JP5550466B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic image forming apparatus and a process cartridge that can be attached to and detached from the electrophotographic image forming apparatus.

  Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming system. Examples of the electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED printer, etc.), a facsimile machine, a word processor, and the like.

  The process cartridge is a cartridge in which a charging unit, a developing unit or a cleaning unit and an image carrier are integrally formed, and the cartridge can be attached to and detached from the main body of the electrophotographic image forming apparatus. Further, it means that at least the charging means and the image carrier are integrally formed into a cartridge that can be attached to and detached from the apparatus main body.

  Conventionally, in an electrophotographic image forming apparatus using an electrophotographic image forming process, the electrophotographic photosensitive member and the process means acting on the electrophotographic photosensitive member are integrally formed into a cartridge. A process cartridge system is employed in which the cartridge can be attached to and detached from the main body of the electrophotographic image forming apparatus. According to this process cartridge system, the maintenance of the apparatus can be performed by the user himself / herself without depending on the service person, so that the operability can be remarkably improved. In the above method, since the user replaces the process cartridge, it is necessary to improve the visibility of the grip portion of the process cartridge at the time of replacement and the operability at the time of replacement.

  An image forming apparatus configured such that a plurality of process cartridges are mounted so as to have a step in the height direction with respect to each adjacent process cartridge is known (for example, Patent Document 1). These process cartridges are provided with a grip portion for gripping the image forming apparatus when it is attached or detached. Conventionally, when a process cartridge is mounted on an image forming apparatus, the steps of adjacent process cartridges and the steps of the gripping portions have the same size. When the level difference of the gripping portion is large, it may be difficult for the user to visually recognize the position of the gripping portion of the process cartridge when performing the attaching / detaching operation.

JP 2008-170961 A (9th page, FIG. 1)

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that improves the visibility of a grip portion of a process cartridge and improves the operability during attachment / detachment. is there.

  A typical configuration related to the present invention for achieving the above object is an image forming apparatus for forming an image on a recording medium, wherein a plurality of cartridges are detachably attached to a main body of the image forming apparatus, A plurality of cartridges mounted on the apparatus main body at different heights in the height direction of the apparatus main body, and a plurality of the cartridges gripped when the cartridge is attached to and detached from the apparatus main body along the longitudinal direction of the cartridge. Each of the gripping portions provided in each of the adjacent cartridges so as to have a step smaller than the step in the height direction of the adjacent cartridges. .

  By using the above configuration, the step of the grip portion can be made smaller than the step of the cartridge. As a result, it is possible to improve the visibility of the grip portion when the cartridge is mounted on the image forming apparatus, and to improve the operability when attaching and detaching.

1 is an overall configuration diagram of an image forming apparatus. FIG. 6 is a cross-sectional explanatory view of a process cartridge. 3 is a perspective view illustrating a state before the process cartridge 7 is mounted on the image forming apparatus main body 100. FIG. It is explanatory drawing which shows arrangement | positioning of a process cartridge and a holding part. It is explanatory drawing which shows that there is no level | step difference in a holding part. It is composition explanatory drawing which can change the attachment position of a holding part.

Example 1
The first embodiment of the present invention will be described below. FIG. 1 shows the overall configuration of a full-color laser beam printer as an example of an image forming apparatus.

  As shown in FIG. 1, the image forming apparatus main body 100 includes four photosensitive drums 1 (1a, 1b, 1c, 1d) as image bearing members provided side by side with respect to the horizontal direction. . The photosensitive drum 1 is rotationally driven in a clockwise direction in FIG. 1 by driving means (not shown). Around the photosensitive drum 1, a charging device 2, a scanner unit 3, a developing device 4, an electrostatic transfer device 5, a cleaning member 6 and the like are arranged in order according to the rotation direction. The charging device 2 (2a, 2b, 2c, 2d) is a device that is provided on the outer peripheral surface of the photosensitive drum 1 as an image carrier and uniformly charges the photosensitive layer.

