JP5401410B2 - Developing device and image forming apparatus including the same - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention 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. The present invention relates to a developing device that replenishes developer and discharges excess developer, and an image forming apparatus including the developing device.

  In an image forming apparatus, a latent image formed on an image carrier made of a photoreceptor or the like is developed by a developing device and visualized as a toner image. As one of such developing devices, a two-component developing system using a two-component developer is employed. This type of developing device accommodates a developer composed of a carrier and toner in a developing container, and a developing roller for supplying the developer to the image carrier is disposed, and the developer in the developing container is conveyed and stirred. However, a stirring member that supplies the developing roller is disposed.

  In this developing device, the toner is consumed by the developing operation, while the carrier is not consumed and remains in the developing device. Accordingly, the carrier stirred together with the toner in the developing container deteriorates as the stirring frequency increases, and as a result, the charge imparting performance of the carrier to the toner gradually decreases.

  In view of this, there has been proposed a developing device in which a developer containing a carrier is replenished in a developing container and a surplus developer is discharged to suppress a decrease in charging performance.

  In the developing device that discharges excess developer as described above, when the image forming apparatus is installed and the apparatus main body is inclined, the height of the developer surface is biased in the developing container. If the developer discharge port is disposed at a position where the developer surface is highly biased, the developer is unnecessarily discharged, the amount of developer in the developer container is not stable, and the development performance of the developing device is adversely affected. There was a problem.

  Therefore, in Patent Document 1, a developer discharge port for discharging excess developer is formed in the developer container side wall on the downstream side in the developer conveyance direction in the developer container, and on the front side of the developer discharge port, A current plate is provided. The baffle plate is a vertical wall-like member extending vertically upward from the bottom surface of the developer container at a position facing the developer discharge port, and is configured to be higher than the upper end position of the developer discharge port. With this configuration, when the amount of developer in the developer container increases and the developer surface becomes higher, the flow of the developer near the developer discharge port is rectified by the rectifying plate, and the rectifying plate, the developer discharge port, Thus, fluctuations in the height of the developer surface due to the inclination of the developer container and the like are suppressed, and the amount of excess developer discharged is stabilized.

  In Patent Document 2, legs that support the four corners of the image forming apparatus are provided, and a developer discharge port is formed at a position in the longitudinal direction of the developer container corresponding to the center of the legs of the four corners. As a result, even when the developer container is inclined in the longitudinal direction, the developer surface in the developer container is less likely to be inclined at the developer discharge port, and the developer is discharged without being affected by the inclination of the developer container. A certain amount can be discharged from the outlet.

JP 2006-208577 A (paragraphs [0074] to [0076], FIG. 5) JP 7-1221021 A (paragraph [0036], FIG. 9)

  However, in Patent Document 1 described above, since the current plate is provided on the front side of the developer discharge port, the developer is transported to the developer discharge port side while avoiding the current plate, and the excess developer. Is not easily discharged to the developer discharge port, and it takes time for the amount of developer in the developer container to stabilize. Further, when the baffle plate is provided in the developing container, there is a problem that the configuration of the apparatus becomes complicated. Further, in Patent Document 2, the developer discharge port is provided in the developer container, but the developer discharge port is limited to a position corresponding to the substantially central portion of the apparatus, and a transport path for transporting the developer discharged from the developer container. An arrangement space such as the above is required, and the degree of freedom of the arrangement configuration for various members constituting the developing device is hindered.

  The present invention has been made to solve the above-described problems, and a developing device that stably discharges excess developer without restricting the arrangement of the developer discharge port even when the developer container is inclined. An object of the present invention is to provide an image forming apparatus including the same.

  In order to achieve the above object, a developing device according to a first aspect of the present invention includes a developing roller for supplying a developer to an image carrier, an agitating member for agitating and conveying the developer to be supplied to the developing roller, and the agitating member. A developer container for containing the developer stirred in this manner, a developer supply port through which the developer is supplied into the developer container, a developer discharge port through which excess developer in the developer container is discharged, A discharge adjusting member that is disposed opposite to the developer discharge port and adjusts the amount of developer discharged from the developer discharge port, and the discharge adjustment member faces the developer discharge port. A position having a restricting portion for restricting a lower edge of the outlet, and when the developing container is inclined so that the bulk of the developer at the developer discharge port is increased, the restricting portion is positioned higher than the developer discharge port. To the developer discharge port Of when the bulk tilts said developer container to be lower, the regulating unit is characterized in that to move to a position lower with respect to the developer discharge port.

  According to a second aspect of the present invention, in the above developing device, the restricting portion is formed in a step shape with respect to the bottom surface of the developing container.

  According to a third aspect of the present invention, in the above developing device, the restricting portion is formed to be continuously inclined with respect to the bottom surface of the developing container.

  According to a fourth aspect of the present invention, in the above developing device, the developer discharge port is formed on a side wall in the longitudinal direction of the developing container, and the discharge adjusting member is formed on an outer surface of the side wall of the developing container. It is characterized by being slidable along the part.

  According to a fifth aspect of the present invention, in the above developing device, the discharge adjusting member slides by its own weight according to the inclination of the developing container in the longitudinal direction.

  According to a sixth aspect of the present invention, in the above developing device, a pair of rotationally movable bodies that are capable of rolling along the guide portion are disposed on both sides in the sliding direction of the discharge adjustment member, and the discharge adjustment is performed. The member slides by the rolling movement of the rotary moving body.

  According to a seventh aspect of the present invention, in the above developing device, the guide portion is formed with a plurality of recesses for locking the rotary moving body to a predetermined inclination angle.

