JP2015022239A - Developing device, assembly and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress excessive replenishment of toner in a developing device into which toner is replenished from a replenishing port.SOLUTION: A developing device 24 includes: a housing part 244D that houses in a housing chamber 244, a supply part supplying a developer G including toner T and a carrier CA to a developing member 242 while conveying the developer G in an own shaft direction, and that is replenished with the toner T from above through a replenishing port 250; and a rotator 249 that is provided above the housing chamber 244, faces the replenishing port 250, and when an upper surface of the conveyed developer G in the supply chamber 244 is more than a predetermined height L, absorbs the developer G while rotating around the own shaft, conveys the developer G to an interior of the replenishing port 250, and causes the developer G to stay in the replenishing port 250.

Description

  The present invention relates to a developing device, an assembly, and an image forming apparatus.

  In Patent Document 1, the developer transported in the developer circulation transport path (V1 + V2) is located upstream of the developer discharge port (7) in the developer transport direction, and the shaft of the stirring transport member (R1 + R2). A configuration of a developing device that is close to the above is disclosed.

JP 2009-211087 A

  An object of the present invention is to suppress excessive replenishment of toner in a developing device that replenishes toner from a replenishing port.

  The developing device according to claim 1 of the present invention accommodates a supply section for supplying the developer to the developing member while conveying the developer including toner and a carrier in its own axial direction, and the upper part through the replenishing port. A storage unit for supplying toner from above, and provided above the storage chamber, facing the replenishing port, and having an upper surface of the developer conveyed in the supply chamber at a predetermined height or more. A rotating body that adsorbs the developer, conveys it into the replenishing port, and stays in the replenishing port while rotating about its own axis.

  The developing device according to claim 2 of the present invention is the developing device according to claim 1, wherein when the upper surface of the developer in the accommodation chamber is lower than the predetermined height, the rotating body rotates about its own axis. However, the toner in the replenishing port is conveyed to the drop area.

  The developing device according to a third aspect of the present invention is the developing device according to the second aspect, wherein the rotator is configured so that the toner in the replenishing port is more concentrated on the rotator than the adsorption region that adsorbs the developer in the storage chamber. Transport to the fall area upstream in the rotational direction.

  The developing device according to a fourth aspect of the present invention is the developing device according to the second or third aspect, wherein the storage chamber is formed from a first chamber that stores the supply unit and a direction orthogonal to the own axis of the developing member. As seen, before the developer formed outside the developing area of the developing member and flowing in from the first chamber is returned to the upstream side in the transport direction by the supply unit in the first chamber via the circulation path. A second chamber passing therethrough, wherein the rotating body is arranged to be directly above the second chamber.

  The developing device according to a fifth aspect of the present invention is the developing device according to the third or fourth aspect, wherein the supply chamber is viewed from a first chamber in which the supply section is accommodated, and the developing member in its own axial direction. Thus, the developer that is formed on the opposite side of the developing member across the first chamber and overflows from the first chamber flows upstream in the transport direction of the first chamber in the first chamber via the circulation path. A third chamber that passes through before returning, and the rotating body is arranged to be directly above the third chamber.

  A developing device according to a sixth aspect of the present invention is the developing device according to any one of the first to third aspects, wherein the rotating body is a part of the developing member that extends in a direction of its own axis. And a portion located outside the developing region of the developing member when viewed from a direction orthogonal to the own axis of the developing member.

  The assembly according to claim 7 of the present invention develops an image carrier on which a latent image is formed and a latent image formed on the outer peripheral surface of the image carrier as a toner image. And the image forming apparatus main body are assembled so as to be interchangeable as a unit.

  According to an eighth aspect of the present invention, there is provided an image forming apparatus, a charging device for charging the outer peripheral surface of the image holding member, and a latent image on the outer peripheral surface of the image holding member charged by the charging device. A latent image forming device for forming, a developing device according to claim 1 for developing the latent image as a toner image, and a transfer device for transferring the toner image to a transfer target. .

  According to the developing device of the first aspect of the present invention, excessive replenishment of toner is suppressed as compared with the case where the rotating body of this configuration is not provided.

  According to the developing device of the second aspect of the present invention, the toner is replenished with a simple structure as compared with the case where the rotating body does not convey the toner from the replenishing port to the storage chamber.

  According to the developing device of the third aspect of the present invention, compared to the case where the dropping area and the suction area are the same, it is less susceptible to the toner drop in the suction area.

  According to the developing device of the fourth aspect of the present invention, development defects caused by the replenishment of toner are suppressed as compared with the case where the rotating body is disposed on the first chamber.

  According to the developing device of the fifth aspect of the present invention, development defects caused by the replenishment of toner are suppressed as compared with the case where the rotating body is disposed on the first chamber.

  According to the developing device of the sixth aspect of the present invention, the number of parts is reduced as compared with the case where the rotating body is not formed on a part of the developing member extending in the own axis direction.

  According to the assembly of the seventh aspect of the present invention, development failure caused by excessive replenishment of toner is suppressed as compared with the case where the present configuration is not provided.

  According to the image forming apparatus of the eighth aspect of the present invention, image formation defects caused by excessive replenishment of toner are suppressed as compared with the case where the present configuration is not provided.

1 is a schematic diagram illustrating an overall configuration of an image forming apparatus according to a first embodiment. 1 is a schematic diagram illustrating a configuration of an image forming unit included in an image forming apparatus according to a first embodiment. FIG. 3 is a schematic diagram illustrating a configuration of a toner image forming unit included in the image forming unit according to the first embodiment. FIG. 3 is a schematic diagram (cross-sectional view) viewed from the front side showing the configuration of the developing device that constitutes the toner image forming unit according to the first exemplary embodiment. FIG. 3 is a schematic diagram (cross-sectional view) viewed from above showing the configuration of the developing device that constitutes the toner image forming unit according to the first exemplary embodiment. It is a figure which shows operation | movement of the developing device which concerns on 1st Embodiment, Comprising: It is the schematic which shows the case where the upper surface of the developer in a storage chamber is lower than the defined height. It is a figure which shows operation | movement of the developing device which concerns on 1st Embodiment, Comprising: It is the schematic which shows the case where the upper surface of the developer in a storage chamber is more than the defined height. It is the schematic (sectional drawing) seen from the front side which shows the structure of the developing device which concerns on 2nd Embodiment. It is the schematic (sectional drawing) seen from the front side which shows the structure of the developing device which concerns on 3rd Embodiment. It is the schematic (sectional drawing) seen from the upper side which shows the structure of the developing device which concerns on 3rd Embodiment. It is the schematic (sectional drawing) seen from the front side which shows the structure of the developing device which concerns on 4th Embodiment. It is the schematic (sectional drawing) seen from the side surface which shows the structure of the developing device which concerns on 4th Embodiment.

<First Embodiment>
Hereinafter, an example of the first embodiment will be described with reference to the drawings. First, the overall configuration and operation of the image forming apparatus will be described, and then the configuration and operation of the developing device that is the main part of the present embodiment will be described. In the following description, the direction indicated by the arrow H in FIG. 1 is the apparatus height direction, and the apparatus width direction is the direction indicated by the arrow W in FIG. In addition, a direction perpendicular to each of the apparatus height direction and the apparatus width direction (shown by an arrow D as appropriate) is defined as an apparatus depth direction.

