Patents Assigned to Electrostatic Technology, Inc.
  • Patent number: 6017381
    Abstract: Collection of particles from a gas stream and the separation of dissimilar particles from a gas stream by a field effect auxiliary gas cyclone (FEAGC) is enhanced by providing an inductive field that attracts or repels particles and an auxiliary gas system that complements the field effect by providing an additional independent internal control for particle velocity, particle concentration, and system delta p. The FEAGC has three adjustable operating variables: (1) an auxiliary high pressure air input orifice located in the cyclone input which is used to increase the product velocity while reducing the solids to gas ratio; (2) an electric field between the cone and the vortex that subjects charged particles to either an attractive or repelling field; and (3) an auxiliary air venturi located in the inlet of the vortex to control the delta p and to control the operating temperature of the vortex and insulating materials.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: January 25, 2000
    Assignee: Advance Electrostatic Technologies, Inc.
    Inventors: John P. Dunn, Henri DeMoras
  • Patent number: 5639307
    Abstract: A fiber bundle workpiece is coated with a particulate material during passage about a plurality of pulleys arranged to establish a serpentine travel path portion through a coating zone. The pulleys have arcuate grooves extending thereabout, which cause the fiber bundle to twist axially, and the fibers of the bundle move with respect to one another as the fiber bundle moves along the serpentine path. These two actions increase coating efficiency and the penetration of particulate material into the fiber bundle. The travel path portion will preferably lie in a horizontal plane, and the coating unit will normally constitute an electrostatic fluidized bed of particulate material. After exiting the coating zone, the fiber bundle may pass through an oven to partially melt the particulate material, and thereby cause the particles to adhesively attach to the fiber bundle.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: June 17, 1997
    Assignee: Electrostatic Technology, Inc.
    Inventor: David J. Bellemare
  • Patent number: 5570789
    Abstract: An electrostatic sieve having a circular solid electrode, preferably with sawtooth contours arranged on its lower side concentrically around a center hole. The solid electrode is supported by insulating brackets around its perimeter. The brackets are attached to a conical outer structure, which also serves to collect the coarse particles. Underneath the solid electrode, with a gap between, is the sieve electrode, which is supported by a stretcher, preferably a circular ring of tubing with a square cross-section, itself supported on insulating brackets, which rest on an inner cone. The inner cone tapers toward the bottom to collect the fine powder passing through the sieve electrode, which passes through the hole in the bottom of the cone and falls into a collecting tray. The outer surface of the inner cone forms the inner surface of a conical passage, the outer surface of which is the outer conical support. Powder to be sieved is fed into the opening in the center of the solid electrode.
    Type: Grant
    Filed: October 3, 1995
    Date of Patent: November 5, 1996
    Assignee: Advanced Electrostatic Technologies, Inc.
    Inventor: John P. Dunn
  • Patent number: 5551642
    Abstract: This invention utilizes the oscillation which is produced in a powder which is acted upon by an electrostatic field. The disperser accomplishes its task by electrically charging the powder in a high voltage DC filed or by contact with a charging electrode, this causes the powder to become polarized and repel or disperse into discrete particles. The passing of particles from one electrode toward a second of opposite polarity will place a charge on the particle which causes oscillation, dispersion and movement toward the second electrode. Additional dispersion of the powder takes place as the particles oscillate and impact against the electrodes during the decent through the apparatus. Particle oscillation is related to particle polarity changes that occur as the particles traverse through the system.
    Type: Grant
    Filed: November 17, 1993
    Date of Patent: September 3, 1996
    Assignee: Advanced Electrostatic Technologies, Inc.
    Inventor: John P. Dunn
  • Patent number: 5484061
    Abstract: An apparatus for classifying particles by size comprising: a source of direct potential having first and second terminals, a sieve electrode connected to the first terminal, a solid electrode connected to the second terminal. Particles are fed to a transfer point located between the sieve electrode and the solid electrode such that the particles disperse and oscillate between the sieve electrode and the solid electrode whereby smaller particles pass through the sieve electrode. The new equipment has five adjustable operating parameters, screen angle, spacing between electrodes, field strength, powder input rate and electrode taper. The taper between electrodes is usually small, 0.3 to 0.4 of a degree with the larger opening at the top. The taper is used when the input powder is fine and the particle size differential is skewed either towards the high or low side. The purpose of the taper is to reduce the possibility of arcing at the input as well as to control dispersion of the particles.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: January 16, 1996
    Assignee: Advanced Electrostatic Technologies, Inc.
    Inventor: John P. Dunn
  • Patent number: 5395430
    Abstract: An electrostatic precipitator assembly is disclosed. The assembly includes a tubular collector and an electrode suspended therein. The electrode includes a substantially cylindrical collector portion and a charging portion which includes a rod and a charging disk, wherein the gap between the charging disk and the collector is at least as great as the gap between the collector portion of the electrode and the collector.
    Type: Grant
    Filed: July 18, 1994
    Date of Patent: March 7, 1995
    Assignee: Wet Electrostatic Technology, Inc.
    Inventors: Dale A. Lundgren, Virgil A. Marple, Robert A. Herrick
  • Patent number: 5275849
    Abstract: The apparatus, system and method utilize sequential sprays of wet, low-temperature steam, and dry, high-temperature steam to clean the exterior of laminated objects as well as to effect volatilization of liquid contaminates trapped between lamina thereof. Water is injected into the conduit through which the low-temperature steam is delivered, so as to produce a desirable concentration of droplets therein. A conveyor moves the laminated objects along a horizontal path through zones in which they are sprayed by the low temperature and high temperature steam, and then through a zone in which they are electrostatically coated with powder.
