JP2018045012A - Developing device and image forming apparatus including the same - Google Patents

Abstract

A developing device capable of efficiently collecting toner accumulated on a toner receiving member. A developing device includes a developing roller, a toner supply roller, a regulating blade, a casing, a toner receiving support member, a toner receiving member, and a vibration generator. The toner receiving and supporting member is disposed in the casing, and faces the developing roller or the toner supply roller between the regulating blade and the image carrier. The toner receiving member has a toner receiving surface that is disposed along the longitudinal direction of the toner receiving support member and that receives the toner dropped from the developing roller. The toner receiving support member is swingably supported by the casing in a direction in which a gradient of a toner receiving surface from the image carrier to the toner supply roller changes. [Selection diagram] FIG.

Description

  The present invention relates to a developing device that supplies a developer to an image carrier and an electrophotographic image forming apparatus including the developing device.

  An electrophotographic image forming apparatus irradiates a peripheral surface of an image carrier (photosensitive drum) with light based on image information read from an original image or image information transmitted from an external device such as a computer. An electrostatic latent image is formed, toner is supplied from the developing device to the electrostatic latent image to form a toner image, and then the toner image is transferred to a sheet. The paper after the transfer process is subjected to a toner image fixing process and then discharged to the outside.

  By the way, in recent years, in the image forming apparatus, the configuration of the apparatus becomes complicated with the progress of color printing and high-speed processing, and the toner stirring member in the developing device is forced to rotate at high speed to cope with high-speed processing. . In particular, in a development method using a two-component developer including a magnetic carrier and a toner and using a magnetic roller (toner supply roller) that carries the developer and a development roller that carries only the toner, the development roller and the magnetic roller In the opposite portion, only the toner is carried on the developing roller by the magnetic brush formed on the magnetic roller, and the toner that has not been used for development is peeled off from the developing roller. Therefore, toner scattering is likely to occur in the vicinity of the facing portion between the developing roller and the magnetic roller, and the toner floating in the developing device accumulates around the earbrush blade (regulating blade), and the accumulated toner aggregates. If the toner adheres to the developing roller, the toner may be dropped and an image defect may occur.

  Therefore, for example, Patent Document 1 discloses a developing device that uses a two-component developer including a magnetic carrier and a toner and uses a magnetic roller that supports the developer and a developing roller that supports only the toner. Development provided with a toner receiving support member facing the roller, a toner receiving member that is disposed along the longitudinal direction of the toner receiving support member and that receives toner falling from the developing roller, and a vibration generating means that vibrates the toner receiving member An apparatus is disclosed.

JP 2012-208469 A

  The toner deposited on the toner receiving member contains a lot of toner external additives, and the charging ability is reduced due to deterioration, so that the fluidity is deteriorated. In particular, in the case of a toner having low heat resistance, the accumulated toner may be solidified due to a temperature rise around the developing device. In addition, the fluidity of the toner changes depending on the usage environment of the image forming apparatus, the toner consumption amount in the developing device, and the like. Therefore, there is a problem that a sufficient toner recovery effect cannot be obtained by merely vibrating the toner receiving member as in Patent Document 1.

  In view of the above problems, an object of the present invention is to provide a developing device that can efficiently collect toner accumulated on a toner receiving member.

  In order to achieve the above object, a first configuration of the present invention includes a developing roller, a toner supply roller, a regulating blade, a casing, a toner receiving support member, a toner receiving member, and a vibration generating device. Development device. The developing roller is disposed to face the image carrier on which the electrostatic latent image is formed, and supplies toner to the image carrier in a region facing the image carrier. The toner supply roller is disposed to face the developing roller, and supplies toner to the developing roller in a region facing the developing roller. The regulating blade is disposed to face the toner supply roller at a predetermined interval. The casing houses a developing roller, a toner supply roller, and a regulating blade. The toner receiving support member is disposed in the casing and faces the developing roller or the toner supply roller between the regulating blade and the image carrier. The toner receiving member has a toner receiving surface that is disposed along the longitudinal direction of the toner receiving support member and receives toner falling from the developing roller. The vibration generator vibrates the toner receiving member. The toner receiving support member is supported to be swingable in a direction in which the gradient of the toner receiving surface from the image carrier side toward the toner supply roller side changes with respect to the casing.

  According to the first configuration of the present invention, since the toner receiving support member can swing in the direction in which the gradient of the toner receiving surface from the image carrier side toward the toner supply roller side changes, the vibration of the vibration generating device is vibrated. It is not absorbed by the cutting blade or developer container. As a result, the toner receiving member is subjected to the vibration of the toner receiving support member in addition to the vibration directly transmitted from the vibration generating device, so that the toner deposited on the toner receiving member can be efficiently shaken off. Therefore, even when the toner having low heat resistance is used, or even when the fluidity of the toner is lowered due to the usage environment of the image forming apparatus or the toner consumption in the developing device, the toner deposited on the toner receiving member is efficiently used. It can be shaken off well, and the occurrence of image defects due to toner drop can be effectively suppressed.

Schematic configuration diagram of a color printer 100 equipped with the developing devices 3a to 3d of the present invention Side sectional view of the developing device 3a according to the first embodiment of the present invention mounted on the color printer 100. The perspective view which looked at the toner receiving support member 35 used for the image development apparatus 3a of 1st Embodiment from the inner side of the developing container 20. FIG. The perspective view of the support member main body 36 which comprises the toner receiving support member 35 The perspective view which looked at the toner receiving member 37 which comprises the toner receiving support member 35 from the back surface side The perspective view which shows the internal structure of the vibration generator 40 with which the toner receiving member 37 is mounted | worn. Front view of vibration motor 43 Side view of the vibration motor 43 as seen from the side of the vibration weight 50 FIG. 4 is a side cross-sectional view around the toner receiving support member 35 of the developing device 3a, showing a cross section near the vibration motor 43; 9 is a partially enlarged view of the toner receiving support member 35 in FIG. Side surface sectional drawing which shows the support structure of the toner receiving support member 35 in the image development apparatus 3a of 1st Embodiment. The figure which shows the state which the rocking | fluctuation axis | shaft 61 side of the support member main body 36 rock | fluctuated upward from the state of FIG. Side sectional view showing electrical connection between the toner supply roller 30 and the toner receiving member 37 in the developing device 3a of the first embodiment. Schematic side view of the roller contact / separation mechanism 70 used in the developing device 3a according to the second embodiment of the present invention. Schematic view of the relationship between the roller contact / separation mechanism 70, the developing roller 31, and the photosensitive drum 1a in the developing device 3a of the second embodiment viewed from the axial direction FIG. 6 is a side cross-sectional view showing a support structure of a toner receiving support member 35 in a developing device 3a of a second embodiment, showing a state in which a developing roller 31 is arranged at a developing position. FIG. 9 is a side cross-sectional view illustrating a support structure of a toner receiving support member 35 in a developing device 3a according to a second embodiment, and illustrates a state where a developing roller 31 is disposed at a retracted position. A block diagram showing a control path of a color printer 100 including developing devices 3a to 3d according to the second embodiment. Side sectional view showing the developing device 3a of the present invention in which the arrangement of the toner supply roller 30 and the developing roller 31 is reversed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an image forming apparatus on which developing devices 3a to 3d of the present invention are mounted. Here, a tandem color printer is shown. In the main body of the color printer 100, four image forming portions Pa, Pb, Pc, and Pd are sequentially arranged from the upstream side in the transport direction (the right side in FIG. 1). These image forming portions Pa to Pd are provided corresponding to images of four different colors (cyan, magenta, yellow, and black), and cyan, magenta, and yellow are respectively performed by charging, exposure, development, and transfer processes. And a black image are sequentially formed.

