JP2001022252A - Process cartridge and electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process cartridge and an electrophotographic image forming device made compact and capable of forming a high-quality image. SOLUTION: This process cartridge which can be loaded in/unloaded from an electrophotographic image forming device main body is provided with a developer storage part 4, a developer amount detection means 6, a detection means cleaning member 36 actuated when driving is transmitted from the electrophotographic image forming device main body in a state where the process cartridge is loaded in the electrophotographic image forming device, and a developer stirring member 3. Then, the stirring speed of the member 3 is varied in accordance with the developer amount in the storage part 4. Relating to this electrophotographic image forming device in which the process cartridge can be loaded, the driving speed of the member 3 is changed in accordance with the developer amount in the storage part 4 of the process cartridge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus for forming an image by an electrophotographic method, and a process cartridge detachably mountable to the electrophotographic image forming apparatus.

Here, as an electrophotographic image forming apparatus,
For example, an electrophotographic copying machine, an electrophotographic printer (for example, L
ED printers, laser beam printers, etc.), electrophotographic facsimile machines, and electrophotographic word processors.

A process cartridge is a cartridge in which at least one of a charging unit, a developing unit, and a cleaning unit and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachably mountable to an electrophotographic image forming apparatus main body. Or a cartridge in which at least the developing means and the electrophotographic photosensitive member are integrally formed, and this cartridge is detachable from the main body of the electrophotographic image forming apparatus.

[0004]

2. Description of the Related Art Conventionally, as shown in FIG. 8, an electrophotographic image forming apparatus such as a laser beam printer is used as an image carrier in which light L corresponding to image information is uniformly charged by a charging means 7. For example, a latent image is formed by irradiating the cylindrical electrophotographic photosensitive member 1, and a developer (including toner) as a recording material is supplied to the latent image using a developing unit 10 to visualize the latent image. And the electrophotographic photosensitive member 1 by the transfer means 12
Is transferred to the recording medium P, and then fixed by the fixing unit 13 to form an image on the recording medium P.
Further, the surface of the electrophotographic photosensitive member 1 is cleaned by the cleaning means 8. The developer accommodating section 4 is connected to the developing means 10, and the developer in the developer accommodating section 4 is consumed by forming an image.

Conventionally, in an electrophotographic image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is used as an electrophotographic image forming device. A process cartridge system that can be attached to and detached from the forming apparatus main body is employed. According to this process cartridge system, maintenance of the apparatus can be performed by the user himself without relying on a service person, so that operability can be remarkably improved. That is, when the developer runs out, the user can always form a stable image by replacing the process cartridge. Therefore, this process cartridge system is widely used in electrophotographic image forming apparatuses.

In the image forming apparatus of the process cartridge type, it is necessary to display to the user to prepare the process cartridge before the developer in the process cartridge runs out and the image cannot be formed. The amount of the developer in the developer storage section 4 of the cartridge is sequentially detected.

As described above, as a developer amount detecting means used for sequentially detecting the developer amount in the developer accommodating portion,
There is a so-called planar antenna.

That is, as shown in FIG. 9, for example, the planar antenna 6 has an electrode pattern 20 composed of a pair of input-side electrodes 21 and output-side electrodes 22 having portions arranged at regular intervals on a substrate. The planar antenna 6 is provided with a developer storage portion of a process cartridge along a direction in which the contact area with the developer changes as the amount of the developer decreases, such as the side surface of the developer storage portion 4 in FIG. 4. When the developer amount is large and the contact area with the planar antenna 6 is large, the capacitance between the electrodes 21 and 22 of the planar antenna 6 is high, the developer amount is small, and the contact area with the planar antenna 6 is small. Electrode 2
The capacitance between 1 and 22 is reduced. Therefore, by measuring the capacitance of the planar antenna 6, the amount of the developer in the developer accommodating section 4 can be sequentially detected. Although such a planar antenna 6 has fine irregularities due to the electrode pattern 20, it can be covered with, for example, a protective film and has a substantially planar shape.

The surface of the planar antenna 6 needs to be cleaned at regular intervals in order to detect the amount of the developer in the developer accommodating section 4 based on the presence or absence of the developer on the surface. If this surface is not cleaned, even if the amount of developer in the developer accommodating portion 4 is reduced,
Since a certain amount of output is obtained by a small amount of the developer remaining on the surface of the planar antenna 6, the output of the planar antenna 6 varies greatly with respect to the same amount of the developer, and the measurement accuracy of the developer amount is reduced. Will drop.

Therefore, as shown in FIG. 10, in order to periodically clean the planar antenna 6, the detecting means cleaning means is provided at the end of the developer stirring member 3 for stirring and transporting the developer in the developer accommodating section 4. There is a method of providing a planar antenna cleaning member as a member and cleaning the surface of the planar antenna 6 with the operation of the developer stirring member 3. As the planar antenna cleaning member 36, a sheet member 36b made of, for example, PET (polyethylene terephthalate) is attached to a support member 36a driven by the operation of the developer stirring member 3, and the surface of the planar antenna 6 is A configuration in which cleaning is performed by rubbing the

On the other hand, the developer stirring member 3 in the developer accommodating section 4 is generally driven at a constant rotational speed by being driven by the rotational drive of the electrophotographic photosensitive member, and moves at a constant rotational speed. For example, a rotating plate-shaped sheet metal, a crank-shaped bar, a square bar, or a material obtained by attaching a resin or rubber thereto, is generally rotated around a rotation axis to rotate the developer in the developer storage unit 4. Is stirred, and a developer is supplied to the developing means 10.
The developer stirring member 3 shown in FIG. 10 is configured by attaching a sheet member 3b made of resin to a rotating rod member 3a that is a rotating shaft.

