Patents by Inventor James T. Dakin

James T. Dakin 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: 6798139
    Abstract: A ceramic body (14) for a discharge vessel (12) includes a central barrel portion (60) and two end plus (64, 66), which close opposite ends of the barrel. Main electrode (32, 34) and an initiator electrode 50 are supplied with power via conductors in leg members (70, 76, 72). In one embodiment, a first electrode 32 and the initiator electrode are supplied with current through two separate leg members. In another embodiment, a dual electrode leg member is provided with two bores (124, 126).
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: September 28, 2004
    Assignee: General Electric Company
    Inventors: Raghu Ramaiah, James T. Dakin
  • Patent number: 6781295
    Abstract: A lamp assembly (10) includes a body (12) having a concave reflecting surface (16) that opens toward a first or open end (18) and a neck (22) at a second end includes an opening (24). A light source (30) is received in the body adjacent the reflecting surface and has a seal or pinch region (44) which extends into the neck. A mounting clip (80) includes a plate (82) that engages the outer surface of the neck. First and second legs (84, 86) of the mounting clip engage the pinch region via teeth (88), while arms (90, 92) engage an internal surface (94) of the neck.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: August 24, 2004
    Assignee: General Electric Company
    Inventors: James T. Dakin, Matthew A. Bugenske
  • Patent number: 6731067
    Abstract: An apparatus for improving the performance of a ceramic metal halide (CMH) lamp includes an interior chamber (12) disposed within an outer envelope (10). In a preferred arrangement, two legs (14, 16) extend laterally in opposite directions from the chamber. Each leg encloses an electrode/leadwire assembly (22, 24). The electrode/leadwire assembly is constructed from a single continuous piece of wire, preferably tungsten, which forms a shaft or mandrel (50). One end of the mandrel supports an electrode tip (52) which is also preferably made from tungsten. The mandrel also supports an overwind component (54) at a predetermined position. In a desired arrangement, the overwind component is made from molybdenum. The single or one-piece mandrel negates the need for a welded shank assembly resulting in a stronger and more stable lamp that is less expensive to manufacture.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: May 4, 2004
    Assignee: General Electric Company
    Inventors: James R. Woodward, James T. Dakin
  • Patent number: 6731068
    Abstract: A metal halide lamp comprised of a ceramic discharge chamber containing an ionizable fill, said fill comprising Hg, and halides (H) of Na, TI, an alkaline earth metal, and 0>rare earth element (Re)<15 as a molar fraction.
    Type: Grant
    Filed: December 3, 2001
    Date of Patent: May 4, 2004
    Assignee: General Electric Company
    Inventors: James T. Dakin, James A. Leonard, Stuart A. Mucklejohn, Gergely Ormandlaky
  • Publication number: 20030234613
    Abstract: A ceramic body (14) for a discharge vessel (12) includes a central barrel portion (60) and two end plus (64, 66), which close opposite ends of the barrel. Main electrode (32, 34) and an initiator electrode 50 are supplied with power via conductors in leg members (70, 76, 72). In one embodiment, a first electrode 32 and the initiator electrode are supplied with current through two separate leg members. In another embodiment, a dual electrode leg member is provided with two bores (124, 126).
    Type: Application
    Filed: June 25, 2002
    Publication date: December 25, 2003
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Raghu Ramaiah, James T. Dakin
  • Publication number: 20030168959
    Abstract: A lamp assembly (10) includes a body (12) having a concave reflecting surface (16) that opens toward a first or open end (18) and a neck (22) at a second end includes an opening (24). A light source (30) is received in the body adjacent the reflecting surface and has a seal or pinch region (44) which extends into the neck. A mounting clip (80) includes a plate (82) that engages the outer surface of the neck. First and second legs (84, 86) of the mounting clip engage the pinch region via teeth (88), while arms (90, 92) engage an internal surface (94) of the neck.
    Type: Application
    Filed: December 27, 2002
    Publication date: September 11, 2003
    Applicant: General Electric Company
    Inventors: James T. Dakin, Matthew A. Bugenske
  • Publication number: 20030102808
    Abstract: A metal halide lamp comprised of a ceramic discharge chamber containing an ionizable fill, said fill comprising Hg, and halides (H) of Na, TI, an alkaline earth metal, and 0>rare earth element (Re)<15 as a molar fraction.
