Patents by Inventor Donald E. Fritzsche

Donald E. Fritzsche 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: 6805112
    Abstract: A convection oven having multiple airflow patterns within a cooking chamber during a baking cycle. In one embodiment, at least one reversible blower wheel rotatable at varying speeds produces separate airflow states to create multiple airflow patterns within the cooking chamber during a baking cycle. In another preferred embodiment, at least one adjustable airflow control surface mounted within the cooking chamber creates multiple airflow patterns within the cooking chamber during the baking cycle.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: October 19, 2004
    Inventors: James T. Cole, Donald E. Fritzsche, David W. Harter, Ronald Jay Forni, Malcolm Reay, Jerry Sank, David McFadden, Douglas S. Jones
  • Patent number: 6557543
    Abstract: A convection oven having a high pressure duct distribution system to produce airflow within a cooking chamber of the convection oven. The high pressure airflow is easily tuned to produce a precise airflow pattern within the cooking chamber by opening and/or closing individual nozzles which extend from a duct of the duct distribution system into the cooling chamber.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: May 6, 2003
    Assignee: Gas Research Institute
    Inventors: James T. Cole, Donald E. Fritzsche, David W. Harter, Ronald Jay Forni, Malcolm Reay, Jerry Sank, David McFadden, Douglas S. Jones
  • Publication number: 20030000515
    Abstract: A convection oven having multiple airflow patterns within a cooking chamber during a baking cycle. In one embodiment, at least one reversible blower wheel rotatable at varying speeds produces separate airflow states to create multiple airflow patterns within the cooking chamber during a baking cycle. In another preferred embodiment, at least one adjustable airflow control surface mounted within the cooking chamber creates multiple airflow patterns within the cooking chamber during the baking cycle.
    Type: Application
    Filed: June 27, 2001
    Publication date: January 2, 2003
    Inventors: James T. Cole, Donald E. Fritzsche, David W. Harter, Ronald Jay Forni, Malcolm Reay, Jerry Sank, David McFadden, Douglas S. Jones
  • Publication number: 20030000513
    Abstract: A convection oven having a gas combustion system that is switchable between a direct-fired combustion system and an indirect-fired combustion system by a damper moveable between a closed position and an open position. In one preferred embodiment, a separate heat exchange element supplies combustion products to the convection oven.
    Type: Application
    Filed: June 27, 2001
    Publication date: January 2, 2003
    Inventors: James T. Cole, Donald E. Fritzsche, David W. Harter, Ronald Jay Forni, Malcolm Reay, Jerry Sank, David McFadden, Douglas S. Jones
  • Publication number: 20030000514
    Abstract: A convection oven having a high pressure duct distribution system to produce airflow within a cooking chamber of the convection oven. The high pressure airflow is easily tuned to produce a precise airflow pattern within the cooking chamber by opening and/or closing individual nozzles which extend from a duct of the duct distribution system into the cooling chamber.
    Type: Application
    Filed: June 27, 2001
    Publication date: January 2, 2003
    Inventors: James T. Cole, Donald E. Fritzsche, David W. Harter, Ronald Jay Forni, Malcolm Reay, Jerry Sank, David McFadden, Douglas S. Jones
  • Patent number: 6467402
    Abstract: A fossil fuel-fired apparatus for steaming food having at least one housing wall forming a housing, a steam chamber disposed within the housing and forming an annular space between the steam chamber and the housing wall, and at least one fossil fuel burner disposed beneath the bottom portion of the steam chamber and oriented to produce steam from water in a bottom portion of the steam chamber. Disposed within the annular space are guides for directing the hot products of combustion generated by the burners along the exterior wall surface of the steam chamber, thereby maintaining the temperature of the steam chamber walls above the temperature of the saturated steam and preventing condensation of the steam in the steam chamber.
