JP2012003059A - Developing device and image-forming apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device capable of avoiding a temperature rise of a developer by cooling a drive part for rotating and driving a stirring member and a developing member, and an image-forming apparatus including the same.SOLUTION: A developing device 2 comprises: a second spiral 44 for stirring a developer; a second drive gear 56 for rotating the second spiral 44; a developing roller 20 for supplying the developer to a surface of a photoreceptor 11; and a third drive gear 57 for rotating the developing roller 20. Moreover, the device comprises: a storage box 51 configured by forming an inlet 51a which accommodates the second and third drive gears 56 and 57, supports a second and third rotation axes 44b and 20a in a rotatable manner and intakes air, and an outlet 51b for exhausting the air taken in; and a Sirocco fan 61 that is provided at the second rotation axis 44b in the storage box 51, intakes air from the inlet 51a into the storage box 51, and exhausts the air from the outlet 51b by passing through the inside of the storage box 51.

Description

  The present invention relates to a developing device used in an image forming apparatus such as a copying machine, a printer, a facsimile, or a composite machine using an electrophotographic system, and an image forming apparatus including the developing device, and in particular, a drive unit can be cooled. The present invention relates to a developing device and an image forming apparatus having the same.

  In an image forming apparatus such as a copying machine or a printer, the developer is stirred by a stirring member in a developer container that contains the developer, and the stirred developer is transported from the stirring member to the developing member. After the developer carried on the substrate is thinned with a blade, the developer is supplied to the image carrier. Thus, in the development process for visualizing the electrostatic latent image on the image carrier, friction between the developers due to agitation, friction due to contact between the developer and the blade, and further due to rotation of the agitation member and the development member Heat is generated by sliding friction and the temperature of the developing device rises.

  When the temperature of the developing device rises, there is a risk that the temperature of the developer will rise and the performance of the developer will deteriorate, and the fluidity of the developer will deteriorate in the developer container, and the developer will adhere to the blade and the developing member. As a result, development unevenness may occur and the development performance may be reduced.

  Therefore, in order to cool the developing device, in Patent Document 1, a large number of cooling fins are formed on the bottom surface of the developing container for containing the developer, and the cooling fins constitute a heat sink. As a result, the heat in the developing container generated by the stirring of the developer and the contact between the developer and the blade is released to the outside of the developing device by the heat sink.

JP 2007-226148 A (paragraphs [0078] and [0079], FIG. 2)

  As a factor of the temperature rise of the developing device, in addition to the stirring of the developer and the contact between the developer and the blade mentioned in the prior art, sliding friction between the rotating shaft of the stirring member and the developing member and its bearing, Further, there is heat generation due to friction of the drive unit such as friction caused by a drive gear that rotates the stirring member and the developing member. In recent years, with the increase in the speed of image forming apparatuses, the rotation speeds of the stirring member and the developing member have increased, and the heat generated by these drive units has further increased the temperature of the developing apparatus. However, the above-described prior art has a problem that it is difficult to suppress a temperature rise due to heat generated by the driving unit of the developing member and the stirring member.

  The present invention has been made to solve the above-described problems, and a developing device that cools a drive unit that rotationally drives a stirring member and a developing member to suppress a temperature rise of the developer and an image including the developing device. An object is to provide a forming apparatus.

  In order to achieve the above object, a developing device according to a first aspect of the present invention includes a stirrer that stirs a developer in a developer container, a stirrer gear that rotates the stirrer, and the stirrer and the stirrer gear connected to each other. An agitation rotating shaft, a developing member that supplies developer to the surface of the image carrier, a developing gear that forms a gear train with the agitation gear and rotates the developing member, and the developing member and the developing gear. A developing rotary shaft to be coupled, the stirring gear and the developing gear are accommodated to rotatably support the stirring rotary shaft and the developing rotary shaft, and an intake port for taking in air and an exhaust port for discharging the taken-in air A storage box formed in the storage box, and at least one rotation shaft of the agitation rotation shaft and the development rotation shaft in the storage box. It is characterized by comprising a blowing member for discharging the elaborate air from the exhaust port by passing within the storage box.

