摘要:
In a recording sheet conveying device comprising: a dielectric sheet which moves at a predetermined speed while electrostatically retaining a recording sheet on the outer surface thereof; a charger positioned on the side of the inner surface of the dielectric sheet, to induce electrostatic attraction forces between the dielectric sheet and the recording sheet; and a deflector roll having an electrically conductive layer as an outer surface thereof, the deflector roll being confronted with the charger and adapted to push the recording sheet against the dielectric sheet, the number of electric charges provided by the charger is so adjusted that electrostatic attraction forces acting on the rear end portion of the recording sheet are weaker than those acting on the front end portion of the recording sheet, whereby the recording sheet is prevented from being wrinkled when electrostatically retained on the dielectric sheet.
摘要:
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.
摘要:
An information processor includes a storage unit storing a first coefficient in correspondence with a characteristic of a sheet of paper, a first acquisition unit acquiring a first signal based on the water content of a first sheet of paper not having an image formed thereon, a second acquisition unit acquiring a second signal based on the water content of the first sheet of paper having an image formed thereon and being heated for fixing, a determination unit determining the characteristic of the first sheet of paper, a first calculation unit calculating a variation in water content of the first sheet of paper using the difference between the first signal and the second signal and the first coefficient stored in correspondence with the determined characteristic, and a second calculation unit calculating an expansion and contraction ratio of the first sheet of paper using the variation in water content.
摘要:
A length measurement apparatus including: a measurement portion that measures a sheet length based on a rotational amount of a length measurement roll for a first detection period in which first and third sensors detect the sheet, and a sheet length based on a rotational amount of the length measurement roll for a second detection period in which the second sensor and any one of the first and third sensors detect the sheet, the any one of the first and third sensors being disposed at a position opposite to the second sensor via the length measurement roll; and a whole length calculation portion that selects the sheet length nearer to integral multiples of the circumference length of the length measurement roll from the sheet lengths measured for the first and second detection periods, and calculates the whole length of the sheet by using the selected sheet length.
摘要:
A sheet length measurement apparatus including: a rotating member that comes in contact with a recording sheet conveyed on a conveying path, and rotates along with the conveyance of the recording sheet; a rotation amount detector that detects a rotational amount of the rotating member; a fixing support member that fixedly supports an rotating shaft of the rotating member at a fixed position; an opposed member that is disposed opposite to the rotating member so as to hold the recording sheet between the rotating member and the opposed member, the opposed member being disposed so that the rotating member rotates along with the conveyance of the recording sheet; and a support member that supports the opposed member in a movable state in a direction to separate from or come in contact with a surface of the recording sheet.
摘要:
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.
摘要:
An image forming apparatus includes an image forming unit forming an image on a recording sheet; a transport unit transporting the recording sheet; a support surface supporting the recording sheet; a rotating member having an outer peripheral surface pressed against the support surface and rotationally following the recording sheet when the recording sheet passes through between the support surface and the outer peripheral surface; an ascertaining unit ascertaining a length of the recording sheet on the basis of an amount of rotation of the rotating member; and a restricting unit restricting a movement of the rotating member that moves toward the support surface after the recording sheet passes through between the support surface and the outer peripheral surface, the restricting unit preventing the outer peripheral surface, which comes into contact with the recording sheet, and the support surface from coming into contact with each other.
摘要:
An abnormality detecting device for a rotation body includes: a rotation body rotating while coming in contact with a sheet transported at a predetermined speed; an output unit outputting pulses of a number in proportion to a rotation amount of the rotation body; an acquisition unit acquiring periodic information associating a position of the rotation body during a single rotation and a period of each of the pulses corresponding to the position with each other, the periodic information being acquired based on the plural pulses outputted from the output unit along with the rotation of the rotation body at the predetermined speed; a memory storing the periodic information as reference periodic information; and an abnormality detector detecting an abnormality occurred in at least one of the rotation body and the output unit based on the reference periodic information and new periodic information acquired after the reference periodic information is acquired.
摘要:
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.
摘要:
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.