Abstract: An apparatus for measuring a length of a recording material, includes: a rotating member that rotates while contacting a conveyed recording material; a detecting section that detects a rotation amount of the rotating member; an information obtaining section that obtains at least one of information of an image formed on the recording material and information of the recording material; and a calculating section that calculates a length of the recording material in a direction of the conveyance, based on an output from the detecting section and the information obtained by the information obtaining section.

Abstract: A measuring device, wherein a feed-out member feeds out an uppermost one of plural sheet-shaped materials stacked on a base by rotating in contact with the uppermost sheet-shaped material, has a detector that detects a force imparted to the base and the sheet-shaped materials not in contact with the feed-out member, the force being generated by feeding-out the uppermost sheet-shaped material.

Abstract: A position detection apparatus includes: a moving member in contact with a detection object that moves following movement of the detection object; and a support member that rotatably supports the moving member; a detection unit that detects a positional change of the moving member, the moving member being acted on by a first force as a force to press the moving member against the detection object, a second force as a force to press the moving member substantially in a direction of a rotation shaft of the moving member, and a third force as a force to press the moving member in a direction substantially orthogonal to the direction of the rotation shaft of the moving member.

Abstract: A recording medium thickness measuring apparatus includes: an output value detection unit that detects an output value which fluctuates in accordance with thickness of a recording medium passing through a predetermined position of a transport path; and a calculation unit that calculates the thickness of the recording medium based on a first output value detected by the output value detection unit before passage of the recording medium and after passage of an immediately preceding recording medium in the predetermined position of the transport path, and a second output value detected by the output value detection unit while the recording medium is passing through the predetermined position.

Abstract: A sheet feed device includes an air flow generating part that generates an air flow for floating a sheet; a feed member that feeds a sheet by rotating, while applying a load to the top one of sheets stacked; and a transport condition sensing unit that is positioned not to obstruct an air flow generated by the air flow generating part and senses a transport condition of a sheet fed by the feed member.

Abstract: A sheet feeding apparatus includes: a multiple-feed detecting section that detects recording sheets to be transported by plural rolls in a direction; a separating section that separates an uppermost sheet of the recording sheets from the other; a slippage detecting section that detects a slippage of the uppermost recording sheet with respect to a roll; and a transporting-speed reduction suppressing section that suppresses a transporting-speed of the uppermost recording sheet from reducing from a value, the separation section including: a transporting roll that transports recording sheets in a transporting direction; and a separation roll that is placed to be opposed to and to be press-contacted with the transporting roll through a recording sheet, the transporting-speed reduction suppressing section changing a separation torque of the separation roll according based on a result of detection by the multiple-feed detecting section and a result of detection by the slippage detecting section.

Abstract: A measuring device, wherein a feed-out member feeds out an uppermost one of plural sheet-shaped materials stacked on a base by rotating in contact with the uppermost sheet-shaped material, has a detector that detects a force imparted to the base and the sheet-shaped materials not in contact with the feed-out member, the force being generated by feeding-out the uppermost sheet-shaped material.

Abstract: A sheet feeding apparatus includes a transport unit that transports a recording sheet from a storage unit, a separation unit, when stacked plural recording sheets are transported by the transport unit, separates a first recording sheet from the other recording sheets, and a push-back unit that can pivot from a separation action point to an end point of the storage unit and that pushes back ends of the other recording sheets to the storage unit during transport of the first recording sheet by applying to the other recording sheets a larger force in the direction opposite to the transport direction than a force applied to the other recording sheets in the transport direction, at a same time by applying to the first recording sheet a smaller force in the direction opposite to the transport direction than a force applied to the first recording sheet in the transport direction.

Abstract: A sheet feeding apparatus includes: a multiple-feed detecting section that detects recording sheets to be transported by plural rolls in a direction; a separating section that separates an uppermost sheet of the recording sheets from the other; a slippage detecting section that detects a slippage of the uppermost recording sheet with respect to a roll; and a transporting-speed reduction suppressing section that suppresses a transporting-speed of the uppermost recording sheet from reducing from a value, the separation section including: a transporting roll that transports recording sheets in a transporting direction; and a separation roll that is placed to be opposed to and to be press-contacted with the transporting roll through a recording sheet, the transporting-speed reduction suppressing section changing a separation torque of the separation roll according based on a result of detection by the multiple-feed detecting section and a result of detection by the slippage detecting section.

