JP2013145317A - Developing unit, process cartridge, image forming apparatus, and developer supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing unit capable of suppressing a reduction in image quality after developer is supplied, a process cartridge, an image forming apparatus, and a developer supply method.SOLUTION: When a developing unit 23 is made to have an attitude of being turned upside down in a vertical direction with an attitude when being attached to an image forming apparatus body as a reference (reverse attitude), while a toner cartridge as a developer container is supplied at once with a new toner T1, a toner supply port 89 is arranged so that the toner supply port 89 as a developer supply port is disposed above a draft surface in a vertical direction of a toner in a hopper unit 86 as a developer storage unit.

Description

  The present invention relates to a developing unit, a process cartridge, an image forming apparatus, and a developer supply method.

  Conventionally, when toner as a developer in the developing unit is low, development with a batch toner replenishment method in which all new toner is put into the developing unit at once from a toner container as a developer storage container containing new toner. Units are known (for example, Patent Documents 1 and 2).

  Specifically, the developing unit serves as a developer container that extends vertically above the developer supply member that pumps up the developer accumulated on the lower side in the vertical direction of the developing unit and supplies the developer to the developer carrier, and stores toner. The toner hopper is arranged. A toner supply port as a developer supply port is provided on the upper surface of the toner hopper, and a toner container is set in the toner supply port. Then, by peeling off the seal member attached to the lower surface of the toner container, the toner in the toner container falls by its own weight from the toner supply port, and the toner is supplied to the developing unit all at once.

  In the development unit of the collective toner replenishment system as described above, the toner in the development unit deteriorates due to agitation and the like due to use over time, and differs from the initial charging characteristics. For this reason, for example, the toner deterioration state in the developing unit is grasped using the rotation speed of the photosensitive member as the latent image carrier, and the developing condition (for example, developing bias) corresponding to the toner deterioration state is changed. Control is in progress. When new toner is supplied all at once in the developing unit, the rotational speed of the photosensitive member is reset and the developing conditions corresponding to the new toner are switched.

  However, in the conventional developing unit, a toner replenishing port is provided on the upper surface of the toner hopper, and new toner is replenished from the top of the developing unit. Therefore, new toner is deposited on the old toner remaining in the developing unit. As a result, the lower side of the developing unit is occupied by deteriorated old toner. Therefore, immediately after the batch toner replenishment, the old toner is supplied to the developer carrying member by the developer supply member and used for old toner development. As a result, if the rotation speed of the photosensitive member is reset after batch toner supply and the developing conditions are changed to correspond to new toner, there is a problem that the image quality immediately after the batch toner supply is deteriorated.

  In order to solve the above problem, it is conceivable to perform development under conditions corresponding to old toner until image formation is performed a predetermined number of times after batch toner replenishment. However, the period from when the old toner is used to when it is switched to a new toner varies, and it may be switched to a new toner at an earlier stage than the predetermined number of times, or may be switched to a new toner at a stage later than the predetermined number of times. End up. If the toner is switched to a new toner at a stage earlier than the predetermined number of times, the image quality is deteriorated because the development is performed under the development conditions corresponding to the old toner even though the new toner is used for development. . In addition, if the toner is switched to a new toner at a stage later than the predetermined number of times, the image quality deteriorates because the development is performed under the development conditions corresponding to the new toner even though the old toner is used as the developer. Resulting in. Therefore, even if it is performed under the development conditions corresponding to the old toner until the image formation is performed a predetermined number of times after the collective toner replenishment, the deterioration of the image quality cannot be sufficiently suppressed.

  SUMMARY An advantage of some aspects of the invention is that it provides a developing unit, a process cartridge, an image forming apparatus, and a developer replenishing method capable of suppressing deterioration in image quality after replenishing a developer. That is.

  In order to achieve the above object, the invention of claim 1, the developer is carried on the surface and moved, and developed into a latent image on the surface of the latent image carrier in a development area facing the latent image carrier. A developer carrying member for supplying and developing the developer, a developer containing portion for containing the developer, and a developer supply member that pumps up the developer accumulated in the lower portion of the developer containing portion and supplies the developer to the developer carrying member. And a developer replenishing port for replenishing a new developer in a developer storage container containing a new developer to the developer accommodating portion, the developing unit is an image forming apparatus main body. The developer unit in a state in which new developer in the developer container is replenished in a batch is turned upside down with respect to the posture when the image forming apparatus main body is mounted. The developer replenishing port is Serial so as to be vertically above the draft plane of the developer in the developer accommodating portion, and is characterized in that arranged above the developer supply opening.

  According to the present invention, when the developing unit after the replenishment of new developer is brought into a posture (hereinafter referred to as a reversing posture) that is vertically inverted with respect to the posture when the image forming apparatus main body is mounted, Since the developer supply port is vertically above the draft surface of the developer in the developer accommodating portion, the developer can be replenished to the developer accommodating portion as follows. That is, it is possible to replenish a new developer from the developer replenishing port with the developing unit in the inverted posture. By setting the developing unit to the above inverted posture, the deteriorated old toner remaining in the lower portion of the developing unit falls by its own weight onto a portion that becomes the lower surface of the developer accommodating portion when in the above inverted posture. When a new developer is replenished from the developer replenishing port to the developer accommodating portion, the new developer is deposited on the old developer that has accumulated at the lower surface of the developer accommodating portion in the above-described reverse posture. After the new developer is replenished, when the developing unit is returned to the posture when mounted on the image forming apparatus, the lower side of the developing unit can be made a new developer. As a result, the new developer is pumped up by the developer supply member and supplied to the developer carrier, and the new developer is used for development. Therefore, the latent image on the latent image carrier can be developed satisfactorily by setting the developing condition after supplying the new developer to the developing condition corresponding to the new developer. Therefore, it is possible to suppress a decrease in image quality after supplying a new developer.

1 is a schematic configuration diagram of a printer according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram of a process unit in the printer. The figure explaining the conventional toner replenishment. FIG. 3 is a schematic configuration diagram illustrating a conventional developing unit after toner supply. FIG. 6 is a diagram illustrating toner replenishment using the developing unit 23 of the present embodiment. FIG. 10 is a schematic configuration diagram of a process unit including a developing unit according to a first modification. FIG. 4 is a schematic diagram illustrating a path for conveying waste toner removed by a cleaning device. FIG. 3 is a schematic perspective view showing a state where a waste toner collection container is removed from a developing unit. FIG. 3 is a schematic perspective view of a waste toner collection container. FIG. 3 is a schematic configuration diagram illustrating a waste toner conveyance path. FIG. 6 is a diagram illustrating setting of a waste toner collection container to a developing unit. FIG. 10 is a schematic diagram when the developing unit of Modification 1 is installed on a table in a reverse posture. FIG. 9 is a schematic diagram illustrating a state where new toner is supplied to the developing unit according to the first modification. FIG. 10 is a schematic perspective view of a toner cartridge in a developing unit according to Modification 2. FIG. 10 is a diagram for explaining toner supply in a second modification.