  The charging device 2 is a conductive roller as a primary charging unit formed in a roller shape. The conductive roller is brought into contact with the surface of the photosensitive drum 1 and the surface of the photosensitive drum 1 is uniformly charged by applying a charging bias voltage to the conductive roller.

  The scanner unit 3 (3a, 3b, 3c, 3d) as a latent image forming unit is a unit that forms an electrostatic latent image on the photosensitive drum 1 by irradiating a laser beam based on image information. In other words, the scanner unit 3 selectively exposes the surface of the charged photosensitive drum 1 with laser light corresponding to an image signal, for example, by a laser diode (not shown), to thereby form an electrostatic latent image. It is a unit that forms. The scanner unit 3 as a latent image forming unit that forms an electrostatic latent image on the charging surface of the photosensitive drum 1 is provided below the photosensitive drum 1 in the gravitational direction. The developing device 4 (4a, 4b, 4c, 4d) develops the toner supplied to the developing roller 25 (25a, 25b, 25c, 25d) by attaching it to the electrostatic latent image on the surface of the photosensitive drum 1, It is a device for visualizing.

  The electrostatic transfer device 5 is a device that transfers a toner image on the photosensitive drum 1 to a transfer material M that is a recording medium. The cleaning member 6 (6a, 6b, 6c, 6d) removes the transfer residual toner remaining on the surface of the photosensitive drum 1 after the transfer. In FIG. 1, the electrostatic transfer device 5 is illustrated as an intermediate transfer unit including an intermediate transfer body and a casing related thereto.

  The photosensitive drum 1 as the image carrier, the charging device 2 as the charging unit, the developing device 4 and the cleaning member 6 are integrally formed into a cartridge, and the process cartridge 7 (7a, 7b, 7c, 7d). Is configured. The process cartridge 7 is configured to be detachable from the apparatus main body of the image forming apparatus 100 in the longitudinal direction of the process cartridge 7.

  The electrostatic transfer device 5 is provided with an intermediate transfer belt 9 that circulates and moves so as to face and face all the photosensitive drums 1a, 1b, 1c, and 1d. The toner images on the photosensitive drums 1a, 1b, 1c, and 1d are sequentially primary-transferred onto the intermediate transfer belt 9 sequentially. The toner image transferred onto the intermediate transfer belt 9 circulates counterclockwise in FIG. 1 and is transferred onto the transfer material M by the secondary transfer roller 70. The four primary transfer rollers 58 (58a, 58b, 58c, 58d) are in contact with the inner side of the intermediate transfer belt 9, and are respectively positioned at positions facing the four photosensitive drums 1a, 1b, 1c, 1d. It is installed side by side. A positive polarity bias is applied to these primary transfer rollers 58 during transfer, and positive polarity charges are applied to the intermediate transfer belt 9. The negative polarity toner image on the photosensitive drum 1 is transferred onto the intermediate transfer belt 9 in contact with the photosensitive drum 1 by the electric field generated at this time.

  Here, a plurality of transfer materials M are stored in the paper feed cassette 17. The transfer material M in the paper feed cassette 17 is separated and fed one by one and conveyed to the secondary transfer roller 70. The fixing unit 74 includes a rotating heating roller 74a and a pressure roller 74b that presses against the rotating roller 74 and applies heat and pressure to the transfer material M. The transfer material M to which the toner image on the photosensitive drum 1 is transferred is conveyed by the pressure roller 74b when passing through the fixing unit 74, and is given heat and pressure by the heating roller 74a. It is fixed on the surface of the transfer material M. After the toner image is thermally fixed by the fixing unit 74, the transfer material M is discharged out of the main body by the paper discharge roller 72.

(Process cartridge configuration)
Next, a process cartridge according to an embodiment of the present invention will be described. FIG. 2 shows a main cross section of the process cartridge 7. The process cartridge 7a containing yellow toner, the process cartridge 7b containing magenta toner, the process cartridge 7c containing cyan toner, and the process cartridge 7d containing black toner have the same configuration. .

