US Patent No. 9,389,584


Patent No. 9,389,584
Issue Date July 12, 2016
Title Electrophotographic Image Forming Apparatus, Process Cartridge And Developing Cartridge
Inventorship Wataru Uchida, Yokohama (JP)
Takeshi Niimura, Yokohama (JP)

Claim of US Patent No. 9,389,584

1. An image forming apparatus comprising:
a main assembly;
a supporting member capable of supporting a plurality of developing rollers and a plurality of photosensitive drums, said
supporting member being movable substantially linearly between an inside position which is inside said main assembly and an
outside position which is outside said main assembly, in a direction substantially perpendicular to axes of said developing
rollers while supporting said developing rollers and said photosensitive drums;

a plurality of developing cartridges each having the developing roller and a pair of side walls opposing each other in a longitudinal
direction of said developing roller, said developing cartridges being mountable to and dismountable from said supporting member,
wherein in a state that said supporting member supports the plurality of photosensitive drums in the outside position, said
developing cartridges are mountable to and dismountable from said supporting member, without removing said photosensitive

an urging member for urging said developing cartridge to urge said developing roller toward said photosensitive drum; and
a spacing member for spacing said developing roller and said photosensitive drum from each other,
wherein said developing cartridges each include an upper surface facing upward when mounted to said supporting member and
a projection projecting upwardly from the upper surface and having a shape providing a space through a middle portion thereof,

wherein with respect to the longitudinal direction of said developing roller, a width of said projection is narrower than
a distance between said pair of side walls,

wherein each said developing cartridge includes a cylindrical engaging portion extending in the longitudinal direction of
said developing roller to engage with said supporting member, wherein said cylindrical engaging portion protrudes from one
side wall of said pair of side walls, and wherein said engaging portion is movably engaged with said supporting member to
permit said developing cartridge to be moved relative to said photosensitive drum by said spacing member and said urging member.