Patents Represented by Attorney A. F. Duke
  • Patent number: 4137985
    Abstract: A vehicle security system includes a door locking mechanism and control circuitry which prevents access to the vehicle interior unless a door lock key is used thus making it unnecessary to specifically lock the doors upon exiting the vehicle. Steering shaft lock means are also energizable by operation of the door lock key permitting elimination of the ignition key and lock cylinder.
    Type: Grant
    Filed: November 25, 1977
    Date of Patent: February 6, 1979
    Assignee: General Motors Corporation
    Inventor: Frank J. Winchell
  • Patent number: 4138723
    Abstract: A digital speed control system including a processor performing arithmetical and logic operations in response to command inputs from the operator to maintain the present vehicle speed, to accelerate at a substantially constant rate to a new cruising speed or to a previously established cruising speed is disclosed. Certain processor operations are phased to speed sensor pulses to permit rate of change of speed computations to be performed with minimum hardware.
    Type: Grant
    Filed: August 12, 1977
    Date of Patent: February 6, 1979
    Assignee: General Motors Corporation
    Inventors: Carl A. Nehmer, Douglas W. Sweet
  • Patent number: 4113984
    Abstract: Audio control circuitry for a four-channel system is disclosed which permits volume adjustment from a single master volume control potentiometer and balance adjustment from a single left-right balance potentiometer and a single front-rear balance control potentiometer.
    Type: Grant
    Filed: November 15, 1976
    Date of Patent: September 12, 1978
    Assignee: General Motors Corporation
    Inventors: William F. Gilbert, Larry D. Lucas
  • Patent number: 4090198
    Abstract: 1. A reflectance modulator exhibiting an omni-azimuttal reflectance pattern comprising a microwave lens for focusing electromagnetic energy, a plurality of reflector means positioned on a focal surface of said lens and including a gaseous plasma, means for sequentially controlling the ionization level of said plasma to modulate the reflectance of said energy.
    Type: Grant
    Filed: August 31, 1964
    Date of Patent: May 16, 1978
    Assignee: General Motors Corporation
    Inventors: Eugene T. Canty, Russell P. Tow, Frank J. Spayth, Richard A. Morrow, Charlie B. Smith
  • Patent number: 4076959
    Abstract: Control circuitry for a multi-channel audio system is disclosed which includes left and right signal processing channels and a DC control section. Each processing channel includes balance and volume sections which are connected with the DC control circuitry and controlled from respective balance and volume potentiometers connected with the DC control section. Each channel further includes a tone control section and more specifically treble and bass sections connected with the DC control circuitry and controlled from a tone potentiometer. The response of the bass section is also controlled as a function of the setting of the volume potentiometer to achieve a loudness function. The volume control circuitry is designed to produce a linear relationship between the DC control voltage and signal attenuation as measured in decibels. Current steering circuitry is employed in both amplitude and tone control.
    Type: Grant
    Filed: October 8, 1976
    Date of Patent: February 28, 1978
    Assignee: General Motors Corporation
    Inventors: William F. Gilbert, Burtron D. Schertz, Lester Wilkinson
  • Patent number: 4051434
    Abstract: Circuitry for developing a binary number proportional to the frequency of an input signal includes a first and second shift register and an adder. Timing control circuitry establishes a 16 bit computation period and also develops a fixed binary number. Circuit means are provided for interconnecting the adder and the firsrt register for increasing the content of the register by the fixed binary number once each cycle of the input signal and for reducing the content of the register by a fixed proportion each of the computation periods occurring during each cycle of the input signal. The content of the first register is transferred to the second or buffer register each cycle of the input signal and display means are provided for displaying the input frequency of a function as the binary number contained in the second register.
    Type: Grant
    Filed: May 28, 1976
    Date of Patent: September 27, 1977
    Assignee: General Motors Corporation
    Inventor: Douglas W. Sweet
  • Patent number: 4047111
    Abstract: An integrated circuit responsive to the output of an AM local oscillator and an AFC signal for developing a DC signal for applying a tuning voltage to the front end of a FM receiver which is a function of the local oscillator frequency and the drift of the FM front end.
    Type: Grant
    Filed: July 19, 1976
    Date of Patent: September 6, 1977
    Assignee: General Motors Corporation
    Inventor: Paul N. Barr
  • Patent number: 4039956
    Abstract: An electronic frequency indicator for an AM/FM receiver utilizing a plurality of light-emitting diodes. The intensity of the diodes is varied to achieve greater resolution for the number of diodes in the indicator.
    Type: Grant
    Filed: September 5, 1975
    Date of Patent: August 2, 1977
    Assignee: General Motors Corporation
    Inventors: Ronald W. Shimanek, Mark A. Franklin
  • Patent number: 4015254
    Abstract: Various switches of a keyboard are connected with a voltage divider network to establish an analog voltage for respective switch closures. The analog voltage is stored on a capacitor and converted by an analog-to-digital converter for input to a computer.
    Type: Grant
    Filed: December 4, 1975
    Date of Patent: March 29, 1977
    Assignee: General Motors Corporation
    Inventor: Earl R. Strandt
  • Patent number: 4001811
    Abstract: An NRZL bit stream is encoded by shifting the bit stream through a 9 bit storage register while logic gates detect and compare the level of adjacent bits stored in the register. The state of an output bit stream is changed if the bits stored in positions 8 and 9 of the register are alike and the change occurs at one or the other of two different times during bit time depending upon whether the pair of like bits are "1's" or "0's". If in addition to the detection of a pair of like bits in positions 8 and 9, an alternate bit pattern is detected in positions 1 through 7 of the register, changes in the output bit stream are forced at a rate of 11/2 bit time intervals until a pair of like bits are detected in positions 5 and 6 of the register. The first of the 11/2 bit time interval state changes occurs at 2 or 21/2 bit times after the state change resulting from detection of a pair of like bits depending upon the level of the bits stored in position 7 of the register.