  As shown in FIG. 2, the process cartridge 7 according to the first embodiment is divided into a drum unit 26 and a developing device 4.

  The drum unit 26 is provided with a charging roller 2 as a primary charging unit on the periphery of the photosensitive drum 1. The drum unit 26 includes a flexible sheet member 28 that seals residual transfer toner between the photosensitive drum 1 and the cleaning frame 27, so-called waste toner leakage, and waste remaining on the surface of the photosensitive drum 1. A cleaning member 6 for removing toner is provided. The waste toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 is accommodated in a waste toner chamber 27 a provided in the cleaning frame 27.

  The container support structure of the developing device 4 is a fishing structure that is swingably supported with respect to the drum unit 26. That is, the coupling holes 12 provided at both ends of the developing device 4 and the support holes 13 provided at both ends of the cleaning frame 27 of the drum unit 26 are aligned, and pins are inserted from both ends of the drum unit 26. Further, in the developing device 4, the developing roller 25 is in contact with the photosensitive drum 1 by being always biased by the pressure spring 38 to rotate around the support hole 13.

  The developing device 4 includes a developing frame 31, a developing roller 25 that contacts the photosensitive drum 1 and rotates in the direction of arrow A, and a toner conveying member that conveys toner stored in the toner storing portion 31 a to the developing portion. 36 is provided. A toner supply roller 34 that rotates in the direction of arrow B in contact with the developing roller 25 and a developing blade 35 for thinning the toner are disposed on the circumference of the developing roller 25.

  As the developing roller 25 rotates, the toner applied on the developing roller 25 is conveyed to a developing unit where the photosensitive drum 1 and the developing roller 25 face each other. Here, the developing part is a part where the photosensitive drum 1 and the developing roller 25 are in contact with each other. In the developing unit, the toner on the developing roller 25 is attached to the electrostatic latent image formed on the surface of the photosensitive drum 1 by a developing bias applied from a power source (not shown). Thereby, the electrostatic latent image is developed and visualized. Here, the toner remaining on the surface of the developing roller 25 without contributing to the development of the electrostatic latent image is returned to the developing device and collected as the developing roller 25 rotates.

(Installation structure of the process cartridge to the image forming apparatus main body)
Next, a mounting configuration for mounting the process cartridge according to the present embodiment to the image forming apparatus main body will be described with reference to FIG.

  FIG. 3 is a perspective view illustrating a state before the process cartridge 7 is attached to the image forming apparatus main body 100. In the present embodiment, the process cartridge 7 is attached to the image forming apparatus main body 100 by holding the holding portions 24 (24 a to 24 d) provided in the drum unit 26. The process cartridge 7 is inserted in the direction of arrow C, which is a direction parallel to the axial direction of the photosensitive drum 1, that is, from the front side to the back side in FIG. Thus, the process cartridge 7 can be attached to and detached from the image forming apparatus main body 100.

  In FIG. 3, an openable / closable door 121 is provided on the front side of the image forming apparatus main body 100. When the door 121 is opened, the mounting portions 122 (122a to 122d) of the four process cartridges 7 (7a to 7d) arranged side by side with respect to the horizontal direction are exposed. An upper mounting guide 180 (180a to 180d) and a lower mounting guide 181 (181a to 181d) extending from the front side to the back side of the image forming apparatus main body 100 are provided on the upper side and the lower side of each mounting unit 122, respectively. It has been. Then, the upper guide portion 129 and the lower guide portion 130 provided on the drum unit 26 of the process cartridge 7 are engaged with the upper mounting guide 180 and the lower mounting guide 181 of the image forming apparatus main body 100, respectively, and an arrow C in the figure. Push in the direction.

  Then, when the process cartridge 7 is inserted to a predetermined position, the positioned portions 140a and 150a on the back side and the near side of the process cartridge 7 are positioned on the image forming apparatus main body 100, and the mounting of the process cartridge 7 is completed. To do.

