An image forming apparatus includes a transfer portion to transfer a toner image to a recording material, a fixing portion having a heating unit and a cylindrical rotary member and to fix the toner image to the recording material, a fixing drive portion to drive the cylindrical rotary member, and a controller. In a case in which images are formed on a plurality of recording materials, the controller controls the fixing drive portion based on a time period from a time when a trailing edge of a preceding recording material passes through the fixing portion to a time when a leading edge of a subsequent recording material passes through the fixing portion so that a second rotation speed of the cylindrical rotary member when conveying the subsequent recording material becomes lower than a first rotation speed of the cylindrical rotary member when conveying the preceding recording material.

An example image forming apparatus includes an endless belt to rotate, belt rollers including a tension roller and an adjustment roller extending inside the endless belt, a nip roller extending adjacent the endless belt to form a nip between the nip roller and the endless belt, and a cam shaft that includes a nip forming cam and a tension adjustment cam. The nip forming cam moves the nip roller between a pressed position in which the nip roller is pressed against the endless belt, and a retracted position in which the nip roller is retracted from the endless belt. The tension adjustment cam moves the adjustment roller relative to the tension roller.

A heating device includes a first rotator, a second rotator, a heater, and a first, second and third temperature sensors. The second rotator contacts an outer circumferential surface of the first rotator to form a nip through which a recording medium passes. The heater heats the first rotator. The first temperature sensor is disposed outside a space extending from a first region through which a minimum recording medium passes and detects the temperature of the first rotator. The second temperature sensor is disposed outside the space extending from the first region and detects the temperature of the heater. The third temperature sensor is disposed outside the space extending from the first region and detects the temperature of the second rotator. At least one of the second temperature sensor or the third temperature sensor is disposed outside a space extending from a second region through which a maximum sheet passes.

A heating apparatus includes a cylindrical film and a pressing element that rotates with the cylindrical film and forms a nip with the cylindrical film. A medium is conveyed through the nip from an upstream side to a downstream side. The heating apparatus further includes a heater arranged inside the cylindrical film and on which a heating element is disposed. An upstream end of the heater is located downstream of an upstream end of the nip, and a downstream end of the heater is located downstream of a downstream end of the nip.

Embodiments disclosed herein generally relate to a heater, comprising an insulator substrate, a first member, a plurality of electrodes, and a second member. The first member is configured to generate heat on an upper surface of the insulator substrate across a first direction. The first member has a first end opposite a second end. The plurality of electrodes are formed on both the first end and the second end of the first member, respectively, and each electrode is disposed in a direction perpendicular to the first direction. The second member is configured to store heat. The second member comprises a latent heat material having latent heat in a target temperature zone. Furthermore, the latent heat material is fixed to a side surface or a bottom surface of the insulator substrate.

A device includes a rotator having a rotation axis, a belt, a nip forming member surrounded by the belt and configured to, with the rotator, pinch the belt to form a nip, an urging member configured to urge one of the rotator and the nip forming member towards the other in a particular direction perpendicular to the rotation axis, an upstream guide and a downstream guide. The upstream guide includes an upstream guide surface configured to guide an inner peripheral surface of the belt. The nip forming member includes a facing surface which faces the rotator. An upstream edge of the facing surface in the moving direction is located at a position farther from the rotation axis, in the particular direction, than a downstream edge of the upstream guide surface.

A heating efficiency 600 includes a substrate 610 and a plurality of heat generating elements 523a to 623f which are provided on both surfaces of the substrate 610 and which generate heat, and heats a fixing belt in contact with an inner peripheral surface of the fixing belt. The plurality of heat generating elements 623a to 623f are different from each other in length with respect to a widthwise direction, and at least three of the heat generating elements are provided on a front surface of the substrate 610 which is a side where the heater 600 contacts the inner peripheral surface of the fixing belt 600, and at least one of the heat generating elements is provided on a back surface. A longest heat generating element 623b, in length with respect to the widthwise direction, of the plurality of heat generating elements 623a-623f is provided on the front surface. Further, as regards the heat generating elements 523a-623c provided on the front surface, with respect to a rotational direction of the fixing belt, the longest heat generating element 623b in length with respect to the widthwise direction is disposed between the heat generating element 623a and the heat generating element 623c.

An image forming apparatus includes an endless belt to rotate, belt rollers including a tension roller and an adjustment roller extending inside the endless belt, a nip roller extending adjacent the endless belt to form a nip between the nip roller and the endless belt, and a cam shaft that includes a nip forming cam and a tension adjustment cam. The nip forming cam moves the nip roller between a pressed position in which the nip roller is pressed against the endless belt, and a retracted position in which the nip roller is retracted from the endless belt. The tension adjustment cam moves the adjustment roller relative to the tension roller.

A transport device includes a rotating body including a recessed portion on an outer surface, a rotatable heat unit that is in contact with the outer surface of the rotating body and forms an interposition region in which a recording medium is interposed between the heat unit and the rotating body, a transport unit that: (i) includes a hold member capable of holding a portion of the recording medium near a leading edge, (ii) transports the recording medium by moving the hold member in a rotational direction of the rotating body with the hold member contained in the recessed portion, and (iii) causes the hold member to pass through the interposition region, and a controller that controls rotation of the rotating body such that the recessed portion stops at a position upstream or downstream of the interposition region in the rotational direction when an anomaly is detected.

A heating device includes a heater, a rotator, and a pressure rotator. The heater includes resistive heat generators forming a heat generation area and has a separation area formed by the resistive heat generators. The pressure rotator includes a first region and a second region. The first region faces the heater in a range of 20 mm from a center position of the heat generation area toward an end thereof in the arrangement direction. The second region faces the heater in at least a part of a range of 30 mm from a center position of the separation area toward the center position of the heat generation area. An outer diameter of the pressure rotator increases from the center toward the end. The outer diameter of the second region increases at an increasing rate larger than an increasing rate of the outer diameter of the first region.