Patents Represented by Attorney David A. Boone
  • Patent number: 4273039
    Abstract: An electromagnet and a permanent magnet are arranged in parallel between first and second pole pieces having a metallic spring tine coupled to the first pole piece and disposed to be attracted to the second pole piece by the magnetic field of the permanent magnet. A sensing coil is positioned to sense magnetic flux changes resulting from changes in position of the metallic spring tine. In operation the spring tine is displaced to the second pole piece and captured at a home position by field energy from the permanent magnet. When there is a demand for printing, the electromagnet is energized in a first polarity such that its reluctance to the field of the permanent magnet is minimized and the flux from the permanent magnet is attracted to pass through the core of the electromagnet thereby nullifying the traction between the spring tine and the second pole piece and the spring tine is released.
    Type: Grant
    Filed: August 3, 1979
    Date of Patent: June 16, 1981
    Assignee: Hewlett Packard Company
    Inventors: Zong S. Luo, Todd M. Woodcock
  • Patent number: 4264958
    Abstract: An input signal is mixed with sampling signals from oscillators which vary the frequency of the sampling signal from a first frequency to a second frequency. The resulting Intermediate Frequency (IF) signal is processed and digital values are stored in a memory in response thereto. Waveforms are then displayed which correspond to these frequency and amplitude values. Various input and display circuits facilitate the display and interpretation of these waveforms.
    Type: Grant
    Filed: August 10, 1978
    Date of Patent: April 28, 1981
    Assignee: Hewlett-Packard Company
    Inventors: Joseph Rowell, Jr., Michael S. Marzalek, Michael J. Neering
  • Patent number: 4260286
    Abstract: A system for use at dams, diversion canals, and the like includes a fish ladder for enabling fish to travel both upstream and downstream without injury past man-made obstacles such as dams. The fish ladder comprises a series of dish-like compartments to which water is made to flow from top to bottom. Auxiliary water input to each dish in the series is maintained to create the desired turbulence and flush debris from the ladder. Also included is a power predator seine chamber at the bottom of the fish ladder for chumming predator fish from the waters at the bottom of the fish ladder. The predator fish can be sorted out when the seine is raised. Repetitive traveling screens move through the water and allow the removal of water from a body of water without removing or damaging fish therein. The screen's rotation, size of the screen material, and the angle of the screen to primary water flow allow the migrating fish to keep moving in the desired direction while large volumes of water are diverted.
    Type: Grant
    Filed: April 19, 1979
    Date of Patent: April 7, 1981
    Inventor: Robert R. Buchanan
  • Patent number: 4257104
    Abstract: An input signal is mixed with sampling signals from oscillators which vary the frequency of the sampling signal from a first frequency to a second frequency. The resulting Intermediate Frequency (IF) signal is processed and digital values are stored in a memory in response thereto. Waveforms are then displayed which correspond to these frequency and amplitude values. Various input and display circuits facilitate the display and interpretation of these waveforms.
    Type: Grant
    Filed: August 10, 1978
    Date of Patent: March 17, 1981
    Assignee: Hewlett-Packard Company
    Inventors: Larry R. Martin, Michael S. Marzalek
  • Patent number: 4253152
    Abstract: An input signal is mixed with sampling signals from oscillators which vary the frequency of the sampling signal from a first frequency to a second frequency. The resulting Intermediate Frequency (IF) signal is processed and digital values are stored in a memory in response thereto. Waveforms are then displayed which correspond to these frequency and amplitude values. Various input and display circuits facilitate the display and interpretation of these waveforms.
    Type: Grant
    Filed: August 10, 1978
    Date of Patent: February 24, 1981
    Assignee: Hewlett-Packard Company
    Inventor: Steven N. Holdaway
  • Patent number: 4244024
    Abstract: An input signal is mixed with sampling signals from oscillators which vary the frequency of the sampling signal from a first frequency to a second frequency. The resulting Intermediate Frequency (IF) signal is processed and digital values are stored in a memory in response thereto. Waveforms are then displayed which correspond to these frequency and amplitude values. Various input and display circuits facilitate the display and interpretation of these waveforms.
    Type: Grant
    Filed: August 10, 1978
    Date of Patent: January 6, 1981
    Assignee: Hewlett-Packard Company
    Inventors: Michael S. Marzalek, Lynn M. Wheelwright
  • Patent number: 4242637
    Abstract: The relative occurrence of first and second input signals is determined by sampling the output signal of a comparator which compares a predetermined voltage source output signal with the output signal from a ramp generator which is triggered by the first input signal. The sampling signal is provided in response to the second input signal after a preselected time delay. A balancing calibration is used to insure that if the signals are coincident, the ramp generator signal is equal to the voltage reference signal at the moment of sampling. Therefore, the precedence of the first and second input signals is determined by sampling the comparator output signal in response to the sampling signal and determining the relative values of the ramp voltage signal and the voltage reference signal at the time of sampling.
