JP5038213B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile.

  In recent electrophotographic image forming apparatuses, toner is used as a developer, so that toner is scattered in the image forming apparatus and dust and dust are floating. The optical unit of the image forming apparatus dislikes toner, dust, dust and the like. For this reason, the inside of the optical unit is hermetically sealed so that toner, dust, dust and the like do not enter the inside of the optical unit. The image forming apparatus has an opening through which a laser emitted from the optical unit passes. In order to prevent toner, dust, dust and the like from entering the optical unit, the opening has a cover glass through which the laser can pass.

  In such a configuration, if toner, dust, or dust that falls or floats from the developing unit into the image forming apparatus adheres to the cover glass and blocks the optical path of exposure, the density of the printed image is reduced or the image is lost. Therefore, a user or a service person accesses the inside of the image forming apparatus main body and cleans the cover glass with a soft cloth or the like so that toner, dust, dust or the like does not adhere to the cover glass. However, since the opening having the cover glass has a small opening area and must be cleaned so as not to damage the cover glass surface, it has been difficult to clean.

  Therefore, Patent Document 1 (Japanese Patent Laid-Open No. 2005-246901) proposes a cleaning configuration that can remove toner, dust, dust, and the like adhering to the cover glass. Specifically, a configuration in which the toner, dust, dust, etc. attached to the cover glass can be removed by sliding the cleaning member provided in the optical scanning device along the cover glass by the user or service person. is doing.

JP 2005-246901 A

  In the above-mentioned Patent Document 1, in the configuration in which the cleaning member is slid to clean the cover glass, it is necessary for the user or service person to move the cleaning member, and the cleaning operation is troublesome. The present invention is a further development of the above-described prior art, and cleans the cover glass in conjunction with the mounting operation of the cartridge. Furthermore, the present invention provides an image forming apparatus capable of easily releasing the engagement between the cartridge and the cleaning member when the cartridge is set at the image forming position after cleaning, and improving the operability when inserting the cartridge. For the purpose.

  In order to solve the above problems, a typical configuration of an image forming apparatus according to the present invention includes a rotatable image carrier that carries a toner image, and the image is formed by being inserted into and removed from the rotation axis of the image carrier. A cartridge detachable from the apparatus main body; an optical unit including a long transmissive member through which light emitted toward the image carrier is transmitted; and the image carrier for cleaning the transmissive member. In the image forming apparatus, comprising: a cleaning member that is movable along a longitudinal direction of the transmission member that substantially coincides with the rotation axis direction; and a latch member that presses the cartridge toward the image forming position. During operation, the cleaning member engages with the cartridge and moves along the longitudinal direction of the transmission member to clean the transmission member, and the cleaning member finishes cleaning the transmission member. After that, when the further inserted cartridge hits the latch member, the cleaning member is moved by the movement of the abutted latch member, and the engagement between the cleaning member and the cartridge is released. Features.

  According to the present invention, the cleaning member can be reliably engaged with the cartridge during cleaning, and when the cleaning is completed and the cartridge is set at the image forming position, the engagement between the cartridge and the cleaning member can be easily released. The operability when inserting can be improved.

  An embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. The dimensions, materials, relative arrangements, and the like of the components described in the present embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified.

[Image forming apparatus]
The overall configuration of the image forming apparatus will be outlined. FIG. 1 is a configuration diagram of an image forming apparatus according to the present embodiment.

  As shown in FIG. 1, a color laser printer 100 that is an image forming apparatus includes a process cartridge 7, a feeding device 13, a fixing unit 14, and a secondary transfer unit 15.

  In the process cartridge 7 (7a, 7b, 7c, 7d), the developing unit (developing unit) 4 and the cleaner unit 5 are integrally formed into a cartridge. The process cartridge 7 can be attached to and detached from the color laser printer 100 in the longitudinal direction of the image carrier. The four process cartridges 7 have the same structure, but differ in that they form images with toners of different colors, that is, yellow (Y), magenta (M), cyan (C), and black (Bk). Yes.

