Abstract: An image forming apparatus is provided in which a toner image is fixed onto a recording medium with use of a fixer fluid in liquid form without causing generation of curls and wrinkles in the recording medium, the amount of the fixer fluid to be used can be reduced, even a multi-color toner image can be fixed in a short period of time, and power consumption is small. The image forming apparatus includes a toner image forming section, an intermediate transfer section, a secondary transfer section, a fixing section, and a recording medium supply section. A fixer fluid applying section included in the fixing section applies a fixer fluid to an image portion and a non-image portion of a recording medium. The quantity of applying the fixer fluid for a non-image portion is smaller than that for a image portion.

Abstract: An image heating device is operational to estimate a temperature of a pressure roller so as to determine a set temperature for a roller belt in a subsequent image heating period.

Abstract: A fixing unit is provided with a fixing belt that heats recording paper that bears and moves a toner image, an exciting coil that generates magnetic flux in the fixing belt and causes the fixing belt to produce heat by electromagnetic induction, and a heat production adjustment section that adjusts the calorific value distribution of the fixing belt by adjusting the magnetic flux acting upon the fixing belt.

Abstract: A chip-like printed antenna in which an open end is formed by at least two antenna conductors separated from each other is mounted on a printed-circuit board. A ground required by one or plural other modules is disposed and mounted on the printed-circuit board so as to surround a remaining area of a surrounding area of the printed antenna except a partial area as indicated by oblique line parts. By this, in the printed-circuit board , a radiation electric field does not come to have a dipole mode, but is formed into a balloon shape and is radiated in one direction as indicated by a broken line.

Abstract: A heat-fixing apparatus is provided that enables a rise in temperature of a heating member to be closely tracked, and an excessive rise in temperature of the heating member to be obviated, a simple configuration and irrespective of differences in the operating mode, such as immediately after a rise in temperature or during continuous operation. Different threshold values are set in accordance with different modes, such as a warm-up mode and a fixing operation mode. Threshold decisions on a switching frequency controlled by a frequency control section are made using different threshold values, according to the mode. A switching frequency of switching elements are varied so that power necessary in each mode is supplied to an exciting coil. An excessive rise in temperature is prevented in each mode by halting a switching element drive in accordance with the threshold decision.

Abstract: An image heating device is provided with reduced cost, by which a difference in glossiness among printed images on recording media is eliminated, and the wrapping of a belt and the like at a high temperature is prevented. In the image heating device, controlling means estimates a temperature of a pressure roller according to at least one of a temperature of a belt detected by a temperature sensor and a variation with time in the detected temperature from completion of the heating after application of an electric power to the magnetization coil by an exciting circuit is stopped and the heating of the belt by the heating roller is stopped, so as to determine a set temperature for the belt in a subsequent image heating period.

Abstract: An image heating device is provided with reduced cost, by which a difference in glossiness among printed images on recording media is eliminated, and the wrapping of a belt and the like at a high temperature is prevented. In the image heating device, a controller estimates a temperature of a pressure roller according to at least one of a temperature of a belt detected by a temperature sensor and a variation with time in the detected temperature from completion of the heating after application of an electric power to the magnetization coil by an exciting circuit is stopped and the heating of the belt by the heating roller is stopped, so as to determine a set temperature for the belt in a subsequent image heating period.

Abstract: A temperature determining device is composed of a temperature detecting unit that detects a temperature of a determination object member based on an intensity of infrared rays from the object member, a unit for determining a temperature for correction that determines a temperature of an opposing member opposed to the object member or a temperature of a member whose temperature changes in correlation to a change in the temperature of the opposing member, and a calculating unit that corrects the detected temperature obtained by the temperature detecting unit using the temperature as the temperature for correction obtained by the unit for determining a temperature for correction. Thus, stable temperature determination can be performed accurately without being influenced by infrared rays from around a determination object member.

Abstract: A developing device includes an endless belt stretched around a plurality of support members, a portion of a peripheral surface of the endless belt contacting a portion of a surface of an image carrying member at a contact region, the endless belt being rotated by a driving force transmitted from a driving device at a driving transmission position, and a layer regulating member pressed against a portion of the endless belt at a pressure contact region positioned upstream, with respect to the endless belt's rotation direction, from the contact region. Further provided is a load device applying, to at least a portion of the endless belt between the pressure contact region and the contact region, which is positioned upstream, with respect to the endless belt's rotation direction, from the driving transmission position, a load acting in a direction opposite to the rotation direction of the endless belt.

Abstract: In a fixing unit 230, a medium introducing port 250 is provided near a gripping part 230a of a housing 230, and a sheet material 90 to be subjected to a fixing process is guided to the medium introducing port. A shutter 260 is provided slanted at a given angle with respect to a gripping surface 240 of the gripping part 230a of the fixing unit 230 such that the shutter has a fulcrum at a part thereof, which is closer to the gripping part 230a of the fixing unit 230, at the medium introducing port 250, and the shutter 260 is turnable to a position to close the medium introducing port 250 while resisting the urging forces of the twisted springs 270.

Abstract: A PDA includes a printed-circuit board on which at least one printed antenna pair having two chip-like printed antennas, which receive linearly polarized signals and are disposed along axes orthogonal to each other, is mounted. In each of the printed antennas, an open end is formed of at least two antenna conductors separated from each other. Besides, in the printed-circuit board, a ground required by one or plural other modules is disposed so as to surround a surrounding area of at least three sides of four sides forming a rectangular section in each of the printed antennas, and each of the printed antennas is disposed and mounted so that a remaining one side faces an edge portion of the printed-circuit board. While the PDA can receive circularly polarized signals very effectively, the degree of freedom in layout is greatly expanded and miniaturization can be realized.

