Patents by Inventor John C. Greenwood

John C. Greenwood 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: 4942766
    Abstract: In a transducer, e.g. a pressure transducer, the sensing element comprises a torsional oscillator provided with magnetic means for feedback of signals to maintain oscillation. Typically the sensing element is formed by selective etching from a body of single crystal silicon.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: July 24, 1990
    Assignee: STC PLC
    Inventors: John C. Greenwood, James M. Naden
  • Patent number: 4884450
    Abstract: A pressure sensor includes a resonator element (14) mounted on an optical fibre ferrule (11) whereby light signals for maintaining the resonator in a state of oscillation and for returning a modulated signal to a remote station are coupled to the resonator. The resonator is located in an evacuated cavity and is mounted on a flexible diaphragm whereby pressure changes may be detected as changes in the resonant frequency.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: December 5, 1989
    Assignee: STC PLC
    Inventors: John C. Greenwood, Peter W. Graves, Rosamund C. Neat
  • Patent number: 4813271
    Abstract: A strain or pressure responsive transducer comprises a pair of elongate beam resonators arranged end to end and provided with a flexible coupling therebetween. The arrangement oscillates e.g. in a double see-saw or butterfly mode. The transducer is disposed on a diaphragm whereby strain may be transmitted to the oscillatory system. The frequency of oscillation is a function of this strain.
    Type: Grant
    Filed: April 3, 1987
    Date of Patent: March 21, 1989
    Assignee: STC PLC
    Inventor: John C. Greenwood
  • Patent number: 4691117
    Abstract: A contactless electrical switch includes a switch element comprising a piezo-resistive transducer (25). Coded toothed cams (16) operated via a shaft (14) deflect the transducer (25) causing corresponding changes in stress and hence resistance. The output of the transducer is amplified and fed to logic circuitry which determines a corresponding current path.
    Type: Grant
    Filed: March 3, 1986
    Date of Patent: September 1, 1987
    Assignee: International Standard Electric Company
    Inventors: John C. Greenwood, Robert J. Hodges, Robert Sheppard
  • Patent number: 4660418
    Abstract: A flexible hinge device comprises a laminar silicon body having a groove portion etched away to define a thin flexible strip joining two rigid end portions. The silicon forming the hinge is usually of a single crystal structure. Break-off supports may be provided to support the structure prior to use.
    Type: Grant
    Filed: September 17, 1984
    Date of Patent: April 28, 1987
    Assignee: International Standard Electric Corporation
    Inventors: John C. Greenwood, David Wilson
  • Patent number: 4655091
    Abstract: A transducer responsive to rotational movement comprises a support member on which a shaft is rotatably mounted. Relative movement between the member and the shaft is sensed by flexure of a strip of a piezo-resistive mateial. Typically, the strip is facribed from signle crystal silicon.
    Type: Grant
    Filed: March 28, 1984
    Date of Patent: April 7, 1987
    Assignee: International Standard Electric Corporation
    Inventor: John C. Greenwood
  • Patent number: 4636829
    Abstract: An integrated circuit incorporates a PIN diode connected to the gate of an FET. The semiconductor layers used to construct the diode are also the layers used to construct the FET, and provide a relatively low capacitance per unit area for the diode compared with that of the gate of the FET.
    Type: Grant
    Filed: August 16, 1984
    Date of Patent: January 13, 1987
    Assignee: ITT Industries, Inc.
    Inventors: John C. Greenwood, George H. B. Thompson
  • Patent number: 4567451
    Abstract: A resonator device comprises an elastic beam driven electrostatically at its natural frequency, or an harmonic thereof, by voltage pulses applied to an integral paddle member. The voltage pulses are derived from optical pulses fed via an optical fibre and reflected from the paddle member to a photodiode array. There is thus minimal coupling between the beam and the drive system. A positive feedback loop is provided in which light retroreflected from the paddle member is recaptured by the optical fibre and electronically detected, amplified and fed back in phase with the beam oscillations by modulating the optical pulses.
    Type: Grant
    Filed: June 1, 1983
    Date of Patent: January 28, 1986
    Assignee: International Standard Electric Corporation
    Inventor: John C. Greenwood
  • Patent number: 4503715
    Abstract: An electro-mechanical load sensor is in the form of a mechanical resonant system with electrostatically coupled electrodes. The mechanical system is formed from a silicon wafer by a selective etching process and comprises a filament of between two terminations 12 and 13 carrying transverse plates M.sub.1 and M.sub.2. Electrostatic (capacitive) coupling to plate electrodes E.sub.1, E.sub.2, E.sub.3 in a self-exciting circuit drives the system. The resonant frequency for angular S vibrations with plates M.sub.1 and M.sub.2 in anti-phase varies with applied load L and is thus a measure of this load.