Hereinafter, as an image forming apparatus to which the present invention is applied, an embodiment of an electrophotographic printer (hereinafter simply referred to as “printer”) will be described.
First, a basic configuration of the printer according to the present embodiment will be described.
FIG. 1 is a schematic configuration diagram illustrating a printer according to the present embodiment. In this figure, the printer includes four process units 26K, C, M, and Y for forming toner images of black, cyan, magenta, and yellow (hereinafter referred to as K, C, M, and Y). Yes. These use different colors of K, C, M, and Y toners as image forming substances, but otherwise have the same configuration and are replaced when the lifetime is reached. Taking a process unit 26K for forming a K toner image as an example, as shown in FIG. 2, a drum-shaped photosensitive member 24K as a latent image carrier, a drum cleaning device 83K, a charge eliminating device (not shown), a charging device. A photosensitive unit 10K that holds 25K and a developing unit 23K are provided. The process unit 26K as an image forming unit is detachable from the printer main body, so that consumable parts can be replaced at a time.

  The charging device 25K uniformly charges the surface of the photoreceptor 24K that is driven to rotate clockwise in the drawing by a driving unit (not shown). The surface of the uniformly charged photoreceptor 24K is exposed and scanned by the laser beam L to carry an electrostatic latent image for K. The electrostatic latent image for K is developed into a K toner image by a developing unit 23K using K toner (not shown). Then, intermediate transfer is performed on an intermediate transfer belt 22 described later. The drum cleaning device 83K removes transfer residual toner adhering to the surface of the photoconductor 24K after the intermediate transfer process. Further, the static eliminator neutralizes residual charges on the photoreceptor 24K after cleaning. By this charge removal, the surface of the photoreceptor 24K is initialized and prepared for the next image formation. Similarly, in the other color process units (26C, M, Y), (C, M, Y) toner images are formed on the photoreceptors (24C, M, Y), and the intermediate transfer belt 22 described later is formed. Intermediate transfer. The cylindrical drum portion of the photoconductor 24K is obtained by coating an organic photosensitive layer on the front surface of a hollow aluminum tube. A flange having a drum shaft is attached to each end of the drum portion in the axial direction to constitute a photosensitive member 24K.

  The developing unit 23K includes a vertically long hopper portion 86K that stores K toner as a developer (not shown), and a developing portion 87K. In the hopper 86K as the developer accommodating portion, an agitator 88K that is rotated by a driving unit (not shown), and a toner supply roller 80K as a developer supplying member that is rotated by a driving unit (not shown) vertically below the agitator 88K. Etc. are arranged. The K toner in the hopper 86K moves toward the toner supply roller 80K by its own weight while being agitated by the rotational drive of the agitator 88K. The toner supply roller 80K has a metal cored bar and a roller portion made of foamed resin or the like coated on the surface of the metal core roller. K toner accumulated on the lower side in the hopper portion 86K is removed from the surface of the roller portion. Rotate while adhering to.

  In the developing portion 87K of the developing unit 23K, a developing roller 81K that rotates while contacting the photoreceptor 24K and the toner supply roller 80K, and a thinning blade 82K that contacts the tip of the developing roller 81K are disposed. Yes. The K toner adhered to the toner supply roller 80K in the hopper 86K is supplied to the surface of the development roller 81K at the contact portion between the development roller 81K and the toner supply roller 80K. When the supplied K toner passes through the contact position between the roller and the thinning blade 82K as the developing roller 81K rotates, the layer thickness on the roller surface is regulated. Then, the K toner whose layer thickness has been regulated adheres to the electrostatic latent image for K on the surface of the photosensitive member 24K in the developing region where the developing roller 81K and the photosensitive member 24K are in contact with each other. By this adhesion, the electrostatic latent image for K is developed into a K toner image.

  The K process unit 26K has been described with reference to FIG. 2, but the C, M, and Y process units 26C, M, and Y also perform C, M on the surfaces of the photoreceptors 24C, M, and Y by a similar process. , Y toner image is formed.

  In FIG. 1 described above, an optical writing unit 27 is disposed above the process units 26K, C, M, and Y in the vertical direction. The optical writing unit 27 as a latent image writing device irradiates the photoconductors 24K, C, M, and Y in the process units 26K, C, M, and Y with the laser light L emitted from the laser diode based on the image information. Scan. By this optical scanning, electrostatic latent images for K, C, M, and Y are formed on the photoreceptors 24K, C, M, and Y. In this configuration, the optical writing unit 27 and the process units 26K, C, M, and Y provide K, C, M, and Y as visible images of different colors on the three or more latent image carriers. It functions as an image forming means for forming a toner image.

  The optical writing unit 27 is a photoconductor through a plurality of optical lenses and mirrors while polarizing laser light (L) emitted from a light source in a main scanning direction by a polygon mirror that is rotationally driven by a polygon motor (not shown). Is irradiated. You may employ | adopt what performs optical writing by the LED light emitted from several LED of the LED array.

  Below the process units 26K, C, M, and Y, a transfer unit 75 is disposed as a belt device that moves the endless intermediate transfer belt 22 endlessly in the counterclockwise direction while stretching. Yes. In addition to the intermediate transfer belt 22, the transfer unit 75 includes a driving roller 76, a tension roller 20, four primary transfer rollers 74K, C, M, and Y, a secondary transfer roller 21, a belt cleaning device 71, and a cleaning backup roller 72. Etc.

  The intermediate transfer belt 22, which is a belt member and a transfer belt, is driven by a driving roller 76, a tension roller 20, a cleaning backup roller 72, and four primary transfer rollers 74 K, C, M, and Y disposed inside the loop. It is stretched. Then, it is moved endlessly in the same direction by the rotational force of the driving roller 76 that is driven to rotate counterclockwise in the drawing by a driving means (not shown).

  The four primary transfer rollers 74K, C, M, and Y sandwich the intermediate transfer belt 22 that is moved endlessly in this manner with the photoreceptors 24K, C, M, and Y. By this sandwiching, primary transfer nips for K, C, M, and Y where the front surface of the intermediate transfer belt 22 and the photoreceptors 24K, C, M, and Y abut are formed.