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

  According to the first invention, the developer is supplied into the developing container from the developer supply port, and the excess developer in the developing container is discharged from the developer discharge port. Here, if the developing device is installed at an inclination, the volume of the developer is biased up and down in the longitudinal direction with respect to the developer discharge port. The portion moves to a position that becomes higher than the developer discharge port, and the developer can be discharged from the developer discharge port by an appropriate amount. On the other hand, when the developer in the developer discharge port is inclined in a direction in which the volume of the developer is lowered, the regulating portion moves to a position lower than the developer discharge port, and discharges the developer from the developer discharge port by an appropriate amount. Can do. Therefore, even when the developer container is inclined, the excess developer can be stably discharged without restricting the arrangement of the developer discharge port in the developer container.

  In addition, according to the second aspect of the invention, since the restricting portion is formed in a step shape, the configuration for moving the discharge adjusting member can be simplified.

  According to the third aspect of the invention, since the restricting portion is continuously inclined, the developer can be accurately discharged from the developer discharge port according to the inclination of the developing container.

  According to the fourth aspect of the invention, since the discharge adjustment member is provided on the guide portion of the outer wall of the developing container, the discharge adjustment member can be reliably moved.

  According to the fifth aspect of the invention, since the discharge adjusting member moves by its own weight according to the inclination of the developing container in the longitudinal direction, it is not necessary to provide a special moving mechanism, and the structure becomes simple.

  According to the sixth aspect of the invention, the discharge adjustment member slides due to the rolling movement of the rotary moving body, so that the discharge adjustment member can be reliably moved.

  According to the seventh aspect of the invention, since the plurality of recesses for locking the rotary moving body to the predetermined inclination angle are formed, the lower end edge of the developer discharge port is formed according to the inclination of the developer container. The regulation position can be set accurately, and even when the developer container is inclined, the developer can be discharged from the developer discharge port by an appropriate amount.

  According to the eighth aspect of the present invention, there is provided an image forming apparatus including a developing device that stably discharges excess developer without restricting the arrangement of the developer discharge port even when the developer container is inclined. Can do.

1 is a diagram showing a schematic configuration of an image forming apparatus equipped with a developing device according to a first embodiment of the present invention. Side surface sectional drawing which shows schematic structure of the developing device which concerns on 1st Embodiment. Upper plan view showing a cross section of the agitator in the developing device according to the first embodiment. FIG. 2A is a plan view illustrating a discharge adjusting member in the developing device according to the first embodiment, and FIG. The figure which shows typically the state of the discharge adjustment member with respect to the inclination of the developing device which concerns on 1st Embodiment. The top view which shows typically the discharge adjustment member hold | maintained so that movement movement which concerns on 2nd Embodiment is possible. The top view which shows typically the discharge adjustment member hold | maintained so that movement movement which concerns on 3rd Embodiment is possible. The top view which shows typically the discharge adjustment member which concerns on 4th 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.

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus equipped with a developing device according to an embodiment of the present invention. The image forming apparatus 1 is provided with a sheet feeding unit 2 disposed in a lower portion thereof, a sheet conveying unit 3 disposed on a side of the sheet feeding unit 2, and an upper side of the sheet conveying unit 3. An image forming unit 4, a fixing unit 5 disposed on the discharge side of the image forming unit 4, an image reading unit 6 disposed above the image forming unit 4 and the fixing unit 5, and a hopper 110. I have.

  The paper feed unit 2 includes a plurality of paper feed cassettes 7 for containing paper 9, and the paper 9 from the paper feed cassette 7 selected from among the plurality of paper feed cassettes 7 by rotating the paper feed roller 8. Each sheet is sent out to the sheet transport unit 3.

  The paper 9 sent to the paper transport unit 3 is transported toward the image forming unit 4 via the paper transport path 10. The image forming unit 4 forms a toner image on a sheet 9 by an electrophotographic process. The image forming unit 4 is a photoconductor 11 supported so as to be rotatable in the direction of an arrow in FIG. A charging unit 12, an exposure unit 13, a developing device 14, a transfer unit 15, a cleaning unit 16, and a charge eliminating unit 17 are provided.

  The charging unit 12 includes a charging wire to which a high voltage is applied. When a predetermined potential is applied to the surface of the photoconductor 11 by corona discharge from the charging wire, the surface of the photoconductor 11 is uniformly charged. Then, when light based on the image data of the original read by the image reading unit 6 is irradiated to the photoconductor 11 by the exposure unit 13, the surface potential of the photoconductor 11 is selectively attenuated, and the surface of the photoconductor 11 is irradiated. An electrostatic latent image is formed.

  Next, the developing device 14 develops the electrostatic latent image on the surface of the photoconductor 11, and a toner image is formed on the surface of the photoconductor 11. This toner image is transferred by the transfer unit 15 to the paper 9 supplied between the photoconductor 11 and the transfer unit 15.

  The sheet 9 on which the toner image has been transferred is conveyed toward the fixing unit 5 disposed on the downstream side of the image forming unit 4 in the sheet conveying direction. In the fixing unit 5, the sheet 9 is heated and pressed by the heating member 18 and the pressure roller 19, and the toner image is melted and fixed on the sheet 9. Next, the sheet 9 on which the toner image is fixed is discharged onto the discharge tray 21 by the discharge roller pair 20.

  After the transfer by the transfer unit 15, the toner remaining on the surface of the photoconductor 11 is removed by the cleaning unit 16, and the residual charge on the surface of the photoconductor 11 is removed by the charge eliminating unit 17. Then, the photosensitive member 11 is charged again by the charging unit 12, and image formation is performed in the same manner.

  Next, the developing device will be described with reference to FIG. FIG. 2 is a side view showing a cross section of a schematic configuration of a developing device used in the image forming apparatus 1.