  The developing units 4a to 4d include developing rollers 24a, 24b, 24c, and 24d, developer application rollers 25a, 25b, 25c, and 25d, and a toner container.

  The cleaner units 5a to 5d have photosensitive drums 1a to 1d as image carriers, charging rollers 2a to 2d as charging means, cleaning blades 8a to 8d as cleaning means, and waste toner containers.

  Around each photosensitive drum 1, a charging roller 2, an optical unit 3, a developing unit 4, an intermediate transfer belt unit 12, and a drum cleaning blade 8 are arranged in order according to the rotation direction.

  The photosensitive drums 1a to 1d are configured by applying an organic photoconductive layer (OPC) to the outer peripheral surface of an aluminum cylinder. Both ends of the photosensitive drum 1 are rotatably supported by flanges, and a driving force is transmitted to one end from a driving motor (not shown) in the arrow direction (clockwise direction) in FIG. Driven by rotation.

  The charging means 2a to 2d are conductive rollers formed in a roller shape. The charging unit 2 is brought into contact with the surfaces of the photosensitive drums 1a to 1d, and a charging bias voltage is applied by a power source (not shown) to uniformly charge the surface of the photosensitive drum 1.

  The optical unit 3 is arranged below the process cartridges 7 a to 7 d in the vertical direction, performs exposure based on image signals to the photosensitive drums 1 a to 1 d, and forms an electrostatic latent image on the photosensitive drum 1.

  With the above-described configuration, the photosensitive drums 1a to 1d are charged to a predetermined negative potential by the charging rollers 2a to 2d, and then electrostatic latent images are formed by the optical unit 3, respectively. The electrostatic latent images are reversely developed by the developing units 4a to 4d, and negative toner is attached to form Y, M, C, and Bk toner images, respectively.

  In the intermediate transfer belt unit 12, an intermediate transfer belt 12e is stretched around a drive roller 12f and a tension roller 12g, and the tension roller 12g applies tension in the direction of arrow E. Further, primary transfer rollers 12a, 12b, 12c, and 12d are disposed inside the intermediate transfer belt 12e so as to face the respective photosensitive drums 1a to 1d, and a transfer bias is applied by a bias applying unit (not shown). It has a configuration.

  Each photosensitive drum rotates in the arrow direction, the intermediate transfer belt 12e rotates in the arrow F direction, and a positive bias is applied to the primary transfer rollers 12a to 12d. Thus, the toner images on the photosensitive drum 1a are sequentially transferred onto the intermediate transfer belt 12e, and are conveyed to the secondary transfer unit 15 in a state where the four color toner images are overlapped.

  The feeding device 13 includes a feeding roller 9 that feeds the sheet S from the inside of the feeding cassette 11 that stores the sheet S, and a conveyance roller pair 10 that conveys the fed sheet S.

  The sheets S stored in the feeding cassette 11 are pressed against the feeding roller 9, separated one by one by the separation pad 23 (friction piece separation method), and conveyed.

  Then, the sheet S conveyed from the feeding device 13 is conveyed to the secondary transfer unit 15 by the registration roller pair 17.

  In the secondary transfer unit 15, a four-color toner image on the intermediate transfer belt 12 e is secondarily transferred onto the conveyed sheet S by applying a positive bias to the secondary transfer roller 16. The fixing unit 14 serving as a fixing unit applies heat and pressure to the image formed on the transfer material and fixes the image.

  In the process where the sheet S is nipped and conveyed through the fixing nip N together with the fixing belt 14a, the unfixed toner image on the transfer material S is heated and fixed by heating with the heater heat in the fixing belt 14a. The fixed sheet S is discharged to the discharge tray 121 by the discharge roller pair 120.

  On the other hand, the toner remaining on the surfaces of the photosensitive drums 1a to 1d after the toner image transfer is removed by the cleaning blades 8a to 8d. The removed toner is collected in a waste toner container in the cleaner units 5a to 5d.

