Abstract: A printing machine in which an endless web of sheet material is adapted to move along a path of movement. A recording device, in communication with the web of sheet material, prints information thereon. A fixing device, associated with the recording device, substantially permanently fixes the printed information to the web of sheet material. An inverter, positioned after the fixing device in the path of movement of the web of sheet material, inverts the sheet material enabling information to be printed on one side of the web of sheet material before inversion and information to be printed on the other side of the web of sheet material after inversion thereof.

Abstract: A toner cartridge is mounted movably on a developer unit of a printing machine. The toner cartridge stores a quantity of toner particles therein. A bar code is provided on the exterior surface of the toner cartridge. The bar code provides information concerning the toner particles within the housing. A bar code reader periodically detects the bar code and transmits information to a processing unit indicating the characteristics of the toner cartridge. This enables discrimination between different toner cartridges, ensuring that the proper toner cartridge is installed in the developer unit of the printing machine. In addition, the processing unit, in response to receiving a signal indicating that the bar code has been detected, provides a signal indicative of the quantity of toner particles remaining in the toner cartridge. This signal is transmitted to a graphical user interface which displays the remaining quantity of toner particles in the cartridge.

Abstract: A method of recording events in a printing machine having a plurality of subsystems. The recorded event corresponds to selected information generated as a result of an event occurring at one of the plurality of subsystems. The log event is communicated to a logging service. A log event file is created from the event information received at the logging service. The log event file is arranged in a file arrangement having a log event record. The log event file is translated to place the log event file in a readable output form.

Abstract: An apparatus for predicting a location of a sheet being transported along a path of movement after the occurrence of a sheet jam. A sheet jam detecting device is disposed along the path of movement of the sheet. The sheet jam detecting device detects the sheet jam along the path of movement and generates a sheet jam signal. A sensor is operatively associated with the transport to detect the continued movement of the transport after the jam detecting device detects the sheet jam. The sensor generates a transport signal. A processor is in communication with the jam detecting device and the sensor for receiving the sheet jam signal and the transport signal. The detector predicts the location of the sheet as a function of these signals. An apparatus of this type may be used in a printing machine for detecting the location of sheets after the occurrence of a sheet jam.

Abstract: An electrophotographic printing machine that has a photoconductive belt with a skewed seam thereon. The position of the skewed seam is detected by a pair of seam detection devices. The seam detection devices are spaced from one another and adapted to transmit a pair of signals with the signals having a time interval therebetween. These signals are inputted to a detection circuit and, if the time interval between signals is within a preselected tolerance, the detection circuit generates a seam indication signal. In this way, scratches on the photoconductive surface may be discriminated from the seam.

Abstract: A printing system including three print engines. One of the print engines is non-operational while the other two print engines are operational. The non-operational print engine is redundant and only actuated in the event that one of the operational print engines develops a malfunction causing it to be non-operational. At that time, the previously non-operational print engine becomes operational. In this way, two print engines are continually in operation with one print engine being non-operational. This printing system significantly improves reliability and minimizes maintenance requirements.

Abstract: A single pass, multi-color electrophotographic printing machine architecture uses a vertically oriented photoconductive belt. Transfer of the toner powder images occur at the lowermost portion of the photoconductive belt. The photoconductive belt is elliptically shaped, having a major and a minor axis. N image recording stations are positioned adjacent an exterior surface of the photoconductive belt on one side of the major axis thereof. N-1 image recording stations are positioned adjacent the exterior surface of the photoconductive belt on the other side of the major axis thereof. The image recording stations record electrostatic latent images on the photoconductive belt. This architecture optimizes image registration while minimizing the overall height of the printing machine.

Abstract: An apparatus which transfers a developed image from a photoconductive member to a sheet. A sheet baffle guides an advancing sheet to the photoconductive member at the transfer station. The sheet baffle has an elongated axis extending in a transverse direction to the planer surface of the photoconductive member. A sensing unit, located prior to the transfer station, generates a signal indicative of the sheet basis weight. A regulator, responsive to the signal from the sensing unit, adjusts the position of the sheet baffle to position the elongated axis thereof at a selected angle relative to the planer surface of the photoconductive member. This angle is greater for a lightweight sheet than for a heavyweight sheet.

Abstract: A commutating connector which electrically connects conductive paths of a rotating electroded donor roll to a voltage source. The connector includes a housing made of an electrically insulating material. The housing defines a chamber to receive the donor roll. An electrically conductive brush is disposed in the chamber. The brush is mounted in pressing engagement against the conductive paths on the electroded donor roll to electrically connect the voltage source to the conductive paths on the electroded donor roll. The chamber is divided by a partition into a commutating and a non-commutating area. The housing has ports for receiving air to prevent particulate matter from accumulating between the brush and donor roll.

