Abstract: An image forming apparatus includes an image bearing member, an image forming portion, an endless belt, a plurality of stretching rollers including an inner roller, an outer roller, a position changing mechanism capable of changing a position of the inner roller to a first position and a second position positioned downstream of the first position with respect to a rotational direction of the endless belt, a feeding member, a feeding member driving portion, and a controller. A feeding start timing of a recording material by the feeding member depends on the position of the inner roller during transfer of a toner image onto the recording material.

Abstract: An image forming apparatus includes: an image bearing member configured to rotate; an image forming unit configured to form an image on the image bearing member; a detection unit configured to detect a test image formed on the image bearing member by the image forming unit; a controller configured to control a magnification of an image to be formed by the image forming unit based on a detection result of the test image by the detection unit.

Abstract: An image forming apparatus includes an image bearing member, an image forming portion, an endless belt, a plurality of stretching rollers including an inner roller, an outer roller, a position changing mechanism capable of changing a position of the inner roller to a first position and a second position positioned downstream of the first position with respect to a rotational direction of the endless belt, a feeding member, a feeding member driving portion, and a controller. A feeding start timing of a recording material by the feeding member depends on the position of the inner roller during transfer of a toner image onto the recording material.

Abstract: An image forming apparatus includes an image bearing member, an image forming portion, an endless belt, a plurality of stretching rollers including an inner roller, an outer roller, a position changing mechanism capable of changing a position of the inner roller to a first position and a second position positioned downstream of the first position with respect to a rotational direction of the endless belt, a feeding member, a feeding member driving portion, and a controller. A feeding start timing of a recording material by the feeding member depends on the position of the inner roller during transfer of a toner image onto the recording material.

Abstract: An image forming apparatus includes an image bearing member, an image forming portion, an endless belt, a plurality of stretching rollers including an inner roller, an outer roller, a position changing mechanism capable of changing a position of the inner roller to a first position and a second position positioned downstream of the first position with respect to a rotational direction of the endless belt, a feeding member, a feeding member driving portion, and a controller. A feeding start timing of a recording material by the feeding member depends on the position of the inner roller during transfer of a toner image onto the recording material.

Abstract: An image forming apparatus includes an image forming portion, a rotatable intermediary transfer belt, a plurality of stretching rollers, an outer roller, a moving mechanism capable of moving a position of the inner roller between a first position and a second position, a recording material feeding member, a driving source, and a controller. The controller controls the driving source so that when an image is formed in a state in which the inner roller is in a first position, a speed ratio Vp/Vb wherein Vp is a driving speed of the feeding member and Vb is a driving speed of the intermediary transfer belt is a first speed ratio, and when the image is formed in a state in which the inner roller is in a second position, the speed ratio Vp/Vb is a second speed ratio smaller than the first speed ratio.

Abstract: An image forming apparatus includes a movable endless belt, a first image bearing member, second image bearing members provided upstream of the first image bearing member with respect to a movement direction of the belt, a first transfer roller, second transfer rollers, an auxiliary roller provided upstream of a most upstream second transfer roller of the second transfer rollers with respect to the movement direction of the belt, and an executing portion capable of executing an operation in a full-color mode in a first roller arrangement and an operation in a monochromatic mode in a second roller arrangement.

Abstract: An image forming apparatus includes a movable endless belt, a first image bearing member, second image bearing members provided upstream of the first image bearing member with respect to a movement direction of the belt, a first transfer roller, second transfer rollers, an auxiliary roller provided upstream of a mostupstream second transfer roller of the second transfer rollers with respect to a movement direction of the belt, and an executing portion capable of executing an operation in a full-color mode in a first roller arrangement and an operation in a monochromatic mode in a second roller arrangement.

Abstract: A control part provided in an image forming apparatus controls a moving unit so as to cause a secondary transfer rotary member to move from an intermediate position to an abutment position at a first moving speed in the case of bringing the secondary transfer rotary member into abutment against an intermediate transfer member during an exposure period or a primary transfer period, and to cause the secondary transfer rotary member to move from a separation position to the abutment position at a second moving speed higher than the first moving speed in the case of bringing the secondary transfer rotary member into abutment against the intermediate transfer member during a period other than the exposure period and the primary transfer period. Thus, the productivity can be prevented from being degraded while a load change at a time of the abutment of the secondary transfer rotary member is reduced.

Abstract: A control part provided in an image forming apparatus controls a moving unit so as to cause a secondary transfer rotary member to move from an intermediate position to an abutment position at a first moving speed in the case of bringing the secondary transfer rotary member into abutment against an intermediate transfer member during an exposure period or a primary transfer period, and to cause the secondary transfer rotary member to move from a separation position to the abutment position at a second moving speed higher than the first moving speed in the case of bringing the secondary transfer rotary member into abutment against the intermediate transfer member during a period other than the exposure period and the primary transfer period. Thus, the productivity can be prevented from being degraded while a load change at a time of the abutment of the secondary transfer rotary member is reduced.