P11 ′), the sensor 11 outputs no toner at P2.

In this case as well, the calculation unit C similarly changes the (accumulated pixel number, toner remaining amount) from (P2, t2) to (P2, t1)
1), and the remaining output is changed to the point (p2, t1).
Starting from 1), the remaining amount of toner corresponding to the number of pixels is output at the same inclination as the solid line a.

Accordingly, the change in the remaining amount of toner when a high-density image is continuously printed from the process up to this point is represented by a thick line A shown in FIG. 5B.

The bold line A in the graph shown in FIG.
Since it is closer to the broken line b, the remaining amount detection using the magnetic sensor together with the remaining amount detection using only the pixel count is
It turns out that the accuracy is high.

Further, as the number of magnetic sensors is larger, the number of times of this correction can be increased, so that it is possible to sequentially and accurately detect the remaining amount of toner.

Conversely, consider the case where an image having a low density is continuously printed.

In the graph shown in FIG. 5C, the relationship between the number of pixels and the remaining amount of toner is smaller than the solid line a when the reference pattern is output, because the toner consumption per pixel is small. Smaller, following the dashed line c.

For a while after the toner is full, the remaining toner value corresponding to the accumulated pixel number is output along the solid line a.

However, even when the accumulated pixel number reaches P12, the remaining amount of toner is at t3, which is larger than t12, so that the sensor 12 outputs "toner present".

Then, the arithmetic unit C continues the pixel count until the magnetic sensor 12 outputs the absence of toner, but outputs the remaining amount of toner while maintaining the remaining amount of toner at t12.

When the number of pixels becomes P3 and the toner surface exceeds the magnetic sensor 12 and the magnetic sensor 12 outputs no toner, the arithmetic unit C starts from (P3, t12)
The remaining amount of toner corresponding to the number of accumulated pixels is output at the same inclination as the solid line a.

If the same toner consumption is continued, (P
(3, t12) The number of pixels P11 'to be reacted by the sensor 11 when the reference pattern is continuously printed starting from the starting point.
(When ((P3, t12)) becomes the starting point, P11 also becomes P
11 ′), the remaining toner amount is t11
Since there is more at t4, the sensor 11 has “toner present”
Is still output.

Then, the calculating section C calculates the remaining amount of toner as t11.
Count the number of pixels while maintaining.

At P5, the sensor t11 detects the absence of toner, and outputs an output reverse to the previous output.
The pixel count is continued until the magnetic sensor 11 outputs "no toner", but the remaining toner amount is output while the remaining toner amount is maintained at t11.

When the number of pixels becomes P4 and the toner surface exceeds the magnetic sensor 11 and the magnetic sensor 11 outputs "no toner", the arithmetic unit C starts from (P4, t11).
The remaining amount of toner corresponding to the number of accumulated pixels is output at the same inclination as the solid line a.

Accordingly, the change in the remaining amount of toner when a low-density image is continuously printed from the process up to now is represented by the thick line A in the graph shown in FIG. 5B.

The thick line A in the graph shown in FIG.
Since it is closer to the broken line b, the remaining amount detection using the magnetic sensor together with the remaining amount detection using only the pixel count is
It turns out that the accuracy is high.

Further, as the number of magnetic sensors increases, the number of times of this correction can be increased, so that the remaining amount of toner can be detected accurately one by one.

(Second Embodiment) Next, a second embodiment of the present invention will be described. Note that the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

The detection of the remaining amount of toner according to the second embodiment of the present invention will be described with reference to FIGS.

In this embodiment, the pixel count method is used for the first developer amount detecting means, and the float method is used for the second developer amount detecting means. The copying process is the same as in the first embodiment.

The detection of the remaining amount by the float 21 as the developer amount detecting member of the second developer amount detecting means will be described with reference to the sectional view of the cartridge of FIG.

The float 21 serving as a developer amount detecting member disposed on the upper surface of the toner in the toner container 4 includes an arm 22.
Is fixedly mounted on the rotating shaft 23 via a rotary shaft.

The rotation shaft 23 penetrates the toner container 4 and
Outside the container, it is connected to an angle sensor 24 such as a potentiometer.

Therefore, when the toner is consumed, the upper surface of the toner descends in the order of A, B, and C shown in FIG. 6, and the float 21 also follows the upper surface of the toner, and its rotation angle becomes an angle. Detected by sensor 24.

The signal from the sensor 24 is supplied to a ROM (not shown, not shown) in the process cartridge B or the image forming apparatus A.
(The relationship between the rotation angle of the float and the remaining amount of toner as shown in FIG. 7 is stored.)

