What is claimed is:
1. A process cartridge detachably mountable to an image forming apparatus for forming an image on a recording material, comprising:
a first unit including at least an image-bearing member,
a second unit including at least a developing device for developing an electrostatic image formed on the image-bearing member, and
connection means, for separably connecting said first unit and said second unit with each other, which permits integral mounting and demounting of said first and second units relative to the image forming apparatus,
wherein said second unit has a life which substantially equals to a life of the image forming apparatus, and said first unit is replaceable by separation thereof from said second unit outside the image forming apparatus.
2. A cartridge according to claim 1, which is disposed detachably mountable to the image forming apparatus in a direction substantially perpendicular to a rotation axis of the image forming apparatus.
3. A cartridge according to claim 1, wherein said second unit is further provided with mounting means for detachably mounting a toner container for supplying a toner to the developing device.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A compact casing structure, integrally made by press-fitting at least one metallic material, the casing structure including a base portion which has a first stress region and a plurality of second stress regions, the plurality of second stress regions formed in circle shapes and arranged in intervals within the first stress region, wherein the density of the first stress region is lower than density of the second stress regions, so that a stress of the first stress region is higher than stresses of the second stress regions.
2. The compact casing structure according to claim 1, wherein the casing structure has a plurality of side walls at a peripheral of the base portion, and the base portion and the plurality of side walls form an accommodating space correspondingly.
3. The compact casing structure as defined in claim 2, wherein the base portion of the casing structure is provided with at least one concave portion corresponding to the accommodating space.
4. The compact casing structure as defined in claim 2, wherein the base portion of the casing structure is provided with at least one convex portion corresponding to the accommodating space.
5. The compact casing structure as defined in claim 2, wherein the base portion of the casing structure is provided with at least one connection portion corresponding to the accommodating space.
6. The compact casing structure according to claim 1, wherein an outer surface of the base portion of the casing structure is provided with knurling.
7. The compact casing structure according to claim 1, wherein an outer surface of the base portion of the casing structure is spray-coated with color or image.