Abstract: A development device includes a development container, a stirring conveyance member, a developer carrier, a vent hole, a filter, and a developer leakage prevention sheet. The stirring conveyance member conveys, while stirring, the developer containing toner inside the development container. The developer carrier carries on its outer circumferential surface the developer to feed the toner to an image carrier on which an electrostatic latent image is formed. The vent hole is formed in the development container to allow the inside and outside of the development container to communicate with each other. The filter is arranged to cover the vent hole from outside the development container. The developer leakage prevention sheet is flexible and is arranged inside the development container, opposite the vent hole so as to overlap the entire vent hole. A gap is formed between the developer leakage prevention sheet and the opening edge of the vent hole.

Abstract: A developing device (3a-3d) includes a development container (20); a stirring-conveying member (25); a toner detection sensor (51), and a scraper (52) that cleans a detection surface (51a) of the toner detection sensor (51). The scraper (52) includes a first member (52a) that contacts the detection surface (51a) of the toner detection sensor (51) during forward rotation of the stirring-conveying member (25), and a second member (52b) that contacts the detection surface (51a) of the toner detection sensor (51) during reverse rotation of the stirring-conveying member (25). The stirring-conveying member (25) includes a scraper holder (60) that holds the scraper (52) along inclination of a conveying blade (25b). The scraper holder (60) includes a first holding portion (61) that holds one side-end of the scraper (52) and a second holding portion (62) that holds another side-end of the scraper (52).

Abstract: A developing device (3a-3d) includes a development container (20); a stirring-conveying member (25); a toner detection sensor (51), and a scraper (52) that cleans a detection surface (51a) of the toner detection sensor (51). The scraper (52) includes a first member (52a) that contacts the detection surface (51a) of the toner detection sensor (51) during forward rotation of the stirring-conveying member (25), and a second member (52b) that contacts the detection surface (51a) of the toner detection sensor (51) during reverse rotation of the stirring-conveying member (25). The stirring-conveying member (25) includes a scraper holder (60) that holds the scraper (52) along inclination of a conveying blade (25b). The scraper holder (60) includes a first holding portion (61) that holds one side-end of the scraper (52) and a second holding portion (62) that holds another side-end of the scraper (52).

Abstract: In a toner supply device (40), a horizontal transport portion (42) is connected to a vertical transport portion (41). A stirring transport screw (25) includes a rotary shaft (25a) and a supply blade (25c), and transports toner in the horizontal transport portion (42) toward the rotary shaft (25a). A drive input gear (50) inputs a rotational drive force to the rotary shaft (25a). A crank shaft (47) has a central shaft (47a) connected to the drive input gear (50) and is rotated at a lower speed than the rotary shaft (25a), and an eccentric shaft (47c) extending in parallel to the central shaft (47a) from a position radially outward from the central shaft. One end of the toner loosening member (45) is connected to the eccentric shaft (47c), and the toner loosening member (45) is reciprocatingly moved in the vertical direction in the vertical transport portion (41) due to a circumferential movement operation of the eccentric shaft (47c) centered on the central shaft (47a).

Abstract: A driving force transmission device includes a clutch, an output shaft, a bearing and an annular shim. The clutch is capable of being switched between a transmission of a rotational force and an interruption of the transmission of the rotational force. The output shaft outputs the rotational force of the clutch. The bearing supports an end portion of the output shaft with grease. The annular shim is disposed around the end portion of the output shaft between the clutch and the bearing. The shim has a through hole through which the end portion of the output shaft is inserted. The through hole has the same shape as a cross section of the end portion of the output shaft. A circumferential edge of the through hole comes into tightly contact with an outer circumferential face of the end portion of the output shaft.

