Patents by Inventor Donald M. Cunningham

Donald M. Cunningham 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: 6668136
    Abstract: An integral heating and cooling unit is disclosed. The integral heating and cooling unit controls the temperature of a working fluid by heating or cooling the fluid either independently or in tandem. The integral heating and cooling unit includes a casing or outer housing, which defines a plenum. A heat exchanger pipe is attached to the outer housing and passes through the plenum. A plurality of heating elements connects to the outer housing and extends into the plenum. The heating elements heat the working fluid when they are powered and the working fluid passes through the plenum. The heat exchanger pipe extracts heat from the working fluid when a cooling fluid passes through the pipe and in heat transfer relation with the working fluid.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: December 23, 2003
    Assignee: Chromalox, Inc.
    Inventors: Sam W. Henry, Paul Neilson, Randy C. Jarrett, Steven U. Nestel, Donald M. Cunningham
  • Patent number: 6191400
    Abstract: A metal sheath heating element for substantially dry applications is disclosed. In one embodiment, the heater is substantially elongate and cylindrical, and comprises a coiled resistive heater wire. The heater wire is disposed within a stainless steel outer sheath. Granular insulating material is introduced into the sheath to electrically insulate the heating element from the outer sheath, and to thermally conduct heat from the heating element to the sheath. At least one small hole is formed in outer sheath to permit any moisture trapped therein to escape, advantageously minimizing the potential for current leakage between the heating element and the outer sheath, as well as minimizing the likelihood of depletion of oxygen from the filler material due to oxidation occurring within the sheath. In one embodiment, a plurality of holes are formed at spaced intervals along the length of the sheath.
    Type: Grant
    Filed: October 21, 1999
    Date of Patent: February 20, 2001
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 5243903
    Abstract: The present invention discloses a compactor for recyclable containers that uses gravity instead of brute force to compact recyclable containers. An upper section slides over a lower section. A recyclable container is placed on top of the lower section. The user applies his or her weight to the upper section. As the upper section approaches the lower section, the recyclable container is compacted.
    Type: Grant
    Filed: August 6, 1992
    Date of Patent: September 14, 1993
    Inventors: Michael A. Blackmer, Donald M. Cunningham, Frank L. Bumbalough
  • Patent number: 5220155
    Abstract: An electric range (R) has a glass/ceramic cooking top (S) upon which rests a cooking utensil. Electrical heating apparatus (10) has an electrical resistance heating element (12) to which an electrical current is supplied. This causes the heating element to generate heat. A heat sink (16) is interposed between the heating element and the cooking top for absorbing heat energy from the heating element and for spreading the energy under the surface area of the top by conduction. The heat sink is of an electrically insulative, translucent, aluminum nitride material or similar high thermal conductivity material. An insulation cake (20) supports the heating element and heat sink adjacent an underside of the cooking top and provides both electrical and thermal insulation. A pan (24) supports the insulation cake, the heating element (12) and the sink (16) in intimate contact with each other and the underside of the cooking top for maximum heat transfer by conduction.
    Type: Grant
    Filed: March 12, 1992
    Date of Patent: June 15, 1993
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4900897
    Abstract: In a metallic sheathed electric heating element assembly having a resistance element, a sheath surrounding the resistance element, pulverulent electrically insulating material within the sheath and surrounding the resistance element, the insulating material being tightly compacted and extending within the sheath short of an open end thereof, and a terminal pin electrically and mechanically connected to an end of the resistance element within the compass of the sheath, the terminal pin is made in two parts, an inner part to which the resistance element is connected, and an outer part spaced from the inner part, and a thermal switch or cut off electrically connected to and in series between the inner and outer parts of the pin within the sheath but spaced toward the open end from the compacted insulating material, the thermal switch being in good thermal contact with the inner part of the terminal pin.
    Type: Grant
    Filed: November 21, 1988
    Date of Patent: February 13, 1990
    Assignee: Emerson Electric Co.
    Inventors: Donald M. Cunningham, Mark A. Bartels, T. Randall Markum
  • Patent number: 4879453
    Abstract: A self-regulating heat producing strip is disposed along each wall of a room. The strip includes at least one pair of spaced apart electrical conductors extending longitudinally along the base of at least one wall and spaced therefrom. Self-limiting conductive material is in physical contact with and forms a heat generating zone between the conductors. An electrically insulated jacket longitudinally covers the conductors and the self-limiting conductive material. Connectors are provided for connecting the conductors to a power source to generate heat in the heat generating zone between the conductors.
