JP2013029625A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of reducing the occurrence frequency of downtime during which printing is interrupted.SOLUTION: A photoreceptor unit U1 includes a photoreceptor drum 7 which carries an electrostatic latent image thereon and a cleaner 15 which recovers a toner remained on the photoreceptor drum 7 after transfer of a toner image. A toner storage container B1 is constituted integrally with the photoreceptor unit U1, and stores the toner recovered by the cleaner 15. A developing unit U2 discharges a part of a stored developer and forms a toner image by applying the toner to the photoreceptor drum 7 to develop the electrostatic latent image. A developer storage container B2 is constituted integrally with the developing unit U2, and stores the developer discharged by the developing unit U2. The photoreceptor unit U1 and the toner storage container B1, and the developing unit U2 and the developer storage container B2 are attachable to/detachable from a body 10.

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus that develops an electrostatic latent image with toner.

  In an image forming apparatus using a two-component developer, a development method called a trickle development method has begun to be adopted. In the conventional developing method, only toner is supplied to the developing device, whereas in the trickle developing method, a developer composed of toner and a carrier is supplied to the developing device. Thereby, deterioration of a carrier is suppressed. As an image forming apparatus to which such a trickle developing method is applied, for example, an image forming apparatus described in Patent Document 1 is known.

  The image forming apparatus described in Patent Document 1 discharges the developer from the developing device when the developer composed of toner and carrier is supplied to the developing device. Further, in the image forming apparatus, the toner remaining on the photosensitive drum after development is collected by a cleaning device. In view of this, the image forming apparatus includes a waste powder recovery container for storing the developer discharged from the developing device and the toner recovered by the cleaning device. Such a waste powder collection container is provided with a sensor, and when the user detects that the sensor is full, the user replaces the waste powder collection container.

  Incidentally, the image forming apparatus described in Patent Document 1 has a problem that frequent downtime occurs when printing is interrupted. More specifically, when the waste powder collection container is replaced, printing is interrupted, and downtime occurs. In the image forming apparatus, when the developing device deteriorates, the developing device is replaced. For this reason, since the printing is interrupted when the developing device is replaced, downtime occurs. Further, in the image forming apparatus, when the photosensitive drum is deteriorated, the photosensitive unit is replaced. As a result, printing is interrupted when the photosensitive unit is replaced, resulting in downtime. As described above, in the image forming apparatus described in Patent Document 1, downtime occurs at three types of timing.

JP 2010-122368 A

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus that can reduce the frequency of downtime during which printing is interrupted.

  An image forming apparatus according to an aspect of the present invention includes a first unit including a latent image carrier that carries an electrostatic latent image, a toner container that is configured integrally with the first unit, and a toner. And a second unit for containing a developer composed of a carrier and discharging a part of the contained developer, by applying toner to the latent image carrier, and by a trickle development system. A second unit that develops the electrostatic latent image to form a toner image, and a developer container that is configured integrally with the second unit and that stores the developer discharged by the second unit. A container; a transfer unit that transfers the toner image from the latent image carrier to a transfer target; and the first unit, the toner storage container, the second unit, the developer storage container, and a transfer unit. With the main body The first unit further includes a recovery unit that recovers toner remaining on the latent image carrier after the transfer of the toner image, and the toner storage container includes the recovery unit. The collected toner is accommodated, and the first unit and the toner container, and the second unit and the developer container are detachable from the main body.

  According to the present invention, it is possible to reduce the frequency of downtime during which printing is interrupted.

1 is a diagram illustrating an overall configuration of an image forming apparatus. FIG. 3 is a perspective view of the developing unit from the positive side in the z-axis direction. It is the figure which saw through the exchange unit from the negative direction side of the x-axis direction. It is the figure which saw through the exchange unit from the positive direction side of the z-axis direction. It is the figure which showed the mode at the time of removing an exchange unit from a main body. It is the figure which planarly viewed the exchange unit from the negative direction side of the x-axis direction.

  Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described.

(Configuration of image forming apparatus)
Hereinafter, a configuration of an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of the image forming apparatus 1. In the following, the vertical direction in FIG. 1 is defined as the z-axis direction, the horizontal direction in FIG. 1 is defined as the x-axis direction, and the vertical direction in FIG. 1 is defined as the y-axis direction.