  These image forming portions Pa to Pd are provided with photosensitive drums 1a, 1b, 1c and 1d for carrying visible images (toner images) of the respective colors, and further rotate clockwise in FIG. An intermediate transfer belt 8 is provided adjacent to each of the image forming portions Pa to Pd.

  When image data is input from a host device such as a personal computer, first, the surfaces of the photosensitive drums 1a to 1d are uniformly charged by the chargers 2a to 2d. Next, light is irradiated by the exposure device 5 according to the image data, and electrostatic latent images corresponding to the image data are formed on the respective photosensitive drums 1a to 1d. The developing devices 3a to 3d are filled with a predetermined amount of a two-component developer (hereinafter, also simply referred to as a developer) containing toners of cyan, magenta, yellow, and black by toner containers 4a to 4d. The toner in the developer is supplied onto the photosensitive drums 1a to 1d by 3a to 3d and electrostatically adheres. Thereby, a toner image corresponding to the electrostatic latent image formed by exposure from the exposure device 5 is formed.

  The primary transfer rollers 6a to 6d apply an electric field at a predetermined transfer voltage between the primary transfer rollers 6a to 6d and the photosensitive drums 1a to 1d, and cyan, magenta, yellow, and yellow on the photosensitive drums 1a to 1d. A black toner image is primarily transferred onto the intermediate transfer belt 8. Toner remaining on the surfaces of the photosensitive drums 1a to 1d after the primary transfer is removed by the cleaning devices 7a to 7d.

  The transfer paper P onto which the toner image is transferred is housed in a paper cassette 16 disposed in the lower part of the color printer 100, and the transfer paper P passes through a paper feed roller 12a and a registration roller pair 12b at a predetermined timing. Then, the sheet is conveyed to the nip portion (secondary transfer nip portion) between the secondary transfer roller 9 provided adjacent to the intermediate transfer belt 8 and the intermediate transfer belt 8. The transfer sheet P on which the toner image is secondarily transferred is conveyed to the fixing unit 13.

  The transfer paper P conveyed to the fixing unit 13 is heated and pressed by the fixing roller pair 13a to fix the toner image on the surface of the transfer paper P, and a predetermined full-color image is formed. The transfer paper P on which the full-color image is formed is discharged to the discharge tray 17 by the discharge roller pair 15 as it is (or after being distributed to the reverse conveyance path 18 by the branching unit 14 and the image is formed on both sides).

  FIG. 2 is a side sectional view of the developing device 3a according to the first embodiment of the present invention mounted on the color printer 100. FIG. 2 shows a state viewed from the back side of FIG. 1, and the arrangement of each member in the developing device 3a is opposite to that in FIG. Further, in the following description, the developing device 3a disposed in the image forming unit Pa of FIG. 1 is illustrated, but the configuration of the developing devices 3b to 3d disposed in the image forming units Pb to Pd is basically the same. Therefore, explanation is omitted.

  As shown in FIG. 2, the developing device 3a includes a developing container (casing) 20 in which a two-component developer (hereinafter simply referred to as a developer) composed of toner and a magnetic carrier is stored. The partition wall 20a is divided into an agitating and conveying chamber 21 and a supply and conveying chamber 22. In the agitating / conveying chamber 21 and the supply / conveying chamber 22, the agitating / conveying screw 25 a for supplying toner (positively charged toner) supplied from the toner container 4 a (see FIG. 1) with the carrier, agitating and charging, and the supplying and conveying Each screw 25b is rotatably arranged.

  Then, the developer is agitated by the agitating / conveying screw 25a and the supply / conveying screw 25b and conveyed in the axial direction (perpendicular to the paper surface of FIG. 2) to pass through the developer (not shown) formed at both ends of the partition wall 20a. It circulates between the stirring and conveying chamber 21 and the supply and conveying chamber 22 through the path. That is, a developer circulation path is formed in the developer container 20 by the agitating / conveying chamber 21, the supply / conveying chamber 22, and the developer passage.

  The developing container 20 extends obliquely upward to the right in FIG. 2. A toner supply roller 30 (developer carrying member) is disposed above the supply / conveying screw 25 b in the developing container 20. A developing roller 31 is disposed diagonally upward. The developing roller 31 faces the photosensitive drum 1a (see FIG. 1) on the opening side (the right side in FIG. 2) of the developing container 20, and the toner supply roller 30 and the developing roller 31 are shown in FIG. 2 rotates counterclockwise.

  A toner concentration sensor 28 is disposed in the agitating and conveying chamber 21 so as to face the agitating and conveying screw 25a. The toner concentration sensor 28 detects the ratio (T / C) of the toner to the carrier in the developer. For example, a magnetic permeability sensor that detects the magnetic permeability of the developer in the developing container 20 is used. In the present embodiment, the toner density sensor 28 detects the magnetic permeability of the developer, and a voltage value corresponding to the detection result is output to a control unit (not shown) described later. The toner density is determined from the output value of the toner density sensor 28. The control unit transmits a control signal to a toner replenishing motor (not shown) according to the determined toner concentration, and a predetermined amount of toner is transferred from the toner container 4a to the stirring and conveying chamber 21 via a toner replenishing port (not shown). The toner is replenished.

  The toner supply roller 30 is composed of a non-magnetic rotating sleeve that rotates counterclockwise in FIG. 2 and a fixed magnet body having a plurality of magnetic poles contained in the rotating sleeve.