    Type: Grant
    Filed: November 3, 1978
    Date of Patent: December 30, 1980
    Assignee: Hewlett-Packard Company
    Inventor: Keith M. Ferguson
  • Patent number: 4234845
    Abstract: Both positive and negative time interval measurements between start and stop channel signals are made without ambiguity during repetitive measurements. Circuitry monitors the start and stop channel signals and automatically changes the arming of the measurement circuitry whenever drifting of the signals requires a change in arming. Once the start or stop channel event is chosen as the initial source of the arming signal, subsequent arming signal selections are accomplished automatically.
    Type: Grant
    Filed: November 13, 1978
    Date of Patent: November 18, 1980
    Assignee: Hewlett-Packard Company
    Inventor: Mark S. Allen
  • Patent number: 4219053
    Abstract: Two movable members are selectable positioned to form a passageway for handling dual in-line packages. A wheel, comprising resilient material, and a spreader member are selectable positioned in correspondence with the movable members to engage the leads on either side of the package and vertically straighten them. Lateral straightness of the leads, as well as various other package anomalies, are detected by optical scanning.
    Type: Grant
    Filed: October 30, 1978
    Date of Patent: August 26, 1980
    Inventors: Clifford A. Tyner, Dean L. Westbrook
  • Patent number: 4219744
    Abstract: A compact, DC-coupled Schmitt trigger circuit is disclosed for providing fast switching in response to differential current signals from an input source such as an amplifier. The circuit includes first and second matched pairs of transistors disposed for performing switching and feedback functions, respectively, and for producing a voltage at an input or base of the first pair equal to the sum (AND function) of the source voltage and the voltage at an emitter of the feedback pair. In response to the applied current signals, the transistors of the second matched pair are always in a conducting state (and requires no extra time to turn on) regardless of the conducting state of either of the transistors of the first matched pair.
    Type: Grant
    Filed: February 3, 1978
    Date of Patent: August 26, 1980
    Assignee: Hewlett-Packard Company
    Inventor: Charles E. Shinn, II
  • Patent number: 4214266
    Abstract: A visual aid system for assisting an operator while he maneuvers a vehicle comprises a closed circuit video system having distance measuring apparatus. The system enables the operator to see behind the vehicle and, through the use of the distance indicating apparatus, the operator can tell how far the rear of the vehicle is from objects seen via the video system.
    Type: Grant
    Filed: June 19, 1978
    Date of Patent: July 22, 1980
    Inventor: Charles H. Myers
  • Patent number: 4205627
    Abstract: Transparent panels form a plurality of enclosures which have inlet and exhaust ventilation openings. The input ventilation openings are coupled to a plenum chamber and the exhaust ventilation openings are coupled to an exhaust chamber. Air flow is maintained from the plenum chamber through the enclosures and out the exhaust chamber by a pressure differential between the plenum chamber and the exhaust chamber. This is accomplished by maintaining the plenum chamber at a positive pressure with respect to the enclosures and maintaining the exhaust chamber at a negative pressure with respect to the enclosures. Air is not recirculated through the cages, and both the input and the exhaust air is sterilized by various devices in the path of the ventilation stream. Cleaning of the enclosures is accomplished by flushing any waste material into the pathway coupling the enclosures with the exhaust chamber.
    Type: Grant
    Filed: January 10, 1978
    Date of Patent: June 3, 1980
    Inventor: Robert R. Buchanan
  • Patent number: 4196694
    Abstract: A method of construction of an artificial reef with individual reef elements manufactured from recycled or new materials. Each reef element is constructed, for example, from used tire casings which are cut in one of several different ways. One type of reef element is constructed by cutting a tire casing longitudinally along its tread area leaving a single small web area at one side short of the tire being completely severed into individual loop segments, or a pair of webs on opposite sides of the tread. Tire casings cut in this way are then fanned open and attached to one of two types of bases. The second and third types of reef elements are constructed from several side walls or half tires, also mounted on one of the two types of bases. Enumerable other reef element configurations are possible by cutting the tire casings in other ways.
    Type: Grant
    Filed: February 9, 1978
    Date of Patent: April 8, 1980
    Inventor: Robert R. Buchanan
  • Patent number: 4189621
    Abstract: An encoding circuit provides an improved interface code of the CMI (Code Mark Inversion) type for transferring binary information between different points within terminal stations for digital communication, such as telephone exchange stations. Encoded output signals, in the CMI format or code, are produced with respect to a clock related signal in a manner such that each positive or negative transition of the encoded output signals occur at the end or at the beginning of a data bit period of the output signals, irrespective of whether the binary value of the input signals to be encoded is 0 or 1. Signal trailing edges, which are to be used for clock recovery by a subsequent decoder, are triggered by clock pulses, and are not derived from different signal channels of the encoding circuitry which, typically, would have made the relative phasing of the signals in the channels critical.
