Abstract: A heater used for a fixing device includes a substrate, first and second conductor patterns formed at either end of the substrate in the short direction of the substrate, a third conductor pattern formed between the first and second conductor patterns and separated from the two conductor patterns, a first heating member disposed between the first and third conductor patterns and electrically connected to the two conductor patterns, and a second heating member disposed between the second and third conductor patterns and electrically connected to the conductor patterns. The heater has both end regions in which the widths of the third conductor pattern in the short direction is smaller than that of a middle portion of the third conductor pattern. The widths of the first and second heating members in the end regions are smaller than the widths of the first and second heating members in the other region, respectively.

Abstract: An image heating apparatus for heating a toner image in a nip while conveying a recording material on which the toner image is held is provided. The image heating apparatus includes: a heater configured to generate heat by being supplied with electric power from an AC power source; a rotatable heating member configured to be heated by the heater; a pressing member configured to form the nip in contact to the rotatable heating member; a temperature detecting portion configured to detect a temperature of the heater or the rotatable heating member; and a controller configured to set the electric power supplied to the heater every renewal cycle depending on a detected temperature by the temperature detecting portion. The renewal cycle is shorter in a rise period of the heater than in a period in which the recording material is conveyed in the nip.

Abstract: A fixing device for fixing on a recording material a toner image formed on the recording material includes: a flexible sleeve including a resinous base layer, a parting layer, and an adhesive layer for bonding the base and parting layers; a heater contacting the sleeve; a pressor for forming a nip with the sleeve, in which the recording material is nipped and conveyed; a member for applying a voltage, with the same polarity as toner; and a grounder contacting the recording material in the nip, for grounding the recording material. In a thickness direction of the layers, the electric resistance of the adhesive layer is larger than that of the parting layer, which is larger than that of the base layer. The member applies the voltage to the sleeve in contact with the base layer.

Abstract: The present invention relates to an image heating apparatus in which a nip portion is formed by a heating unit, which includes a flexible sleeve and a heater, and a pressure roller. The position of the heating unit is appropriately maintained by pressing the heating unit against the pressure roller using a pressure member so that the heating unit can contact two or more portions of a downstream side rim of a groove arranged on a frame that holds the heating unit, even when the pressure roller is rotated.

Abstract: An image heating apparatus for heating a toner image in a nip while conveying a recording material on which the toner image is held is provided. The image heating apparatus includes a heater for generating heat by being supplied with electric power from an AC power source; a rotatable heating member for being heated by the heater; a pressing member for forming the nip in contact to the rotatable heating member; a temperature detecting portion for detecting a temperature of the heater or the rotatable heating member; and a controller for setting the electric power supplied to the heater every renewal cycle depending on a detected temperature by the temperature detecting portion. The renewal cycle is shorter in a rise period of the heater than in a period in which the recording material is conveyed in the nip.

Abstract: The present invention relates to an image heating apparatus in which a nip portion is formed by a heating unit, which includes a flexible sleeve and a heater, and a pressure roller. The position of the heating unit is appropriately maintained by pressing the heating unit against the pressure roller using a pressure member so that the heating unit can contact two or more portions of a downstream side rim of a groove arranged on a frame that holds the heating unit, even when the pressure roller is rotated.

Abstract: The present invention relates to an image heating apparatus in which a nip portion is formed by a heating unit, which includes a flexible sleeve and a heater, and a pressure roller. The position of the heating unit is appropriately maintained by pressing the heating unit against the pressure roller using a pressure member so that the heating unit can contact two or more portions of a downstream side rim of a groove arranged on a frame that holds the heating unit, even when the pressure roller is rotated.

Abstract: An image heating device for heating a toner image while nip-conveying a recording material, in a nip, on which the toner image is carried, includes a heating member; and a pressing roller, including an elastic layer, for forming the nip in contact with the heating member. The elastic layer of the pressing roller includes a thermosetting silicon rubber containing a thermal conductive filler. The thermosetting silicon rubber includes pore portions formed with resin microballoons and a pore connecting portion for connecting the pore portions. The elastic layer has a thermal conductivity of 0.15 W/mK to 0.5 W/mK.

Abstract: A fixing device for fixing on a recording material a toner image formed on the recording material includes a flexible sleeve including a resinous base layer, a parting layer and an adhesive layer for bonding the base layer and the parting layer; a heater contacted to an inner surface of the sleeve; a pressing member for forming a nip, in which the recording material on which the toner image has been formed is nipped and conveyed, between itself and the sleeve to which the heater is contacted; a voltage applying member for applying a voltage, of a polarity identical to a polarity of toner; and a grounding member, contactable to the recording material in a nipped state in the nip, for grounding the recording material. In a thickness direction of the layers, an electric resistance of the adhesive layer is larger than that of the parting layer and the electric resistance of the parting layer is larger than that of the base layer.

Abstract: An image heating apparatus for heating an image formed on a recording material, including a heating unit having a heater and a flexible sleeve to be rotated in contact with the heater; an elastic roller for constituting a nip portion, in cooperation with the heater and through the flexible sleeve, for heating the recording material under pinching and conveying; and a frame having a roller supporting portion for supporting the heating unit and the elastic roller; wherein the frame has a guide portion for mounting the heating unit on the frame; and the roller supporting portion of the frame is positioned, in a conveying direction of the recording material, in a downstream position of an imaginary line passing through a center of the guide portion.

