摘要 |
An apparatus and method are disclosed for measuring the quantity of residual toner contained in a toner cartridge, and an image forming apparatus having such a device. The inventive device for measuring the quantity of residual toner comprises a controller and a residual toner data memory. The controller selects one of a plurality of preset values for one or more correction coefficients weighted depending on the length of time the toner cartridge has been in printing service, and calculates the quantity of residual toner using the selected value for each correction coefficient and the number of counted dots of a print data. The residual toner memory stores the quantity of residual toner calculated and updated by the controller. According to one exemplary embodiment, the quantity of residual toner can be calculated close to actual value by applying appropriately weighted coefficients. |