  A primary transfer bias is applied to the primary transfer rollers 74K, C, M, and Y by a transfer bias power source (not shown), whereby electrostatic latent images on the photoconductors 24K, C, M, and Y, A transfer electric field is formed between the primary transfer rollers 74K, C, M, and Y. Instead of the primary transfer rollers 74K, C, M, and Y, a transfer charger, a transfer brush, or the like may be employed.

  When the Y toner formed on the surface of the photosensitive member 24Y of the Y process unit 26Y enters the above-described primary transfer nip for Y as the photosensitive member 24Y rotates, the photosensitive member 24Y is exposed to light due to the transfer electric field and nip pressure. Primary transfer is performed from above the body 24Y onto the intermediate transfer belt 22. The intermediate transfer belt 22 on which the Y toner image is primarily transferred in this way passes over the primary transfer nips for M, C, and K along with the endless movement thereof, and then on the photoreceptors 24M, C, and K. The M, C, and K toner images are primarily transferred onto the Y toner image in a superimposed manner. A four-color toner image is formed on the intermediate transfer belt 22 by this superimposing primary transfer.

  The secondary transfer roller 21 of the transfer unit 75 is arranged outside the loop of the intermediate transfer belt 22 and sandwiches the intermediate transfer belt 22 between the tension roller 20 inside the loop. By this sandwiching, a secondary transfer nip where the front surface of the intermediate transfer belt 22 and the secondary transfer roller 21 abut is formed. A secondary transfer bias is applied to the secondary transfer roller 21 by a transfer bias power source (not shown). By this application, a secondary transfer electric field is formed between the secondary transfer roller 21 and the tension roller 20 connected to the ground.

  Below the transfer unit 75 in the vertical direction, a paper feed cassette 41 that stores a plurality of recording papers P in a bundle of sheets is slidably attached to the printer housing. In the paper feed cassette 41, a paper feed roller 42 is brought into contact with the top recording paper P of the paper bundle, and the recording paper is rotated by rotating it in a counterclockwise direction in the drawing at a predetermined timing. P is sent out toward the paper feed path.

  Near the end of the paper feed path, a pair of registration rollers including registration rollers 43 and 44 is provided. The registration roller pair stops the rotation of both rollers as soon as the recording paper P as a recording member fed from the paper feed cassette 41 is sandwiched between the rollers. Then, rotation driving is restarted at a timing at which the sandwiched recording paper P can be synchronized with the four-color toner image on the intermediate transfer belt 22 in the above-described secondary transfer nip, and the recording paper P is directed to the secondary transfer nip. Send it out.

  The four-color toner image on the intermediate transfer belt 22 brought into close contact with the recording paper P at the secondary transfer nip is secondarily transferred onto the recording paper P under the influence of the secondary transfer electric field and the nip pressure. In combination with the white color, a full color toner image is obtained. The recording paper P having the full-color toner image formed on the surface in this way is separated from the secondary transfer roller 21 and the intermediate transfer belt 22 by the curvature when passing through the secondary transfer nip. Then, the toner is fed into the fixing device 40 via the post-transfer conveyance path.

  The transfer residual toner that has not been transferred to the recording paper P adheres to the intermediate transfer belt 22 after passing through the secondary transfer nip. This is cleaned from the belt surface by a belt cleaning device 71 in contact with the front surface of the intermediate transfer belt 22. A cleaning backup roller 72 disposed inside the loop of the intermediate transfer belt 22 backs up the cleaning of the belt by the belt cleaning device 71 from the inside of the loop.

  The fixing device 40 as a fixing unit is provided with a fixing roller 45 containing a heat source such as a halogen lamp, and a pressure roller 47 that rotates while contacting the fixing roller 45 with a predetermined pressure. 45 and the pressure roller 47 form a fixing nip. The recording paper fed into the fixing device 40 is sandwiched between the fixing nips such that the unfixed toner image carrying surface is in close contact with the fixing roller 45. Then, the toner in the toner image is softened by the influence of heating and pressurization, and the full-color image is fixed.

  When the single-sided print mode is set by an input operation to an operation unit including a numeric keypad (not shown) or a control signal sent from a personal computer (not shown), the recording paper discharged from the fixing device 40 P is discharged to the outside as it is. Then, it is stacked on a stack portion constituted by the upper surface of the upper cover 56 of the housing.

  In the present embodiment, the process units 26K, C, M, and Y and the optical writing unit 27 constitute a toner image forming unit that forms a toner image.

  The upper cover of the printer casing is supported so as to be rotatable about the shaft member 51 as shown by the arrow in the figure, and is opened with respect to the casing by rotating counterclockwise in the figure. It becomes a state. And the upper opening of a housing is exposed greatly. The optical writing unit 70 is also supported so as to be rotatable about the shaft member 51. By rotating counterclockwise in the figure, the upper surfaces of the process units 26K, C, M, Y are exposed. The

  The process units 26Y, 26M, 26C, and 26K are attached and detached by opening the upper cover and the optical writing unit 70. Specifically, after the upper cover and the optical writing unit 70 are opened to expose the upper surfaces of the process units 26K, C, M, and Y, the process units 26Y, M, C, and K are pulled out vertically upward. Is taken out from the main body.

  By removing the upper cover and the optical writing unit 70 for a process unit that is frequently attached and detached, it can be attached and detached while looking at the inside of the enclosure from the upper side without taking an unreasonable posture such as squatting, bending the waist, or bending down. The operation can be confirmed. Therefore, it is possible to reduce the work load and to suppress the occurrence of operation mistakes.

  In the above description, the process unit 26 including the photosensitive unit 10K and the developing unit 23K is detachable from the apparatus main body. However, the developing unit 23 and the photosensitive unit 10 are separately detachable from the apparatus main body. Also good.

Next, toner supply to the developing unit 23, which is a characteristic part of the printer, will be described.
As shown in FIG. 2, the developing unit 23K is provided with remaining amount detecting means 302K for detecting the remaining amount of toner in the developing unit (in the toner hopper 86). Specifically, a piezoelectric sensor is provided in the development unit, and the remaining amount in the development unit is detected by the output of the piezoelectric sensor, or a detection window is provided in the development unit, and toner is present in the detection window by the transmission type optical sensor. It is detected whether the toner in the developing unit is bulky, and the remaining amount is detected from the bulk.

  When the control unit 300 detects that the amount of toner in the developing unit has fallen below a certain threshold by the remaining amount detection unit 302K, the control unit 300 determines that the toner has ended, and notifies the user by the notification unit 303 such as a display panel. Informs the user that the toner needs to be replenished and prompts the user to replenish the toner. The user supplies new toner to the developing unit 23 based on an instruction from the notification unit 303.