    Type: Grant
    Filed: June 10, 1987
    Date of Patent: November 7, 1989
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4733055
    Abstract: An electric heating element with a resistance element, a metal sheath in heat transfer relation to the resistance element on one side of the sheath and a thin, dry coating of refractory material major proportion by weight of which is boron nitride on another side of the sheath to be placed in heat transfer relation to an object to be heated. A method of enhancing the heat-transfer qualities of a metal sheathed electric heating element includes coating the metal sheath, on a surface to be placed in heat-transfer relation to an object to be heated, with a liquid slurry of refractory material a major proportion of which is boron nitride, drying and outgassing the coating and mounting the sheathed element on an object to be heated with the coating in contact with the object.
    Type: Grant
    Filed: August 25, 1986
    Date of Patent: March 22, 1988
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4689470
    Abstract: A self-regulating heat producing strip is disposed along each wall of a room. The strip includes at least one pair of spaced apart electrical conductors extending longitudinally along the base of at least one wall and spaced therefrom. Self-limiting conductive material is in physical contact with and forms a heat generating zone between the conductors. An electrically insulated jacket longitudinally covers the conductors and the self-limiting conductive material. Connectors are provided for connecting the conductors to a power source to generate heat in the heat generating zone between the conductors.
    Type: Grant
    Filed: February 18, 1986
    Date of Patent: August 25, 1987
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4687905
    Abstract: A water heater with a plastic tank is provided with an electric immersion heating element assembly having a mounting plug in which is mounted a sheathed heating element having two generally parallel legs and a bight portion. A well projects from the mounting plug along and substantially parallel to the legs in heat exchange relation therewith and contains a thermal cutoff adapted to be electrically connected in series with the first end of a two-ended electric resistance element in the sheathed heating element. A thermally conductive bridge mechanically and thermally connects the legs of the sheathed heating element to the well. The legs of the sheathed heating element are bent back upon themselves and a bracket, connected to the two reaches of at least one leg, permits relative axial movement but prevents lateral movement of the reaches of the legs with respect to one another. The mounting plug is made of solid copper or copper alloy, as is the sheath and well.
    Type: Grant
    Filed: February 3, 1986
    Date of Patent: August 18, 1987
    Assignee: Emerson Electric Co.
    Inventors: Donald M. Cunningham, Mark A. Bartels, T. Randall Markum
  • Patent number: 4650972
    Abstract: A heating cable includes a pair of spaced apart electrical conductors extending the length of the cable. A matrix of filled polymeric material in physical contact with the conductors forms a heat generating web therebetween. The filled polymeric material has a volume resistivity selected to provide a predetermined heat output per unit length of cable. A plurality of macroscopic perforations are punched through the web between the two conductors so that the actual heat output per unit length of cable is a desired value less than the predetermined heat output per unit length. An electrically insulative jacket longitudinally covers the conductors and the web.
    Type: Grant
    Filed: October 4, 1985
    Date of Patent: March 17, 1987
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4543469
    Abstract: An electric metallic sheathed immersion heating element adapted to be mounted on the metal wall of a fluid tank with the active heating portion of the element extending through an opening in the tank wall into the contents thereof includes a rigid plastic mounting member fixed to the terminal portion of the heating element and adapted to be connected to the tank wall at the opening to operatively support the heating element on the tank. The rigid plastic mounting member may be formed as a molded plastic plug having an exterior screw thread adapted to engage a cooperative screw thread on the tank wall or as a flat plate adapted to be bolted to the exterior surface of the tank wall. In order to reduce corrosive erosion of the heating element sheath, the sheath is grounded to the metal tank wall by a U-shaped grounding member formed of a thin-gauge cold-rolled steel.
    Type: Grant
    Filed: April 26, 1982
    Date of Patent: September 24, 1985
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4468556
    Abstract: The electric heater herein disclosed is particularly adapted to heat a fluid and to provide a broad, substantially flat heater surface exposed to the fluid to be heated. The heating element is well adapted for deep fat frying use in that it is of high voltage and is economical to manufacture. The invention makes use of standard elongated, tubular, metal-sheathed heaters which are produced in large quantities for a multitude of uses. Such elements are slid into a metal tube of selected diameter and wall thickness, and the assembly is flat-pressed in appropriate sections with the ends round for termination with such fittings as are required. The assembly may then be bent to produce a desired configuration.
    Type: Grant
    Filed: August 9, 1982
    Date of Patent: August 28, 1984
    Assignee: Emerson Electric Co.