<Configuration of image forming apparatus>
FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming apparatus 10 according to the present embodiment as viewed from the front side. As shown in this figure, the image forming apparatus 10 includes an image forming unit 12 that forms an image on a medium P by an electrophotographic method, a medium transport unit 50 that transports the medium P, and a rear side of the medium P on which an image is formed. And a post-processing unit 60 that performs processing and the like. Further, the image forming apparatus 10 includes a control unit 70 that controls the units and the power supply unit 80, and a power supply unit 80 that supplies power to the units including the control unit 70.

(Image forming part)
The image forming unit 12 will be described with reference to FIG. 2 which is a schematic view of the image forming unit 12 viewed from the front side. The image forming unit 12 includes a toner image forming unit 20 that forms a toner image, a transfer device 30 that transfers an image formed by the toner image forming unit 20 to the medium P, and a toner image transferred to the medium P. And a fixing device 40 for fixing.

<Toner image forming section>
The toner image forming unit 20 includes a photosensitive drum 21, a charger 22, an exposure device 23, a developing device 24, and a cleaning device 25. A plurality of toner image forming units 20 are provided so as to form a toner image for each color. In the present embodiment, a toner image forming unit for a total of six colors of first special color (V), second special color (W), yellow (Y), magenta (M), cyan (C), and black (K). 20 is provided. (V), (W), (Y), (M), (C), and (K) shown in FIG. 1 indicate the colors described above. The transfer device 30 is configured to transfer a toner image for six colors onto a medium P at a transfer nip NT from a transfer belt 31 on which toner images for six colors are superimposed and primarily transferred. Here, the photosensitive drum 21 is an example of an image carrier. The charger 22 is an example of a charging device. The exposure device 23 is an example of a latent image forming device.

(Photosensitive drum)
The photosensitive drum 21 is formed in a cylindrical shape, and is driven to rotate around its own axis by a driving unit (not shown). As an example, a photosensitive layer having a negative charging polarity is formed on the outer peripheral surface of the photosensitive drum 21. Note that an overcoat layer may be formed on the outer peripheral surface of the photosensitive drum 21. The photosensitive drums 21 of the respective colors are arranged in a straight line along the apparatus width direction when viewed from the front.

(Charger)
The charger 22 charges the outer peripheral surface (photosensitive layer) of the photosensitive drum 21 to a negative polarity. In the present embodiment, the charger 22 is a corona discharge (non-contact charging) scorotron charger.

(Exposure equipment)
The exposure device 23 is configured to form an electrostatic latent image on the outer peripheral surface of the photosensitive drum 21. Specifically, the exposure light L (see FIG. 3) modulated according to the image data received from the image signal processing unit constituting the control unit 70 is applied to the outer peripheral surface of the photosensitive drum 21 charged by the charger 22. It comes to irradiate. An electrostatic latent image is formed on the outer peripheral surface of the photosensitive drum 21 by irradiation of the exposure light L from the exposure device 23. In the present embodiment, the exposure device 23 is configured to expose the surface of the photosensitive drum 21 while scanning the light beam emitted from the light source with an optical scanning means (optical system) including a polygon mirror and an Fθ lens. Yes. In the present embodiment, the exposure device 23 is provided for each color.

(Developer)
The developing device 24 develops, as a toner image, the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 21 with the developer G including the toner T and the carrier CA, so that the toner image is formed on the outer peripheral surface of the photosensitive drum 21. Is supposed to form. The developing device 24 includes at least a container 241 that stores the developer G, and a developing roller 242 that supplies the developer G stored in the container 241 to the photosensitive drum 21 while rotating. A toner cartridge 27 for replenishing toner T is connected to the container 241 through a replenishment path (not shown). The toner cartridges 27 for the respective colors are arranged above the photosensitive drum 21 and the exposure device 23 in the apparatus width direction when viewed from the front, and can be individually replaced. The developing device 24 is a main part of the present embodiment, and will be described later. Here, the developing roll 242 is an example of a developing member.

(Cleaning device)
The cleaning device 25 includes a blade 25 </ b> A that scrapes off the toner T remaining on the surface of the photosensitive drum 21 after the transfer of the toner image to the transfer device 30 from the surface of the photosensitive drum 21. Although not shown, the cleaning device 25 further includes a housing that collects the toner T scraped off by the blade 25A and a transport device that transports the toner T in the housing to a waste toner box.

(Transfer device)
The transfer device 30 performs primary transfer by superimposing the toner image of the photosensitive drum 21 of each color on the transfer belt 31, and secondarily transferring the superimposed toner image to the medium P.

  Specifically, the transfer belt 31 has an endless shape and is wound around a plurality of rolls 32 to determine the posture. In the present embodiment, the transfer belt 31 has an inverted obtuse triangular posture that is long in the apparatus width direction when viewed from the front. Among the plurality of rolls 32, the roll 32D shown in FIG. 2 functions as a drive roll that rotates the transfer belt 31 in the direction of arrow A by the power of a motor (not shown). Of the plurality of rolls 32, the roll 32 </ b> T illustrated in FIG. 2 functions as a tension applying roll that applies tension to the transfer belt 31. Among the plurality of rolls 32, the roll 32 </ b> B illustrated in FIG. 2 functions as a counter roll of the secondary transfer roll 34.

  The transfer belt 31 is in contact with the photosensitive drum 21 of each color from below at the upper side extending in the apparatus width direction with the above-described posture, and the image on each photosensitive drum 21 is transferred from the primary transfer roll 33. Transfer is performed upon application of a voltage. In addition, the transfer belt 31 forms a transfer nip NT by contacting the secondary transfer roll 34 at the apex on the lower end side forming an obtuse angle, and the transfer belt 31 receives the transfer bias voltage from the secondary transfer unit 34 to receive the transfer belt 31. The toner image is transferred to the medium P that passes through the nip NT.

  Here, when the transfer belt 31 is an example of a transfer target, the primary transfer roll 33 is an example of a transfer device. In addition, when the medium P is an example of a transfer target, the transfer belt 31 is an example of a transfer device.

(Fixing device)
The fixing device 40 fixes the toner image onto the medium P on which the toner image has been transferred by the transfer device 30. In the present embodiment, the fixing device 40 is configured to fix the toner image on the medium P by applying pressure while heating the toner image in the fixing nip NF.

[Media transport section]
The medium transport unit 50 includes a medium supply unit 52 that supplies the medium P to the image forming unit 12 and a medium discharge unit 54 that discharges the medium P on which the image is formed. The medium transport unit 50 includes a medium return unit 56 used when images are formed on both surfaces of the medium P, and an intermediate transport unit 58 that transports the medium P from the transfer device 30 to the fixing device 40. ing.

  The medium supply unit 52 supplies the medium P one by one to the transfer nip NT of the image forming unit 12 in accordance with the transfer timing. The medium discharge unit 54 discharges the medium P on which the toner image is fixed by the fixing device 40 to the outside of the apparatus. The medium return unit 56 reverses the medium P and returns it to the image forming unit 12 (medium supply unit 52) when forming an image on the other side of the medium P having the toner image fixed on one side. It has become.