    Type: Application
    Filed: December 3, 2001
    Publication date: June 5, 2003
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: James T. Dakin, James A. Leonard, Stuart A. Mucklejohn, Gergely Ormandlaky
  • Patent number: 5675677
    Abstract: A lamp-to-light guide coupling arrangement includes an electrodeless high intensity discharge lamp comprising an arc tube with an ionizable fill, and an excitation circuit for electrically exciting the ionizable fill to induce therein a light-producing arc discharge. The coupling arrangement further includes a coupling device comprising a generally tubular, hollow body that has an inlet end for receiving light from the arc discharge and a larger, outlet end. The coupling device further comprises an interiorly directed reflector on a surface of the hollow body for reflecting visible light. Such coupling device is shaped so as to receive light at one solid angle over an area of the inlet end and to transmit light at a smaller solid angle but over a larger area of the outlet end. The coupling device is preferably formed from dielectric material. The reflector preferably comprises a refractory optical interference filter.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: October 7, 1997
    Assignee: General Electric Company
    Inventors: John M. Davenport, Mark E. Duffy, Richard L. Hansler, Kenneth S. King, William J. Cassarly, Thomas G. Parham, Gary R. Allen, James T. Dakin, Frederic F. Ahlgren
  • Patent number: 5610469
    Abstract: An electric lamp includes a sealed outer envelope, an arctube located within the envelope, a shroud separate from the arctube having an ellipsoidally-shaped reflecting portion positioned around the arctube, and a coating disposed on the reflecting section of the shroud for reflecting light having predetermined wavelengths emitted by the arctube. The ellipsoidal shape of the shroud is effective for reflecting the light substantially back toward the arctube. Particularly when the coating is a color correcting coating, the shape of the reflecting section is tailored to maximize reflection of radiation at selected wavelengths back toward the arc of the arctube.
    Type: Grant
    Filed: March 16, 1995
    Date of Patent: March 11, 1997
    Assignee: General Electric Company
    Inventors: Rolf S. Bergman, James T. Dakin, Thomas G. Parham
  • Patent number: 5479072
    Abstract: A high intensity metal halide arc discharge lamp, such as an electrodeless lamp wherein RF energy is inductively coupled to the arc discharge, contains a halide of neodymium alone or in combination with other metals such as one or more rare earth metals, Na, Cs and is essentially mercury free (i.e., <1 mg per cc of arc chamber volume).
    Type: Grant
    Filed: November 12, 1991
    Date of Patent: December 26, 1995
    Assignee: General Electric Company
    Inventors: James T. Dakin, Tommie Berry, Jr., Mark E. Duffy, Timothy D. Russell
  • Patent number: 5378965
    Abstract: An electrodeless discharge lamp comprising an arc tube constructed of a light-transmissive material. An exciting structure surrounds the arc tube and is energizable with radio frequency current to develop an arc discharge. A reflective coating of non-conducting insulating material is disposed on the arc tube wall and is located to reflect light from the arc discharge through the arc tube. The reflective coating and the uncoated portion of the arc tube wall are surrounded by the exciting structure so that light from the arc discharge may reach the reflective coating without blockage by the exciting structure and, following reflection by the coating, travel through the uncoated portion of the arc tube wall.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: January 3, 1995
    Assignee: General Electric Company
    Inventors: James T. Dakin, Lawrence W. Speaker, Mark E. Duffy, Raymond A. Heindl
  • Patent number: 5373216
    Abstract: An electrodeless high intensity discharge (HID) lamp arc tube having a stabilized condensate location. The arc tube contains a predetermined location or distortion on the inside surface of the arc tube. The distortion may be a protrusion on the inside surface of the arc tube formed during the arc tube forming process. In operation of the lamp, the non gaseous dose remains condensed substantially in the cold spot region formed by said protrusion so that the arc tube walls remain clear for maximal light output, and the arc tube remains stable and efficacious to substantially higher power than is the case for arc tubes without the distortion.
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: December 13, 1994
    Assignee: General Electric Company
    Inventors: James T. Dakin, Mark E. Duffy
  • Patent number: 5363015
    Abstract: A high intensity electrodeless metal halide arc discharge lamp wherein RF energy is coupled to the arc discharge, contains a halide of praseodymium alone or in combination with other metals such as one or more rare earth metals, Na and Cs and is essentially mercury free (i.e., < 1 mg per cc of arc chamber volume).
    Type: Grant
    Filed: August 10, 1992
    Date of Patent: November 8, 1994
    Assignee: General Electric Company
    Inventors: James T. Dakin, Tommie Berry, Jr., Mark E. Duffy, Timothy D. Russell
  • Patent number: 5306987
    Abstract: An arc stabilization arrangement for a discharge lamp having a light transmissive arc tube containing a fill of gas excitable to a discharge state upon introduction thereto of a drive signal having a predetermined frequency associated therewith, includes a modulating arrangement effective for providing a modulating signal which is imposed onto the drive signal. The modulating signal has a frequency associated therewith which approximates the acoustic resonance of the gases within the fill, such modulating signal frequency being less than the frequency of the drive signal. In one embodiment of the invention the modulating arrangement is an amplitude modulating scheme effective such that a modulating amplitude of greater than about 5% of the amplitude of the drive signal is achieved. In yet a further implementation of the present invention, the frequency of the modulating signal is swept about a range of frequencies so that a varying acoustic resonance frequency can be encompassed by the modulating signal.
    Type: Grant
    Filed: March 11, 1993
    Date of Patent: April 26, 1994
    Assignee: General Electric Company
    Inventors: James T. Dakin, Mark E. Duffy
  • Patent number: 5258691
    Abstract: Asymmetric discharge electrode means are provided for a metal halide lamp enabling improved operation at acoustic frequencies. A xenon-metal halide lamp employing such improved discharge electrode means is disclosed together with a reflector lamp unit employing such lamp construction for its light source.