  The new toner T1 has good charging characteristics because the external additive for adjusting the fluidity and chargeability externally added to the toner particle surface is not detached or embedded in the particles. Yes. However, as the number of printed sheets is increased, stress due to stirring or the like is applied, and the external additive is detached or buried in the particles, so that the charging characteristics are deteriorated and charging becomes difficult. Such insufficiently charged toner is less susceptible to the potential difference between the developing roller and the photoconductor, and may adhere to the non-latent image region and cause background staining.

  For this reason, the control unit 300 controls the developing power supply 301 that applies a developing bias, which is a developing condition, to the developing roller 81 according to the number of printed sheets, the number of rotations of the photosensitive member 24, and the like. Bias control is performed. When the new toner is supplied, the control unit 300 resets the number of printed sheets, the number of rotations of the photosensitive member, and the like, and switches to a developing bias corresponding to the new toner T1. That is, the control unit 300 and the development power supply 301 constitute development condition changing means.

Here, conventional toner supply will be described with reference to FIGS.
FIG. 3 is a diagram for explaining conventional toner replenishment. Since the development units 23Y, 23M, 23C, and 23K for the respective colors have the same configuration, the following description will be made with the color code omitted.
The conventional developing unit 230 is provided with a toner supply port 89 on the upper surface of the hopper 86, and one end of the toner transport tube 111 is connected to the toner supply port 89. The other end of the toner transport tube 111 is connected to a toner supply port 112 a provided on the upper surface of the printer main body exterior 112.

  When the user sets a toner cartridge 110 as a developer storage unit storing new toner T1 in the toner supply port 112a of the main body exterior 112, the new toner T1 in the toner cartridge 110 passes through the toner transport tube 111, The toner drops from the toner supply port 89 to the hopper 86. As a result, toner is supplied to the developing unit 23.

FIG. 4 is a schematic configuration diagram showing a conventional developing unit 230 after toner replenishment.
As shown in FIG. 4, when new toner T1 is supplied from the toner cartridge 110 to the hopper 86 at once, the new toner T1 is deposited on the deteriorated old toner T2, and the new toner T1 is deposited on the old toner T2 layer. A layer of toner T1 is formed. Even if the toner in the developing unit is stirred by the agitator 88, it is difficult to sufficiently mix the new toner T1 and the deteriorated old toner T2, and a layer of the old toner T2 is formed at the lower portion of the toner hopper. End up. As a result, most of image formation immediately after toner batch correction is developed using old toner, and if it is performed with a developing bias corresponding to the new toner T1, background smearing occurs. Therefore, it is conceivable to carry out the development bias corresponding to the old toner T2 until the predetermined number of printed sheets is printed after the toner is replenished. However, the remaining amount detection unit 302 cannot accurately grasp the amount of old toner T2 remaining in the developing unit. More specifically, when a piezoelectric sensor is used as the remaining amount detecting means 302, if the toner amount is uneven between the place where the piezoelectric sensor is placed and the place where it is not placed, the amount is larger than the predetermined amount. In step, it is detected that the remaining amount is a predetermined amount, or in a step smaller than the predetermined amount, it is detected that it is a predetermined amount. Also, when a transmission type optical sensor is used as the remaining amount detecting means 302, an accurate remaining amount is detected when a deviation occurs in the toner amount between the position where the detection window is disposed and the position where the detection window is not disposed. I can't. As a result, the new toner T1 is used for development at a stage earlier than the predetermined number of printed sheets, or the new toner T1 is used for development at a stage later than the predetermined number of printed sheets. As a result, it is difficult to perform optimum bias control, and there arises a problem that image quality fluctuates rapidly.

  Therefore, in the present embodiment, the developing unit 23 is configured such that the toner supply is performed in a posture in which the developing unit 23 is vertically inverted with respect to the posture when the developing unit 23 is set in the printer. This will be specifically described below.

FIG. 5 is a diagram illustrating toner supply using the developing unit 23 of the present embodiment.
FIG. 5A is a diagram illustrating a state when the remaining amount detection unit 302 detects that the remaining amount of toner in the developing unit is equal to or less than a predetermined amount, and FIG. FIG. 5C is a diagram showing a state after replenishing new toner, and FIG. 5D is a diagram illustrating the developing unit 23 after replenishing new toner. FIG. 4 is a view showing a posture when the is set in a printer.

  As shown in FIG. 5C, the developing unit 23 according to the present embodiment is a posture (vertically turned upside down with respect to the posture when the printer is set) in a state where new toner T1 is supplied to the developing unit 23 at once. A toner replenishing port 89 is provided at a position vertically above the draft surface of the toner in the hopper portion 86 when it is referred to as a reverse posture. Specifically, as shown in FIG. 5A, the surface of the hopper 86 that faces the photosensitive member (the left side in the drawing) protrudes further toward the photosensitive member than the developing roller 81, and faces the developing roller 81 of the hopper 86. A toner replenishing port 89 is provided at a position protruding to the left in the drawing from the developing roller 81 of 90a. When the toner is not replenished, a lid member 90 is attached to the toner replenishing port 89 to close the toner replenishing port 89.

  As shown in FIG. 5A, when the amount of toner in the developing unit falls below a predetermined amount, the remaining amount detecting means 302 detects that fact, removes the developing unit 23, and prompts toner replenishment, etc. The notification means 303 notifies the user.

  The user rotates the upper cover 56 and the optical writing unit 27 (see FIG. 1) based on the instruction from the notification unit 303, pulls the developing unit 23 vertically upward, and removes it from the main body. Then, as shown in FIG. 5B, the developing unit 23 is set to a posture (reversed posture) that is vertically reversed with respect to the posture when set in the printer (hereinafter referred to as a normal posture). And place it on a table 120 such as a desk. An upper surface 86a of the hopper portion 86 of the developing unit 23 (a lower surface when it is vertically inverted) is a surface parallel to the horizontal plane. For this reason, even if the developing unit is placed in the inverted posture, it can be stably placed on a horizontal surface such as the table 120.

  Further, when the developing unit 23 is placed on the table 120 in the inverted posture, the old toner T2 remaining below the hopper 86 falls to the upper surface 86a of the hopper 86 (the lower surface in the inverted posture).

