Abstract: A modular duplex media handling system is installable for use with a print recording system having a simplex media handling system. During first side printing a media sheet is fed along a first media path in the simplex system from feed rollers to metering rollers and into a print zone. After first side printing and prior to releasing the media sheet, the metering rollers feed the media sheet back along the first media path to the feed rollers. The feed rollers in turn feed the media sheet completely into the duplex module where the media moves along a loop path (in effect flipping the media sheet). The media sheet then is fed back to the feed rollers and along the first media path for second side printing. A humidity sensor in the duplex module signals to the print recording system whether the duplex handling system is installed.

Abstract: A modular duplex media handling system is installable for use with a print recording system having a simplex media handling system. During first side printing a media sheet is fed along a first media path in the simplex system from feed rollers to metering rollers and into a print zone. After first side printing and prior to releasing the media sheet, the metering rollers feed the media sheet back along the first media path to the feed rollers. The feed rollers in turn feed the media sheet completely into the duplex module where the media moves along a loop path (in effect flipping the media sheet). The media sheet then is fed back to the feed rollers and along the first media path for second side printing. A humidity sensor in the duplex module signals to the print recording system whether the duplex handling system is installed.

Abstract: A sheet media handling system is provided for use in supporting a sheet ejected from a wet-ink hard copy apparatus output port while ink on a preceding sheet ink an output tray is allowed time to dry before depositing the succeeding on top thereof. The system employs a pair of guides having an elongate channel therebetween which receives a predetermined side edge of an ejected sheet. The channel bends the sheet in order to stiffen the sheet along its longitudinal axis such that only one edge need be supported. Once a trailing edge of an advancing sheet is ejected from the output port, a lower guide is retracted whereby the sheet falls under the force of gravity onto the output media stack in the output tray. Several advantageous lower guide upper surface constructs are disclosed. The advantages of the use of a guide mechanism on each side of the advancing output sheets is discussed.

Abstract: A media handling system includes a drive roller, an elongated pinch roller and a contoured support. The pinch roller extends across the print medium near the print zone to control the localized shape of the print medium. The support underlies the print medium in the print zone and includes first and second underlying pivotal inclines. The pinch rollers push the print medium onto the first pivotal incline adjacent to the drive roller. The second underlying incline is located downstream toward the print zone exit. As the print medium is fed through the print zone, a portion of the print medium within the print zone between the pivotal inclines is suspended exhibiting a reverse bowing. Beyond the second pivotal incline the print medium droops. The presence of the two underlying inclines more uniformly distributes the stress accompanying the bowing of the print medium within the print zone.

Abstract: A method and apparatus for effecting a digital communications in a tandem cross-connect of an intermediate station in a telephone system communications network to enable synchronization of the digital signals coupled between ports of the cross-connect. The method and apparatus provide center-tapped transformers at each port for coupling into the cross-connect, applying synchronizing signals to the center-tap of the transformer for raising and lowering the DC voltage of the transformer output cross-connect side without adversely affecting the signals being transmitted across the transformer coupled network, and processing received signals to identify and synchronize to repeating protocol patterns. In particular, the invention employs photo-optically coupling to the transformers to maintain electrical isolation of the synchronizing elements of the circuitry and employing the circuitry in particular in connection with synchronizing to the A and B signalling bits of a T1 protocol.

Abstract: A method and apparatus monitor the performance of a DDS loop connecting an information transmitter to an information receiver. The information transmitter is typically at a customer premises while the receiver is typically an OCU at the receiving local office. The DDS loop uses an alternate mark inversion communications protocol and the monitoring method and apparatus feature circuitry for determining a current imbalance on the DDS loop. The numbers of positive and negative pulses on the line are individually counted and if the count of the two counters used deviates either positively or negatively from each other by specified amounts, an error event is declared. If the error events meet a statistical timing criterion, a channel error is declared and appropriate steps are undertaken to prevent signals coming from the channel from interfering with other signals available at the local office.

