Patents Assigned to Hewlett-Packard Co.
  • Patent number: 6476845
    Abstract: A method of controlling light emitting elements in an electrophotographic print head includes providing a predetermined number of pulse width modulators having different width output pulses, the predetermined number being less than the number of light emitting elements; selecting multiple light emitting elements for coupling to respective ones of the pulse width modulators; and coupling the multiple selected light emitting elements to the respective pulse width modulators. An electrophotographic printer includes a print head having a predetermined number of light emitting elements; a predetermined number of pulse width modulators having different width output pulses, the predetermined number being less than the number of light emitting elements; and logic circuitry configured to couple multiple light emitting elements to respective ones of the pulse width modulators.
    Type: Grant
    Filed: December 13, 2000
    Date of Patent: November 5, 2002
    Assignee: Hewlett-Packard Co.
    Inventor: David J. Luman
  • Patent number: 6476928
    Abstract: A printing system having a printhead assembly with an integrated distributive processor for providing localized control of internal printhead processor operations. These internal operations include thermal, energy, firing and timing aspects of the printhead. The printing system includes a controller, a power supply and the printhead assembly. The printhead assembly includes a memory device and distributive integrated processor with an ink driver head.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: November 5, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Michael J. Barbour, George H. Corrigan, III, Richard I. Klaus
  • Patent number: 6467410
    Abstract: In a printer, liquid ink is applied to a print medium as the medium is passed through the printer. A low pressure zone is generated along one surface of the print medium to hold a portion of the print medium substantially flat for a period of time during and after the liquid ink is applied to the print medium. By subjecting the portion of the print medium to the low pressure zone, cockling of the print medium is prevented.
    Type: Grant
    Filed: January 18, 2000
    Date of Patent: October 22, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Steve O Rasmussen, John D. Rhodes, Geoff Wotton
  • Patent number: 6467769
    Abstract: An output bin that uses gravity to urge the sheets into alignment along two edges and thereby help form a fully aligned stack. In one embodiment, the bin includes a first panel facing each sheet as the sheet is output from the printing device, the first panel having a top, a bottom and a side; a second panel disposed along the bottom of the first panel, the second panel tipped relative to a leading edge that leads each sheet out of the printing device; and a third panel disposed along the side of the first panel. Each sheet dispensed into the output bin slides over the first panel until a leading edge of the sheet contacts an upper portion of the second tipped panel. The sheet then tips in the direction of the third panel and rests with the leading edge supported by the second panel and a side edge supported by the third panel.
    Type: Grant
    Filed: March 22, 2001
    Date of Patent: October 22, 2002
    Assignee: Hewlett-Packard Co.
    Inventor: Roland Boss
  • Patent number: 6470387
    Abstract: A tool for locating a device on a network includes software for capturing information from the network or from devices on the network. The captured information includes user information relating to a user or users that use the device being located. The captured user information is cross referenced with a database having user location information. The user location information is then referenced to determine a physical location of the device. Typically, the physical location of the device is in the same general area as its users.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: October 22, 2002
    Assignee: Hewlett-Packard Co.
    Inventor: Todd A. Fischer
  • Patent number: 6464417
    Abstract: A multi-purpose, transmissive paper sensor includes a light beam projector and light detector having an analog output signal. Changes in the output signal from an open loop condition indicate the presences of at least one print medium being in the field-of-view of the sensor. Output signals indicative of print media leading edge, trailing edge, and number of sheets interrupting the light beam provide improved print media transport control for hard copy apparatus.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: October 15, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Joseph D. Barbera, Babak Honaryar, William T. Jennings, Pierre J. Kaiser, Kieran B. Kelly
  • Patent number: 6461066
    Abstract: A printer with a media feed apparatus has a media tray with a surface for supporting a stack of media sheets. A wave drive mechanism above the stack support surface has a media contact element operable to make contact with a top sheet of a media stack in the tray while moving in a feed direction to shift the top sheet in the feed direction. An encoder above the tray operates to detect motion of the top sheet. A controller may monitor the encoder to determine the speed of sheet motion, and set the speed of the wave drive mechanism to maintain the sheet motion above a threshold.
