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.

Abstract: Toner exhaustion is sensed in cartridge (1) having a toner chamber (3), a rotation paddle (7) extending across the long dimension. Chamber (3) has a transparent window (21) at its bottom and a reflective surface (23) in chamber (3), also at the bottom. An optical emitter and receiver (31) periodically senses for returned light, which indicates toner low. Paddle (7) carries a wiper to clean window and reflective surface. This provides improved accuracy by a cost-effective system.

Abstract: An article used to seal the interface between the developer roll, doctor blade and developer housing in a laser printer toner cartridge is described. The sealing member described in the present application performs static sealing between the components while the cartridge is idle and performs dynamic sealing while the toner cartridge is used for printing, keeping the sealing surfaces free from toner by actively pushing the toner back into the developer sump. The seal has a rotary seal portion which seals between the frame of the cartridge and the developer roll, and a blade seal portion which seals between the frame of the cartridge and the doctor blade. The rotary seal portion is biased toward the surface of the developer roll and incorporates, on its face adjacent to the developer roll, ridges which act to push the toner away from the edge of the developer roll in use. The blade seal portion is biased toward the doctor blade.

Abstract: An article used to seal the interface between the developer roll, doctor blade and developer housing in a laser printer toner cartridge is described. The sealing member described in the present application performs static sealing between the components while the cartridge is idle and performs dynamic sealing while the toner cartridge is used for printing, keeping the sealing surfaces free from toner by actively pushing the toner back into the developer sump. The seal comprises a rotary seal portion which seals between the frame of the cartridge and the developer roll, and a blade seal portion which seals between the frame of the cartridge and the doctor blade. The rotary seal portion is biased toward the surface of the developer roll and incorporates, on its face adjacent to the developer roll, ridges which act to push the toner away from the edge of the developer roll in use. The blade seal portion is biased toward the doctor blade.

Abstract: A toner cartridge for use in a laser printer has a toner reservoir or hopper in which a first paddle rotates about a fixed first axis to sweep most of the toner volume of the cartridge to agitate and push the toner out of the toner reservoir or hopper through an exit port. A second paddle is pivotally mounted on the first paddle to sweep a volume of the toner reservoir or hopper in which a portion of the longitudinal wall of the toner reservoir or hopper of the toner cartridge is non-circular so as to produce a reduced cross section in the toner reservoir or hopper. The second paddle also initially engages the curved portion of the inner surface of the longitudinal wall of the toner reservoir or hopper and preferably has a tear drop cross section.

Abstract: An encoded device for a toner cartridge provides a plate having preprogrammed indicia positioned at locations defined in relation to a clock face. The preprogrammed indicia includes a start indicia positioned at about a 6:00 o'clock position and at least one measurement indicia located between about 200 degrees and about 230 degrees from the 6:00 o'clock position.

Abstract: One aspect of the invention is the invention is directed to a toner cartridge including a sump for carrying a supply of toner. An agitator is rotatably mounted in the sump, and the agitator has a first end and a second end. An encoded wheel is coupled to the first end of the agitator. The encoder wheel is structured and adapted to include a first preselected cartridge characteristic indicia having a first extent, a stop indicia having a second extent larger than the first extent and a start indicia having a third extent larger than the second extent. Each indicia may be in the form of a slot. Preferably, the start indicia is positioned between about a 5:00 o'clock position and a 6:00 O'clock postition. The stop indicia is positioned at about a 9:00 o'clock position. At least one preselected cartridge characteristic indicia is positioned between the start indicia and the stop indicia.

Abstract: An encoded wheel for a toner cartridge including a plate having preprogrammed indicia positioned at locations defined in relation to a clock face, the preprogrammed indicia including a start indicia positioned between about a 5:00 o'clock position and a 6:00 o'clock position, a stop indicia positioned at about a 9:00 o'clock position, at least one preselected cartridge characteristic indicia positioned between the start indicia and the stop indicia, and at least one measurement indicia located between about 200 degrees and about 230 degrees from said 6:00 o'clock position.

Abstract: The weight of toner remaining at any time in a developer housing of a removable toner cartridge installed in a laser printer is determined by ascertaining the weight of the developer housing with the toner when printing is interrupted. The weight of the developer housing with the toner is ascertained through determining the magnitude of a rear reaction force on the side of the developer housing having the input for rotating a developer roll in the developer housing and then subtracting the weight of the developer housing from the weight of the developer housing with the toner. Next, the weight of the remaining toner is correlated to the determined rear reaction force. Then, the amount of the remaining toner is displayed to a user of the laser printer as a percentage of the initial total toner, either numerically or by a bar graph, for example.