  The developing device 14 includes a developing container 22 that stores a two-component developer composed of toner and a carrier, first and second stirring members 23 and 24 that stir the developer, a developing roller 27, and a regulating member 28. I have.

  The developing container 22 constitutes an outline of the developing device 14, and is partitioned into a first transport path 22c and a second transport path 22d by a partitioning portion 22b at a lower portion thereof. The first transport path 22c and the second transport path 22d contain a developer composed of a carrier and toner. Further, the developing container 22 holds the first and second stirring members 23 and 24 and the developing roller 27 rotatably. Further, the developing container 22 has an opening that exposes the developing roller 27 toward the photoconductor 11. Further, a developer replenishing port 22g is provided in the upper part of the developing container 22, and when the developer in the developing container 22 falls below a predetermined amount, the developer is passed from the hopper 110 (see FIG. 1) via the developer replenishing port 22g. To be supplied into the developing container 22.

  The second agitating member 24 is provided in the second conveyance path 22d at the lower right side of the developing roller 27, and the first agitating member 23 is adjacent to the right side in the horizontal direction of the second agitating member 24, so that the first conveying path. 22c.

  The first and second stirring members 23 and 24 stir the developer 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 22c and the second transport path 22d. When the agitating member 23 rotates, the charged developer is transported from one communicating portion provided in the partition 22b to the second transport path 22d, and the developer passes through the first transport path 22c and the second transport path 22d. Circulate. Then, the developer is supplied from the second stirring member 24 to the developing roller 27.

  The developing roller 27 includes a fixed magnet body 25 and a developing sleeve 26. The developing sleeve 26 is made of a cylindrical nonmagnetic material and is rotatably supported by the developing container 22 at a position adjacent to the second stirring member 24. The fixed magnet body 25 is a permanent magnet fixed in the developing sleeve 26 and generates a magnetic field toward the developing sleeve 26. Further, the developing roller 27 is exposed from the opening of the developing container 22 and faces the photosensitive member 11 that is an image carrier at a predetermined interval. This facing area is a developing area D for supplying the developer carried on the developing sleeve 26 toward the photoreceptor 11. Further, a developing bias 29 in which alternating current is superimposed on direct current is applied to the developing sleeve 26 in order to supply toner to the photoreceptor 11.

  The regulating member 28 regulates the developer carried on the surface of the developing sleeve 26 to a predetermined layer thickness. The regulating member 28 has a blade shape and has a predetermined interval between the developing sleeve 26 and the surface of the developing sleeve 26. And attached to the developing container 22.

  The developer supplied from the second stirring member 24 is carried on the surface of the developing sleeve 26 by the magnetic force of the fixed magnet body 25 in the developing sleeve 26. The carried developer is regulated to a predetermined layer thickness by the regulating member 28, and is conveyed toward the developing flow area D by the rotation of the developing sleeve 26 in the arrow direction. When a developing bias 29 is applied to the developing sleeve 26, a potential difference is generated between the developing sleeve 26 and the photoconductor 11 in the developing region D, and the toner on the developing sleeve 26 is supplied to the photoconductor 11 and the photoconductor. The electrostatic latent image on 11 is developed into a toner image.

  Next, the stirring unit of the developing device will be described in detail with reference to FIG. FIG. 3 is an upper plan view showing a cross section of the stirring unit.

  As described above, the developer container 22 is formed with the first transport path 22c, the second transport path 22d, the partition 22b, and the communication sections 22e and 22f. In addition, the developer supply port 22g, the developer A discharge port 22h is formed. A discharge adjusting member 51 facing the developer discharge port 22h is provided on the outer wall of the developing container 22.

  The partition 22b of the developing container 22 extends in the longitudinal direction of the developing container 22 and partitions the first transport path 22c and the second transport path 22d in parallel. Communication portions 22e and 22f are provided at both end portions in the longitudinal direction of the partition portion 22b, and the developer is contained in the first conveyance path 22c, the communication section 22e, the second conveyance path 22d, and the communication section 22f. It is possible to circulate.

  A first stirring member 23 is disposed in the first transport path 22c, and a second stirring member 24 is disposed in the second transport path 22d.

  The 1st stirring member 23 has the rotating shaft 23b, the 1st spiral blade 23a, the stirring rib 23c, and the reverse spiral blade 23d.

  The rotation shaft 23 b is rotatably supported on the side wall of the developing container 22. The first spiral blades 23a are provided integrally with the rotation shaft 23b, and are formed in a spiral shape at a constant pitch in the axial direction of the rotation shaft 23b. The first spiral blade 23a extends in the longitudinal direction of the first transport path 22c and is provided to face the communication portion 22f. The stirring rib 23c is formed between the first spiral blades 23a in a flat plate shape, and is provided integrally with the rotating shaft 23b. By this stirring rib 23c, the developer is further stirred while being transported in the first transport path 22c. The reverse spiral blade 23d is a blade having a phase opposite to that of the first spiral blade 23a and is formed at least by one pitch, and is provided integrally with the rotation shaft 23b so as to face the communication portion 22e. When the reverse spiral blade 23d rotates, the developer conveyed to the downstream side (right side in FIG. 3) in the first conveyance path 22c is conveyed from the communication portion 22e to the second conveyance path 22d.

  The second stirring member 24 has a rotating shaft 24b, a second spiral blade 24a, and a reverse spiral blade 24d.

  The rotating shaft 24b is disposed in parallel with the rotating shaft 23b and is rotatably supported on the side wall of the developing container 22. The second spiral blades 24a are provided integrally with the rotary shaft 24b, and are formed in a spiral shape at a constant pitch in the axial direction of the rotary shaft 24b. The second spiral blade 24a is provided so as to extend beyond the axial length of the developing roller 27 in the second conveyance path 22d, and is provided to face the communication portion 22e. The reverse spiral blade 24d is a blade having a phase opposite to that of the second spiral blade 24a, and is formed for at least one pitch, and is provided integrally with the rotating shaft 24b so as to face the communication portion 22f. When the reverse spiral blade 24d rotates, the developer conveyed to the downstream side (left side in FIG. 3) in the second conveyance path 22d is conveyed from the communication portion 22f to the first conveyance path 22c.