  The image forming apparatus 1 is an electrophotographic monochrome printer and forms a black image. The image forming apparatus 1 has a function of forming a toner image on a sheet (transfer object) based on image data read by a scanner. As shown in FIG. Roller pair 6, optical scanning device 9, transfer roller 14, eraser 19, fixing device 20, paper discharge roller pair 21, paper discharge tray 22, photosensitive unit (first unit) U1, developer unit (second unit) ) U2, a toner storage container B1, and a developer storage container B2.

  The main body 2 includes a paper feeding unit 3, a timing roller pair 6, an optical scanning device 9, a transfer roller 14, an eraser 19, a fixing device 20, a paper discharge roller pair 21, a photosensitive unit U1, a developing unit U2, and a toner container B1. And a developer storage container B2.

  The paper feed unit 3 serves to supply paper one by one and includes a paper tray 4 and a paper feed roller 5. On the paper tray 4, a plurality of sheets in a state before printing are stacked and placed. The paper feed roller 5 takes out the paper placed on the paper tray 4 one by one. The timing roller pair 6 conveys the paper while adjusting the timing so that the toner image is secondarily transferred onto the paper by the transfer roller 14.

  The photoreceptor unit U1 includes a photoreceptor drum 7, a charger 8, and a cleaner 15. The photosensitive drum 7 has a cylindrical shape, and rotates counterclockwise as shown in FIG. The photosensitive drum 7 functions as an electrostatic latent image carrier that carries an electrostatic latent image on its peripheral surface. The charger 8 negatively charges the peripheral surface of the photosensitive drum 7. As a result, the potential on the peripheral surface of the photosensitive drum 7 is maintained at −500V to −400V.

  The optical scanning device 9 scans the beam on the peripheral surface of the photosensitive drum 7 under the control of a control unit (not shown). The potential of the portion irradiated with the beam approaches 0V. As a result, an electrostatic latent image is formed on the peripheral surface of the photosensitive drum 7.

  The developing unit U2 forms a toner image on the photosensitive drum 7 by trickle development. Specifically, the developing unit U2 applies toner to the photosensitive drum 7 to develop the electrostatic latent image to form a toner image. The developing unit U2 accommodates a two-component developer composed of a nonmagnetic toner and a magnetic carrier, and discharges a part of the accommodated developer upon supply of the developer. Hereinafter, the developing unit U2 will be described with reference to the drawings. FIG. 2 is a perspective view of the developing unit U2 seen from the positive side in the z-axis direction.

  As shown in FIG. 2, the developing unit U <b> 2 includes a developing roller 10 (not shown in FIG. 2), a supply screw 11, a stirring screw 12, and a main body 13. The developing unit U2 includes other configurations such as a motor and a gear, but these configurations are omitted in FIG.

  The main body 13 is a housing that houses the developer, the developing roller 10, the supply screw 11, and the stirring screw 12. The main body 13 extends in the y-axis direction, and forms a supply space Sp1, a stirring space Sp2, discharge spaces Sp3 and Sp4, and a replenishment space Sp5 that are adjacent to each other in the x-axis direction. The stirring space Sp2 is provided on the negative side in the x-axis direction with respect to the supply space Sp1 in the main body 13. The stirring space Sp2 and the supply space Sp1 are connected at both ends in the y-axis direction.

  The discharge space Sp3 is provided on the positive side of the supply space Sp1 in the y-axis direction. The discharge space Sp3 has a smaller cross-sectional area than the supply space Sp1. The discharge space Sp4 is provided on the positive direction side in the y-axis direction of the discharge space Sp3. The discharge space Sp4 has a smaller cross-sectional area than the discharge space Sp3. In addition, an opening H2 is provided on the surface of the discharge space Sp4 on the negative direction side in the z-axis direction.

  The replenishment space Sp5 is provided on the positive direction side in the y-axis direction of the stirring space Sp2. An opening H1 is provided in the surface on the positive direction side in the z-axis direction of the supply space Sp5.

  The stirring screw 12 is provided in the stirring space Sp2 and the replenishing space Sp5, and extends in the y-axis direction. The stirring screw 12 is rotated to convey the developer toward the negative side in the y-axis direction while stirring the developer. As a result, the toner is negatively charged and the carrier is positively charged. The developer conveyed by the stirring screw 12 flows into the supply space Sp1 from the negative end of the stirring space Sp2 in the y-axis direction.