[Post-processing section]
The post-processing unit 60 includes a medium cooling unit 62 that cools the medium P on which the image is formed by the image forming unit 12, a correction device 64 that corrects the curvature of the medium P, and an image that inspects the image formed on the medium P. An inspection unit 66 is included. Each unit constituting the post-processing unit 60 is disposed in the medium discharge unit 54 of the medium transport unit 50.

  The medium cooling unit 62, the correction device 64, and the image inspection unit 66 constituting the post-processing unit 60 are arranged in this order from the upstream side in the medium P discharging direction in the medium discharging unit 54. The post-processing is performed on the medium P in the discharge process.

<Operation of image forming apparatus>
An outline of an image forming process on the medium P by the image forming apparatus 10 and a subsequent processing process will be described.

  Upon receiving the image formation command, the control unit 70 operates the toner image forming unit 20, the transfer device 30, and the fixing device 40. As a result, the photosensitive drum 21 and the developing roll 242 are rotated, and the transfer belt 31 is rotated. Further, the pressure roll 42 is rotated and the fixing belt 411 is rotated. Further, in synchronization with these operations, the control unit 70 operates the medium conveyance unit 50 and the like.

  As a result, the photosensitive drums 21 of the respective colors are charged by the charger 22 while being rotated. In addition, the control unit 70 sends the image data that has been subjected to image processing by the image signal processing unit to each exposure device 23. Each exposure device 23 emits each exposure light L according to the image data and exposes each charged photosensitive drum 21. Then, an electrostatic latent image is formed on the outer peripheral surface of each photosensitive drum 21. The electrostatic latent image formed on each photoconductor drum 21 is developed as a toner image by the developer G supplied from the developing device 24. As a result, the photosensitive drum 21 of each color has the first special color (V), the second special color (W), yellow (Y), magenta (M), cyan (C), and black (K). A corresponding color toner image is formed.

  The toner images of the respective colors formed on the photosensitive drums 21 of the respective colors are sequentially transferred to the rotating transfer belt 31 by applying a transfer bias voltage through the primary transfer rolls 33 of the respective colors. As a result, a toner image in which toner images for six colors are superimposed is formed on the transfer belt 31. This toner image is conveyed to the transfer nip NT by the rotation of the transfer belt 31. The medium P is supplied to the transfer nip NT by the medium supply unit 52 so that the timing of the toner image is conveyed. A toner image is transferred from the transfer belt 31 to the medium P by applying a transfer bias voltage at the transfer nip NT.

  The medium P onto which the toner image has been transferred is conveyed by the intermediate conveyance unit 58 from the transfer nip NT of the transfer device 30 toward the fixing nip NF of the fixing device 40 while being sucked with negative pressure. The fixing device 40 applies heat and pressure (fixing energy) to the medium P that passes through the fixing nip NF. As a result, the toner image transferred to the medium P is fixed to the medium P.

  The medium P discharged from the fixing device 40 is processed by the post-processing unit 60 while being conveyed by the medium discharge unit 54 toward the discharge medium receiving unit outside the apparatus. The medium P heated in the fixing process is first cooled in the medium cooling unit 62. Next, the curvature of the medium P is corrected by the correction device 64. Further, the toner image fixed on the medium P is detected by the image inspection unit 66 for the presence or absence of toner density defects, image defects, image position defects, and the like. Then, the medium P is discharged to the medium discharge unit 54.

  On the other hand, when an image is formed on a non-image surface on which an image of the medium P is not formed (in the case of double-sided printing), the control unit 70 determines the conveyance path of the medium P after passing through the image inspection unit 66 as a medium discharge unit. Switching from 54 to the medium return unit 56. As a result, the medium P is turned upside down and sent to the medium supply unit 52. On the back surface of the medium P, an image is formed (fixed) in the same process as the image forming process on the front surface. The medium P is discharged out of the apparatus by the medium discharge unit 54 through a process similar to the post-processing process after image formation on the surface described above.

<Configuration of main part (developing device)>
As described above, the developing device 24 that is a main part of the present embodiment develops the electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 21 with the developer G including the toner T and the carrier CA as a toner image. . Along with this, the toner T in the developing device 24 is consumed. The developing device 24 is replenished with toner T through a replenishment port 250 described later. Note that the carrier CA in the developing device 24 is not consumed or replenished.

  Hereinafter, an example of the developing device 24 that is a main part of the present embodiment will be described with reference to the drawings. FIG. 4 is a schematic view (cross-sectional view) showing the configuration of the developing device 24 as viewed from the front side. FIG. 5 is a schematic diagram (cross-sectional view) showing a configuration of the developing device 24 as viewed from the upper surface side.

In FIG. 4, the cross-sectional shape of the photosensitive drum 21 is shown by a two-dot chain line in order to clarify the positional relationship between the developing device 24 and the photosensitive drum 21. FIG. 5 shows a state where the upper lid 241A (see FIG. 5) of the container 241 is removed. In FIG. 5, hatching of cross sections other than the container 241 and the replenishing port 250 is omitted. Here, the container 241 is an example of a storage unit.

  4 and 5, the same arrow H, arrow W, and arrow D as those in FIGS. 1 and 2 are shown for the developing device 24. This is the direction in which the developing device 24 is arranged in the image forming apparatus 10. Hereinafter, when describing each member and the like of the developing device 24, these directions are used as necessary.

  As described above, the developing device 24 includes the container 241 and the developing roll 242. Further, as shown in FIGS. 4 and 5, the developing device 24 includes a supply member 243, a stirring member 245, a layer regulating member 248, a rotating body 249, and magnetic members 249A and 249B. Has been. Further, as shown in FIG. 4, a supply chamber 244 in which the supply member 243 is accommodated and an agitation chamber 246 in which the agitation member 245 is accommodated are formed inside the container 241 of the developing device 24. . The supply chamber 244 and the stirring chamber 246 are partitioned by a wall portion 252 formed inside the container 241. The supply chamber 244 is a space in which the supply member 243 in the container 241 is accommodated, and is a space below the height L described later. Here, the supply member 243 is an example of a supply unit. The supply chamber 244 is an example of a storage chamber.

  In the developing device 24, the rotating body 249 and the magnetic members 249A and 249B allow the amount of the developer G in the supply chamber 244, the toner T concentration relative to the developer G, or the concentration ratio of the toner T and the carrier CA (hereinafter referred to as toner T). Is called physical quantity). This will be described later.

<Supply members and supply chamber>
As shown in FIG. 5, the supply member 243 includes a rotation shaft 243A and a spiral helix portion 243B formed on the outer peripheral surface of the rotation shaft 243A. As shown in FIG. 4, a replenishment port 250 for replenishing the supply chamber 244 with toner T is connected to the upper portion of the supply chamber 244.