  Accordingly, when the rotating shaft 23b is rotated by a driving source such as a motor or a gear train (not shown) during development, the first spiral blade 23a rotates together with the rotating shaft 23b, and the first spiral blade 23a is in the first transport path 22c. The developer is conveyed in the direction of arrow P. When the rotary shaft 24b is reversely rotated at the same rotational speed as the rotary shaft 23b in conjunction with the rotary shaft 23b, the second spiral blade 24a transports the developer in the second transport path 22d in the direction of the arrow Q. From the first transport path 22c, stirring is performed while circulating through the communication portion 22e, the second transport path 22d, and the communication portion 22f in order. Then, the developer is uniformly supplied from the second transport path 22d in the axial direction of the developing roller 27.

  Next, replenishment of new developer and discharge of excess developer will be described.

  The developer supply port 22g is disposed on the upstream side of the first conveyance path 22c (on the left side in FIG. 3) above the developer container 22. A new developer is supplied from the hopper 110 (see FIG. 1) provided at the top of the developer container 22 into the developer container 22 through the developer supply port 22g.

  The developer discharge port 22h is an opening for discharging the developer remaining in the developer container 22 by replenishment of the developer, and in the longitudinal direction on the downstream side (right side in FIG. 3) of the first transport path 22c. Is formed on the side wall 22p.

  When the toner is consumed by the development, the developer including the carrier is supplied from the developer supply port 22g into the first conveyance path 22c.

  The replenished developer is stirred while circulating from the first conveyance path 22c to the communication part 22e, the second conveyance path 22d, and the communication part 22f. The toner is discharged out of the developing container 22 through the discharge port 22h.

  Here, when the image forming apparatus 1 is installed, if the apparatus main body is tilted, the developing container 22 is also tilted. When the developer container 22 is inclined in the longitudinal direction, the developer amount in the developer container 22 is biased, and the developer volume is high on one side in the longitudinal direction and the developer volume is low on the other side. If the developer is discharged from the developer discharge port 22h in a tilted state, the developer in the developer container 22 is excessive or insufficient with respect to an appropriate amount of developer. If an excess or shortage of developer occurs in the developer container 22, the amount of developer supplied from the second transport path 22d to the developing roller 27 may not be constant, and the developing performance such as image density may be reduced.

  Therefore, in the present embodiment, the discharge adjustment member 51 is provided so as to face the developer discharge port 22h, and even when the developer container 22 is inclined, the discharge adjustment member 51 always discharges a predetermined amount of developer. I have to.

  The discharge adjustment member 51 will be described in detail with reference to FIG. 4A is a plan view showing the discharge adjusting member, and FIG. 4B is a cross-sectional view taken along the line AA of FIG. 4A showing the discharge adjusting member.

  The discharge adjusting member 51 is provided movably in the longitudinal direction at a position facing the developer discharge port 22h in a guide portion 22i formed integrally with the developer container 22. The guide portion 22i is formed in a groove shape that holds the discharge adjustment member 51 movably on the outer wall of the developer container 22 below the developer discharge port 22h.

  The discharge adjusting member 51 is formed of a resin or metal plate material having a stepped outline. A linear sliding portion 51e is formed on the lower side of the discharge adjusting member 51, and a restricting portion 51a, an upper restricting portion 51b, and a lower restricting portion 51c, which are three restricting portions, are formed in a step shape on the upper side. Further, contact portions 51f and 51g are formed on both sides thereof.

  Each regulation part 51a-51c regulates the lower end edge of the developer discharge port 22h, and is linearly formed with a length equal to or greater than the lateral width (length in the longitudinal direction) of the developer discharge port 22h. . The upper restricting portion 51b is formed at a position higher than the restricting portion 51a, and the lower restricting portion 51c is formed at a position lower than the restricting portion 51a. Therefore, when the discharge adjusting member 51 moves in the longitudinal direction, the height facing the opening of the developer discharge port 22h changes, the upper restricting portion 51b faces at the highest position, and the lower restricting portion 51c at the lowest position. The restricting portions 51a face each other at their intermediate positions.

  On the other hand, the guide portion 22i of the developing container 22 moves while the slide portion 22k that makes the sliding portion 51e of the discharge adjusting member 51 movably contact and the discharge adjusting member 51 always face the outer wall of the developing container 22. The holding portion 22j that holds the discharge adjusting member 51 and the contact portions 51f and 51g of the discharge adjusting member 51 can be in contact with each other, and the locking portions 22m and 22n that limit the range of movement of the discharge adjusting member 51 in the longitudinal direction. And have. The holding portion 22j and the slide portion 22k form a groove together with the outer wall of the developing container 22 (see FIG. 4B). When the developing container 22 is tilted, the discharge adjusting member 51 slides in its own groove due to its own weight. Will do.

  That is, when the developing container 22 is not inclined, the guide portion 22i is in a horizontal state, and the restricting portion 51a is at a position facing the developer discharge port 22h. When the developing container 22 is inclined with the right side in the longitudinal direction down, the guide portion 22i is inclined downward to the right, and the discharge adjustment member 51 moves to the right side by its own weight according to the inclination angle, and the discharge adjustment member 51 The abutting portion 51g abuts on the locking portion 22n. As a result, the discharge adjusting member 51 stops. At this time, the upper regulating portion 51b faces the developer discharge port 22h. On the other hand, when the developing container 22 is tilted with the left side in the longitudinal direction down, the guide portion 22i is tilted downward to the left, and the discharge adjusting member 51 moves to the left side by its own weight according to the tilt angle, and comes into contact with it. The part 51f contacts the locking part 22m. As a result, the discharge adjusting member 51 stops. At this time, the lower regulating portion 51c faces the developer discharge port 22h.

