Patent application number | Description | Published |
20110299899 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A fixing device includes a fixing rotary body inside which a heat generator is disposed and an exciting coil unit disposed opposite the heat generator via the fixing rotary body. A first moving mechanism is connected to one of the heat generator and the exciting coil unit to move the one of the heat generator and the exciting coil unit between a first position where the exciting coil unit is disposed away from the heat generator and a second position where the exciting coil unit is disposed closer to the heat generator. The exciting coil unit heats a first heat generation layer of the fixing rotary body at the first position, and heats both the first heat generation layer of the fixing rotary body and a second heat generation layer of the heat generator at the second position. | 12-08-2011 |
20120093532 | FIXING DEVICE, FIXING DEVICE CONTROL METHOD, AND IMAGE FORMING APPARATUS - A fixing device includes a rotatable fuser member, a rotatable pressure member, a heater, a rotary driver, a thermometer, and a controller. The rotatable fuser member is subjected to heating. The rotatable pressure member is disposed opposite the fuser member. The heater heats the fuser member. The rotary driver imparts torque to at least one of the fuser and pressure members. The fuser member and the pressure member are pressed against each other to form a fixing nip therebetween. The thermometer is disposed external to the fixing nip to detect a temperature outside the fixing nip. The controller is operatively connected with the thermometer to control an amount of heat applied to the recording medium through the fixing nip according to the detected temperature, so that the recording medium exhibits a substantially constant post-fixing temperature downstream from the fixing nip. | 04-19-2012 |
20120093534 | FIXING DEVICE, FIXING DEVICE CONTROL METHOD, AND IMAGE FORMING APPARATUS - 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. | 04-19-2012 |
20120148287 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A fixing device includes a first alternating electric current power supply that outputs a first alternating electric current having a first frequency that causes a magnetic flux generated by an exciting coil to reach a first heat generation layer of a fixing rotary body; a second alternating electric current power supply that outputs a second alternating electric current having a second frequency that is lower than the first frequency and causes the magnetic flux to reach the first heat generation layer of the fixing rotary body and a second heat generation layer of a heat generator; and a switch circuit connected to the exciting coil, the first alternating electric current power supply, and the second alternating electric current power supply to selectively connect the first alternating electric current power supply or the second alternating electric current power supply to the exciting coil. | 06-14-2012 |
20120148317 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A fixing device includes a switch circuit that selectively connects an alternating electric current power supply to a first exciting coil and a second exciting coil. When the switch circuit connects the alternating electric current power supply to both the first exciting coil and the second exciting coil, the first exciting coil and the second exciting coil together generate a first magnetic flux having a first density that reaches only a first heat generation layer of a fixing rotary body. When the switch circuit connects the alternating electric current power supply to the first exciting coil only, the first exciting coil generates a second magnetic flux having a second density greater than the first density that reaches both the first heat generation layer of the fixing rotary body and a second heat generation layer of a heat generator. | 06-14-2012 |
20120243895 | TEMPERATURE CONTROL METHOD OF THERMAL FIXING DEVICE, THERMAL FIXING DEVICE, AND IMAGE FORMING APPARATUS - 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. | 09-27-2012 |
20130308990 | FIXING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A fixing device includes an endless belt formed into a loop and rotatable in a given direction of rotation. An opposed rotary body contacts the endless belt to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater is disposed in proximity to an irradiation span spanning on an inner circumferential surface of the endless belt in a circumferential direction thereof to emit light that irradiates and heats the irradiation span of the endless belt. A shield is interposed between the heater and the irradiation span of the endless belt in a diametrical direction thereof to shield the irradiation span of the endless belt from heated air surrounding the heater. | 11-21-2013 |