  The developing roller 31 includes a cylindrical developing sleeve that rotates counterclockwise in FIG. 2 and a developing roller side magnetic pole that is fixed in the developing sleeve. It faces with a predetermined gap at the facing position (facing position). The developing roller side magnetic pole has a different polarity from the opposing magnetic pole (main pole) of the fixed magnet body.

  Further, a spike cutting blade 33 is attached to the developing container 20 along the longitudinal direction of the toner supply roller 30 (a direction perpendicular to the paper surface of FIG. 2), and the spike cutting blade 33 rotates in the rotation direction of the toner supply roller 30. In the counterclockwise direction in FIG. 2, the developing roller 31 and the toner supply roller 30 are positioned on the upstream side. A slight gap (gap) is formed between the tip of the ear cutting blade 33 and the surface of the toner supply roller 30.

  A DC voltage (hereinafter referred to as Vslv (DC)) and an AC voltage (hereinafter referred to as Vslv (AC)) are applied to the developing roller 31, and a DC voltage (hereinafter referred to as Vmag (DC)) is applied to the toner supply roller 30. ) And an alternating voltage (hereinafter referred to as Vmag (AC)). These DC voltage and AC voltage are applied to the developing roller 31 and the toner supply roller 30 via the bias control circuit 80 (see FIG. 18) from the developing bias power source 82 (see FIG. 13).

  As described above, the developer is agitated by the agitating / conveying screw 25a and the supply / conveying screw 25b, and the toner is charged by circulating through the agitating / conveying chamber 21 and the supplying / conveying chamber 22 in the developing container 20, and the supply / conveying screw 25b. The developer is conveyed to the toner supply roller 30. Then, a magnetic brush (not shown) is formed on the toner supply roller 30. After the layer thickness of the magnetic brush on the toner supply roller 30 is regulated by the earbrushing blade 33, the toner supply roller 30 and the developing roller 31 are separated. A thin toner layer is formed on the developing roller 31 by a potential difference ΔV between Vmag (DC) applied to the toner supply roller 30 and Vslv (DC) applied to the developing roller 31 and a magnetic field.

  The toner thin layer formed on the developing roller 31 by contact with the magnetic brush on the toner supply roller 30 is conveyed to a facing portion (facing region) between the photosensitive drum 1 a and the developing roller 31 by the rotation of the developing roller 31. The Since Vslv (DC) and Vslv (AC) are applied to the developing roller 31, the toner flies due to a potential difference with the photosensitive drum 1a, and the electrostatic latent image on the photosensitive drum 1a is developed. .

  Remaining toner that is not used for development is conveyed again to the opposite portion between the developing roller 31 and the toner supply roller 30 and is collected by the magnetic brush on the toner supply roller 30. The magnetic brush is peeled off from the toner supply roller 30 at the same polarity portion of the fixed magnet body, and then falls into the supply conveyance chamber 22.

  Thereafter, a predetermined amount of toner is replenished from a toner replenishing port (not shown) based on the detection result of the toner concentration sensor 28, and is uniformed again at an appropriate toner concentration while circulating through the supply transport chamber 22 and the stirring transport chamber 21. It becomes a charged two-component developer. This developer is again supplied onto the toner supply roller 30 by the supply / conveyance screw 25 b to form a magnetic brush, and is conveyed to the ear cutting blade 33.

  A toner receiving and supporting member 35 having a triangular cross-section projecting inward of the developing container 20 is provided in the vicinity of the developing roller 31 on the right side wall in FIG. As shown in FIG. 2, the toner receiving support member 35 is disposed along the longitudinal direction of the developing container 20 (the direction perpendicular to the paper surface of FIG. 2). A wall portion that faces the developing roller 31 and is inclined downward from the developing roller 31 toward the toner supply roller 30 is configured. On the upper surface of the toner receiving support member 35, a toner receiving member 37 is attached along the longitudinal direction for receiving the toner that is peeled off from the developing roller 31 and falls.

  3 is a perspective view of the toner receiving support member 35 used in the developing devices 3a to 3d as viewed from the inside of the developing container 20 (left side in FIG. 2). FIG. 4 is a support member main body constituting the toner receiving support member 35. FIG. 5 is a perspective view of the toner receiving member 37 constituting the toner receiving support member 35 as viewed from the inside of the toner receiving support member 35. 4 shows a state in which the support member main body 36 is viewed from the mounting direction of the toner receiving member 37.

  The toner receiving support member 35 is attached to a resin supporting member main body 36, a sheet metal toner receiving member 37 that is swingably supported by the supporting member main body 36, and a substantially central portion in the longitudinal direction of the toner receiving member 37. Vibration generator 40 to be operated. The support member main body 36 is formed with a storage portion 36a in which the vibration generating device 40 is stored when the toner receiving member 37 is mounted. As will be described later, the support member main body 36 is swingably supported with respect to the developing container 20.

  A film member 44 is provided on the upper end of the support member main body 36. The film member 44 extends in the longitudinal direction (left and right direction in FIG. 3) of the support member main body 36 so that the front end portion is in contact with the surface of the photosensitive drum 1a, and is in the developing container 20 (see FIG. 2). It has a function of shielding the toner from leaking outside.

  The toner receiving member 37 has a bent shape in which a bent portion 37a is formed along the longitudinal direction, the toner receiving surface 37b facing the developing roller 31 (see FIG. 2) with the bent portion 37a interposed therebetween, and the toner supply roller 30. And a substantially vertical toner dropping surface 37c facing the surface. A holding portion 39 having a pair of holding claws 39 a that hold the vibration generating device 40 is formed at a substantially central portion in the longitudinal direction of the toner receiving member 37. A substrate 45 on which a circuit for controlling driving of the vibration motor 43 (see FIG. 6) and electronic components (not shown) are mounted is fixed to the vibration generator 40 by screws 46.

  Sheet members 41 a and 41 b are attached to the surface of the toner receiving member 37 (the surface facing the developing roller 31 or the toner supply roller 30). The sheet members 41 a and 41 b are formed of a material that prevents toner from adhering to the toner receiving member 37 in order to suppress toner adhesion to the toner receiving member 37. Examples of the material of the sheet members 41a and 41b include a fluororesin sheet.

