| 摘要 |
This invention provides a timing wheel assembly for controlling the timing of toner cartridge operation that is fixedly attached to a shaft of a toner tank agitator and that is operatively connected to a drive gear of a toner cartridge mounted coaxially on the shaft with the timing wheel movable between a first stop and a second stop relative to the drive gear to define rotational "dwell" range having a predetermined arcuate distance with a pair of springs of differing strengths. The first spring, of a first strength (first spring constant) biases the timing wheel against the first stop and the second spring of a second strength (second spring constant) is engaged by the timing wheel at higher resistance levels. In this manner, the first spring ensures that an appropriate dwell and snapback motion occurs at lower toner levels and the second spring (in combination with the first) provides heavier resistance and stronger rotational resistance/earlier snapback at higher toner levels. |
