Chapter 22-20A mechanism used in this control is also used in a developing rotary engaging operation.The developing rotary position detection is also performed by the DCNT Board monitoring the rotary engaging sensor (PS712).F-2-342.3.5.4 Cartridge Presence Detection 0007-4986This detection is utilized to detect the presence of the cartridge.When the power is turned on or the top cover is closed, the DCNT Board reads in data (cartridge ID) from the memory tags in each toner cartridge. When the DCNTBoard successfully reads data, it determines a cartridge presence.If the DCNT Board determines a cartridge out, it notifies the error to the SCNT Board.2.3.5.5 Toner Cartridge Life Detection 0007-4987a. OutlineThis detection is utilized to detect whether the toner cartridge has reached the end of its life.When the power is turned on or the top cover is closed, the DCNT Board monitors the following two items. It determines an toner cartridge end-of-life if either ofthe items reaches its specified value.a. Developing cylinder life (usage hour)b. Toner levelThe life of the toner cartridge is indicated to the SCNT Board in 2 steps (warning, end of life); the printer engine will be stopped only when the end of life has beenreached. The life of the developing cylinder and the level of remaining toner are checked as follows:b. Developing cylinder life detectionThe life of the developing cylinder is detected by the DCNT Board monitoring the cumulative usage hours of the developing cylinder, which stored in the memorytag.Developing cylinder usage hour (DC application time) data sent from the DCNT Board is written in the memory tag in the toner cartridge. The DCNT Board updatesdata with specified timing. If updated data, developing cylinder cumulative usage hours, reaches a specified value, the DCNT Board determines a developing cyl-inder end-of-life.c. Toner level detectionThis printer utilizes a through-beam sensor for toner level detection.The toner level is detected by the DCNT Board monitoring the toner level detection unit structured with a light emitter (LED) and a light receiver (PD) (Note:1).After the start of a print operation, the DCNT Board emits light from the LED with the LED DRIVE (P3.3V) signal. The light emitted from the light emitter passesthrough the light guide in the cartridge and enters into the cartridge. The light passes through it and again the light guide. Then the light is detected at the lightreceiver and output as the TONER LEVEL DETECTION (TONS) signal to the DCNT Board. The DCNT Board detects the toner level from the cumulative detec-tion time of the TONS signal during one rotation of the stirrer in the cartridge.The DCNT Board determines that the toner level is low when the cumulative detection time of the TONS signal exceeds a specified value (Note:2).PhotosensitivedrumDeveloping rotary Drive gearEngaging motor(PM704)Memory tag contactengaging camMemory tagMemory tagcontactPhotosensitivedrumPressure plateEngaging camMemory tagMemory tagcontact