  As described above, when the developing unit 23 is placed on the stand 120 in the inverted posture, the lid member 90 is removed from the toner supply port 89. Then, the toner cartridge 110 is set in the opened toner supply port 89. Since the toner replenishing port 89 is provided at a position not facing the developing roller protruding from the developing roller 81 toward the photoreceptor, the toner cartridge 110 is set in the toner replenishing port 89 without interfering with the developing roller 81. Can do. After the toner cartridge 110 is set in the toner supply port 89, the seal member (not shown) attached to the toner supply port 110a of the toner cartridge 110 is peeled off, and all the new toner T1 stored in the toner cartridge 110 is removed. Collective supply from the supply port 89 to the hopper 86 is performed.

  The toner replenishing port 89 is provided at a position vertically above the draft surface of the toner in the hopper 86 when the developing unit 23 is turned upside down with new toner T1 replenished to the developing unit 23. Therefore, all the new toner T1 stored in the toner cartridge can be supplied from the toner supply port 89 (FIG. 5C).

  As shown in FIG. 5C, the new toner T1 replenished in the toner cartridge 110 accumulates on the old toner T2 that has fallen onto the upper surface 86a of the hopper (the lower surface in the reverse orientation). Then, as shown in FIG. 5D, when the developing unit 23 is returned to the normal posture, an old toner T2 layer is formed on the new toner T1 layer. Thus, when the developing unit 23 supplied with the new toner T1 is set in the printer, the lower portion of the hopper 86 is filled with the new toner T1. When the new toner T1 is supplied to the hopper 86 at once, the control unit 300 resets the number of prints, the number of rotations of the photosensitive member 24, and the like, and switches to a developing bias corresponding to the new toner T1, thereby obtaining a good image. Can be formed.

  Further, the old toner T2 layer above the new toner T1 layer is mixed with the new toner T1 in the hopper 86 by the stirring of the agitator 88, and the old toner T2 layer disappears. The amount of the old toner T2 is overwhelmingly smaller than the amount of the new toner T1. For this reason, when the old toner T2 is dispersed in the new toner T1 by the stirring of the agitator 88, the characteristics of the toner in the toner hopper are almost the characteristics of the new toner T1. Therefore, even if the developing power supply 301 that applies the developing bias to the developing roller 81 is controlled in accordance with the number of printed sheets, the number of rotations of the photosensitive member 24, and the like thereafter, a deteriorated image is not formed.

  Next, a modified example will be described.

[Modification 1]
FIG. 6 is a schematic configuration diagram of the process unit 26 including the developing unit 23 of the first modification.
As shown in FIG. 6, the developing unit 23 of the first modification includes a waste toner collecting container 16.
As shown in the figure, the waste toner collecting container 16 is provided on the opposite side of the developing unit from the photosensitive unit 10. The toner supply port 89 is provided at a location facing the upper surface of the waste toner collection container 16.

FIG. 7 is a schematic diagram illustrating a conveyance path for conveying the waste toner removed by the cleaning device 83.
As shown in FIG. 7, the waste toner removed from the surface of the photoreceptor 24 by the cleaning blade 83a of the cleaning device 83 is transported to the waste toner transport path 14 by the waste toner coil 83b. Then, the waste toner transported to the waste toner transport path 14 is transported toward the waste toner collection container 16 and collected in the waste toner collection container 16.

FIG. 8 is a schematic perspective view showing a state where the waste toner collecting container 16 is detached from the developing unit 23.
As shown in FIG. 8, a waste toner collection port 19 is provided on the front side of the waste toner collection container 16 in the drawing to collect the waste toner conveyed in the waste toner conveyance path 14. Further, in order to fill the waste toner collected from the waste toner collection port 19 into the waste toner collection container 16 that is long in the paper width direction, the conveyance screw 17 conveys the waste toner in the collection container from the front side to the back side in the figure. Is provided in the waste toner collecting container. A drive gear 18 is provided at the rear end of the rotation shaft of the conveying screw 17 in the drawing. The drive gear 18 is connected to a drive motor (not shown) which is a drive source provided in the apparatus main body. A driving force of a driving motor (not shown) is transmitted to the conveying screw 17 via the driving gear 18, so that the conveying screw 17 rotates and waste toner collected from the waste toner collecting port 19 is moved to the rear side of the waste toner collecting container. Transport to.

  Although not shown, a sealing portion made of a sponge member or the like is formed around the toner supply port 89, and when the waste toner collection container 16 is attached to the developing unit 23, waste toner is collected. The toner supply port 89 is sealed in contact with the upper surface of the collection container 16. Accordingly, it is possible to prevent the toner from leaking from the toner supply port 89 through the space between the developing unit 23 and the waste toner collecting container 16.

  In addition, guide portions 122 are provided on the front side and the back side of the upper surface of the waste toner collecting container 16 in the paper width direction. A guide rail 231 for guiding the guide portion 122 is provided on the front side and the back side in the paper width direction of the surface of the developing unit 23 that faces the upper surface of the waste toner collection container 16.

FIG. 9 is a schematic perspective view when the waste toner collecting container 16 is inverted in the vertical direction with respect to the posture inside the apparatus main body.
As shown in FIG. 9, the edge 191 of the waste toner collection port 19 protrudes from the side surface 161 of the waste toner collection container 16. A seal member 16 a is attached to the side surface 161 of the waste toner collecting container 16. After removing the waste toner collection container 16 from the developing unit 23, the seal member 16a is peeled off from the side surface 161, and the seal member 16a is attached so as to cover the waste toner collection port 19, thereby closing the waste toner collection port 19. Can do.

FIG. 10 is a schematic configuration diagram showing the waste toner conveyance path 14. FIG. 10A is a schematic configuration diagram of the waste toner conveyance path 14 when the waste toner collection container 16 is detached from the development unit 23, and FIG. 10B is a diagram illustrating the waste toner collection container 16 in the development unit 23. FIG. 3 is a schematic configuration diagram of a waste toner conveyance path 14 when attached.
As shown in FIG. 10, in the waste toner transport path 14, a waste toner transport belt 14a stretched around a driving roller 141a and a driven roller 141b is provided. Wall portions 142 are provided on the outer peripheral surface of the waste toner conveyance belt 14a at equal intervals in the movement direction of the waste toner conveyance belt 14a. The wall 142 has the same width as the belt width. Further, the top surface of the waste toner conveyance path 14 has a height that makes contact with the lower surface of the waste toner conveyance path 14 without any gap. The wall 142 has a thickness that does not bend due to frictional force with the waste toner conveyance path 14. The waste toner transport belt 14a is rotated counterclockwise in the figure, and the waste toner T3 transported to the waste toner transport path 14 by the waste toner coil 83b is held by the wall 142 and directed toward the waste toner collection container 16. Transport.

