Abstract: An image forming apparatus includes a driven unit and a drive transmitter. The drive transmitter includes a drive source, a drive gear, and a driven gear. The drive source is configured to drive the driven unit. The drive gear is configured to receive a driving force from the drive source. The driven gear is meshed with the drive gear. The drive transmitter is configured to transmit the driving force from the drive source to the driven unit. The drive gear or the driven gear is a crowned gear crowning-processed and the crowned gear has a crowning amount less than 50 ?m.

Abstract: An image forming apparatus includes a driven unit and a drive transmitter. The drive transmitter includes a drive source, a drive gear, and a driven gear. The drive source is configured to drive the driven unit. The drive gear is configured to receive a driving force from the drive source. The driven gear is meshed with the drive gear. The drive transmitter is configured to transmit the driving force from the drive source to the driven unit. The drive gear or the driven gear is a crowned gear crowning-processed and the crowned gear has a crowning amount less than 50 ?m.

Abstract: A planetary gear mechanism includes a plurality of planetary gears, an outer gear, a sun gear, a carrier, and a stick mount. The outer gear meshes with the plurality of planetary gears. The sun gear is coaxially disposed on the same axis as the outer gear and transmits force to the planetary gears. The carrier rotatably supports the plurality of planetary gears and is rotatably and floatingly supported. The carrier includes a hole through which a stick member penetrates in a direction of axis of rotation of the carrier. The stick member penetrates through the hole and is mounted on the stick mount. The stick mount is disposed opposite the carrier. The outer gear and the sun gear are held such that one of the outer gear and the sun gear does not rotate.

Abstract: A cleaning device, which is included in a process cartridge and an image forming apparatus, includes a cleaning blade configured to remove a material attached to a surface of an image bearer, a cleaning case configured to contain the material removed by the cleaning blade, and a removed material receiver configured to receive the material failed to enter into the cleaning case when the material is removed by the cleaning blade, the removed material receiver having a first range at both ends in a width direction of the cleaning blade and a second range at a center in the width direction of the cleaning blade. A volume per unit length in a width direction of the first range is greater than a volume per unit length in a width direction of the second range.

Abstract: A cleaning device includes a cleaning blade disposed in contact with a rotator, a toner collecting section disposed along the rotator and the cleaning blade and includes a groove extending in an axial direction of the rotator, a conveyor disposed in the groove, and an agitator disposed on a side of a rim of the groove. The conveyor rotates to convey the toner in a longitudinal direction of the groove. The agitator vibrates through contact with the conveyor and includes comb-tooth portions lined in a comb shape in the longitudinal direction of the groove, and bent portions, each of which is bent from an end of one of the comb-tooth portions. The comb-tooth portions contact a circumference of the conveyor to vibrate. The bent portions are lined at intervals smaller than intervals on a base side of the comb-tooth portions.

Abstract: A toner conveyance device includes a downward passage, a reciprocating member disposed in the downward passage, to move in a vertical direction in which the downward passage extends, a conveyance passage communicating with a lower end of the downward passage and extending in a direction crossing the vertical direction, a conveyor to rotate in the conveyance passage around an axis extending along the conveyance passage to transport the toner, and a flexible member projecting from a bottom of the reciprocating member toward the conveyance passage. The flexible member extends in the axial direction of the conveyor and moves together with the reciprocating member. When the reciprocating member is at a lowest position, a lower end of the flexible member opposes a portion of the conveyor downstream from an upper end thereof in a rotation direction thereof.

Abstract: A device disposed opposing an image bearer includes a roller to rotate while contacting a surface of the image bearer, a rolling bearing fitted around a shaft located at an end of the roller in an axial direction of the roller, a frame to house the roller, and a bearing support removably attached to the frame. The rolling bearing includes an outer ring, an inner ring, and a rolling element disposed between the outer ring and the inner ring. The bearing support holds, from an outer-ring side, the rolling bearing interposed between the bearing support and the frame. The bearing support includes a receiving portion to contact the outer ring of the rolling bearing and bias the rolling bearing toward the frame in a direction in which the rolling bearing is interposed between the bearing support and the frame.

