Abstract: A toner level detector includes a toner cartridge, an agitator, a reflective region, a first cleaner, a second cleaner and a transceiver. The toner cartridge stores toner, and has a light-permeable region. The agitator rotatably disposed in the toner cartridge agitates the toner. The reflective region is disposed on the agitator. The first cleaner is disposed on the agitator. The second cleaner is disposed on the toner cartridge. The transceiver disposed on a body outside the toner cartridge outputs an emitting signal to the reflective region through the light-permeable region. The reflective region reflects the emitting signal to generate a reflective signal received by the transceiver through the reflective region. The rotating first cleaner intermittently cleans the fixed light-permeable region, and the fixed second cleaner intermittently cleans the rotating reflective region.

Abstract: A toner maintenance system for an electrophotographic developer unit, including a sump for storing a quantity of developer material comprised of toner material; a first member for transporting developer material from the sump, a viewing window, in communication with toner material, in the sump; an optical sensor, for measuring reflected light off the viewing window and toner material, and generating a signal indicative thereof. A toner concentration controller is adapted to receive a signal from the optical sensor and to generate an “Add Toner” signal to replenish toner material in the sump.

Abstract: A developer container for containing a developer includes a detecting member for detecting a developer amount having an electrode member having a pair of input-side and output-side electrodes formed in parallel and in one plane at a predetermined interval and adapted to detect the capacitance between the electrodes, a measurement-side electrode that is in contact with the developer, and a reference electrode that is out of contact with the developer, the detecting member being provided on a side surface of the developer container. The container also includes a developer removing member for removing developer adhering to a detection surface of the detecting member, the developer removing member being attached to the developer conveying member and in contact with the detection surface of the detecting member so as to remove developer on the detection surface of the detecting member.

Abstract: A control apparatus for controlling a concentration of a solute having a predetermined optical absorption characteristic is disclosed. A cell holding member has a plurality of cells formed therein, one of which is placed at a predetermined detection position so that the solution flows through that cell. A concentration of the solute is detected based on the intensity of light that has passed through the cell placed at the predetermined detection position. A cell changer replaces the cell with another cell by moving the cell holding member when a detected concentration has not changed as expected.

Abstract: A developer concentration detection apparatus is provided, which includes a base member in which a developer accommodation space is formed, an electrode plate member installed in the base member so that a toner included in a developer in the developer accommodation space is electrically charged, a hollow transparent conductive tube which is rotatably supported in the state where at least part thereof is submerged in the developer in the developer accommodation space and the surface thereof can be charged, a light emitting element installed in the transparent conductive tube, and a light receiving element installed spaced from the surface of the transparent conductive tube, for detecting light generated from the light emitting element. The developer concentration detection apparatus can detect measurement of the developer concentration, thereby providing the result of assuring an optimal printing quality.

Abstract: A device for measuring toner concentration of developer housed in a developing system, which developer comprising toner and carrier. The device has a transparent detection window facing the interior of the developing system, which transparent detection window comprising a first transparent plate member and a second transparent plate member being in contact with the first transparent plate member. The first transparent plate member is made of a material which becomes charged, through its contact with the second transparent plate member, with the opposite polarity from the charge polarity of the toner and the second transparent plate member is made of a material which becomes charged, through its contact with the carrier, with the same polarity from the charge polarity of the toner, so that the second transparent plate member strongly repels the toner having the same polarity charge and adherence of the toner to the second transparent plate member is reliably prevented.

Abstract: A toner level detecting device on a toner fillable box includes first and second toner detecting portions formed of a light transmissive material and a toner fillable aperture formed between the first and second toner detecting portions, wherein the toner fillable aperture has a non-uniform width. The toner fillable aperture is cleaned using a cleaning blade mounted to rotate within the toner fillable aperture to clean toner from the inside surfaces thereof, thereby providing more accurate toner level detection. The toner fillable aperture is a generally V-shaped or U-shaped member having smooth transitions such that toner does not collect or accumulate in corners where a cleaning blade cannot reach after possible being deformed during use. Furthermore, the material of at least a portion of the toner fillable aperture and/or the toner detecting portions is formed of a semi-transparent material that absorbs latent light that might otherwise cause inaccurate toner level measurement.