Further, the toner remaining on the intermediate transfer belt 12e after the secondary transfer to the sheet S is removed by the transfer belt cleaning device 122, and the removed toner passes through a waste toner conveyance path (not shown) and passes through the back of the device. The toner is collected into a waste toner collecting container (not shown) disposed on the surface. [Cleaning member 20]
FIG. 2 is a configuration diagram of the process cartridge 7, the optical unit 3, and the cleaning member 20. FIG. 3 is a configuration diagram of the cleaning member 20. FIG. 4 is a diagram showing a cleaning process.

  As shown in FIG. 2, the image forming apparatus main body has a stay member 32 forming a main body skeleton. The stay member 32 includes an opening hole 30 for forming an optical path of the optical unit 3, and a cartridge insertion guide 21 disposed in the vicinity of the opening hole 30. By inserting the insertion rib 22 formed integrally with the process cartridge 7 along the insertion guide 21, the process cartridge 7 can be easily attached to a predetermined position of the apparatus main body. When the process cartridge 7 is positioned on the apparatus main body, the boss (not shown) arranged on the process cartridge 7 is positioned by fitting into a hole (not shown) of the apparatus main body, and in this state, the insertion rib 22 and the insertion are inserted. The guide 21 is not in contact.

  In addition, a cover glass 31 as a transmissive member is disposed so as to cover the opening hole 30 so that foreign matters such as dust and toner that have passed through the opening hole 30 do not enter the inside of the optical unit, and the functional components inside the optical unit become dirty. To prevent image defects. The cover glass 31 transmits light from the optical unit 3 that exposes the photosensitive drum 1. Here, the cover glass 31 has a long shape, and in order to transmit light emitted toward the photosensitive drum 1, the rotation axis direction of the photosensitive drum 1 and the longitudinal direction of the long cover glass 31 are different. It arrange | positions so that it may correspond substantially.

  The printer 100 includes a cleaning member 20 that cleans the cover glass 31 by rubbing the surface (cleaning surface) of the cover glass 31. The cleaning member 20 includes a cleaning sheet 26, a wiping member 27, and a base member 28. The cleaning member 20 is mounted on the rail member 49 facing the cover glass 31 so as to be slidable in the longitudinal direction of the cover glass 31.

  The cleaning sheet 26 has flexibility. At the time of cleaning, the end of the cleaning sheet 26 comes into contact with the surface of the cover glass 31, and the cleaning sheet 26 moves to move the foreign matter.

  The wiping member 27 is disposed so that a part of the wiping member 27 abuts on the cover glass 31, and wipes off the foreign matter remaining on the surface of the cover glass 31 after moving the foreign matter with the cleaning sheet 26.

  As shown in FIG. 3, the contact angle formed when the cleaning sheet 26 and the cover glass 31 contact each other (the angle in the direction in which the cleaning member 20 advances during cleaning) is an obtuse angle, and is 135 ° in this embodiment. It is set. Accordingly, even a large amount of toner, dust, and dust can be reliably moved, and slipping through the cleaning sheet 26 can be minimized. If the contact angle formed between the cleaning sheet 26 and the cover glass 31 is too large, the contact cannot be made at the leading edge of the cleaning sheet 26. On the other hand, if the contact angle between the cleaning sheet 26 and the cover glass 31 is too small, the cleaning sheet 26 is turned over. In view of these occurrence phenomena, the angle is set to 135 ° to prevent both the cleaning failure of the cleaning sheet 26 and the turning of the cleaning sheet 26.

  The tip of the cleaning sheet 26 is in contact with the cover glass 31 in a bent state, and the wiping member 27 is in contact with the cover glass 31 in a state of being urged and crushed. In the present embodiment, a 100 μm thick polyester sheet is used as the cleaning sheet 26, and a 2 mm thick urethane foam having a hardness of about 100 N and a 1.5 mm thick polyester non-woven fabric are bonded as a wiping member 27 by a welding process. is doing. The cleaning sheet 26 is bent by 1 mm, and the wiping member 27 is crushed by 1 mm.

