Abstract: Data may be obtained in the form of a printer control density table from a memory within a replacement toner cartridge. The cartridge may include parity bits to ensure the accuracy of the data.

Abstract: A printing device (10) such as a laser printer includes a fuser assembly (200) with a fuser wiper (210) that can be removed and replaced by a user during normal maintenance to extend the useful life of the fuser assembly (200). Indicators (b0, b1) stored in a memory device (144) can be read by a print engine (36) of a printer (10) either when a print cartridge (100) is first inserted into the printer (10) or at specified times thereafter. Depending on the contents of the memory device (144), the print engine (36) may send a notification message to the printer's raster image processor (150) to cause a message to be displayed on the printer's operational/display panel (254) that informs a user the fuser wiper (210) should be replaced.

Abstract: Toner transfer in an imaging device having a developer roller (5) that applies toner to a photoconductive roller 7 is determined by counting pels (38) and by counting operating cycles (56). Additionally in the embodiment, various device factors including darkness setting and type of toner are also applied to the totals. An adjustment factor, stored in a toner cartridge memory, is originally substantially one and may be adjusted based on subsequent knowledge or observations of the results. A page count of pages imaged is also used dependently as a second basis for amount of toner transferred.

Abstract: Toner usage is measured with good accuracy. Printing tends to darken with the depletion of toner from a source. A toner cartridge employed in a printer (70) has the capability at the cartridge of determining the amount toner used. In an embodiment this is by a torsion spring (60) drive to a toner paddle (3). At turn-on and cover open, the amount of toner is measured at the cartridge (80). That is stored in NVRAM (78) when it is very different from the current amount stored in NVRAM. At certain amount levels observed at the cartridge the amount in NVRAM is revised to the new amount. Between those levels the amount of toner used is tracked by counting pels (94). Use amounts are converted to operating factors in a table (100), and the operating factors are applied to the printer to keep the darkness of printing more constant. Writing to NVRAM is minimized.

Abstract: Toner hopper (1) of a printer (70) has a stirring paddle (3) with an encoder wheel (30, 50) mounted on paddle shaft (5). The drive connection to paddle (3) is through a torsion spring (60). Data processing apparatus determines paddle acceleration or deceleration (90, 94, 98, 102) and executes a table look-up to determine scaled amounts of subsequent movement (92, 96, 100, 104). Steady state movement is a unitary (unscaled) amount (106). These amounts are totaled (93) and used to define yield at the torsion spring, which corresponds to amount of toner in the hopper. This eliminates hardware in previous embodiments at the drive motor to signal actual rotation of the drive motor.