Abstract: Toner material is transferred from a locally charged imaging member to a printed material with a d.c. voltage applied onto an a.c. voltage having voltage peaks in the range of 6-8 kV with a duration of 0.5-1.5 &mgr;sec combined with it.

Abstract: Toner (5) is measured in a toner cartridge (1) by compressing the air in the upper part (7) of the toner hopper (3). The result of the compression is observed by a diaphragm (13) or, alternatively, by a pressure transducer (25). The volume of air is inversely proportional to the resonant frequency of diaphragm (13) or the pressure at pressure transducer (25). This is converted by control system (23) using direct equations or table look-up of empirical data. The diaphragm (13) carries a magnet (15), which is driven by coil (19) from the imaging device and then frequency of current induced by magnet (15) is then sensed by coil (19). Uneven toner piling is not a significant factor in the results measured.

Abstract: A fixing unit fixes a developing material deposited on a recording medium by heating and pressing the recording medium. The fixing unit includes a first number of heating members that apply heat to the recording medium and a second number of switches that supply electric power to the first number of heating members. Each of the heating members receives electric power through a series circuit of the switches. Each of the switches responds to a surface temperature of a corresponding one of the heating members so that when the surface temperature exceeds a predetermined value, the electric power is shut off.

Abstract: In a printing system in which a rotatable print image bearing belt is mounted on at least one axial belt roller, and the belt must be maintained in a desired substantially consistent lateral registration to maintain image quality, the lateral misregistration of the belt is sensed and a low and substantially constant lateral positional corrective force is applied to the belt in response to the sensing of the lateral misregistration in one of the two directions axial of the axial belt roller for at least one complete rotation of the rotatable print image bearing belt, the low and substantially constant transverse corrective force having a force level sufficient to provide the desired substantially consistent lateral registration of the print image bearing belt.

Abstract: In a method for forming an image, an electrification device electrifies an image bearing member to a predetermined potential. An exposure device exposes the electrified image bearing member. A potential detection device detects the potential of the electrified image bearing member and the image bearing member is re-electrified using the electrification device in accordance with a value obtained on the basis of the detected potential. The potential of the re-electrified image bearing member is detected. A value to be applied to the electrification device is determined on the basis of both the detected potential and the redetected potential when a difference between the redetected potential and a target value is great. An image is formed by electrifying the image bearing member in accordance with the determined value.

Abstract: In a printer in a system comprising multiple printers connected to a LAN, the service technician executes certain diagnostic adjustment through the operation of keys on the operation unit. When this is done, the controller of the printer generates a script that describes that the same service as indicated via the key input by the service technician in this diagnostic adjustment episode should be executed. The generated script is sent to the other printers. Each printer that receives the script automatically executes diagnostic adjustment based on the description of the script. As a result, the same diagnostic adjustment tasks as those executed regarding the printer from which the script was received is performed on each printer that received the script.

Abstract: A shutter device for protecting a photosensitive rotary drum includes a drum cover, at least one torsion spring, a press button, and a compression spring. The drum cover has a fixed end pivotally connected to a predetermined location of a process cartridge, a free end shielded on an exposed portion of said drum and an inside surface formed with a hook, and the torsion spring is arranged on said fixed end of the drum cover. The press button is received in a room of a side of the process cartridge, and the compression spring is positioned between a protruded rod formed inside said press button and a sleeve disposed on said room. Furthermore, the present invention has a better protection for the photosensitive rotary drum, and in the meanwhile, can be as a switch of an exposure window of the process cartridge.

Abstract: A single piece control grid electrode for a corona charging device for charging a curvilinear shaped dielectric support member with improved charging uniformity and consistency and with lower assembly and service cost. The single piece control grid is formed by a plurality of integral planar segments angularly oriented with respect to each other so that each segment may be equally spaced from the curvilinear shaped dielectric support member.

Abstract: A toner resupply roller in a laser printer has ribs that are not parallel to the rotational axis of the roller. The ribs form a tilted, helical, herringbone, or other pattern on the roller. The nonparallel ribs may serve to reduce vibrations introduced into the printer mechanism, and to distribute toner in such a way as to reduce banding in printed materials.