An image forming apparatus includes a printing unit, first and second stacking units, first and second conveyance units, and a control unit. When the first conveyance unit conveys a sheet to the first stacking unit, the printing unit prints an image on a first number of sheets as first sheets in a first printing operation and prints the image on the first sheets in a second printing operation. When the second conveyance unit conveys the sheet to the second stacking unit, the printing unit prints the image on a second number of sheets, greater than the first number of sheets, as second sheets in the first printing operation and prints the image on the second sheets in the second printing operation. A number of sheets printed per unit time in the second printing operation is less than a number of sheets printed per unit time in the first printing operation.

A packaging machine may include a foil transport device and a controlling system for controlling an operation of at least one drive unit of the foil transport device. The controlling system is designed to activate the drive unit during a production run of the packaging machine on the basis of a speed- and/or temperature-dependent friction moment characteristic curve detected by means of a rotationally driven measurement run carried out by the drive unit. The disclosure furthermore relates to a method for controlling a drive unit of a foil transport device.

A sheet feed apparatus includes a sheet feed cassette, an air blowing device, and an air blowing control portion. The air blowing device blows warm air to a sheet stack in the sheet feed cassette. The air blowing control portion controls the air blowing device to adjust an air volume and a temperature of the warm air. The air blowing control portion adjusts the air volume and the temperature of the warm air in accordance with the amount of sheets in the sheet feed cassette.

The invention provides a heat-shrinkable polyester-based film roll obtained by winding a heat-shrinkable polyester-based film with a shrinkage ratio of 30% or more in a film main shrinkage direction in hot water at 90° C. for 10 seconds. The film roll has a winding length of 2000-25000 m and a width of 400-2500 mm. The film has a thickness of 5-40 μm. In thickness unevenness in a width direction of the film on a surface layer of the film roll, there are positions having concave thickness patterns, and in a concave portion that has a maximum thickness difference (maximum concave portion), thickness unevenness in the maximum concave portion, which is obtained from the maximum thickness difference in the maximum concave portion and an average thickness of the film is 10% or less. The winding hardness of the surface layer of the film roll is 400-800.

An example paper feed device includes a tray to feed printing paper, a magnetic force generation element to generate a magnetic flux, a 3D magnetic sensor to detect changes in the a density of the magnetic flux generated by the magnetic force generation element in each of three axes, and a controller. The tray has a movable element that is movable in relation to the printing paper. Either the magnetic force generation element or the 3D magnetic sensor is attached to the movable element. The controller determines the position of the movable element based on a detection signal received from the 3D magnetic sensor.

An example paper feed device includes a tray to feed printing paper, a magnetic force generation element to generate a magnetic flux, a 3D magnetic sensor to detect changes in the a density of the magnetic flux generated by the magnetic force generation element in each of three axes, and a controller. The tray has a movable element that is movable in relation to the printing paper. Either the magnetic force generation element or the 3D magnetic sensor is attached to the movable element. The controller determines the position of the movable element based on a detection signal received from the 3D magnetic sensor.

A web handling apparatus is disclosed. The web handling apparatus includes a first web guide to engage a print medium, a second web guide to engage the print medium to adjust a contact area between the first web guide and the print medium upon moving between a plurality of points on a guide path and a third web guide to engage the print medium to form a web path with the first web guide.

Provided is a roll body capable of effectively suppressing the occurrence of a telescope phenomenon even if the ambient temperature during transportation and storage of the roll body becomes higher than that during production of the roll body. A roll body RB according to the present invention configured by winding a belt-shaped web around a winding core that thermally expands or contracts due to an influence of a surrounding environment is characterized in that a linear expansion coefficient of the web in a thickness direction is in a range of 60 to 150 times a linear expansion coefficient of the web in a longitudinal direction, and the winding core has a linear expansion coefficient in a range of 20×10.sup.−6/K to 100×10.sup.−6/K and a Young's modulus in a range of 0.2 GPa to 0.5 GPa.

A sheet accommodating apparatus includes an apparatus body, a first cassette to be drawn out in a draw-out direction with respect to the apparatus body, a second cassette disposed adjacent to the first cassette in a vertical direction, a holder member attached to the apparatus body, and a first light emitting member and a second light emitting member that are supported by the holder member. The first cassette includes a first accommodating container and a first cover. The second cassette includes a second accommodating container and a second cover. The first cover has a first hole in a position opposing the first light emitting member such that the light emitted from the first light emitting member passes therethrough. The second cover has a second hole provided in a position opposing the second light emitting member such that the light emitted from the second light emitting member passes therethrough.

A sheet accommodating apparatus includes an apparatus body, a first cassette to be drawn out in a draw-out direction with respect to the apparatus body, a second cassette disposed adjacent to the first cassette in a vertical direction, a holder member attached to the apparatus body, and a first light emitting member and a second light emitting member that are supported by the holder member. The first cassette includes a first accommodating container and a first cover. The second cassette includes a second accommodating container and a second cover. The first cover has a first hole in a position opposing the first light emitting member such that the light emitted from the first light emitting member passes therethrough. The second cover has a second hole provided in a position opposing the second light emitting member such that the light emitted from the second light emitting member passes therethrough.