  According to a second aspect of the present invention, in the above developing device, the air blowing member is provided on a rotating shaft disposed in the vicinity of the air inlet and is disposed opposite to the air inlet.

  According to a third aspect of the present invention, in the above developing device, the air blowing member causes air to flow in the circumferential direction of the rotating shaft.

  According to a fourth aspect of the invention, there is provided an image forming apparatus equipped with the developing device having the above configuration.

  According to the first aspect of the present invention, when the agitating member and the developing member rotate in order to agitate the developer and supply the developer, the sliding friction is caused at the portion that rotatably supports (bearing) the agitating rotating shaft and the developing rotating shaft. Generates heat, and further generates heat due to friction at each meshing portion of the stirring gear and the developing gear. However, since air flows through the blowing member in the storage box, these heats are discharged together with the air flow from the exhaust port of the storage box, and the stirring rotation shaft, the development rotation shaft, the stirring gear, and the development gear are connected. By cooling, the temperature rise of the developer can be suppressed. Further, when the air blowing member is provided in the storage box, the apparatus can be reduced in size.

  Further, according to the second invention, the air blowing member is disposed in the vicinity of the intake port of the storage box, so that a large amount of external cold air can be taken in and distributed in the storage box, The development rotating shaft, the agitation gear, and the development gear can be efficiently cooled.

  According to the third aspect of the invention, since the air blowing member causes air to flow in the circumferential direction with respect to the rotating shaft, the stirring rotating shaft, the developing rotating shaft, the stirring gear, and the developing gear can be efficiently cooled. Moreover, it becomes possible to attach a ventilation member to a narrow space, and even if a ventilation member is accommodated with a stirring gear and a development gear in an accommodation box, there is no possibility that an accommodation box will enlarge.

  According to the fourth aspect of the invention, an image forming apparatus including a developing device that cools a driving unit that rotationally drives the agitating member and the developing member to suppress a temperature rise of the developer can be provided.

1 is a diagram schematically illustrating an image forming apparatus including a developing device according to an embodiment of the present invention. Sectional drawing which shows schematically the developing device which concerns on embodiment FIG. 1 is a plan view schematically showing a developing device according to an embodiment. Side surface sectional drawing which shows schematically the storage box which concerns on embodiment

  Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments. Further, the use of the invention and the terms shown here are not limited thereto.

  FIG. 1 is a diagram schematically illustrating an image forming apparatus including a developing device according to an embodiment of the present invention. The image forming apparatus 1 is a tandem type color printer, and the rotatable photoconductors 11a to 11d use an organic photoconductor (OPC photoconductor) as a photosensitive material for forming a photosensitive layer, and are black, yellow, cyan. , And magenta. Around each of the photoreceptors 11a to 11d, developing devices 2a to 2d, an exposure unit 12, chargers 13a to 13d, and cleaning devices 14a to 14d are disposed.

  The developing devices 2a to 2d are arranged to face the right sides of the photoconductors 11a to 11d, respectively, and supply toner to the photoconductors 11a to 11d. The chargers 13a to 13d are arranged on the upstream side of the developing devices 2a to 2d with respect to the rotation direction of the photosensitive member and opposed to the surfaces of the photosensitive members 11a to 11d, and uniformly charge the surfaces of the photosensitive members 11a to 11d. Let

  The exposure unit 12 scans and exposes each of the photoconductors 11a to 11d based on image data such as characters and patterns input from a personal computer or the like to an image input unit (not shown). The developing device 2a ~ 2d below. The exposure unit 12 is provided with a laser light source and a polygon mirror, and a reflection mirror and a lens are provided corresponding to each of the photoreceptors 11a to 11d. Laser light emitted from the laser light source is applied to the surfaces of the photoconductors 11a to 11d from the downstream side in the photoconductor rotation direction of the chargers 13a to 13d via the polygon mirror, the reflection mirror, and the lens. Electrostatic latent images are formed on the surfaces of the photoreceptors 11a to 11d by the irradiated laser light, and the electrostatic latent images are developed into toner images by the developing devices 2a to 2d.

