Abstract: A rotary development device includes a rotating member, a development unit which is detachably mounted on the rotating member, an engaging member which engages the rotating member and the development unit. The engaging member is provided so that a positioning pin is fitted into a positioning hole. The rotary development device further includes a biasing member which biases either the development unit or the rotating member so that the positioning pin is biased to inner face of the positioning hole.

Abstract: In an image forming apparatus including an image carrier formed with a latent image, a developing device having a developing roller driven by a stepping motor and carrying a developer for developing the latent image, a rotary development apparatus for supporting the developing device centering on a rotating shaft to rotate to move to a developing position opposed to the image carrier and constituted to form an image by developing the latent image formed at the image carrier by the developing device at the developing position and transferring the developed developer image to a medium at a transferring position, the developing roller disposed at the developing position is driven to rotate by the stepping motor in a region of the latent image of the image carrier and stopped to rotate in a region in which the latent image is not formed of the image carrier to hold in the same phase by a current lower than a current in driving to rotate the developing roller to constitute a holding state.

Abstract: An image forming apparatus includes: an image bearing body for bearing a latent image; a plurality of attach/detach sections to each of which a developer container for containing developer used for developing the latent image can be attached; and a container attachment mechanism for allowing a developer container containing developer of a certain color to be attached to any of the plurality of attach/detach sections, and a developer container containing developer of a color other than the certain color to be attached only to a predetermined attach/detach section of among the plurality of attach/detach sections.

Abstract: An image forming apparatus where during the image forming operation, the completion of development by one of development cartridges is followed by the rotation of a rotary for setting the next development cartridge to a development position. The rotational speed v of the rotary is increased linearly to the maximum speed vmax and, after that, is decreased linearly to stop the rotary when the next development cartridge reaches the development position. During replacement of the development cartridge, the rotary is rotated to set the development cartridge to be replaced to the replacement position. The rotational speed of the rotary is set to be a constant speed v1 in a region other than a contact region where an input gear of the development side is in contact with a driving gear of the fixed side and a speed lower than the speed v1 in the contact region (the minimum speed v2).

Abstract: A rotary developing device having a cylindrical rotary developing unit, and a plurality of development members mounted around the periphery of the rotary developing unit. The rotary developing unit is driven to bring one of the development members to the developing position facing a photoreceptor and subsequently the transmission of the driving power to the development member is conducted. In the rotary developing device, the driving direction of the development members at a driving power transmitting section is set to be the same as the driving direction of the rotary developing unit and a simple additional structure employing an electromagnetic clutch or a one-way clutch is applied to the driving power transmitting section, thereby avoiding a collision of tooth tops between gears, damping the impact generated by a collision, and reducing vibration and damage of tooth tops. Therefore, the production of image defects due to registration error are prevented.

Abstract: A rotary developing apparatus having a plurality of developing devices mounted along the outer periphery of a cylindrical rotary unit. A first gear train for connecting the rotary unit to a drive source to rotate the rotary unit. A second gear train for connecting a developing roller of a developing device revolved and stopped at a developing position, as a result of the rotary unit being rotationally driven, to the drive source to rotate the developing roller. The rotary unit and the developing roller are rotated with the same motor used as the drive source by switching between the connections of the gear trains, thereby rapidly damping vibration generated by the rotation of the rotary unit and vibration generated by the rotation of the developing roller, and thus eliminating image defects due to displacement, etc.

Abstract: A rotary developing device having a cylindrical rotary developing unit, and a plurality of development members mounted around the periphery of the rotary developing unit. The rotary developing unit is driven to bring one of the development members to the developing position facing a photoreceptor and subsequently the transmission of the driving power to the development member is conducted. In the rotary developing device, the driving direction of the development members at a driving power transmitting section is set to be the same as the driving direction of the rotary developing unit and a simple additional structure employing an electromagnetic clutch or a one-way clutch is applied to the driving power transmitting section, thereby avoiding a collision of tooth tops between gears, damping the impact generated by a collision, and reducing vibration and damage of tooth tops. Therefore, the production of image defects due to registration error are prevented.

Abstract: A rotary development device includes a rotating member, a development unit which is detachably mounted on the rotating member, an engaging member which engages the rotating member and the development unit. The engaging member is provided so that a positioning pin is fitted into a positioning hole. The rotary development device further includes a biasing member which biases either the development unit or the rotating member so that the positioning pin is biased to inner face of the positioning hole.

Abstract: A rotary developing device having a cylindrical rotary developing unit, and a plurality of development members mounted around the periphery of the rotary developing unit. The rotary developing unit is driven to bring one of the development members to the developing position facing a photoreceptor and subsequently the transmission of the driving power to the development member is conducted. In the rotary developing device, the driving direction of the development members at a driving power transmitting section is set to be the same as the driving direction of the rotary developing unit and a simple additional structure employing an electromagnetic clutch or a one-way clutch is applied to the driving power transmitting section, thereby avoiding a collision of tooth tops between gears, damping the impact generated by a collision, and reducing vibration and damage of tooth tops. Therefore, the production of image defects due to registration error are prevented.

