Abstract: A characterization procedure for the a detector in a toner patch sensor of an electrophotographic image forming device is performed with the toner patch sensor operatively connected to the image forming device's power supply. During the characterization procedure, a gain setting is determined that produces a predetermined target output from the toner patch sensor based on electromagnetic radiation reflected from a reference reflectivity sample. Subsequently, a toner patch is generated by the image forming device and a reflectance of the toner patch is measured based on the gain setting, with the toner patch sensor operatively connected to the power supply. The measurement(s) may then be used to adjust at least one electrophotographic image forming parameter. More than one reference reflectivity sample may be used, with corresponding gain settings stored in the image forming device.

Abstract: Methods and devices for operating a toner patch sensor in an electrophotographic image forming device. A characterization procedure for a light detector in the toner patch sensor may use one or multiple reflectance standards. A gain setting is determined that produces a predetermined target output from the toner patch sensing circuit for each of the standards. The characterization procedure may be carried out at a test bench or with the toner patch sensor installed in the corresponding device.

Abstract: A method and device for monitoring toner transfer within an image forming device is described herein. A reflectivity sensor senses movement of a toner transfer gear operatively connected to a toner transfer system. A threshold unit generates a dynamic threshold based on the output of the reflectivity sensor. In one embodiment, the threshold unit generates the dynamic threshold based on a time delayed average of the sensor output. An instantaneous sensor output is compared to the dynamic threshold. Based on the comparison, the device determines the how much the toner transfer gear has rotated, and therefore, how much toner has been transferred from the toner cartridge.

Abstract: Methods and devices for operating a toner patch sensor in an electrophotographic image forming device. A characterization procedure for a light detector in the toner patch sensor may use one or multiple reflectance standards. A gain setting is determined that produces a predetermined target output from the toner patch sensing circuit for each of the standards. The characterization procedure may be carried out at a test bench or with the toner patch sensor installed in the corresponding device.

Abstract: A characterization procedure for the a detector in a toner patch sensor of an electrophotographic image forming device is performed with the toner patch sensor operatively connected to the image forming device's power supply. During the characterization procedure, a gain setting is determined that produces a predetermined target output from the toner patch sensor based on electromagnetic radiation reflected from a reference reflectivity sample. Subsequently, a toner patch is generated by the image forming device and a reflectance of the toner patch is measured based on the gain setting, with the toner patch sensor operatively connected to the power supply. The measurement(s) may then be used to adjust at least one electrophotographic image forming parameter. More than one reference reflectivity sample may be used, with corresponding gain settings stored in the image forming device.

Abstract: A method and device for monitoring toner transfer within an image forming device is described herein. A reflectivity sensor senses movement of a toner transfer gear operatively connected to a toner transfer system. A threshold unit generates a dynamic threshold based on the output of the reflectivity sensor. In one embodiment, the threshold unit generates the dynamic threshold based on a time delayed average of the sensor output. An instantaneous sensor output is compared to the dynamic threshold. Based on the comparison, the device determines the how much the toner transfer gear has rotated, and therefore, how much toner has been transferred from the toner cartridge.

Abstract: A media sensor for an image forming apparatus is operative to sense and distinguish opaque, transparent or no media in a media path. In one embodiment, an optical source and detector are positioned on opposite sides of the media path, at an acute, non-zero angle with respect to a direction normal to the media path. In other embodiments, an optical source and detector are co-located on the same side of the media path with an optical barrier between them, and one or more reflective surfaces positioned on the opposite side. With no media in the media path, the detector receives a readily detectable amount of optical energy emitted by the source. For opaque media, the detector receives very little, if any, optical energy emitted by the source. For transparent media, the detector receives a level of optical energy between that in the cases of opaque media and no media.

Abstract: Waste toner is detected in a container of an image forming apparatus. An auger is provided within the container. A switch is provided which is operable depending upon a torque associated with operation of the auger. A frequency of activation of the switch is detected. A “not full”, “near full” and “full” condition of the waste toner in the container is determined depending upon the frequency of activation of the switch.

Abstract: A motion control system for controlling the motion of an intermediate transfer member in an image forming apparatus is provided in which a measuring member directly contacts the intermediate transfer member and generates signals proportional to the surface motion of the member. The measured surface motion is provided as a feedback signal to a motor controller, which compares the feedback signal with a reference signal. The difference between the signals is used to adjust the control of the drive motor for the intermediate transfer member drive roller in order to maintain a constant velocity for the intermediate transfer member.

Abstract: Waste toner is detected in a container of an image forming apparatus. An auger is provided within the container. A switch is provided which is operable depending upon a torque associated with operation of the auger. A frequency of activation of the switch is detected. A “not full”, “near full” and “full” condition of the waste toner in the container is determined depending upon the frequency of activation of the switch.

