Image forming apparatus with endless belt, stretching rollers to stretch endless belt, and position changing mechanism to move inner roller of stretching rollers
AssigneeCanon Kabushiki Kaisha
InventorTomoya Inuzuka
Life of this patent
Estimating the term…
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.
Claims27
An image forming apparatus comprising:
- an image bearing member configured to bear a toner image;
- an image forming portion configured to form the toner image on the image bearing member;
- an endless belt onto which the toner image formed on the image bearing member is transferred at a primary transfer portion;
- a plurality of stretching rollers including an inner roller, the plurality of stretching rollers being configured to stretch the endless belt;
- an outer roller configured to form a secondary transfer portion in cooperation with the inner roller where the toner image is transferred from the endless belt onto a recording material;
- a position changing mechanism configured to move the inner roller to change a position of the secondary transfer portion with respect to a circumferential direction of the inner roller, the position changing mechanism being capable of changing a position of the inner roller to a plurality of positions including 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 configured to feed the recording material to the secondary transfer portion;
- a feeding member driving portion configured to drive the feeding member;
- and
- a controller configured to control the feeding member driving portion,
- wherein the control of the feed member driving portion by the controller depends on the position of the inner roller when the toner image is transferred to the recording material.
An image forming apparatus comprising:
- an image bearing member configured to bear a toner image;
- an image forming portion configured to form the toner image on the image bearing member;
- an endless belt onto which the toner image formed on the image bearing member is transferred at a primary transfer portion;
- a plurality of stretching rollers including an inner roller, the plurality of stretching rollers being configured to stretch the endless belt;
- an outer roller configured to form a secondary transfer portion in cooperation with the inner roller where the toner image is transferred from the endless belt onto a recording material;
- a position changing mechanism configured to move the inner roller to change a position of the secondary transfer portion with respect to a circumferential direction of the inner roller, the position changing mechanism being capable of changing a position of the inner roller to a plurality of positions including 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 configured to feed the recording material to the secondary transfer portion;
- a feeding member driving portion configured to drive the feeding member;
- and
- a controller configured to control a time difference from a predetermined reference timing to a feeding start timing of the recording material by the feeding member,
- wherein the time difference depends on the position of the inner roller during transfer of the toner image onto the recording material.
Dependencies are inferred from the claim text.