  A waste port 14b to which the waste toner collection port 19 of the waste toner collection container 16 is connected is provided at the right end of the waste toner conveyance path 14 in the drawing (end on the side of the waste toner collection container 16). Moreover, it has the shutter member 14c which opens and closes this connection port 14b. The shutter member 14c is provided with a handle 14c1. When the waste toner collecting container 16 is removed from the developing unit 23, the user holds the handle 14c1 and pulls it up vertically, thereby releasing the shutter member 14c1. 14c moves vertically upward, and the connection port 14b is closed as shown in FIG. Thereby, it is possible to prevent the waste toner T3 in the waste toner conveyance path 14 from being scattered from the connection port 14b after the waste toner collection container 16 is removed.

  As shown in FIG. 10B, when the waste toner collecting container 16 is attached to the developing unit 23, the user holds the handle 14c1 and pushes it down vertically, and moves the shutter member 14c vertically downward. The connection port 14b is opened. Next, as shown in FIG. 11, the guide unit 122 of the toner recovery container is moved obliquely upward in the drawing while guiding the guide part 122 of the toner recovery container by the guide rails 231 provided at both ends of the developing unit 23 in the paper width direction. Then, as shown in FIG. 10B, the waste toner collection container 16 is positioned and fixed to the developing unit 23 by fitting the edge 191 of the waste toner collection port 19 to the connection port 14b. Further, as it moves toward the photosensitive unit 10, the guide rails 231 provided at both ends of the developing unit 23 in the paper width direction are arranged so that the interval between the guide rails 231 decreases, and the guide portion 122 of the waste toner collection container 16 is arranged along the guide rail 231. Then, the guide part 122 comes into contact with the guide rail 231 and the waste toner collecting container 16 is lightly press-fitted by the guide rail 231. As a result, the waste toner collecting container 16 is held in the developing unit 23.

Next, toner supply in Modification 1 will be described.
In the first modification, when the new toner T1 is replenished to the developing unit 23, the upper cover 56 and the optical writing unit 70 are opened, and the process unit 26 is pulled out from the main body in the vertical upward direction. Next, the developing unit 23 is moved in the horizontal direction. Then, the waste toner collecting container 16 held in the developing unit 23 also moves in the horizontal direction together with the developing unit 23, and the edge 191 of the waste toner collecting port 19 and the connection port 14b of the waste toner conveying path 14 are fitted. The developing unit 23 and the photosensitive unit 10K are separated. Then, as shown in FIG. 12, the developing unit 23 is installed on the table 120 in an inverted posture.

  Next, as shown in FIG. 13, the waste toner collection container 16 is slid in parallel with the surface of the development unit 23 facing the upper surface of the waste toner collection container 16 and removed from the development unit 23, and the waste toner collection port 19 is removed. The waste toner collection port 19 is closed by sticking the seal member 16a to the surface. Thereby, it is possible to prevent the waste toner T3 in the waste toner collection container from leaking from the waste toner collection port 19. The removed waste toner collection container 16 is sent to a collection designated place designated by the manufacturer. The waste toner container 16 collected by the manufacturer is cleaned and reused in factory equipment. When the waste toner collecting port 19 is removed from the developing unit 23, the toner replenishing port 89 is opened. Further, the shutter member 14c is moved to close the connection port 14b of the waste toner conveyance path 14.

  Next, as shown in FIG. 13, the toner transport tube 111 of the toner cartridge 110 is set in the toner supply port 89, and new toner T <b> 1 in the toner cartridge is supplied to the developing unit 23 all at once. Then, the toner cartridge 110 is removed, and the empty waste toner collection container 16 is attached to the developing unit 23. When the waste toner collection container 16 is attached to the developing unit 23, a sealing member (not shown) provided around the toner supply port 89 contacts the waste toner collection container 16, and the toner supply port 89 is sealed. Thereby, when the developing unit 23 is returned to the normal posture, the toner does not leak from the toner supply port 89. Then, the shutter member 14c is moved to open the connection port 14b of the waste toner conveyance path 14, and the edge 191 of the waste toner collection container 16 is fitted to the connection port 14b. The mounting process unit 26 is attached to the apparatus main body.

  Since the developing unit 23 of Modification 1 has the waste toner collecting container 16, the waste toner collecting container 16 can be collected when the developing unit 23 is replenished with toner. Further, since the waste toner collection container 16 is configured to be detachable from the developing unit 23, the waste toner can be processed by simply replacing the waste toner collection container 16. Further, in the factory work, the waste toner can be processed by only bringing the waste toner collection container 16 into the dust collection facility. Therefore, compared to a configuration in which the waste toner collection container 16 is not removable from the developing unit 23, the waste toner can be collected and processed easily.

  In the above description, the developing unit 23 and the photosensitive unit 10K are separated, and only the developing unit 23 is installed on the table 120 in an inverted posture. However, the developing unit 23 and the photosensitive unit 10K are not separated and the process is performed. The unit 26 may be placed on the table 120 in a reversed posture. In this case, in order to allow the connection port 14b of the waste toner conveyance path 14 and the edge 191 of the waste toner collection container 16 to be fitted, the surface of the developing unit 23 that faces the upper surface of the waste toner collection container 16 is leveled. To do. Thus, the waste toner collection container 16 is slid with respect to the development unit without separating the development unit 23 from the photosensitive unit 10, thereby connecting the edge 191 of the waste toner collection port 19 and the waste toner transport path 14. The fitting with the opening 14 b is released, and the waste toner collection container 16 can be removed from the developing unit 23.

  Further, only the developing unit 23 may be detachable from the apparatus main body. In this case, for example, it is necessary to devise such as providing the connection port 14 b of the waste toner transport path 14 on the upper surface of the waste toner transport path 14. In this case, it is desirable that the engagement relationship between the waste toner collecting container 16 and the developing unit 23 is close to a right angle with the attaching / detaching direction of the developing unit 23 to the apparatus main body. Accordingly, it is possible to adopt a configuration in which the waste toner collection container 16 is detached from the development unit 23 by simply sliding the waste toner collection container 16 with respect to the development unit 23. Specifically, if the developing unit 23 is mounted on the apparatus main body in a vertical direction, the waste toner collection container 16 is mounted by sliding in the horizontal direction with respect to the developing unit 23.

[Modification 2]
FIG. 14 is a schematic configuration diagram of a toner cartridge in the developing unit of the second modification.
In the second modification, the toner cartridge 110 after replenishing new toner is used as a waste toner collecting container.
As shown in FIG. 14B, the toner cartridge 110 has a toner supply port 110a on the surface facing the toner supply port 89, and a supply port shutter member 113 for opening and closing the toner supply port 110a. Except for this point, it has substantially the same configuration as the waste toner collecting container 16 shown in FIG.