The developer agitating member 3 has a function of loosening the developer in the developer accommodating portion and supplying the developer to the developing means 10 without delay, so that the developer agitating member 3 is located at a position where the inside of the developer accommodating portion 4 can be largely rotated. , Are arranged substantially parallel to the developing roller 2 provided in the developing means 10.

[0013]

However, since the developer agitating member 3 operates at a constant rotational speed, the developer agitating member 3 can be operated without any problem even when the developer accommodating portion 4 has a large amount of developer. The developer agitating member 3 and the support member for the developer stirring member 3 must be configured to have such a strength as to rotate. As a result, the developer container 4 of the process cartridge
And the configuration of the image forming apparatus becomes large, making it difficult to handle.

If the developer stirring member 3 is rotated at a high speed when there is a large amount of developer, the stress applied to the developer is increased and the developer is degraded, so that the image density is lowered and fog is generated on a white background. In some cases, image deterioration such as fraying occurs.

On the other hand, it is conceivable to reduce the strength required for the developer agitating member 3 and components such as the support member by reducing the rotation speed of the developer agitating member 3. When the amount of toner is reduced, the developer may not be readily loosened, or the supply of the developer to the developing unit 10 may not be able to be performed in time, and the image density may be reduced.

Accordingly, an object of the present invention is generally to provide a process cartridge and an electrophotographic image forming apparatus capable of forming a small, high-quality image by changing the stirring speed of the developer according to the amount of the developer in the developer accommodating section. It is to provide.

In particular, an object of the present invention is to increase the size of the structure accompanying the increase in the strength of the developer stirring member, to deteriorate the image due to the deterioration of the developer due to the high speed driving of the developer stirring member, and to reduce the image quality of the developer stirring member. An object of the present invention is to provide a process cartridge and an electrophotographic image forming apparatus which can prevent a decrease in image density due to low-speed driving by making the driving speed of a developer stirring member variable.

In particular, another object of the present invention is to make it possible to form a small and always high-quality image by making the driving speed of the developer stirring member variable, and at the same time, to use the developer amount detecting means. An object of the present invention is to provide a process cartridge and an electrophotographic image forming apparatus which can always perform highly accurate developer amount detection without affecting the amount sequential detection.

[0019]

The above object is achieved by a process cartridge and an electrophotographic image forming apparatus according to the present invention. In summary, a first aspect of the present invention is a process cartridge detachable from an electrophotographic image forming apparatus main body, wherein (a) an electrophotographic photosensitive member, and (b) a process means acting on the electrophotographic photosensitive member; c) a developer accommodating section for accommodating a developer used for developing an electrostatic latent image formed on the electrophotographic photosensitive member, and (d) the process cartridge is mounted on the electrophotographic image forming apparatus main body. In the state, a substantially flat developer amount detecting means provided in the developer accommodating portion for sequentially detecting the amount of the developer in the developer accommodating portion by the electrophotographic image forming apparatus,
(E) provided in the developer accommodating portion, operated by drive transmission from the electrophotographic image forming apparatus main body in a state where the process cartridge is mounted on the electrophotographic image forming apparatus, and A detecting means cleaning member for cleaning the developer amount detecting surface; and (f) provided in the developer accommodating section, wherein the process cartridge is mounted in the electrophotographic image forming apparatus and the electrophotographic image forming apparatus main body includes: A developer agitating member for agitating the developer in the developer accommodating portion by the drive transmission of the developer cartridge, and developing the developer in the developer accommodating portion in a state where the process cartridge is mounted on the main body of the electrophotographic image forming apparatus. In the process cartridge, the stirring speed of the developer stirring member may be changed according to the amount of the developer.

According to one embodiment of the first invention,
The drive transmission of the detecting means cleaning member from the electrophotographic image forming apparatus main body and the drive transmission of the developer stirring member from the electrophotographic image forming apparatus main body are independent, and the detection means cleaning member and the developing device The driving speed of the agent stirring member is independently controlled.