  The supply screw 11 is provided in the supply space Sp1 and the discharge spaces Sp3 and Sp4, and extends in the y-axis direction. The supply screw 11 is rotated to convey the developer toward the positive direction side in the y-axis direction. Then, the developer conveyed by the supply screw 11 flows into the stirring space Sp2 from the end portion on the positive direction side in the y-axis direction of the supply space Sp1. Therefore, the developer circulates between the stirring space Sp2 and the supply space Sp1.

  The developing roller 10 is provided in the supply space Sp1 and extends in the y-axis direction. As a result, the developing roller 10 faces the supply screw 11. Further, the developing roller 10 is exposed from the main body 13 and faces the photosensitive drum 7. The developing roller 10 incorporates a magnet, and adsorbs a magnetic carrier together with non-magnetic toner by a magnetic force to carry the developer conveyed by the supply screw 11.

  The developing roller 10 is in pressure contact with the photosensitive drum 7 and applies toner to the photosensitive drum 7 to develop the electrostatic latent image. Specifically, the developing bias is applied to the developing roller 10 so that the potential on the peripheral surface of the developing roller 10 is negative. The potential of the peripheral surface of the developing roller 10 is −400V to −350V. As a result, the potential on the peripheral surface of the developing roller 10 is lower than the potential (approximately 0 V) of the portion irradiated with the beam on the peripheral surface of the photosensitive drum 7 and the beam on the peripheral surface of the photosensitive drum 7 is irradiated. It becomes higher than the potential (−500 V to −400 V) of the portion that is not. The non-magnetic toner in the developer carried by the developing roller 10 is negatively charged, and therefore adheres to the portion irradiated with the beam on the peripheral surface of the photosensitive drum 7. As a result, a negatively charged toner image is formed on the peripheral surface of the photosensitive drum 7.

  The opening H1 is connected to a toner bottle (not shown). The developer is supplied from the toner bottle to the supply space Sp5 through the opening H1. The developer supplied to the replenishment space Sp5 is conveyed to the stirring space Sp2 by the stirring screw 12.

  The opening H2 is connected to the developer storage container B2. Since the supply screw 11 conveys the developer toward the positive direction side in the y-axis direction, the developer that could not flow into the stirring space Sp2 at the end portion on the positive direction side in the y-axis direction of the supply space Sp1 It is conveyed to the discharge spaces Sp3, Sp4. Then, the developer is discharged out of the main body 13 through the opening H2. However, in order to prevent the developer from being discharged too much, the winding direction in the portion of the supply screw 11 positioned in the discharge space Sp3 is the portion of the supply screw 11 positioned in the supply space Sp1 and the discharge space Sp4. Is the reverse direction of the winding direction. Accordingly, the supply screw 11 conveys the developer toward the negative side in the y-axis direction in the discharge space Sp3. As a result, the developer is prevented from excessively flowing into the discharge spaces Sp3 and Sp4. However, the conveyance capability of the part located in supply space Sp1 of supply screw 11 is higher than the conveyance capability of the part located in discharge space Sp3 of supply screw 11. Therefore, the developer advances in the discharge space Sp3 toward the positive direction side in the y-axis direction.

  The developer storage container B2 is configured integrally with the developing unit U2, and stores the developer discharged by the developing unit U2. Hereinafter, the developer unit U2 and the developer container B2 are collectively referred to as an exchange unit A2. Hereinafter, the developer container B2 will be described with reference to the drawings. FIG. 3 is a perspective view of the replacement unit A2 from the negative side in the x-axis direction.

  As shown in FIGS. 1 and 3, the developer container B <b> 2 is provided on the negative side of the developing unit U <b> 2 in the z-axis direction, and includes a main body 30 and a conveying screw 31. The developer container B2 includes other components such as a motor and a gear, but these components are omitted in FIG.

  The main body 30 forms an accommodation space Sp9. The accommodation space Sp9 is a space extending in the y-axis direction, as shown in FIG. An opening H3 is provided in the surface on the positive direction side in the z-axis direction of the accommodation space Sp9. The opening H3 and the opening H2 are connected. As a result, the developer discharged from the developing unit U2 through the opening H2 flows into the accommodation space Sp9 through the opening H3.