    Type: Grant
    Filed: June 10, 1992
    Date of Patent: November 2, 1993
    Assignee: General Electric Company
    Inventors: James T. Dakin, Kenneth S. King, Gary R. Allen
  • Patent number: 5248918
    Abstract: This electrodeless high intensity discharge lamp including a light-transmissive arc tube having spaced wall portions of dielectric material and a first gaseous fill within the arc tube. An excitation coil about the arc tube is energizable with RF current effective to develop a toroidal arc discharge in the first gaseous fill upon a dielectric breakdown of the fill. A starting container is joined to the arc tube and has an end wall constituted by one of said arc-tube wall portions. A second gaseous fill within the starting container has a dielectric strength lower than that of the first gaseous fill. For initiating the rotoidal arc discharge, we provide an arrangement for producing a dielectric breakdown of the gaseous fill within the starting container that develops into an electric discharge that changes the potential at the end wall in such a manner as to cause a dielectric breakdown of the first gaseous fill.
    Type: Grant
    Filed: April 9, 1992
    Date of Patent: September 28, 1993
    Assignee: General Electric Company
    Inventors: James T. Dakin, Mark E. Duffy, Raymond A. Heindl
  • Patent number: 5213537
    Abstract: After evacuating and cleaning a discharge lamp, such as a fluorescent lamp, the lamp is dosed with mercury in the vapor phase. In particular, mercury vapor is introduced into the lamp at a predetermined pressure such that the vapor contained within the lamp corresponds to the required amount of mercury. To this end, the vapor pressure of mercury is controlled by controlling the temperature of the lamp and a reservoir of mercury in a pre-filled mercury container. Alternatively, a pressure regulator is used to directly control the vapor pressure of mercury at a sufficiently high temperature to maintain at least a portion of the mercury in the vapor state. Still another alternative method involves metering a fixed volume of mercury at a predetermined pressure. Finally, the discharge lamp is dosed with the remaining fill ingredients, e.g., at least one inert gas for a fluorescent lamp.
    Type: Grant
    Filed: June 25, 1992
    Date of Patent: May 25, 1993
    Assignee: General Electric Company
    Inventors: Victor D. Roberts, James T. Dakin, Walter R. Champman, Jr., Bernard F. Fenoglio
  • Patent number: 5214357
    Abstract: A low-loss L-C circuit arrangement for an electrodeless high intensity discharge (HID) lamp includes an excitation coil having at least one coil turn which is disposed in surrounding relation to the arc tube portion of the HID lamp and is configured in a low profile manner so as to minimize light blockage caused thereby. The L-C circuit arrangement includes a capacitor member having first and second capacitor plates which are electrically and mechanically connected to the excitation coil. The connection between the excitation coil and the capacitor member is made by a pair of connection members integrally formed with the coil turn and capacitor plates from a stock sheet of electrically and thermally conductive material.
    Type: Grant
    Filed: November 14, 1991
    Date of Patent: May 25, 1993
    Assignee: General Electric Company
    Inventors: James T. Dakin, Mark E. Duffy, Raymond A. Heindl, Victor A. Levand, Jr.
  • Patent number: 5151633
    Abstract: The fill of a self-extinguishing gas probe starter for an electrodeless high intensity discharge lamp includes a starter fill component which has a relatively low vapor pressure and is substantially inert in the starter fill at ambient temperatures, but which component vaporizes and becomes electronegative as the temperature of the lamp increases, so that the starter fill component attaches electrons of the starting discharge in the gas probe starter and thereby extinguishes the starting discharge after initiation of the arc discharge in the arc tube. As a result, the flow of currents between the gas probe starter and the arc tube, which would otherwise have a detrimental effect on the arc tube wall, is avoided.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: September 29, 1992
    Assignee: General Electric Company
    Inventors: George A. Farrall, John P. Cocoma, James T. Dakin, Mark E. Duffy, Tommie Berry, Jr.
  • Patent number: 5150015
    Abstract: An electrodeless high intensity discharge (HID) lamp having an arc tube, a starting aid, and an outer jacket all integrally formed of fused quartz, includes an excitation circuit for providing RF energy effective for initiating and maintaining a gas discharge within the arc tube. The arc tube is positioned within the outer jacket such that a minimum space exists between the outer jacket and the arc tube thereby allowing the efficient coupling of such RF energy to the arc tube by means of an excitation coil wound in close proximate location to the arc tube. The starting aid is of a substantially smaller dimension than the arc tube thereby allowing for a second spacing to occur above the arc tube. This second spacing is effective for optimum thermal management of heat generated within the outer jacket. The upper end of the outer jacket has an integrally formed annular groove for receiving an annular support member effective for securing the HID lamp to a lighting fixture.
    Type: Grant
    Filed: April 15, 1991
    Date of Patent: September 22, 1992
    Assignee: General Electric Company
    Inventors: Raymond A. Heindl, Mark E. Duffy, James T. Dakin, Harald L. Witting, Richard C. Nagle, Lawrence T. Mazza