Abstract: A cleaning apparatus includes a blade to remove one or more toner particles remaining on a photosensitive body of an electrophotographic type image forming apparatus. The toner particles have a mean particle diameter D and a standard deviation ? of a particle size distribution. The blade is arranged on the photosensitive body to satisfy a following condition. ? ? sin ? ? ? 1 + cos ? ? ? , When an imaginary sphere having a diameter of (D??) contacts the photosensitive body and the blade, ? is an angle defined by a tangent line at a contact point between the sphere and the photosensitive body and a tangent line at a contact point between the sphere and the blade, sandwiching the sphere therebetween. ? is a smaller friction coefficient of a friction coefficient between the toner particle and the photosensitive body and a friction coefficient between the toner particle and the blade.

Abstract: A cleaning apparatus includes a blade to remove one or more toner particles remaining on a photosensitive body of an electrophotographic type image forming apparatus. The toner particles have a mean particle diameter D and a standard deviation ? of a particle size distribution. The blade is arranged on the photosensitive body to satisfy a following condition. ? ? sin ? ? ? 1 + cos ? ? ? , When an imaginary sphere having a diameter of (D??) contacts the photosensitive body and the blade, ? is an angle defined by a tangent line at a contact point between the sphere and the photosensitive body and a tangent line at a contact point between the sphere and the blade, sandwiching the sphere therebetween. ? is a smaller friction coefficient of a friction coefficient between the toner particle and the photosensitive body and a friction coefficient between the toner particle and the blade.

Abstract: A transfer member transporting section is disposed so as to bring a tip end of a transfer member into contact with a peripheral face of a transfer rotary member before the tip end of the transfer member enters a nip area. A bias power supply has a polarity inverting function of, during a period from a timing when the tip end of the transfer member is brought into contact with the transfer rotary member by the transfer member transporting section, to that when the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is identical with that of a toner, to the transfer rotary member, and after the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is opposite to that of the toner, to the transfer rotary member.

Abstract: A developing unit in an electro-photographic apparatus such as a printer, a facsimile and a copier for actualizing an image employing colored particles such as toner, and more particularly to a developing unit for forming a toner image on the surface of a photosensitive body. The developing unit includes a plurality of developing rollers each having a core and a sleeve. The sleeve accommodates the core. The plurality of developing rollers include a first developing roller and a second developing roller. The sleeve for the first developing roller is rotated to move in the same direction as a moving direction of the surface of the photosensitive body. The sleeve for the second developing roller is rotated to move in an opposite direction to the moving direction of the surface of the photosensitive body. The core of only one of the plurality of developing rollers is driven in rotation while the other core is fixed.

Abstract: A transfer member transporting section is disposed so as to bring a tip end of a transfer member into contact with a peripheral face of a transfer rotary member before the tip end of the transfer member enters a nip area. A bias power supply has a polarity inverting function of, during a period from a timing when the tip end of the transfer member is brought into contact with the transfer rotary member by the transfer member transporting section, to that when the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is identical with that of a toner, to the transfer rotary member, and after the tip end of the transfer member enters the nip area, applying a voltage of a polarity which is opposite to that of the toner, to the transfer rotary member.

Abstract: A developing unit in an electro-photographic apparatus such as a printer, a facsimile and a copier for actualizing an image employing colored particles such as toner, and more particularly to a developing unit for forming a toner image on the surface of a photosensitive body. The developing unit includes a plurality of developing rollers each having a core and a sleeve. The sleeve accommodates the core. The plurality of developing rollers include a first developing roller and a second developing roller. The sleeve for the first developing roller is rotated to move in the same direction as a moving direction of the surface of the photosensitive body. The sleeve for the second developing roller is rotated to move in an opposite direction to the moving direction of the surface of the photosensitive body. The core for at least one of the plurality of developing rollers is driven in rotation.