Abstract: The charging device includes a charging roller, a bush and a case. The charging roller is configured to come into contact with or be close to a surface of an image carrier and configured to charge the surface of the image carrier. The bush is configured to support an end portion of the charging roller in a rotatable manner. To the case, the end portion of the charging roller is attached along a predetermined attachment direction by the bush. The case includes a pair of guide walls standing along the attachment direction so as to guide the bush. The bush includes a bearing part and a restriction part. The end portion of the charging roller is inserted into the bearing part. The pair of guide walls is put between the bearing part and the restriction part.

Abstract: The charging device includes a charging roller, a bush and a case. The charging roller is configured to come into contact with or be close to a surface of an image carrier and configured to charge the surface of the image carrier. The bush is configured to support an end portion of the charging roller in a rotatable manner. To the case, the end portion of the charging roller is attached along a predetermined attachment direction by the bush. The case includes a pair of guide walls standing along the attachment direction so as to guide the bush. The bush includes a bearing part and a restriction part. The end portion of the charging roller is inserted into the bearing part. The pair of guide walls is put between the bearing part and the restriction part.

Abstract: An image forming apparatus includes an image carrier, a removal roller, a collection roller, a housing, a screw, and a seal. The removal roller rotates while in contact with the intermediate transfer belt and removes residual toner from the intermediate transfer belt. The collection roller rotates while in contact with the removal roller so as to collect, from the removal roller by electrostatic force, waste toner that is the residual toner removed by the removal roller. The housing has an upper opening for receiving the waste toner collected by the collection roller and stores the waste toner. The screw conveys the waste toner stored in the housing. The seal comes into contact with the collection roller and closes a gap between the collection roller and the housing at the upper opening.

Abstract: An image forming apparatus includes an image carrier, a removal roller, a collection roller, a housing, a screw, and a seal. The removal roller rotates while in contact with the intermediate transfer belt and removes residual toner from the intermediate transfer belt. The collection roller rotates while in contact with the removal roller so as to collect, from the removal roller by electrostatic force, waste toner that is the residual toner removed by the removal roller. The housing has an upper opening for receiving the waste toner collected by the collection roller and stores the waste toner. The screw conveys the waste toner stored in the housing. The seal comes into contact with the collection roller and closes a gap between the collection roller and the housing at the upper opening.

Abstract: A charging device (51) includes a charging roller (65), a supporting section (71), a guide (73), a first biasing section (75), and a second biasing section (90). The charging roller (65) charges an image bearing member (50). The supporting section (71) supports the charging roller (65) such that the charging roller (65) is rotatable. The guide (73) guides the supporting section (71) in a first direction (D1). The first biasing section (75) biases the supporting section (71) in the first direction (D1) to press the charging roller (65) against the image bearing member (50). The second biasing section (90) biases the supporting section (71 toward the guide (73).

Abstract: A cleaning device includes a toner storing container that stores a collected toner, a conveyance screw that conveys toner in the toner storing container, and a toner crushing member that crushes the toner accumulated in the toner storing container. The toner crushing member is formed so as to include: a supporting portion being attached above a rotation axis of the conveyance screw; and a plurality of elastic pieces each extending from the supporting portion toward the conveyance screw and being swung by a fin that rotates in association with the rotation of the conveyance screw. Each of the elastic pieces is formed with a raised portion rising toward the seal member, so that the elastic pieces come in contact with the seal member.

Abstract: A cleaning device includes a toner storing container that stores a collected toner, a conveyance screw that conveys toner in the toner storing container, and a toner crushing member that crushes the toner accumulated in the toner storing container. The toner crushing member is formed so as to include: a supporting portion being attached above a rotation axis of the conveyance screw; and a plurality of elastic pieces each extending from the supporting portion toward the conveyance screw and being swung by a fin that rotates in association with the rotation of the conveyance screw. Each of the elastic pieces is formed with a raised portion rising toward the seal member, so that the elastic pieces come in contact with the seal member.

