Abstract: A photodetector including: a case including a light receiving surface provided on an upper surface and having a first region that transmits visible light and a second region that transmits less visible light than the first region; a printed circuit board provided to face the light receiving surface; and a plurality of electronic components provided on a light receiving surface side of the printed circuit board and including a first light receiving element configured to detect visible light. The first light receiving element is disposed at a first position of the printed circuit board exposed to the visible light transmitted through the first region. The number of mounted electronic components disposed at the first position is smaller than the number of mounted electronic components disposed at a second position of the printed circuit board other than the first position.

Abstract: An inkjet recorder includes: a drum that is rotatable about a rotation axis and conveys a recording medium; a head unit including an ejection surface that ejects ink that forms an image on the medium conveyed to the drum, the head unit being movable between a recording position at which the ejection surface faces the drum and a cleaning position separated from the recording position in a direction parallel to the rotation axis; and a cleaning unit that is disposed at a position being adjacent to the drum in the direction parallel to the rotation axis and facing the ejection surface of the head unit located at the cleaning position, and cleans the ejection surface, wherein the head unit includes heads having the ejection surface, the cleaning unit includes a cleaning member, the cleaning member has a cleaning surface, and the cleaning surface cleans the ejection surface.

Abstract: A photodetector includes: an upper case including a light receiving portion on an upper surface and a side portion extending downward from the light receiving portion; a printed circuit board facing the light receiving portion; and a lower case including a support portion configured to support the printed circuit board, an opening on one side surface and configured to allow a connector to be inserted therethrough, and a hook on another side surface. The lower case is fitted to the upper case such that at least the printed circuit board and the support portion are surrounded. The upper case has a cut portion configured to prevent interference with the hook when being attached. At least part of the side portion adjacent to the cut portion and on a side of the opening extends up to a lower side of the opening.

Abstract: A photodetector including: a case including a light receiving surface provided on an upper surface and having a first region that transmits visible light and a second region that transmits less visible light than the first region; a printed circuit board provided to face the light receiving surface; and a plurality of electronic components provided on a light receiving surface side of the printed circuit board and including a first light receiving element configured to detect visible light. The first light receiving element is disposed at a first position of the printed circuit board exposed to the visible light transmitted through the first region. The number of mounted electronic components disposed at the first position is smaller than the number of mounted electronic components disposed at a second position of the printed circuit board other than the first position.

Abstract: An image forming apparatus that forms an image on a sheet includes: a rotating body that forms the image; a motor that rotationally drives the rotating body; a current measurer that measures a motor current flowing through a current supply path including a winding of the motor at a measurement timing that is a timing after the motor is started; a torque acquisitor that acquires a torque value of the motor, based on a measured value of the motor current; and a corrector that performs correction to cancel a current change amount based on a characteristic change depending on a temperature state of the motor at the measurement timing, in acquisition of the torque value by the torque acquisitor.

Abstract: An image forming apparatus that forms an image on a sheet includes: a rotating body that forms the image; a motor that rotationally drives the rotating body; a current measurer that measures a motor current flowing through a current supply path including a winding of the motor at a measurement timing that is a timing after the motor is started; a torque acquisitor that acquires a torque value of the motor, based on a measured value of the motor current; and a corrector that performs correction to cancel a current change amount based on a characteristic change depending on a temperature state of the motor at the measurement timing, in acquisition of the torque value by the torque acquisitor.

Abstract: A power control apparatus that supplies an AC current to a load and adjusts a current amount by setting a portion of a phase range among each of half-wave periods of the AC current to be supplied as a conduction angle and setting the remainder as a non-conduction angle, includes: a reference value determiner that defines a period across a plurality of half-wave periods as a current determination period and that determines a reference value of the conduction angle; and a distribution processor that determines a distribution value to distribute the conduction angle and performs current amount adjustment by distributed conduction angles, wherein the distribution processor determines the distribution value within one current determination period such that the value includes a positive distribution value and a negative distribution value, and an average value of the distributed conduction angles is within ±2.5% with respect to the reference value.