  The timing of movement of the discharge adjusting member 51 with respect to the inclination angle of the developing container 22 due to its own weight depends on the material and weight of the discharge adjusting member 51 and the contact surface between the sliding portion 51e of the discharge adjusting member 51 and the guide portion 22i. It is set based on the shape and roughness. For example, in order for the discharge adjusting member 51 to start moving at a relatively small inclination angle, the cross section (in FIG. 4B) of the sliding portion 51e of the discharge adjusting member 51 is formed in an arc shape, and the slide portion The contact surface with 22k is made smaller. Alternatively, a pair of rollers may be formed in a plate shape, and the rollers may be rotatably provided on the discharge adjusting member 51 so that the rollers roll on the slide portion 22k of the guide portion 22i.

  Therefore, when the image forming apparatus 1 is installed without tilting, the regulating portion 51a of the discharge adjusting member 51 faces the developer discharge port 22h, and the regulating portion 51a is the bottom surface 22q of the developing container 22 (see FIG. 4B). ) Is T. This height T corresponds to a predetermined developer surface in which an appropriate amount of developer is accommodated in the developing container 22, that is, always from the second stirring member 24 (see FIG. 3) to the developing roller 27 (see FIG. 3). An appropriate amount of developer is supplied and a good image is obtained.

  FIG. 5 is a diagram schematically showing the state of the discharge adjusting member with respect to the inclination of the developing container. FIG. 5A shows a case where the developing container is not inclined, and FIG. 5C shows a case where the developing container is inclined with the left side down. In the drawings, T indicates a predetermined developer surface, and Z indicates a developer amount corresponding to the predetermined developer surface T.

  As shown in FIG. 5A, when the developing container 22 is not inclined, the restricting portion 51a of the discharge adjusting member 51 faces the developer discharge port 22h. The developer is replenished from the developer replenishing port 22g (see FIG. 3), and the surplus developer accompanying the replenishment passes over the restricting portion 51a and is discharged to the outside of the developing container 22. The agent Z holds the predetermined developer surface T.

  As shown in FIG. 5B, when the developer container 22 is inclined with the right side in the longitudinal direction down, the developer bulk increases on the right side of the developer container 22, that is, on the developer discharge port 22h side. The developer is biased on the left side of the developing container 22 so as to reduce the bulk of the developer, and the discharge adjusting member 51 moves to the right by its own weight against friction with the guide portion 22i (see FIG. 4) of the developing container 22. It abuts on the locking portion 22n (see FIG. 4) of the guide portion 22i and stops. In this state, the upper restricting portion 51b faces the developer discharge port 22h, and the upper restricting portion 51b has a height corresponding to the bulkiness of the developer due to the inclination of the developer container 22, and the developer is discharged to the developer discharge port 22h. Will not be discharged from. Here, the developer is replenished from the developer replenishing port 22g (see FIG. 3), and surplus developer accompanying the replenishment passes over the upper regulating portion 51b and is discharged out of the developing container 22. The developer Z holds the predetermined developer surface T.

  Next, as shown in FIG. 5C, when the developing container 22 is inclined with the left side in the longitudinal direction down, the bulk of the developer increases on the left side of the developing container 22, and the right side of the developing container 22 That is, the developer discharge port 22h side is biased so that the bulk of the developer is lowered, and the discharge adjusting member 51 is on the left side by its own weight against the friction with the guide portion 22i (see FIG. 4) of the developer container 22. To contact the locking portion 22m (see FIG. 4) of the guide portion 22i and stop. In this state, the lower regulating portion 51c faces the developer discharge port 22h, and the lower regulating portion 51c has a height corresponding to the bulk of the developer due to the inclination of the developing container 22, so that the developer is discharged from the developer. There is no discharge from the outlet 22h. Here, the developer is replenished from the developer replenishing port 22g (see FIG. 3), and the excess developer accompanying the replenishment passes over the lower regulating portion 51c and is discharged out of the developing container 22, so that the inside of the developing container 22 This developer Z holds the predetermined developer surface T.

  In the first embodiment, the developer discharge port 22h is applied to the configuration in which the developer container 22 is disposed on the right side in the longitudinal direction of the developer container 22 (see FIG. 5). However, the present invention is not limited to this, and the developer discharge port 22h. May be applied to a configuration in which the developing container 22 is disposed on the left side in the longitudinal direction. In this case, when the upper regulating portion 51b is provided on the right side of the regulating portion 51a of the discharge adjusting member 51 and the lower regulating portion 51c is provided on the left side of the regulating portion 51a, the developing container 22 is similar to the first embodiment. The developer Z inside can hold a predetermined developer surface T.

  According to the first embodiment, the developing device 14 includes the developing roller 27 that supplies the developer to the photoreceptor 11, the stirring members 23 and 24 that stir and convey the developer supplied to the developing roller 27, and the stirring member. A developer container 22 that stores the developer agitated at 23, 24, a developer supply port 22 g through which the developer is supplied into the developer container 22, and a development in which excess developer in the developer container 22 is discharged. Agent discharge port 22h. Further, the developing device 14 includes a discharge adjusting member 51 that is disposed to face the developer discharge port 22h and adjusts the amount of developer discharged from the developer discharge port 22h. The discharge adjusting member 51 has restriction portions 51a to 51c that face the developer discharge port 22h and restrict the lower end edge of the developer discharge port 22h, and develop the developer so as to increase the bulk of the developer at the developer discharge port 22h. When the container 22 is tilted, the restricting portions 51a to 51c are moved to a position that is higher than the developer discharge port 22h. When the developer container 22 is tilted so that the volume of the developer at the developer discharge port 22h is tilted, The parts 51a to 51c move to positions that are lower than the developer discharge port 22h.