  The sheet member 41 a is affixed so as to cover the surface of the toner receiving member 37 (toner dropping surface 37 c) including the boundary between the support member main body 36 and the toner receiving member 37 on the ear cutting blade 33 side. The sheet member 41b covers the entire area of the toner receiving surface 37b including the boundary between the support member main body 36 and the toner receiving member 37 on the film member 44 side, the engaging portion 38, and the holding portion 39 (see FIG. 5). It is pasted. The sheet members 41 a and 41 b prevent toner from adhering to the toner receiving surface 37 b and the toner dropping surface 37 c, and the toner from the boundary between the support member main body 36 and the toner receiving member 37 to the inside of the toner receiving support member 35. The malfunction of the vibration motor 43 due to the entry or toner entry is prevented.

  FIG. 6 is a perspective view of the vibration generator 40. 6 shows a state in which the substrate 45 (see FIG. 5) is removed from the motor mounting holder 42 so that the inside of the vibration generator 40 can be seen. The vibration generator 40 includes a motor mounting holder 42 and a vibration motor 43, and the motor mounting holder 42 is formed with a motor holding portion 42 a for holding the vibration motor 43 and a screw hole 42 b for fastening a screw 46. A vibration weight 50 is fixed to the output shaft 43 a of the vibration motor 43. When the vibration generating device 40 is attached to the toner receiving member 37, the output shaft 43 a of the vibration motor 43 is fixed along the longitudinal direction of the toner receiving member 37. A lead wire (not shown) for supplying power to the vibration motor 43 is connected to the motor mounting holder 42.

  FIG. 7 is a front view of the vibration motor 43, and FIG. 8 is a side view of the vibration motor 43 as viewed from the side of the vibration weight 50. When seen from the direction of the output shaft 43a of the vibration motor 43 (the right direction in FIG. 7), the vibration weight 50 has a cam shape in which a notch 50a is formed in a part of the disk as shown in FIG. Thus, the shape is asymmetric with respect to the output shaft 43a. When the output shaft 43a rotates at a speed higher than a predetermined speed, the centrifugal force acting on the notch 50a is smaller than that of the other portions, so that an uneven centrifugal force is applied to the vibration weight 50. As the centrifugal force is transmitted to the output shaft 43a, the vibration motor 43 vibrates. The shape of the vibration weight 50 is not limited to a cam shape, and may be an arbitrary shape that shifts the center of gravity with respect to the output shaft 43a.

  FIG. 9 is a side sectional view showing a cross section (cross section taken along the line XX ′ in FIG. 3) of the toner receiving support member 35 used in the developing device 3a of the present embodiment in the vicinity of the vibration motor 43, and FIG. 3 is a partially enlarged view of a toner receiving support member 35. FIG.

  As shown in FIGS. 9 and 10, only the edge 37d on the toner supply roller 30 side of the toner receiving member 37 is in contact with the support member main body 36, and the edge 37e on the opposite side (photosensitive drum 1a side) is It is a free end. The substantially central portion of the toner receiving surface 37b in the width direction (left-right direction in FIG. 9) is supported by the support member body 36 via the vibration generator 40. Thereby, the toner receiving member 37 is configured to be swingable with the end edge 37d as a fulcrum. Further, the vibration motor 43 is disposed so that the output shaft 43 a is substantially parallel to the longitudinal direction of the toner receiving member 37.

  The toner receiving member 37 is inclined such that the toner receiving surface 37b facing the developing roller 31 is inclined upward from the toner supply roller 30 side toward the photosensitive drum 1a side, and the toner falling surface 37c facing the toner supply roller 30. Are arranged so as to be substantially vertical.

  By rotating the output shaft 43a of the vibration motor 43 at high speed (for example, about 10,000 rpm) during non-image formation, the vibration weight 50 also rotates at high speed together with the output shaft 43a. At this time, since an uneven centrifugal force is applied to the vibration weight 50, the vibration generator 40 including the vibration motor 43 and the motor mounting holder 42 vibrates via the output shaft 43a. The toner receiving member 37 to which the vibration generating device 40 is attached also vibrates. Specifically, the toner receiving surface 37b of the toner receiving member 37 vibrates so that the amplitude becomes larger toward the end edge 37e with the end edge 37d as a fulcrum.

  Due to the vibration of the toner receiving surface 37b, as shown in FIG. 10, the toner T deposited on the toner receiving surface 37b slides downward (in the direction of the white arrow in FIG. 10) along the inclination of the toner receiving surface 37b, and is substantially vertical. The toner falls freely into a region R sandwiched between the toner dropping surface 37c and the toner supply roller 30. A portion of the toner that has fallen into the region R passes through the gap between the ear cutting blade 33 and the toner supply roller 30 and falls into the supply conveyance chamber 22 as it is.

  Further, in the present embodiment, in order to return the toner that has fallen to the region R to the supply conveyance chamber 22, the developing roller 31 and the toner supply roller 30 are rotated in the opposite direction to the image formation in the non-image formation (clockwise direction in FIG. 9). Rotate (reverse). By rotating the toner supply roller 30 in the reverse direction, the toner that has fallen into the region R and accumulated on the tip of the ear cutting blade 33 is scraped off by the magnetic brush of the toner supply roller 30, and is rotated around the surface of the toner supply roller 30. After passing through the gap between the toner supply roller 30 and the ear cutting blade 33 and being peeled off from the toner supply roller 30 at the same polarity part of the fixed magnet body, the toner is forcibly returned to the supply conveyance chamber 22.

  When the developing roller 31 and the toner supply roller 30 are rotated in the reverse direction, the magnetic force of the magnetic pole (regulatory pole) of the fixed magnet body facing the ear cutting blade 33 so that the ears of the magnetic brush formed on the toner supply roller 30 become long. By adjusting the arrangement, the effect of scraping off the toner deposited on the tip of the ear cutting blade 33 is enhanced. Further, when the developing roller 31 and the toner supply roller 30 are rotated in the reverse direction, the agitating and conveying screw 25a and the supply and conveying screw 25b are also rotated in the reverse direction, so that the developer in the developing container 20 overflows from the toner supply port or the developing container 20 In some cases, the developer may be biased and noise of the toner density sensor 28 may be generated. Therefore, after the developing roller 31 and the toner supply roller 30 are rotated in reverse, it is preferable to rotate the developing roller 31 and the toner supply roller 30 in order for a predetermined time.

  When the toner receiving member 37 is vibrated, the toner supply roller 30 and the developing roller 31 can be rotated (forward rotation) in the same direction as the image formation (counterclockwise direction in FIG. 9). By rotating the toner supply roller 30 forward, a part of the toner dropped from the toner receiving surface 37 b to the region R adheres to the magnetic brush on the toner supply roller 30. The remaining toner that has not adhered to the magnetic brush on the toner supply roller 30 passes through the gap between the toner supply roller 30 and the ear cutting blade 33 and falls into the supply conveyance chamber 22.

