Hewlett-packard Company

Hewlett-packard Development Company, L.P.

Wayne E Foote

David J Arcaro

Kenneth Eugene Heath

Paul L Jeran

Paul K Mui

B Mark Hirst

Mark John Wibbels

C S Chan

Jeffrey Scott Weaver

Jeffrey C Madsen

Richard G Sevier

Roger Robert Sleger

Keng Leong Ng

Robert R Hay

Kenneth A Lindblom

Toh Tung Wong

Kyi Thu Maung

Thaddie Natalaray

Allen L Frazier

Richard L Swantner

Paul K Mul

Mark W Wright

Clifford K Day

An automatic document feeder with a drive system that can efficiently handle double-side scanning and accommodate more than one timing sequence for sequentially picking individual sheets from a stack using only two motors&#x2014;a pick motor and a media motor. The automatic document feeder includes a pickup unit with a pick roller, a set of de-skew rollers, a main media path configured to guide a media sheet from the pickup unit to a scanning region and from the scanning region to an output tray, and a switch-back path configured to guide the media sheet back into the main media path. The drive system is operable to provide a high-speed picking mode and a delayed picking mode. In the high-speed picking mode, the pickup unit is driven by the pick motor to pull a subsequent media sheet from a stack of media sheet as soon as a previously pulled media sheet has passed the pick roller. In the delayed picking mode, the de-skew rollers are driven by the pick motor to advance the media sheet toward the scanning region and the subsequent media sheet is pulled from the stack by the pickup unit when the previously pulled media sheet has passed the de-skewed rollers.

Automatic document feeder

An implementation of a technology is described herein for a fusing system comprising a heating assembly comprising a thermally self-regulating heating element.

Thermally self-regulating fusing system for thermal transfer overcoat device including stationary heating assembly

A paper drive sheet feeder system includes an edge guide, a paper transport mechanism, a paper edge detector, and control circuitry. The edge guide serves to guide the edges of a sheet of paper along a travel path of a peripheral device. The paper transport mechanism is configured to move the sheet of paper along the travel path. The paper edge detector is provided along the travel path to detect a leading edge of the sheet of paper. The control circuitry communicates with the paper transport mechanism and the paper edge detector and is operative to locate the sheet of paper in response to the detected leading edge of the sheet of paper along the travel path to accurately superpose successive image planes during a multiple color image transfer process. A printing system and a method are also provided.

Recirculating type paper drive for a direct transfer color printer

This invention relates to an improved heater bar that can be used for either a heater in a laser printer fuser or a heater in a thermal overcoat or laminating mechanism. The improved heater bar utilizes a positive temperature coefficient (PTC) thermistor element to produce the heat output.

Heater bar utilizing a positive temperature coefficient heating element

This invention relates to color printing, and more particularly, to color laser printing systems. Such structures of this type, generally, employ a rotatable, carousel type shuttle color printer with all in one electrophotographic (EP) cartridges which rotate to a non-printing position such that a predetermined gap or distance between the cartridges and the transfer belt is formed in order that the various colors required to be printed upon the sheet can be printed without adversely affecting the print quality.

Carousel type shuttle color printer with all in one EP cartridges

This invention relates to color printing, and more particularly, to color laser printing systems. Such structures of this type, generally, employ a rotatable, carousel type shuttle color printer with a plurality of toner reservoirs such that one of the plurality of toner reservoirs is a high capacity toner reservoir.

High capacity toner carousel type shuttle color printer with an all in one EP cartridge having reservoir

A print media sheet feeder system includes an edge guide grit belt to guide and move a sheet of media along a travel path of a peripheral device, and at least one pinch roller provided for co-rotation with the grit belt, wherein the sheet of media is moved between the belt and the roller along one edge.

Print media sheet feeder and printing system

A temperature differential over a length of a fuser can result from a thermal load applied to the fuser by media having a dimension, corresponding to a longitudinal axis of the fuser, less then the length of the fuser. The temperature on regions of the surface of the fuser contacting the media is lower than on regions of the surface not contacting the media. With feedback used to control the fuser surface temperature near its center, the fuser surface temperature in regions not contacting the media can become hot enough to damage the fuser. With a heat pipe included in the fuser, heat flows from the higher temperature regions on the surface of the fuser to the lower temperature regions on the surface of the fuser, thereby reducing the peak magnitude of the fuser surface temperature and the magnitude of the temperature differential over the length of the fuser.

Reducing a temperature differential in a fixing device

In a device including a replaceable cartridge containing a consumable material, the cartridge having at least one moving part, a system for estimating the use of consumable material from the cartridge is disclosed. The system includes an information storage medium secured to the moving part of the cartridge. A read-write head is mounted in the device in proximity with the information storage medium, and is adapted and constructed to write information on and read information from the information storage medium. The storage medium can be provided as a magnetic storage medium, which may be configured as an annular disc. The moving part can be provided as a generally cylindrical roller assembly including a drive gear. The drive gear can include an end surface to which the storage medium may be secured. The device itself can be any suitable printing device, such as a laser printer. The cartridge may be provided as a toner cartridge, in which instance the consumable material would be toner. In an embodiment, the storage medium may be secured to an Organic Photo Conductor ('OPC') roller. A method for estimating the use of consumable material from the cartridge is also disclosed, in which the read/write head is actuated to write cartridge use information on and read cartridge use information from the information storage medium in response to operation of the device.