  The conveying screw 31 is provided in the accommodation space Sp9 and extends in the y-axis direction. The conveying screw 31 conveys the developer flowing in from the developing unit U2 toward the negative side in the y-axis direction by being rotated. As a result, the collected developer toner is evenly dispersed in the accommodation space Sp9. This is the end of the description of the configuration of the developer container B2.

  The transfer roller 14 functions as a transfer unit that transfers the toner image from the photosensitive drum 7 to a sheet. Specifically, the transfer roller 14 is in contact with the photosensitive drum 7 and has a drum shape. A positive bias voltage is applied to the transfer roller 14. As a result, the transfer roller 14 transfers the toner image carried by the photosensitive drum 7 onto the sheet passing between the photosensitive drum 7 and the transfer roller 14. More specifically, the photosensitive drum 7 is maintained at a negative potential (−500 V to −400 V). A positive bias voltage is applied to the transfer roller 14 so that the potential of the transfer roller 14 is higher than the potential of the photosensitive drum 7. Since the toner image is negatively charged, the toner image is transferred from the photosensitive drum 7 to the sheet by an electric field generated between the photosensitive drum 7 and the transfer roller 14.

  The cleaner 15 is a collecting unit that collects the toner remaining on the photosensitive drum 7 after the transfer of the toner image. The toner storage container B1 is configured integrally with the photosensitive unit U1, and stores the toner collected by the cleaner 15. Hereinafter, the photosensitive unit U1 and the toner container B1 are collectively referred to as an exchange unit A1. As shown in FIG. 1, the exchange unit A1 is provided closer to the positive direction side in the z-axis direction than the exchange unit A2. Hereinafter, the cleaner 15 and the toner container B1 will be described with reference to the drawings. FIG. 4 is a perspective view of the replacement unit A1 from the positive side in the z-axis direction.

  As shown in FIGS. 1 and 4, the cleaner 15 includes a blade 16, a cleaning member 17, conveying screws 18 and 42, and a main body 40. The replacement unit A1 includes other configurations such as a motor and gears, but these configurations are omitted in FIG.

  The main body 40 is a housing that houses the blade 16, the cleaning member 17, and the transport screw 18, and forms a recovery space Sp6 and a transport space Sp7. The collection space Sp6 is a space extending in the y-axis direction, as shown in FIG. The conveyance space Sp7 is a space extending in the x-axis direction as shown in FIG. The end portion on the negative direction side in the y-axis direction of the collection space Sp6 is connected to the end portion on the positive direction side in the x-axis direction of the transport space Sp7.

  The blade 16 is in contact with the peripheral surface of the photosensitive drum 7 and scrapes off the toner remaining after the transfer of the toner image from the peripheral surface of the photosensitive drum 7. The toner thus scraped off adheres onto the blade 16. The cleaning member 17 wipes off the toner adhering to the blade 16 and conveys it to the conveying screw 18. The cleaning member 17 is configured by attaching a film to a shaft extending in the y-axis direction. Then, the shaft is rotated clockwise, and the film is brought into sliding contact with the blade 16, whereby the toner attached to the blade 16 is wiped off and sent to the conveying screw 18.

  The conveying screw 18 is provided in the recovery space Sp6 and extends in the y-axis direction. The transport screw 18 is rotated to transport the toner toward the negative side in the y-axis direction. The toner transported by the transport screw 18 flows into the transport space Sp7 from the negative end of the recovery space Sp6 in the y-axis direction.

  The transport screw 42 is provided in the transport space Sp7 and extends in the x-axis direction. The conveying screw 42 is rotated to convey the toner toward the negative direction side in the x-axis direction. The toner transported by the transport screw 42 flows into the toner storage container B1 from the negative end of the transport space Sp7 in the x-axis direction.

  The toner storage container B1 stores the toner collected by the cleaner 15, and includes a main body 32, a conveying screw 33, and a stirring screw 34 as shown in FIGS. The main body 32 forms an accommodation space Sp8. As shown in FIG. 4, the accommodation space Sp8 is a space extending in the y-axis direction, and is connected to an end portion on the negative direction side in the x-axis direction of the transport space Sp7.

