Patents by Inventor Stephen E. Clark

Stephen E. Clark 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: 6030480
    Abstract: A method and apparatus for manufacturing prestressed piezoelectric actuators which maximizes output, and increases the precision and efficiency with which the multi-layer actuators are made. Individual layers of the piezoelectric actuators are automatically stacked and registered with respect to each other within press members prior to bonding the layers to each other with a thermoplastic adhesive. Compressive force is applied while heat is conductively transferred from a heating element to the actuator in order to raise the temperature of each of the layers above the melting point of the thermoplastic. The temperature of the heating element is then decreased until the temperature of the actuator layers drops to below the melting point of the thermoplastic adhesive, thereby bonding the layers. Compressive force is then released, and the actuators are removed, further cooled and polarized.
    Type: Grant
    Filed: July 21, 1998
    Date of Patent: February 29, 2000
    Assignee: Face International Corp.
    Inventors: Samuel A. Face, Jr., Stephen E. Clark
  • Patent number: 5849125
    Abstract: A method for manufacturing pre-stressed piezoelectric actuators using a pre-curved piece of ceramic is provided. An adhesive, preferably a polyimide, is disposed between a metal pre-stress metal layer and a pre-curved PZT ceramic. The entire composite structure is heated to a temperature above the melting point of the adhesive material and then subsequently cooled to allow the adhesive layer to set. As a result of the difference in thermal contraction rates of the materials, the pre-curved PZT ceramic is compressively stressed. This pre-stressing provides a piezoelectric actuator which is durable, and produces a higher displacement than a conventional piezoelectric actuator.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: December 15, 1998
    Inventor: Stephen E. Clark
  • Patent number: 5816780
    Abstract: A piezoelectrically actuated fluid pump including a pump housing, a pump chamber, inlet and outlet ports for communicating the pump chamber with the exterior of the pump housing, valves for opening and closing the ports, two prestressed piezoelectric diaphragm members which are self-actuated, and a power source is provided. The diaphragm members include a prestressed piezoelectric element which is durable, inexpensive and lightweight as compared with prior diaphragm pumps of comparable discharge capacity, and is actuated via electrical signals from an outside power source. No exterior mechanical parts for driving the diaphragm members are necessary. A modification is disclosed in which a central computer independently controls the phase angle of oscillation of the two diaphragm members, providing precise flow rate control.
    Type: Grant
    Filed: April 15, 1997
    Date of Patent: October 6, 1998
    Assignee: Face International Corp.
    Inventors: Richard P. Bishop, Bradbury R. Face, Samuel A. Face, Stephen E. Clark, Norvell S. Rose
  • Patent number: 5348041
    Abstract: Automatically resetting mechanical valve is used to control unwanted discharge of liquids less dense than water, principally oil, which may be present in waste water flows. The valve is closed by the sinking of a primary flow which closes a primary orifice, and the floating of a secondary float which closes a smaller secondary orifice. The primary float is less dense than water but more dense than oil. The secondary float is less dense than both oil and water. When the primary float becomes sufficiently immersed in oil, the primary float sinks and effectively closes the primary orifice in an outlet conduit. In the event of evaporation or removal of liquid from the valve, the (smaller) secondary orifice automatically opens, thereby allowing hydrostatic pressure inside and outside of the outlet conduit to equalize. Upon reintroduction of water to the device, the primary float unseats and the valve automatically re-opens.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: September 20, 1994
    Inventor: Stephen E. Clark
  • Patent number: 5191068
    Abstract: A method of removing an antigenic substance from a fluid comprises(1) forming a ternary complex by the interaction of(a) the antigenic substance,(b) a first antibody which contains a kappa chain and which binds to the antigenic substance, and(c) a second antibody which binds to the kappa chain of the first antibody, said second antibody being immobilized on a solid phase carrier, and(2) separating the fluid from the solid phase carrier.
    Type: Grant
    Filed: September 4, 1990
    Date of Patent: March 2, 1993
    Assignee: Eastman Kodak Company
    Inventors: Alan R. Thomson, Frances L. Stickley, Stephen E. Clark, John L. Daiss
  • Patent number: 5161564
    Abstract: An automatically resetting mechanical valve used to control unwanted discharge of liquids less dense than water, principally oil, which may be present in waste water flows. The valve is closed by sinking both a primary float and a secondary float, each less dense than water but more dense than the liquid whose discharge is to be stopped. The sinking primary float effectively closes an orifice in an outlet conduit upon the sinking primary float's becoming sufficiently immersed in the less dense liquid. Upon the reintroduction of water, the secondary float acts upon a lever of high mechanical advantage, which pries the primary float upward, which, in turn, allows hydraulic pressure inside and outside the conduit to equalize, thereby allowing the primary float to unseat and the valve to automatically re-open.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: November 10, 1992
    Inventor: Stephen E. Clark
  • Patent number: 4838732
    Abstract: An elastomeric sealing device to prevent ingress of surface fluids into holes, principally drains which are characterized by non-watertight covers or grilles with either regular or irregular topographic boundaries. The device comprises a three-part construction, including a top film, a core elastomer having minimal shear strength, and a bottom film. When in use, the device conforms to contour of adjacent hole covering device and fills existing crevices and voids, thereby providing an efficient seal. When removed from hole, device recovers neutral shape thereby being suitable for re-use on same or different hole.
    Type: Grant
    Filed: May 12, 1982
    Date of Patent: June 13, 1989
    Inventors: Stephen E. Clark, Earl A. Clark
  • Patent number: 4807080
    Abstract: Protection of the thin gate oxide of MOS field effect transistors from irreversible puncture due to undesired high voltages and currents generated by electrostatic discharge through handling or otherwise, is provided by a circuit structure at each input pad of an integrated circuit chip. One such feature includes the use of a barrier layer of polysilicon material to make an electrical contact between source and drain diffusions of a protective transistor and their respective aluminum conductors, in order to increase the amount of current that can be handled at such contacts without the aluminum conductor fusing though a diffusion into the substrate. Another such feature is to provide an initial, and perhaps only, protective transistor that has a very narrow channel between source and drain diffusions to allow a reversible breakdown to reduce the voltage across it to within, or nearly within, the maximum voltage that the protected thin gate oxide transistor can handle without being damaged.
    Type: Grant
    Filed: June 15, 1987
    Date of Patent: February 21, 1989
    Assignee: Zilog, Inc.
    Inventor: Stephen E. Clark
  • Patent number: 4738563
    Abstract: Partially submerged, buoyant portable marine fence has netting material attached to series of float-supported longitudinally spaced upright fence poles which extend from bottom of water to above the surface of water. Floats are attached to each pole at the low water elevation on each pole. When horizontal wind or water forces are exerted upon fence, poles pivot about detachable ballasts located at the base of each pole.
    Type: Grant
    Filed: July 22, 1987
    Date of Patent: April 19, 1988
    Inventor: Stephen E. Clark
  • Patent number: 4580592
    Abstract: Open vessel separator valve has ballasted, hollow-cavitied float disposed above oil/water inlet orifice. Float having large net mass floats in water and sinks in oil. Liquid passes through spillways of sinking float into said float cavity and fills same. Sunken float applies downward force upon sealing means located thereunder, thereby closing oil/water inlet orifice. Device can be reset by draining liquid from sunken float.
    Type: Grant
    Filed: October 25, 1983
    Date of Patent: April 8, 1986
    Inventors: Stephen E. Clark, Earl A. Clark