Abstract: A charging device (51) includes a charging roller (65), a supporting section (71), a guide (73), a first biasing section (75), and a second biasing section (90). The charging roller (65) charges an image bearing member (50). The supporting section (71) supports the charging roller (65) such that the charging roller (65) is rotatable. The guide (73) guides the supporting section (71) in a first direction (D1). The first biasing section (75) biases the supporting section (71) in the first direction (D1) to press the charging roller (65) against the image bearing member (50). The second biasing section (90) biases the supporting section (71 toward the guide (73).

Abstract: An image forming apparatus includes a housing, a photosensitive drum, a cleaning member, a driving transmission portion, and a movement mechanism. The photosensitive drum is rotatably supported by the housing about a first shaft portion. The driving transmission portion transmits a rotation driving force to the photosensitive drum. The movement mechanism reciprocates the photosensitive drum in an axial direction. The movement mechanism includes a first rotation gear, a second rotation gear, a first intermediate gear, and a second intermediate gear. The first rotation gear integrally rotates with the photosensitive drum. The second rotation gear has teeth different in number from teeth of the first rotation gear and rotates with a predetermined speed difference relative to the first rotation gear. The first and second intermediate gears are a pair of rotation gears rotatable about a second shaft portion parallel to the first shaft portion.

Abstract: An image forming apparatus includes: a displacement member supported so as to be displaceable; and a drive mechanism. The drive mechanism is a mechanism configured to displace the displacement member between a first position away from a fall path of a movement path for a powdery developer and a second position at which at least a part of the displacement member enters the fall path.

Abstract: An image forming apparatus includes a housing, a photosensitive drum, a cleaning member, a driving transmission portion, and a movement mechanism. The photosensitive drum is rotatably supported by the housing about a first shaft portion. The driving transmission portion transmits a rotation driving force to the photosensitive drum. The movement mechanism reciprocates the photosensitive drum in an axial direction. The movement mechanism includes a first rotation gear, a second rotation gear, a first intermediate gear, and a second intermediate gear. The first rotation gear integrally rotates with the photosensitive drum. The second rotation gear has teeth different in number from teeth of the first rotation gear and rotates with a predetermined speed difference relative to the first rotation gear. The first and second intermediate gears are a pair of rotation gears rotatable about a second shaft portion parallel to the first shaft portion.

Abstract: An image forming apparatus includes: a displacement member supported so as to be displaceable; and a drive mechanism. The drive mechanism is a mechanism configured to displace the displacement member between a first position away from a fall path of a movement path for a powdery developer and a second position at which at least a part of the displacement member enters the fall path.

Abstract: An image forming apparatus includes a waste toner case, an optical sensor, a cover and a shading member. The waste toner case is attachably/detachably provided in an apparatus main body via an opening part. The waste toner case collects a waste toner ejected from an image forming part forming an image by a toner. The optical sensor detects whether or not the waste toner case is filled with the waste toner. The cover closes the opening part of the apparatus main body. The shading member is arranged between the cover and optical sensor. The shading member covers the optical sensor in a state where the cover is closed.

Abstract: An image forming apparatus includes an image forming unit, a waste toner accommodating unit, a movement member, and a driving mechanism. The image forming unit forms an image by using a toner. The waste toner accommodating unit accommodates a waste toner after being used in the image forming unit. The movement member is supported so as to move in a direction parallel with a falling direction of the waste toner in a toner falling path, through which the waste toner falls, of a movement path of the waste toner that moves from the image forming unit to the waste toner accommodating unit. The driving mechanism reciprocates the movement member in the direction parallel with the falling direction of the waste toner.

Abstract: An image forming apparatus includes an image forming unit, a waste toner accommodating unit, a movement member, and a driving mechanism. The image forming unit forms an image by using a toner. The waste toner accommodating unit accommodates a waste toner after being used in the image forming unit. The movement member is supported so as to move in a direction parallel with a falling direction of the waste toner in a toner falling path, through which the waste toner falls, of a movement path of the waste toner that moves from the image forming unit to the waste toner accommodating unit. The driving mechanism reciprocates the movement member in the direction parallel with the falling direction of the waste toner.