Abstract: A belt device includes a first stretching member and a detector. The first stretching member stretches an endless belt capable of rotational movement. The detector detects a base of the belt and/or a density of a toner image on the belt. The first stretching member includes a first parallel area that is parallel to an axial direction, which is a direction of a rotation axis of the belt, and a first inclined area that is connected to an outer side of the first parallel area with respect to the axial direction and is inclined in a direction closer to the rotation axis. The detector detects a location corresponding to a first boundary between the first parallel area and the first inclined area or a location corresponding to a predetermined first adjacent area that is adjacent to and on an inner side of the first boundary.

Abstract: A belt device includes a first stretching member and a detector. The first stretching member stretches an endless belt capable of rotational movement. The detector detects a base of the belt and/or a density of a toner image on the belt. The first stretching member includes a first parallel area that is parallel to an axial direction, which is a direction of a rotation axis of the belt, and a first inclined area that is connected to an outer side of the first parallel area with respect to the axial direction and is inclined in a direction closer to the rotation axis. The detector detects a location corresponding to a first boundary between the first parallel area and the first inclined area or a location corresponding to a predetermined first adjacent area that is adjacent to and on an inner side of the first boundary.

Abstract: When a first unit is disposed at a position at which a transfer member comes into contact with an image carrier, the first unit is urged in a first urging direction intersecting a movement direction of a second unit by a second urging member disposed between the first unit and the second unit being movable between a first attachment position with respect to an image forming apparatus body and a second attachment position different from the first attachment position.

Abstract: An electric connection structure includes: a connection terminal that includes a compression coil spring part; a terminal holding part that includes a base supporting one end surface side of the compression coil spring part and a guide part provided along an outer surface of the compression coil spring part; and a lead wire that includes a folded-back part in one end part. In the electric connection structure, the folded-back part is held between the one end surface of the compression coil spring part and a support part and two lines of the folded-back part are brought into contact with the connection terminal, and the connection terminal and the lead wire are thereby electrically connected.

Abstract: A secondary transfer portion includes a transfer roller, a fixing member, a movable member, and a detector. The transfer roller is configured to rotate about an axis thereof when the secondary transfer portion is attached to an apparatus body. The fixing member is fixed to the axial end portion of the transfer roller. The movable member is caught on the fixing member. The detector is configured to indicate different detection states depending on a position of the movable member. The fixing member and the movable member are connected to each other through a guide mechanism (a guide groove and a guide protrusion) that is configured to move the movable member in an axial direction of the transfer roller. The movable member is moved to a detection position of the detector by rotation of the transfer roller.

Abstract: When a first unit is disposed at a position at which a transfer member comes into contact with an image carrier, the first unit is urged in a first urging direction intersecting a movement direction of a second unit by a second urging member disposed between the first unit and the second unit being movable between a first attachment position with respect to an image forming apparatus body and a second attachment position different from the first attachment position.

Abstract: An electric connection structure includes: a connection terminal that includes a compression coil spring part; a terminal holding part that includes a base supporting one end surface side of the compression coil spring part and a guide part provided along an outer surface of the compression coil spring part; and a lead wire that includes a folded-back part in one end part. In the electric connection structure, the folded-back part is held between the one end surface of the compression coil spring part and a support part and two lines of the folded-back part are brought into contact with the connection terminal, and the connection terminal and the lead wire are thereby electrically connected.

Abstract: A secondary transfer portion includes a transfer roller, a fixing member, a movable member, and a detector. The transfer roller is configured to rotate about an axis thereof when the secondary transfer portion is attached to an apparatus body. The fixing member is fixed to the axial end portion of the transfer roller. The movable member is caught on the fixing member. The detector is configured to indicate different detection states depending on a position of the movable member. The fixing member and the movable member are connected to each other through a guide mechanism (a guide groove and a guide protrusion) that is configured to move the movable member in an axial direction of the transfer roller. The movable member is moved to a detection position of the detector by rotation of the transfer roller.

Abstract: An image forming apparatus includes: a roller arranged in a position between a drive roller and an idle roller and downstream from the drive roller in a rotation direction of an intermediate transfer belt while pressing an outer surface of the belt; and a density measuring portion arranged between the drive roller and the roller applying pressure. The density measuring portion optically detects the density of a test patch formed on the outer surface and in a given position of a width direction of the belt. The density measuring portion includes: an optical sensor provided above the outer surface of the belt; and a support member abutting on an inner surface of the belt in a position in which the support member faces the optical sensor across the belt in the rotation direction.

Abstract: An image forming apparatus includes: a roller arranged in a position between a drive roller and an idle roller and downstream from the drive roller in a rotation direction of an intermediate transfer belt while pressing an outer surface of the belt; and a density measuring portion arranged between the drive roller and the roller applying pressure. The density measuring portion optically detects the density of a test patch formed on the outer surface and in a given position of a width direction of the belt. The density measuring portion includes: an optical sensor provided above the outer surface of the belt; and a support member abutting on an inner surface of the belt in a position in which the support member faces the optical sensor across the belt in the rotation direction.

