Abstract: A cylindrical body includes a cylindrical member, made by forming a metal plate into a cylindrical shape such that the two end faces of the metal plate face each other, and a nonmetallic adhesive member bonding the two end faces together. The two end faces each include an adhesive part, and the adhesive member is disposed between the adhesive parts of the end faces. The adhesive part of one end face is not parallel to the adhesive part of the other end face. Each end face also includes a contact part which is in contact with the contact part of the other end face.

Abstract: According to at least one embodiment, an image forming apparatus includes a heater and a controller. The heater is configured to generate heat. The controller is configured to control AC power to the heater so that a part of the AC power which exceeds a threshold voltage is not applied to the heater.

Abstract: A fixing device includes a plurality of heating elements, a plurality of first terminals, a second terminal, a movable member, a first conductive circuit and a second conductive circuit. The heating elements are arranged in a main scanning direction and generate heat. The first terminals are electrically connected to the heating elements. The second terminal is electrically connected to a power supply that supplies electric power to the heating elements. The first conductive circuit and the second conductive circuit are provided on a surface of the movable member. The first conductive circuit is configured to electrically connect a first combination of one or more of the first terminals with the second terminal. The second conductive circuit is configured to electrically connect a different, second combination of one or more of the first terminals with the second terminal.

Abstract: A fixing device includes a plurality of heating elements, a plurality of first terminals, a second terminal, a movable member, a first conductive circuit and a second conductive circuit. The heating elements are arranged in a main scanning direction and generate heat. The first terminals are electrically connected to the heating elements. The second terminal is electrically connected to a power supply that supplies electric power to the heating elements. The first conductive circuit and the second conductive circuit are provided on a surface of the movable member. The first conductive circuit is configured to electrically connect a first combination of one or more of the first terminals with the second terminal. The second conductive circuit is configured to electrically connect a different, second combination of one or more of the first terminals with the second terminal.

Abstract: According to at least one embodiment, an image forming apparatus includes a voltage measuring device, a fixing device, and a controller. The voltage measuring device measures an input voltage. The fixing device includes a heater that heats a sheet. When the measured voltage becomes equal to or greater than a threshold value, the controller determines a heating timing of the heater based on the voltage and activates the heater at the determined heating timing.

Abstract: A heating device includes a rotatable film, a heater including a substrate that extends along a first direction and having two surfaces opposite to each other, and a heater element on one of the surfaces of the substrate, and a heat conductor having first and second surfaces and including a first portion contacting the other surface of the substrate, and a second portion that is adjacent to the first portion in a second direction perpendicular to the first direction and does not contact the other surface of the substrate. A thickness of the first portion of the heat conductor from the first surface to the second surface is greater than a thickness of the second portion from the first surface to the second surface.

Abstract: A fixing unit or device that can be used in an image forming apparatus includes a first heater element that is formed of a material that increases in electrical resistance with increases in temperature. A controller of the fixing unit is configured to vary a duty ratio of electric power applied to the first heater element during a start-up operation in which the temperature of the first heater element is raised to a target operating temperature. By varying the duty ratio during the start-up operation, changes in the resistance of the first heater element with the heating can be compensated. For example, the duty ratio can be increased during the course of the start-up to achieve the target operating temperature faster.

Abstract: An image processing apparatus includes a fixing unit including a fixing belt, and a heater configured to heat the fixing belt and including a substrate and a heating layer that is formed on the substrate, and a controller configured to, upon detecting an absence of a current flowing through the fixing belt, control the heater to not generate heat.

Abstract: A heating device includes a rotatable film, a heater including a substrate that extends along a first direction, and a heater element on the substrate and facing the film, a heat conductor having first and second surfaces and including a first portion contacting the substrate, and a second portion that is adjacent to the first portion in a second direction perpendicular to the first direction and does not contact the substrate, and a temperature sensing element on the second surface at a position corresponding to the second portion. A thickness of the first portion from the first surface to the second surface is greater than a thickness of the second portion from the first surface to the second surface.

