Patent application number | Description | Published |
20100158551 | IMAGE-FORMING APPARATUS - An image-forming apparatus includes an image-bearing member configured to bear an image, a transfer belt to which the image on the image-bearing member is transferred and configured to transfer the image onto a sheet, a first drive unit configured to drive the image-bearing member to rotate, a second drive unit configured to drive the transfer belt to rotate via a speed reduction member interposed therebetween, a detection unit configured to detect a circumferential speed of the transfer belt, and a control unit configured to control the first drive unit in accordance with the circumferential speed of the transfer belt detected by the detection unit. | 06-24-2010 |
20100220982 | MOTOR CONTROL APPARATUS AND IMAGE FORMING APPARATUS - A motor control apparatus for controlling a DC motor includes a detection unit configured to detect an angular speed of the DC motor, and a control unit configured to, when the DC motor is accelerated, increase a control value that controls a driving of the DC motor at a constant rate from a first control value corresponding to an angular speed lower than a target angular speed up to a second control value corresponding to an angular speed higher than the target angular speed, and switch the control value that controls the driving of the DC motor to a control value corresponding to the target angular speed in response to the detection result of the detection unit reaching the target angular speed. | 09-02-2010 |
20100303513 | IMAGE FORMING APPARATUS - An image forming apparatus includes a rotatable belt member; a stretching roller for stretching the belt member; a plurality of line-like marks which are arranged in a rotational direction of the belt member and are formed stepwisely on a surface of the belt member; the marks being tilted from a rotational axis direction of the belt member at least at end portions thereof on sides close to an end surface of the belt member; and control means for controlling rotation of the belt member on the basis of a result of detection of the marks. | 12-02-2010 |
20100327797 | MOTOR CONTROL APPARATUS AND IMAGE FORMING APPARATUS - A motor control apparatus for controlling a DC motor includes a first detection unit configured to detect an angular velocity of the DC motor, a driven member configured to be driven by the DC motor, a control unit configured to perform, during start-up of the DC motor, feed forward control for changing a control value used for controlling drive of the DC motor from a first control value corresponding to an angular velocity smaller than a target angular velocity to a second control value corresponding to the target angular velocity, and to change the feed forward control to feedback control for controlling the control value based on a detection result by the first detection unit to keep the DC motor at the target angular velocity, and a second detection unit configured to detect whether the driven member has been replaced. | 12-30-2010 |
20100329724 | MOTOR CONTROL APPARATUS AND IMAGE FORMING APPARATUS - A motor control apparatus that controls a DC motor includes a detection unit configured to detect angular speed of the DC motor, a driven member configured to be driven by the DC motor, and a control unit configured to increase, when starting to drive the DC motor, a control value for controlling driving of the DC motor from a first control value to a second control value at a predetermined increase rate, wherein the control unit detects a start-up characteristic of the DC motor based on a detection result of the detection unit, and corrects the first control value or the increase rate according to a result of comparing a detected start-up characteristic and a predetermined start-up characteristic such that the start-up characteristic of the DC motor becomes closer to the predetermined start-up characteristic. | 12-30-2010 |
20110026969 | IMAGE FORMING APPARATUS - A control unit sets a first feedback gain for suppressing an angular speed variation of a first frequency, which causes a misalignment of images to be overlaid with each other, to the first nd feedback unit in a first image forming mode in which images formed on the first and the second image carriers are overlaid, and sets a second feedback gain for suppressing an angular speed variation of a second frequency, which causes a periodic uneven density on an image that is to be formed with a uniform density, to the first feedback unit in a second image forming mode in which an image is formed using the first image carrier. | 02-03-2011 |
20130084104 | IMAGE FORMING APPARATUS - A control unit sets a first feedback gain for suppressing an angular speed variation of a first frequency, which causes a misalignment of images to be overlaid with each other, to the first and feedback unit in a first image forming mode in which images formed on the first and the second image carriers are overlaid, and sets a second feedback gain for suppressing an angular speed variation of a second frequency, which causes a periodic uneven density on an image that is to be formed with a uniform density, to the first feedback unit in a second image forming mode in which an image is formed using the first image carrier. | 04-04-2013 |
20130216261 | ROTARY DRIVING APPARATUS, CONTROL METHOD THEREFOR, STORAGE MEDIUM STORING CONTROL PROGRAM THEREFOR, AND IMAGE FORMING APPARATUS - A rotary driving apparatus that is capable of controlling a rotational speed correctly even when an anomaly occurs. A drive unit rotates a rotating member. A rotating body is rotated with the rotating member. A detection unit detects scales formed on the rotating body. A calculation unit calculates rotation information about the rotating member based on the detection result by the detection unit. A control value setting unit sets a control value to a predetermined value when the rotation information falls outside a predetermined range and a count of determinations that the rotation information falls outside the predetermined range is smaller than a predetermined count, and sets the control value based on the rotation information when the rotation information falls outside the predetermined range and the count of determinations is larger than the predetermined count. A control unit controls the drive unit based on the set control value. | 08-22-2013 |
20130322898 | POWER SUPPLY APPARATUS FOR SAFETY LOAD SHUTDOWN AND IMAGE FORMING APPARATUS INCLUDING THE SAME - When a detection signal indicates that a switch has switched off, a first relay cuts off the supply of alternating current from a commercial alternating-current source to a third DC power source and terminates a first load such as a motor and a high-voltage power source. When the detection signal indicates that the switch has switched off, a control circuit executes shutdown processing for safely terminating an operation of a second load such as a hard disk drive. When the shutdown processing is complete, the control circuit outputs a signal for terminating an operation of a second DC power source. When the shutdown signal is input, a second relay terminates the operation of the second load by cutting off the supply of the alternating current from the commercial alternating-current source to a second DC power source. | 12-05-2013 |