According to a second aspect of the present invention, there is provided an electrophotographic image forming apparatus for detachably attaching a process cartridge and forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; A process unit that acts on a photoconductor, a developer storage unit that stores a developer used to develop an electrostatic latent image formed on the electrophotographic photoconductor, and the process cartridge is a main body of the electrophotographic image forming apparatus. A state in which the electrophotographic image forming apparatus sequentially detects the amount of the developer in the developer accommodating portion, and a substantially planar developer amount detecting means provided in the developer accommodating portion; The process cartridge is provided in the developer accommodating portion, and is activated by drive transmission from the electrophotographic image forming apparatus main body in a state where the process cartridge is mounted on the electrophotographic image forming apparatus. A detecting means cleaning member for cleaning a developer amount detecting surface of the developer amount detecting means; and the electrophotographic apparatus provided in the developer accommodating section, wherein the process cartridge is mounted on the electrophotographic image forming apparatus. Mounting means for removably mounting a process cartridge having a developer agitating member for agitating the developer in the developer accommodating section by drive transmission from the image forming apparatus main body; and (b) statically attaching to the electrophotographic photosensitive member. And an electrostatic latent image forming unit for forming an electrostatic latent image, wherein the process cartridge is mounted on the image forming apparatus main body, and based on an output of the developer amount detecting unit of the process cartridge. The drive speed of the developer stirring member of the process cartridge according to the amount of developer in the developer storage portion of the process cartridge detected by Electrophotographic image forming apparatus characterized by varying the is provided.

According to one embodiment of the second invention,
Means for transmitting drive to the detection means cleaning member and the developer stirring member of the process cartridge are independently provided, and drive speeds of the detection means cleaning member and the developer stirring member are independently controlled.

According to another embodiment of the second invention, the interval at which the output signal of the developer amount detecting means of the process cartridge is read is determined according to the amount of the developer in the developer accommodating portion of the process cartridge. Change.
According to a preferred embodiment, the drive transmission of the process cartridge to the detecting means cleaning member and the developer stirring member is performed by a single driving means, and the driving speed of the detecting means cleaning member and the developer stirring member is controlled. Are controlled together.

According to a preferred embodiment of the first and second aspects of the present invention, the developer amount detecting means is provided at least at a pair of fixed intervals, which is arranged at a position in contact with the developer in the developer accommodating portion. And an electrode pattern having an input electrode and an output electrode having portions juxtaposed.

The process cartridge includes at least one of a charging unit, a developing unit, and a cleaning unit as the process unit, and the electrophotographic photosensitive member. The cartridge is integrated with the electrophotographic image forming apparatus. The process cartridge may be detachable from the main body, or at least the developing means and the electrophotographic photosensitive member may be integrally formed as a cartridge as the process means, and the cartridge may be used as an electrophotographic image forming apparatus. It is designed to be removable from the main body.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a process cartridge and an electrophotographic image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

Embodiment 1 First, an embodiment of an electrophotographic image forming apparatus to which a process cartridge according to the present invention can be mounted will be described with reference to FIG. In this embodiment, the electrophotographic image forming apparatus is an electrophotographic laser beam printer, which forms an image on a recording medium, for example, a recording paper, an OHP sheet, a cloth, or the like by an electrophotographic image forming process. FIG. 1 shows a schematic configuration in a state where the process cartridge C is mounted on the main body 100 of the electrophotographic image forming apparatus.

The electrophotographic image forming apparatus of this embodiment (hereinafter referred to as
It is simply called “image forming apparatus”. ) Is an image carrier.
In the figure, a cylindrical electrophotographic photosensitive member rotatable in the direction of the arrow, that is, an electrophotographic photosensitive drum (hereinafter, referred to as “photosensitive drum”) 1 is provided. An electrostatic latent image is formed by means for forming a latent image. That is,
The surface of the photosensitive drum 1 is uniformly charged by the charging means 7. Next, the surface is scanned and exposed with laser light L corresponding to image information emitted from a laser scanner 11 as an exposure unit, and an electrostatic latent image of target image information is formed on the photosensitive drum 1.

Thereafter, the electrostatic latent image is transferred to the photosensitive drum 1
With the rotation of the developing unit 10, the developing unit 10 reaches a region (developing unit) opposed to the developing unit 10, and the inside of the developer accommodating unit 4 connected to the developing unit 10 by the action of the developing roller 2 as a developer carrying member included in the developing unit 10. Is attached thereto, and is visualized as a so-called toner image. In this example, a magnetic one-component toner was used as the developer.

That is, the developing means 10 includes a developing roller 2 having a fixed magnet 2a therein as a developer carrying member, and an elastic blade 5 serving as a means for regulating the layer thickness of the developer carried on the developing roller 2. With the rotation of the developing roller 2 in the direction of the arrow, the developer in the developer accommodating portion 4 connected to the developing means 10 is carried on the peripheral surface of the developing roller 2 while being charged. Further, the developer is charged and the layer thickness is regulated by the rubbing with the elastic blade 5, and reaches a portion (transfer portion) facing the photosensitive drum 1 with the rotation of the developing roller 2. This is visualized by transitioning to the electrostatic latent image on 1. Normally, a developing bias voltage in which a DC voltage is superimposed on an AC voltage is applied to the developing roller 2.

On the other hand, the recording medium P stored in the paper feed cassette 13 is sent out to a pair of registration rollers 16 by conveyance means such as a paper feed roller 14 and a conveyance guide 15, and is transferred onto the photosensitive drum 1 by the pair of registration rollers 16. And is conveyed to a portion (transfer portion) where the transfer roller 12 serving as a transfer unit and the photosensitive drum 1 are opposed to each other. Then, the toner image on the photosensitive drum 1 is transferred to the recording medium P by the action of the transfer roller 12.