Abstract: A method of activating an electrophotographic machine includes determining at least one condition of the electrophotographic machine. Power is applied to a polygon mirror. A time period required for the polygon mirror to accelerate from a stationary condition to a target rotational velocity is measured. The measured time period and data associated with the at least one condition are stored in a memory device. The polygon mirror is decelerated back to the stationary condition. Power is reapplied to the polygon mirror at a point in time. The measured time period and the data are used to determine when to begin at least one process in the electrophotographic machine relative to the point in time.

Abstract: A motion control system for controlling the motion of an intermediate transfer member in an image forming apparatus is provided in which a measuring member directly contacts the intermediate transfer member and generates signals proportional to the surface motion of the member. The measured surface motion is provided as a feedback signal to a motor controller, which compares the feedback signal with a reference signal. The difference between the signals is used to adjust the control of the drive motor for the intermediate transfer member drive roller in order to maintain a constant velocity for the intermediate transfer member.

Abstract: A method of aligning print images of an electrophotographic machine on a print medium includes reflecting a first laser beam off of a first rotating reflector to thereby scan the first laser beam across a first photoconductive drum to produce a first scan line in a scan direction. The rotation of the first reflector is cyclically repeated to thereby produce a plurality of substantially parallel first scan lines on the first photoconductive drum. A respective line of first toner is applied to each of the first scan lines. A second laser beam is reflected off of a second rotating reflector to thereby scan the second laser beam across a second photoconductive drum to produce a second scan line in the scan direction. The rotation of the second reflector is cyclically repeated to thereby produce a plurality of substantially parallel second scan lines on the second photoconductive drum. A respective line of second toner is applied to each of the second scan lines.

Abstract: A method of aligning print images of an electrophotographic machine on a print medium includes providing a plurality of rotating photoconductive drums in the electrophotographic machine. Each of a plurality of laser beams is reflected off of a respective one of a plurality of reflectors. Each reflector rotates relative to the respective laser beam to thereby scan the laser beam across a respective one of the photoconductive drums to produce a scan line in a scan direction. The relative rotation between the laser beams and the respective reflectors is cyclically repeated to thereby produce a plurality of substantially parallel scan lines on each photoconductive drum. Each scan line is displaced from an adjacent scan line by a scan line separation distance in a process direction perpendicular to the scan direction. Toner is applied to each scan line on the photoconductive drums. A moving toner transfer medium contacts each photoconductive drum at a respective toner transfer nip.

Abstract: An electrophotographic image forming apparatus transfers image information relating to an image to be formed on a medium, while maintaining desired low levels of electromagnetic emissions. The apparatus includes an image processor that generates low-frequency image information signals containing the image information. A low-frequency interface is connected to the image processor for transferring the low-frequency image information signals. A control circuit, connected to the low-frequency interface, receives the low-frequency image information signals generated by the image processor. The control circuit operates on the low-frequency image information signals to form a high-frequency image information signal therefrom, where the high-frequency image information signal contains the image information. The apparatus also includes a high-frequency interface connected to the printhead control circuit for transferring the high-frequency image information signal.

Abstract: Toner is conserved in printer (1) under operator control by changing the final modulation for each bit in a bit map depending on whether the bit is an edge bit or an internal bit in the character being printed. Since only the final modulation is affected, processing speed and efficiency are not degraded. The operator can select various degrees of internal gray and internal white. Some levels of gray may be satisfactory for some final correspondence.

Abstract: An ASIC (5) has four driver circuits (19a-19d), each with different output power. One of those driver circuits is selected from the content of register (13) on the ASIC. The register content being decoded by a decoder (15) on the ASIC to a signal which activates a single one of the drivers. The register is loaded from an external microprocessor during each initialization of a printer (1) in which the ASIC is a component. The ASIC is designed with the range of the powers of the drivers bracketing the estimated needs of the load to be attached to the ASIC. This permits the ASIC to be completed only once, while the most suitable driver for the final load is determined subsequently and selected by the entry of data to activate that driver into the register with each initialization of the printer. The ASIC need not have nonvolatile memory and only a single set of ASIC masks and other design aspects need be completed.

Abstract: Toner is conserved in printer (1) under operator control by changing the final modulation for each bit in a bit map depending on whether the bit is an edge bit or an internal bit in the character being printed. Since only the final modulation is affected, processing speed and efficiency are not degraded. The operator can select various degrees of internal gray and internal white. Some levels of gray may be satisfactory for some final correspondence.

Abstract: An electrophotographic printer (1) adjusts high resolution data while preserving the resolution capabilities of the printer. Data in a 600.times.600 bit map is assigned alternately to two rows of a 300.times.1200 bit map. Excellent visual effects are realized.