Abstract:
A fixing device includes a first fixing section, a second fixing section, the first fixing section and the second fixing section forming a fixing nip therebetween, a nip width adjusting section capable of adjusting a nip width of the fixing nip, a rotation speed detecting section that detects a rotation speed of the second fixing section, and a hardware processor that controls the nip width adjusting section to make the nip width equal to a predetermined reference nip width.
Abstract:
An image forming apparatus includes: an image holder that holds a toner image; a transferer that is disposed opposite to the image holder so as to be in contact with the image holder and transfers the toner image from the image holder onto a recording sheet that is going through a contact part where the transferer contacts the image holder, by applying a transfer voltage between the transferer and the image holder; a first power source that applies a voltage of a first polarity to the image holder; and a second power source that applies a voltage of a second polarity, which is reverse to the first polarity, to the transferer.
Abstract:
A paper feed apparatus is capable of correcting the skew of a sheet irrespective of a differential conveyance distance. The paper feed apparatus is provided with a first large volume paper feed apparatus 100A having a control unit 130 which performs first correction control to correct the skew of a sheet by controlling a first conveyance unit 110 and forming a loop of the sheet P before a paper stop rollers 110d, and also performs second correction control to correct the skew of a sheet by controlling a second conveyance unit 120 and forming a loop of the sheet before a paper stop rollers 110d. In this case, the control unit 130 controls the first conveyance unit 110 and the second conveyance unit 120 in order that the skew correcting ability of the second correction control becomes greater than the skew correcting ability of the first correction control.
Abstract:
A driving device includes: a first motor that transmits power to a rotation shaft of a conveyance roller for conveying a paper sheet; a second motor that transmits power to the rotation shaft of the conveyance roller; and a motor controller that controls rotational speeds of the first and second motors by changing a control value, wherein the motor controller controls the control value of the first motor at multiple steps at a time of acceleration or deceleration and changes the control value of the second motor according to a change range of the control value of the first motor in synchronization with a timing when the control value of the first motor is changed.
Abstract:
A fixing apparatus includes an upper pressure roller, a fixing belt, a lower pressure roller which cooperates with the upper pressure roller and the fixing belt for forming a fixing nip portion which holds and conveys a sheet with a toner image therebetween; a drive motor which rotates the lower pressure roller; a plurality of motors each of which is capable of generating a braking force in the direction to hinder rotation of the upper pressure roller and an assist force in the direction to assist rotation of the upper pressure roller; a torque generation unit which generate an effective braking force in the direction to hinder rotation of the fixing side member as a combination of the braking and assist forces; and a control unit which switches the motor used to generate the braking force among the plurality of motors in accordance with a predetermined condition.
Abstract:
A control device includes a controller that determines, based on physical property information corresponding to physical property of a recording sheet and read information on an image evaluated as abnormal through reading of an image on the recording sheet by a reading section on a recording sheet conveyance path, a process condition under which an image forming section performs image forming on the recording sheet.
Abstract:
An image forming apparatus performs a serviceman call detection mode during its idling time. In this time, a control portion controls upper and lower pressuring rollers to be clamped, controls a driving motor, and controls a change-over mechanism to switch a braking motor off. A torque detection portion detects a torque value Y of the driving motor at this time. The control portion then controls the upper and lower pressuring rollers to be clamped, controls the driving motor, and controls the change-over mechanism to switch the braking motor on. The torque detection portion detects a torque value Z of the driving motor at this time. The control portion subtracts the torque value Y from the torque value Z to calculate a difference value. The control portion determines that the braking motor is broken down when the difference value does not exceed the threshold value.
Abstract:
A motor drive apparatus drives and controls a plurality of motors that rotate a common drive shaft. The motor drive apparatus includes a motor drive hardware processor that outputs equal drive power to each of the plurality of motors, and manipulates the drive power with a rotational speed detection signal of any one of the plurality of motors as a feedback signal. The feedback signal is switched based on conditions such as responsiveness and efficiency.
Abstract:
An image forming system includes: an image forming apparatus that forms an image on a sheet; one or more sheet carrying devices successively disposed on the downstream side of the image forming apparatus; and a control device that controls the image forming apparatus and the one or more sheet carrying devices based on a job that designates a page configuration containing a page order and sheet types, wherein the sheet carrying device includes a bypass conveyance path along which the sheet output from an upstream device is conveyed toward a downstream device, and a sheet tray unit that temporarily stores the sheet output from the upstream device and discharges the sheet toward the bypass conveyance path, and the control device divides the job into sheet types and determines a printing order of the divided sheet types and sheet types to be stored in the sheet carrying device.
Abstract:
An image forming apparatus comprises a drive motor configured to rotate the lower pressure roller, a torque generation unit for generating a braking force in the direction to hinder rotation of a fixing belt in order to adjust the differential speed between the surface speed of the fixing belt and the surface speed of the lower pressure roller, and a control unit for adjusting the braking force generated by the torque generation unit. The control unit adjusts the braking force generated by the torque generation unit to decrease if the rotational torque of the drive motor is larger than a predetermined target torque, and increase if the rotational torque of the drive motor is smaller than the predetermined target torque.