    Type: Grant
    Filed: November 29, 2000
    Date of Patent: October 8, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Richard A. Kelley, Bruce G. Johnson
  • Patent number: 6461196
    Abstract: Methods and apparatus for preventing damage to memory cards, memory card connectors, host electronics, and other electronic devices by only allowing intended electronic devices to mate with the connector for which it is intended and/or determining when an electronic device has been inserted into a connector upside down.
    Type: Grant
    Filed: March 9, 2001
    Date of Patent: October 8, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Arthur King Wilson, Vivian Wei Chow, George Craig Lysy
  • Patent number: 6460990
    Abstract: A non-warping heated platen uses tight controls in the axial direction between a planar heater used to heat print media passing thereacross and a rigid planar base to which it is coupled. A plurality of embodiments are described for coupling the heater and base.
    Type: Grant
    Filed: December 1, 2000
    Date of Patent: October 8, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Robert M. Yraceburu, Michel A. Riou, Robert J. Reichert, Geoff Wotton
  • Patent number: 6457709
    Abstract: A media transport belt assembly has a continuous belt encompassing two rollers supported on a frame. A tension mechanism biases the rollers apart to generate tension in the belt. The end of one roller moves in response to increased belt tension to skew the first roller with respect to the second roller. The roller end may be pivotally attached to a frame for movement in an arc, or may be otherwise constrained to displace the roller from the plane of the belt.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: October 1, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Jeffrey C. Madsen, Wade A. Powell
  • Patent number: 6460078
    Abstract: Apparatus is disclosed for automatically configuring network media connections of end node interfaces as well as node interfaces that operate as a hub, a switch or a repeater in a Local Area Network. The apparatus utilizes a pseudo-random sequencer to prevent lock step operation whereby the connections cannot be properly configured.
    Type: Grant
    Filed: October 18, 2000
    Date of Patent: October 1, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Daniel J. Dove, Bruce W. Melvin
  • Patent number: 6457707
    Abstract: An automatic document feeder for moving a stack of individual sheets from a stack loaded position to a single sheet separator in a document processing apparatus uses a gate comprised of a rotatable stack stop having a finger movable between a stack blocking position and a stack transmitting position. The stack stop is driven through a drag clutch from a single source of rotary power which also drives the conventional single sheet separator and other movable parts of the document processing apparatus. Presentation of the stack to the single sheet separator is thus automated since the operator of the document processing apparatus loads the document stack against the gate comprised of the automated stack stop to avoid operator loading of a stack directly to the nip of the single sheet separator and resultant mispicks and multipicks of sheets from the stack.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: October 1, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Steven Wayne Hendrix, Samuel Arthur Stodder
  • Patent number: 6457887
    Abstract: A wet-dye hard copy apparatus is provided with a vacuum transport for moving print media from and input, through a print zone, to an output. In order to reduce high frequency paper cockle, the print media is subjected to a post-printing predetermined bending while the print dye thereon is drying. In an alternative embodiment, a post-ejection bending heating step is added prior to ejecting a printed print medium to the apparatus output.