Abstract: A rotary developing apparatus having a plurality of developing devices mounted along the outer periphery of a cylindrical rotary unit 2 includes a first gear train 81, 6 and 21 for connecting the rotary unit to a drive source 8 to rotate the rotary unit 2, a second gear train 81, 7, 5 and 4 for connecting a developing roller 3 of a developing device revolved and stopped at a developing position, as a result of the rotary unit 2 being rotationally driven, to the drive source 8 to rotate the developing roller 3, and a drive switching means 9 for switching between the first gear train and the second gear train to connect either of them to the drive source 8.

Abstract: A rotary developing apparatus having a plurality of developing devices mounted along the outer periphery of a cylindrical rotary unit. A first gear train for connecting the rotary unit to a drive source to rotate the rotary unit. A second gear train for connecting a developing roller of a developing device revolved and stopped at a developing position, as a result of the rotary unit being rotationally driven, to the drive source to rotate the developing roller. The rotary unit and the developing roller are rotated with the same motor used as the drive source by switching between the connections of the gear trains, thereby rapidly damping vibration generated by the rotation of the rotary unit and vibration generated by the rotation of the developing roller, and thus eliminating image defects due to displacement, etc.

Abstract: In an image forming apparatus of the present invention, during the image forming operation, the completion of development by one of development cartridges is followed by the rotation of a rotary for setting the next development cartridge to a development position. The rotational speed v of the rotary for this is increased linearly to the maximum speed vmax and, after that, is decreased linearly to stop the rotary when the next development cartridge reaches the development position. During the replacement of the development cartridge in the non-image forming operation, the rotary is rotated to set the development cartridge to be replaced to the replacement position. The rotational speed of the rotary for this is set to be a constant speed v1 in a region other than a contact region where an input gear of the development side is in contact with a driving gear of the fixed side and a speed lower than the speed v1 in the contact region (the minimum speed v2).

Abstract: A rotary developing device comprises: a cylindrical rotary developing unit 1, a plurality of development members 3 mounted around the periphery of said rotary developing unit, and driving means 13, 15, wherein the rotary developing unit is driven by the driving means to bring one of the development members 3 to the developing position facing a photoreceptor 10 and subsequently the transmission of the driving power to the development member 3 is conducted. In the rotary developing device, the driving direction of the development members at a driving power transmitting section is set to be the same as the driving direction of the rotary developing unit and a simple additional structure employing an electromagnetic clutch or a one-way clutch 11 is applied to the driving power transmitting section, thereby avoiding a collision of tooth tops between gears, damping the impact generated by a collision, and reducing vibration and damage of tooth tops.

Abstract: A rotary developing apparatus having a plurality of developing devices mounted along the outer periphery of a cylindrical rotary unit 2 includes a first gear train 81, 6 and 21 for connecting the rotary unit to a drive source 8 to rotate the rotary unit 2, a second gear train 81, 7, 5 and 4 for connecting a developing roller 3 of a developing device revolved and stopped at a developing position, as a result of the rotary unit 2 being rotationally driven, to the drive source 8 to rotate the developing roller 3, and a drive switching means 9 for switching between the first gear train and the second gear train to connect either of them to the drive source 8.

Abstract: An opening for discharging toner is formed in a lower part of a cartridge body containing toner. A shutter mounting body is mounted on the opening. A first shutter is slidably mounted on the shutter mounting body. A second shutter is slidably mounted on the first shutter. A front end of a sealing member for sealing the opening is extended, the extended front end being inserted through a seal traction opening formed in a front end of the second shutter, and fixed to a front end of the first shutter. When the second shutter is pulled out of the shutter mounting body, the sealing member is towed by the seal traction opening. In addition, the first shutter is further towed by the sealing member, to be also pulled out. Consequently, nearly half of the sealing member from its front end is stripped.

Abstract: It is a major object of the present invention to break down and level a heap-up of toner built in the hopper through dropping from the cartridge when feeding toner into the hopper and to prevent toner from leakage from the cartridge due to erroneous operation with a remarkably simple and cheap construction. Namely, the leveling member moves a plurality of number of times in line with engaging and disengaging operation of the cartridge for the hopper and opening and closing operation of the cartridge in the same direction of the shutter, thereby causing a heap-up of toner built in the hopper housing of the hopper to be effectively broken down and leveled. Furthermore, only when the shutter is in its closed status for the cartridge, the cartridge can be removed from the opening of the hopper.

Abstract: An opening for discharging toner is formed in a lower part of a cartridge body containing toner. A shutter mounting body is mounted on the opening. A first shutter is slidably mounted on the shutter mounting body. A second shutter is slidably mounted on the first shutter. A front end of a sealing member for sealing the opening is extended, the extended front end being inserted through a seal traction opening formed in a front end of the second shutter, and fixed to a front end of the first shutter. When the second shutter is pulled out of the shutter mounting body, the sealing member is towed by the seal traction opening. In addition, the first shutter is further towed by the sealing member, to be also pulled out. Consequently, nearly half of the sealing member from its front end is stripped.