摘要:
A fixing device includes a heat roller having a degaussing alloy material, an induction heating member for exciting the heat roller, an inverter circuit for giving power at a predetermined frequency to the induction heating member, and a control unit, and when driving at a first drive frequency and fixing small size sheets by continuous passing, a local temperature rise occurs at an end part of the heat roller, and the end part approaches the Curie temperature, and when impedance of the inverter circuit reduces and an excessive current flows in the circuit, the fixing device drives at a higher second drive frequency, thereby increases a resistance of the heat roller by an epidermal effect of magnetic flux, increases an apparent resistance of the inverter circuit, makes it possible to use a flowing current within a normal range, heating a central part of the heat roller, and continues the fixing.
摘要:
A fixing device includes a heat roller having a degaussing alloy material, an induction heating member for exciting the heat roller, an inverter circuit for giving power at a predetermined frequency to the induction heating member, and a control unit, and when driving at a first drive frequency and fixing small size sheets by continuous passing, a local temperature rise occurs at an end part of the heat roller, and the end part approaches the Curie temperature, and when impedance of the inverter circuit reduces and an excessive current flows in the circuit, the fixing device drives at a higher second drive frequency, thereby increases a resistance of the heat roller by an epidermal effect of magnetic flux, increases an apparent resistance of the inverter circuit, makes it possible to use a flowing current within a normal range, heating a central part of the heat roller, and continues the fixing.
摘要:
A technique of reducing temperature unevenness in a heating member which heats a heating target member while reducing heat capacity of the heating member in a fixing device for an image forming apparatus is provided. The fixing device has a heating member having diamond fine particles dispersed and contained at least in its surface layer, a pressurizing member which is pressed in contact with the heating member and nips and carries a sheet in collaboration with the heating member, and a heating unit which heats the heating member.
摘要:
According to an embodiment, a heating device having a plurality of heating members which heat the heating roller, a first thermoelectric converting section having a plurality of thermoelectric converting elements, each of which has a heat-absorbing surface and a cooling surface and generates electromotive force by difference in temperature between the heat-absorbing surface and the cooling surface, and formed along a curved surface of the heating roller, in which the heat-absorbing surface is disposed with a predetermined space from an outer circumferential surface of the heating roller, an auxiliary power supply charged with electric power generated by the first thermoelectric converting section, and a switching section which switches the apparatus between a first state in which electric power is supplied from utility power to the heating members and a second state in which electric power is supplied from the auxiliary power supply to the heating members, based on a predetermined signal.
摘要:
A fixing device of the invention detects a temperature of plural positions of a heat roller by a multiple non-contact temperature sensor at the same time and controls the temperature of plural heat source members The non-contact temperature sensor and a contact temperature sensor detect the temperature of the same position. According to the detection result, maintenance is performed or a temperature conversion table is corrected, the non-contact temperature sensor is maintained with high precision, and the heat roller is controlled the temperature with high precision.
摘要:
To provide a technique for preventing a temperature rise in a non-sheet passing areas in a fixing device. The fixing device includes: a heating rotational member that includes at least one roller and heats a toner transferred on a sheet; a pressing roller that nips and carries the sheet in cooperation with the heating rotational member; a heating device that heats the heating rotational member; and heat pipes arranged, on the inside of at least one of the roller of the heating rotational member and the pressing roller, in ranges on both the sides in an axial direction of the roller from positions closer to the center in the axial direction than both the ends of a minimum sheet passing range in the axial direction of the roller of the nipped and carried sheet to positions further on the outer sides in the axial direction than both the ends of a maximum sheet passing range.
摘要:
A fixing apparatus of the present invention includes a heating roller 2 that is a cylindrical member having a center axis, a pressurizing roller 3 that exerts pressure on the heating roller 2, and a temperature detecting element 6 that detects the temperature of the heating roller 2. The outer peripheral surface of the heating roller 2 is induction heated on the basis of the temperature information detected by the temperature detecting element 6. The fixing apparatus thus utilizes induction heating. The present invention is characterized in that the temperature detecting element 6 is placed in an area located vertically below the center axis of the heating member 2 and vertically below the outer peripheral surface of the heating member. The temperature detecting element 6 is thus provided at a position where it is unlikely to suffer thermal convection from the heating roller 2.
摘要:
In a fixing device of an image forming apparatus of the present invention, inner surfaces of upper and lower frames for respectively supporting a heat roller and a pressure roller are formed as a mirror surface. Between the heat roller and an infrared temperature sensor, an infrared transmission filter for cutting infrared rays beyond a wave length zone equivalent to a heatable area of the heat roller is installed. Detection results of a surface temperature of the heat roller by the infrared temperature sensor are prevented from exceeding the error tolerance due to infrared rays radiated from other than the heat roller. Temperature control for the heat roller is improved and a fixed image of high image quality is obtained.
摘要:
A fixing apparatus includes an endless heating member having a metallic conductive layer, and a pressure member pressed to the heating member to form a nip to hold and convey a medium to be fixed. The apparatus also includes an induction heating coil arranged on an outer periphery of the heating member to generate an induced current, and a position sensor to detect a front end of the medium conveyed. The apparatus further includes a controller for controlling so as to increase an output value of the induction heating coil.
摘要:
According to an embodiment, a heating device having a plurality of heating members which heat the heating roller, a first thermoelectric converting section having a plurality of thermoelectric converting elements, each of which has a heat-absorbing surface and a cooling surface and generates electromotive force by difference in temperature between the heat-absorbing surface and the cooling surface, and formed along a curved surface of the heating roller, in which the heat-absorbing surface is disposed with a predetermined space from an outer circumferential surface of the heating roller, an auxiliary power supply charged with electric power generated by the first thermoelectric converting section, and a switching section which switches the apparatus between a first state in which electric power is supplied from utility power to the heating members and a second state in which electric power is supplied from the auxiliary power supply to the heating members, based on a predetermined signal.