  In the present embodiment, the output shaft 43a of the vibration motor 43 is such that the outer peripheral surface of the output shaft 43a facing the toner receiving member 37 is a fulcrum (end edge 37d) from the free end (end edge 37e) of the toner receiving member 37. In the direction of moving toward (counterclockwise in FIG. 10). By rotating the output shaft 43a in this direction, the toner receiving member 37 vibrates so as to move the toner accumulated on the toner receiving surface 37b from the end edge 37e side to the end edge 37d side.

  On the other hand, when the output shaft 43a is rotated in the reverse direction (clockwise direction in FIG. 10), the toner is moved up from the edge 37d side to the edge 37e side by the vibration of the toner receiving member 37. Therefore, the toner deposited on the toner receiving surface 37b does not slide down. Therefore, by rotating the output shaft 43a of the vibration motor 43 as in the present embodiment, the toner accumulated on the toner receiving surface 37b can be effectively dropped to the region R along a descending gradient.

  The timing at which the toner receiving member 37 is vibrated may be set every time the printing operation is completed, or may be a predetermined time such as when the number of printed sheets reaches a predetermined number or when the temperature in the developing device 3a becomes equal to or higher than a predetermined number. It may be performed at the timing. The timing for vibrating the toner receiving member 37 and the timing for rotating the developing roller 31 and the toner supply roller 30 in reverse (or forward) may be the same or different. Further, by vibrating the toner receiving member 37 every time the predetermined number of printed sheets is reached, the vibration of the toner receiving member 37 is automatically executed according to the number of printed sheets. Therefore, it is not necessary for the user himself to manually set the vibration of the toner receiving member 37, and it is possible to avoid setting mistakes, forgetting to set, or unnecessary vibration.

  11 and 12 are side cross-sectional views showing the support structure of the toner receiving support member 35 in the developing device 3a of this embodiment. As shown in FIG. 11, a support shaft 60a and a swing shaft 61 are formed at both ends of the support member main body 36 in the longitudinal direction (direction perpendicular to the paper surface of FIG. 11). 11 and 12, only the support shaft 60a and the swing shaft 61 on one end side in the longitudinal direction are illustrated. The support shaft 60 on the toner supply roller 30 side (left side in FIG. 11) is rotatably engaged with a bearing hole 62 formed in the developing container 20. The swing shaft 61 on the side opposite to the toner supply roller 30 (right side in FIG. 11) is slidably engaged with a long-sliding slide hole 63 formed in the developing container 20. That is, the support member main body 36 can swing in the vertical direction on the side opposite to the toner supply roller 30 (on the side of the swinging shaft 61) at the swinging fulcrum constituted by the support shaft 60 and the bearing hole 62 on the toner supply roller 30 side. It is supported by.

  In the conventional configuration, the bottom surface of the support member main body 36 is fixed to the upper surface of the spike cutting blade 33, and the back surface of the support member main body 36 is fixed to the developing container 20. Therefore, the vibration of the vibration generating device 40 is absorbed by the earbrush blade 33 and the developing container 20, and the vibration of the toner receiving member 37 is also suppressed, so that the toner with reduced fluidity deposited on the toner receiving member 37 can be sufficiently obtained. I couldn't shake it.

  According to the configuration of the present embodiment, since the support member main body 36 is not fixed to the ear cutting blade 33 or the developing container 20, when the vibration generating device 40 is vibrated, the support member main body 36 has a structure as shown in FIG. It vibrates so that the side opposite to the toner supply roller 30 jumps up. That is, the vibration of the vibration generating device 40 is not absorbed by the ear cutting blade 33 or the developing container 20.

  As a result, the vibration of the support member main body 36 is added to the toner receiving member 37 supported on the upper surface of the support member main body 36 in addition to the vibration directly transmitted from the vibration generating device 40. Accordingly, the amplitude of the toner receiving member 37 is increased, and the toner having lowered fluidity can be efficiently shaken off.

  FIG. 13 is a side sectional view showing an electrical connection between the toner supply roller 30 and the toner receiving member 37 in the developing device 3a of the present embodiment. In the present embodiment, the toner receiving member 37 is electrically connected to the developing bias power supply 65 via the support shaft 60 and has the same potential as the toner supply roller 30.

  By setting the toner supply roller 30 and the toner receiving member 37 to the same potential, current leakage between the metal toner receiving member 37 and the toner supply roller 30 can be prevented. In addition, since a bias having the same polarity (here, positive polarity) as that of the toner is applied to the toner supply roller 30, a bias having the same polarity as that of the toner is also applied to the toner receiving member 37. Accordingly, the toner does not electrostatically adhere to the toner receiving member 37, and toner accumulation on the toner receiving member 37 can be suppressed.

  In addition, the toner supply roller 30 and the toner receiving member 37 can be simply configured by taking an electrical contact between the toner supply roller 30 and the toner receiving member 37 with a support shaft 60 that is a swinging fulcrum of the toner receiving support member 35. Can be electrically connected.

  In this embodiment, the support shaft 60 and the swing shaft 61 are provided on the toner receiving support member 35 side (support member main body 36 side), and the bearing hole 62 and the sliding hole 63 are formed on the developing container 20 side. A bearing hole 62 and a sliding hole 63 may be formed on the receiving support member 35 side (support member main body 36 side), and a support shaft 60 and a swing shaft 61 may be provided on the developing container 20 side.

  FIG. 14 is a schematic side view of the roller contact / separation mechanism 70 used in the developing device 3a according to the second embodiment of the present invention. FIG. 15 illustrates the roller contact / separation mechanism 70, the development roller 31, and the photosensitive drum 1a. It is the schematic which looked at the relationship from the axial direction (right direction of FIG. 14). A mechanism for approaching and retracting the developing roller 31 from the photosensitive drums 1a to 1d by the roller contact / separation mechanism 70 will be described with reference to FIGS. Here, the roller contact / separation mechanism 70 of the developing device 3a will be described, but the description is omitted because the same applies to the developing devices 3b to 3d.

  The roller contact / separation mechanism 70 brings the developing roller 31 into contact with the photosensitive drum 1a so that the developing roller 31 and the photosensitive drum 1a do not rub against each other when the developing device 3a is inserted into or pulled out from the main body of the color printer 100. Alternatively, they are separated. The roller contact / separation mechanism 70 includes arm members 72a and 72b, a shaft member 73 that contacts the upper surfaces of the arm members 72a and 72b, a first coil spring 74, a bearing member 75, and a second coil spring 76. .

