摘要:
An image forming apparatus includes a contact member supplied with voltage by a voltage application device, to contact an object; a rotary member rotatable about a rotation fulcrum shaft fixed to an image forming apparatus, to support the contact member; an biasing member to urge the rotary member to press the contact member against the object; a rotary conductive member fixed to the rotary member and connected electrically to the contact member; a main body side conductive member fixed to the rotation fulcrum shaft at the main body side and connected electrically to the voltage application device; and a conductive connector provided along the rotation fulcrum shaft to contact the rotary conductive member in an axial direction to connect electrically the main body side conductive member and the rotary conductive member. A contact of the conductive connector and a contact of the rotary conductive member are unfixed.
摘要:
An image forming apparatus includes multiple image bearing members, toner image forming devices, and a transfer unit. The transfer unit includes an intermediate transfer belt entrained about a plurality of rollers and onto which toner images are transferred from the image bearing members, a reference member to position the transfer unit in place, a frame to hold the plurality of rollers a certain distance from the reference member, and a moving device including a holding member to hold movably one of the rollers relative to the frame to change the position of the roller between a multiple color mode for forming a multiple color image and a single color mode for forming a single color image so that the intermediate transfer belt contacts and separates from the image bearing member. As the holding member contacts the reference member, the intermediate transfer belt contacts the image bearing members.
摘要:
A transfer device includes a plurality of rollers, a rotatable intermediate transfer belt wound around and stretched between the rollers, a transfer member disposed in the inner loop of the belt and facing an image bearing member of an image forming apparatus disposed at an outer circumference of the belt, to transfer an image formed onto the surface of the image bearing member when contacting the intermediate transfer belt, and a position adjuster to adjust the position of the intermediate transfer belt at different positions relative to the image bearing member. The positions include a contact state in which the intermediate transfer belt applied with a predetermined tension contacts the image bearing member, a first separation state in which the tensioned intermediate transfer belt separates from the image bearing member, and a second separation state in which the intermediate transfer belt separates further away from the image bearing member.
摘要:
A transfer assembly includes a counter member having a contact face, an engagement/disengagement unit to engage and disengage the image carrying face of image carrying member and the contact face of counter member using a cam, a pressure device to apply force to a transfer nip between the image carrying face and contact face, and a recording medium feed device to feed the recording medium to the transfer nip. When the cam is at a first rotation position, the image carrying face and contact face are separated, and when the cam is at a second rotation position, the image carrying face and contact face contact. Before the recording medium enters the transfer nip, the cam rotates from the first rotation position toward the second rotation position. After the recording medium enters the transfer nip, the cam is at the second rotation position to press the image carrying face with the contact face.
摘要:
A transfer device includes a plurality of rollers, a rotatable intermediate transfer belt wound around and stretched between the rollers, a transfer member disposed in the inner loop of the belt and facing an image bearing member of an image forming apparatus disposed at an outer circumference of the belt, to transfer an image formed onto the surface of the image bearing member when contacting the intermediate transfer belt, and a position adjuster to adjust the position of the intermediate transfer belt at different positions relative to the image bearing member. The positions include a contact state in which the intermediate transfer belt applied with a predetermined tension contacts the image bearing member, a first separation state in which the tensioned intermediate transfer belt separates from the image bearing member, and a second separation state in which the intermediate transfer belt separates further away from the image bearing member.
摘要:
An image forming apparatus includes an image bearing member to bear a toner image charged with a predetermined polarity, and a power source to apply a bias to a transfer portion to transfer the toner image from the image bearing member to a recording medium, a polarity of the bias being changed alternately. The toner image formed with toner of a plurality of colors is transferred in a color mode and the toner image formed with toner of a single color is transferred in a monochrome mode. The bias includes a peak voltage with a polarity that returns toner from the recording medium to the image bearing member. An absolute value of the peak voltage in the color mode is equal to or greater than an absolute value of the peak voltage in the monochrome mode.
摘要:
A transfer device includes an image carrier, a transfer roller, and a moving unit. The moving unit moves the transfer roller between a nip formation state in which the transfer roller forms a transfer nipping portion in contact with the image carrier and a separated state in which the transfer roller is separated from the image carrier. In a contact operation of bringing the transfer roller into contact with the image carrier via the recording medium, the moving unit moves the transfer roller toward the image carrier at a moving velocity slower than that in a pressing operation of generating a predetermined nipping pressure by further moving the transfer roller toward the image carrier after the contact operation. The moving unit causes the recording medium to enter the transfer nipping portion in the contact operation.
摘要:
An image forming apparatus includes multiple image bearing members, toner image forming devices, and a transfer unit. The transfer unit includes an intermediate transfer belt entrained about a plurality of rollers and onto which toner images are transferred from the image bearing members, a reference member to position the transfer unit in place, a frame to hold the plurality of rollers a certain distance from the reference member, and a moving device including a holding member to hold movably one of the rollers relative to the frame to change the position of the roller between a multiple color mode for forming a multiple color image and a single color mode for forming a single color image so that the intermediate transfer belt contacts and separates from the image bearing member. As the holding member contacts the reference member, the intermediate transfer belt contacts the image bearing members.
摘要:
An image forming apparatus includes a transfer unit configured to transfer a toner image onto a recording medium; a power supply unit configured to apply one of a superimposed voltage in which an alternating-current voltage and a first direct-current voltage are superimposed and a second direct-current voltage to the transfer unit; and a power supply control configured to, when the power supply unit outputs the superimposed voltage, instruct the power supply unit to output the first direct-current voltage at a first timing, and, when the power-supply unit outputs the second direct-current voltage, instruct the power-supply unit to output the second direct-current voltage at a second timing which is later than the first timing.
摘要:
To provide an image forming apparatus capable of increasing the life of a rotating cam while preventing the occurrence of a shock jitter and transfer failure. The image forming apparatus is configured to execute a forced movement process for rotating the rotating cam to forcibly move a secondary transfer roller against a biasing force of a bias coil spring at a pre-entry timing prior to the entry of the front edge of a recording sheet into a secondary transfer position, and a pressure intensifying process for rotating the rotating cam to increase transfer pressure at a timing immediately after the entry of the front edge of the recording sheet into the secondary transfer position. As the forced movement process, the image forming apparatus executes, alternately, a first forced movement process for normally driving and rotating the rotating cam, and a second forced movement process for inversely driving and rotating the rotating cam, at a predetermined timing.