Abstract: A sensing and a control system are disclosed for eliminating registration error during duplex printing in a multi-pass xerographic printing system. The system registers a common physical edge of a sheet using multiple pairs of sensors. During the first pass or simplex pass, a first set of sensors detect the leading edge of a sheet of paper, and during the second pass or duplex pass, a second set of sensors detect the trailing edge of a sheet of paper. The control system regulates the rate at which a sheet should be driven to be in timed registration with a developed image on a photoreceptor at a transfer station. Variations in sheet size due to sheet cut tolerances are eliminated by the sensing and the control system since any offset is directed towards a common physical edge when developed front and back images on a photoreceptor are registered with a sheet of paper.

Abstract: A method for adjusting image quality in a printing machine having a variable density image developed on a photoconductive surface in accordance with an initial set of starting values. The method includes a first layer of detecting a plurality of densities of the variable density image and transmitting a plurality of signals with each signal being indicative of a density; generating new starting values, responsive to the plurality of signals, using a linearized perturbation model; calculating error values, responsive to the plurality of signals, minimizing the sum of the squares of the error values; testing the error values for convergence on a set of reference values with each reference value indicative of an acceptable density; repeating the detecting, transmitting, generating, calculating, and testing steps for a plurality of iterations.

Abstract: An epicyclic drive train arrangement having a plurality of output drive members which may be selectively driven from a single input drive member. A frame equipped with two pawls is operated by a single solenoid and spring combination. During successive cycles of solenoid operation, a selected pawl engages its mating gear by action of a solenoid plunger rod. The action prevents rotation of the selected gear while the pawl is engaged. The unselected pawl disengages its mating gear thereby allowing it to freely rotate. Multiple epicyclic drive train arrangements may be configured so as to drive a plurality of sheet feeding apparatuses in an electrophotographic printing machine.

Abstract: An apparatus for maintaining an ambient condition about a marking module. The apparatus includes a substantially air impervious enclosure defining a chamber having the marking module disposed therein. An air flow source supplies air to the chamber, and sensors respond to the amount of air flow to control the air flowing from the air source.

Abstract: An apparatus which detects a mass of marking material developed on a test patch recorded on a photoconductive surface. The apparatus includes a densitometer, a capacitor sensor and a controller. The densitometer is spaced from and adjacent to the photoconductive surface. The capacitor sensor is also positioned adjacent to the photoconductive surface and spaced therefrom. In operation, the densitometer generates a first signal proportional to the specular component of the total reflectivity of the material deposited on the test patch developed on the photoconductive surface. The capacitor sensor generates a second signal proportional to the mass of material developed on the test patch recorded on the surface. In response to these signals, the controller generates a first control signal as a function of the first signal received from the densitometer in response to the mass of material deposited on the test patch being less than a preselected mass.

Abstract: A printing machine of the type having a plurality of components for printing a document is disclosed. The printing machine includes an air source and a support member having a component mounted thereon. The support member is coupled to the air source which has output ports so that air flows from the output ports.

Abstract: An apparatus in which a rotabably mounted donor roll advances toner to an electrostatic latent image recorded on a photoconductive surface. The donor roll has a plurality of conductive electrodes mounted thereon which rotate in unison therewith. A resistive disk is connected electrically to each of the conductive electrodes. The resistive disk also rotates in unison with the donor roll. An electrically conductive brush is in sliding contact with the resistive member. A voltage source, mounted stationarily, is coupled electrically to the resistive member. The voltage applied to each conductive electrode varies as a function of the distance between the voltage source and that conductive electrode.

Abstract: An apparatus for illuminating a photoconductive surface. The apparatus includes a housing defining a chamber and an open end. An imaging device is placed in the housing chamber. The imager transmits light rays through the open end of the housing to the photoconductive surface. An air pump is coupled to the housing. The air pump maintains an outwardly directed flow of air from the open end of the housing so as to move particles away from the open end. Electrically biased electrodes are located between the imaging device and the photoconductive surface. They attract the particles so as to prevent the particles from contaminating the imaging device.

Abstract: An imaging member having a substrate with a photoconductive layer coated thereon is anisotropic. The anisotropic substrate is stiff along one axis and flexible along another axis. Reinforcing fibers are aligned in the substrate to achieve the relative stiffness.

Abstract: An apparatus for replenishing toner in a developer unit has a plurality of toner discharge units. A selected discharge unit is energized to dispense toner into the developer unit with the other discharge units being de-energized. After the energized discharge unit is substantially depleted of toner, another toner discharge unit is energized. The depleted toner discharge unit is removed and replaced with a new toner discharge unit.

Abstract: A color electrophotographic printing machine in which latent images having a resolution of at least 1.44 million pixels per square inch are recorded on a photoconductive member. Different color toner powder images are developed in superimposed registration with one another to form a composite multicolor image. The composite multicolor image is transferred from the photoconductive member to a receiving member. Toner particles which have a selected pigmentation and small volume average diameters are used to minimize curl of the receiving member.