Patent ID: 6988727

Claim:
A sheet conveyance apparatus comprising: a rotary member for conveying a sheet; wearing degree detecting means for detecting lowered conveyance performance due to wear of the rotary member; time managing means for measuring operation time of the rotary member; limit wearing degree memorizing means for memorizing in advance a limit wearing degree immediately before the rotary member becomes unable to make conveyance due to wear; and duration estimating means for estimating a time at which the rotary member becomes unable to make conveyance due to wear; wherein the duration estimating means uses the wearing degree of the rotary member detected by the wearing degree detecting means, the operation time of the rotary member measured by the time managing means, and the limit wearing degree memorized by the limit wearing degree memorizing means, to calculate according to an estimation function the time ending the duration at which the rotary member becomes unable to make conveyance due to wear.