  As shown in FIG. 5, the supply chamber 244 includes a first chamber 244 </ b> A formed corresponding to the developing area I in the developing roll 242 as viewed from the apparatus width direction, and outside the developing area I. A second chamber 244B formed adjacent to the first chamber 244A and extending from the first chamber 244A in the axial direction of the supply member 243. Note that a rotating body 249 is disposed immediately above the second chamber 244B constituting the supply chamber 244 (see FIG. 4). Here, the development area I refers to an area in the axial direction of the developing roll 242 to which the developer G is supplied from the supply member 243.

  The supply member 243 receives power from a motor (not shown) provided in the image forming apparatus 10 and is rotated about the own axis in the direction of arrow C (see FIG. 4). . When the supply member 243 rotates in the direction indicated by the arrow C, the supply member 243 conveys the developer G in the supply chamber 244 in the traveling direction of the spiral portion 243B (the direction indicated by the arrow F in FIG. 5). G is supplied to the developing roll 242.

  As shown in FIG. 5, openings 252 </ b> A and 252 </ b> B are formed at both ends in the apparatus depth direction in the wall 252 that partitions the supply chamber 244 and the stirring chamber 246. The developer G that has not been supplied to the developing roller 242 and is conveyed to the end in the traveling direction of the spiral portion 243B in the first chamber 244A flows into the second chamber 244B, and further enters the stirring chamber 246 through the opening 252A. It is supposed to be sent. In addition, the toner T replenished to the second chamber 244B through the replenishing port 250 in the supply chamber 244 is also fed into the stirring chamber 246 through the opening 252A together with the developer G that has flowed into the second chamber 244B from the first chamber 244A. It is like that. As shown in FIG. 5, the opening 252A is formed so as to correspond to the second chamber 244B outside the developing region I in the apparatus depth direction.

  The developing roll 242 supplied with the developer G is rotated in the direction of arrow E by the power transmitted by the motor (see FIG. 4). The developer G supplied to the developing roll 242 is transported to the outer peripheral surface of the photosensitive drum 21 with the layer thickness of the developer G regulated by the layer regulating member 248.

<Stirring member and stirring chamber>
As shown in FIG. 5, the stirring member 245 includes a rotating shaft 245A and a helical portion 245B formed on the outer peripheral surface of the rotating shaft 245A.

  The stirring member 245 is connected to the motor. The stirring member 245 receives the power from the motor and is rotated in the direction of arrow C about its own axis (see FIG. 4). When the stirring member 245 rotates in the direction of arrow B, the stirring member 245 conveys the developer G in the stirring chamber 246 while stirring in the traveling direction of the spiral portion 245B (the direction opposite to the direction of arrow F in FIG. 5). It has become.

  The developer G transported to the advancing direction end of the spiral portion 245B in the stirring chamber 246 by the stirring member 245 is upstream of the transport direction of the developer G by the supply member 243 in the supply chamber 244 through the opening 252A. It is supposed to be returned.

  That is, the developer G that has flowed in from the first chamber 244A passes through the second chamber 244B and returns to the upstream side in the transport direction of the developer G by the supply member 243 in the first chamber 244A via the stirring chamber 246. Has been circulated. Here, the stirring chamber 246 is an example of a circulation path.

<Rotating body and magnetic member>
The rotating body 249 has a cylindrical shape as shown in FIG. On the outer peripheral surface of the rotating body 249, a linear groove portion is formed along the own axis direction (see FIG. 5). The groove has an average depth of 90 μm and an average width of 75 μm in the rotation direction. The volume average particle diameter of the carrier CA of the developer G used in the present embodiment is 35 μm, and the average depth and average width of the groove are larger than the volume average particle diameter of the carrier CA. In the present embodiment, the rotating body 249 is made of an aluminum alloy (JIS symbol: A6063).

  As illustrated in FIG. 4, the rotating body 249 is provided above the supply chamber 244 (supply member 243). Specifically, the rotating body 249 is provided so as to partially overlap the supply member 243 when viewed from the apparatus height direction (see FIGS. 4 and 5). As illustrated in FIG. 5, the rotating body 249 is disposed on the downstream side in the traveling direction of the spiral portion 243 </ b> B with respect to the supply member 243. Further, the rotator 249 is rotated in the direction of arrow D when power is transmitted by the motor (see FIG. 4).

  Further, as illustrated in FIG. 4, the rotating body 249 is opposed to the replenishing port 250 through which the toner T replenished in the supply chamber 244 passes. Here, when the developing device 24 (or the rotating body 249) is viewed from the front side, the position of the rotating body 249 with respect to the replenishing port 250 will be described with reference to FIG. The rotation center of the rotator 249 is defined as the center O, the imaginary line in the device width direction passing through the center O is defined as the X axis, and the imaginary line in the device height direction passing through the center O is defined as the Y axis. The positive direction of the X axis is the right side in the apparatus width direction, and the positive direction of the Y axis is the upper side in the apparatus height direction. Then, the rotating body 249 faces the replenishing port 250 in the first quadrant and the second quadrant of the orthogonal coordinate system formed by the X axis and the Y axis.

  Further, as shown in FIG. 4, the rotator 249 is opposed to the upstream wall portion (upstream side wall portion 250 </ b> A) and the downstream wall portion (downstream side wall portion 250 </ b> B) of the replenishment port 250 in the rotation direction of the rotator 249. And facing each other with a gap. Here, the narrowest part of the gap is set larger than the volume average particle diameter of the carrier CA.

  As shown in FIG. 4, the rotator 249 rotates in contact with the toner T accumulated in the replenishing port 250 in a region facing the replenishing port 250. As a result, the rotating body 249 conveys the toner T that has contacted in the replenishing port 250 to a drop area A2 described later. The replenishment port 250 is connected to the toner cartridge 27 described above through a replenishment path (not shown).

  As shown in FIG. 4, magnetic members 249 </ b> A and 249 </ b> B are arranged in a partial region on the inner peripheral surface side of the rotating body 249. Further, the magnetic members 249A and 249B have a long shape extending over the entire area of the rotating body 249 in the own axis direction. The magnetic member 249A has south pole magnetism, and the magnetic member 249B has north pole magnetism.

  As shown in FIG. 4, the magnetic member 249 </ b> A faces the region in the replenishment port 250 (the first quadrant and the second quadrant of the orthogonal coordinate system formed by the X axis and the Y axis) with the rotating body 249 interposed therebetween. Are arranged to be. Further, as shown in FIG. 4, the magnetic member 249B is on the inner peripheral surface side of the rotating body 249, and is in the fourth quadrant of the orthogonal coordinate system formed by the X axis and the Y axis. It arrange | positions so that a surrounding surface may be opposed.

  The developer G is attracted to the outer peripheral surface of the rotator 249 by a magnetic field generated by the magnetic members 249A and 249B arranged on the inner peripheral surface side.

  As shown in FIG. 4, when the upper surface of the developer G in the supply chamber 244 reaches a height L or more, the developer G is adsorbed on the outer peripheral surface of the rotating body 249 in the adsorption area A1. ing. In other words, the rotator 249 is arranged so that the developer G is adsorbed to the outer peripheral surface of the rotator 249 when the upper surface of the developer G in the supply chamber 244 reaches a height L or more. The rotator 249 adsorbs the developer G adsorbed on the outer peripheral surface of the rotator 249 while rotating in the direction of arrow D, and conveys the developer G into the replenishing port 250.