Abstract: A cleaning device, which is included in a process cartridge and an image forming apparatus, includes a cleaning blade configured to remove a material attached to a surface of an image bearer, a cleaning case configured to contain the material removed by the cleaning blade, and a removed material receiver configured to receive the material failed to enter into the cleaning case when the material is removed by the cleaning blade, the removed material receiver having a first range at both ends in a width direction of the cleaning blade and a second range at a center in the width direction of the cleaning blade. A volume per unit length in a width direction of the first range is greater than a volume per unit length in a width direction of the second range.

Abstract: An image forming apparatus includes an image bearer to bear a toner image, a lubricant supply roller to supply lubricant to a surface of the image bearer, a rotation speed changer to change a rotation speed of the lubricant supply roller, and a controller to control the rotation speed changer to change the rotation speed of the lubricant supply roller to a target speed based on a predetermined condition. The controller is configured to control the rotation speed changer to avoid a predetermined speed range.

Abstract: A cleaning device includes a cleaning blade disposed in contact with a rotator, a toner collecting section disposed along the rotator and the cleaning blade and includes a groove extending in an axial direction of the rotator, a conveyor disposed in the groove, and an agitator disposed on a side of a rim of the groove. The conveyor rotates to convey the toner in a longitudinal direction of the groove. The agitator vibrates through contact with the conveyor and includes comb-tooth portions lined in a comb shape in the longitudinal direction of the groove, and bent portions, each of which is bent from an end of one of the comb-tooth portions. The comb-tooth portions contact a circumference of the conveyor to vibrate. The bent portions are lined at intervals smaller than intervals on a base side of the comb-tooth portions.

Abstract: A toner conveyance device includes a downward passage, a reciprocating member disposed in the downward passage, to move in a vertical direction in which the downward passage extends, a conveyance passage communicating with a lower end of the downward passage and extending in a direction crossing the vertical direction, a conveyor to rotate in the conveyance passage around an axis extending along the conveyance passage to transport the toner, and a flexible member projecting from a bottom of the reciprocating member toward the conveyance passage. The flexible member extends in the axial direction of the conveyor and moves together with the reciprocating member. When the reciprocating member is at a lowest position, a lower end of the flexible member opposes a portion of the conveyor downstream from an upper end thereof in a rotation direction thereof.

Abstract: An image forming apparatus includes a process cartridge that includes an image bearer including a rotary shaft and rotates about the rotary shaft; a charger to charge a surface of the image bearer; and a developing device to develop an electrostatic latent image formed on the image bearer into a visible toner image. The charger includes a charging roller that rotates about a shaft together with the image bearer during image formation and electrically charges a surface of the image bearer. A surface linear speed of the charging roller is made slower than a surface linear speed of the image bearer. The image forming apparatus includes a charging roller controller that switches the rotational speed of the charging roller to a first rotational speed slower than the linear speed of the image bearer and a second rotational speed identical to the linear speed of the image bearer.

Abstract: A device disposed opposing an image bearer includes a roller to rotate while contacting a surface of the image bearer, a rolling bearing fitted around a shaft located at an end of the roller in an axial direction of the roller, a frame to house the roller, and a bearing support removably attached to the frame. The rolling bearing includes an outer ring, an inner ring, and a rolling element disposed between the outer ring and the inner ring. The bearing support holds, from an outer-ring side, the rolling bearing interposed between the bearing support and the frame. The bearing support includes a receiving portion to contact the outer ring of the rolling bearing and bias the rolling bearing toward the frame in a direction in which the rolling bearing is interposed between the bearing support and the frame.

Abstract: An image forming apparatus includes an image bearer to bear a toner image, a lubricant supply roller to supply lubricant to a surface of the image bearer, a rotation speed changer to change a rotation speed of the lubricant supply roller, and a controller to control the rotation speed changer to change the rotation speed of the lubricant supply roller to a target speed based on a predetermined condition. The controller is configured to control the rotation speed changer to avoid a predetermined speed range.

