Abstract:
Provided is a belt member used in a fixing device of an electromagnetic induction heating system. The belt member includes an endless resin base layer, heat layers, and an insulating resin layer. The heat layers are two or more layers including a non-magnetic metal stacked on the resin base layer. The insulating resin layer is an insulating layer stacked between the heating layers.
Abstract:
The fixing device (13) includes the fixing belt (20), the pressuring roller (21) and the pad (24). The pad (24) sandwiches the belt (20) with the roller (21) to form the fixing nip. The pad (24) is extended in the nip width direction, and the pressing face (40) has the first and second curved faces (41) and (42) at upstream and downstream sides in the sheet conveyance direction. The first and second curved faces (41) and (42) are formed arch-like curved to the roller (21) toward upstream and downstream sides. The first and second curved faces (41) and (42) continue at the inflection point (B) near the intersection point of the extending line (A) parallel to the pressuring direction and through the rotation center of the roller (21) on the pressing face (40). The first curved face (41) has the curvature radius (Ra) larger than the second curved face (42).
Abstract:
A fixing device includes a fixing belt, a belt guide, a pressuring member, a heat source and an excessive temperature rise preventing device. The guide contacts with the inside of the belt to assist the belt's rotation track. The heat source is located across the belt to the pressuring member to induction-heat the belt. The preventing device has first and second lead wires connected at one and another end sides in an axial direction of the belt and prevents excessive temperature rise of the guide in noncontact. The first lead wire is extended to one end side and pulled out from the inside to the outside via one end side in the belt. The second lead wire is extended to another end side, curved toward one end side, extended to one end side and pulled out from the inside to the outside via one end side in the belt.
Abstract:
A fixing device includes a heating member, a pressurizing member, a coil wound in a loop shape in the width direction of the heating member to generate a magnetic flux that inductively heats the heating member, and a magnetic core adjacent to the coil. The magnetic core is configured to apply the magnetic flux to an inductive heat-generating layer of the heating member. The magnetic core includes first core parts and second core parts. The first core parts are positioned to enclose the coil in a direction orthogonal to a direction in which paper is conveyed. The second core parts are placed in hollow areas formed by the loops of the coil at both ends in the direction orthogonal to the paper conveyance direction. The second core parts have a higher Curie temperature and a lower thermal capacity than the first core parts.
Abstract:
A fixing device includes an auxiliary duct. The auxiliary duct is provided between a cover member attached to a coil bobbin so as to cover a magnetic core and a coil, and a core holder provided opposing to the coil bobbin, to which the magnetic core is attached. The auxiliary duct communicates with an intake hole provided at one end in a longitudinal direction of the cover member, and has opening holes overlapping with some of holder opening portions formed on the core holder. The fixing device causes air to flow into between the core holder and the coil bobbin via the auxiliary duct and the holder opening portions from the intake hole, and discharges the air warmed by heat of the coil from an exhaust hole formed at the other end of the cover member, thereby adjusting the flowing amount of air in a longitudinal direction of the coil.
Abstract:
A frequency determining portion determines a driving frequency of an induction heater. A determination processing portion determines whether or not the driving frequency determined by the frequency determining portion is within a predetermined prohibited frequency band. A frequency changing portion, when the driving frequency determined by the frequency determining portion is within the prohibited frequency band and is lower than a predetermined threshold within the prohibited frequency band, changes the driving frequency to a frequency equal to or lower than a lower boundary frequency of the prohibited frequency band, and when the driving frequency is within the prohibited frequency band and is equal to or higher than the threshold, changes the driving frequency to a frequency equal to or higher than a higher boundary frequency of the prohibited frequency band. A heating control portion drives the induction heater by the driving frequency changed by the frequency changing portion.
Abstract:
A fixing device includes a fixing belt, a pressuring member, an exciting coil and a belt guide. The pressuring member comes into pressure contact with the fixing belt to form a fixing nip. The exciting coil is provided at an outer diameter side of the fixing belt and configured to generate a magnetic flux to inductively heat the fixing belt. The belt guide supports the fixing belt from an inner diameter side. The belt guide includes a contact part which is in contact with an inner circumferential face of the fixing belt and a non-contact part which is not in contact with the inner circumferential face of the fixing belt. The non-contact part is provided with a slit configured to inhibit induction heating of the non-contact part due to the magnetic flux generated by the exciting coil.
Abstract:
A fixing device includes a fixing belt, a pressuring member, an exciting coil and a belt guide. The pressuring member comes into pressure contact with the fixing belt to form a fixing nip. The exciting coil is provided at an outer diameter side of the fixing belt and configured to generate a magnetic flux to inductively heat the fixing belt. The belt guide supports the fixing belt from an inner diameter side. The belt guide includes a contact part which is in contact with an inner circumferential face of the fixing belt and a non-contact part which is not in contact with the inner circumferential face of the fixing belt. A magnetic flux blocking member configured to block the magnetic flux that passes through the fixing belt is provided between the fixing belt and the non-contact part.
Abstract:
A fixing device is provided with a fixing belt, a fixing roller inserted inside the fixing belt, a pressure roller that is pressed against the fixing belt, a coil that generates magnetic flux for induction heating of the fixing belt, and a belt regulating plate that is disposed at a side of an end surface of the fixing roller in a predetermined direction and regulates movement of the fixing belt in the predetermined direction. The belt regulating plate has a multi-layer structure including a resin plate disposed at a fixing belt side and a nonmagnetic metal plate disposed at a side opposite to the fixing belt side.
Abstract:
A fixing device includes a heating member, a pressurizing member, a coil wound in a loop shape in the width direction of the heating member to generate a magnetic flux that inductively heats the heating member, and a magnetic core adjacent to the coil. The magnetic core is configured to apply the magnetic flux to an inductive heat-generating layer of the heating member. The magnetic core includes first core parts and second core parts. The first core parts are positioned to enclose the coil in a direction orthogonal to a direction in which paper is conveyed. The second core parts are placed in hollow areas formed by the loops of the coil at both ends in the direction orthogonal to the paper conveyance direction. The second core parts have a higher Curie temperature and a lower thermal capacity than the first core parts.