Patents by Inventor Robert C. Prescott
Robert C. Prescott 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: 6318497Abstract: A pressure-sensitive switch comprises a base member having a mounting surface formed of electrically-insulating material; two electrodes mounted on the base member and each having an electrically-conductive contact surface, and a flexible diaphragm having its periphery secured in a fluid-tight manner to the mounting surface with its electrically-conductive central portion overlying the contact surfaces of the electrodes. The diaphragm, which is formed with plural corrugations, is exposed to the external pressure. When the switch is exposed to atmospheric pressure, the central portion of the diaphragm does not touch the contact surfaces of said electrodes, but when the switch is exposed to a super-atmospheric pressure, this central portion is forced into contact with both contact surfaces, thus electrically connecting the two electrodes. This pressure-sensitive switch is especially useful for use with hydrophones, as in seismic streamer cables.Type: GrantFiled: May 15, 2000Date of Patent: November 20, 2001Assignee: Benthos, Inc.Inventors: Thomas J. De Groot, Glen Ferguson, William H. Hulsman, Robert C. Prescott, Richard D. Smith
-
Patent number: 5655579Abstract: A method and apparatus for testing a fire suppressing system having outlet nozzles from which a high pressure suppressant agent is discharged in which a vessel is attached to each nozzle to capture the agent discharged during a test. The collection vessel is preferably an elongated plastic bag that is rolled to remove air from the bag before agent is discharged into it. The amount of agent captured in a vessel is calculated, such as by weighing. The captured discharged agent is compressed for return to a storage container in which it can be re-pressurized for further use.Type: GrantFiled: May 8, 1995Date of Patent: August 12, 1997Assignee: Kidde-Fenwal, Inc.Inventors: Robert C. Prescott, Joseph A. Senecal
-
Patent number: 5257639Abstract: A transducer having an explosion-proof housing with a divider forming two compartments, and the divider having formed therein a well. A magnet and flapper arm arrangement is suspended within the well. A coil winding is fixed in the other compartment around the well so that a magnetic field generated thereby influences the pivotal position of the magnet. Set screws adjustable in the bottom of the well are effective to preset a rest position of the magnet.Type: GrantFiled: August 24, 1992Date of Patent: November 2, 1993Assignee: Dresser Industries, Inc.Inventors: Robert C. Prescott, Donald C. Simpson, Philip H. Sanford, Howard W. Nudd
-
Patent number: 5159949Abstract: A transducer having an explosion-proof housing with a divider forming two compartments, and the divider having formed therein a well. A magnet and flapper arm arrangement is suspended within the well. A coil winding is fixed in the other compartment around the well so that a magnetic field generated thereby influences the pivotal position of the magnet. Set screws adjustable in the bottom of the well are effective to preset a rest position of the magnet.Type: GrantFiled: June 10, 1991Date of Patent: November 3, 1992Assignee: Dresser Industries, Inc.Inventors: Robert C. Prescott, Donald C. Simpson, Philip H. Sanford, Howard W. Nudd
-
Patent number: 5022425Abstract: A transducer having a cross field polarized permanent magnet mounted for slight pivotal movement within an annular coil winding. The magnet comprises neodymium-iron-boron to provide a compact, lightweight, low inertia and high intensity magnetic field. A magnetic field generated by current in the coil winding influences the permanent magnet to pivot slightly about a horizontal axis and rotate a yoke structure to produce a mechanical output of the transducer. In the preferred embodiment of the invention, the yoke is attached to a spring arm for controlling escape gas pressure from a nozzle to thereby control the pressure of a gas stream.Type: GrantFiled: March 28, 1990Date of Patent: June 11, 1991Assignee: Dresser Industries Inc.Inventors: Robert C. Prescott, Robert J. Robinson
-
Patent number: 4926896Abstract: A transducer having a cross field polarized permanent magnet mounted for slight pivotal movement within an annular coil winding. The magnet comprises neodymium-iron-boron to provide a compact, lightweight, low inertia and high intensity magnetic field. A magnetic field generated by current in the coil winding influences the permanent magnet to pivot slightly about a horizontal axis and rotate a yoke structure to produce a mechanical output of the transducer. In the preferred embodiment of the invention, the yoke is attached to a spring arm for controlling escape gas pressure from a nozzle to thereby control the pressure of a gas stream.Type: GrantFiled: December 23, 1988Date of Patent: May 22, 1990Assignee: Dresser Industries, Inc.Inventors: Robert C. Prescott, Robert J. Robinson
-