Abstract: A fixing unit or device that can be used in an image forming apparatus includes a first heater element that is formed of a material that increases in electrical resistance with increases in temperature. A controller of the fixing unit is configured to vary a duty ratio of electric power applied to the first heater element during a start-up operation in which the temperature of the first heater element is raised to a target operating temperature. By varying the duty ratio during the start-up operation, changes in the resistance of the first heater element with the heating can be compensated. For example, the duty ratio can be increased during the course of the start-up to achieve the target operating temperature faster.

Abstract: An image processing apparatus includes a fixing unit including a heater and a fixing belt. The fixing belt is electrically connected between a first power source and a ground terminal. A controller is configured to control the heater to heat the fixing belt. The controller is further configured to determine whether a current is flowing through the fixing belt and, upon determining that a current is not flowing through the fixing belt, control the heater not to heat the fixing belt.

Abstract: According to at least one embodiment, an image forming apparatus includes a voltage measuring device, a fixing device, and a controller. The voltage measuring device measures an input voltage. The fixing device includes a heater that heats a sheet. When the measured voltage becomes equal to or greater than a threshold value, the controller determines a heating timing of the heater based on the voltage and activates the heater at the determined heating timing.

Abstract: An image forming apparatus according to one or more embodiments includes a fixing device and a controller. The fixing device includes a first heating source and a second heating source. The second heating source has a heating width greater than that of the first heating source. The first and second heating sources have different heating characteristics in response to temperature increases. The controller selects one of the first heating source and the second heating source according to a size of a sheet on which printing is to be performed.

Abstract: An image forming apparatus according to one or more embodiments includes a fixing device and a controller. The fixing device includes a first heating source and a second heating source. The second heating source has a heating width greater than that of the first heating source. The first and second heating sources have different heating characteristics in response to temperature increases. The controller selects one of the first heating source and the second heating source according to a size of a sheet on which printing is to be performed.

Abstract: A heating device includes a cylindrical film configured to be rotated about an axis, a heater including a substrate that extends along a longitudinal direction parallel to the axis, and a heater element on the substrate and facing an inner surface of the cylindrical film. A heat conductor extends along the longitudinal direction and has first and second surfaces. A first portion of the heat conductor contacts the substrate and a second portion of the heat conductor has a groove in the first surface. A temperature sensing element is disposed at a position on the second surface at a position opposite the groove.

Abstract: A heating device includes a rotatable film, a heater including a substrate that extends along a first direction, and a heater element on the substrate and facing the film, a heat conductor having first and second surfaces and including a first portion contacting the substrate, and a second portion that is adjacent to the first portion in a second direction perpendicular to the first direction and does not contact the substrate, and a temperature sensing element on the second surface at a position corresponding to the second portion. A thickness of the first portion from the first surface to the second surface is greater than a thickness of the second portion from the first surface to the second surface.

Abstract: An image forming apparatus includes a heater, a fixing device, and a controller. The heater includes a heat generator that generates heat when the heater is turned on. The fixing device may fix a developer image on a surface of an image forming medium using the heat from the heat generator. The controller detects a voltage of a power supply for supplying electric power to the heater, and determines an occurrence of an abnormality in the heater if a voltage drop amount at the time the heater is turned on as compared to a case in which the heater is turned off is smaller than a first threshold value.

Abstract: An image processing apparatus includes a fixing unit including a heater and a fixing belt. The fixing belt is electrically connected between a first power source and a ground terminal. A controller is configured to control the heater to heat the fixing belt. The controller is further configured to determine whether a current is flowing through the fixing belt and, upon determining that a current is not flowing through the fixing belt, control the heater not to heat the fixing belt.

Abstract: An image forming apparatus according to one or more embodiments includes a fixing device and a controller. The fixing device includes a first heating source and a second heating source. The second heating source has a heating width greater than that of the first heating source. The first and second heating sources have different heating characteristics in response to temperature increases. The controller selects one of the first heating source and the second heating source according to a size of a sheet on which printing is to be performed.

Abstract: An image processing apparatus includes a fixing unit including a heater and a fixing belt. The fixing belt is electrically connected between a first power source and a ground terminal. A controller is configured to control the heater to heat the fixing belt. The controller is further configured to determine whether a current is flowing through the fixing belt and, upon determining that a current is not flowing through the fixing belt, control the heater not to heat the fixing belt.