JP2006350164A - Process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process cartridge in which the deformation and breakage of components can be prevented since a drum protection member is not opened inadvertently even when an attitude is changed. <P>SOLUTION: In the process cartridge attachable/detachable to/from an electrophotographic image forming apparatus, the link member has: first and second contact parts for supporting the process cartridge in a first attitude where the process cartridge is made self-supported on an installation surface; and a receiving part for length regulation, in a part of the outside in a longitudinal direction. The developing device has: a third contact part as a rotation regulating part for the process cartridge with respect to the installation surface, in a second attitude where the developing device approaches the installation surface; and a link member length regulating part. The link member length regulating part is located on the front side from the receiving part viewed from the pulling-out direction of a toner seal member, and the receiving part and the link member length regulating part are overlapped in the range from the first attitude to the second attitude, viewed from the pulling-out direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a process cartridge that can be used in an electrophotographic image forming apparatus or the like.

  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 (for example, a laser beam printer, an LED printer, etc.), a facsimile machine, a word processor, and the like.

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

  A configuration is used in which a drum protecting member is used in a state where the process cartridge is not used, and the drum protecting member is opened in conjunction with mounting on the image forming apparatus. In order to interlock with the mounting to the image forming apparatus, a drum protection member having a link mechanism is also used.

  Some conventional techniques have been devised to keep the link member in a normal position when mounted on the image forming apparatus (see, for example, Patent Document 1).

In addition, there is a configuration that prevents the drum protection member from being inadvertently opened before the start of use of the process cartridge (see, for example, Patent Document 2).
Japanese Patent Laid-Open No. 11-174937 (page 11, FIG. 5) Japanese Patent Laid-Open No. 2000-056657 (page 9, FIG. 2)

  When the process cartridge is supported by the link member of the drum protection member, there is a possibility that the link member rotates and the drum protection member opens when the attitude of the process cartridge changes.

  In consideration of the case where a large force is applied in the direction of the rotation axis of the link member, it is necessary to design the periphery of the rotation shaft firmly so that the link member is not deformed or damaged.

  The present invention has been made in view of the above problems, and the object of the process is to provide a process cartridge that can prevent the drum protection member from being inadvertently opened even if the posture is changed, and to prevent deformation and breakage of parts. It is to provide.

In order to achieve the above object, according to the present invention, a drum protection member and a link member are rotatably held by a developing device, and the link member supports the weight of the process cartridge while the process cartridge is self-supporting on an installation surface. In the process cartridge that is detachable from the electrophotographic image forming apparatus,
The link member is
First and second contact portions for supporting the process cartridge in a first posture in which the process cartridge is self-supporting on an installation surface;
Here, the second contact portion has a larger radius of rotation than the first contact portion, and has a longitudinal restriction receiving portion on a part of the outer side in the longitudinal direction,
The developing device includes:
A third contact portion that is a rotation regulating portion of the process cartridge with respect to the installation surface in a second posture in which the upper surface of the developing device is pressed vertically downward and the developing device approaches the installation surface;
A link member longitudinal restriction portion,
The link member longitudinal restriction portion is
The toner supply part to the developing means is detachably sealed so that the toner seal member is in front of the receiving part when viewed from the drawing direction, and in the range from the first attitude to the second attitude, The link member longitudinal restriction portion overlaps when viewed from the drawing direction.

  According to the present invention, even if the posture of the process cartridge changes, the drum protection member does not open carelessly.

  By receiving the force that the link member receives from the installation surface when the toner seal is pulled out, the longitudinal restriction portion of the toner frame body can reduce the moment to the link member support shaft and prevent deformation and breakage of the parts.

  Exemplary embodiments of the present invention will be described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. Absent. Further, the materials, shapes, etc. of the members once described in the following description are the same as those in the first description unless otherwise described.

  In the following description, the longitudinal direction of the process cartridge is a direction that intersects the direction in which the process cartridge is attached to and detached from the apparatus main body (a direction that is substantially orthogonal, the axial direction of the image carrier) and is parallel to the surface of the recording medium. And a direction intersecting (substantially orthogonal to) the conveyance direction of the recording medium. The left and right are left or right when the recording medium is viewed from above according to the conveyance direction of the recording medium. In addition, the upper surface of the process cartridge is a surface located above when the process cartridge is mounted on the apparatus main body, and the lower surface is a surface located below.

(Overall description of electrophotographic image forming apparatus)
First, an overall configuration of an electrophotographic image forming apparatus (hereinafter referred to as “image forming apparatus”) will be schematically described with reference to FIG. FIG. 2 is a schematic cross-sectional view of an image forming apparatus equipped with a process cartridge according to the present embodiment. More specifically, FIG. 2 is a schematic cross-sectional view of a laser beam printer which is one form of the image forming apparatus.

