| 摘要 |
PROBLEM TO BE SOLVED: To reduce a variation in temperature of a fixing belt caused by a decrease in temperature of a pressure roller to reduce temperature unevenness in a single sheet, and obtain uniform fixability of the sheet.SOLUTION: In a fixing device of the present invention, when a time period from a time when a leading edge of a recording medium reaches a nip part to a time when a rear edge passes the nip part is T1, a time period corresponding to an interval between recording media is T2, a control cycle is C, and N is a positive integer, a condition T1+T2=C×N is satisfied. Also, the control cycle and the interval between recording media are set such that heat quantity of a heat source is supplied to the recording medium in accordance with an entry timing of the recording medium to the nip part; a correction amount is added to an energization period of each control cycle on the basis of temperature information of a pressure member before the start of paper feed; and the correction amount is made to reduce at a predetermined rate in each control cycle and the correction amount is changed according to the basis weight of the recording medium. |