Abstract: An image forming apparatus determines the amount of cleaning toner that is supplied to each of an intermediate transfer belt 31 and a secondary transfer belt 42 based on the number of sheets that have been fed with the pick-up side of the sheet opposed to the intermediate transfer belt 31 and the number of sheets that have been fed with the pick-up side of the sheet opposed to the secondary transfer belt 42; integrally forms on the intermediate transfer belt 31 cleaning toner images that are supplied to each of the intermediate transfer belt 31 and the secondary transfer belt 42; and switches the application and the stop application of the transfer voltage for transferring the toner image from the intermediate transfer belt 31 to the secondary transfer roller 41 at a timing corresponding to the determined amount of toner.

Abstract: An electrostatic charger device according to this invention includes a cleaner member, an operating rod, a guide portion, and a bending member. The cleaner member is configured to clean an electrode housed in a housing by pressing against the electrode. The operating rod has one end in a longitudinal direction to which the cleaner member is fixed. The guide portion is disposed at one end of the housing in a primary scanning direction and has a through-hole through which the operating rod extends in the longitudinal direction, the guide portion supporting the operating rod to enable the cleaner member to reciprocate between a first position and a second position. The bending member is configured to bend the operating rod in such a manner that an intermediate portion of the operating rod projects away from an image bearing member when the cleaner member is in the first position.

Abstract: A mounting structure includes a supporting member and an engagement member. The supporting member includes a first engaging section at one edge portion and a second engaging section at the other edge portion, and supports or positions an object to support. The engagement member includes a first engagement section capable of engaging with the first engaging section and a second engagement section capable of engaging with the second engaging section, and is a member for holding the supporting member with the supporting member being mounted onto the engagement member. Also, the supporting member supports or positions the object to support with the first engaging section and the second engaging section respectively engaging with the first engagement section and the second engagement section. The first engaging section has a higher rigidity than the first engagement section. The second engaging section has a higher rigidity than the second engagement section.

Abstract: An electrostatic charger device according to this invention includes a cleaner member, an operating rod, a guide portion, and a bending member. The cleaner member is configured to clean an electrode housed in a housing by pressing against the electrode. The operating rod has one end in a longitudinal direction to which the cleaner member is fixed. The guide portion is disposed at one end of the housing in a primary scanning direction and has a through-hole through which the operating rod extends in the longitudinal direction, the guide portion supporting the operating rod to enable the cleaner member to reciprocate between a first position and a second position. The bending member is configured to bend the operating rod in such a manner that an intermediate portion of the operating rod projects away from an image bearing member when the cleaner member is in the first position.

Abstract: A mounting structure includes a supporting member and an engagement member. The supporting member includes a first engaging section at one edge portion and a second engaging section at the other edge portion, and supports or positions an object to support. The engagement member includes a first engagement section capable of engaging with the first engaging section and a second engagement section capable of engaging with the second engaging section, and is a member for holding the supporting member with the supporting member being mounted onto the engagement member. Also, the supporting member supports or positions the object to support with the first engaging section and the second engaging section respectively engaging with the first engagement section and the second engagement section. The first engaging section has a higher rigidity than the first engagement section. The second engaging section has a higher rigidity than the second engagement section.

Abstract: The transfer portion for use in an image forming apparatus includes: an intermediate transfer belt having a toner image temporarily transferred from a photoreceptor drum; roller members that support and stretch the intermediate transfer belt; and strip-like guide elements that guide conveyance of the intermediate transfer belt. The guide elements are provided on the inner peripheral surface of the intermediate transfer belt with the first and second ends opposed to and arranged a predetermined gap apart from each other. Each of the first and second ends is formed with a first (second) perpendicular surface that is perpendicular to the advancing direction of the belt and a first (second) inclined surface that is inclined relative to the belt advancing direction. The first and second perpendicular surfaces are formed in such a position that the first and second ends become tapered by the first and second inclined surfaces, respectively.

Abstract: The transfer portion for use in an image forming apparatus includes: an intermediate transfer belt having a toner image temporarily transferred from a photoreceptor drum; roller members that support and stretch the intermediate transfer belt; and strip-like guide elements that guide conveyance of the intermediate transfer belt. The guide elements are provided on the inner peripheral surface of the intermediate transfer belt with the first and second ends opposed to and arranged a predetermined gap apart from each other. Each of the first and second ends is formed with a first (second) perpendicular surface that is perpendicular to the advancing direction of the belt and a first (second) inclined surface that is inclined relative to the belt advancing direction. The first and second perpendicular surfaces are formed in such a position that the first and second ends become tapered by the first and second inclined surfaces, respectively.