    Inventors: Donald M. Cunningham, John C. Stover
  • Patent number: 4395618
    Abstract: A circulation heater for heating a fluid, particularly a liquid such as oil, includes an imperforate heavy-duty steel tubular body closed at both ends and having internal vanes establishing a plurality of separated longitudinally - extending chambers therein. The vanes are ported to establish a fluid flow path serially through the chambers from an inlet communicating with a first chamber to an outlet communicating with a last chamber. One or more metal-sheathed electric heating elements are located within each chamber and the chambers and heating elements therein are so arranged and designed, for example, by making the chambers of uniform transverse cross-sectional area and placing different numbers of heating elements of identical transverse cross-sectional area in each chamber, that the velocity of the fluid increases as it flows from the inlet to the outlet.
    Type: Grant
    Filed: March 3, 1980
    Date of Patent: July 26, 1983
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4319127
    Abstract: Electric heating elements, particularly adapted for use in solder pots or in other uses wherein a substance is to be maintained in a molten or plastic condition, and commonly termed in such uses as over-the-side heaters. A conventional tubular heater is disposed within the central opening of a thick-wall metal pipe or tube, and the latter is swaged to reduce its cross-sectional size and thereby fit tightly about the tubular heater. Thereafter, the pipe and the heater therein, are bent in a pipe bender to any desired shape.
    Type: Grant
    Filed: July 16, 1980
    Date of Patent: March 9, 1982
    Assignee: Emerson Electric Co.
    Inventors: John A. Lindstrom, Donald M. Cunningham
  • Patent number: 4214150
    Abstract: An electric heating element for the top panel of a cooking stove, having terminals adapted to be plugged into a terminal block carried by the stove panel, and embodying means for automatically interrupting current flow to the heating element when a cooking utensil is removed therefrom. The means for automatically interrupting the current flow comprises a weight responsive switch with at least one contact in the terminal block.
    Type: Grant
    Filed: May 10, 1978
    Date of Patent: July 22, 1980
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4178497
    Abstract: A terminal end seal for a metal-sheathed electric immersion water heating element of a water heating tank includes a plastic sealing plug disposed within a pocket at the end of the sheath in surrounding relationship to the terminal pin and locked in sealing engagement with the sheath by inward deformation of the sheath. An electrically insulative vulcanized fibre washer is disposed in the pocket inwardly of the plug in engagement with the terminal pin and inner surface of the sheath. Without the fibre washer, it would be possible under abnormal conditions for the plastic sealing plug to fail and the sheath portion immersed within the water in the tank to fracture, allowing water to enter the sheath and flow outwardly of the then-open sheath end to cause damage. However, the fibre washer intercepts such water and swells to form a tight seal to restrict flow of water outwardly of the sheath.
    Type: Grant
    Filed: June 10, 1977
    Date of Patent: December 11, 1979
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 4010350
    Abstract: An electric heating element of the metal sheathed type, particularly a range surface unit comprising a spiralled metal tube having one closed end and containing compacted refractory insulation material and a helical coil of resistor alloy insulated from the tube and connected at one end to a center return conductor and having both electrical terminations extending from the other end of the tube, the construction being such that in the event of failure of the heating element, the failure will be in a passive manner.
    Type: Grant
    Filed: June 16, 1976
    Date of Patent: March 1, 1977
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 3943328
    Abstract: An electric heating element, comprising a tubular sheath formed of a thermoplastic material, an electric resistance element, such as a helical coil of resistance wire within the sheath, compacted refractory material within the sheath to hold the resistance element substantially centered within the sheath and out of engagement with the inner wall surface of the sheath, and means for mounting the sheath to a support wherein the active heating portion of the element is disposed in an environment which is controlled to maintain the sheath temperature below its melting point.The invention is particularly suited to heat liquids wherein the active heating portion is immersed in the liquid. The mounting means may also be formed of thermoplastic material and may have a terminal block integral therewith or, if a separate terminal block is used, this may be formed of a compatible thermoplastic material. The assembly of the thermoplastic parts may be effected by adhesive, heat sealing or sonic welding.
    Type: Grant
    Filed: December 11, 1974
    Date of Patent: March 9, 1976
    Assignee: Emerson Electric Co.
    Inventor: Donald M. Cunningham
  • Patent number: 3934116
    Abstract: The heater assembly comprises a sheathed electric heating element and an elastomeric bushing within a sheath end opening. A mounting flange is rigidly secured to the sheath inwardly of an end, and the bushing is held under longitudinal compression at the time the mounting flange is secured to the sheath.
    Type: Grant
    Filed: October 23, 1974
    Date of Patent: January 20, 1976
    Assignee: Emerson Electric Co.
    Inventors: Donald M. Cunningham, Ralph Santoro
  • Patent number: D263734
    Type: Grant
    Filed: March 24, 1980
    Date of Patent: April 6, 1982
    Assignee: Emerson Electric Co.
    Inventors: Donald M. Cunningham, Richard W. Brent, John C. Stover