  Here, the toner T in the developing device 24 is attracted to the carrier CA mainly by the Coulomb force proportional to the charge amount of the developing device 24 and the van der Waals force acting near the surface of the carrier CA. When the amount of the toner T in the supply chamber 244 increases, the apparent volume of the developer G in the supply chamber 244 is the actual increase amount of the developer G even though the amount of the carrier CA is the same. It seems to be larger than. That is, when the amount of the toner T increases, the height L becomes higher than the increased volume of the toner T. Considering such properties, there is a correlation between the upper surface of the developer G in the stirring chamber 246 and the amount of toner T.

  The height L corresponds to the height when the developer G in the developing device 24 is the upper limit of the set toner density range. The height L is not a concept of the distance from the bottom surface to the top surface of the supply chamber 244 but a concept for specifying a relative position in relation to the rotating body 249. The height L is an example of a predetermined height.

  Further, as shown in FIG. 4, when the upper surface of the developer G in the supply chamber 244 is lower than the height L, the developer G is not adsorbed on the outer peripheral surface of the rotating body 249 in the adsorption region A1. It has become. In other words, the rotating body 249 is arranged so that the developer G is not adsorbed on the outer peripheral surface of the rotating body 249 when the upper surface of the developer G in the supply chamber 244 is lower than the height L. The rotating body 249 rotates while adsorbing the toner T in the replenishing port 250 to the carrier CA adsorbing to the outer peripheral surface thereof, and conveys the toner G to the fall area A2 (see FIG. 4). ). The lower side of the drop area A2 is a supply chamber 244. As a result, the rotator 249 conveys the toner T that has contacted in the replenishing port 250 to the drop area A2.

  Here, as shown in FIG. 4, the suction region A <b> 1 is a region where the outer peripheral surface of the rotating body 249 moves in the fourth quadrant of the orthogonal coordinate system described above. Further, the fall area A2 is an area where the outer peripheral surface of the rotating body 249 moves in the third quadrant of the orthogonal coordinate system described above, as shown in FIG.

  As described above, the N-pole magnetic member 249B and the S-pole magnetic member 249A are arranged on the inner peripheral surface side of the rotating body 249 (see FIG. 4). Then, a bundle of magnetic lines (magnetic field) from the N-pole magnetic member 249B to the S-pole magnetic member 249A is formed around the rotating body 249 (not shown). By this magnetic field, the developer G adsorbed in the adsorption region A1 is moved to the replenishing port 250 while being held by the rotating body 249. On the other hand, in the fall area A2, the force acting on the developer G conveyed by the rotating body 249 is set so that gravity is dominant over the magnetic force.

<< Operation of First Embodiment >>
Next, the effect | action of this Embodiment is demonstrated based on drawing.

  6 and 7 are diagrams illustrating the operation (state) of the developing device 24 according to the present embodiment. FIG. 6 shows a state in which the upper surface of the developer G in the supply chamber 244 is lower than the height L. FIG. 7 shows a state in which the upper surface of the developer G in the supply chamber 244 is higher than the height L.

  When the developing operation by the developing device 24 is started in the state of FIG. 6, the developing roll 242 is rotated in the direction of arrow E by the motor (see FIG. 6). As the developing roll 242 rotates, the supply member 243, the stirring member 245, and the rotating body 249 are also rotated in the directions of the arrow C, the arrow B, and the arrow D, respectively. The electrostatic latent image formed on the outer peripheral surface of the rotating photosensitive drum 21 is developed as a toner image by the toner T supplied from the developing roll 242. As a result, the developing device 24 consumes an amount of toner T corresponding to the developed toner image.

  In the meantime, the developer G that has been transported through the supply chamber 244 without being supplied to the developing roll 242 flows into the agitating chamber 246 through the opening 252A and is sent into the agitating chamber 246, between the supplying chamber 243 and the agitating chamber 246. Circulated.

  In addition, the rotating body 249 that rotates in the direction of arrow D rotates while being in contact with the toner T accumulated in the region facing the replenishing port 250. The toner T that contacts the replenishing port 250 is attached to the outer peripheral surface of the rotator 249 that passes through the region facing the replenishing port 250 via the developer G adsorbed on the outer peripheral surface. . The toner T adhering to the outer peripheral surface of the rotator 249 is regulated by the downstream side wall portion 250B of the replenishing port 250 and is conveyed to the drop area A2 while being rotated around by the rotator 249. The toner T transported to the fall area A2 mainly follows gravity and falls into the supply chamber 244 together with the carrier CA. As a result, the toner T conveyed from the replenishing port 250 is replenished. In the above description, the toner T that has been in contact with the replenishment port 250 is described as being attached via the developer G adsorbed on the outer peripheral surface of the rotating body 249, but without the developer G, In some cases, the rotating body 249 may be directly attached to the outer peripheral surface of the rotating body 249 and conveyed.

  Next, a case where the total amount of toner T consumed as a result of the developing operation is smaller than the total amount of toner T replenished from the replenishing port 250 will be described. In this case, the amount of the developer G in the supply chamber 244 is larger than that before the developing operation (the state of FIG. 6), and the upper surface of the developer G in the stirring chamber 246 may be higher than the height L. Obtain (see FIG. 7).

  When the upper surface of the developer G in the supply chamber 244 reaches the height L, the developer G in the supply chamber 244 is attracted by the magnetic force formed by the magnetic members 249A and 249B in the adsorption region A1 ( (See FIG. 7). And it is adsorbed by the outer peripheral surface of the rotary body 249, and is further conveyed in the replenishing port 250 (refer FIG. 7). A part of the developer G conveyed into the replenishing port 250 is adsorbed by the rotating body 249, is regulated by the downstream side wall portion 250B of the replenishing port 250, and is conveyed to the fall area A2 together with the rotating body 249. Dropped into the supply chamber 244. On the other hand, the remaining developer G conveyed into the replenishing port 250 is restricted in movement by the downstream side wall portion 250 </ b> B and stays in the replenishing port 250.

  As long as the upper surface of the developer G in the supply chamber 244 is not less than the height L (see FIG. 7), the toner T in the replenishing port 250 is rotated by the developer G retained in the replenishing port 250. Adhesion to the outer peripheral surface of 249 is inhibited. That is, the replenishment of the toner T into the supply chamber 244 in the refill port 250 is restricted.

  Further, when the developing operation is performed in this state (the state of FIG. 7) and the upper surface of the developer G in the supply chamber 244 becomes lower than the height L (the state of FIG. 6), the developer G in the supply chamber 244 is , It is no longer adsorbed in the adsorption region A1. Then, since the developer G in the supply chamber 244 is not conveyed into the replenishing port 250, the developer G that has previously stayed in the replenishing port 250 is gradually added to the replenishing port 250 by the rotating body 249. It is conveyed from the inside to the fall area A2. Thereafter, as the developer G staying in the replenishing port 250 is reduced from the replenishing port 250, the amount of toner T in which the toner T in the replenishing port 250 is gradually conveyed by the outer peripheral surface of the rotating body 249 is reduced. Will be increased. In this way, the toner T in the replenishing port 250 is replenished into the supply chamber 244.

