Abstract: 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 a sheet contained in the cassette for each row; and a control unit for, when the absence of a 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.

Abstract: A sheet feeder includes a feeder for feeding a sheet, a cassette for containing a plurality of stacks of small sized sheets side by side therein, the cassette including a plurality of biasing members 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 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 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.

Abstract: An image forming apparatus has a low body and an upper body connected to the lower body rotatable about a pivot. The upper body carries an image forming device. The lower body carries a copy paper storage unit and a paper feeding device for feeding a copy paper sheet from the paper storage unit to the image forming device. The paper feeding device is provided with a paper inverting device between the paper storage unit and the image bearing device for inverting the copy paper sheet fed from the paper storage unit. The paper feeding device is exposed to the operator when the upper body is opened.

Abstract: A cassette is attachable to an image forming apparatus including a feed roller. The cassette is provided with a push-up member for pushing up leading edges of sheets placed in the cassette so as to bring the uppermost one of the contained sheets into contact with the feed roller, and a restricting member for restricting displacement of the contained sheets from a specified position. By attaching thus constructed cassette to the image forming apparatus, sheets can be fed properly by the feed roller.

Abstract: In a time period from the time point where the forward end of a paper sheet fed from a pair of paper separation rollers reaches a registration roller to the time point where the registration roller is driven, when the load torque exerted on a forward roller is not less than second regulated torque, the transmission of power to the forward roller is released by a torque limiter provided for the forward roller. In this case, therefore, the force of paper feeding produced by the pair of paper separation rollers is regulated. Consequently, a suitable force of paper feeding can be applied to the paper sheet, thereby to make it possible to regulate the paper sheet straight in the direction of paper feeding as well as to prevent the paper sheet from continuing to be fed even if the amount of deflection of the paper sheet is saturated between the pair of paper separation rollers and the registration roller to prevent the paper sheet from being wrinkled.

Abstract: A sheet transport device is provided with a plurality of sheet transport paths arranged in parallel to one another and a sheet transport assembly for transporting a sheet along the sheet transport path. The transport assembly includes a drive shaft extending normal to the plurality of sheet transport paths, a roller member mounted on the drive shaft in a position corresponding to each of the plurality of sheet transport paths, and a transmission mechanism provided between the drive shaft and roller member for transmitting the rotational force of the drive shaft rotating in a sheet transport direction to the roller member and for shutting off transmission of the rotational force of the roller member rotating in the sheet transport direction to the drive shaft. Accordingly, the misalignment of sheets to be transported simultaneously can be readily corrected.

Abstract: An image-forming machine having a conveying passage for conveying a sheet material through a transfer zone, a first and a second feed device for feeding the sheet material to the conveying passage, a first feed passage for conducting the sheet material delivered from the first feed device to the conveying passage, a second feed passage for conducting the sheet material delivered from the second feed device to the conveying passage, and a first and a second opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first and second opening-closing members.

Abstract: An image-forming machine comprising a conveying passage for conveying a sheet material through a transfer zone, a first and a second feed system for feeding the sheet material to the conveying passage, a first feed passage for conducting the sheet material delivered from the first feed system to the conveying passage, a second feed passage for conducting the sheet material delivered from the second feed system to the conveying passage, and a first and a second opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first and second opening-closing members.

Abstract: A paper delivery apparatus for delivering paper to a predetermined place by driving a roller support shaft with a the paper coming in contact with roller attached to the roller support shaft. The roller support shaft and the drive shaft are connected to each other between a pair of lateral plates. Bearings are attached to the roller support shaft at both ends thereof and are axially movably supported by bearing support members. The roller support shaft together with the bearings may be readily removed from the bearing support members by moving the roller support shaft or the bearings in the axial direction.