The recording medium P on which the toner image has been transferred in this manner
Is conveyed to the fixing means 13, and the toner image is fixed on the recording medium P by heat and pressure, and then discharged outside the image forming apparatus.

Further, the developer remaining on the photosensitive drum 1 after completion of the transfer is removed by a cleaning means 8 and stored in a waste developer container 9, and the photosensitive drum 1 is repeatedly used for image formation.

In this embodiment, the photosensitive drum 1, a charging means 7 as a process means acting on the photosensitive drum 1, a developing means 10 and a cleaning means 8, and a developer accommodating portion connected to the developing means 10 4. The waste developer container 9 connected to the cleaning means 8 is integrally formed into a cartridge by the frame 19, and the image forming apparatus main body 100
Image forming apparatus main body 1 through mounting means 17 provided in
00 is a removable process cartridge C. Then, the process cartridge C is moved to the image forming apparatus main body 10.
0, the process cartridge C in FIG.
An image is formed on the recording medium P by the above-described electrophotographic image forming process, together with the laser scanner 11 disposed above and the transfer means 12 disposed below.

Next, the inside of the developer accommodating section 4 of the process cartridge C of this embodiment will be described with reference to FIG.

The developer accommodating section 4 is provided with a developer stirring member 3 which rotates in the direction of arrow A. The developer is loosened by the rotation of the developer stirring member 3 and supplied to the developing roller 2. Is done. In this embodiment, the developer stirring member 3 is configured by attaching a sheet member 3b to a rotating rod member 3a that is a rotating shaft. As the sheet member 3b, for example, a sheet formed of PET resin can be used.

In the image forming apparatus of the present embodiment, since the developer in the developer accommodating portion 4 of the process cartridge C is sequentially detected in a state where the process cartridge C is mounted on the main body of the image forming apparatus. A side surface of the developer accommodating portion 4 of the process cartridge C, that is, one side surface along a direction orthogonal to the axis of the developing roller 2 has a flat surface as a developer amount detecting unit. An antenna 6 is provided. Then, the control means 18 provided on the image forming apparatus main body 100 side sequentially detects the remaining amount of the developer in the developer accommodating section 4 based on the output of the flat antenna 6.

As shown in FIG. 3, the planar antenna 6 includes a pair of electrode patterns 20 having portions arranged on the base 24 at predetermined intervals. That is, a conductor pattern 20 such as copper composed of the input side electrode 21 and the output side electrode 22 is formed on the normal printed board 24 by a normal method such as etching or printing, and the protection is performed to protect the electrode pattern 20. A film 25 is formed on the conductive pattern.

Then, a voltage is applied between the electrodes 21 and 22 from a voltage applying means (not shown) provided in the image forming apparatus main body 100 via the input side electrode 21, and the image forming apparatus is output via the output side electrode 22. The control unit 18 provided in the main body 100 detects the capacitance of the electrode pattern 20.

The distance between the input side electrode 21 and the output side electrode 22 of the electrode pattern 20 is determined as appropriate.
In this embodiment, the interval between the electrodes 21 and 22 is reduced to about several tens of μm. In this embodiment, when a voltage of 200 Vpp and 2000 Hz is applied as an AC bias between the electrodes 21 and 22, when the developer is not in contact with the planar antenna 6, the developer is in contact with the entire surface of the planar antenna 6 at 20 pF. Sometimes different capacitances of 60 pF are observed.

Therefore, when the planar antenna 6 is arranged in the side surface of the developer accommodating portion 4, that is, in the direction in which the contact area with the developer varies as the amount of the developer decreases in the developer accommodating portion 4. The contact area between the developer and the planar antenna 6 decreases as the amount of the developer in the developer accommodating section 4 decreases, and the capacitance between the electrodes 21 and 22 of the planar antenna 6 is observed, thereby sequentially storing the developer. The developer amount in the section 4 can be detected.

As described above, when the developing operation is actually performed, even if the developer in the developer accommodating section 4 gradually decreases, the developer slightly adheres to the flat antenna 6 and remains there. The result of detection of the amount of developer by the antenna 6 varies. Therefore, as will be described in detail later, in order to remove the developer adhered to the surface of the planar antenna 6, the planar antenna cleaning member 36 serving as a detecting means cleaning member is removed.
Is provided.

As will be described later, according to the present embodiment, the planar antenna cleaning member 36 rotates coaxially with the rotary rod member 3a of the developer stirring member 3, and cleans the surface of the planar antenna 6 by stroking. Configuration. Therefore, as shown in FIG. 3, a hole 23 is provided at a substantially central portion of the planar antenna 6, the developer stirring member 3 is supported through the hole 23, and a planar antenna cleaning member 36 coaxial with the developer agitating member 3 is provided. The configuration is such that the entire area can be cleaned.

Further, since the output of the planar antenna 6 fluctuates in a periodic surface cleaning cycle due to the rotation of the planar antenna cleaning member 36, an average value of the output of the planar antenna 6 or a minimum value is obtained in accordance with the cycle. Processing such as selection is performed by the control unit 18 provided in the image forming apparatus main body 100.