    Type: Grant
    Filed: February 8, 1983
    Date of Patent: March 12, 1985
    Assignee: International Telephone and Telegraph Corporation
    Inventor: John C. Greenwood
  • Patent number: 4480162
    Abstract: An electrical contact element includes a support component of an effectively electrically insulating material, especially silicon, the support component including a supporting body and an armature integral with and hingedly connected to the supporting body, the armature carrying at least one electrical contact. The electrical contact element is accommodated in a housing which is hermetically sealed and either filled with an inert gas or evacuated. The housing includes at least one fixed contact, and the supporting body is shaped as a frame which has a recess in which the armature is received when electrical contact is established between the electrical contact carried by the armature and the fixed electrical contacts carried by the housing. The electrical contact element is made by material-removing techniques from a single substantially plate-shaped member and then the electrical contact is vapor-deposited thereon.
    Type: Grant
    Filed: February 26, 1982
    Date of Patent: October 30, 1984
    Assignee: International Standard Electric Corporation
    Inventor: John C. Greenwood
  • Patent number: 4305298
    Abstract: Semiconductor transducer devices are provided, some being formed from a single crystal and having a flexible portion which is vibratable. Also a multi-element is disclosed which is a body including mechanical semiconductor resonator. The body has a transverse valley across its width. A comb-like array of flexible silicon cantilevers extend from one end of the body. Each cantilever is adapted to respond to a periodic force such that each has a different vibrational frequency. An alternative embodiment includes an accelerometer having a block with a three cantilever array with a semiconductor filament fixed in tension between each adjacent pair. The middle cantilever is longer than the other two. A further alternative employs elements to support a crystal at two nodal points of vibration.
    Type: Grant
    Filed: June 8, 1979
    Date of Patent: December 15, 1981
    Assignee: ITT Industries, Inc.
    Inventor: John C. Greenwood
  • Patent number: 4293373
    Abstract: A silicon transducer including a silicon frame with one or more lands extending from a diaphragm or the like. The lands are interconnected by two thin strips formed integrally with the lands. The strips are essentially the transducer. The transducer is constructed by etching a boron doped wafer with a mixture of catechol, ethylene diamine and water.
    Type: Grant
    Filed: February 26, 1980
    Date of Patent: October 6, 1981
    Assignee: International Standard Electric Corporation
    Inventor: John C. Greenwood
  • Patent number: 4244225
    Abstract: An acceleration sensor including a block having comb-like projections forming three cantilever beams. A semiconductor filament is then fixed in tension between each adjacent pair of the beams. The beam on one extreme side has a length equal to that of the beam on the other, whereas the center beam is longer than the other two.
    Type: Grant
    Filed: June 8, 1979
    Date of Patent: January 13, 1981
    Assignee: ITT Industries, Inc.
    Inventor: John C. Greenwood
  • Patent number: 4229979
    Abstract: A silicon transducer including a silicon frame with one or more lands extending from a diaphragm or the like. The lands are interconnected by two thin strips formed integrally with the lands. The strips are essentially the transducer. The transducer is constructed by etching a boron doped wafer with a mixture of catechol, ethylene diamine and water.
    Type: Grant
    Filed: May 29, 1979
    Date of Patent: October 28, 1980
    Assignee: International Standard Electric Corporation
    Inventor: John C. Greenwood
  • Patent number: 4182937
    Abstract: A piezo-electric transducer element is disclosed which is formed by selected etchings from boron doped silicon. The transducer includes a diaphragm and a spring lever adapted to bias the transducer element into a state of strain so that a vibration of the diaphragm is transmitted to the transducer element. The transducer element is particularly suitable for use in a telephone microphone.
    Type: Grant
    Filed: September 21, 1978
    Date of Patent: January 8, 1980
    Assignee: International Standard Electric Corp.
    Inventor: John C. Greenwood
  • Patent number: 4131985
    Abstract: This relates to a semiconductor device and method for making same. At least one semiconductor device is formed in a polished silicon slice, and the device is framed by a deep diffusion of boron. The surface of the slice is then coated with a layer of silicon nitride, and a glass ceramic body is bonded to the silicon nitride layer. The device is next isolated by isotropic etching, and the silicon from beneath the device is removed with a selective etch so that metal interconnections can be made to the underside of the device.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: January 2, 1979
    Assignee: ITT Industries, Inc.
    Inventors: John C. Greenwood, John M. Young
  • Patent number: 4116531
    Abstract: A fiber optic switch utilizes an unclad light guide arranged adjacent to a diaphragm of absorbing material. Operation of a push-button presses the diaphragm into contact with the light guide for attenuating the light. Several light guides may be employed to provide an n-of-m code switch matrix.
    Type: Grant
    Filed: April 1, 1977
    Date of Patent: September 26, 1978
    Assignee: International Standard Electric Corporation
    Inventor: John C. Greenwood