Abstract: A fixing device as an image heating device is provided, by which a difference in glossiness is not caused in a recording medium in the axial direction of a pressure roller. When a print request is issued during the end-processing sequence, an electric power applied to a magnetization coil via an exciting circuit is dropped to 0 by controlling means during the start-processing sequence, and after an appropriate interval, the heating with full power is restarted by the controlling means. By so doing, the decrease in temperature at both ends of a fixing belt and a heat-generating roller in the axial direction can be compensated.

Abstract: A fixing device is formed by using a heat generating roller having magnetism and electric conductive characteristics and a magnetizing coil opposed to the outer peripheral of the heat generating roller and generating heat on the heat generating roller by an electromagnetic induction. The magnetizing coil is formed in such a manner that 60 copper wires whose surfaces are insulated and have the outside diameter of 0.2 mm are bundled to form a bundle of wires and the bundle of wires is drawn in the direction of rotation axis of the heat generating roller and wound in the direction of a circumference of the heat generating roller. Further, the magnetizing coil is disposed so that the bundles of wires mutually come into close contact along the circumference of the heat generating roller to cover the upper half of the heat generating roller.

Abstract: A heating device utilizing electromagnetic induction is provided with an induction heating unit that is opposed to a heating member and causes the heating member to heat through electromagnetic induction. The induction heating unit has an exciting coil for generating a magnetic field and a coil guide member on which the exciting coil is wound. The exciting coil is formed in at least two layers in such a manner that a first layer is formed on a circumferential surface of the coil guide member by winding a plurality of turns and a second layer is formed around and outside the first layer on the side opposite to the coil guide member, and winding of each of the second layer and following layers is started from a position close to a winding start position of the first layer.

Abstract: An image heating device includes a heat generating member that heats a body to be heated that is allowed to travel while carrying an image, an excitation unit that is provided close to the heat generating member and generates magnetic flux so as to cause the heat generating member to generate heat by electromagnetic induction, and a heat generation suppressing unit that suppresses an amount of heat generated in the heat generating member by regulating magnetic flux generated by the excitation unit. The heat generation suppressing unit suppresses heat generation of the heat generating member in a region corresponding to a region including at least a center portion of the body to be heated in a width direction. Thus, an amount of heat generated in the width direction can be regulated using a simple configuration at a reduced cost. Further, when the heat generation suppressing unit is operated, diffusion of magnetic flux into a wide area can be prevented.

Abstract: A release layer, which contains fluoropolymers is applied on a die surface of a shaping die, and is baked. An elastic layer is applied onto the external surface of the release layer and is baked. A supporting layer containing heat-resistant synthetic resin is applied onto the external surface of the elastic layer, and is dried. The dried supporting layer is polished to remove the unevenness, and the supporting layer is baked. The release layer, the elastic layer and the supporting layer are turned inside out to be removed from the die surface. The evenness of the fixing belt is improved, and the pressure unevenness is reduced.

Abstract: A short ring is provided outside a support frame. In the short ring, eddy current is generated in such a direction as to cancel apart of a magnetic flux developed from the exciting coil when it is fed with current, which the part of the magnetic flux leaks to outside. When the eddy current is generated, a magnetic field is developed in such a direction as to cancel the magnetic field by the leaking flux, as taught by Fleming's law. The result is that unnecessary radiation by the leaking flux is prevented, and hence noise generation in other members or devices is suppressed.

Abstract: An image heating device with a small thermal capacity that can be heated rapidly. The image heating device includes a fixing belt (20) having a heat resistance; a rotatable heat-generating roller (21), which is at least partially conductive and arranged in contact with an inner peripheral surface of the fixing belt (20); a fixing roller (22), the fixing roller and the heat-generating roller (21) movably suspending the fixing belt (20) therebetween; and a magnetization means (24) for heating the heat-generating roller (21) through magnetization, which is arranged outside the heat-generating roller (21). In this image heating device, the magnetization means (24) heats the heat-generating roller (21) through magnetization after a rotating operation of the heat-generating roller (21) is started.

Abstract: A heating device utilizing electromagnetic induction is provided with an induction heating unit that is opposed to a heating member and causes the heating member to heat through electromagnetic induction. The induction heating unit has an exciting coil for generating a magnetic field and a coil guide member on which the exciting coil is wound. The exciting coil is formed in at least two layers in such a manner that a first layer is formed on a circumferential surface of the coil guide member by winding a plurality of turns and a second layer is formed around and outside the first layer on the side opposite to the coil guide member, and winding of each of the second layer and following layers is started from a position close to a winding start position of the first layer.

Abstract: An image heating device having a predetermined amount of heat generation with a small electric current. The device includes a heat-generating roller (1) having magnetism and conductivity, an exciting coil (5) opposed to the peripheral face of the heat-generating roller (1) and adapted for allowing the heat-generating roller (1) to generate heat with electromagnetic induction. The exciting coil (5) is composed of a bundle of 60 copper wires of a 0.2 mm diameter are extended in the direction of the rotation axis of the heat-generating roller (1) and they are circumferentially wound along the circumferential direction of the heat-generating roller (1). The bundled wires are arranged in close contact with each other in the circumferential direction of the heat-generating roller (1) so as to cover the upper half of the heat-generating roller (1).