As described above, since the rotating torque of the developer stirring member 3 greatly varies depending on the amount of the developer, even when the maximum amount of the developer at which the rotating torque is maximized is in the developer accommodating portion. It must be constructed so that it can rotate without hindrance. Further, when the rotation speed is set to be low so that the rotation torque of the developer stirring member 3 becomes small, when the amount of the developer in the developer accommodating portion 4 becomes small, the consumption of the developer by the developing roller 2 is reduced. In some cases, the supply of the developer to the developing roller 2 is delayed, and an image having an appropriate density cannot be formed.

Therefore, the rotation speed of the developer stirring member 3 is
By changing according to the amount of the developer in the developer accommodating section 4, that is, when the amount of the developer is large, the rotation speed is reduced to reduce the rotation torque, and when the amount of the developer is small, the rotation is reduced. It is conceivable to increase the speed so that the developer is appropriately supplied to the developing roller 2.

However, conventionally, in order to periodically clean the surface of the planar antenna 6, for example, as shown in FIG. In addition, a flat antenna cleaning member 36 as a detecting means cleaning member is provided, and the surface of the flat antenna 6 is cleaned with the rotation of the developer stirring member 3.

As described above, in the conventional configuration in which the planar antenna cleaning member 36 is provided at the longitudinal end portion of the developer stirring section 3 and the surface of the planar antenna 6 is cleaned with the rotation of the developer stirring section 3, If the rotation speed of the stirring member 3 is simply changed in accordance with the amount of the developer, the cleaning cycle of the planar antenna 6 also changes, so that an error occurs in the determination of the amount of the developer based on the output of the planar antenna 6.

Therefore, according to the present invention, in this embodiment,
The amount of operation (rotational speed in the present embodiment) of the developer stirring member 3 can be changed according to the amount of developer in the developer container 4,
At the same time, the configuration is such that the amount of the developer in the developer accommodating section 4 can be accurately measured.

This will be described more specifically with reference to FIG. FIG. 4 shows a schematic configuration of the vicinity of the photosensitive drum 1, the developing roller 2, the developer stirring member 3, and the planar antenna cleaning member 36 of the process cartridge C of the present embodiment, and the driving unit thereof as viewed from above.

As shown in FIG. 4, in this embodiment, a photosensitive member driving gear 31 is provided at the longitudinal end of the photosensitive drum 1. The photoreceptor drum 1 rotates upon receiving a drive transmission from a driving unit (not shown) included in the image forming apparatus main body 100.
The developing roller 2 has a developing roller driving gear 32 meshed with the photosensitive member driving gear 31 at a longitudinal end thereof. When the photosensitive drum 1 rotates, the developing roller 2 also rotates. Further, the developing roller drive gear 32 is connected via an idler gear 33 to a cleaning member drive gear 34 that rotationally drives the planar antenna cleaning member 36.

The cleaning member driving gear 34 is
Is formed at a longitudinal end portion of a support member 36a which is a rotation axis of the planar antenna cleaning member 36 and penetrates the position of the hole 23 at the approximate center. The support member 36a is rotationally driven by the drive transmitted via the idler gear 33, and the support member 36a is rotated.
The surface of the planar antenna 6 is stroked and cleaned by the sheet member 36b adhered to a. The sheet member 36b of the planar antenna cleaning member 36 is, for example, P
A sheet formed of ET (polyethylene terephthalate) can be used.

This series of gear trains (gears 31, 32, 3
3, 34) rotate at a constant speed when the photoconductor drive gear 31 receives drive transmission.

On the other hand, the developer stirring member 3 is formed coaxially with the planar antenna cleaning member 36, and is configured to be rotatable independently by another drive. That is, as shown in FIG.
The rotating rod member 3a, which is the rotation axis of the developer stirring member 3, is supported by the support member 36a, which is the rotation axis of the planar antenna cleaning member 36.
And a drive receiving member 35 provided at a longitudinal end thereof is connected to a driving means (not shown) provided in the image forming apparatus main body 100, and the developer stirring member 3 is provided.
Can be rotationally driven independently of the driving of the gear trains 31, 32, 33, 34 described above.

Therefore, the developer stirring member 3 can be rotated at an optimum stirring speed in accordance with the amount of the developer in the developer accommodating section 4 detected based on the output of the planar antenna 6, and Since the antenna cleaning member 36 always rotates at a constant speed, that is, cleans the surface of the planar antenna 6 at a constant cleaning cycle, the output of the planar antenna 6 that fluctuates at the cleaning cycle is equal to the rotation speed of the developer stirring member 3. It is not affected by change.

The rotation speed of the developer stirring member depends on the amount of the developer in the developer accommodating section 4, and the strength of the developer stirring member 3, the size of the developer accommodating section 4 and the size of the image forming apparatus main body 100. Alternatively, it is appropriately determined in consideration of the image forming speed or the like. Further, the rotation speed of the developer stirring member 3 may be changed stepwise or continuously according to the amount of the developer detected based on the output of the planar antenna 6.

In this embodiment, the driving of the developer stirring member 3 and the planar antenna cleaning member 36 has been described as being driven by rotation. However, the present invention is not limited to this. The effect of the present invention can be similarly obtained by making the driving speed of the developer stirring member 3 variable by independently driving the reciprocating motion and the like.