    Type: Grant
    Filed: February 3, 1978
    Date of Patent: February 19, 1980
    Assignee: Hewlett-Packard Company
    Inventor: Peter M. Scott
  • Patent number: 4182786
    Abstract: Apparatus for the controlled hot waxing of skis is disclosed. The apparatus includes an upwardly opening semi-cylindrical tub with closed ends. The tub is constructed of heat conductive material, and a heater is mounted on the exterior radial surface of the tub so that wax placed therein will be caused to melt at the appropriate temperature. A solid aluminum roller having axial struts projecting from the opposite ends thereof is rotatably mounted on the closed ends of the cylinder so that the lower portion of the roller will project into the melted wax and the upper portion of the roller will provide an exposed surface for contact with a ski. The roller and struts are of heat conductive material so that heat from the end walls of the tub is conducted through the struts to the roller. A covering is applied to the radial surface of the roller and has a preselected softness so that a ski passing over the covering will remain in full contact with the covering over the entire width of the ski.
    Type: Grant
    Filed: August 4, 1978
    Date of Patent: January 8, 1980
    Inventor: Terry J. Hertel
  • Patent number: 4172281
    Abstract: A minicomputer comprises a microprogrammable central processing unit wherein micro-instruction execution speed is optimized through the use of variable micro-instruction timing logic and by grouping micro-instruction according to execution time. Furthermore, data paths are arranged so that micro-routines that implement more complex operations, i.e., memory reference instructions, follow the fastest route possible. When micro-instructions requiring longer data paths are programmed, the computer dynamically varies the length of the microcycle to be a function of both the type of micro-instruction to be executed and the state of the minicomputer when the micro-instruction is to be executed. A microprogrammable processor port is provided to allow coupling of external hardware, e.g., I/O devices, other processors, etc., directly to the microprogrammed control processor.
    Type: Grant
    Filed: August 30, 1977
    Date of Patent: October 23, 1979
    Assignee: Hewlett-Packard Company
    Inventor: Philip Gordon
  • Patent number: 4164648
    Abstract: Measurement of a time interval between a start and a stop event is made by activating a start oscillator in response to the start event and activating a stop oscillator in response to the stop event. The number of cycles of each respective oscillator signal which occur between the activation of each oscillator and the coincidence of the respective oscillator signal with that of an independent time base is determined. The number of cycles of the time base signal between the coincident points of it and the start and stop oscillator signal is also determined. These numbers, which are always integers, are used along with the values for the time base period and the difference in frequency between the time base oscillator and the start and stop oscillators to calculate the time interval. Resolution of the measurement is dependent on the frequency difference between the time base signal and the start and stop oscillator signals.
    Type: Grant
    Filed: June 23, 1978
    Date of Patent: August 14, 1979
    Assignee: Hewlett-Packard Company
    Inventor: David C. Chu
  • Patent number: 4161017
    Abstract: Interlocking hinges are attached to printed circuit boards and coupled together to form a stack of printed circuit boards. Access to each board is possible by rotating the stack at a selected hinge to expose a selected board. A projection and an opening on each hinge mate with openings and projections on other hinges to allow easy removal or addition of a board from the stack when the hinges are in one relative position, but to create an interference fit in a second relative position, thereby causing the hinges to lock together and form a rigid structure.
    Type: Grant
    Filed: August 8, 1977
    Date of Patent: July 10, 1979
    Assignee: Hewlett-Packard Company
    Inventors: Perry H. Pierce, Dan L. Prendergast
  • Patent number: 4139903
    Abstract: Clock signals, data words and qualifier signals are received via monitor probes during a data acquisition mode, selected data words being stored in a memory in response to the clock and qualifier signals. The stored data words may then be displayed in a tabular or a map format on a cathode ray tube screen. Data words may be acquired randomly, i.e., in a free-running sampling mode, or acquired selectively by using pattern recognition and delay trigger circuits. Using the tabular display format, data words are displayed as ones and zeroes. Using the map display format, each data word thus acquired is displayed on the CRT screen as a dot during a subsequent display mode. The position of each dot on the CRT screen uniquely identifies its address or state value. The most significant bits determine the vertical position on the CRT screen and the least significant bits determine the horizontal position of the dot. The intensity of the dot indicates the relative frequency of occurrence of that logic state.
    Type: Grant
    Filed: May 31, 1977
    Date of Patent: February 13, 1979
    Assignee: Hewlett-Packard Company
    Inventors: Justin S. Morrill, Jr., William A. Farnbach, Charles T. Small
  • Patent number: D259324
    Type: Grant
    Filed: September 1, 1978
    Date of Patent: May 26, 1981
    Inventor: Terry J. Hertel