  The endless intermediate transfer belt 17 is stretched around the tension roller 6, the driving roller 25, and the driven roller 27. The driving roller 25 is rotationally driven by a motor (not shown), and the intermediate transfer belt 17 is circulated and driven by the rotation of the driving roller 25.

  The photoreceptors 11a to 11d are arranged below the intermediate transfer belt 17 along the conveying direction (arrow direction in FIG. 1) so as to come into contact with the intermediate transfer belt 17. The primary transfer rollers 26a to 26d face the photoconductors 11a to 11d with the intermediate transfer belt 17 interposed therebetween, and press contact with the intermediate transfer belt 17 to form a primary transfer portion. In the primary transfer portion, the toner images on the photoconductors 11 a to 11 d are sequentially transferred to the intermediate transfer belt 17 at a predetermined timing with respect to the rotation of the intermediate transfer belt 17. As a result, a color toner image is formed on the surface of the intermediate transfer belt 17 by superposing toner images of four colors, cyan, magenta, yellow, and black.

  The secondary transfer roller 34 is opposed to the driving roller 25 with the intermediate transfer belt 17 interposed therebetween, and presses against the intermediate transfer belt 17 to form a secondary transfer portion. In this secondary transfer portion, the toner image on the surface of the intermediate transfer belt 17 is transferred to the paper P. After the transfer, the belt cleaning device 31 cleans the toner remaining on the intermediate transfer belt 17.

  A paper feed cassette 32 that stores paper P is disposed below the image forming apparatus 1, and a stack tray 35 that supplies manually fed paper is disposed to the right of the paper feed cassette 32. On the left side of the paper feed cassette 32, a first paper transport path 33 for transporting the paper P fed from the paper feed cassette 32 to the secondary transfer portion of the intermediate transfer belt 17 is disposed. Further, on the left side of the stack tray 35, a second paper transport path 36 for transporting paper fed from the stack tray 35 to the secondary transfer unit is disposed. Further, on the upper left side of the image forming apparatus 1, a fixing unit 18 that performs a fixing process on the sheet P on which an image is formed, and a third sheet transport that transports the sheet on which the fixing process has been performed to the sheet discharge unit 37. A path 39 is provided.

  The paper feed cassette 32 can be replenished by pulling it out of the apparatus (the front side of the paper surface in FIG. 1). The paper P stored therein is picked up by the pickup roller 33b and the separating roller 33a one by one. It is fed out to the first paper transport path 33 side.

  The first paper transport path 33 and the second paper transport path 36 merge before the registration roller 33c, and the registration roller 33c takes the timing of the image forming operation and the paper feeding operation on the intermediate transfer belt 17, The paper P is conveyed to the secondary transfer unit. The sheet P conveyed to the secondary transfer unit is secondarily transferred with the toner image on the intermediate transfer belt 17 by the secondary transfer roller 34 to which a bias potential is applied, and is conveyed to the fixing unit 18.

  The fixing unit 18 includes a fixing belt heated by a heater, a fixing roller in contact with the fixing belt, a pressure roller disposed in pressure contact with the fixing roller across the fixing belt, and the toner image is transferred. The fixing process is performed by heating and pressurizing the sheet P. After the toner image is fixed on the paper P by the fixing unit 18, the toner image is reversed by the fourth paper conveyance path 40 as necessary, and the toner image is secondarily transferred to the back surface of the paper P by the secondary transfer roller 34. Fixing is performed by the fixing unit 18. The paper P on which the toner image is fixed passes through the third paper conveyance path 39 and is discharged to the paper discharge portion 37 by the discharge roller 19a.

  FIG. 2 is a cross-sectional view showing a developing device used in the image forming apparatus 1 described above. In the following description, the configuration and operation of the developing device 2a corresponding to the photoconductor 11a shown in FIG. 1 will be described. However, the configuration and operation of the developing devices 2b to 2d are the same as those of the developing device 2a. Omitted, and symbols a to d indicating developing devices and photoreceptors of the respective colors are omitted.