As described above, according to the embodiment of the present invention, since the developer stirring member 3 and the planar antenna cleaning member 36 are independently driven to rotate, the developer amount detection based on the output of the planar antenna 6 can be performed. The rotation speed of the developer stirring member 3 can be changed according to the amount of the developer in the developer accommodating portion 4 without affecting the rotation speed.

Embodiment 2 The basic structure of the electrophotographic image forming apparatus of this embodiment and the process cartridge mounted on the main body of the electrophotographic image forming apparatus are the same as those of Embodiment 1, so the same structure The same reference numerals are given to members having functions and functions, and detailed description thereof is omitted.

Also in this embodiment, according to the present invention, the developer stirring member 3 according to the amount of the developer in the developer accommodating container 4 is used.
Is configured to be changeable, and at the same time, the amount of the developer in the developer accommodating section 4 can be accurately measured.

The following is a more specific description. FIG. 5 shows a schematic configuration of the vicinity of the photosensitive drum 1, the developing roller 2, the developer stirring member 3, and the planar antenna cleaning member 36 of the process cartridge C of the present embodiment, and the drive unit thereof as viewed from above.

In this embodiment, the planar antenna cleaning member 36 is used.
Is configured to rotate together with the developer stirring member 3,
The rotation speed of the planar antenna cleaning member 36 also changes according to the amount of the developer in the developer accommodating section 4. That is, as shown in FIG. 5, the developer stirring member 3 and the planar antenna cleaning member 36 are formed coaxially, and the rotating rod member 3a and the supporting member 36a, which are the respective rotating shafts, are fixed, and the planar antenna 6 is fixed. A single rotating shaft that penetrates the hole 23 in the approximate center is formed. When the drive receiving member 35 provided at the longitudinal end of the rotation shaft is driven by a driving unit (not shown) provided in the image forming apparatus main body 100, the developer stirring member 3 and the planar antenna cleaning member are driven. 36 is driven to rotate.

As described above, since the output of the planar antenna 6 fluctuates in the cleaning cycle, the planar antenna cleaning member 3
If the driving speed of the developer stirring member 3 is simply changed by driving the developer stirring member 3 together with the developer stirring member 3, the cleaning cycle of the planar antenna 6 also changes at the same time, and the developer amount cannot be detected accurately.

Therefore, in this embodiment, the sampling period of the output signal of the planar antenna 6 is changed according to the rotation speed of the planar antenna cleaning member 36, and the amount of the developer in the developer accommodating section 4 is accurately detected. The configuration is as follows.

FIG. 6 shows the time variation of the output of the planar antenna 6 which changes according to the rotation speed of the planar antenna cleaning member 36. According to the present embodiment, the developer stirring member 3 rotates at 5 rpm (1 rotation in 12 seconds) when the amount of the developer in the developer accommodating section 4 is large, and 1 when the amount of the developer is low.
Rotate at 0 rpm (1 rotation in 6 seconds). In addition, the rotation of the planar antenna cleaning member 36 causes the output of the planar antenna 6 to fluctuate in a width of about 1 pF, and the period of the fluctuation is long when the rotation speed of the planar antenna cleaning member 36 is low, and short when the rotation speed is low.

Therefore, in this embodiment, the output signal of the planar antenna 6 is sampled at the following timing.
FIG. 7 shows a timing chart for sampling the output signal of the planar antenna 6 when the signal shown in FIG.

That is, the amount of the developer is large and the rotation speed of the developer stirring member 3 is 5
Sampling timing (II) when rpm is slow
The output signal of the planar antenna 6 is read according to (1 MHz). When the developer amount is small and the rotation speed of the developer stirring member 3 is as fast as 10 rpm, the output signal of the planar antenna 6 is read according to the sampling timing (I) (2 MHz). When adding processing such as averaging to the output value of the planar antenna 6 read by the control unit 18,
The process is always performed with the same number of samples.

By doing so, the rotation speed of the developer stirring means 3 is changed according to the amount of the developer in the developer accommodating section 4,
Even if the rotational speed of the planar antenna cleaning member 36 changes accordingly, the output of the planar antenna 6 in the same phase of the cleaning cycle is sampled for each rotational speed, and processing such as averaging is performed for the same number of samples. Is performed to detect the amount of developer, so that the variation in the result of detection of the amount of developer due to a change in the cleaning cycle can be minimized.

That is, according to this embodiment, the planar antenna 6
The developer agitating member 3 is rotated at an optimal agitation speed in accordance with the amount of the developer in the developer accommodating portion 4 detected based on the output of the above, and at the same time, the timing of reading the output of the planar antenna 6 is changed. The effect of the rotation speed of the developer stirring member 3, that is, the cleaning cycle, which changes according to the rotation speed of the planar antenna cleaning member 36, on the output of the planar antenna 6 is the same regardless of the amount of the developer in the developer storage unit 4. And it is possible to detect the amount of the developer having a small variation.

In this embodiment, the drive of the developer stirring member 3 and the cleaning of the planar antenna cleaning member 36 is described as a rotational drive. Is also possible.