  As shown in FIG. 2, the image forming apparatus (laser beam printer) A according to the present embodiment transmits information light based on image information from an optical system 1 as an optical means to a drum-shaped electrophotographic photosensitive member (image carrier). And an electrostatic latent image is formed on the photosensitive drum 7. The electrostatic latent image is developed with a developer (hereinafter referred to as “toner”) to form a toner image. In synchronism with the formation of the toner image, the recording medium (for example, recording paper, OHP sheet, cloth, etc.) 2 is separated and fed one by one from the cassette 3a by the pickup roller 3b and the pressure contact member 3c that presses the recording medium. .

  The fed recording medium 2 is conveyed along a conveyance guide 3f1 to a transfer portion T where the photosensitive drum 7 of the process cartridge B and the transfer roller 4 as a transfer unit face each other.

  The recording medium 2 conveyed to the transfer portion T is transferred with the toner image formed on the photosensitive drum 7 by the transfer roller 4 to which voltage is applied, and is conveyed to the fixing unit 5 along the conveyance guide 3f2.

  The fixing unit 5 includes a driving roller 5a and a heater 5b, and includes a fixing rotating body 5d formed of a cylindrical sheet rotatably supported by a support 5c. The transferred toner image is fixed by applying pressure.

  The discharge roller 3d conveys the recording medium 2 on which the toner image is fixed, and discharges it to the discharge unit 6 through the reverse conveyance path. In this embodiment, the pickup means 3b, the pressure contact member 3c, the discharge roller 3d, etc. constitute the conveying means 3.

(Process cartridge)
Next, the overall configuration of the process cartridge will be schematically described with reference to FIG. FIG. 3 is a schematic cross-sectional view of the process cartridge according to the present embodiment.

  As shown in FIG. 3, the process cartridge B includes a photosensitive drum and at least one process means. Here, as the process means, for example, a charging means for charging the photosensitive drum, a developing means for developing the electrostatic latent image formed on the photosensitive drum, and a cleaning means for cleaning the toner remaining on the photosensitive drum. Etc.

  The process cartridge B according to the present embodiment rotates the photosensitive drum 7 having a photosensitive layer and applies a voltage to the charging roller 8 as a charging unit to uniformly charge the surface of the photosensitive drum 7. Information light (optical image) based on image information from the optical system 1 is exposed to the charged photosensitive drum 7 through the exposure opening 9b to form an electrostatic latent image on the surface of the photosensitive drum 7, and the static image is generated. The electrostatic latent image is developed by the developing device 10.

  The developing device (hereinafter referred to as “developing unit 10”) feeds the toner in the developer containing frame 10a, which is a toner containing portion, by a rotatable toner feeding member 10b. Then, the developing roller 10d, which is a developing rotator (developer carrying member) incorporating the fixed magnet 10c, is rotated, and a toner layer imparted with triboelectric charge is formed on the surface of the developing roller 10d by the developing blade 10e. The toner is transferred to the photosensitive drum 7 in accordance with the electrostatic latent image, thereby forming a toner image and making it visible.

  After the toner image is transferred to the recording medium 2 by applying a voltage having a polarity opposite to that of the toner image to the transfer roller 4, the toner remaining on the photosensitive drum 7 is scraped off by the cleaning blade 11a and the squeeze sheet 11b. Residual toner on the photosensitive drum 7 is removed by a cleaning means that scrapes and collects in the removed toner storage portion 11c.

  The process cartridge B according to the present embodiment rotatably supports the photosensitive drum 7, and includes a drum unit 11 including a drum frame 11d in which a cleaning blade 11a and a charging roller 8 are incorporated, a developing roller 10d, and toner. The developing unit 10 includes a developing frame 10f1 incorporating the chamber 10a.

  FIG. 4 shows an assembly diagram for explaining the developing unit.

  The developing frame 10f1 is rotatably supported with respect to the drum frame 11d so that the developing roller 10d can face the photosensitive drum 7 in parallel with a predetermined interval, and the developing roller 10d, the photosensitive drum 7, and the like. The spacers 10m for maintaining the distance between them are arranged at both ends of the developing roller 10d.

  End members 10g and 10h are provided on both side surfaces of the developing frame 10f1. The developing device frame 10f1 includes an arm portion formed with a coupling hole for rotatably suspending the developing unit 10 including the developing roller 10d on the drum unit 11 including the cleaning blade 11a. Further, a predetermined pressure is applied between the developing unit 10 and the drum unit 11 in order to maintain a gap.