  As shown in FIG. 2, the developing device 2 includes a developing roller 20, a magnetic roller 21, a regulating blade 24, a stirring member 42, a developing container 22, and the like.

  The developing container 22 constitutes the outline of the developing device 2, and is partitioned into a first transport path 22d and a second transport path 22c by a partitioning portion 22b at a lower portion thereof. The first transport path 22d and the second transport path 22c contain a developer composed of a carrier and toner. The developing container 22 holds the stirring member 42, the developing roller 20, and the magnetic roller 21. Further, the developing container 22 is formed with an opening 22 a that exposes the developing roller 20 toward the photoconductor 11.

  The developing roller 20 faces the photoconductor 11 and is disposed on the right side of the photoconductor 11 with a certain interval. Further, the developing roller 20 forms a developing area D for supplying toner to the photoconductor 11 at a facing position close to the photoconductor 11. The magnetic roller 21 is opposed to the developing roller 20 with a certain interval, and is disposed diagonally to the right of the developing roller 20. Further, the magnetic roller 21 supplies toner to the developing roller 20 at a facing position close to the developing roller 20. The stirring member 42 is disposed substantially below the magnetic roller 21. The regulating blade 24 is fixedly held on the developing container 22 obliquely to the left of the magnetic roller 21.

  The stirring member 42 is composed of two pieces, a first spiral 43 and a second spiral 44. A first spiral 43 is provided in the first conveyance path 22 d below the magnetic roller 21, and a second spiral 44 is provided in the second conveyance path 22 c adjacent to the right side of the first spiral 43.

  The first and second spirals 43 and 44 are rotated by a driving mechanism including a motor and a gear, which will be described later, and the developer is stirred by this rotation to charge the toner in the developer to a predetermined level. As a result, the toner is held on the carrier. Further, communication portions (not shown) are provided at both end portions in the longitudinal direction (front and back direction of the paper surface of FIG. 2) of the partition portion 22b that partitions the first transport path 22d and the second transport path 22c. When the two spiral 44 rotates, the charged developer is conveyed to the first spiral 43 from one communicating portion provided in the partition portion 22b, and the developer circulates in the first conveyance path 22d and the second conveyance path 22c. To do. Then, the developer is supplied from the first spiral 43 to the magnetic roller 21.

  The magnetic roller 21 includes a fixed shaft 21c, a magnetic pole member M, and a magnetic sleeve 21b. The magnetic roller 21 carries the developer stirred by the stirring member 42 and supplies only the toner to the developing roller 20 from the carried developer. In the magnetic pole member M, a plurality of magnets of different outer polarities formed in a sector shape are arranged in a predetermined order, and are fixed to the fixed shaft 21c by adhesion or the like. The fixed shaft 21c is supported by the developing container 22 in a non-rotatable manner with a predetermined gap between the magnetic pole member M and the magnetic sleeve 21b in the magnetic sleeve 21b. The magnetic sleeve 21b is rotated in the same direction as the developing roller 20 (clockwise direction in FIG. 2) by a driving mechanism including a motor and a gear, which will be described later, and a bias 48 in which the AC voltage 48b is superimposed on the DC voltage 48a is applied. The On the surface of the magnetic sleeve 21 b, the charged developer is carried by forming a magnetic brush by the magnetic force of the magnetic pole member M, and the magnetic brush is adjusted to a predetermined height by the regulating blade 24.

  When the magnetic sleeve 21b rotates, the magnetic brush is carried on the surface of the magnetic sleeve 21b by the magnetic pole member M and conveyed, and when it contacts the developing roller 20, only the magnetic brush toner is applied to the bias 48 applied to the magnetic sleeve 21b. Accordingly, the toner is supplied to the developing roller 20.

  The developing roller 20 includes a magnetic pole member 20b, a developing sleeve 20c formed in a cylindrical shape with a nonmagnetic metal material, a fixed shaft 20d, and the like.