The rotation speed of the developer stirring member depends on the amount of the developer in the developer accommodating section 4 and the strength of the developer stirring member 3 and the size of the developer accommodating section 4 and the image forming apparatus main body 100. Alternatively, it is appropriately determined in consideration of the image forming speed or the like. Further, the rotation speed of the developer stirring member 3 may be changed stepwise or continuously according to the amount of the developer detected based on the output of the planar antenna 6.

As described above, according to the second embodiment of the present invention, in the simple configuration in which the planar antenna cleaning member 36 and the developer stirring member 3 are simultaneously rotated, the timing of sampling the output of the planar antenna 6 is adjusted. The developer stirring member 3 is changed according to the amount of the developer in the developer accommodating portion 4 without changing the amount of the developer based on the output of the planar antenna 6 by changing the rotation according to the rotation speed of the stirring member 3. Can be made variable.

[0073]

As described above, the process cartridge of the present invention comprises an electrophotographic photosensitive member; process means acting on the electrophotographic photosensitive member; and developing an electrostatic latent image formed on the electrophotographic photosensitive member. And a developer accommodating section for accommodating a developer used for the purpose of detecting the amount of the developer in the developer accommodating section by the electrophotographic image forming apparatus in a state where the process cartridge is mounted on the main body of the electrophotographic image forming apparatus. A substantially flat developer amount detecting means provided in the developer accommodating portion; and a process cartridge provided in the developer accommodating portion, wherein the process cartridge is mounted on the electrophotographic image forming apparatus, and A detecting means cleaning member which operates by the drive transmission of the developer and cleans the developer amount detecting surface of the developer amount detecting means; provided in the developer accommodating portion, and the process cartridge is an electrophotographic printer. Have; and a developer stirring member for stirring the developer in the developer accommodating portion by a drive transmission from the electrophotographic image forming apparatus main body in a state of being mounted to an image forming apparatus
With the process cartridge attached to the electrophotographic image forming apparatus main body, according to the amount of developer in the developer accommodating portion,
The stirring speed of the developer stirring member is variable, and the image forming apparatus of the present invention is capable of mounting the process cartridge of the present invention, and the process cartridge is mounted in a state where the process cartridge is mounted on the image forming apparatus main body. The driving speed of the developer agitating member of the process cartridge is changed according to the amount of developer in the developer accommodating portion of the process cartridge detected based on the output of the developer amount detecting means. The developer stirring member can be driven at an optimum stirring speed in accordance with the amount of developer in the unit, and the structure of the developer stirring member is increased in size with increasing strength,
It is possible to prevent the image deterioration due to the deterioration of the developer due to the high speed driving of the developer stirring member, and the decrease in the image density due to the low speed driving of the developer stirring member.

Also, according to the present invention, the drive speed of the developer stirring member is made variable, and at the same time, it does not affect the sequential detection of the developer amount by the developer amount detecting means, so that the developer amount can always be detected with high accuracy. It is possible.

Therefore, according to the present invention, it is possible to provide a process cartridge and an electrophotographic image forming apparatus capable of forming a high-quality image with a small size and maintaining high detection accuracy of the amount of the simultaneous developer.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of an electrophotographic image forming apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram showing one embodiment of a process cartridge according to the present invention.

FIG. 3 is a diagram illustrating a developer amount detecting unit (a planar antenna) provided in a developer accommodating portion of the process cartridge according to the present invention.
FIG.

FIG. 4 is a view for explaining an embodiment of a drive configuration of a developer stirring member and a planar antenna cleaning member of the process cartridge according to the present invention.

FIG. 5 is a view for explaining another embodiment of the drive configuration of the developer stirring member and the planar antenna cleaning member of the process cartridge according to the present invention.

FIG. 6 is a graph showing the time variation of the output signal of the planar antenna according to the present invention.

FIG. 7 is a timing chart showing a timing of sampling an output signal of a planar antenna in another embodiment of the electrophotographic image forming apparatus according to the present invention.

FIG. 8 is a schematic configuration diagram illustrating an example of a conventional electrophotographic image forming apparatus.

FIG. 9 is a diagram illustrating an example of a planar antenna provided in a developer accommodating section.

FIG. 10 is a view for explaining a conventional planar antenna cleaning member which rotates together with a developer stirring member.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor drum (electrophotographic photoconductor) 2 developing roller (developer carrier) 3 developer stirring member 4 developer storage unit 6 planar antenna (developer amount detecting means) 7 charging means 8 cleaning means 9 waste developer container DESCRIPTION OF SYMBOLS 11 Laser scanner exposure means 17 Mounting means 18 Control means 20 Electrode pattern 36 Planar antenna cleaning member (detection means cleaning member)

Claims (12)