  The shaft member 73 is a rod-shaped member that is formed of a material having a predetermined rigidity and is disposed along the longitudinal direction of the developing device 3a. The shaft member 73 is disposed so as to be movable in the axial direction (arrow AA ′ direction). Yes. The shaft member 73 has a pressing portion 73 a that protrudes from the developing container 20, and protrudes downward from the outer peripheral surface of the shaft member 73 at positions corresponding to the arm members 72 a and 72 b in the vicinity of both end portions of the shaft member 73. Two ribs 73b are formed. The rib 73b has a fin shape in a side view in which the amount of protrusion from the outer peripheral surface gradually changes along the axial direction of the shaft member 73.

  In addition, a hook-shaped engaging portion 73 c that engages with one end of the first coil spring 74 is formed at a substantially central portion in the longitudinal direction of the shaft member 73.

  The first coil spring 74 is a tension spring and has one end engaged with the engaging portion 73c and the other end fixed to the developing container 20, and the pressing portion 73a of the shaft member 73 is free from the front side of the developing device 3a. The shaft member 73 is biased forward in the axial direction (in the direction of arrow A ′) so as to protrude. The bearing member 75 is formed integrally with the arm members 72a and 72b, and functions as a link member that receives both ends of the rotating shafts 30a and 31a of the toner supply roller 30 and the developing roller 31 and connects the rollers 30 and 31. The toner supply roller 30 swings integrally in the direction of the arrow BB ′ about the rotation shaft 30a.

  Accordingly, when the bearing member 75 swings around the rotation shaft 30a, the developing roller 31 swings around the toner supply roller 30 together with the bearing member 75 to approach or retract from the photosensitive drum 1a. A second coil spring 76 is fixed to the bearing member 75, and the bearing member 75 is urged by the second coil spring 76 in a direction that swings in the direction of arrow B.

  As shown in FIGS. 14 and 15, in a state where the pressing portion 73a of the shaft member 73 protrudes from the developing device 3a, the arm members 72a and 72b ride on the rib 73b and are pressed downward, and the developing roller 31 is photosensitive. It is in a position retracted from the body drum 1a. When the pressing portion 73a is pushed into the developing device 3a from this state, the arm member 72a, 72b is detached from the rib 73b by the shaft member 73 moving in the axial direction back side (arrow A direction). The bearing members 75 connected to the arm members 72 a and 72 b swing in the direction of arrow B about the rotation shaft 30 a by the urging force of the second coil spring 76. As a result, the developing roller 31 is disposed at a position (developing position) close to the photosensitive drum 1a.

  On the other hand, when the pressing of the pressing portion 73a is released, the shaft member 73 moves forward in the axial direction (in the direction of arrow A ′) by the urging force of the first coil spring 74, so that each arm member 72a, 72b rides on the rib 73b, The arm members 72a and 72b swing around the rotation shaft 30a in the direction of the arrow B ′. Since the bearing member 75 together with the arm members 72a and 72b swings in the direction of the arrow B ′ against the biasing force of the second coil spring 76, the developing roller 31 is separated from the photosensitive drum 1a (retracted position). Placed in.

  16 and 17 are side cross-sectional views showing the support structure of the toner receiving support member 35 in the developing device 3a of this embodiment. As shown in FIG. 16, support shafts 60 are formed on the toner supply roller 30 side (left side in FIG. 16) at both ends of the support member main body 36 in the longitudinal direction (direction perpendicular to the paper surface in FIG. 16). The support shaft 60 is fixed to the bearing member 75. FIG. 16 shows a state in which the developing roller 31 is disposed at the developing position. Also in the present embodiment, the vibration of the vibration generating device 40 is not absorbed by the ear cutting blade 33 or the developing container 20 as in the first embodiment, and therefore the toner receiving member 37 supported on the upper surface of the support member main body 36 includes In addition to the vibration directly transmitted from the vibration generator 40, the vibration of the support member main body 36 is added. Accordingly, the amplitude of the toner receiving member 37 is increased, and the toner having lowered fluidity can be efficiently shaken off.

  In addition, when the bearing member 75 is rotated in the arrow B ′ direction from the state of FIG. 16 and the developing roller 31 is disposed at the retracted position, the toner receiving support member 35 together with the bearing member 75 is also moved to the arrow B ′ as shown in FIG. Rotate in the direction. As a result, the inclination of the toner receiving member 37 from the photosensitive drum 1a side to the toner supply roller 30 side (from right to left in FIG. 17) becomes larger than that in FIG. Therefore, by vibrating the vibration generating device 40 in the state shown in FIG. 17 in which the developing roller 31 is separated from the photosensitive drum 1a, it is possible to efficiently shake off the toner having decreased fluidity accumulated on the toner receiving member 37. it can.

  Further, when the toner receiving support member 35 rotates together with the bearing member 75 in the direction of the arrow B ′, the toner receiving support member 35 (support member main body 36) is separated upward from the spike cutting blade 33. As a result, a gap G is formed between the ear cutting blade 33 and the toner receiving support member 35. A seal member 67 is disposed along the longitudinal direction between the spike cutting blade 33 and the toner receiving support member 35 so that the toner does not leak out of the developing container 20 from the gap G. The seal member 67 is formed of an elastic material such as sponge, and the seal member 67 is compressed in the state of FIG. 16 where the ear cutting blade 33 and the toner receiving support member 35 are in contact with each other. In the state shown in FIG. 17 where the ear cutting blade 33 and the toner receiving support member 35 are separated from each other, the seal member 67 expanded by the restoring force fills the gap G.

  FIG. 18 is a block diagram illustrating a control path of the color printer 100 including the developing devices 3a to 3d according to the second embodiment. In addition, since various controls of each part of the apparatus are performed when the color printer 100 is used, the control path of the entire color printer 100 becomes complicated. Therefore, here, a portion of the control path that is necessary for the implementation of the present invention will be mainly described.

  The bias control circuit 80 is connected to the charging bias power supply 81, the developing bias power supply 82, and the transfer bias power supply 83, and operates each of these power supplies in response to an output signal from the control unit 90. In accordance with a control signal from the control circuit 80, the charging bias power source 81 is applied to the charging roller in the charging devices 2a to 2d, and the developing bias power source 82 is applied to the toner supply roller 30 and the developing roller 31 in the developing devices 3a to 3d. Reference numeral 83 applies predetermined biases to the primary transfer rollers 6a to 6d and the secondary transfer roller 9, respectively.