  The fixed shaft 20d is supported by the developing container 22 so as not to rotate. A magnetic pole member 20b made of a magnet is fixed to the fixed shaft 20d at a position facing the magnetic roller 21 by a predetermined distance from the developing sleeve 20c by adhesion or the like, and the developing sleeve 20c is rotatably held. The developing sleeve 20c is rotated in an arrow direction (clockwise direction) in FIG. 2 by a driving mechanism including a motor and a gear, which will be described later. A developing bias 47 in which an AC voltage 47b is superimposed on a DC voltage 47a is applied to the developing sleeve 20c.

  When the developing sleeve 20c to which the developing bias 47 is applied is rotated in the clockwise direction in FIG. The toner thus discharged flies to the photoconductor 11. The flying toner sequentially adheres to the exposed portion on the photoconductor 11 rotating in the direction of arrow A (counterclockwise direction), and the electrostatic latent image on the photoconductor 11 is developed.

  Next, a drive mechanism for rotating the stirring member 42, the developing roller 20, and the magnetic roller 21 will be described with reference to FIGS. FIG. 3 is a plan view schematically showing the developing device, and FIG. 4 is a side sectional view schematically showing a storage box of the developing device. In FIG. 3, only the second spiral 44 is shown in the first and second spirals 43 and 44 of the stirring member 42.

  As shown in FIG. 3, a developing roller 20 and a magnetic roller 21, which are developing members, and first and second spirals 43 and 44 (agitating member 42, see FIG. 2) are disposed in the developing container 22. A storage box 51 is disposed on one side of the developing container 22. In the accommodation box 51, a plurality of drive gears 55 to 58 (see also FIG. 4) and a sirocco fan 61 as a blower member are disposed.

  The second spiral 44 is provided integrally with the second rotation shaft 44b and the second rotation shaft 44b, which are stirring rotation shafts, and is formed in a spiral shape at a constant pitch in the axial direction of the second rotation shaft 44b. And a spiral blade 44a. The second rotating shaft 44b extends to both end portions in the longitudinal direction of the developing container 22 (the axial direction of the second rotating shaft 44b), and one end of the second rotating shaft 44b is rotatable to the side wall 22e of the developing container 22. The other end side of the second rotation shaft 44b is rotatably supported by a second bearing portion 51d formed on the side wall 51h of the storage box 51. The other end side of the second rotation shaft 44b further extends into the accommodation box 51, and a second drive gear 56 made of a spur gear is fixed to the second rotation shaft 44b. Accordingly, when the second drive gear 56 rotates, the second spiral 44 rotates around the second rotation shaft 44b.

  The first spiral 43 (see FIG. 2) has a first rotation shaft 43b (see FIG. 2) that is a stirring rotation shaft. Although not shown, the first rotating shaft 43b has spiral blades that are provided integrally with the first rotating shaft 43b, as with the second spiral 44, and further includes a side wall 22e of the developing container 22 and a side wall 51h of the storage box 51. It is pivotally supported by the shaft. A first drive gear 55 (see FIG. 4) made of a spur gear is fixed on the extension of the first rotation shaft 43b, and when the first drive gear 55 rotates, the first spiral 43 rotates. The first drive gear 55 is accommodated in the accommodation box 51 (see FIG. 4).

  As described above, the fixed shaft 20d of the developing roller 20 is supported on the side wall 22e of the developing container 22 in a non-rotatable manner. On the other side of the developing roller 20, a third rotating shaft 20a that is a developing rotating shaft is disposed. The third rotating shaft 20a of the developing roller 20 is rotatably supported by a third bearing portion 51e formed on the side wall 51h of the storage box 51, and extends into the developing roller 20 so as to be concentric with the fixed shaft 20d. And is pivotally supported. Further, the third rotating shaft 20a extends into the accommodation box 51, and a third driving gear 57 made of a spur gear is fixed to the third rotating shaft 20a. Therefore, when the third drive gear 57 rotates, the developing roller 20 (developing sleeve 20c, see FIG. 2) rotates around the third rotating shaft 20a.

