| 摘要 |
PURPOSE:To allow the accurate measurement of the passage time of a recording medium most approximate to the service life of a process unit by detecting the cumulative printing length of the recording medium by utilizing the rotating motion of a rotating member which rotates only when the recording medium is inserted. CONSTITUTION:Gear trains 24a... are extended along the lower surface side of a recording paper transporting path on a device body 2 side down to the underside of the position where a counter 16 is mounted. The detecting device is so constituted that a stepping lever 26 is oscillated to step a counter 16 by utilizing a projection 25 provided on the gear 24h mounted at the extreme downstream position of the above- mentioned gear trains at every one rotation of the gear 24h. The gear trains 24a... are so set with a speed reduction ratio that the gear 24h rotates every time when the resist rollers pass the recording paper of, for example, A-4 size. Relay gears 27a, 27b are meshed with the gear 24 to allow stepping of a total counter 28 provided to the device body 2 side so that the total cumulative printing length can be detected on the device body 2 side. The passage time of the recording medium most approximate to the service life of the process unit is accurately measured in this way. |