  A toner frame 10f2 containing toner is coupled to the developing frame 10f1. The toner frame 10f2 incorporates toner conveying means for conveying toner, and supplies the toner to the developing roller 10d through the developing opening 10ha.

  Here, when the process cartridge is shipped, a sheet-like seal member 10f3 is detachably attached to the developing opening 10ha and sealed in order to eliminate the possibility of toner scattering. In order for the user to start using, the seal member 10f3 is peeled off by pulling out the seal handle 10f4 in the longitudinal direction, and an image can be formed.

  Next, as a configuration according to the present invention, the drum protection member 12 will be described with reference to FIG.

  The drum protection member 12 is provided to protect the photosensitive drum 7 in a state where the process cartridge is ejected from the image forming apparatus main body.

  An arm 14 as a link member that supports the drum protection member 12 and a wire 13 are attached to the developing unit 10. The arm 14 is attached by attaching a bearing portion 14 a provided on the arm 14 to the support shaft 15 of the developing unit 10. The tip end portion of the wire 13 is attached to the wire attachment portion 16 of the developing unit 10. Further, the wire 13 is rotatably attached to the drum protection member 12. Further, the drum protection member support shaft 14 b of the link member 14 is attached to the hole 12 a of the drum protection member 12. As a result, the drum protection member 12 can swing between the closed position for protecting the photosensitive drum and the open position during image formation.

  FIG. 6 is a perspective view showing a state in which the drum protection member is opened.

  The toner frame 10f2 has a length restricting portion 10f2a, and the arm 14 has a receiving portion 14c.

  The receiving portion 14c of the arm 14 is in the Y position in the drawing in the open state, and is in the Z position in the drawing in the state in which the link member is closed. When the user opens the toner seal 10f3 to start using the process cartridge, the process cartridge is outside the image forming apparatus and the arm 14 is in a closed state.

  FIG. 7 shows a side view of the process cartridge placed on the installation surface.

In the state of FIG. 7 in which the arm 14 is closed, the longitudinal regulating portion 10f2a and the receiving portion 14c overlap at the position X in the figure as seen from the longitudinal direction.
FIG. 8 shows a state where a force F1 is applied in the direction opposite to the toner seal pulling direction so that the process cartridge does not move when the user grasps the seal handle 10f4 and pulls out the toner seal 10f3.

  The arm 14 supporting the process cartridge receives the frictional force F2 from the installed surface. The direction of the frictional force F <b> 2 is the toner seal drawing direction, and is the rotation axis direction of the arm 14.

  A moment is applied to the support shaft 15 of the arm 14 by the frictional force F2. Even if this force is large, the unillustrated longitudinal regulating portion 10f2a and the receiving portion 14c can receive the force. Accordingly, no great force is applied to the support shaft 15.

  Further, a case where the process cartridge is tilted when the toner seal 10f3 is opened will be described.

  FIG. 9 shows a state where the process cartridge is tilted by the force F3 applied by the user.

  Even when the attitude of the process cartridge is forcibly changed, the third contact portion P3 provided on the toner frame 10f2 contacts the installation surface, and the attitude is not further inclined.

  Depending on the direction of the force applied by the user, the link member may open or remain closed. For example, when a force is applied in the direction of arrow F4 from the state of FIG. 9, the arm 14 receives a rotational force due to the frictional force F5 received from the first contact portion P1. At this time, the second contact portion P <b> 2 having a large radius from the rotation center acts as a rotation stopper for the arm 14.

  The case where there is no 2nd contact part P2 and the case where it exists are demonstrated using FIG.10 and FIG.1.

  Here, in order to clarify and explain the second contact portion P2, a diagram in which the second contact portion P2 is deformed into a convex shape is used. The same effect can be obtained even when the first contact portion P1 and the second contact portion P2 are continuously formed.

  When there is no contact portion, there are a case where the arm 14 is rotated by a frictional force (FIG. 10) and a case where the arm 14 does not rotate and slides on the installation surface (not shown).

  When rotated, the drum protection member 12 connected to the arm 14 opens and the photosensitive drum 7 is exposed.

  On the other hand, when the second contact portion P2 shown in FIG. 1 is provided, the second contact portion P2 having a larger radius of rotation than the first contact portion P1 is formed on the installation surface when rotated to a certain angle θ. In the event of collision, the rotation of the arm 14 is prevented from opening more than a certain angle θ. That is, the drum protection member 12 does not open more than a certain angle.

  Further, the longitudinal restriction portion 10f2a and the receiving portion 14c are arranged so as to overlap each other when viewed from the longitudinal direction in a range from the closed state of the link member to a certain angle θ. Accordingly, the longitudinal regulating portion 10f2a and the receiving portion 14c can receive the external force applied to the arm 14 regardless of whether the process cartridge is in a self-supporting posture or a posture in which the process cartridge is forcedly rotated.