  The conveying screw 33 is provided in the accommodation space Sp8 and extends in the y-axis direction. Further, the negative end of the transport screw 33 in the y-axis direction is located at the negative end of the transport space Sp7 in the x-axis direction. The conveyance screw 33 is rotated to convey the toner flowing in from the conveyance space Sp7 toward the positive side in the y-axis direction. Thereby, the conveyance screw 33 disperses the collected toner evenly in the accommodation space Sp8.

  The agitating screw 34 is provided in the accommodation space Sp8 and extends in the y-axis direction. The stirring screw 34 is provided on the negative side of the conveying screw 33 in the x-axis direction. The conveying screw 33 agitates the toner in the accommodation space Sp8 by being rotated. As a result, the toner is prevented from solidifying in the accommodation space Sp8. This is the end of the description of the configurations of the cleaner 15 and the toner container B1.

  The eraser 19 neutralizes the photosensitive drum 7 after the toner image is transferred. More specifically, the eraser 19 is provided on the positive side of the toner storage container B1 in the z-axis direction, and irradiates the circumferential surface of the photosensitive drum 7 with light. As a result, the potential on the peripheral surface of the photosensitive drum 7 becomes approximately 0V. The eraser 19 can swing around the end on the negative direction side in the x-axis direction. More specifically, as shown by the dotted line in FIG. 1, the eraser 19 can be retracted to a position that does not overlap with the toner container B1 when viewed in plan from the x-axis direction by rotating counterclockwise. .

  The sheet on which the toner image is transferred is conveyed to the fixing device 20. The fixing device 20 fixes the toner image on the paper by performing heat treatment and pressure treatment on the paper. As shown in FIG. 1, the fixing device 20 is provided on the positive side in the z-axis direction with respect to the replacement unit A1. The paper discharge roller pair 21 outputs the paper to the paper discharge tray 22. Printed paper is placed on the paper discharge tray 22.

  In the image forming apparatus 1 configured as described above, the replacement units A1 and A2 can be attached to and detached from the main body 2. Specifically, the replacement unit A1 is attached to and detached from the main body 2 by being moved in the horizontal direction (that is, the x-axis direction) perpendicular to the rotation axis of the photosensitive drum 7. Further, the replacement unit A2 is attached to and detached from the main body 2 by being moved in a direction (y-axis direction) in which the rotation shaft of the photosensitive drum 7 extends. Hereinafter, the attachment / detachment of the replacement units A1 and A2 will be described with reference to the drawings. FIG. 5 is a diagram showing a state when the replacement unit A1 is removed from the main body. FIG. 6 is a plan view of the replacement units A1 and A2 from the negative direction side in the x-axis direction.

  First, attachment / detachment of the replacement unit A1 will be described. First, the user opens the door constituting the side surface of the main body 2 on the positive direction side in the x-axis direction. In conjunction with the opening of the door, as shown in FIG. 5A, the eraser 19 retracts to a position that does not hinder the removal of the replacement unit A1 from the main body 2. Specifically, the eraser 19 rotates counterclockwise and retracts to a position that does not overlap with the toner storage container B1 when viewed in plan from the x-axis direction. Further, since the transfer roller 14 is attached to the door, it retracts from the front of the photosensitive drum 7 together with the door.

  Next, the user moves the replacement unit A1 in the direction in which the developing roller 10 is in pressure contact with the photosensitive drum 7, as shown in FIG. The pressure contact between the developing roller 10 and the photosensitive drum 7 is regulated so that it cannot move beyond a predetermined stroke, so that the developing roller 10 and the photosensitive drum 7 are separated from each other. The direction in which the developing roller 10 is in pressure contact with the photosensitive drum 7 is a direction from the center of the developing roller 10 toward the center of the photosensitive drum 7 when viewed in plan from the y-axis direction.

  After the developing roller 10 and the photosensitive drum 7 are separated from each other, the user moves the replacement unit A1 to the positive side in the x-axis direction and removes it from the main body 2 as shown in FIG. This completes the removal of the replacement unit A1 from the main body 2. Note that the attachment of the replacement unit A1 to the main body 2 is the reverse of the procedure for removing the replacement unit A1 from the main body 2, and thus the description thereof is omitted.