  Further, the fixed shaft 21 c of the magnetic roller 21 is supported by the side wall 22 e of the developing container 22 so as not to rotate. On the other side of the magnetic roller 21, a fourth rotating shaft 21 a that is a developing rotating shaft is disposed. The fourth rotating shaft 21a of the magnetic roller 21 is rotatably supported by a fourth bearing portion 51f formed on the side wall 51h of the storage box 51, and extends into the magnetic roller 21 so as to be concentric with the fixed shaft 21c. And is pivotally supported. Further, the fourth rotating shaft 21a extends into the accommodation box 51, and a fourth driving gear 58 made of a spur gear is fixed to the fourth rotating shaft 21a. Therefore, when the fourth drive gear 58 rotates, the magnetic roller 21 (magnetic sleeve 21b, see FIG. 2) rotates around the fourth rotation shaft 21a.

  As shown in FIG. 4, the first drive gear 55 and the second drive gear 56 are meshed to form a stirring gear, and the third drive gear 57 and the fourth drive gear 58 are meshed with an idle gear 59 interposed. And constitutes a developing gear. The idle gear 59 is rotatably supported in the storage box 51. The first drive gear 55 and the fourth drive gear 58 are meshed, and the fourth drive gear 58 is rotated by a drive source such as a motor (not shown). When the motor is driven, the third drive gear 57 is rotated from the fourth drive gear 58 via the idle gear 59, the first drive gear 55 is rotated by the fourth drive gear 58, and the second drive gear 56 is further rotated. Rotates. With these rotations, the first spiral 43 (see FIG. 2) rotates around the first rotation shaft 43b, the second spiral 44 (see FIG. 2) rotates around the second rotation shaft 44b, and further the developing roller. 20 (see FIG. 2) rotates around the third rotating shaft 20a, and the magnetic roller 21 (see FIG. 2) rotates around the fourth rotating shaft 21a. Instead of connecting the motor to the fourth drive gear 58, the motor may be connected to other drive gears 55 to 57.

  The drive gears 55 to 58 and the rotary shafts 20a, 21a, 43b, and 44b are each made of a material having high thermal conductivity such as aluminum, copper, iron, or an alloy containing these. The idle gear 59 is also preferably made of a material having high thermal conductivity.

  The sirocco fan 61 is fixed to the second rotating shaft 44b and is in contact with the flat surface of the second drive gear 56 (see FIG. 3). The sirocco fan 61 has a plurality of blades radially formed around the second rotation shaft 44b, and the plurality of blades are formed in a radial manner inclined with respect to the radial direction of the second rotation shaft 44b. . Therefore, when the second rotating shaft 44b rotates, the sirocco fan 61 takes in air from around the second rotating shaft 44b, and flows the taken air in the circumferential direction of the second rotating shaft 44b. It functions as a blowing member that flows to the outer edge side of the. Note that the plurality of blades of the sirocco fan 61 may be formed radially in the radial direction of the second rotating shaft 44b instead of being formed radially inclining with respect to the radial direction of the second rotating shaft 44b. Further, instead of the sirocco fan 61, the air blowing member may be constituted by a fan that causes air to flow in the circumferential direction of the second rotating shaft 44b, such as a turbo fan.

  The housing box 51 is formed of a resin in a substantially L-shaped box shape, and houses the drive gears 55 to 58, the idle gear 59, the rotary shafts 20a, 21a, 43b, and 44b and the sirocco fan 61 therein. Further, the storage box 51 is formed with an intake port 51a and an exhaust port 51b.

  The intake port 51 a is formed with a circular opening at the lower side of the storage box 51, while the exhaust port 51 b is formed with a rectangular opening at the upper side of the storage box 51.

  As shown in FIG. 3, a flange portion 51 g that protrudes in an annular shape toward the inside of the storage box 51 is formed at the opening edge of the intake port 51 a. The intake port 51 a faces the sirocco fan 61, and the flange portion 51 g of the intake port 51 a has a slight gap with the outer edge of the sirocco fan 61 and is disposed so as to overlap a part of the sirocco fan 61 in the axial direction. . On the other hand, the exhaust port 51 b is disposed at a position facing the flat surface of the third drive gear 57 in the accommodation box 51.