  According to the developing device 24 of the present embodiment, when the upper surface of the developer G in the supply chamber 244 is equal to or higher than the height L (in the case of FIG. 7) as compared with the case where the rotating body of this configuration is not provided. Even if the physical quantity of the toner T in the room is not measured, excessive replenishment of the toner T is suppressed.

  Further, according to the image forming apparatus 10 of the present embodiment, the image forming failure caused by the excessive replenishment of the toner T compared to the case where the developing device constituting the image forming apparatus does not have the rotating body of the present configuration. Is suppressed.

  Further, according to the developing device 24 of the present embodiment, the toner T is replenished with a simple structure as compared with the case where the rotating body does not convey the toner T.

  Further, according to the developing device 24 of the present embodiment, the upper surface of the developer G in the supply chamber 244 is lower than the height L as compared with the case where the rotating body of this configuration is not provided (in the case of FIG. 6). ) The toner T is replenished to the height L without measuring the physical quantity of the toner T in the supply chamber 244.

  That is, in the developing device 24 according to the present embodiment, the physical amount of the toner T is not measured, and the developer T 24 in the developing device 24 is based on the correlation between the upper surface of the developer G in the supply chamber 244 and the amount of the toner T. The amount of toner T to be replenished is adjusted autonomously.

  Therefore, according to the developing device 24 of the present embodiment, the amount of toner T replenished in the developing device 24 is autonomously adjusted as compared with the case where the rotating body of this configuration is not provided.

  In other words, a measuring instrument (sensor) for measuring the physical quantity of the toner T and a configuration for attaching the measuring instrument are not required. Therefore, according to the developing device 24 of the present embodiment, the number of parts of the developing device is reduced as compared with the case where the rotating body of this configuration is not provided.

  The rotating body 249 is rotationally driven by a motor that transmits power to the developing roll 242. Therefore, according to the developing device 24 of the present embodiment, the number of parts of the developing device can be reduced as compared with a case where a motor for rotationally driving the rotating body is provided.

  Further, according to the image forming apparatus 10 of the present embodiment, the toner T can be increased to the height L without measuring the physical quantity of the toner T in the supply chamber 244 as compared with the case where the rotating body of this configuration is not provided. Can be replenished.

  Further, according to the developing device 24 of the present embodiment, the toner T conveyed from the replenishing port 250 is dropped to the suction area A1 as compared with the case where the suction area and the drop area are not set to different areas. It is suppressed. As a result, the suction region A1 is not easily affected by the drop of the toner T.

  Further, the rotating body 249 is disposed on the second chamber 244B as shown in FIG. As a result, according to the developing device 24 of the present embodiment, the upper surface of the toner T supplied to the developing roll 242 due to the replenishment of the toner T, compared to the case where the rotating body is disposed on the first chamber. Fluctuations are suppressed.

  The rotator 249 is disposed in a portion of the supply chamber 244 in the conveyance direction of the developer G, outside the developing region of the developing roller 242 and upstream of the stirring chamber 246. As a result, according to the developing device 24 of the present embodiment, the toner T is insufficiently stirred as compared with the case where the developing roller 24 is disposed outside the developing region of the developing roll and on the downstream side of the stirring chamber. The development failure due to the is suppressed.

  Further, the rotating body 249 is arranged above the supply chamber 244 as shown in FIG. The developer G in the supply chamber 244 is conveyed by the supply member 243, whereas the developer G in the stirring chamber 246 is stirred by the stirring member 245. That is, the upper surface of the developer G in the stirring chamber 246 is greatly shaken compared to the upper surface of the developer G in the supply chamber 244. In other words, since the upper surface of the developer in the supply chamber 244 is less swayed than the upper surface of the developer G in the stirring chamber 246, the height L of the developer G is less likely to sway.

  Therefore, according to the developing device 24 of the present embodiment, the amount of toner T to be replenished in the developing device 24 as compared with the case where the rotating body is arranged not above the supply chamber but above the stirring chamber. Is accurately adjusted.

  Further, as shown in FIG. 5, in the developing device 24, it is difficult to arrange the rotating body 249 above the stirring chamber 246. That is, when the supply chamber is formed above the stirring chamber (directly above or obliquely above), it is difficult to arrange the rotating body above the stirring chamber.

  On the other hand, the developing device 24 according to the present embodiment has a simple structure as compared with the case where the supply chamber is formed above the stirring chamber and the rotating body is disposed above the stirring chamber. A rotating body or a replenishing port can be arranged.

<Second Embodiment>
Next, an example of the second embodiment will be described with reference to FIG. Hereinafter, a description will be given centering on differences from the first embodiment. Note that the same parts (parts and the like) as those of the above-described embodiment will be described using the same reference numerals for the same parts and the like.

  FIG. 8 is a schematic diagram (cross-sectional view) showing an example of the developing device 324 of the present embodiment. The developing device 324 is different from the developing device 24 of the first embodiment in that it includes a magnetic member 249C.

  As shown in FIG. 8, the rotating body 249 of the developing device 324 is an area on the inner peripheral surface side of the rotating body 249 and is upstream of the rotating body 249 in the rotation direction with respect to the drop area A2 with the rotating body 249 interposed therebetween. A magnetic member 249C is disposed in a region facing the. The magnetic member 249C has N pole magnetism. As described above, since the N-pole magnetic member 249C is arranged, the magnetic field formed around the rotating body 249 is different from that of the developing device 24 of the first embodiment.

  Specifically, not only the magnetic lines of force from the N-pole magnetic member 249B but also magnetic lines of force from the N-pole magnetic member 249C are formed on the S-pole magnetic member 249A (not shown). Accordingly, in the fall region A2, the developer G is easily separated by the combined magnetic field of the N-pole magnetic member 249B and the N-pole magnetic member 249C.

  Further, a part of the magnetic lines of force extending from the N-pole magnetic member 249C to the S-pole magnetic member 249A is an area on the outer peripheral surface side of the rotating body 229 and is formed so as to pass around the adsorption area A1. That is, by arranging the N-pole magnetic member 249C on the inner peripheral surface side of the rotator 249, the magnetic field around the adsorption region A1 becomes stronger.

Therefore, according to the developing device 324 of the present embodiment, the magnetic member is disposed in an area on the inner peripheral surface side of the rotator that is opposed to the upstream side in the rotation direction of the rotator with respect to the drop area with the rotator interposed therebetween. Compared to the case where is not disposed, the developer G is more likely to fall in the fall region A2.
Further, according to the developing device 324 of the present embodiment, the magnetic member is disposed in an area on the inner peripheral surface side of the rotating body, which is opposed to the upstream side in the rotation direction of the rotating body with respect to the falling area with the rotating body interposed therebetween. The developer G is more easily adsorbed in the adsorption region A1 as compared with the case where is not arranged.
Other operations are the same as those in the first embodiment.

<Third Embodiment>
Next, an example of the third embodiment will be described with reference to FIGS. Hereinafter, a description will be given centering on differences from the first and second embodiments. Note that the same parts (parts and the like) as those of the above-described embodiment will be described using the same reference numerals for the same parts and the like.