    Type: Grant
    Filed: October 3, 2000
    Date of Patent: October 1, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Geoff Wotton, Steve O. Rasmussen
  • Patent number: 6460136
    Abstract: The invention enables plural computers to initiate operation of respective operating systems through use of a shared operating system kernel. A system embodying the invention includes a central storage unit (e.g. a disk drive) that includes an operating system kernel, and plural computers, each computer including memory for holding an initiation boot code that enables initial startup of the respective computer upon a power up or a reset. A channel communication link provides circuit connections between the central storage unit and each of the plural computers. Each of the plural computers responds to a power-up or reset action by initiating operation of respective ones of the boot codes. Each boot code, after initiating preliminary operations, performs an access of the operating system kernel from the central storage unit via the channel communication circuit so as to enable a high speed load of the kernel to the respective computer memories.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: October 1, 2002
    Assignee: Hewlett-Packard Co.,
    Inventors: Gerhard Krohmer, Gary R. Ackaret
  • Patent number: 6454478
    Abstract: Predetermined geometric constructs reduce heat loss in a vacuum platen and assist in the reduction of paper cockle in ink-jet printing. A vacuum platen for supporting media during printing is provided with a plurality of heating elements and surfaces interspersed with vacuum ports. The heater elements are laid into surface channels of the platen such that an insulative gap separates the heaters from the main platen support structure. In an alternative embodiment, an insulative gasket is provided for the gap.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: September 24, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Geoff Wotton, Steve O. Rasmussen
  • Patent number: 6456802
    Abstract: Pixel counting and a single level toner sensor are used to identify the toner capacity of a toner cartridge. Pixel counting is used to estimate the remaining toner in a toner cartridge based on an assumed initial capacity. A toner sensor provides a signal indicating when the toner reaches a known level, e.g., 30 percent. The estimated remaining toner is compared to the known level of toner to determine if the assumed initial capacity was correct. The comparison may occur when the toner sensor signal is provided or if the estimated remaining toner falls below the predicted toner low signal level and a toner sensor signal is not provided. If the assumed initial capacity is incorrect, the difference between the estimated toner level and the known level is used to indicate the actual toner capacity of the toner cartridge. A look-up table can then be used to recalibrate the pixel counting so that an accurate estimate of the remaining toner may be performed for the remainder of the toner cartridge life.
    Type: Grant
    Filed: April 2, 2001
    Date of Patent: September 24, 2002
    Assignee: Hewlett-Packard Co.
    Inventor: Quintin T. Phillips
  • Patent number: 6456498
    Abstract: A CompactPCI-based computer system including a chassis and a mid-plane board. The mid-plane board forms bus circuitry, and is positioned between a front and back of the chassis. The chassis and the mid-plane board combine to define a plurality of CompactPCI form factor slots, including front slots and back slots. At least one of the front slots and at least one of the back slots are system slots configured to receive and provide independent bus connections for respective CompactPCI form factor system processor cards. In one preferred embodiment, the mid-plane board is configured to provide a bussed connector at a first front slot and at a second back slot, and a transition connection at a first back slot and a second front slot. With this one preferred embodiment, a one- or two-unit wide system processor card can be loaded into the first front slot, and another one- or two-unit wide system processor card can be loaded into the second back slot.
    Type: Grant
    Filed: August 7, 2001
    Date of Patent: September 24, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Thane M. Larson, Kirk Bresniker
  • Patent number: 6456597
    Abstract: A method for discovering addressing information within a network switch for an unknown MAC address received as a destination address of a packet. Where prior techniques flooded the network with the received packet, switch to switch protocols of the present invention reduce the volume of such overhead network traffic required to discover the addressing information. In particular, the present invention propagates query messages through network switches in a load balance domain (a group of switches cooperable in accordance with the protocols described herein). The query messages are propagated using a pruned broadcast tree to reduce the number of transmissions required to reach all switches in the load balance domain. The propagated query message eventual elicits a response from the device which owns the previously unknown destination address.
    Type: Grant
    Filed: January 11, 1999
    Date of Patent: September 24, 2002
    Assignee: Hewlett Packard Co.
    Inventor: Ballard C. Bare
  • Patent number: 6454393
    Abstract: A method for making an orifice plate. The orifice plate defines both orifices and connected chambers. The orifice plate is constructed to permit, in the same print head, one chamber (or orifice) to be deeper (as well as, if desired, wider and longer) than another chamber (or orifice) that may be next to the first chamber.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: September 24, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Chien-Hua Chen, Antonio Cruz-Uribe
  • Patent number: 6454474
    Abstract: A simple, yet accurate way of determining calibration values for correcting the characteristic sinusoidal feed errors of a printer or other recording device (such as a fax machine, plotter, etc.). A sheet of calibration media is employed for facilitating the calculation of the calibration values. The sheet is used in a way that prevents the calibration media errors from affecting the calculation. In particular, the sheet of calibration media is fed twice through the printer, and position data is collected each time. The data is processed in a way that cancels the attendant calibration media errors so that the calculated calibration values precisely correct the characteristic sinusoidal feed errors of that printer.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: September 24, 2002
    Assignee: Hewlett-Packard Co.
    Inventors: Christopher M. Lesniak, Algird M. Gudaitis