  As shown in FIG. 14, when the new toner T <b> 1 is stored in the toner cartridge 110, the toner supply port 110 a is closed by the supply port shutter member 113. The waste toner collection port 19 is closed by a seal member 19a.

Next, toner replenishment in Modification 2 will be described with reference to FIG.
As shown in FIG. 15A, after the developing unit 23 is installed on the table 120 in a reverse orientation to replenish toner, as shown in FIG. 15B, the toner cartridge 110 containing the waste toner T3 is stored. Is removed from the developing unit 23. As shown in FIG. 15C, the toner cartridge 110 containing the new toner T1 is attached to the developing unit 23. Then, the supply port shutter member 113 is slid, the toner supply port 110a is opened, and the new toner T1 in the toner cartridge 110 is supplied to the developing unit 23. After supplying new toner, the supply port shutter member 113 is slid to close the toner supply port 110a. Further, the seal member 19a that closes the waste toner collection port 19 is peeled off to make the waste toner collection port 19 communicate with the connection port 14b of the waste toner conveyance path 14, and then the developing unit 23 is connected to the apparatus main body or the photoconductor. Mount on the unit 10. As a result, the waste toner T3 transported from the waste toner transport path 14 to the toner cartridge 110 after replenishing the new toner T1 is collected.

  Thus, by using the toner cartridge 110 after replenishing the new toner T1 as a waste toner collecting container, the time for performing the waste toner collecting operation and the toner replenishing operation can be shortened as compared with the first modification. That is, in Modification 1, it is necessary to collect the waste toner collection container, attach the toner cartridge, collect the toner cartridge after replenishing the new toner T1, and attach the empty waste toner collection container. However, in the second modification, the waste toner collecting work and the toner replenishing work can be performed only by collecting the toner cartridge storing the waste toner and attaching the toner cartridge. Can be simplified.

  Further, when the process unit 26 is attached to the apparatus main body with the toner supply port 110a opened, the replenished new toner flows backward from the toner supply port 110a to the toner cartridge 110. Therefore, when the toner supply port 110a is open, it is preferable that the supply port shutter member 113 interferes so that the process unit 26 cannot be attached to the apparatus main body. Further, if the process unit 26 is attached to the apparatus main body without removing the seal member 19a that seals the waste toner collection port 19, the waste toner T3 cannot be collected in the toner cartridge 110, and therefore the seal member 19a is attached to the apparatus main body. It is also possible to provide a seal detection means for detecting the above, and when the seal detection means detects a seal, the notification means may notify that the seal member 19a is instructed to be peeled off. As an example of the seal detection means, a transmissive optical sensor or the like can be used. When the seal member 19a is not peeled off, the portion pinched by the user when the seal member 19a is peeled off causes the light from the light emitting element to be emitted. The presence or absence of the seal member 19a can be detected by disposing the transmission type sensor at a location where it is blocked.

What has been described above is merely an example, and the present invention has specific effects for each of the following aspects (1) to (8).
(1)
Development in which a developer such as toner is carried on the surface and moved, and the developer is supplied to the latent image on the surface of the latent image carrier in the development area facing the latent image carrier such as the photosensitive member 24 for development. Toner supply such as a roller 81, a developer container such as a hopper 86 for accommodating the developer, and a toner supply that pumps up the developer accumulated in the lower part of the developer container and supplies the developer to the developer carrier Development such as a toner supply port 89 for supplying a developer supply member such as a roller 80 and a new developer in a developer storage container such as a toner cartridge 110 containing a new developer to the developer storage unit. In the developing unit 23 having a developer replenishing port, the developing unit 23 is configured to be detachable from the main body of the image forming apparatus, and the developer in a state where new developer in the developer container is replenished in a lump. Development unit 23 is in a vertically inverted position (reversed position) with respect to the position when the image forming apparatus main body is mounted (reversed position), the developer replenishing port is more than the draft surface of the developer in the developer accommodating portion. The developer replenishing port is arranged so as to be vertically upward.
By providing such a configuration, as described in the embodiment, it is possible to supply the new developer with the developing unit 23 in the inverted posture. By replenishing the new developer in the reverse orientation, when the development unit 23 after the replenishment of the new developer is brought into the normal posture (the posture when the apparatus main body is mounted), the lower part of the developer container is replaced with the new developer. can do. Thereby, the latent image on the latent image carrier can be developed satisfactorily by setting the developing condition after supplying the new developer to the developing condition corresponding to the new developer.

(2)
In the developing unit according to the aspect described in (1), the developing unit can be placed on a horizontal plane in a vertically inverted posture with respect to the posture when the image forming apparatus main body is mounted.
With such a configuration, as described in the embodiment, the developing unit 23 can be installed in a horizontal posture on a horizontal plane without using a jig or the like.

(3)
Further, the developing unit according to the above aspect (1) or (2) is provided with a waste toner collecting container 16 for storing waste toner collected from the surface of the latent image carrier.
With such a configuration, as described in the first modification, it is possible to supply new developer and collect waste toner at a time.

(4)
In the developing unit according to the aspect described in (3), the waste toner collecting container 16 is configured to be detachable from the developing unit.
By providing such a configuration, as described in the first modification, the waste toner can be collected by replacing the eight collection container 16 containing the waste toner with an empty waste toner collection container 16. In the factory, waste toner can be processed by bringing only the waste toner collecting container 16 into the dust collection facility. As a result, the waste toner can be easily processed as compared with a configuration in which the waste toner collection container is not removable from the developing unit.

(5)
Further, in the developing unit according to the aspect described in (4) above, the developer container is set at the attachment position of the waste toner collecting container 16 so that the new developer in the developer container becomes the developer. The developer is supplied to the developer container through a supply port, and the developer container after the new developer is supplied to the developer container is used as the waste toner collection container.
With this configuration, as described in the second modification, the waste toner is collected by collecting the developer container in which the waste toner is stored and setting the developer container in which the new developer is stored. Processing operations and toner supply operations can be performed.

(6)
Further, at least the latent image carrier and the developing unit in an image forming apparatus including a latent image carrier such as the photosensitive member 24 that carries the latent image, and a developing unit that develops the latent image on the latent image carrier. In the process cartridge in which the image forming apparatus main body is held on a common holding body as a unit and is detachable from the image forming apparatus main body, the developing unit according to any one of the above aspects 1 to 5 is used as the developing unit. .
With this configuration, the latent image carrier and the developing unit can be exchanged together, and consumable parts can be exchanged at a time.