  FIG. 9 is a schematic diagram (cross-sectional view) showing a configuration of the developing device 424 according to the third embodiment viewed from the upper surface side. FIG. 10 is a schematic diagram (cross-sectional view) showing a configuration of the developing device 424 as viewed from the front side. The supply chamber 444 of the developing device 424 includes a first chamber 444A that stores the supply member 243 and a third chamber 444B that stores the developer G overflowing from the first chamber 444A. Here, the supply chamber 444 is an example of a storage chamber.

  As shown in FIG. 9, the third chamber 444B is formed on the opposite side of the first chamber 444A across the wall portion 446C when viewed from the apparatus depth direction. The rotating body 249 is arranged so as to be directly above the third chamber 444B. Further, as shown in FIG. 10, the third chamber 444 </ b> B is formed so as to straddle a part of the developing area I in the developing roll 242 and the outside of the developing area I when viewed from the apparatus width direction.

  In the developing device 424, when the developer G in the first chamber 444A exceeds the upper surface of the wall portion 446C, the developer G in the first chamber 444A overflows into the third chamber 444B and is accommodated. . Then, the developer G that overflows and is accommodated in the third chamber 444B passes through an opening 252A formed in a wall portion 252 (not shown) between the stirring chamber 246 and the third chamber 444B, and passes through the third chamber. 444B is fed into the stirring chamber 246. Then, the developer G overflowing from the first chamber 444A passes through the third chamber 444B, and is upstream of the developer G in the transport direction of the developer G by the supply member 243 in the first chamber 444A via the stirring chamber 246. It is returned to and is circulated. The opening 252A has a slit shape with a width of about 1 mm (see FIG. 9).

  When the upper surface of the developer G stored in the third chamber 444B reaches a height L1 or more, the rotating body 249 that moves around the third chamber 444B moves the developer G stored in the third chamber 444B. Is adsorbed in the adsorption area A1 and conveyed to the inside of the replenishing port 250. (See FIG. 9). Here, the height L1 is an example of a predetermined height.

  Further, the rotator 249 retains the developer G conveyed in the replenishing port 250 in the replenishing port 250. As a result, the conveyance of the toner T in the replenishing port 250 by the rotating body 249 is restricted.

  Thereafter, when the developer G in the first chamber 444A is consumed, the upper surface of the developer G in the first chamber 444A becomes lower than the upper surface of the wall portion 444C. Accordingly, the developer G in the first chamber 444A does not overflow into the third chamber 444B. At the same time, the rotator 249 continues to transport the developer G in the third chamber 444B into the replenishing port 250, so that the upper surface of the developer G in the third chamber 444B becomes lower than the height L1. As a result, since the developer G in the third chamber 444B is not conveyed into the replenishing port 250, the developer G that has previously accumulated in the replenishing port 250 is gradually replenished by the rotating body 249. It is conveyed from the mouth 250 to the drop area A2. Thereafter, as the developer G staying in the replenishing port 250 is reduced from the replenishing port 250, the amount of toner T in which the toner T in the replenishing port 250 is gradually conveyed by the outer peripheral surface of the rotating body 249 is reduced. Will be increased. In this way, the toner T in the replenishing port 250 is replenished into the first chamber 446A.

  As described above, in the developing device 424, when the upper surface of the developer G in the first chamber 444A increases to the height of the upper surface of the wall portion 444C, the developer G in the first chamber 444A overflows into the third chamber 444B. Be contained. That is, the upper surface of the developer G in the first chamber 444A is unlikely to accumulate beyond the height of the upper surface of the wall portion 444C. In other words, the developer G in the first chamber 444A corresponds to this height. It is hard to exceed the amount to be. Then, the developer G in the first chamber 444A is stably supplied to the developing roll 242.

  Therefore, according to the developing device 424 of the present embodiment, the fluctuation in the height of the upper surface of the developer G is reduced as compared with the case where the rotating body is not disposed directly above the third chamber.

  In the developing device 424, the rotator 249 is disposed directly above the third chamber 444B, not the first chamber 444A in which the supply member 243 is accommodated (see FIGS. 9 and 10). The third chamber 444B is further away from the developing roller 242 than the first chamber 444A. That is, the amount of toner T replenished in the developing device 24 is autonomously adjusted using the third chamber 444B.

  Therefore, according to the developing device 424 of the present embodiment, development failure due to toner replenishment is suppressed as compared with the case where the rotating body is not disposed directly above the third chamber.

  Note that the third chamber 444B is formed so as to straddle a part of the developing area I in the developing roll 242 and the outside of the developing area I when viewed from the direction orthogonal to the own axis direction of the developing roll 242 ( The third chamber may be formed corresponding to the inside of the development region I (referred to as a modified example). In the case of this modification, the toner T replenished from the rotating body is not immediately supplied from the supply member to the developing roll.

Therefore, according to the developing device 424 of the present embodiment, the upper surface of the toner T supplied to the developing roll 242 caused by the replenishment of the toner T is compared with the case where the rotating body is disposed on the first chamber. Variation is suppressed.
Other operations are the same as those in the first or second embodiment.

  In this embodiment, the third chamber 444B is formed so as to straddle a part of the developing area I on the developing roll 242 and the outside of the developing area I when viewed from a direction orthogonal to the own axis direction of the developing roll 242. However, the third chamber 444B may be formed outside the development region I (see FIG. 10).

<Fourth embodiment>
Next, an example of the fourth embodiment will be described with reference to FIGS. Hereinafter, a description will be given centering on differences from the first to third embodiments. Note that the same parts (parts and the like) as those of the above-described embodiment will be described using the same reference numerals for the same parts and the like.

  FIG. 11 is a schematic diagram (cross-sectional view) showing a configuration of the developing device 524 according to the fourth embodiment viewed from the front side. FIG. 12 is a schematic diagram (cross-sectional view) showing a configuration of the developing device 524 according to the fourth embodiment viewed from the side.

  In the developing device 524, as shown in FIG. 11, the rotating member 249 is a part of the developing roller 242 that extends in the own axis direction, and is seen from the direction orthogonal to the own axis of the developing member. In the portion located outside the developing area. Further, the replenishment port 250 is one end side in the own axial direction of the developing roll 242 and is opposed to the upper side of the non-developing area J (see FIG. 12). In the developing device 524, the non-developing area J of the developing roll 242 has the function of the rotating body 249.

  Here, when the developing device 524 is viewed from the front side, the rotation center of the developing roll 242 is the center O1, the imaginary line in the device width direction passing through the center O1 is the X1 axis, and the imaginary line in the device height direction passing through the center O1. Is the Y1 axis. The positive direction of the X1 axis is the right side in the apparatus width direction, and the positive direction of the Y1 axis is the upper side in the apparatus height direction.

  As shown in FIG. 11, a magnetic member 249 </ b> D is disposed in a partial region on the inner peripheral surface side of the rotating body 249. Further, the magnetic member 249D has a long shape extending over the entire area of the developing roller 242 in its own axis direction. Further, the magnetic member 249D has N pole magnetism.

