Image forming apparatus

Patent metadata

Field	Value
Publication number	US-10754265-B2
Application number	US-201916679459-A
Country	US
Kind code	B2
Filing date	Nov 11, 2019
Priority date	Nov 14, 2018
Publication date	Aug 25, 2020
Grant date	Aug 25, 2020

Abstract

An image forming apparatus including: an image bearing member; a developing member to supply a developer to the image bearing member; and a cleaning member to clean a peripheral surface of the image bearing member in contact with the peripheral surface, wherein a plurality of grooves extend in a circumferential direction on the peripheral surface, and have a width in a generatrix direction of the peripheral surface within a range of at least 0.5 μm and not more than 40 μm, and are formed to be side by side in the generatrix direction; the number of the grooves is at least 20 and not more than 1000 per a width of 1000 μm in the generatrix direction of the peripheral surface; and an average depth (Rvk) of a valley of a projection under a core section of a roughness curve of the peripheral surface is 0.08 μm or less.

First claim

What is claimed is:

1. An image forming apparatus comprising:
a cylindrical image bearing member including a cylindrical support and an organic photosensitive layer provided on the cylindrical support;
a developing member configured to supply a developer to the image bearing member for developing a latent image formed on a peripheral surface of the image bearing member; and
a cleaning member configured to clean the peripheral surface in contact with the peripheral surface of the image bearing member,
wherein a plurality of grooves extend in a circumferential direction on the peripheral surface of the image bearing member, and have a width in a generatrix direction of the peripheral surface within a range of at least 0.5 μm and not more than 40 μm, and are formed to be side by side in the generatrix direction;
the number of the grooves is at least 20 and not more than 1000 per a width of 1000 μm in the generatrix direction of the peripheral surface of the image bearing member; and
an average depth (Rvk) of a valley of a projection under a core section of a roughness curve of the peripheral surface of the image bearing member is 0.08 μm or less.

2. The image forming apparatus according to claim 1 , wherein
an average height (Rpk) of a ridge of the projection above the core section of the roughness curve of the peripheral surface of the image bearing member is at least 0.01 μm and not more than 0.02 μm.

3. The image forming apparatus according to claim 2 , wherein
a sum of
the average height (Rpk) of the ridge of the projection above the core section of the roughness curve of the peripheral surface of the image bearing member,
a height (Rk) of a core portion forming a center of the roughness curve of the peripheral surface of the image bearing member, and
the average depth (Rvk) of the valley of the projection under the core section of the roughness curve of the peripheral surface of the image bearing member
is 0.24 μm or less.

4. The image forming apparatus according to claim 1 , wherein
in a cross section perpendicular to a rotation axis of the image bearing member,
an angle, between an opposite plane of the cleaning member and a tangent line passing through a virtual point on the peripheral surface of the image bearing member, is designated as a set angle θ,
the opposite plane is a place facing the peripheral surface of the image bearing member on a downstream side of an edge of the cleaning member in a rotation direction of the image bearing member when the cleaning member is disposed with respect to the image bearing member so that the edge of the cleaning member is in contact with the virtual point, and
a penetration amount of the cleaning member, when the cleaning member is moved so as to penetrate with respect to the image bearing member in a direction perpendicular to the tangent line from the virtual point, is denoted by δ, following conditions are satisfied,
18≤θ≤26(°), and

0.6≤δ≤1.4(mm).

5. The image forming apparatus according to claim 1 , wherein
a dynamic hardness DHs of a contact portion of the cleaning member in contact with the image bearing member satisfies the following condition:
0.07(mN/μm 2 )≤ DHs ≤1.1(mN/μm 2 ).

6. The image forming apparatus according to claim 1 , wherein
the developer includes a toner having a toner particle,
the toner particle has a surface layer including an organosilicon polymer having a structure represented by a following formula (1),
a fixing ratio of the organosilicon polymer on a surface of the toner particle is 90% or more, and
the toner has a Martens hardness of at least 200 MPa and not more than 1100 MPa when measured under a maximum load of 2.0×10 −4 N,
R—SiO 3/2   Formula (1)

 wherein R is a hydrocarbon group having at least 1 and not more than 6 carbon atoms.

7. The image forming apparatus according to claim 6 , wherein
a weight average particle diameter of the toner is at least 3.0 μm and not more than 10.0 μm.

8. The image forming apparatus according to claim 1 further comprising:
a frame which rotatably supports the image bearing member and to which the cleaning member is fixed,
wherein the cleaning member includes an elastic portion and a support portion that supports the elastic portion;
a first end of the elastic portion is fixed to the support portion, and a second end of the elastic portion, which is a free end, is in contact with the peripheral surface of the image bearing member;
a first end of the support portion is fixed to the frame, and the elastic portion is fixed to a second end of the support portion, which is a free end;
a direction extending from the first end of the support portion to the second end of the elastic portion is opposite to a rotation direction of the image bearing member at a portion where the second end of the support portion is in contact with the peripheral surface of the image bearing member.

9. The image forming apparatus according to claim 1 , wherein
in a posture when using, the image bearing member rotates so that the peripheral surface moves in a direction from an upper side toward a lower side at a portion where the cleaning member is in contact with the peripheral surface of the image bearing member.

Assignees

• Canon Kk

Inventors

• Yamauchi Hisashi
• Nakata Keitaro
• Ikami Yasukazu
• Ikada Kosuke
• Yamawaki Kentaro

Classifications

• G03G9/09328

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• G03G21/0011

  using a blade; Details of cleaning blades, e.g. blade shape, layer forming · CPC title

• G03G9/0819

  characterised by the dimensions of the particles · CPC title

• G03G15/751 Primary

  relating to drum (G03G15/757 takes precedence) · CPC title

• G03G9/08797

  characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature · CPC title