  According to this configuration, the developer is supplied into the developer container 22 from the developer supply port 22g, and the excess developer in the developer container 22 is discharged from the developer discharge port 22h. Here, when the developing device 14 is installed at an inclination, the volume of the developer is deviated vertically in the longitudinal direction with respect to the developer discharge port 22h, but is inclined in a direction in which the volume of the developer at the developer discharge port 22h increases. In some cases, the regulating portions 51a to 51c can move to a position that is higher than the developer discharge port 22h, and discharge the developer from the developer discharge port 22h by an appropriate amount. On the other hand, when the volume of the developer at the developer discharge port 22h is inclined in the direction of lowering, the restricting portions 51a to 51c move to a position lower than the developer discharge port 22h, and the developer is moved to the developer discharge port 22h. It is possible to discharge only an appropriate amount from. Therefore, even when the developer container 22 is inclined, the excess developer can be stably discharged without restricting the arrangement of the developer discharge port 22h in the developer container 22.

  Further, according to the first embodiment, the restricting portions 51 a to 51 c are formed in a step shape with respect to the bottom surface 22 q of the developing container 22, thereby simplifying the configuration for moving the discharge adjusting member 51. Can do.

  Further, according to the first embodiment, the developer discharge port 22h is formed in the longitudinal side wall 22p of the developing container 22, and the discharge adjusting member 51 moves by its own weight according to the inclination of the developing container 22 in the longitudinal direction. Therefore, it is not necessary to provide a special moving mechanism, and the configuration is simple.

(Second Embodiment)
FIG. 6 is a plan view schematically showing a discharge adjustment member that is movably held according to the second embodiment. In the second embodiment, the discharge adjusting member is moved by rolling the ball. The discharge adjustment member 51 and the ball 52 which are different from the first embodiment will be mainly described, and the description of the same parts as those of the first embodiment will be omitted hereinafter. In the second embodiment, the guide portion 22i has the holding portion 22j and the locking portions 22m and 22n as in the first embodiment, but the holding portion 22j and the locking portions 22m and 22n are omitted in FIG. It shows.

  The discharge adjusting member 51 has three step-like restricting portions 51a to 51c, a sliding portion 51e, and contact portions 51f and 51g, and is formed in a plate shape with a lightweight resin or the like. The pair of balls 52 that are rotationally movable bodies are formed of metal balls and can roll on the slide portion 22k of the guide portion 22i. Further, the pair of balls 52 are arranged to face the respective contact portions 51f and 51g of the discharge adjusting member 51. When the developing container 22 is tilted, the balls 52 roll and move on the slide portion 22k according to the tilt. . At this time, the ball 52 makes point contact with the slide portion 22k, and the ball 52 is easy to move with respect to the inclination of the developing container 22. In a state where the ball 52 is in contact with the contact portions 51f and 51g of the discharge adjustment member 51, when the developing container 22 is tilted, the discharge adjustment member 51 is pushed by the relatively heavy ball 52 and is driven. It should be noted that instead of the ball 52, a circular moving body may be formed by a cylindrical body, and the cylindrical body may be rolled.

  If the developer container 22 is not tilted, the regulating portion 51a of the discharge adjusting member 51 faces the developer discharge port 22h. When the developing container 22 is inclined with the right side down, the discharge adjusting member 51 is pushed by the ball 52 and moves to the right side and stops when it contacts the locking portion 22n (see FIG. 4). Accordingly, when the developer container 22 is inclined with the right side down and the developer volume increases at the developer discharge port 22h, the upper regulating portion 51b faces the developer discharge port 22h. On the other hand, when the developing container 22 is inclined with the left side down, the discharge adjusting member 51 is pushed by the ball 52 to move to the left side and stops when it contacts the locking portion 22m (see FIG. 4). Accordingly, when the developer container 22 is inclined with the left side down and the developer discharge port 22h has a low developer volume, the lower regulating portion 51c faces the developer discharge port 22h. Thus, an appropriate amount of developer can be discharged from the developer discharge port 22h regardless of which of the developer containers 22 is inclined.

(Third embodiment)
FIG. 7 is a plan view schematically showing a discharge adjustment member that is movably held according to the third embodiment. In the third embodiment, the discharge adjusting member is moved by rolling the ball, and further, there is a concave portion that holds the ball to a predetermined inclination angle. In the third embodiment, the guide portion 22i has the holding portion 22j and the locking portions 22m and 22n as in the first embodiment, but the holding portion 22j and the locking portions 22m and 22n are omitted in FIG. It shows.

  The discharge adjusting member 51 has four step-like restricting portions 51a to 51d, a sliding portion 51e, and contact portions 51f and 51g, and is formed in a plate shape with a lightweight resin or the like. Each of the restricting portions 51a to 51d includes an upper restricting portion 51b, a restricting portion 51a, a lower restricting portion 51c, and a lower restricting portion 51d in order from the highest, and the restricting portion 51a develops when the developing container 22 is not inclined. It faces the agent discharge port 22h.

  A pair of balls 52 that are rotationally movable bodies are formed of metal spheres and are disposed to face the contact portions 51f and 51g of the discharge adjustment member 51. Further, the pair of balls 52 make point contact with the slide portion 22k, and the balls 52 are easy to move with respect to the inclination of the developing container 22. In a state where the ball 52 is in contact with the discharge adjustment member 51, when the developing container 22 is tilted, the discharge adjustment member 51 is pushed by the relatively heavy ball 52 and is driven. It should be noted that instead of the ball 52, a circular moving body may be formed by a cylindrical body, and the cylindrical body may be rolled.

