| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device in which eliminating waste warming-up time prevents working efficiency from reducing and saves energy. SOLUTION: The image forming device reads job data for past one week out of a history storing memory (831), and converts number of sheets copied for each job data to number of A4-sized recording sheets (832). The image forming device divides each number of jobs after the data conversion to classes by number of 100 copied sheets for each job and creates a Parate graph representing cumulative sum (833), sets a sheet class of the job number which occupies 80% of total job number in the Parate graph (834), and assumes the maximum number of sheets for the set class as number of sheets copied in the hereafter processed job (835). Then it calculates an optimum fixing temperature Ta for copying sheets sequentially by set number of copied sheets on the basis of pre-stored data (836), and finishes warming-up to allow copy when temperature of the fixing roller reaches the optimum fixing temperature Ta. |