    Type: Grant
    Filed: April 21, 1992
    Date of Patent: January 4, 1994
    Assignee: Electrostatic Technology, Inc.
    Inventors: Daniel Castelli, John Donahue, Donald J. Gillette, Bedrich Hajek
  • Patent number: 5242718
    Abstract: An apparatus and method for coating surfaces of workpieces employs an electrostatic fluidized bed unit for producing a cloud of charged particles, for deposition upon the workpiece, and a second fluidized bed for agitating the particulate material and for facilitating feeding thereof to the electrostatic coating bed, the second bed being disposed beneath the first bed, and being in powder flow communication with it.
    Type: Grant
    Filed: August 20, 1991
    Date of Patent: September 7, 1993
    Assignee: Electrostatic Technology, Inc.
    Inventors: Donald J. Gillette, Bedrich Hajek
  • Patent number: 5213847
    Abstract: Electrostatic fluidized bed coating apparatus consists of an horizontal porous plate and a contiguous, vertical porous plate. Charged particles exiting the bed formed on the horizontal plate fall past the outer surface of the vertical plate, and are electrostatically recharged by ionized air issuing through it, thereby effectively extending the operative vertical length of the bed and substantially increasing coating efficiency.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: May 25, 1993
    Assignee: Electrostatic Technology, Inc.
    Inventor: Bedrich Hajek
  • Patent number: 5116636
    Abstract: The method utilizies steam to clean the exterior of laminated objects, preliminary to electrostatic powder coating, as well as to effect volatilization of liquid contaminates trapped between lamina thereof. Off-gassing that would otherwise occur when the objects are heated to effect fusion of the powder deposit is thereby avoided.
    Type: Grant
    Filed: August 9, 1991
    Date of Patent: May 26, 1992
    Assignee: S.L. Electrostatic Technology, Inc.
    Inventors: Bedrich Hajek, Donald J. Gillette
  • Patent number: 5092267
    Abstract: Apparatus for collecting and drying powder used for electrostatic coating of a workpiece has air injection means incorporated into the collection bin both to dry and also to homogenize powder recovered, just prior to withdrawal from the bin.
    Type: Grant
    Filed: June 15, 1990
    Date of Patent: March 3, 1992
    Assignee: S. L. Electrostatic Technology, Inc.
    Inventor: Bedrich Hajek
  • Patent number: 5052332
    Abstract: The apparatus and system utilize sprays of steam to clean the exterior or laminated objects, preliminary to electrostatic powder coating, as well as to effect volatilization of liquid contaminates trapped between lamina thereof. Off-gassing that would otherwise occur when the objects are heated to effect fusion of the powder deposit is thereby avoided. The apparatus includes a conveyor for transporting a workpiece along a horizontal travel path through a chamber, above and below which path a spray compartment and collecting compartment are defined, respectively.
    Type: Grant
    Filed: March 15, 1990
    Date of Patent: October 1, 1991
    Assignee: S. L. Electrostatic Technology, Inc.
    Inventors: Bedrich Hajek, Donald J. Gillette
  • Patent number: 5041301
    Abstract: Apparatus and method for coating interior surfaces of objects employs an electrostatic fluidized bed unit in which the fluidization chamber is relatively shallow, and is circumscribed by a marginal portion that conforms closely to the dimensions and configuration of the cavity of the object. The apparatus employs, as a feature of its recovery and recirculation system, a fluidized bed for agitating and facilitating feeding of the particulate material, thus making the system especially well suited for depositing coatings of abrasive materials, such as vitreous frit.
    Type: Grant
    Filed: February 7, 1990
    Date of Patent: August 20, 1991
    Assignee: S. L. Electrostatic Technology, Inc.
    Inventors: Donald J. Gillette, Bedrich Hajek
  • Patent number: 4950497
    Abstract: Electrostatic apparatus and method for coating interior surfaces of objects. The apparatus employs a fluidized bed unit in which the fluidization chamber is relatively shallow, and is circumscribed by a marginal portion that conforms closely to the dimensions and configurations of the cavity of the object. The apparatus employs a non-vacuumized powder recovery and recirculation system, and provides a peripheral slot in the marginal portion of the housing for entry of undeposited powder. Coating inside corners of objects is effectively achieved using the method of the invention, and heavy, uniform builds of the particulate material are produced efficiently and at high rates.
    Type: Grant
    Filed: June 15, 1989
    Date of Patent: August 21, 1990
    Assignee: S.L. Electrostatic Technology, Inc.
    Inventors: Donald J. Gillette, Bedrich Hajek
  • Patent number: RE35879
    Abstract: The apparatus, system and method utilize sequential sprays of wet, low-temperature steam, and dry, high-temperature steam to clean the exterior of laminated objects as well as to effect volatilization of liquid contaminates trapped between lamina thereof. Water is injected into the conduit through which the low-temperature steam is delivered, so as to produce a desirable concentration of droplets therein. A conveyor moves the laminated objects along a horizontal path through zones in which they are sprayed by the low temperature and high temperature steam, and then through a zone in which they are electrostatically coated with powder.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: August 25, 1998
    Assignee: Electrostatic Technology, Inc.
    Inventors: Daniel Castelli, John Donahue, Donald J. Gillette, Bedrich Hajek