Abstract: An image forming apparatus that conveys a sheet and forms an image on the sheet, the image forming apparatus includes: a plurality of rollers that are arranged at different positions from one another in a conveyance path of the sheet, and convey the sheet; a motor that rotationally drives at least one of the rollers; a drive that drives the motor by applying a current to the motor; and a hardware processor that determines whether a jam has occurred and a jam type, in accordance with a change in the current flowing in the motor in a period during which the sheet is expected to pass through a target roller being rotationally driven by the motor among the rollers.

Abstract: An image forming apparatus that transfers an image from an image carrier onto a sheet passing between the image carrier rotating and a transfer member includes a fixing unit configured to thermally fix the image on the sheet while nipping and conveying the sheet with a pair of fixing members after the transfer, at least one of the fixing members rotating; a measuring unit configured to measure surface movement speed of the sheet in a non-contact manner while the sheet is being conveyed by the fixing members; and a control unit configured to control rotation speed of the fixing members in accordance with a result of the measurement, to adjust speed of conveyance of the sheet to a target speed determined beforehand for peripheral speed of the image carrier, the control being performed while the sheet being conveyed is in contact with the transfer member and the fixing members.

Abstract: A power control apparatus that supplies an AC current to a load and adjusts a current amount by setting a portion of a phase range among each of half-wave periods of the AC current to be supplied as a conduction angle and setting the remainder as a non-conduction angle, includes: a reference value determiner that defines a period across a plurality of half-wave periods as a current determination period and that determines a reference value of the conduction angle; and a distribution processor that determines a distribution value to distribute the conduction angle and performs current amount adjustment by distributed conduction angles, wherein the distribution processor determines the distribution value within one current determination period such that the value includes a positive distribution value and a negative distribution value, and an average value of the distributed conduction angles is within ±2.5% with respect to the reference value.

Abstract: An image reading apparatus includes: three or more light sources configured to each emit light; a light receiving unit including a common light receiving surface configured to detect each light emitted; and an image generation unit configured to cause the three or more light sources to be switched over in a predetermined order and emit the corresponding light, and generate an image read from a document, wherein at least one of the three or more light sources includes a white light source and an optical filter, and the optical filter is configured such that a half-value width of a wavelength with respect to a maximum intensity of a spectral characteristic of the emitted light after transmission is wider than a half-value width of a wavelength with respect to a maximum intensity of the spectral characteristic of the light emitted from at least one of the other light sources.

Abstract: An image reading apparatus includes: three or more light sources configured to each emit light; a light receiving unit including a common light receiving surface configured to detect each light emitted; and an image generation unit configured to cause the three or more light sources to be switched over in a predetermined order and emit the corresponding light, and generate an image read from a document, wherein at least one of the three or more light sources includes a white light source and an optical filter, and the optical filter is configured such that a half-value width of a wavelength with respect to a maximum intensity of a spectral characteristic of the emitted light after transmission is wider than a half-value width of a wavelength with respect to a maximum intensity of the spectral characteristic of the light emitted from at least one of the other light sources.

Abstract: An image forming apparatus that transfers an image from an image carrier onto a sheet passing between the image carrier rotating and a transfer member includes a fixing unit configured to thermally fix the image on the sheet while nipping and conveying the sheet with a pair of fixing members after the transfer, at least one of the fixing members rotating; a measuring unit configured to measure surface movement speed of the sheet in a non-contact manner while the sheet is being conveyed by the fixing members; and a control unit configured to control rotation speed of the fixing members in accordance with a result of the measurement, to adjust speed of conveyance of the sheet to a target speed determined beforehand for peripheral speed of the image carrier, the control being performed while the sheet being conveyed is in contact with the transfer member and the fixing members.