In the present embodiment, it is necessary to arrange the float 21 on the upper surface of the toner before starting the detection of the remaining amount. For example, the user may manually operate the lever 21 from outside the container before mounting the cartridge. The method may be carried out in conjunction with the cartridge mounting operation, may be performed at the time of multiple rotation immediately after mounting, and is not particularly limited as long as the float 21 buried in the toner appears on the upper surface of the toner. .

Next, the remaining amount detection combined with the pixel counting method will be described.

When the toner is almost full (from FIG. 8A) until the float 21 comes on the rotation orbit of the T stirring rod 6 (FIG. 8B), the float 21 follows the lowering of the toner upper surface. And descend.

The subsequent movement of the float 21 is shown in FIG.
(A), (B), (C) and FIG. 10 showing the time change of the rotation angle of the float 21 will be described.

The float 21 on the upper surface of the toner
(FIG. 9A).
The toner is pushed up to the position (C) and falls again on the upper surface of the toner (FIG. 9A).

As described above, the toner 21 follows the upper surface of the toner while repeating swinging in the order of FIGS. 9A, 9B, 9C, and 9A, so that the float 21 or the arm The point at which 22 abuts on toner container 4 (FIG. 8C)
Then, the remaining amount detection by the float 21 ends.

When the angle sensor 24 detects the end point of the float 21, the remaining amount is detected by the pixel counting method.

In the pixel counting method, as in the first embodiment, the value obtained by (number of pixels) × (toner used amount per pixel) is subtracted from the remaining amount of toner when the remaining amount detection by the float 21 is completed. Thus, the remaining toner value is obtained.

In the present embodiment, it has been described that the remaining amount detection by the pixel count is activated after the remaining amount is detected by the float 21. However, from the time when the toner is full to the time when the toner runs out, the sensing by the float 21 and the pixel count are used together. Alternatively, a method may be used in which a signal calculation unit (not shown) selects and removes data so that an accurate toner remaining value is output, and performs an appropriate calculation process.

That is, in the graph of FIG. 12, the horizontal axis represents the cumulative number of pixels and the float rotation angle, and the vertical axis represents the remaining amount of toner.

When the reference image pattern is continuously printed while the toner surface is kept horizontal, it is assumed that the relationship between the pixel count, the float angle and the remaining amount of toner is obtained by A in the graph shown in FIG.

However, in practice, the difference between the remaining amount of toner due to the pixel count and the remaining amount of toner due to the float angle is caused by a change in the amount of toner consumed due to the image pattern, a change in the density due to the operating environment, a temporary suspension of the float due to toner collection, and the like. May occur.

For example, the float is shown in FIG.
The range up to the state of FIG.

In this area, when the toner is collected and the float is stopped, the pixel count is counted without being affected by the environmental fluctuation, and the value becomes Pa. The quantity Pa1 is determined.

However, since the float is stopped on the toner surface, the float angle becomes Fa ', which is smaller than Fa obtained when the float normally follows.
Is obtained from A in the graph shown in FIG.

Therefore, in the signal operation section, Pa1 and Fa'1
Is used, and t1 is output as the result toner remaining amount.

Here, it is conceivable that the pixel count is advanced in spite of the state where the float is stopped due to the toner collection, and only the number of pixels enters the next area (BC).

As a countermeasure, the areas (AB) and (BC)
The number of pixels at the boundary of (in the state of FIG. 8B) is Pab
When the number of pixels reaches Pab, the float is
If the float angle is smaller than the float angle Fab when the robot follows the entire surface of the toner without stopping until the state of (B), the pixel count is set to Pab until the float angle becomes Fab.
Stop as it is.

When the float angle becomes Fab, the pixel count is restarted.

By this processing, the pixel count does not advance beyond the area even when the float is stopped, and the notification that the remaining amount of toner suddenly changes even when shifting to the next area is not notified. Disappears.

Next, the state in which the float is in the state shown in FIGS. 8B to 8C is defined as the range of the area (BC) in FIG.

In this area, the remaining float detection, which directly detects toner having a uniform density due to agitation and flow, is more accurate. Therefore, the remaining toner amount Pb1 obtained from the number of pixels Pb is used to calculate the remaining toner amount from the float angle. Priority is given to the remaining toner amount Fb1.

When the float angle becomes Fbc, the number of pixels is corrected to Pbc, and the process proceeds to the next area (C).

By this processing, when the area (BC) is shifted to the area (C), there is no notification that the remaining amount of toner suddenly changes.

Since the float has reached the end point after FIG. 8C (the range of the area (C) in FIG. 12), the remaining toner amount is the remaining toner amount Pc1 obtained from the number of pixels Pc.

The determination of the transition from the area (AB) to the area (BC) is based on the fact that the toner flows at a uniform density at this boundary and the remaining amount detection by the float is more accurate. May be the time when the Fab in the state of FIG. 8B is detected.