  A pair of concave portions 22ra and 22rc is formed on the slide portion 22k. The pair of recesses 22ra and 22rc are hemispherical recesses. When the ball 52 is fitted into the recesses 22ra and 22rc, the ball 52 remains in the recesses 22ra and 22rc until the developing container 22 is inclined at a predetermined angle. . The distance between the pair of recesses 22ra and 22rc in the longitudinal direction is set corresponding to the distance between the pair of balls 52 that are in contact with the contact portions 51f and 51g of the discharge adjustment member 51.

  The pair of concave portions 22ra has a predetermined depth from the slide portion 22k. When the pair of balls 52 are fitted into the pair of recesses 22ra, when the developing container 22 is tilted to the right or the left by exceeding a predetermined angle αa, the pair of balls 52 is released from the pair of recesses 22ra and the right side on the slide portion 22k. Or it can roll to the left. When the pair of balls 52 are fitted into the pair of recesses 22ra, the restricting portion 51a of the discharge adjusting member 51 corresponds to the developer discharge port 22h.

  The pair of recesses 22rc is formed deeper than the recess 22ra. When the pair of balls 52 are fitted in the pair of recesses 22rc, if the developing container 22 is tilted to the left by a predetermined angle αc, the pair of balls 52 is detached from the pair of recesses 22rc and rolls on the slide portion 22k to the left. It becomes possible. When the pair of balls 52 are fitted in the pair of recesses 22rc, the lower regulating portion 51c of the discharge adjusting member 51 corresponds to the developer discharge port 22h. The angle αc is larger than the angle αa.

  If the developer container 22 is not tilted, the pair of balls 52 are fitted and locked in the pair of recesses 22ra, and the restricting portion 51a of the discharge adjusting member 51 faces the developer discharge port 22h.

  When the developing container 22 is tilted beyond the predetermined angle αa with the right side down, the pair of balls 52 comes off from the pair of recesses 22ra, and the discharge adjustment member 51 is pushed by the balls 52 and moves to the right side. . When the discharge adjusting member 51 comes into contact with the locking portion 22n (see FIG. 4), the upper regulating portion 51b stops at a position facing the developer discharge port 22h. Accordingly, when the developer container 22 is inclined with the right side down and the developer volume increases at the developer discharge port 22h, the upper regulating portion 51b faces the developer discharge port 22h.

  On the other hand, when the developing container 22 is tilted with the left side down and exceeding a predetermined angle αa, the pair of balls 52 is disengaged from the pair of recesses 22ra, and the balls 52 move by pushing the discharge adjustment member 51 to the left side. Then, it fits into the recess 22rc and stops. As a result, the lower regulating portion 51c stops at a position facing the developer discharge port 22h. Accordingly, when the developer container 22 is inclined with the left side down and the developer volume is reduced at the developer discharge port 22h, the lower regulating portion 51c faces the developer discharge port 22h, and the developer container 22 is tilted in either direction. Also, an appropriate amount of developer can be discharged from the developer discharge port 22h.

  When the developing container 22 is further tilted with the left side down and exceeding a predetermined angle αb, the pair of balls 52 is disengaged from the pair of recesses 22rc, and the discharge adjustment member 51 is pushed by the balls 52 and further leftward. When moved and brought into contact with the locking portion 22m (see FIG. 4), the lower regulating portion 51d stops at a position facing the developer discharge port 22h. Accordingly, when the developer container 22 is inclined with the left side down and the developer volume is reduced at the developer discharge port 22h, the lower restriction portion 51c or the lower restriction portion 51d is moved to the developer discharge port 22h according to the inclination. The developer can be discharged more accurately from the developer discharge port 22h. In addition, you may make an upper side regulation part into two steps similarly to a lower side regulation part.

(Fourth embodiment)
FIG. 8 is a plan view schematically showing a discharge adjusting member according to the fourth embodiment. In the fourth embodiment, the regulating portion of the discharge adjustment member 51 is formed by continuously inclining. In the fourth embodiment, the guide portion 22i has the holding portion 22j and the locking portions 22m and 22n as in the first embodiment, but the holding portion 22j and the locking portions 22m and 22n are omitted in FIG. It shows.

  In the fourth embodiment, as in the first embodiment, the discharge adjustment member 51 may move by its own weight according to the inclination of the developing container 22 in the longitudinal direction, or as in the second embodiment. In addition, the ball 52 may roll on the slide portion 22k according to the inclination of the developing container 22 in the longitudinal direction, and the discharge adjustment member 51 may be pushed and moved by the ball 52.

  In either configuration, when the developer discharge port 22h is disposed on the right side in the longitudinal direction of the developer container 22, the restricting portion 51h is formed so as to be continuously inclined so that the right side is lowered. When the discharge port 22h is arranged on the left side in the longitudinal direction of the developing container 22, the restricting portion 51h is formed to be inclined so that the left side is continuously lowered. The inclination angle of the inclination restricting portion 51h is set based on an appropriate developer discharge amount with respect to the range of the inclination angle of the developer container 22 and the lateral width (length in the longitudinal direction) of the developer discharge port 22h.

  In the above embodiment, when the inclined developer container 22 changes to a horizontal state, the discharge adjustment member 51 moves in accordance with the change in the inclination of the developer container 22, and the regulating portion 51 a of the discharge adjustment member 51 moves the developer discharge. It will face the outlet 22h.