(Grip arrangement)
As an example of this embodiment, FIG. 4 shows the arrangement of the process cartridge 7 and the grip portion 24 when mounted on the image forming apparatus. The process cartridge 7 is mounted on the image forming apparatus with a step in the height direction with respect to the horizontal direction. In the present embodiment, the gripping portions 24 are arranged so that the steps of the gripping portions 24 are smaller than the steps of the adjacent process cartridges 7. When arranged in this way, the step E of the gripping portions 24a to 24d becomes smaller than the step D of the process cartridges 7a to 7d.

  As a result, when mounted on the image forming apparatus, the step of the grip portion 24 becomes smaller than the step of the process cartridge 7, and the user can easily see the position of the grip portion 24, thereby improving the operability when attaching and detaching.

  In this embodiment, the grip portion 24 is provided in the drum unit 26, but it may be provided in either the drum unit 26 or the developing device 4.

  As shown in FIG. 5, the visibility of the grip portion 24 and the operability at the time of attachment / detachment are further improved by arranging the grip portions 24a to 24d so that there is no step E when the image forming apparatus is mounted. be able to.

  Here, FIG. 6 shows a configuration explanatory diagram of the process cartridge 7 configured so that the attachment position of the grip portion 24 to the process cartridge 7 can be changed. As a configuration, the gripping portion 24 is attached to the attachment hole 23 (23a, 23b, 23c, 23d) with the screw 40 with respect to the cleaning frame 27. By enabling the attachment position of the grip portion 24 to be changed, the position of the grip portion 24 can be changed to a position that is easy for the user to operate.

  The frame of the process cartridge 7 may be either the cleaning frame 27 or the developing frame 31.

  By making it possible to change the attachment position of the gripping part 24 as in the above configuration, it is easy to arrange the gripping part 24 so that the level difference of the gripping part 24 is smaller than the level difference of the process cartridge 7.

  As described above, in this embodiment, the process cartridge has been described. However, it may be a cartridge for supplying the developer to the process cartridge.

M Recording medium 1 (1a to 1d) Photosensitive drum 2 (2a to 2d) Charging roller 3 Scanner unit 4 (4a to 4d) Developing device 5 Electrostatic transfer device 6 (6a to 6d) Cleaning member 7 (7a to 7d) Process cartridge 9 Intermediate transfer belt 12 Coupling hole 13 Support hole 17 Cassette 23 (23a to 24d) Mounting hole 24 (24a to 24d) Grip part 25 (25a to 25d) Developing roller 26 (26a to 26d) Drum unit 27 Cleaning frame 27a Waste toner chamber 28 Flexible sheet member 31 Developing frame 31a Toner storage portion 34 Toner supply roller 35 Developing blade 36 Toner transport member 38 Pressure spring 40 Screw 46 Charging roller pressure member 58 (58a-d) Primary transfer roller 70 Secondary transfer roller 72 Paper discharge roller 74 Fixing section 74 Heating roller 74b pressing roller 100 image forming apparatus 121 door 122 (122a to 122d) mounting portion 129 to be the upper guide portion 130 to be lower guides 140a portion to be positioned (the back side)
150a Positioned part (front side)
180 (180a to 180d) Wearing upper guide 181 (181a to 181d) Wearing lower guide

Claims (3)

In an image forming apparatus for forming an image on a recording medium,
A plurality of cartridges detachably mounted on the apparatus main body of the image forming apparatus, the cartridges mounted on the apparatus main body at different heights in the height direction of the apparatus main body;
A gripping portion provided in each of the plurality of cartridges, which is gripped when the cartridge is attached to and detached from the apparatus main body along the longitudinal direction of the cartridge, and is higher than a step in the height direction of the adjacent cartridges. A grip portion provided in each of the adjacent cartridges so as to be a small step, and
An image forming apparatus comprising:   The image forming apparatus according to claim 1, wherein there is no step between the grip portions provided in adjacent cartridges.   The image forming apparatus according to claim 1, wherein the grip portion can change an attachment position in the height direction with respect to the cartridge.

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