  The image input unit 84 is a receiving unit that receives image data transmitted to the color printer 100 from a personal computer or the like. The image signal input from the image input unit 84 is converted into a digital signal and then sent to the temporary storage unit 94.

  The operation unit 85 is provided with a liquid crystal display unit 86 and LEDs 87 indicating various states, and displays the state of the color printer 100 and displays the image forming status and the number of copies to be printed. Various settings of the color printer 100 are performed from a printer driver of a personal computer.

  The in-machine temperature / humidity sensor 88 detects the temperature inside the color printer 100, particularly the temperature and humidity around the developing devices 3a to 3d, and is disposed in the vicinity of the image forming portions Pa to Pd.

  The control unit 90 includes a central processing unit (CPU) 91 as a central processing unit, a read only memory (ROM) 92 that is a read-only storage unit, a random access memory (RAM) 93 that is a readable / writable storage unit, A plurality of (two in this case) that transmit control signals to and receive input signals from the operation unit 70, temporarily storing image data and the like, a counter 95, and each device in the color printer 100. At least an I / F (interface) 96 is provided.

  The ROM 92 stores a control program for the color printer 100, data necessary for control, and the like that are not changed during use of the color printer 100. The RAM 93 stores necessary data generated during control of the color printer 100, data temporarily required for control of the color printer 100, and the like. The RAM 93 (or ROM 92) also stores a threshold value for the number of printed sheets that triggers execution of a toner collection mode described later. The temporary storage unit 94 temporarily stores an image signal input from the image input unit 84 and converted into a digital signal. The counter 95 counts the accumulated number of printed sheets.

  The control unit 90 transmits a control signal from the CPU 91 to the respective units and devices in the color printer 100 through the I / F 96. In addition, a signal indicating the state and an input signal are transmitted from each part or device to the CPU 91 through the I / F 96. Examples of each part and device controlled by the control unit 90 include the image forming units Pa to Pd, the vibration generating device 40, the roller contact / separation mechanism 70, the bias control circuit 80, and the image input unit 84.

  The color printer 100 vibrates the toner receiving member 37 in the developing devices 3a to 3d by the vibration generating device 40 during non-image formation, and shakes off the toner accumulated on the toner receiving member 37 to collect it in the supply conveyance chamber 22. The mode can be executed. Whether or not to execute the toner recovery mode is determined, for example, based on whether or not the cumulative number of printed sheets (or the cumulative driving time of the developing devices 3a to 3d) after the previous execution of the toner recovery mode has reached a predetermined value.

  As described above, when the developing roller 31 is disposed at the retracted position, the inclination of the toner receiving member 37 from the photosensitive drum 1a side to the toner supply roller 30 side becomes large. In this state, by vibrating the vibration generating device 40 and executing the toner recovery mode, the toner deposited on the toner receiving member 37 can be efficiently shaken off. However, when the toner collecting mode is executed by switching the developing roller 31 from the developing position to the retracted position using the roller contact / separation mechanism 70 and the operation of returning the developing roller 31 to the developing position again after the toner collecting mode is executed, the user's The waiting time becomes longer.

  On the other hand, the amount of floating toner generated in the developing device 3a varies depending on the usage environment of the image forming apparatus, the amount of toner consumed in the developing device, and the like. For example, when the printing rate of the formed image is high, the amount of toner consumed in the developing device increases, so that the amount of toner deposited on the toner receiving member also increases. Conversely, when the printing rate of the formed image is low, the amount of toner consumed in the developing device is reduced, and the amount of toner deposited on the toner receiving member is also reduced.

  Therefore, in the present embodiment, the control unit 90 generates the vibration in the first toner recovery mode in which the vibration generating device 40 is driven with the developing roller 31 placed at the developing position and the developing roller 31 placed at the retracted position. The second toner recovery mode for driving the device 40 can be selectively executed.

  For example, the control unit 90 executes the first toner recovery mode when the toner consumption amount in the developing devices 3a to 3d after execution of the previous toner recovery mode is equal to or less than a predetermined value, and causes the developing devices 3a to 3d to When the toner consumption exceeds a predetermined value, the second toner recovery mode is executed. Thus, when the toner consumption is small, it is determined that the amount of toner deposited on the toner receiving member 37 is small, and the first toner collection mode is executed with the developing roller 31 placed at the developing position. The waiting time required for the movement of can be shortened. On the other hand, when the amount of toner consumption is large, it is determined that the amount of toner deposited on the toner receiving member 37 is also large, and the second toner recovery mode is executed with the developing roller 31 placed at the retracted position. Can be shaken out sufficiently. That is, the execution frequency of the second toner recovery mode can be minimized.

  Note that the toner consumption is the cumulative printing rate since the previous execution of the toner collection mode, or the cumulative number of rotations of a toner replenishing motor (not shown) that replenishes the toner in the toner containers 4a to 4d to the developing devices 3a to 3d. Can be calculated based on

  Further, when the cumulative number of printed sheets reaches a predetermined value during continuous printing, the time for interrupting printing becomes longer when the second toner recovery mode is executed. Therefore, the first toner recovery mode that does not require the movement of the developing roller 31 is executed when the cumulative number of printed sheets reaches a predetermined number during continuous printing, and development is performed when the cumulative number of printed sheets reaches the predetermined number after completion of printing. A second toner recovery mode involving the movement of the roller 31 is executed. Thus, during continuous printing, the printing waiting time can be shortened as much as possible to give priority to printing efficiency, and after the completion of printing, the recovery of toner accumulated on the toner receiving member 37 can be given priority.

  Further, the first toner recovery mode is based on the toner density (T / C) in the developing devices 3 a to 3 d detected by the toner density sensor 28 and the in-machine temperature / humidity of the color printer 100 detected by the in-machine temperature / humidity sensor 88. And the second toner recovery mode can be selected. For example, when the toner density in the developing devices 3a to 3d is higher than a predetermined value, the amount of floating toner in the developing container 20 increases, so that the toner that accumulates on the toner receiving member 37 also increases. Therefore, the first toner recovery mode may be executed when the toner concentration is equal to or lower than the predetermined value, and the second toner recovery mode may be executed when the toner concentration exceeds the predetermined value.

  Further, since the fluidity of the toner decreases as the in-machine temperature / humidity increases, the first toner recovery mode is executed when the in-machine temperature / humidity is below a predetermined value, and the second toner recovery occurs when the in-machine temperature / humidity exceeds a predetermined value. Just execute the mode.

  In addition, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, the shape and configuration of the toner receiving support member 35 and the toner receiving member 37 shown in the above embodiments are merely examples, and are not particularly limited to the above embodiments. Can be set.