(7)
Also, a latent image carrier such as the photosensitive member 24, a charging means such as a charging device 25 for charging the surface of the latent image carrier, and optical writing for forming an electrostatic latent image on the latent image carrier. In the image forming apparatus having a latent image forming means such as the unit 27 and a developing means for developing the electrostatic latent image, the developing according to any one of the above (1) to (5) is used as the developing means. Use units.
By providing such a configuration, the development condition after replenishing a new developer is set to the development condition corresponding to the new developer, so that a decrease in the image after replenishing the new developer can be suppressed.

(8)
In the image forming apparatus according to the aspect described in (7) above, the development conditions (in this embodiment) when developing the latent image on the latent image carrier according to the deterioration state of the developer in the development unit. , Development bias) (in this embodiment, the control unit 300 and the development power supply 301), and the development condition change unit is configured to supply a new developer to the development unit. Then, the development conditions corresponding to the new developer are changed.
With such a configuration, it is possible to suppress a decrease in the image after the new developer is replenished. Further, even if the developer deteriorates over time, the development conditions corresponding to the deterioration are changed, so that a good image can be maintained over time.

(9)
New development in a developer container such as a toner cartridge 110 from a developer replenishing port such as a toner replenishing port 89 of a developing unit that supplies the developer to the latent image on the surface of the latent image carrier such as the photosensitive member 24 and develops it. In the developer replenishing method for replenishing the developer in a lump, the developing unit in a state where the developer unit is replenished with a new developer in the developer container is vertically oriented with respect to the posture when the image forming apparatus main body is mounted. The developer replenishing port is provided so that the developer replenishing port is vertically above the draft surface of the developer in the developer containing portion when the developer unit is turned upside down. Removing the image forming apparatus main body from the image forming apparatus main body and setting the image forming apparatus main body to a posture in which the image forming apparatus main body is vertically inverted. In a posture in which is vertically upside down with respect to the developer supply method characterized by having a new developer and a step of supplying from the developer supply port.
By replenishing the developer by such a method, the old developer in the developing unit can be positioned vertically upward when the posture when the image forming apparatus main body is mounted after the replenishment of the developer. Therefore, when the developing unit of the developing unit 23 is set to the posture when the image forming apparatus main body is mounted, the developing unit can be filled with the new developer by being configured to be positioned on the lower side. Development can be performed using a new developer.

10: Photoconductor unit 14: Waste toner transport path 14a: Waste toner transport belt 14b: Connection port 14b: Connection port 14c: Shutter member 16: Waste toner collection container 16a: Seal member 17: Transport screw 18: Drive gear 19: Waste Toner recovery port 19a: seal member 23: developing unit 24: photoconductor 25: charging device 26: process unit 27: optical writing unit 41: toner writing port 70: optical writing unit 80: toner supplying roller 81: developing roller 83b : Waste toner coil 86: Hopper part 86a: Upper surface 87: Developing part 88: Agitator 89: Toner replenishing port 90: Cover member 110: Toner cartridge 110a: Toner supply port 113: Supply port shutter member 120: Stand 122: Guide unit 142 : Wall portion 191: Edge portion 231: Guide rail 300: Control portion 301: Development power source 3 2: remaining amount detection means 303: informing means T1: new toner T2: old toner T3: waste toner

JP-A-6-83186 JP 7-325484 A

Claims (9)

A developer carrying body that carries the developer on the surface, moves the surface, and supplies the developer to the latent image on the surface of the latent image carrying body in a development region facing the latent image carrying body;
A developer accommodating portion for accommodating the developer;
A developer supply member that pumps up the developer accumulated in the lower part of the developer container and supplies the developer to the developer carrier;
In a development unit comprising a developer replenishment port for replenishing a new developer in a developer storage container containing a new developer to the developer containing portion,
The developing unit is configured to be detachable from the image forming apparatus main body,
When the developing unit in a state where the new developer in the developer container is replenished in a lump is turned upside down with respect to the posture when the image forming apparatus main body is mounted, the developer replenishing port However, the developer replenishing port is disposed so as to be vertically above the draft surface of the developer in the developer container. The developing unit according to claim 1.
A developing unit characterized in that it can be placed on a horizontal plane in a vertically inverted orientation with respect to the orientation when the image forming apparatus main body is mounted. The developing unit according to claim 1 or 2,
A developing unit comprising a waste toner collecting container for storing waste toner collected from the surface of the latent image carrier. The development unit according to claim 3.
A developing unit, wherein the waste toner collecting container is configured to be detachable from the developing unit. The development unit according to claim 4.
By setting the developer storage container at the attachment position of the waste toner collection container, a new developer in the developer container is replenished to the developer storage portion via the developer supply port. Configured to be
A developing unit comprising: a developer container after the new developer is supplied to the developer container as the waste toner collecting container. In an image forming apparatus comprising a latent image carrier that carries a latent image and a developing unit that develops the latent image on the latent image carrier, at least the latent image carrier and the developing unit are shared as one unit. In the process cartridge that is held by the holding body and is detachable from the image forming apparatus main body,
6. A process cartridge using the developing unit according to claim 1 as the developing means. A latent image carrier;
Charging means for charging the surface of the latent image carrier;
Latent image forming means for forming an electrostatic latent image on the latent image carrier;
In an image forming apparatus having a developing means for developing the electrostatic latent image,
An image forming apparatus using the developing unit according to claim 1 as the developing unit. The image forming apparatus according to claim 7.
Development condition changing means for changing development conditions when developing the latent image on the latent image carrier according to the deterioration state of the developer in the development unit;
The image forming apparatus according to claim 1, wherein the developing condition changing means changes the developing condition to correspond to a new developer when a new developer is supplied to the developing unit. In a developer replenishing method for replenishing a new developer in a developer container from a developer replenishing port of a developing unit for supplying a developer to a latent image on the surface of a latent image carrier for development.
When the developing unit in a state where all the new developer in the developer container is replenished to the developing unit is turned upside down with respect to the posture when the image forming apparatus main body is mounted, the developing unit The developer supply port is provided so that the developer supply port is vertically above the draft surface of the developer in the developer container.
Removing the developing unit from the main body of the image forming apparatus and placing the developing unit in a vertically inverted position with reference to the posture when the image forming apparatus main body is mounted;
Supplying the developer from the developer replenishing port in a posture in which the developing unit is vertically inverted with respect to the posture when the image forming apparatus main body is mounted. Method.

Images