Abstract: A method and apparatus for advancing a sheet of print media through a printer mechanism having a print zone. The apparatus includes a roller assembly for advancing a sheet of media through the print zone, a printing assembly for recording information on a surface of the sheet of media and an assembly for receiving the sheet of media once information has been recorded on the sheet of media. The apparatus includes a kicker which is movable in the forward direction to engage an edge of the sheet of media to urge the sheet in a forwardly direction from the print zone to the receiving assembly. The method of this invention includes the step of pushing the edge of the sheet of media towards the receiving assembly.

Abstract: Described herein is a printer having a printhead which traverses laterally across a sheetlike print medium and which thereby defines a laterally-extending print zone across the print medium. A paper transport mechanism in the printer has drive rollers and associated pinch wheels to drive the print medium through the printer's print zone. The paper transport mechanism further includes an upper print media guide and a lower print medium guide. The two print medium guides are shaped at their transverse ends to bow the transverse edges of the print medium downwardly to reduce its tendency to buckle upwardly into the printhead. In order to fit the upper print medium guide into the limited available space above the drive rollers, it is made of a lower molded portion for paper contact and an upper backing portion for rigidity. A pinch finger extends toward the printer's print zone beyond the pinch wheels to establish a pinch point against the drive roller in near proximity to the print zone.

Abstract: Described herein is a printer having a printhead which traverses laterally across a sheetlike print medium and which thereby defines a laterally-extending print zone across the print medium. A paper transport mechanism in the printer has drive rollers and associated pinch wheels to drive the print medium through the printer's print zone. The paper transport mechanism further includes an upper print media guide and a lower print medium guide. The two print medium guides are shaped at their transverse ends to bow the transverse edges of the print medium downwardly to reduce its tendency to buckle upwardly into the printhead. In order to fit the upper print medium guide into the limited available space above the drive rollers, it is made of a lower molded portion for paper contact and an upper backing portion for rigidity. A pinch finger extends toward the printer's print zone beyond the pinch wheels to establish a pinch point against the drive roller in near proximity to the print zone.

Abstract: A method for correcting the skew between the leading edge of a sheet of paper and the nip of a roller assembly in a printing mechanism includes the steps of advancing a sheet of paper into the nip and slightly therebeyond. The rollers are then rotated in reverse, causing the paper to retract from the roller assembly, with the angle and weight of the paper maintaining the leading edge within the nip. As the rollers continue to rotate backwards, the paper jiggles or dances allowing the leading edge to settle parallel with the nip under its own weight. The paper is then readvanced through the roller assembly with its leading edge parallel to the nip. A mechanism applies a drag force to the paper when the paper is being retracted from the roller assembly to keep the leading edge of the paper in the nip.

Abstract: An apparatus for control of a sheet of paper in a printer mechanism includes a single motor drive mechanism, a frame, a platen, a roller assembly for advancing the sheet of paper over the platen, and a kicker element for selectively contacting only an edge of a sheet of paper and for urging the sheet of paper in a forward direction once it is forwardly disengaged from the roller assembly.

Abstract: An improved paper feed arrangement wherein a low vertical profile is attained through utilizing trained driven belts for picking paper from a hopper, and wherein picking reliability is enhanced both by the broad-expanse area contact offered by such belts, and by a unique coefficient to friction differential area downstream from a hopper wherein inadvertently plural picked paper sheets are easily separated.

Abstract: A printhead cartridge and carriage assembly (10) is provided comprising: a carriage (12); a snap-spring (62) for securing a printing cartridge (14) in postion on the carriage; and an interconnect strip (16) for supplying electrical signals to the cartridge, including a force loading spring pad (24) for urging a portion of the interconnect strip against a portion of the cartridge. The cartridge has top (32), bottom (34), sides (36, 38), front (40) and rear (42) surfaces and includes a printhead (44) on the bottom surface, an electrical contact strip (46) on the back surface connected to the printhead, referencing pads (56) on the side surface, and a lip (64) on the back surface for accepting the snap-spring. Referencing surface (60) are provided for receiving the referencing pads on the cartridge. The spring pad urges the interconnect strip against the electrical contact of the cartridge.