  During cleaning, the cleaning member 20 is moved in the direction of the arrow in FIG. 3 so that the tip of the cleaning sheet 26 moves foreign matter such as toner and dust on the cover glass 31, and the wiping member 27 cannot clean the cleaning sheet 26. Wipe off any foreign objects.

  The cleaning member 20 is interlocked with the insertion / extraction operation of the process cartridge 7 and the cleaning of the home position before the cleaning of one end of the rail member 49 (cleaning start position, position of FIG. 3A) and the cleaning of the other end of the rail member 49 is completed. It is possible to slide between the positions (positions in FIG. 3B).

  As shown in FIGS. 4 and 5, the cleaning member 20 has an engaging claw 40 above the base member 28 and in front of the cleaning direction. A cleaning member engaging portion 7 e is provided on the lower surface of the process cartridge 7. When the process cartridge 7 slides, the engaging portion 7e engages with the engaging claw 40, and the cleaning member 20 slides.

  As shown in FIGS. 5 to 7, a latch member 50 is provided in the vicinity of the other end of the rail member 49 (the back side in the cartridge insertion direction). The latch member 50 has a claw portion 50a and a tapered portion 50b. The latch member 50 is provided so as to be rotatable around the side opposite to the end provided with the claw portion 50a.

  On the other end of the rail member 49, a rib 49a is provided. The claw portion 50a can push down the rib 49a. A convex portion 7f is formed on the lower surface of the process cartridge 7 and on the front end in the insertion direction. By pushing in the mounting direction of the process cartridge 7, the convex portion 7f slides on the tapered portion 50b and is pressed to the image forming position over the tapered portion 50b.

(Operation of cleaning member)
The cleaning process will be described. FIG. 4 is a cross-sectional view showing a cleaning process of the cleaning member 20.

  In FIG. 4A, the cleaning member 20 is slidably mounted on the rail member 49, and is positioned at a home position (cleaning start position) before cleaning of one end of the rail member 49.

  A base guide urging member 35 is provided between the cover glass 31 and the rail member 49. The base guide biasing member 35 lifts the rail member 49 to a height at which the cleaning sheet 26 and the wiping member 27 are separated from the cover glass 31.

  In FIG. 4B, the process cartridge 7 is provided with a cleaning member engaging portion 7e. By inserting the process cartridge 7 into the color laser printer 100, the engaging portion 7e pushes down the cleaning member 20 (base member 28) against the urging force of the base guide urging member 35. The cleaning sheet 26 and the wiping member 27 are urged by the cover glass 31 to be in a cleanable state.

  When the process cartridge 7 is further inserted, the engaging portion 7e is engaged with the engaging claw 40 protruding from the upper portion of the cleaning member 20. Then, by further inserting the process cartridge 7, the engaging portion 7e pushes the engaging claw 40, the cleaning member 20 slides along the rail member 49, and the cleaning operation on the cover glass 31 is started.

  As the process cartridge 7 moves, the base member 28 moves in the traveling direction along the rail member 49, and the cleaning sheet 26 and the wiping member 27 move to the cleaning end position while cleaning the cover glass 31 and stop.

  As shown in FIG. 5A, the process cartridge 7 further inserted toward the back of the product abuts against the latch member 50 at the cleaning end position after the cleaning member 20 cleans the cover glass 31. Then, the process cartridge 7 gets over while pushing down the latch member 50. The latch member 50 is provided with a claw portion 50a.

  When the latch member 50 is pushed down as shown in FIG. 5B, the claw portion 50 a pushes down the rib 49 a provided at the rear side end of the rail member 49. As a result, the cleaning member 20 attached to the rail member 49 moves in a direction (lower side) away from the process cartridge 7. As the cleaning member 20 moves downward, the engagement between the cleaning member 20 and the process cartridge 7 is released.