  Accordingly, when the sirocco fan 61 rotates, relatively cool air around the developing device 2 is taken into the storage box 51 from the intake port 51a. The air taken in from the intake port 51a flows from the periphery of the second drive gear 56 to the first drive gear 55 in the direction orthogonal to the first rotation shaft 43b, and further passes through the fourth drive gear 58 and the third drive gear 57. It will flow through the flow path (the direction of the broken arrow in FIGS. 3 and 4) reaching the exhaust port 51b.

  Here, the first and second spirals 43 and 44, the developing roller 20 and the magnetic roller 21 rotate in order to stir the developer and supply the stirred developer to the photoreceptor 11 (see FIG. 2). Heat generated by sliding friction between the rotary shafts 20a, 21a, 43b, 44b and the bearings of the rotary shafts of the storage box 51 is generated. The heat of the bearing portion diffuses to the rotating shafts 20a, 21a, 43b, 44b and the drive gears 55 to 58, which have a relatively large thermal conductivity, and further, the flow path (see FIG. 3 and the air flowing in the direction of the broken arrow in FIG. Further, as the drive gears 55 to 58 and the idle gear 59 rotate, the meshing portions of the gears also generate heat due to friction, but these heats are diffused throughout the drive gears 55 to 58 and the idle gear 59. Further, the air is discharged from the exhaust port 51 b together with the air flowing through the flow passage in the storage box 51.

  According to the embodiment, the developing device 2 includes the second spiral 44 that stirs the developer in the developer container 22, the second drive gear 56 that rotates the second spiral 44, the second spiral 44, and the second drive. A second rotating shaft 44b connected to the gear 56; Further, the developing device 2 includes a developing roller 20 that supplies a developer to the surface of the photoreceptor 11, a third driving gear 57 that forms a gear train with the second driving gear 56 and rotates the developing roller 20, and the developing roller 20. And a third rotating shaft 20 a that connects the third drive gear 57. Further, the developing device 2 accommodates the second and third drive gears 56 and 57 to rotatably support the second and third rotating shafts 44b and 20a, and discharges the air taken in and the intake port 51a that takes in air. A storage box 51 formed with an exhaust port 51b, and a second rotation shaft 44b provided in the storage box 51 to take air into the storage box 51 from the air intake port 51a and store the taken-in air in the storage box And a sirocco fan 61 that is passed through 51 and discharged from the exhaust port 51b.

  According to this configuration, when the first spiral 43 and the developing roller 20 rotate in order to stir the developer and supply the developer, the sliding friction occurs at the portion that rotatably supports the second and third rotating shafts 44b and 20a. In addition, the second and third drive gears 56 and 57 also generate heat due to friction. However, since the cold air outside the developing device 2 is circulated in the storage box 51 by the sirocco fan 61, these heats are exhausted from the exhaust port 51b of the storage box 51 together with the air flow, and the second and third. By cooling the rotating shafts 44b and 20a and the second and third drive gears 55 and 57, it is possible to suppress an increase in the temperature of the developer.

  Further, according to this configuration, since the air blowing member is constituted by the sirocco fan 61, even if the sirocco fan 61 is housed in the housing box 51 together with the second and third drive gears 56 and 57, the housing box 51 is large. There is no risk of conversion.

  Further, according to this configuration, the sirocco fan 61 is disposed in the vicinity of the intake port 51a of the storage box 51, whereby a large amount of air can be circulated in the storage box 51, and the second and third rotating shafts 44b. , 20a and the second and third drive gears 56, 57 can be efficiently cooled.

  As in the above embodiment, the sirocco fan 61 is provided on the second rotating shaft 44b, and an exhaust axial fan such as a propeller fan is provided on the second rotating shaft 44b so that the exhaust fan faces the exhaust port. As described above, an exhaust opening may be formed in the upper part of the side surface of the storage box 51. In this case, the plurality of rotating shafts and the drive gear are further cooled, and the temperature rise of the developer can be suppressed.