  In each of the above embodiments, the present invention uses a two-component developer, forms a magnetic brush on the toner supply roller 30, moves only the toner from the toner supply roller 30 to the development roller 31, The present invention is applied to the developing devices 3a to 3d for supplying toner to the photosensitive drums 1a to 1d. In addition, as shown in FIG. 19, the arrangement of the developing roller 31 and the toner supply roller 30 is reversed from the above embodiments. The toner is applied to the photosensitive drums 1a to 1d by a magnetic brush made of a two-component developer held on the surface of the developing roller 31 (in this configuration, a magnetic roller having the same configuration as the toner supply roller 30 in the above embodiments). On the surface of the toner supply roller 30 (in this configuration, the configuration is the same as that of the developing roller 31 in each of the above embodiments). Supplies to the developing roller 31 the toner is also applicable to a developing device for collecting the surplus toner of the developing roller 31 surface with a toner supply roller 30. Even in this configuration, it is possible to effectively suppress the toner dropped from the developing roller 31 from being accumulated around the regulating blade 33 facing the toner supply roller 30.

  The present invention can be used for an image forming apparatus including a developing device having a toner receiving member facing the developing roller between a region where the image carrier and the developing roller are opposed to each other and a regulating blade. By utilizing the present invention, it is possible to provide a developing device capable of efficiently collecting the deteriorated toner accumulated on the toner receiving member.

Pa to Pd Image forming section 1a to 1d Photosensitive drum (image carrier)
3a to 3d Developing device 4a to 4d Toner container 20 Developing container (casing)
30 Toner supply roller 31 Developing roller 33 Ear cutting blade (regulating blade)
35 Toner receiving support member 35a Tip portion 36 Support member main body 37 Toner receiving member 37a Bending portion 37b Toner receiving surface 37c Toner falling surface 40 Vibration generating device 41a, 41b Sheet member 60a Support shaft (fulcrum)
60b Oscillating shaft 61 Bearing hole (fulcrum)
63 Sliding hole 67 Seal member 70 Roller contact / separation mechanism 75 Bearing member 82 Development bias power supply (bias application device)
90 control unit 100 color printer (image forming apparatus)

Claims (11)

A developing roller that is disposed to face an image carrier on which an electrostatic latent image is formed, and that supplies toner to the image carrier in a region facing the image carrier;
A toner supply roller that is disposed to face the developing roller and supplies toner to the developing roller in a region facing the developing roller;
A regulating blade disposed opposite to the toner supply roller at a predetermined interval;
A casing that houses the developing roller, the toner supply roller, and the regulating blade;
A toner receiving support member disposed in the casing and facing the developing roller or the toner supply roller between the regulating blade and the image carrier;
A toner receiving member that has a toner receiving surface that is disposed along the longitudinal direction of the toner receiving support member so as to have a downward gradient from the image carrier side toward the toner supply roller side and that receives toner falling from the developing roller. When,
A vibration generator for vibrating the toner receiving member;
In a developing device comprising:
The developing device, wherein the toner receiving support member is supported to be swingable in a direction in which a gradient of the toner receiving surface from the image carrier side toward the toner supply roller side changes with respect to the casing.   2. The toner receiving support member according to claim 1, wherein an end on the side opposite to the toner supply roller is supported so as to be able to swing up and down with an end on the toner supply roller side as a fulcrum. Development device. The fulcrum is provided at both longitudinal ends of the toner receiving support member or at one end of the casing, and at both longitudinal ends of the toner receiving support member or at the other end of the casing. Bearing hole supported rotatably,
At the end of the toner receiving support member opposite to the toner supply roller, the longitudinal ends of the toner supply roller or one of the casings are provided with swinging shafts, and both ends of the toner supply roller in the longitudinal direction. 3. The developing device according to claim 2, further comprising: a slot-like sliding hole that is provided on the other side of the casing or the casing and that slidably engages with the swing shaft. A bias applying device for applying a bias to the toner supply roller;
The developing device according to claim 3, wherein the toner receiving member is held at the same potential as the toner supply roller by being electrically connected to the bias applying device via the fulcrum. A pair of bearing members that rotatably support both ends of the rotation shaft of the developing roller and swingable about the rotation shaft of the toner supply roller;
A roller contact / separation mechanism that selectively arranges the developing roller at either a developing position close to the image carrier or a retracted position away from the image carrier by swinging the bearing member;
The toner receiving support member is fixed to the bearing member, and when the developing roller is disposed at the retracted position, the gradient of the toner receiving surface from the image carrier side toward the toner supply roller side increases. The developing device according to claim 1, wherein the toner receiving support member swings.   In the state where the developing roller is disposed at the retracted position by the roller contact / separation mechanism at the time of non-image formation, the toner receiving member is vibrated by the vibration generating device to shake off the toner deposited on the toner receiving surface. The developing device according to claim 5. A seal member made of an elastic material is disposed between the toner receiving support member and the regulating blade,
The seal member is compressed by the pressing force of the toner receiving support member when the developing roller is disposed at the developing position, and the pressing force of the toner receiving support member is released when the developing roller is disposed at the retracted position. The developing device according to claim 5, wherein the seal member is expanded by a restoring force to fill a gap between the toner receiving support member and the regulating blade.   An image forming apparatus comprising the developing device according to claim 1. A developing device according to any one of claims 5 to 7,
A control unit for controlling driving of the developing device;
An image forming apparatus capable of executing a toner recovery mode in which the toner receiving member is vibrated by the vibration generating device during non-image formation to shake off the toner deposited on the toner receiving surface.
The controller executes a first toner recovery mode for executing the toner recovery mode with the developing roller disposed at the development position, and executes the toner recovery mode with the development roller disposed at the retracted position. An image forming apparatus capable of executing a second toner recovery mode.   The control unit executes the first toner recovery mode when the toner consumption amount in the developing device after execution of the toner recovery mode is not more than a predetermined value, and the toner consumption amount in the developing device is The image forming apparatus according to claim 9, wherein the second toner recovery mode is executed when a predetermined value is exceeded. The control unit executes the first toner recovery mode or the second toner recovery mode when the cumulative number of printed sheets after the previous execution of the toner recovery mode reaches a predetermined number.
The controller executes the first toner recovery mode when the cumulative number of printed sheets reaches a predetermined number during continuous printing, and the second toner when the cumulative number of printed sheets reaches the predetermined number after completion of printing. The image forming apparatus according to claim 9, wherein a collection mode is executed.

Images