    Type: Grant
    Filed: January 28, 1972
    Date of Patent: January 4, 1977
    Assignee: General Motors Corporation
    Inventor: Duane E. McIntosh
  • Patent number: 3983354
    Abstract: A rotary switch comprising a housing, a cover, three stationary contacts, a rotor, an O-ring seal, and a combination sealing and driving member. The switch is mounted on the end of a door lock cylinder assembly of a vehicle and is connected with the vehicle anti-theft system so that insertion of a key into the lock cylinder and rotation of the key in one direction arms the alarm system through the switch while rotation in the opposite direction disarms the system. The switch is entirely self-contained and weatherproof.
    Type: Grant
    Filed: June 30, 1975
    Date of Patent: September 28, 1976
    Assignee: General Motors Corporation
    Inventors: Joseph E. Gammie, Bert R. Wanlass
  • Patent number: 3974472
    Abstract: A domestic range including a touch control and display panel and digital control logic for energizing power circuits controlling the various range heater elements in response to a program entered by the user by touching certain areas of the panel. The control logic also controls the displays located behind the panel to provide feedback to the user of the program selected.
    Type: Grant
    Filed: May 5, 1975
    Date of Patent: August 10, 1976
    Assignee: General Motors Corporation
    Inventor: Robert R. Gould, Jr.
  • Patent number: 3967239
    Abstract: An anti-theft system for a motor vehicle which includes an ARM ENABLE latch and an ARM latch which establish a circuit arming condition in response to movement of a key operated switch from a neutral to an arming position. An ALARM latch is responsive to a plurality of sensor switches which in turn are responsive to whether a compartment of the vehicle is open or closed. If a compartment is opened after the arming condition has been established the ALARM latch causes the vehicle horn to be periodically energized for a predetermined interval of time. Delay means are provided for preventing a change of state of the various latches for a predetermined interval of time after actuation of the switch controlled input to the latch so as to prevent inadvertent triggering of the latch circuit. Indicator means are provided for detecting a malfunction in the system which would prevent the circuit arming condition from being established.
    Type: Grant
    Filed: November 15, 1974
    Date of Patent: June 29, 1976
    Assignee: General Motors Corporation
    Inventor: Robert E. Steele
  • Patent number: 3967203
    Abstract: A circuit for generating a center tuned pulse for stopping the operation of a signal seeking FM receiver includes means for developing a bias current which is added to the output currents of the quadrature detector of the receiver. A stopping pulse is generated whenever the difference between the output currents is less than the bias current and a 10.7 mHz. signal is present in the IF amplifier.
    Type: Grant
    Filed: March 3, 1975
    Date of Patent: June 29, 1976
    Assignee: General Motors Corporation
    Inventors: Larry D. Lucas, Burtron D. Schertz, Lester Wilkinson
  • Patent number: 3952161
    Abstract: An audio processor is disclosed which includes circuitry for modifying pure left and right audio signals by blending the left audio signal with the right audio signal as a function of frequency and for rolling off the higher frequencies of the blended signal. The processor further includes circuitry for selecting complementary portions of a blended, rolled-off audio signal and a pure audio signal as a function of the RF carrier strength to improve the overall listenability of the audio.
    Type: Grant
    Filed: October 21, 1974
    Date of Patent: April 20, 1976
    Assignee: General Motors Corporation
    Inventors: William F. Gilbert, Burtron D. Schertz, Wayne A. Smith, Lester Wilkinson
  • Patent number: 3950741
    Abstract: The load monitoring circuit includes a solid state current sensor including a positive temperature coefficient (PTC) resistor and a heater resistor. The heater resistor is connected in series with the load and in parallel with the PTC resistor. A third resistor is connected in series with the PTC to form a voltage divider. Current drawn by the load through the heater resistor raises the temperature of the PTC resistor above its anomaly temperature causing the voltage at the divider junction to abruptly switch from a high to a low state to indicate the status of the load.
    Type: Grant
    Filed: October 29, 1974
    Date of Patent: April 13, 1976
    Assignee: General Motors Corporation
    Inventor: Thaddeus Schroeder
  • Patent number: 3947774
    Abstract: A circuit for terminating the scanning operation of a signal seeking receiver includes a double-ended limit detector which responds to the AFC voltage developed in the receiver to produce a stop signal when the frequency deviations of the IF signal are within a narrow band centered about 10.7 Mhz.
    Type: Grant
    Filed: November 25, 1974
    Date of Patent: March 30, 1976
    Assignee: General Motors Corporation
    Inventors: Timothy P. Glennon, Douglas E. Martin
  • Patent number: 3947771
    Abstract: An automatic gain control system in which a DC voltage proportional to an on-channel signal is used to control the gain of the RF stage but is keyed from the wide band output of the mixer stage to reduce the possibility of mixer overload.
    Type: Grant
    Filed: February 21, 1975
    Date of Patent: March 30, 1976
    Assignee: General Motors Corporation
    Inventors: James E. Mathews, Wayne A. Smith, Lester Wilkinson