  As shown in FIG. 6, when the process cartridge 7 is further inserted from the state in which the claw portion 50 a of the latch member 50 pushes down the rail member 49 and the engagement between the cleaning member 20 and the process cartridge 7 is released, Moving. At this time, the rail member 49 pushed down by the claw 50a of the latch member 50 returns to the original position, and the cleaning member 50 also moves in the direction approaching the process cartridge (upper side). However, since the process cartridge 7 has already moved upward, the distance from the cleaning member 20 is sufficiently separated and the image forming position is reached.

  The process cartridge 7 that has reached the image forming position is urged to the rear side and the upper side by the latch member 50.

  With the configuration described above, the engagement between the process cartridge 7 and the cleaning member 20 can be easily released when the process cartridge 7 is set at the image forming position, and the operability when the process cartridge 7 is inserted can be improved.

  In the present embodiment, the configuration for releasing the engagement between the cleaning member 20 and the process cartridge 7 has been described. However, the engagement is not completely released, the amount of engagement is reduced, and the engagement remaining due to the insertion locus of the process cartridge 7. It is also possible to adopt a configuration in which is released.

  In the present embodiment, the configuration in which the rail member 49 is pushed by the operation in which the latch member 50 is pushed down has been described, but the configuration is not limited thereto. Any configuration may be used as long as the position of the cleaning member 20 is moved by the movement of the latch member 50 accompanying the insertion operation of the process cartridge 7 such as the latch member 50 directly pressing the cleaning member 20.

1 is a configuration diagram of an image forming apparatus according to an exemplary embodiment. It is a block diagram which shows the optical unit, process cartridge, and cleaning member which concern on this embodiment. It is a block diagram of the cleaning member which concerns on this embodiment. It is sectional drawing which shows the cleaning process of the cleaning member which concerns on this embodiment. It is a figure which shows cancellation | release of engagement of the cleaning member and process cartridge which concern on this embodiment. It is a figure which shows cancellation | release of engagement of the cleaning member and process cartridge which concern on this embodiment.

Explanation of symbols

1 ... Photosensitive drum (image carrier)
3 ... Optical unit 7 ... Process cartridge 20 ... Cleaning member 31 ... Cover glass (transmission member)
49 ... Rail member 50 ... Latch member

Claims (3)

A rotatable image carrier that carries a toner image, a cartridge that is inserted in and removed from the image carrier in the direction of the rotation axis and is detachable from the image forming apparatus main body, and is emitted toward the image carrier. An optical unit including a long transmissive member that transmits light, and a cleaning that is movable along the longitudinal direction of the transmissive member that substantially matches the rotational axis direction of the image carrier to clean the transmissive member. In an image forming apparatus having a member and a latch member that urges the cartridge toward the image forming position,
During the insertion operation of the cartridge, the cleaning member engages with the cartridge and moves along the longitudinal direction of the transmission member to clean the transmission member,
After the cleaning member finishes cleaning the transmitting member, the further inserted cartridge hits the latch member, and the cleaning member differs from the longitudinal direction of the transmitting member due to the movement of the abutted latch member. An image forming apparatus, wherein the engagement between the cleaning member and the cartridge is released by being moved in a direction. The optical unit is disposed below a cartridge attached to the image forming apparatus,
The latch member is disposed on the back side in the insertion direction of the cartridge,
When the cartridge is inserted toward the image forming position and gets over the latch member, the latch member releases the engagement between the cartridge and the cleaning member by moving the cleaning member downward. And
The image forming apparatus according to claim 1, wherein the cartridge is pressed to the image forming position after overcoming the latch member. A rail member slidably attached to the cleaning member;
When the cartridge is inserted and gets over the latch portion, the latch member pushes down the rail member and moves the cleaning member downward, thereby disengaging the cartridge and the cleaning member. And
The image forming apparatus according to claim 2, wherein the cartridge is pressed to an image forming position after overcoming the latch member.

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