  As shown in FIG. 11, the magnetic member 249B is disposed on the inner peripheral surface side of the developing roll 242 so as to straddle the first quadrant and the fourth quadrant of the orthogonal coordinate system formed by the X1 axis and the Y1 axis. Has been. The magnetic member 249D is disposed on the inner peripheral surface side of the developing roll 242 so as to straddle the second quadrant and the third quadrant of the orthogonal coordinate system. The outer peripheral surface of the photosensitive drum 21 is opposed to the opposite side of the magnetic member 249D across the developing roll 242.

According to the developing device 524 of the present embodiment, the number of parts is reduced as compared with the case where the rotating body is not formed in a part extending in the own axis direction of the developing roll.
Other operations are the same as those in the first to third embodiments.

<Fifth embodiment>
Next, an example of the fifth embodiment will be described. Hereinafter, a description will be given centering on differences from the first to fourth embodiments. Note that the same parts (parts and the like) as those of the above-described embodiment will be described using the same reference numerals for the same parts and the like.

  The fifth embodiment includes any one of the developing devices 24, 324, 424, and 524 described in the first to fourth embodiments and the photosensitive drum 21, and is integrated with the image forming apparatus main body. The process cartridge 652 can be replaced (not shown). Here, the process cartridge 652 is an example of an assembly.

  If the process cartridge 652 of this embodiment is used, a measuring instrument (sensor) for measuring the physical quantity of the toner T and a configuration for attaching the measuring instrument to the process cartridge 652 and the image forming apparatus main body are not required.

Therefore, according to the process cartridge 652 of the present embodiment, the number of parts of the assembly including the developing device in which the toner T is replenished from the replenishing port is reduced as compared with the case where this configuration is not provided.
Further, according to the process cartridge 652 of the present embodiment, development defects due to excessive replenishment of toner are suppressed as compared with the case where the present configuration is not provided.
Other operations are the same as those in the first to fifth embodiments.

  As described above, the present invention has been described in detail with respect to specific embodiments. However, the present invention is not limited to the above-described embodiments, and various other embodiments are within the scope of the present invention. Is possible.

  For example, although the rotating body 249 has been described as a cylindrical shape, a belt that is wound around a driving roll and a driven roll and can be moved around may be used.

  Further, the magnetic member 249A disposed on the inner peripheral surface side of the rotating body 249 is disposed so as to face the region in the replenishing port 250 with the rotating body 249 interposed therebetween. Alternatively, the region outside the replenishing port 250 may be arranged so as to protrude and face each other.

  In addition, the magnetic member 249A on the inner peripheral surface side of the rotating body 249 is disposed so as to face the region in the replenishing port 250 with the rotating body 249 interposed therebetween, but all or part of the magnetic member 249A is disposed. The rotating body 249 may be disposed downstream of the replenishing port 250 in the rotation direction.

  The replenishing port 250 faces the outer peripheral surface of the rotating body 249 while contacting the toner T in the first quadrant and the second quadrant of the orthogonal coordinate system formed by the X axis and the Y axis. did. However, the replenishing port 250 is in contact with the rotating body 249 at an arbitrary position downstream of the suction area A1 and upstream of the falling area A2 in the rotational direction of the rotating body 249, while contacting the toner T. It only needs to be opposite.

  In addition, although the linear groove portion along the own axis direction is formed on the outer peripheral surface of the rotating body 249, the developer G or the toner T is conveyed to the outer peripheral surface subjected to blasting or the like. Anything is possible.

  The supply member 243 and the stirring member 245 are formed upward in the apparatus height direction (see FIGS. 4, 9, 11, etc.), but if the rotating body 249 is disposed above the supply member 243. The supply member 243 and the stirring member 245 may be formed side by side in the apparatus width direction.

  Further, although the stirring chamber 246 is connected to the toner cartridge through the replenishing port 250 and the replenishing path, the stirring chamber 246 may be connected to the toner cartridge only through the replenishing port 250.

  In addition, although the rotating body 249 is arranged along the own axis direction of the stirring member 245 (see FIG. 4), the rotating body 249 may be arranged not along the own axis direction of the stirring member 245.

10 Image forming apparatus 21 Photosensitive drum (an example of an image carrier)
22 Charger (example of charging device)
23 Exposure device (an example of a latent image forming device)
24, 324, 424, 524 Developing device 30 Transfer device 31 Transfer belt (an example of a transfer device)
33 Primary transfer roll (an example of a transfer device)
242 Developing roll (an example of a developing member)
243 supply member (an example of a supply unit)
244 Supply room (an example of a storage room)
244E, 444F Wall part (an example of an accommodating part)
249 Rotating body 250 Refill port 652 Process cartridge (an example of an assembly)
A1 Adsorption area A2 Falling area CA Carrier G Developers L and L1 Defined height P Medium T Toner

Claims (8)

A supply portion for supplying the developer to the developing member while conveying the developer including toner and a carrier in its own axial direction, and a storage portion for supplying the toner from above through a replenishing port;
When the upper surface of the developer provided above the storage chamber is opposed to the replenishing port and is transported in the supply chamber is higher than a predetermined height, while rotating about its own axis, A rotating body that adsorbs the developer, conveys the developer into the replenishing port, and retains the developer in the replenishing port;
A developing device comprising: When the upper surface of the developer in the storage chamber is lower than the predetermined height, the rotating body conveys the toner in the replenishing port to the fall area while rotating about its own axis.
The developing device according to claim 1. The rotating body conveys the toner in the replenishing port to a falling area upstream of the rotating body in the rotation direction with respect to an adsorption area that adsorbs the developer in the storage chamber.
The developing device according to claim 2. The housing chamber is formed outside the developing region of the developing member when viewed from a direction perpendicular to the first chamber of the developing member and the own axis of the developing member, and the developing flowed from the first chamber A second chamber through which the agent passes before being returned to the upstream side in the transport direction by the supply unit in the first chamber via a circulation path,
The rotating body is arranged to be directly above the second chamber;
The developing device according to claim 2 or 3. The supply chamber is formed on the opposite side of the developing member with respect to the first chamber accommodating the supply portion and the first chamber as viewed from the axial direction of the developing member, and overflows from the first chamber. A third chamber through which the developer passes before being returned to the upstream side in the transport direction by the supply unit in the first chamber via a circulation path;
Including
The rotating body is arranged to be directly above the third chamber.
The developing device according to claim 2 or 3. The rotating body is a part that extends in the own axis direction of the developing member, and is configured by a portion that is located outside the developing region of the developing member when viewed from a direction orthogonal to the own axis of the developing member. ing,
The developing device according to claim 1. An image carrier on which a latent image is formed;
The developing device according to any one of claims 1 to 6, wherein a latent image formed on the outer peripheral surface of the image carrier is developed as a toner image;
Including
An assembly assembled so as to be interchangeable with the image forming apparatus main body. An image carrier,
A charging device for charging the outer peripheral surface of the image carrier;
A latent image forming device that forms a latent image on the outer peripheral surface of the image carrier charged by the charging device;
The developing device according to claim 1, wherein the latent image is developed as a toner image.
A transfer device for transferring the toner image to a transfer target;
An image forming apparatus.

Images