  As described above, in the image forming apparatus 1, the photoreceptor unit U1 and the toner container B1 are simultaneously replaced. Therefore, it is preferable that the time required for the toner storage container B1 to be filled with toner is longer than the lifetime of the photoreceptor unit U1. As a result, the photoconductor unit U1 and the toner container B1 can be replaced after the photoconductor unit U1 has been used up to the end of its life.

  The toner container B1 has a configuration described below in order to allow the replacement unit A1 to be attached to and detached from the main body 2. More specifically, the toner container B1 is provided on the negative side in the x-axis direction (that is, on the upstream side in the removal direction of the replacement unit A1) from the photosensitive drum 7. Further, the length z1 (see FIG. 1) in the z-axis direction on the negative side in the x-axis direction from the photosensitive drum 7 of the photosensitive unit U1 and the length z2 in the z-axis direction of the toner container B1 (see FIG. 1). 1) is shorter than the opening width z3 (see FIG. 1) between the fixing device 20 and the developing unit U2 in the z-axis direction. Further, in FIG. 5B, if the z-axis component of the amount of movement of the developing roller 10 in the direction opposite to the direction in which the developing roller 10 is pressed against the photosensitive drum 7 is z4, z1 to z4 are the following. It is preferable that the relationship is established. z3> (z1 + z4), z3> (z2 + z4)

  This prevents the toner container B1 from coming into contact with the fixing device 20 or the developer unit U2 when the replacement unit A1 is removed.

  Next, attachment / detachment of the replacement unit A2 will be described. The replacement unit A2 cannot be removed from the main body 2 when the replacement unit A1 is attached to the main body 2. Specifically, as shown in FIG. 6D, a part of the toner container B1 of the replacement unit A1 is located on the positive side in the y-axis direction with respect to the developing unit U2 of the replacement unit A2. Thereby, in the state where exchange unit A2 was attached to main part 2, exchange unit A1 cannot be pulled out to the positive direction side of the y-axis direction. Therefore, when removing the replacement unit A2, the replacement unit A1 is removed before the replacement unit A2.

  Next, the user opens the door on the positive side of the main body 2 in the y-axis direction. Then, the user moves the replacement unit A2 to the positive side in the y-axis direction and removes it from the main body 2. Thereby, the removal of the replacement unit A2 from the main body 2 is completed. Note that the attachment of the replacement unit A2 to the main body 2 is the reverse of the procedure for removing the replacement unit A2 from the main body 2, and thus the description thereof is omitted.

  As described above, in the image forming apparatus 1, the developing unit U2 and the developer container B2 are simultaneously replaced. Therefore, it is preferable that the time required for the developer container B2 to be filled with the developer is longer than the lifetime of the developer unit U2. Thus, after the developing unit U2 is used up to the end of its life, the developing unit U2 and the developer container B2 can be exchanged.

(effect)
According to the image forming apparatus 1 configured as described above, it is possible to reduce the frequency of downtime during which printing is interrupted. More specifically, in the image forming apparatus described in Patent Document 1, when the waste powder collection container is replaced, printing is interrupted, resulting in downtime. In the image forming apparatus, when the developing device deteriorates, the developing device is replaced. For this reason, since the printing is interrupted when the developing device is replaced, downtime occurs. Further, in the image forming apparatus, when the photosensitive drum is deteriorated, the photosensitive unit is replaced. As a result, printing is interrupted when the photosensitive unit is replaced, resulting in downtime. As described above, in the image forming apparatus described in Patent Document 1, downtime occurs at three types of timing.

  On the other hand, in the image forming apparatus 1, the photosensitive unit U1 and the toner storage container B1 are integrated to constitute an exchange unit A1. Then, by replacing the replacement unit A1, the photosensitive unit U1 and the toner container B1 are replaced at the same time. Similarly, the developing unit U2 and the developer container B2 are integrated to constitute an exchange unit A2. Then, by replacing the replacement unit A2, the developing unit U2 and the developer container B2 are simultaneously replaced. Therefore, in the image forming apparatus 1, downtime occurs only at two types of timing. As a result, the image forming apparatus 1 can reduce the frequency of downtime as compared with the image forming apparatus described in Patent Document 1.

  In the image forming apparatus 1, since the photosensitive unit U1 and the toner container B1 are simultaneously replaced, the toner container B1 is not removed from the photosensitive unit U1. Therefore, when the toner container B1 is replaced, the toner is prevented from leaking from the joint portion between the toner container B1 and the photosensitive unit U1.