  When it is necessary to discharge the developer more accurately, the discharge adjustment member 51 is driven and controlled by a drive source such as a motor instead of the movement of the discharge adjustment member 51 due to its own weight or the movement of the ball 52. Good. In this case, the discharge adjusting member 51 having the inclination restricting portion 51h, a rack formed on the discharge adjusting member 51, a pinion that meshes with the rack, a motor that rotationally drives the pinion, and the vicinity of the developer discharge port 22h. It is good to make it the structure provided with the inclination-angle sensor provided in. When the inclination of the developing container 22 is detected by the inclination angle sensor and the rotational speed of the motor is controlled based on the detection result, the discharge adjustment member 51 is moved by a predetermined amount in the longitudinal direction by the rack and pinion mechanism, and the developing container An inclination regulating portion 51h corresponding to the inclination 22 is opposed to the developer discharge port 22h. The inclination restricting portion 51h continuously faces the developer discharge port 22h, so that a more accurate developer discharge amount can be obtained. In this configuration, the rack and pinion mechanism can be sealed in the developer and provided in the developing container 22, and the discharge adjusting member 51 can be provided to face the wall surface in the developing container 22. .

  Further, when the movement of the discharge adjusting member 51 is controlled according to the inclination of the developer container 22 using a motor, a rack and pinion mechanism, and an inclination angle sensor, the developer discharge port 22 h is orthogonal to the longitudinal direction of the developer container 22. The discharge adjusting member 51 may be formed on a wall surface (wall surface supporting the stirring members 23 and 24 in FIG. 3), and the developer discharge port 22h may be opposed to the developer discharge port 22h. In this configuration, when the developer container 22 is tilted so that the volume of the developer on the developer discharge port 22h side is increased, the discharge adjustment member 51 is controlled to move upward based on the detection result of the tilt angle sensor. When the developer container 22 is tilted so that the volume of the developer on the agent discharge port 22h side is lowered, the discharge adjusting member 51 is controlled to move downward based on the detection result of the tilt angle sensor. That is, the discharge adjusting member 51 moves in the vertical direction (height direction).

  In the above-described embodiment, an example is shown in which the present invention is applied to a monochrome copying machine. However, the present invention is not limited to this, and may be applied to a developing device for each color of a color copying machine or a color printer.

  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. Can be used for a developing device that replenishes the two-component developer and discharges excess developer and an image forming apparatus equipped with the developing device.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 11 Photosensitive body (image carrier)
14 Developing Device 22 Developing Container 22g Developer Supply Port 22h Developer Discharge Port 22i Guide Portion 22j Holding Portion 22k Slide Portion 22m, 22n Locking Portion 22p Side Wall 22q Bottom Surface 22ra, 22rc Recess 23 First Stirring Member 24 Second Stirring Member 27 Developing roller 51 Discharge adjusting member 51a Restricting portion 51b Upper restricting portion (regulating portion)
51c, 51d Lower side regulation part (regulation part)
51e Sliding part 51f, 51g Contact part 51h Inclination restricting part (regulating part)
52 balls (rotary moving body)
T Predetermined developer surface Z Developer

Claims (6)

A developing roller for supplying a developer to the image carrier;
A stirring member that stirs and conveys the developer supplied to the developing roller;
A developer container containing the developer stirred by the stirring member;
A developer supply port through which developer is supplied into the developer container;
A developer outlet for discharging excess developer in the developer container;
A discharge adjusting member that is disposed opposite to the developer discharge port and adjusts the amount of developer discharged from the developer discharge port;
The developer discharge port is formed on a longitudinal side wall of the developer container,
Wherein with exhaust adjusting member is closed the regulating portion for regulating a lower edge of the developer discharge port so as to face the developer discharge opening, slides along a guide portion formed on an outer surface of the side wall of said developer container Is provided, and slides by its own weight according to the inclination in the longitudinal direction of the developing container,
When the developer container is tilted so that the volume of the developer at the developer discharge port is increased, the restricting portion moves to a position that is higher than the developer discharge port, and the developer at the developer discharge port The developing device according to claim 1, wherein when the developing container is inclined so as to be low in volume, the restricting portion moves to a position where the regulating portion is lowered with respect to the developer discharge port. A developing roller for supplying a developer to the image carrier;
A stirring member that stirs and conveys the developer supplied to the developing roller;
A developer container containing the developer stirred by the stirring member;
A developer supply port through which developer is supplied into the developer container;
A developer outlet for discharging excess developer in the developer container;
A discharge adjusting member that is disposed opposite to the developer discharge port and adjusts the amount of developer discharged from the developer discharge port;
The developer discharge port is formed on a longitudinal side wall of the developer container,
Wherein with exhaust adjusting member is closed the regulating portion for regulating a lower edge of the developer discharge port so as to face the developer discharge opening, slides along a guide portion formed on an outer surface of the side wall of said developer container Is possible,
A pair of rotationally movable bodies that can move and roll along the guide portions are disposed on both sides of the sliding direction of the discharge adjusting member, and the discharge adjusting member slides by the rolling movement of the rotationally movable body,
When the developer container is tilted so that the volume of the developer at the developer discharge port is increased, the restricting portion moves to a position that is higher than the developer discharge port, and the developer at the developer discharge port The developing device according to claim 1, wherein when the developing container is inclined so as to be low in volume, the restricting portion moves to a position where the regulating portion is lowered with respect to the developer discharge port. The developing device according to claim 2 , wherein the guide portion is formed with a plurality of recesses for locking the rotary moving body to a predetermined inclination angle. The developing device according to claim 1, wherein the restricting portion is formed in a step shape with respect to a bottom surface of the developing container. The developing device according to claim 1, wherein the restricting portion is formed to be continuously inclined with respect to a bottom surface of the developing container. The image forming apparatus in which the developing device is mounted according to any one of claims 1 to 5.

Images