摘要:
A recording media smoothness detector includes a sensor and a calculator. The sensor includes a light source to emit light toward a recording medium and a light detector to detect an amount of light reflected by the recording medium. The calculator includes a first memory to store an initial output value of the sensor and a second memory to store a decreased output percentage of the sensor relative to the initial output value per number of recording media detected. The calculator is configured to calculate a decreased output amount of the sensor from the decreased output percentage of the sensor per number of recording media detected, according to a number of recording media detected by the sensor, to adjust a luminosity of the light source based on the calculated decreased output amount of the sensor and determine a type of the recording medium based on an output of the sensor after the adjustment of the luminosity of the light source and based on the number of recording media detected by the sensor.
摘要:
An image forming apparatus includes a storage to store recording media, a smoothness detector to detect smoothness of the recording media, a memory unit to store smoothness values detected by the smoothness detector, a transfer device to transfer a toner image onto the recording media, a fixing device to fix the toner image onto the recording media, a temperature controller to determine a target fixing temperature for a second and subsequent recording media based on a predicted value calculated from the smoothness values, and a processor to reset the smoothness values in response to detection of an external factor that causes the smoothness detector to provide a smoothness value out of a predetermined range of the predicted value during an image forming operation from when the processor receives a sheet-feeding permission signal of one of the recording media stored in the storage until the recording medium is ejected.
摘要:
An image forming apparatus includes paper trays to contain and feed a recording sheet on which a toner image is transferred; status sensors to detect a storage status of the recording sheet contained in the paper trays; a sheet sensor to detect a smoothness of the recording sheet; a memory to store detection values of the smoothness detected by the sheet sensor; a fixing device to heat and press the toner image transferred onto the recording sheet and fix it onto the recording sheet; and a control circuit to determine a target fixing temperature of the fixing device based on the detection values stored in the memory. The control circuit determines the target fixing temperature for successive recording sheets depending on the detected smoothness, and resets the detection values stored in the memory to zero when the status sensors detect a change in the storage status of the paper trays.
摘要:
An image forming apparatus includes paper trays to contain and feed a recording sheet on which a toner image is transferred; status sensors to detect a storage status of the recording sheet contained in the paper trays; a sheet sensor to detect a smoothness of the recording sheet; a memory to store detection values of the smoothness detected by the sheet sensor; a fixing device to heat and press the toner image transferred onto the recording sheet and fix it onto the recording sheet; and a control circuit to determine a target fixing temperature of the fixing device based on the detection values stored in the memory. The control circuit determines the target fixing temperature for successive recording sheets depending on the detected smoothness, and resets the detection values stored in the memory to zero when the status sensors detect a change in the storage status of the paper trays.
摘要:
A fixing device includes a rotatable fuser member a heater, a rotatable pressure member, a thermometer, and a feedback controller. The rotatable fuser member is subjected to heating. The heater heats the fuser member to a heating temperature. The rotatable pressure member is disposed opposite the fuser member. The fuser member and the pressure member are pressed against each other to form a fixing nip therebetween, through which the recording medium is conveyed, so as to fix the toner image in place under heat and pressure. The thermometer is disposed adjacent to the pressure member to detect an operational temperature of the pressure member. The feedback controller is operatively connected with the thermometer to control the heating temperature according to the detected operational temperature, so that the recording medium exhibits a substantially constant post-fixing temperature downstream from the fixing nip regardless of the heat capacity of the recording medium.
摘要:
A fixing device includes a fixing rotary body, an opposed member opposing the fixing rotary body to form a nipping portion, and a heater to heat the fixing rotary body. The heater includes heat generators arranged in a width direction of a recording medium and separately supplied with power. When an unfixed image on the medium has an image area and a non-image area, power supplied to each of the heat generators is controlled so that, of the heat generators, a first heat generator corresponding to the image area becomes a higher temperature and second heat generators corresponding to the non-image area becomes a lower temperature. When the second heat generators are adjacent to each other, power supplied to one of the second heat generators closer to the image area is set to be greater than power supplied to another of the second heat generators farther from the image area.
摘要:
A fixing device includes a rotatable fixing member to rotate while contacting an unfixed image; a pressure member to form a fixing nip with the fixing member; a heating member having a plurality of heating elements divided in a direction perpendicular to a conveyance direction of a sheet; a heat performance sensor to detect heating performance of each heating element of the heating member, and a controller to control the heating member. The controller controls each heating element independently such that a temperature of a portion of the fixing member corresponding to a blank area becomes lower than the temperature of a portion of the fixing member corresponding to an image area; and controls the temperature to be maintained at each heating element based on the detection result of the heating performance of each heating element detected by the heat performance sensor.
摘要:
A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, a temperature detector, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The pressure member presses against the fuser member to form a fixing nip therebetween. The heater is disposed adjacent to the fuser member to heat the fuser member. The temperature detector is directed to at least one of the fuser member, the pressure member, and the heater to detect an operational temperature of the fixing device. The controller is operatively connected to the temperature detector and the heater to control power supply to the heater according to readings of the temperature detector, so as to regulate the detected operational temperature at a setpoint temperature that is variable depending on a print page printed on the recording medium.
摘要:
A temperature control method of calculating a temperature of a recording medium after fixing and used in a thermal fixing device includes separating calculations of calculating the temperature of the recording medium after fixing into first-stage calculations to be performed before start of printing and second-stage calculations to be performed in real time during the printing, performing the first-stage calculations, and performing the second-stage calculations to calculate a result of the temperature of the recording medium after fixing. Further, the result of the temperature of the recording medium after fixing is used to control obtaining a desired temperature of the recording medium after fixing, and the temperature of the recording medium after fixing is calculated without directly measuring the temperature of the recording medium after fixing.
摘要:
An image forming apparatus includes an image forming device to form a toner image on a recording medium under a prescribed image forming condition, a fixing device to fix the toner image borne on the recording medium thereonto by heating the recording medium based on target fixing temperature, and a detector to detect a type of recording medium. The type is used in setting at least one of the image forming condition and the target fixing temperature. The inequality Tb>Ta is established when Ta represents a time period needed to reach a setting of fixing temperature allocated to the recording medium with its tip detected by the detector after detection of the tip and Tb represents a time period needed for the recording medium with its tip detected by the detector to reach the fixing device after detection of the tip.