Abstract: A driving apparatus transmits a driving force from a drive source to a driven body via a multiple-stage gear train (including, for example, gears). In the multiple-stage gear train, the speed fluctuation phase of a mesh frequency occurring at each mesh point of the gear train including the gears to a target gear is set in a range in which the speed fluctuation amplitude of the target gear positioned downstream at the third stage or later is equal to or less than the speed fluctuation amplitude of the immediately preceding mesh gear positioned upstream. The invention also applies to an image formation apparatus using the drive as a drive of a driven body.

Abstract: A driving device for an image carrying member, e.g., a belt, is to be provided that causes no increase in size and cost of the device and sufficiently stabilizes the velocity of the image carrying member upon fluctuation in load, so as to suppress or prevent formation of an image defect referred to as so-called “banding”. A rotating member is made in contact with at least one of a driving force transmitting member and an image carrying member, which are arranged in a driving force transmission path for transmitting the driving force to the image carrying member, and the rotating member rotates in contact with the driving force transmitting member or the image carrying member, and providing, upon occurring fluctuation in velocity of the driving force transmitting member or the image carrying member, a viscous effect that suppresses the fluctuation in velocity.

Abstract: A driving apparatus transmits a driving force from a drive source to a driven body via a multiple-stage gear train (including, for example, gears). In the multiple-stage gear train, the speed fluctuation phase of a mesh frequency occurring at each mesh point of the gear train including the gears to a target gear is set in a range in which the speed fluctuation amplitude of the target gear positioned downstream at the third stage or later is equal to or less than the speed fluctuation amplitude of the immediately preceding mesh gear positioned upstream. The invention also applies to an image formation apparatus using the drive as a drive of a driven body.

Abstract: A registration pattern is formed on an intermediate transfer belt by using one photosensitive body. Pattern parts transferred onto the intermediate transfer belt vary in spacing due to speed variation occurring at the transfer time. The passing timing of the registration pattern is read through a read section placed downstream from the photosensitive body and speed (position) variation is sensed. The sense data is gotten over several cycles of the intermediate transfer belt and a low-frequency component caused by thickness unevenness of the intermediate transfer belt is extracted. The extracted data is subjected to the effects of variations at both the formation time and read time of the registration pattern and thus is corrected of calculating true speed (position) variation data. For example, a drive roll is controlled based on the data and an image is formed.

Abstract: A belt feeding device including a plurality of belt feeding rolls, a belt wrapped around the rolls, and at least a pair of guide members each having an edge guide surface against which either side edge of the belt abuts in crosswise movement of the belt. The outer circumferential surface of each roll is formed with a plurality of ring-shaped slits axially spaced a distance w from each other, each of the slits having a depth h and a width m. The values of h, m, and w are set so that a load to an axial displacement of the belt wrapped around the rolls at a position of each guide member becomes 80 N/mm or less. Accordingly, an edge force acting between either side edge of the belt and the corresponding guide member against which the side edge of the belt abuts can be reduced to 15N or less.