摘要:
A sheet feeder includes a feeder for feeding a sheet, a cassette (4B) for containing a plurality of stacks of small sized sheets side by side therein, the cassette including a plurality of biasing members (42a,42b) for biasing the respective stacks of small sized sheets upwards so as to bring uppermost sheets of the respective stacks into contact with the feeder, a plurality of sheet detectors (1a,1b) arranged in positions corresponding to the respective stacks of sheets for detecting the height of the respective stacks of sheets contained in the cassette, and a controller (26) responsive to the plurality of sheet detectors for determining the absence of sheet in the cassette when at least one of the plurality of sheet detectors detects that the height of the stack has become lower than a predetermined height, and stopping a sheet feeding operation. This sheet feeder prevents the transfer device of an image forming apparatus from being smeared due to the fact that the small sized sheet is fed from only one stack.
摘要:
An image-forming machine comprising a conveying passage (51) for conveying a sheet material through a transfer zone, a first (66) and a second (68) feed means for feeding the sheet material to the conveying passage (51), a first feed passage (86) for conducting the sheet material delivered from the first feed means (66) to the conveying passage (51), a second feed passage (96) for conducting the sheet material delivered from the second feed means (68) to the conveying passage (51), and a first (124) and a second (126) opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first (124) and second (126) opening-closing members. Further provided are an improvement for suppressing noises, an improvement for preventing folding of a sheet material, an improvement for easily switching over to a mode of forming an image on both surfaces of a sheet material, an improvement for accurately conducting the sheet material from a reversal holding portion (382) to a return passage (384), and an improvement for positioning the sheet material received in the receiving-refeeding means (386) at a predetermined widthwise position in the above and other types of image-forming machines.
摘要:
An image-forming machine comprising a conveying passage (51) for conveying a sheet material through a transfer zone, a first (66) and a second (68) feed means for feeding the sheet material to the conveying passage (51), a first feed passage (86) for conducting the sheet material delivered from the first feed means (66) to the conveying passage (51), a second feed passage (96) for conducting the sheet material delivered from the second feed means (68) to the conveying passage (51), and a first (124) and a second (126) opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first (124) and second (126) opening-closing members. Further provided are an improvement for suppressing noises, an improvement for preventing folding of a sheet material, an improvement for easily switching over to a mode of forming an image on both surfaces of a sheet material, an improvement for accurately conducting the sheet material from a reversal holding portion (382) to a return passage (384), and an improvement for positioning the sheet material received in the receiving-refeeding means (386) at a predetermined widthwise position in the above and other types of image-forming machines.
摘要:
An image forming apparatus includes a mount portion which permits a cassette containing a plurality of stacks of sheets arranged side by side in rows to be mounted to the image forming apparatus; a feeder for feeding sheets side by side in a state where the cassette is mounted to the mount portion; an imaging assembly for forming an image on each of the sheets being fed side by side; a sheet sensor for detecting the presence or absence of sheet contained in the cassette for each row; and a control unit for, when the absence of sheet is detected in any of the rows, stopping at least an image forming operation along a corresponding transport path. Accordingly, even if all the sheets run out in any one of the rows, the corresponding transport path and the like can be prevented from getting smeared due to the image forming operation carried out despite the fact that no sheets are being fed.