  Further, in the image forming apparatus 1, since the developer unit U2 and the developer container B2 are simultaneously replaced, the developer container B2 is not detached from the developer unit U2. Therefore, when the developer container B2 is replaced, the developer is prevented from leaking from the joint between the developer container B2 and the developing unit U2.

  In the image forming apparatus 1, the time required for the toner storage container B1 to be filled with toner is longer than the life of the photosensitive unit U1. As a result, the photoconductor unit U1 and the toner container B1 can be replaced after the photoconductor unit U1 has been used up to the end of its life.

  In the image forming apparatus 1, the time required for the developer container B2 to be filled with the developer is longer than the life of the developer unit U2. Thus, after the developing unit U2 is used up to the end of its life, the developing unit U2 and the developer container B2 can be exchanged.

  In the image forming apparatus 1, it is possible to suppress a decrease in strength of the main body frame in the main body 2. More specifically, in the developing unit U2 adopting the trickle developing method, as shown in FIG. 2, since the discharge spaces Sp3 and Sp4 are provided, the length of the developing unit U2 in the y-axis direction is long. Become. On the other hand, it is required to reduce the width of the main body 2 in the y-axis direction. Therefore, as shown in FIG. 2, in the image forming apparatus 1, the developing unit U <b> 2 passes through a main body frame made of a metal plate provided in the main body 2. Accordingly, when the replacement unit A2 including the developing unit U2 is detachable from the door on the positive side in the x-axis direction, a larger hole is provided in the main body frame on the positive direction side in the x-axis direction than the replacement unit A2. There is a need. As a result, the strength of the main body frame is reduced.

  Therefore, in the image forming apparatus 1, the replacement unit A2 is attached to and detached from the main body 2 by being moved in the y-axis direction. Accordingly, the main body frame in the main body 2 only needs to be provided with a hole having a shape when the replacement unit A2 is viewed in plan from the positive side in the y-axis direction. As a result, a decrease in strength of the main body frame of the main body 2 is suppressed.

  Further, in the image forming apparatus 1, the photosensitive drum 7 and the developing roller 10 are prevented from being damaged when the replacement unit A1 is replaced. More specifically, the developing roller 10 is in pressure contact with the photosensitive drum 7. Therefore, when the replacement unit A1 is removed, if the replacement unit A1 is moved to the positive side in the x-axis direction while the developing roller 10 is in pressure contact with the photosensitive drum 7, the photosensitive drum 7 and the developing roller 10 are removed. Drag between them. As a result, the photosensitive drum 7 and the developing roller 10 may be damaged.

  Therefore, in the image forming apparatus 1, the replacement unit A <b> 1 is moved in the direction in which the developing roller 10 is in pressure contact with the photosensitive drum 7, and after the developing roller 10 and the photosensitive drum 7 are separated, the x-axis direction is changed. Is removed from the main body 2. Thus, no drag is generated between the photosensitive drum 7 and the developing roller 10 when the replacement unit A1 is removed. As a result, the image forming apparatus 1 prevents the photosensitive drum 7 and the developing roller 10 from being damaged when the replacement unit A1 is replaced.

  Further, in the image forming apparatus 1, the photosensitive drum 7 and the developing roller 10 are prevented from being damaged when the replacement unit A1 is replaced for the following reason. More specifically, when the replacement unit A2 is pulled out to the positive side in the y-axis direction while the developing roller 10 is in pressure contact with the photosensitive drum 7, drag occurs between the photosensitive drum 7 and the developing roller 10. To do. As a result, the photosensitive drum 7 and the developing roller 10 may be damaged. Therefore, in the image forming apparatus 1, the replacement unit A2 cannot be removed from the main body 2 when the replacement unit A1 is attached to the main body 2. As a result, the replacement unit A1 is not pulled out to the positive side in the y-axis direction with the developing roller 10 in pressure contact with the photosensitive drum 7. As a result, the image forming apparatus 1 prevents the photosensitive drum 7 and the developing roller 10 from being damaged when the replacement unit A1 is replaced.