Abstract: The present invention relates to an image heating apparatus in which a nip portion is formed by a heating unit, which includes a flexible sleeve and a heater, and a pressure roller. The position of the heating unit is appropriately maintained by pressing the heating unit against the pressure roller using a pressure member so that the heating unit can contact two or more portions of a downstream side rim of a groove arranged on a frame that holds the heating unit, even when the pressure roller is rotated.

Abstract: An image forming apparatus prevents defective fixing of a toner image from occurring and shortens a printout time for a first sheet by determining a start timing for conveying the recording medium to a transferring position of the toner image in accordance with a warm-up state of a fixing unit, a voltage state of a power supply, and an environmental temperature.

Abstract: An image forming apparatus prevents defective fixing of a toner image from occurring and shortens a printout time for a first sheet by determining a start timing for conveying the recording medium to a transferring position of the toner image in accordance with a warm-up state of a fixing unit, a voltage state of a power supply, and an environmental temperature.

Abstract: Image heating apparatus capable of preventing an excessive temperature increase in a sheet non-passing area and heater for use in the image heating apparatus including: a substrate, a heat generating resistor formed on the substrate, and first and second electrodes for supplying an electric power to the heat generating resistor. Each of the first and second electrodes has a first area to contact a power supplying connector and a second area provided at an end portion electrically opposite to the first area along a longitudinal direction of the substrate, and the heat generating resistor is provided to electrically connect the second area of the first and second electrode so that when the heater is at a set temperature for an image heating operation a resistance value Rc of the second area, and a resistance value Rt between a portion within the second area of the first and second electrode and electrically closest to the first area satisfy a relation Rc/Rt<=1/30.

Abstract: An image heating apparatus for heating an image formed on a recording material, including a heating unit having a heater and a flexible sleeve to be rotated in contact with the heater; an elastic roller for constituting a nip portion, in cooperation with the heater and through the flexible sleeve, for heating the recording material under pinching and conveying; and a frame having a roller supporting portion for supporting the heating unit and the elastic roller; wherein the frame has a guide portion for mounting the heating unit on the frame; and the roller supporting portion of the frame is positioned, in a conveying direction of the recording material, in a downstream position of an imaginary line passing through a center of the guide portion.

Abstract: An image-forming apparatus includes a pre-charge exposure device which removes electric charge from a photoconductor drum to increase a potential contrast between the surface of the photoconductor drum and the surface of a charge roller in an upstream region of a nip region between the photoconductor drum and the charge roller in the rotating direction of the photoconductor drum, so that toner accumulating in an upstream region of the nip region in the rotating direction of the photoconductor drum is restrained and prevented from being discharged onto an image-forming region. When the toner accumulating in the upstream region of the nip region in the rotating direction of the photoconductor drum is to be discharged onto a non-image-forming region, the pre-charge exposure device is turned off so that the potential contrast decreases.

Abstract: To provide a transferring apparatus, it is possible to perform switching between a high mode and a low mode in a transfer voltage generator circuit of a transferring apparatus by using a microcomputer. The high mode is a mode in which a positive transfer voltage generator circuit is operated independently, and a voltage generated by the positive transfer voltage generator circuit is output as a transfer voltage. The low mode is a mode in which the positive transfer voltage generator circuit and a negative transfer voltage generator circuit are both operated, and the voltages generated by each of the circuits are superimposed and output as the transfer voltage.

Abstract: The invention is to provide an image heating apparatus capable of preventing an excessive temperature increase in a sheet non-passing area and a heater for use in such apparatus, and the heater for use in the image heating apparatus of the invention is constructed by including: a substrate; a heat generating resistor formed on the substrate; and first and second electrodes for supplying an electric power to the heat generating resistor; wherein each of the first and second electrodes has a first area to be contacted with a power supplying connector and a second area provided at an end portion electrically opposite to the first area, the second areas are provided along a longitudinal direction of the substrate, and the heat generating resistor is so provided as to electrically connect the second area of the first electrode and the second area of the second electrode; wherein, within the second area of the first electrode, a portion electrically closest to the first area of the first electrode is provided in th

Abstract: An image-forming apparatus includes a pre-charge exposure device which removes electric charge from a photoconductor drum to increase a potential contrast between the surface of the photoconductor drum and the surface of a charge roller in an upstream region of a nip region between the photoconductor drum and the charge roller in the rotating direction of the photoconductor drum, so that toner accumulating in an upstream region of the nip region in the rotating direction of the photoconductor drum is restrained and prevented from being discharged onto an image-forming region. When the toner accumulating in the upstream region of the nip region in the rotating direction of the photoconductor drum is to be discharged onto a non-image-forming region, the pre-charge exposure device is turned off so that the potential contrast decreases.

Abstract: To provide a transferring apparatus, it is possible to perform switching between a high mode and a low mode in a transfer voltage generator circuit of a transferring apparatus by using a microcomputer. The high mode is a mode in which a positive transfer voltage generator circuit is operated independently, and a voltage generated by the positive transfer voltage generator circuit is output as a transfer voltage. The low mode is a mode in which the positive transfer voltage generator circuit and a negative transfer voltage generator circuit are both operated, and the voltages generated by each of the circuits are superimposed and output as the transfer voltage.