[Claims] 1. A process cartridge detachable from a main body of an electrophotographic image forming apparatus, comprising: (a) an electrophotographic photosensitive member; (b) process means acting on the electrophotographic photosensitive member; and (c) the electrophotographic photosensitive member. A developer accommodating section for accommodating a developer used for developing an electrostatic latent image formed on a body; and (d) the developer in a state where the process cartridge is mounted on the electrophotographic image forming apparatus main body. A substantially planar developer amount detecting means provided in the developer accommodating portion for sequentially detecting the amount of the developer in the accommodating portion by the electrophotographic image forming apparatus; and (e) in the developer accommodating portion. A developer cartridge provided in the electrophotographic image forming apparatus, and operated by drive transmission from the electrophotographic image forming apparatus main body when the process cartridge is mounted on the electrophotographic image forming apparatus; (F) drive transmission from the main body of the electrophotographic image forming apparatus provided in the developer accommodating section, wherein the process cartridge is mounted in the electrophotographic image forming apparatus; A developer agitating member for agitating the developer in the developer accommodating section, and wherein the amount of the developer in the developer accommodating section is reduced in a state where the process cartridge is attached to the electrophotographic image forming apparatus main body. A process cartridge, wherein the stirring speed of the developer stirring member is variable in response. 2. The drive transmission of the detecting means cleaning member from the electrophotographic image forming apparatus main body and the drive transmission of the developer stirring member from the electrophotographic image forming apparatus main body are independent of each other. 2. The process cartridge according to claim 1, wherein the driving speeds of the cleaning member and the developer stirring member are independently controlled. 3. The input-side electrode and the output-side electrode having at least a pair of juxtaposed portions arranged at a fixed interval, which are arranged at a position in contact with the developer in the developer accommodating portion. The process cartridge according to claim 1, further comprising an electrode pattern having: 4. The process cartridge, wherein at least one of a charging unit, a developing unit, and a cleaning unit as the process unit and the electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is formed into an electrophotographic image forming apparatus. 4. The process cartridge according to claim 1, wherein the process cartridge is detachable from a main body. 5. The process cartridge according to claim 1, wherein at least the developing means and the electrophotographic photosensitive member are integrally formed as a cartridge as the process means, and the cartridge is detachably mountable to an electrophotographic image forming apparatus main body. The process cartridge according to claim 1, 2 or 3. 6. An electrophotographic image forming apparatus for detachably attaching a process cartridge and forming an image on a recording medium, comprising: (a) an electrophotographic photosensitive member; and a process means acting on the electrophotographic photosensitive member. A developer accommodating section for accommodating a developer used for developing an electrostatic latent image formed on the electrophotographic photoreceptor; and, in a state where the process cartridge is attached to the electrophotographic image forming apparatus main body, A substantially planar developer amount detecting means provided in the developer accommodating portion for sequentially detecting the amount of the developer in the developer accommodating portion by the electrophotographic image forming apparatus; and provided in the developer accommodating portion. The process cartridge is mounted on the electrophotographic image forming apparatus, and is operated by drive transmission from the electrophotographic image forming apparatus main body, thereby detecting the developer amount. A detecting member cleaning member for cleaning the developer amount detecting surface of the electrophotographic image forming apparatus, wherein the detecting means is provided in the developer accommodating section, and the process cartridge is mounted on the electrophotographic image forming apparatus and driven from the electrophotographic image forming apparatus main body. Mounting means for removably mounting a process cartridge having a developer stirring member for stirring the developer in the developer storage section by transmission; and (b) forming an electrostatic latent image on the electrophotographic photosensitive member. And an electrostatic latent image forming unit, wherein the process cartridge is mounted on the image forming apparatus main body, and the process cartridge is detected based on an output of the developer amount detecting unit of the process cartridge. It is characterized in that the driving speed of the developer stirring member of the process cartridge is changed according to the amount of the developer in the developer accommodating section. An electrophotographic image forming apparatus. 7. A process unit for independently transmitting drive to the detection means cleaning member and the developer stirring member of the process cartridge, wherein drive speeds of the detection means cleaning member and the developer stirring member are controlled independently. 7. The electrophotographic image forming apparatus according to claim 6, wherein the control is performed by controlling the image forming apparatus. 8. The process cartridge according to claim 6, wherein an interval at which an output signal of said developer amount detecting means of said process cartridge is read is changed in accordance with a developer amount in said developer accommodating portion of said process cartridge. Electrophotographic image forming apparatus. 9. The drive transmission of the process cartridge to the detecting means cleaning member and the developer stirring member is performed by a single driving means, and both the driving speeds of the detecting means cleaning member and the developer stirring member are controlled. The electrophotographic image forming apparatus according to claim 8, wherein 10. An input-side electrode and an output-side electrode having at least a pair of juxtaposed portions arranged at a fixed interval, which are arranged at a position in contact with the developer in the developer accommodating portion. The electrophotographic image forming apparatus according to any one of claims 6 to 9, further comprising an electrode pattern having: 11. The process cartridge, wherein at least one of a charging unit, a developing unit, and a cleaning unit as the process unit and the electrophotographic photosensitive member are integrally formed into a cartridge, and the cartridge is formed into an electrophotographic image forming apparatus. The electrophotographic image forming apparatus according to any one of claims 6 to 10, wherein the electrophotographic image forming apparatus is detachable from a main body. 12. The process cartridge according to claim 1, wherein at least the developing means and the electrophotographic photosensitive member are integrally formed as a cartridge as the process means, and the cartridge is detachably mountable to an electrophotographic image forming apparatus main body. The electrophotographic image forming apparatus according to claim 6.