  In the image forming apparatus 1, the main body 2 can be downsized. More specifically, when both of the replacement units A1 and A2 are removed from the main body 2 through the door on the positive side in the y-axis direction, the pressure contact between the photosensitive drum 7 and the developing roller 10 is released. A mechanism is required. Therefore, the main body 2 is enlarged.

  On the other hand, in the image forming apparatus 1, the replacement unit A1 is removed from the main body 2 via the door on the positive side in the x-axis direction. For this reason, when the replacement unit A1 is moved to the positive side in the x-axis direction, the pressure contact between the photosensitive drum 7 and the developing roller 10 is automatically released. Therefore, the image forming apparatus 1 does not require a mechanism for releasing the pressure contact between the photosensitive drum 7 and the developing roller 10. As a result, the main body 2 can be reduced in size.

(Other embodiments)
The image forming apparatus according to the present invention is not limited to the image forming apparatus 1 according to the above-described embodiment, and can be changed within the scope of the gist thereof.

  In the image forming apparatus 1, the toner image is directly transferred from the photosensitive drum 7 to the sheet. However, the toner image may be secondarily transferred to the sheet after being primarily transferred from the photosensitive drum 7 to the intermediate transfer belt. . In this case, the intermediate transfer belt is a transfer target.

  The image forming apparatus 1 forms a monochrome toner image, but may form a color toner image.

  As described above, the present invention is useful for an image forming apparatus, and is particularly excellent in that the frequency of downtime during which printing is interrupted can be reduced.

A1, A2 exchange unit B1 toner container B2 developer container U1 photoconductor unit U2 developer unit 1 image forming device 7 photoconductor drum 9 optical scanning device 10 developing roller 11 supply screw 12, 34 stirring screw 13, 30, 32 40 Main body 14 Transfer roller 15 Cleaner 18, 31, 33, 42 Conveying screw 19 Eraser 20 Fixing device

Claims (9)

A first unit including a latent image carrier that carries an electrostatic latent image;
A toner container configured integrally with the first unit;
A trickle development system that contains a developer composed of toner and a carrier and discharges a part of the contained developer, by applying toner to the latent image carrier. A second unit for developing the electrostatic latent image to form a toner image by:
A developer containing container configured to be integrated with the second unit and containing the developer discharged by the second unit;
Transfer means for transferring the toner image from the latent image carrier to a transfer target;
A main body that houses the first unit, the toner container, the second unit, the developer container, and transfer means;
With
The first unit further includes recovery means for recovering toner remaining on the latent image carrier after transfer of the toner image.
The toner storage container stores the toner recovered by the recovery means,
The first unit and the toner container, and the second unit and the developer container are detachable from the main body;
An image forming apparatus. The first unit and the toner container are attached to and detached from the main body by being moved in a horizontal direction perpendicular to a rotation axis of the latent image carrier;
The image forming apparatus according to claim 1. The second unit includes a developer carrier that is in pressure contact with the latent image carrier and imparts toner to the latent image carrier,
The first unit is moved in a direction in which the developer carrier is in pressure contact with the latent image carrier, and after the developer carrier and the latent image carrier are separated, Being removed from the main body by being moved in a horizontal direction perpendicular to the rotation axis of the latent image carrier;
The image forming apparatus according to claim 2. The image forming apparatus includes:
A fixing device provided on the upper side of the first unit and fixing the toner image to the transfer target;
In addition,
The first unit is provided on the upper side of the second unit,
The toner container is provided on the upstream side of the first unit in the removing direction when the first unit and the toner container are attached and detached.
The vertical length of the upstream portion of the first unit in the removal direction with respect to the latent image carrier and the vertical length of the toner container are determined by the fixing device and the vertical unit in the vertical direction. Shorter than the opening width between the second unit,
The image forming apparatus according to claim 2, wherein the image forming apparatus includes: The second unit and the developer container are attached to and detached from the main body by being moved in a direction in which a rotation shaft of the latent image carrier extends.
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The image forming apparatus includes:
Neutralizing means for neutralizing the latent image carrier after transferring the toner image;
In addition,
The static elimination means is retracted so as not to hinder the removal of the first unit from the main body;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The time required for the toner container to be filled with toner is longer than the lifetime of the first unit;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The time required for the developer container to be filled with developer is longer than the lifetime of the second unit;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The second unit and the developer container can not be removed from the main body when the first unit and the toner container are attached to the main body;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.

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