Abstract:
A heating roller (21) has a heating layer (22) for electromagnetic induction heating, a heat insulating layer (23), and a support layer (24) from inside to outside in this order. The support layer (24) consists of a material with a specific resistance of 1 x 10 −5 Ωm or more. Thus, despite of thinning down the heating layer (22) below the skin depth that is a thickness for an induction current to flow to make a magnetic flux penetrate through the heating layer (22) and reach the support layer (24), the support layer (24) is blocked from heating by an eddy current. Therefore, reductions in the heat capacity of the heating layer (22) and the heating of the support layer (24) are suppressed. The efficient heating of only the heating layer (22) enables a shortening in warm−up time and prevents a bearing or the like for supporting the heating roller (21) from being damaged by heat.
Abstract:
An electromagnetic induction exothermic roller (21) having, in the order from the surface, at least a release layer, induction exothermic layer (22), an elastic layer (23), and a core (24). Exothermic roller (21) is pressed by a press member (31) to form a nip portion (34) and heat up a heating subject material (11) passing through the nip portion (34). The induction exothermic layer (22) has a layer prepared by dispersing an electrically conductive filler in the base material consisting of a heat resistant resin or heat resistant rubber. For this reason, the induction exothermic layer (22) can easily deform, so that a nip portion (34) having a large width (W) can be formed. Further, the durability of the induction exothermic layer (22) against repeated bending is improved.
Abstract:
A thermal conduction roller (10) has a tubular roller core (11) with an inside surface; and an electrical insulator coat (16) primarily of zirconia on the inside surface, a heater coat (18) of titania or a titania blend is disposed over the insulator coat (16), and at least two electrical contact assemblies that are disposed inside the roller and electrically connect to the heater coat (18) as the roller (10) is being rotated. One embodiment utilizes an electrical insulator coat (16) in a range of thickness from about ten mils to about twenty mils. A thinner coat may not have sufficient dielectric strength., while a thicker coat decrease thermal conduction. A release material (12) is applied to the outside of the roller (10). Various contact structure according to the present invention are also described to a three-phase power supply.
Abstract:
An image heating device having a predetermined heat generation rate with a low current. The device comprises a heating roller (1) having magnetism and conductivity, an exciting coil (5) opposed to the peripheral face of the heating roller (1) and adapted for allowing the heating roller (1) to produce heat with electromagnetic induction. The exciting coil (5) is composed of a bundle of sixty copper wires of a 0.2 mm diameter are extended toward the rotary shaft of the heating roller (1) and they are circumferentially wound along the circumferential direction of the heating roller (1). The bundled wires are arranged in close contact to each other in the circumferentially direction of the heating roller (1) so as to cover the upper half of the heating roller (1).
Abstract:
A quick heat roller used for fixing in an electrophotographic device, capable of a long service life and a high-speed heating and kept at a constant temperature, the roller comprising: a heating resistor sheet (8) formed by forming on the surface of an insulating layer (20) of a polyimide resin sheet a heating resistor layer (22) by silk screen printing, bonding a polyimide resin sheet as an insulating layer (24) and bonding on the surface thereof a heat reflection layer (26) of an aluminum foil; and a cylindrical body (6) which is formed by providing on the outer peripheral surface of an aluminum tube a releasing layer (4) for preventing the deposition of a developing toner and which has its inner peripheral surface pasted with the above heating resistor sheet (8).
Abstract:
The invention relates to uses of a flat heating element in a heatable pipe, a heatable transportation device and a heat roller, and to a flat heating element comprising a thin resistance layer containing an intrinsically electroconductive polymer and at least two flat electrodes arranged on one side of the resistance layer at a distance from each other.
Abstract:
Provided is a fixing device for preventing an increase in torque when a fixing belt starts to be driven. The fixing device may include a fixing belt that is rotatable; a pressure roller configured to pressure-contact an outer circumferential surface of the fixing belt and to form a fixing nip portion between the pressure roller and the fixing belt. A contact member is located inside the fixing belt and includes a contact portion that contacts an inner circumferential surface of the fixing belt. The contact portion includes a surface having a plate shape that faces the pressure roller and a plurality of protrusions that protrude from the surface toward the pressure roller.