Body of revolution the seat conveyer and the picture formation device and the body of revolution

摘要

PROBLEM TO BE SOLVED: To provide a life predicting method capable of accurately predicting service life of a roller.;SOLUTION: A sheet conveying device comprises a roller for conveying a sheet, a sheet detecting sensor 33 and a controller 40 for detecting degradation of conveying performance by consumption of the roller, a clock function in the controller 40 for measuring an operation time of the roller, a memory in the controller 40 for previously storing a limit consumption degree just before the consumption disables the conveyance of the roller, and the controller 40 for predicting a time when the consumption disables the conveyance of the roller. The controller 40 calculates the service life when the consumption disables the conveyance of the roller with a prediction function, using the consumption degree of the roller detected by the sheet detecting sensor 33 and the controller 40, the operation time of the roller measured by the clock function in the controller 40, and the limit consumption degree stored in the memory in the controller 40.;COPYRIGHT: (C)2003,JPO