Therefore, in the area (AB), the signal calculation section performs the pixel processing and the signal processing of the remaining toner amount by the float as averaging processing, and determines that the area (BC) has been shifted to the area (BC) when the float angle Fab is detected. Then, the signal processing is changed to the float priority.

The transition from the area (BC) to the area (C) is also made at the time when the float angle Fbc (the state shown in FIG. 8C) is detected, and the signal processing is changed from the float priority to the pixel count priority. .

Note that the method of signal processing is an example in the present embodiment and is not particularly limited.

As shown in FIG. 11, P and F in the graph shown in FIG. 12 are stored in the ROM 130 or the like mounted on the main body of the image forming apparatus or the process cartridge. The remaining amount of toner corresponding to the float angle from the angle sensor 24 that detects the float rotation angle is output to the signal calculation unit 132.

Further, the information on the float angle is stored in the signal calculation unit 1.
32, and is used for transition from the area (AB) to (BC) and transition from (BC) to (C).

The operation result processed by the signal operation unit 132 is
The image is output to the display unit 33 of the image forming apparatus main body.

[0116]

As described above, according to the invention of the present application, the amount of the developer in the developer container can be sequentially detected with high accuracy at low cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a process cartridge provided in the image forming apparatus of FIG.

FIG. 3 is a diagram for explaining remaining amount detection by a magnetic sensor according to the first embodiment of the present invention.

FIG. 4 is a diagram for explaining a control system for detecting a developer amount in a developer container according to the first embodiment of the present invention.

FIG. 5 is a diagram for describing detection of a developer amount in a developer container according to the first embodiment of the present invention.

FIG. 6 is a sectional view of a process cartridge according to a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a correlation between a float rotation angle and a remaining amount of toner according to a second embodiment of the present invention.

FIG. 8 is a diagram showing remaining amount detection by a float according to the second embodiment of the present invention.

FIG. 9 is a diagram illustrating the swing of the float in the remaining amount detection by the float in the second embodiment of the present invention.

FIG. 10 is a diagram illustrating a relationship between a rotation angle of a float and time according to a second embodiment of the present invention.

FIG. 11 is a diagram illustrating a control system for detecting the amount of a developer in a developer container according to the second embodiment of the present invention.

FIG. 12 is a diagram for describing detection of a developer in a developer container according to the second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 photosensitive drum (latent image carrier) 3 developing sleeve (developer carrier) 4 toner container (developer container) 7 developing device 11, 12 magnetic sensor (second developer amount detecting means) 11a, 11b spring 21 float ( (Developer amount detecting member) 22 Arm 23 Rotation axis 24 Angle sensor (Second developer amount detecting unit) 31 Pixel count unit (First developer amount detecting unit) A Image forming apparatus B Process cartridge P Transfer material (Recording medium) S scanner unit

Claims (6)

[Claims] 1. A developing device for visualizing a latent image by applying a developer to a latent image carrier that carries a latent image corresponding to image information, comprising: a developer container containing the developer; A developer carrying member that is disposed opposite to the image carrier and carries the developer supplied from the inside of the developer container, the developer amount in the developer container is determined based on the information amount of the image information. A first developer amount detecting means capable of detecting at any time, and a second developer amount detecting means capable of detecting at least one level of the developer amount in the developer container, wherein the detection is performed by the second developer amount detecting means. When the developer amount is at the above level, the amount of developer detected by the first developer amount detecting unit can be corrected so that the amount of developer detected by the first developer amount detecting unit becomes the above level. Developing device. 2. The first developer amount detecting means divides image information into predetermined pixels, and corresponds to an integrated value of the number of pixels to which the developer is to be applied, to a preset developer concentration level. 2. The developing device according to claim 1, wherein the amount of developer in the developer container is detected based on the amount of consumed developer calculated by multiplying the amount of developer per pixel unit. 3. A developer amount detecting means for detecting a developer amount in the developer container based on a position of a developer amount detecting member provided so as to follow a level position of the developer in the developer container. The developing device according to claim 1, wherein the developing device is configured to perform the following. 4. The second developer amount detecting means is configured to detect a developer amount in the developer container based on a magnetic permeability detected by a magnetic sensor for detecting a magnetic permeability of the developer in the developer container. The developing device according to claim 1 or 2, wherein the developing device is provided. 5. The process cartridge according to claim 1, wherein the process cartridge holds at least a developing device and a latent image carrier and is detachably supported by an image forming apparatus main body. A process cartridge comprising a device. 6. An image forming apparatus for recording an image formed by a series of image forming processes on a recording medium,
An image forming apparatus comprising: the developing device according to claim 1; or the process cartridge according to claim 5.