Abstract: A recording medium supply apparatus includes: a conveyance member that conveys a recording medium; a retard member, in contact with the conveyance member, that forms a contact portion between the conveyance member and the retard member and retards the recording medium by holding the recording medium in the contact portion; and a buckling prevention unit, configured to contact with the recording medium on the upstream side of the contact portion between the conveyance member and the retard member in a conveyance direction of the recording medium, that prevents buckling of the recording medium in the conveyance direction.

Abstract: A sheet feed device includes: a conveyor roller that rotates in a first direction; a separation roller rotatable in a second, reverse to the first direction, that nips a sheet with the conveyor roller; a sheet detector provided at a detecting position to detect a number of sheets; a pressure generator that generates a pressure to press the separation roller against the conveyor roller; a separation torque generator that generates a separation torque to convey the sheet on the separation roller in the second direction; and a controller that, if two or more sheets are detected, applies the pressure and/or the separation torque to the separation roller to separate the sheets until the detected number of sheets is decreased to be one, and that, after the number of sheets becomes one, controls the pressure and/or the separation torque to adjust a position of the sheet on the separation roller to a target position.

Abstract: A sheet feeding apparatus includes a transport unit that transports a recording sheet from a storage unit, a separation unit, when stacked plural recording sheets are transported by the transport unit, separates a first recording sheet from the other recording sheets, and a push-back unit that can pivot from a separation action point to an end point of the storage unit and that pushes back ends of the other recording sheets to the storage unit during transport of the first recording sheet by applying to the other recording sheets a larger force in the direction opposite to the transport direction than a force applied to the other recording sheets in the transport direction, at a same time by applying to the first recording sheet a smaller force in the direction opposite to the transport direction than a force applied to the first recording sheet in the transport direction.

Abstract: A sheet feed device includes: a conveyor roller that rotates in a first direction; a separation roller rotatable in a second, reverse to the first direction, that nips a sheet with the conveyor roller; a sheet detector provided at a detecting position to detect a number of sheets; a pressure generator that generates a pressure to press the separation roller against the conveyor roller; a separation torque generator that generates a separation torque to convey the sheet on the separation roller in the second direction; and a controller that, if two or more sheets are detected, applies the pressure and/or the separation torque to the separation roller to separate the sheets until the detected number of sheets is decreased to be one, and that, after the number of sheets becomes one, controls the pressure and/or the separation torque to adjust a position of the sheet on the separation roller to a target position.

Abstract: A device for measuring a surface potential at a photosensitive body including: a potential sensor for measuring surface potentials at a plurality of positions on the photosensitive body; a plurality of sample hold circuits; and an adder for adding each measured surface potential held in each sample hold circuit, or an adder which adds up each measured surface potential and average the sum. The addition or averaging of the measured values serves to eliminate eccentricity-induced errors and noise in the surface potential measurements, thereby allowing a correct surface potential to be obtained.

Abstract: A beam position control apparatus in which a light beam is led into a light detector from a light generating source through a movable reflector and positioning of the light beam is performed by a servo control circuit for feeding a signal from the light detector back to the movable reflector, comprises: an oscillator for oscillating in response to an initializing signal and moving the movable reflector to move the beam onto the light detector; and a control switch for separating the oscillator and the movable reflector from each other in response to the signal from the light detector, the oscillator and the control switch being arranged in the servo control circuit.

Abstract: A double beam scan type optical apparatus for use in a laser printer or the like. Such apparatus comprises two light sources and a lens system which provide scanning means for scanning a surface with parallel output light beams of the two light sources and beam distance controlling means for controlling the distance between the light beams. The reliability of the invention is improved by monitoring the intensity of the beams. Beam intensity checking means provide signals to verify that the intensity of each beam is maintained equal thus assuring that no abnormal conditions exist with the light sources or the lens system of the apparatus.

Abstract: A scanning apparatus for use in a laser beam printer or the like comprising a control means for varying the spacing between adjoining scanning beams of a plurality of laser beams, which further comprises a plurality of light sources, a means for changing intensity, including on/off states, of the beam from the light sources, and a rotating polygonal mirror for allowing the beams to scan the scanned plane in parallel, and is adapted, in accordance with the value of the pixel density of information to be recorded, such that, in the beam scanning direction, the area exposed to the beam is changed by changing the width of a beam intensity modulating pulse, and in the direction perpendicular to the beam scanning, the number of revolutions of the rotating polygonal mirror is changed.

Abstract: An optical scanner and method in which light beams from a plurality of sources are directed onto a medium to form a composite spot. The relative positions of the beams are detected and changed to change the diameter of the composite spot so that lines formed by such spots appear unbroken. The modulating times, intensities and number of sources of the beams can also be varied to provide a linear relation between the dither matrix and the picture element density.