Patents by Inventor Ross W. Johnston

Ross W. Johnston has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6798221
    Abstract: A fuel cell resistance test system includes a contact head having a plurality of spaced electrical contacts for contacting multiple ones of the fuel cells composing the stack. In one embodiment, a plurality of selectively actuable switches produce a short between respective pairs of adjacent ones of the electrical contacts. A processor opens each of the switches, one at a time in succession, to apply a defined voltage from a voltage source, successively across pairs of adjacent ones of the electrical contacts. A current sensor measures a resulting current and the processor or other computer determines whether a short exists based on the magnitude of the defined voltage and the magnitude of the resulting current. Alternatively, the test system may include a current source and a voltage sensor.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: September 28, 2004
    Assignee: Ballard Power Systems Inc.
    Inventors: Zhaoyu Wang, Ross W. Johnston Bailey, Graham E. Hill, Hong The Nguyen
  • Publication number: 20030076110
    Abstract: A fuel cell resistance test system includes a contact head having a plurality of spaced electrical contacts for contacting multiple ones of the fuel cells composing the stack. In one embodiment, a plurality of selectively actuable switches produce a short between respective pairs of adjacent ones of the electrical contacts. A processor opens each of the switches, one at a time in succession, to apply a defined voltage from a voltage source, successively across pairs of adjacent ones of the electrical contacts. A current sensor measures a resulting current and the processor or other computer determines whether a short exists based on the magnitude of the defined voltage and the magnitude of the resulting current. Alternatively, the test system may include a current source and a voltage sensor.
    Type: Application
    Filed: February 14, 2002
    Publication date: April 24, 2003
    Applicant: Ballard Power Systems Inc.
    Inventors: Zhaoyu Wang, Ross W. Johnston Bailey, Graham E. Hill, Hong The Nguyen
  • Patent number: 5406425
    Abstract: The present invention provides a complete digital data storage (DDS) magnetic tape system for utilization with a host unit. The invention comprises a host device interface for interfacing the host unit with the DDS system, a controller/formatter for encoding and decoding data from and to the magnetic tape, an automatic track follower (ATF) for performing automatic track following on the magnetic tape, a driver for driving the magnetic tape, a read/write (R/W) channel for channeling data thereto and therefrom, a read/write (R/W) head drum for transferring data to and from the magnetic tape, and the controller/formatter, the ATF, the driver, the R/W channel, and the R/W head drum all being under software programmable control.
    Type: Grant
    Filed: July 1, 1992
    Date of Patent: April 11, 1995
    Assignee: R-Byte, Inc.
    Inventors: Ross W. Johnston, Theodore D. Rees, Edward J. Rhodes
  • Patent number: 5287478
    Abstract: A complete digital data storage magnetic tape system for utilization with a host unit comprising a host device, an interface for interfacing the host unit with the DDS system, a controller for encoding and decoding data to and from the magnetic tape, an automatic track follower for performing automatic track following on the magnetic tape, a driver for driving the magnetic tape, a read/write channel for channeling data thereto and therefrom, a read/write head drum for transferring data to and from the magnetic tape, the controller, the automatic track follower, the driver, the read/write channel, and the read/write head drum all being under software programmable control.
    Type: Grant
    Filed: August 6, 1991
    Date of Patent: February 15, 1994
    Assignee: R-Byte, Inc.
    Inventors: Ross W. Johnston, Theodore D. Rees, Edward J. Rhodes
  • Patent number: 4686597
    Abstract: A tape recording/retrieving system includes a tape helically-wrapped about a cylindrical headwheel. When the headwheel rotates, the tape is hydrodynamically lifted above the rotating surface of the headwheel. A plurality of tape edge guides, illustratively three, disposed about the circumference of the headwheel, provide support surfaces for the tape. The edge guides include surfaces adjacent the cylindrical headwheel surface which are also subject to hydrodynamic forces when the headwheel rotates, causing the edge guides to "fly" away from the rotating surface, thus reducing wear problems on the headwheel and the guides. Using a knowledge of the system parameters, the edge guides are fabricated with a prestress so that they fly at a particular distance above the rotating surface which provides a supporting surface for the flying tape.
