Toner End Detection; Toner End Recovery - Ricoh B064 Service Manual

Toner End Detection

The toner end sensor is checked every copy.
• Toner near end. When the toner end sensor remains on for two consecutive
pages, the toner supply motor turns on for 1.1 s. If the toner supply motor has
turned on more than 30 times during the last 100 prints, the "Toner Near End"
warning is issued. The warning is cleared if the toner end sensor turns off.
• Toner end. If the toner end sensor remains on for about 1,000 copies (A4 size
with 6% coverage), the "Toner End" warning is issued. If the toner end sensor
switches off twice consecutively, the toner end sensor copy counter is reset to
zero.

Toner End Recovery

If the front door is opened and closed while a toner near end or toner end condition
exists, the machine attempts to recover using measurements from the toner end
sensor and TD sensor, based on the possibility that the toner bottle has been
replaced.
1. The drum development motor, charge grid, and development bias switch on.
2. The toner supply motor switches on for 1.1 s, the toner supply clutch switches
on for 1 s, and the CPU checks the toner end sensor output.
3. If the toner end sensor is OFF, i.e. there is toner in the hopper, the CPU
compares Vt and Vref.
• If Vt is less than or equal to Vref, there is sufficient toner in the development
unit. The CPU waits 20 s for the toner in the developer to mix evenly, the
above components switch off, and the machine is released from the toner
end or toner near end status.
• If Vt is more than Vref, the CPU turns on the toner supply clutch for 1 s again
until Vt becomes less than or equal to Vref.
• If the toner end sensor output remains on even after seven attempts of the
above procedure, the components switch off and the machine remains in the
"Toner End" status.
SM
DEVELOPMENT AND TONER SUPPLY
6-77 B064 Series/B140 Series/G126