Abstract: A planetary gear mechanism includes a plurality of planetary gears, an outer gear, a sun gear, a carrier, and a stick mount. The outer gear meshes with the plurality of planetary gears. The sun gear is coaxially disposed on the same axis as the outer gear and transmits force to the planetary gears. The carrier rotatably supports the plurality of planetary gears and is rotatably and floatingly supported. The carrier includes a hole through which a stick member penetrates in a direction of axis of rotation of the carrier. The stick member penetrates through the hole and is mounted on the stick mount. The stick mount is disposed opposite the carrier. The outer gear and the sun gear are held such that one of the outer gear and the sun gear does not rotate.

Abstract: An image forming apparatus includes a process cartridge that includes an image bearer including a rotary shaft and rotates about the rotary shaft; a charger to charge a surface of the image bearer; and a developing device to develop an electrostatic latent image formed on the image bearer into a visible toner image. The charger includes a charging roller that rotates about a shaft together with the image bearer during image formation and electrically charges a surface of the image bearer. A surface linear speed of the charging roller is made slower than a surface linear speed of the image bearer. The image forming apparatus includes a charging roller controller that switches the rotational speed of the charging roller to a first rotational speed slower than the linear speed of the image bearer and a second rotational speed identical to the linear speed of the image bearer.

Abstract: A lubricant supplying device includes a lubricant supplier contacting an image bearer, a solid lubricant contacting the roller, a detector detecting a lubricant amount, and a controller controlling a supplying of the roller based on a detector detection. The detector outputs to the controller a first signal of a near-end state when the amount reaches a first amount, a second signal of an end state when the amount reaches a second amount smaller than the first amount, and a third signal of an absolute end state when the amount reaches a third amount smaller than the second amount. The controller temporarily stops the supplying when the second signal is output, cancels a roller temporary stopped state even when lubricant replacement is not completed after this state, stops the supplying when the third signal is output, and maintains a roller stopped state until the replacement is completed after this state.

Abstract: A lubricant supplying device includes a lubricant supplier contacting an image bearer, a solid lubricant contacting the roller, a detector detecting a lubricant amount, and a controller controlling a supplying of the roller based on a detector detection. The detector outputs to the controller a first signal of a near-end state when the amount reaches a first amount, a second signal of an end state when the amount reaches a second amount smaller than the first amount, and a third signal of an absolute end state when the amount reaches a third amount smaller than the second amount. The controller temporarily stops the supplying when the second signal is output, cancels a roller temporary stopped state even when lubricant replacement is not completed after this state, stops the supplying when the third signal is output, and maintains a roller stopped state until the replacement is completed after this state.

Abstract: A driving device includes a drive source, a planetary gear decelerator, a drive-target shaft, a rotation speed detector, and a sensor mount. The planetary gear decelerator includes a planetary gear mechanism equipped with an output shaft, a sun gear, an outer gear, a plurality of planetary gears, and a rotatable first carrier. The outer gear is made of resin and includes a deformable portion at a drive target side, and the deformable portion is elastically deformable in a radial direction. The plurality of planetary gears engages the sun gear and the outer gear. The rotatable first carrier rotatably supports the planetary gears. The rotation speed detector detects a rotation speed of the planetary gear decelerator, and includes a sensor and a detection target disposed coaxially on the output shaft. The sensor mount supports the sensor and moves in the radial direction in accordance with elastic deformation of the outer gear.

Abstract: A rotating-body driving device that includes a rotating body; a driving source; a reduction gear that includes an output shaft and a gear rotating at a non-integer ratio of rotation period to a rotation period of the output shaft, and the reduction gear reducing rotation speed of the driving source; a pulse-signal generating unit; a pulse-count storage unit; a speed-fluctuation storage unit that stores therein a rotation speed fluctuation of the output shaft; and a driving-source control unit. The driving-source control unit detects the speed fluctuation information associated with the accumulated number of pulse signals from the speed-fluctuation storage unit, and performs for the driving source a feedforward control to set off the rotation speed fluctuation.