Method and apparatus for toner level monitoring and motion sensing

A single pass color printer employs a band drive to move media sheets through plural developer stations. The band drive also provides motive power to drive, in common (via frictional engagement with their respective peripheries), all of the organic photoconductor (OPC) rollers that are present in plural developer stations that are arrayed along the media movement path. The use of the common band drive assures that the surface speeds of the OPC drums and media sheets are synchronized at their respective points of contact, thus eliminating much of the station to station variations due to differences in diameters and runout of the plural OPC rollers.

Synchronous band drive for an inline color printer

A print apparatus includes a photoconductor and a mechanical system for moving the photoconductor past a scan line exposure station. The print apparatus includes a signal generator for providing outputs indicative of the movement of the photoconductor. A first comparator produces a first position error signal that is derived from a difference between a reference signal and a position error signal output, such position error signal indicating that the position of the photoconductor differs from a predetermined print position that is determinable with respect to the reference signal. The print apparatus further includes a laser beam scanner and a beam detector for producing a scan position signal. A second comparator is responsive to the scan position signal and the position error signal from the first comparator to produce a beam deflection control signal that is applied to a beam deflector having a mirror attached to a piezoelectric bimorph crystal cantilever element. The beam deflector moves the laser beam in a direction which reduces the beam deflection control signal and position the laser scan at a position closer to a predetermined print position.

Laser printer with piezoelectric apparatus to reduce banding by

A system for controlling color plane image alignment in a multi-color, single pass laser printer achieves such alignment by imprinting of alignment marks directly on a belt which carries and/or drives media sheets past plural developer modules in a process direction. A pair of sensors are positioned adjacent the belt to enable a sensing of the alignment marks. A controller causes each of a plurality of developers to print a set of alignment marks on the belt, each set including plural marks that are positioned transverse to a print process direction. The controller, in response to the sensors' detecting the printed marks on the belt, determines times at which the marks pass beneath the sensors and, from such determined times, derives variations from expected sense times of the marks of each set. Thereafter, the controller adjusts data feed from color plane sub-images to one or more laser scanners in such a manner as to reduce color plane image misalignments.

Apparatus and method for obtaining color plane alignment in a single

A printing system for printing on a sheet of print media, the system including an electrophotographic printer operable to print on the sheet at a first print speed; and a color printer operable to print on the sheet of paper at a second print speed. The inkjet color printer includes a bidirectional sheet advancer operable to controllably move the sheet along an inkjet printer print path in either of first or second opposite directions, an inkjet pen carriage configured to support at least one inkjet pen and movable in a scan direction transverse to the inkjet printer print path for printing on the sheet, and a registration system operable to register a color image to be printed by the inkjet color printer relative to the black image printed by the electrophotographic printer. The registration system includes an optical sensor supported by the inkjet pen carriage for movement with the pen carriage along the scan direction.

Plane registration for monochrome and color printing systems

A print apparatus includes a photoconductor and a mechanical system for moving the photoconductor past a scan line exposure station. The print apparatus includes a test signal generator for providing outputs indicative of the movement of the photoconductor. A first comparator produces a first position error signal that is derived from a difference between a reference signal and a position error signal output, such position error signal indicating that the position of the photoconductor differs from a predetermined print position that is determinable with respect to the reference signal. The print apparatus further includes a laser beam scanner and a beam detector for producing a scan position signal. A second comparator is responsive to the scan position signal and the position error signal from the first comparator to produce a beam deflection control signal that is applied to a beam deflector. The beam deflector moves the laser beam in a direction which reduces the beam deflection control signal and position the laser scan at a position closer to a predetermined print position.

Laser printer with apparatus to reduce banding by servo adjustment of a

An 'L' shaped element having horizontal and vertical sections, is submerged in the liquid toner concentrate such that the horizontal section is totally submerged while the vertical section is submerged proportionally to an amount of the liquid toner concentrate. A voltage source is connected to the 'L' shaped element. A second element is placed in close proximity to the horizontal section of the 'L' shaped element and is also totally submerged in the liquid toner concentrate. Next, a third element is placed in close proximity to the vertical section of the 'L' shaped element. The current flowing from the horizontal section of the 'L' shaped element through the liquid toner concentrate to the second element is proportional to the concentration of solid. By measuring the current flowing from the vertical section of the 'L' shaped element through the liquid toner concentrate to the third element and dividing by the current in the second plate, the volume of the liquid toner concentrate can easily be calculated.

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Eagle, ID, United States of America

Wayne E Foote