    Type: Grant
    Filed: September 27, 1985
    Date of Patent: August 11, 1987
    Assignee: RCA Corporation
    Inventor: Ross W. Johnston
  • Patent number: 4301687
    Abstract: A tension sensor is placed within a fluid bearing supporting a flexible tape at least partially wrapped around the periphery thereof. The bearing includes a source of pressurized fluid, such as air, and a plurality of metered orifii for admitting fluid into the region of the periphery to support the tape on a fluid bearing. The sensor includes a chamber and at least two metered orifice means, one in communication with the region of pressurized fluid supporting the tape and the other in communication with the source of pressurized fluid. A pressure sensor senses the pressure within the chamber, the pressure being directly proportional to the tension in the tape.
    Type: Grant
    Filed: May 19, 1980
    Date of Patent: November 24, 1981
    Assignee: Computer Peripherals, Inc.
    Inventors: James W. Jewitt, Ross W. Johnston, Sanford Platter
  • Patent number: 4075943
    Abstract: A high-speed fast acting actuator for an impact printing mechanism. The actuator has an improved high-strength low-mass actuating arm made of magnetic material. The actuating arm comprises a uniform thickness center lever and plates of magnetic material attached at the moment arm.
    Type: Grant
    Filed: October 21, 1975
    Date of Patent: February 28, 1978
    Assignee: Sperry Rand Corporation
    Inventor: Ross W. Johnston
  • Patent number: 3983803
    Abstract: A mechanism is disclosed for automatically positioning the print mechanism with respect to the forms and ribbon in a printer assembly. The automatic adjustment takes place for varying thicknesses of the forms, which is a function of the number of copies being printed and the type of form, as well as the variations in the thickness of the ribbon. The above-mentioned adjustment takes place after there has been a simulation of the print hammer striking the paper which may be a single-part or multi-part form.
    Type: Grant
    Filed: September 16, 1974
    Date of Patent: October 5, 1976
    Assignee: Sperry Rand Corporation
    Inventors: Roy D. Thomas, Ross W. Johnston
  • Patent number: 3981236
    Abstract: A printhead assembly, having an individual print hammer and actuator assembly for every other column of line print, includes a low mass hammer and a hairpin spring coupled to the hammer rear portion, and an actuator assembly with side arms meeting at the arm tip for rapidly impacting characters on a type band. A plural flexure spring assembly provides uniform stress during actuator assembly movement and enables hammer and actuator positional adjustment to be made by frontal access, and a slotted bearing assembly inclines each print hammer at a slight angle off the perpendicular to the print line and the plane of the record medium.
    Type: Grant
    Filed: November 3, 1975
    Date of Patent: September 21, 1976
    Assignee: Sperry Rand Corporation
    Inventors: Ross W. Johnston, Barrie W. Witty
  • Patent number: 3981235
    Abstract: The mechanism herein relates to the automatic positioning of the print mechanism with respect to the forms and ribbon in a printer assembly. The automatic adjustment takes place for varying thicknesses of the forms, which is a function of the number of copies being printed and the type of form, as well as the variations in the thickness of the ribbon. The abovementioned adjustment takes place after there has been a simulation of the print hammer striking the paper which may be a single-part or multi-part form. Simulation is obtained by extending a probe to deform the forms in the same manner as a print hammer deforms the forms in the actual printing operation.
    Type: Grant
    Filed: June 21, 1974
    Date of Patent: September 21, 1976
    Assignee: Sperry Rand Corporation
    Inventors: Roy D. Thomas, Ross W. Johnston
  • Patent number: 3964384
    Abstract: A plurality of small pin-shaped low-mass print hammers are slideably mounted in a row opposite moving type. The low-mass print hammers are individually moved a short distance from a ready position to impact the moving type by individual highspeed actuators when a selected character is juxtaposed each of the hammers. The print hammers and actuators are returned to the ready position by spring means cooperating with damper means.
    Type: Grant
    Filed: March 11, 1974
    Date of Patent: June 22, 1976
    Assignee: Sperry Rand Corporation
    Inventor: Ross W. Johnston