Patents Assigned to Damper Design, Inc.
  • Patent number: 5427314
    Abstract: An apparatus and method for delivery of particulate fuel eliminates the problem of dense phase flow. The problem stems from the formation of undesirable streams of densely concentrated fuel particles, which streams have a deleterious effect on the combustion. In the distribution method and apparatus of the invention, the particulate fuel is induced to follow a different flow path from that of its transport air, as the fuel and transport air pass through the distribution device. The pattern and density of distribution of particulate fuel in the transport air then becomes controlled by the reentrainment of the fuel into the transport air rather than by flow characteristics of the fuel and transport air entering the nozzle. In the distribution device of the invention, the fuel particles are moved in a direction axially away from the furnace and into a space having a reflector wall against which the fuel particles impinge in a rebounding action.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: June 27, 1995
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hagar
  • Patent number: 5363903
    Abstract: An air heater perimeter seal provides independent positive control of the leak path induced by relative radial and axial movements at the rotor perimeter. A seal member with a relatively wide seal face disposed in a plane perpendicular to the air heater axis allows the seal member to stay within the radial width of the corresponding seat during expansion and contraction of the rotor as it moves from the air side to the discharge gas side and back. In addition, the installation adjustability and the tolerance for radial error of the seal of the present invention makes it possible for out-of-round rotors and warped housings to be properly sealed. An axial slip joint between the seal member and the rotor allows the seal face to remain adjacent to the face of the sector place and to the seat face regardless of rotor droop. The axial slip joint also acts as a labyrinth seal to control leakage of gasses between the housing and rotor.
    Type: Grant
    Filed: July 19, 1993
    Date of Patent: November 15, 1994
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hagar
  • Patent number: 5302115
    Abstract: Disclosed is a burner register assembly having an air register assembly for imparting a controlled vortex swirl to secondary combustion air of a furnace in order to entrain the fuel and primary air of the furnace and carry them into the furnace interior. The assembly may comprise a series of arcuate vanes circumferentially spaced about the fuel and primary air nozzle, the vanes being designed to induce both turbulence and a well defined vortex to the secondary air flow. A separate air valve, such as a butterfly valve, is provided upstream of the air register assembly to regulate the volume of secondary air flow. Shadow vanes may also be provided in the vicinity of the air register assembly outlet, and positioned adjacent the furnace walls in order to protect the air register assembly from furnace heat, particularly when the burner associated with the air register assembly is idle and the secondary air flow is lowered.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: April 12, 1994
    Assignee: Damper Design, Inc.
    Inventors: Donald K. Hagar, Lyle D. Geiger
  • Patent number: 5211705
    Abstract: An air register apparatus, method, and arrangement is disclosed in which each air register includes two portions, one of which feeds combustion air to an inner, ignition zone where fuel is first ignited, the other of which feeds combustion air to an outer, supplemental zone where the main combustion takes place. These two register portions provide separate and discrete air streams having measurable characteristics which accurately reflect the characteristics of the overall flow through each register portion and which characteristics govern combustion characteristics in the associated zone. Each air stream passes through an inwardly spiralling scroll passageway having a simple upstream air valve at the entrance to the passageway for controlling the flow of air through the passageway. This upstream air valve is remote from the hostile environment of the furnace or other combustion device.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: May 18, 1993
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hagar
  • Patent number: 5038849
    Abstract: A sealing structure for an air preheater is provided for maintaining a constant clearance between the drum and deformable sector plates. Deflection governing struts or beams extend across the sector plates and bend in a manner which corresponds with the change in shape which the drum undergoes when its temperature changes. The outer ends of the struts are connected to an outer ring engaged with the drum via guides. As the drum deforms so that its ends assume approximately partial spherical curvatures in response to increased temperatures, the struts are likewise deformed. The deformation of the sector plates is controlled by the more rigid struts.
    Type: Grant
    Filed: October 24, 1989
    Date of Patent: August 13, 1991
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hagar
  • Patent number: 4666270
    Abstract: An apparatus is disclosed for controlling the flow of a hot fluid. The apparatus includes a closure member for sliding between a closed position and an open position. The closure member has a hot section defined by the portion of the closure which is subject to impingement of hot fluid when the closure member is in the closed position and a cold section disposed outside the fluid passageway and not subject to impingement of hot fluids. The cold section includes at least one cleft which facilitates expansion of the cold section in response to expansion of the hot section due to heating by impingement of hot fluid on the hot section. This, in turn, relieves stresses and reduces the extent of distortion of the closure member.
    Type: Grant
    Filed: January 14, 1986
    Date of Patent: May 19, 1987
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hager
  • Patent number: 4655241
    Abstract: An apparatus for sealing a flow control apparatus, such as a guillotine damper, is disclosed. The apparatus of the invention is particularly intended for dampers or other flow control devices utilizing pressurized sealing air to effect complete sealing. The closure member is of the type that moves completely out of the main fluid passageway when opened. Each of the two lateral seals, which cooperate with lateral edges of the closure member, includes an extended portion with a curved segment which takes the form of a cylindrical arc to stiffen each lateral seal against movement normal to the plane of the seal. This, in turn, allows considerable reduction in the clearances and gaps in the corners between the lateral seals and an entry seal to reduce the flow volume of the sealing air, to reduce the overall power requirements, and to reduce energy consumption.
    Type: Grant
    Filed: December 20, 1985
    Date of Patent: April 7, 1987
    Assignee: Damper Design, Inc.
    Inventor: Michael R. Neiman
  • Patent number: 4191212
    Abstract: A damper assembly including a plurality of damper blades pivotable about parallel axes. Each blade includes a pair of parallel plates spaced apart by supporting members, the plates providing an open fluid passageway through the blade. When the damper blades are in the closed condition, the passageways form a single enclosed space into which pressurized sealing air may be introduced to render the damper gastight with respect to gases in the main duct. In the open condition the damper blades offer very little flow resistance by allowing conduit gases to flow through the passageways between the plates of the blades.
    Type: Grant
    Filed: May 18, 1977
    Date of Patent: March 4, 1980
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hagar
  • Patent number: RE31471
    Abstract: A damper assembly including a plurality of damper blades pivotable about parallel axes. Each blade includes a pair of parallel plates spaced apart by supporting members, the plates providing an open fluid passageway through the blade. When the damper blades are in the closed condition, the passageways form a single enclosed space into which pressurized sealing air may be introduced to render the damper gastight with respect to gases in the main duct. In the open condition the damper blades offer very little flow resistance by allowing conduit gases to flow through the passageways between the plates of the blades.
    Type: Grant
    Filed: January 11, 1982
    Date of Patent: December 27, 1983
    Assignee: Damper Design, Inc.
    Inventor: Donald K. Hagar