Abstract: A toner cartridge has a comminuator that prevents the buildup of toner behind the doctor blade that meters the toner delivered to the developer roller for later image development and printing. The comminuator is mounted to, and for movement with, an agitator adjacent to an exit port of the toner hopper. A paddle that rotates within the toner hopper contacts the agitator and generates joint movement of the agitator and comminuator. The comminuator comprises a plurality of spaced blades held by a coupler mounted to the agitator. Alternatively, the comminuator comprises a wire mounted in opposing connectors mounted to the agitator.

Abstract: One aspect of the invention is directed to a toner cartridge including a sump for carrying a supply of toner. An agitator is rotatably mounted in the sump, and the agitator has a first end and a second end. An encoded wheel is coupled to the first end of the agitator. The encoded wheel is structured and adapted to include a first preselected cartridge characteristic indicia having a first extent, a stop indicia having a second extent larger than the first extent and a start indicia having a third extent larger than the second extent. Each indicia may be in the form of a slot. Preferably, the start indicia is positioned between about a 5:00 o'clock position and a 6:00 o'clock position. The stop indicia is positioned at about a 9:00 o'clock position. At least one preselected cartridge characteristic indicia is positioned between the start indicia and the stop indicia.

Abstract: A device within an image forming apparatus for positioning a doctor blade against a developer roller and preventing toner leakage. The device includes a developer housing for containing the developer roller and the doctor blade. A biasing member is positioned adjacent to the doctor blade for forcing the doctor blade against the developer roller for controlling the mass flow and charge level of the toner. The doctor blade is supported by retention stops on a front edge and a pair of supports on the back edge. Toner is prevented from leaking through the device by a flap seal positioned along the doctor blade back side and a seal positioned between each end of doctor blade end and developer housing. The invention provides for the doctor blade to be freely positioned between the retention stops, developer housing, and seals providing for the doctor blade to contact the developer roller in a consistent manner.

Abstract: Method is disclosed for determining characteristics of a toner cartridge. One aspect is directed to determining the characteristics associated with a quantity of toner in the cartridge, and thus, the method includes the steps directed to determining a home position of an encoded device relative to a code reader, determining a delay in rotational movement of the encoded device with respect to a rotational movement of a drive mechanism as an agitator moves through the toner, and translating the delay into an amount of toner remaining in the cartridge. Another aspect is directed to determining preselected cartridge characteristics from the encoded device, and thus, the method includes steps directed to rotating the encoded device, reading a coding of the encoded device, and decoding the coding to determine the preselected cartridge characteristic information represented by the coding. The method steps directed to these aspects of the method may be performed separately or in aggregate.

Abstract: An improved electrophotographic (EP) printer is provided having a detachable process cartridge that contains a non-volatile memory device, which is an EPROM that cannot be erased after a bit is burned. A "toner wheel" mounted to the exterior of the toner reservoir of the process cartridge provides, in conjunction with an optoelectronic sensor, an electrical signal that the printer receives and uses to determine toner usage. A toner "gas-gauge" is created which uses "bucket levels" as discrete steps to indicate how much of the measured physical toner material actually remains within the toner reservoir. After a given amount of toner material has been dispensed through the developer unit, one of the bits of the EPROM memory device is irreversibly burned, thereby providing a permanent record on the process cartridge of a certain amount of toner usage.

Abstract: A cartridge for an electrophotographic machine having a sump for carrying an agitator rotatably mounted in the sump for engagement with a toner; an encoded device coupled to a first end of the agitator; and a torque sensitive coupling connected to a second end of the agitator which is connectable to a drive mechanism of the machine. The encoded device includes coding representing cartridge characteristic information.

Abstract: An encoder plate, or wheel, is connected for rotation on a toner cartridge for an electrophotographic machine, wherein the encoder plate conveys cartridge characteristic information to the machine when the cartridge is installed in the machine. The encoder plate includes a plurality of openings, wherein an opened or closed status of the plurality of openings represent the cartridge characteristic information. Apparatus and method is provided to program the encoder plate by applying a material to the encoder plate to selectively cover one or more of the plurality of openings.

Abstract: Torsion springs (1) are graded by both winding and unwinding them in a test fixture (20) having a central arbor (52a) and ledges (54,58) functionally corresponding to the use of the springs. This takes hysteresis into account. Data obtained at a known location is approximated as separate straight lines for winding and unwinding. The rotation at the predetermined base or preload torque is determined from the straight lines, and the two values are averaged. To this average value a large predetermined amount (70 degrees) of rotation is added, the torque at that value of rotation is determined from the straight lines, and the two values are averaged. The spring is graded as acceptable when that average torque is within a predetermined range.