Abstract: A novel ink-jet printer (10) is provided. The print provides both paper supply tray (12) and paper collection tray (18) in the front (14) of the printer for ease of paper handling and reduced footprint. The paper collection tray is provided with a pair of opposed output rails (22) which support a sheet of paper (16c) during printing to permit ink on a sheet of paper (16b) previously printed to dry. A paper handling mechanism is provided which eliminates a sheet pickup motor and associated elements. The paper handling mechanism is configured to pick off a sheet of paper from a stack of input paper, bring it around paper drive rollers (24) onto a platen (26), where the printing operation, employing a printhead cartridge (32), occurs. The printer further includes a service station (230) for clearing clogged nozzles in the printhead (33) and removing bubbles therefrom, for covering the nozzles with a protective cap (266), and for wiping contaminants off the nozzles.

Abstract: Several problems of alignment associated with ink-jet printers are alleviated by four aspects. In the first, a reverse bow (B) in the paper (12) is created for printing on single sheets of paper. The reverse bow, which in the transverse axis of the paper, forces the paper flat against the platen (14) by using the paper's own stiffness.In the second aspect, the paper and the carriage (30) are referenced to the same part (the carriage guide (10)). In this configuration, the paper is urged against the underside of the carriage guide off of drive rollers (18), through the reverse bow, and onto the platen, where it is printed. The carriage is referenced to the carriage guide through a slider bump by means of a carriage shaft and gravity.The carraige guide comprises stiff thin sheet metal, which is closely-toleranced and has well-controlled dimensions. Thus, this part is good to reference to, rather than molded-in parts, which are not stiff enough at the required thickness.

Abstract: An active paper drop mechanism (20) for ink-jet printers is provided. The mechanism comprises a pair of opposed, movable rail members (22) associated with opposed walls (14) of a horizontal-disposed output collection tray (12) for receiving sheets (10) of printed media.In particular, each rail member is provided with return spring (26) that act to maintain the rails in a closed position. In that position, the rails support a sheet of the print medium during the printing operation, thus giving the ink on the previously printed-on sheet (10') time to dry.The rails are provided with a wing member (32) and are pivotally secured (38) in the floor of the output tray, with the pivot point spaced inwardly from the wing member. Downward pressure against the wing member thus causes the rail to rotate outward from its closed position, into a recess (24) provided in the side of the output tray. This provides sufficient clearance for the sheet to drop into the output stack.

Abstract: A digital subscriber loop termination device, such as an office channel unit, dataport unit, digital data bank unit or the like, employs a microprocessor for providing data transfer between customer lines and network lines operating at respective different data transmission rates. The microprocessor circuit responds to network sync pulses for providing transfer of network input bytes to customer output generators and for providing for transfer of customer input bytes to network output serial generators. Additionally, the circuit includes facilities for enabling operation at different customer rates.

Abstract: A novel ink-jet printer (10) is provided. The printer provides both paper supply tray (12) and paper collection tray (18) in the front (14) of the printer for ease of paper handling and reduced footprint. The paper collection tray is provided with a pair of opposed output rails (22) which support a sheet of paper (16c) during printing to permit ink on a sheet of paper (16b) previously printed to dry.A paper handling mechanism is provided which eliminates a sheet pickup motor and associated elements. The paper handling mechanism is configured to pick off a sheet of paper from a stack of input paper, bring it around paper drive rollers (24) onto a platen (26), where the printing operation, employing a printhead cartridge (32) occurs.The resulting printer is easy to manufacture, has reduced complexity by eliminating components in the paper drive mechanism and is lower in cost.