Patent number: 4492246Abstract: A transducer for converting an electrical current signal to a pneumatic pressure. A solid state element such as piezo-electric flapper element 48 is used to vary the pressure drop through a nozzle 46 to provide a controlled pressure supply 28. A micro-power electronic circuit 59 controls the flapper. A solid state pressure sensor 24 detects the output pressure and provides a feedback signal for use in a negative feedback loop to control the flapper element. The flapper element may be triangularly shaped to reduce its responsiveness to relatively low frequency mechanical vibrations. In a exemplary embodiment, where intrinsic safety requirements limit terminal voltages, the flapper element is driven by a transconductance amplifier 94 which is powered through a shunt regulator 82 and a voltage tripler 92. The shunt regulator provides operating potentials which are derived from the signal current.Type: GrantFiled: March 28, 1983Date of Patent: January 8, 1985Assignee: McGraw-Edison CompanyInventors: Robert C. Prescott, Calman Gold, Eric V. Anderson
-
Patent number: 4098592Abstract: A process chromatograph including a column for separating fluid samples into their individual components, and a density-responsive detector connected to the column output to produce a pressure signal representing the concentration of the separated components. The column and associated elements are contained within a thermally-insulated housing the interior spaces of which are heated and maintained at a set-point temperature by a temperature regulating system. Heat energy is supplied by steam to one section of a two-section tubular heat-exchanger. A stream of air is caused to flow through the other section and into the housing interior, to transfer heat thereto. The rate of heat transfer is automatically controlled by a thermostatic control which continuously adjusts the flow of air through the heat exchanger so as to maintain the interior temperature at a desired set-point.Type: GrantFiled: November 24, 1976Date of Patent: July 4, 1978Assignee: The Foxboro CompanyInventors: Robert C. Prescott, Roy P. Lindquist
-
Patent number: 4059994Abstract: An all-pneumatic process chromatograph having a pneumatically-actuated sample-injection valve, an orifice connected in the column output line to develop a pressure signal corresponding to fluid density, a pneumatic amplifier for strengthening the pressure signal, and pneumatically-operated control means for developing a periodic sample-valve actuating signal and for selecting a particular peak of interest at a controllable time following injection of the sample. The pneumatic control means includes means automatically operable to adjust the time of peak selection in response to changes in actual peak elution time. The temperature-sensitive elements of the apparatus are contained in a chamber which is heated by a source of steam heat, with the rate of heat transfer being regulated pneumatically to maintain a relatively constant temperature within the chamber.Type: GrantFiled: November 26, 1976Date of Patent: November 29, 1977Assignee: The Foxboro CompanyInventors: Raymond Annino, Robert C. Prescott, Edwin L. Karas, Richard W. Kalinoski
-
Patent number: 4006624Abstract: An all-pneumatic process chromatograph having a pneumatically-actuated sample-injection valve, an orifice connected in the column output line to develop a pressure signal corresponding to fluid density, a pneumatic amplifier for strengthening the pressure signal, and pneumatically-operated control means for developing a periodic sample-valve actuating signal and for selecting a particular peak of interest at a controllable time following injection of the sample. The pneumatic control means includes means automatically operable to adjust the time of peak selection in response to changes in actual peak elution time. The temperature-sensitive elements of the apparatus are contained in a chamber which is heated by a source of steam heat, with the rate of heat transfer being regulated pneumatically to maintain a relatively constant temperature within the chamber.Type: GrantFiled: February 14, 1975Date of Patent: February 8, 1977Assignee: The Foxboro CompanyInventors: Raymond Annino, Robert C. Prescott, Edwin L. Karas, Richard W. Kalinoski
-
Patent number: 3981318Abstract: A pneumatic output signal limiting device utilizing a planar-type construction having a balance beam with a passage extending through the area of its pivotal axis to provide communication between side-by-side chambers and arranged so that the balance beam moves into contact with a valve in the output chamber to close the passage and further movement in the same direction open a vent. In operation, the output signal equals the input signal when the input signal is within one limit of a preselected output signal operating range. When the input signal equals the limit, the passage is closed and the output signal is maintained equal to the limit. The passage remains closed when the input is outside the limit and the output signal is maintained equal to the limit until the input signal is a preselected value outside the limit. Then the balance beam moves in the same direction to open the vent and reduce the output signal to the vent pressure.Type: GrantFiled: February 3, 1975Date of Patent: September 21, 1976Assignee: The Foxboro CompanyInventor: Robert C. Prescott