  The longitudinal force receiving portion 14f2a and the receiving portion 14c reliably receive the external force received by the arm 14 in the operation of pulling out the toner seal, and no large force is applied to the rotation center of the arm 14.

  Here, the description of the second contact portion P is made in a convex shape, but it is not necessary to provide a convex shape. An effect can be obtained by making the radius of rotation larger at R2 of the second contact portion than R1 of the first contact portion.

  The process cartridge shown in the above-described embodiment is exemplified as a case where a single color image is formed. However, the process cartridge according to the present invention is provided with a plurality of developing means, and a plurality of color images (for example, two color images, three color images, or Can be suitably applied to a cartridge that forms a full color or the like.

The electrophotographic photosensitive member is not limited to the photosensitive drum, and includes, for example, the following. First, a photoconductor is used as the photoreceptor, and examples of the photoconductor include amorphous silicon, amorphous selenium, zinc oxide, titanium oxide, and organic photoconductor (OPC).
The process cartridge described above refers to a cartridge in which at least the developing means and the electrophotographic photosensitive member are integrated into a cartridge so as to be detachable from the main body of the image forming apparatus. The process cartridge can be attached to and detached from the apparatus main body by the user. Therefore, the maintenance of the apparatus main body can be performed by the user himself.

  Furthermore, in the above-described embodiment, the laser beam printer is exemplified as the electrophotographic image forming apparatus. However, the present invention is not limited to this. For example, an electrophotographic printer such as an electrophotographic copying machine and an LED printer, a facsimile machine, and the like. Naturally, it can also be used in an electrophotographic image forming apparatus such as a device, a word processor, or a multifunction machine (multifunction printer, etc.).

It is a side view of a process cartridge including a link member according to an embodiment of the present invention. 1 is a schematic cross-sectional view of an electrophotographic image forming apparatus according to an embodiment of the present invention. It is typical sectional drawing of the process cartridge which concerns on embodiment of this invention. It is an assembly drawing used for description of a developing device. It is an assembly drawing used for description of a drum protection member. It is a perspective view used for description of a link member. It is a side view of the process cartridge of an Example. It is a perspective view which opens the toner seal of an Example. FIG. 4 is a side view of the process cartridge according to the embodiment in which the posture is changed. It is a side view of the process cartridge deform | transformed in order to compare with an Example.

Explanation of symbols

A image forming apparatus main body B process cartridge P1 first contact portion P2 second contact portion P3 third contact portion 1 optical system 2 recording medium 3 transport means 3a cassette 3b pickup roller 3c pressure contact member 3d discharge roller 3f1, 3f2 transport Guide 4 Transfer roller 5 Fixing means 5a Driving roller 5b Heater 5c Support 5d Fixing rotator 6 Discharge unit 7 Photosensitive drum 8 Charging roller 9b Exposure opening 10 Developing unit 10a Toner chamber 10b Toner feeding member 10d Developing roller 10e Developing blade 10f1 Developing Frame body 10f2 toner frame body 10f2a length regulating portion 10f3 toner seal 10g end member 10h end member 10ha developing opening 10i developing chamber 10m spacer 11 drum unit 11a cleaning blade 11b squeeze sheet 11c With toner accommodating portion 11d drum frame 12 drum protecting member 13 wire 14 arm (link member)
14a Bearing portion 14c Receiving portion 15 Support shaft 16 Wire mounting portion

Claims (1)

A process that is detachable from the electrophotographic image forming apparatus, wherein the developing device is rotatably held by the developing device and the link member supports the weight of the process cartridge while the process cartridge is self-supporting on the installation surface. In the cartridge,
The link member is
First and second contact portions for supporting the process cartridge in a first posture in which the process cartridge is self-supporting on an installation surface;
Here, the second contact portion has a larger radius of rotation than the first contact portion, and has a longitudinal restriction receiving portion on a part of the outer side in the longitudinal direction,
The developing device includes:
A third contact portion that is a rotation regulating portion of the process cartridge with respect to the installation surface in a second posture in which the upper surface of the developing device is pressed vertically downward and the developing device approaches the installation surface;
A link member longitudinal restriction portion,
The link member longitudinal restriction portion is
The toner supply part to the developing means is detachably sealed so that the toner seal member is in front of the receiving part when viewed from the drawing direction, and in the range from the first attitude to the second attitude, A process cartridge, wherein the link member longitudinal restriction portion overlaps when viewed from the drawing direction.

Images