  Moreover, in the said embodiment, although the sirocco fan 61 was provided in the 2nd rotating shaft 44b arrange | positioned in the vicinity of the inlet 51a and the sirocco fan 61 was arrange | positioned facing the inlet 51a, this invention was shown. However, the present invention is not limited to this, and a plurality of rotating shafts and driving gears are cooled even if an axial fan for intake such as a propeller fan is provided on the second rotating shaft 44b and disposed opposite the intake port 51a. Thus, the temperature rise of the developer can be suppressed.

  Moreover, in the said embodiment, although the inlet port 51a was arrange | positioned in the lower part of the side surface of the storage box 51, and the exhaust port 51b was shown in the upper part of the side surface of the storage box 51, this invention is not limited to this, and an inlet port is shown. The configuration may be such that 51 a is arranged at the upper part of the side surface of the storage box 51 and the exhaust port 51 b is arranged at the lower part of the side surface of the storage box 51. In this case as well, the same effects as in the above embodiment can be obtained.

  Further, in the above embodiment, a part of the wall surface of the storage box 51 is configured by the side wall 51h. However, the present invention is not limited thereto, and a part of the wall surface of the storage box 51 is configured by the side wall of the developing container 22. You may make it the structure which provides the bearing which supports the drive gears 55-58 rotatably on the side wall.

  In the above embodiment, the present invention is applied to a configuration including the developing roller 20 and the magnetic roller 21. However, the present invention is not limited to this, and the developer is directly supplied from the stirring member to the developing roller without including the magnetic roller 21. You may apply to the structure which is made.

  INDUSTRIAL APPLICABILITY The present invention can be used for a developing device used in an image forming apparatus such as a copying machine, a printer, a facsimile, and a composite machine using the electrophotographic method, and an image forming apparatus including the developing device. The present invention can be used for a developing device that can be cooled and an image forming apparatus including the developing device.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2a-2d, 2 Developing apparatus 11a-11d, 11 Photoconductor 20 Developing roller (developing member)
20a Third rotation axis (development rotation axis)
20d Fixed shaft 21 Magnetic roller (developing member)
21a Fourth rotation axis (development rotation axis)
21c Fixed shaft 22 Developer container 42 Stirring member 43 First spiral 43b First rotating shaft (stirring rotating shaft)
44 2nd spiral 44b 2nd rotating shaft (stirring rotating shaft)
51 Accommodating box 51a Intake port 51b Exhaust port 51d Second bearing portion 51e Third bearing portion 51f Fourth bearing portion 51g Flange portion 55 First drive gear (stirring gear)
56 Second drive gear (stirring gear)
57 Third drive gear (development gear)
58 Fourth drive gear (development gear)
59 Idle Gear 61 Sirocco Fan (Blowing member)

Claims (4)

A stirring member for stirring the developer in the developing container;
A stirring gear for rotating the stirring member;
A stirring rotating shaft connecting the stirring member and the stirring gear;
A developing member for supplying a developer to the surface of the image carrier;
A developing gear that forms a gear train with the stirring gear and rotates the developing member;
A developing rotating shaft connecting the developing member and the developing gear;
A housing formed by housing the agitation gear and the developing gear to rotatably support the agitation rotating shaft and the developing rotation shaft, and forming an intake port for taking in air and an exhaust port for discharging the taken-in air. Box and
The storage box is provided on at least one rotation shaft of the stirring rotation shaft and the development rotation shaft, takes air into the storage box from the intake port, and allows the taken air to pass through the storage box. A developing device comprising: a blowing member that discharges from the exhaust port.   The developing device according to claim 1, wherein the air blowing member is provided on a rotating shaft disposed in the vicinity of the air inlet and is disposed to face the air inlet.   The developing device according to claim 2, wherein the air blowing member causes air to flow in a circumferential direction of the rotation shaft.   An image forming apparatus on which the developing device according to claim 1 is mounted.

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