Abstract: An image forming apparatus includes: a sheet feeding unit configured to feed a plurality of sheets to an image forming unit one by one; the image forming unit configured to form a toner image based on image data; a fixing unit configured to fix the toner image formed on each sheet by the image forming unit with a fixing member, the fixing unit including the fixing member configured to be brought into contact with each sheet supplied from the image forming unit and heat each sheet; a measuring unit configured to measure a temperature of the fixing member; and a control unit configured to instruct the fixing unit to start and stop a temperature increasing operation, and provide the image data to the image forming unit, wherein the control unit includes: a temperature drop rate calculating unit; a temperature rise rate predicting unit; and an instructing unit.

Abstract: An image forming apparatus includes an image forming section to form a toner image and transfer the toner image to a recording medium and a fixing section to heat the recording medium transferred with the toner image and further an image analyzing section to extract a density value or a size value of an imaging object included in an image, and a temperature determining section to determine a minimum fixing temperature based on the density value or size value of the imaging object included in a page image. The temperature determining section determines the minimum fixing temperature to be lower when a highest one of the density values is lower than when the highest value is higher or determines the minimum fixing temperature to be lower when a largest one of the size values is smaller than when the largest size value is larger.

Abstract: An image forming apparatus forming toner images sequentially on recording sheets transported at intervals, and thermally fixing the toner images by passing the recording sheets through a fixing position on a heating roller. The target fixing temperature is determined according to information of an image on each page. When a first fixing temperature for a given page is higher than a second fixing temperature for the succeeding page and the difference therebetween is greater than a predefined value, part or all of a first period, during which the thermal fixing operation for the given page is performed, and a second period, which corresponds to an interval between the two pages, are reserved for raising the surface temperature by the difference, and temperature control is performed during the reserved periods such that the surface temperature reaches the second temperature before the thermal fixing operation for the succeeding page starts.

Abstract: An image forming apparatus includes: a sheet feeding unit configured to feed a plurality of sheets to an image forming unit one by one; the image forming unit configured to form a toner image based on image data; a fixing unit configured to fix the toner image formed on each sheet by the image forming unit with a fixing member, the fixing unit including the fixing member configured to be brought into contact with each sheet supplied from the image forming unit and heat each sheet; a measuring unit configured to measure a temperature of the fixing member; and a control unit configured to instruct the fixing unit to start and stop a temperature increasing operation, and provide the image data to the image forming unit, wherein the control unit includes: a temperature drop rate calculating unit; a temperature rise rate predicting unit; and an instructing unit.

Abstract: An image forming apparatus includes an image forming section to form a toner image and transfer the toner image to a recording medium and a fixing section to heat the recording medium transferred with the toner image and further an image analyzing section to extract a density value or a size value of an imaging object included in an image, and a temperature determining section to determine a minimum fixing temperature based on the density value or size value of the imaging object included in a page image. The temperature determining section determines the minimum fixing temperature to be lower when a highest one of the density values is lower than when the highest value is higher or determines the minimum fixing temperature to be lower when a largest one of the size values is smaller than when the largest size value is larger.

Abstract: An image forming apparatus forming toner images sequentially on recording sheets transported at intervals, and thermally fixing the toner images by passing the recording sheets through a fixing position on a heating roller. The target fixing temperature is determined according to information of an image on each page. When a first fixing temperature for a given page is higher than a second fixing temperature for the succeeding page and the difference therebetween is greater than a predefined value, part or all of a first period, during which the thermal fixing operation for the given page is performed, and a second period, which corresponds to an interval between the two pages, are reserved for raising the surface temperature by the difference, and temperature control is performed during the reserved periods such that the surface temperature reaches the second temperature before the thermal fixing operation for the succeeding page starts.

Abstract: A load drive device has a load drive unit including an input system electrically connectable to a control power supply and an output system electrically connectable to a load drive power supply. The load drive unit supplies the electrical load with load drive voltage from the load drive power supply via the output system when the control power supply applies control voltage to the input system. A potential difference detection unit detects a potential difference between the control voltage and the load drive voltage. A potential fixing unit fixes a potential at a control system electrical route, connecting the control power supply and the input system of the load drive unit, to a prohibition level that prohibits the output system of the load drive unit from driving the electrical load when the potential difference detected by the potential difference detection unit exceeds a predetermined threshold value.