    Type: Grant
    Filed: April 12, 2001
    Date of Patent: October 22, 2002
    Assignee: Gas Research Institute
    Inventors: Mark J. Khinkis, James T. Cole, Donald E. Fritzsche, M. Frank G. Johnson
  • Publication number: 20020148360
    Abstract: A fossil fuel-fired apparatus for steaming food having at least one housing wall forming a housing, a steam chamber disposed within the housing and forming an annular space between the steam chamber and the housing wall, and at least one fossil fuel burner disposed beneath the bottom portion of the steam chamber and oriented to produce steam from water in a bottom portion of the steam chamber. Disposed within the annular space are guides for directing the hot products of combustion generated by the burners along the exterior wall surface of the steam chamber, thereby maintaining the temperature of the steam chamber walls above the temperature of the saturated steam and preventing condensation of the steam in the steam chamber.
    Type: Application
    Filed: April 12, 2001
    Publication date: October 17, 2002
    Inventors: Mark J. Khinkis, James T. Cole, Donald E. Fritzsche, M. Frank G. Johnson
  • Patent number: 5540215
    Abstract: A method and apparatus for heating a liquid, such as cooking oil for a fryer. A heat transfer fluid, such as an oil, is heated, such as by a gas-fired burner, at a location remote from the liquid to be heated, and passed by the liquid in a heat exchange relationship, so as to more accurately control the transfer of heat into the liquid to be heated. The invention also includes an advantageous combination pivot and valve mechanism for controlling the flow of heat transfer liquid through the liquid to be heated.
    Type: Grant
    Filed: May 8, 1995
    Date of Patent: July 30, 1996
    Assignee: Gas Research Institute
    Inventors: Donald E. Fritzsche, Paul E. George
  • Patent number: 5247874
    Abstract: A gas-fired, double-sided griddle apparatus for high-volume commercial cooking comprises double-sided griddles, each having a lower platen having a horizontal lower cooking surface and an upper platen having an upper cooking surface; a positioning mechanism for moving the upper platen of each griddle into a horizontal position in contact with the food, permitting the upper platen to press downward against the food until the cooking surface reaches a predetermined level above the cooking surface of the lower platen, stopping the downward movement at that level, and lifting the upper platen away from the food after a predetermined cooking time; a counterflow heater for heating a supply of oil to desired temperatures; and apparatus for circulating the heated oil through a serpentine path wherein the oil contacts, and transfers heat to, a first region of the lower platen and a similar path wherein the oil transfers heat to a second region of the upper platen that is positioned directly above, and parallel to, the
    Type: Grant
    Filed: May 20, 1992
    Date of Patent: September 28, 1993
    Assignee: Gas Research Institute
    Inventors: Paul E. George, II, Donald E. Fritzsche, J. Douglas Dickson, John S. Barnhart
  • Patent number: 4704290
    Abstract: A recirculating-type deep fat fryer has a generally rectangular tank, a heat exchanger externally of the tank and a pump and tubing for recirculating fat from an inlet at the tank bottom, through the heat exchanger and to an outlet which is just below the upper level of fat and essentially midway between the sides of the tank. A deflector is provided adjacent the outlet to divert fat returning through the outlet along the side walls and throughout the tank to provide a "forced" horizontal convection. A pair of food-containing baskets are immersed in the fat with space between the baskets and between the outer sides of the baskets and adjacent walls of the tank. Convection results in heated fat being essentially uniformly distributed around the sides of both baskets and through the food, resulting in more uniform, even frying.
    Type: Grant
    Filed: August 8, 1985
    Date of Patent: November 3, 1987
    Assignee: Hobart Corporation
    Inventor: Donald E. Fritzsche
  • Patent number: 4684412
    Abstract: A fat recirculating system with an external, gas-heated heat exchanger for a deep fat fryer is disclosed. The use of such a system necessitates recirculation also of cleaning solution and rinse water through inaccessible plumbing of the recirculation system whenever fat is to be replaced. To remove residual water droplets from the plumbing after rinsing, a "dry cycle" is utilized. The dry cycle includes intermittent application of heating and cooling of the empty heat exchanger, resulting in a substantial reduction in start-up time when the fryer is refilled and operation again commenced.
    Type: Grant
    Filed: August 8, 1985
    Date of Patent: August 4, 1987
    Assignee: Hobart Corporation
    Inventor: Donald E. Fritzsche
  • Patent number: 4599990
    Abstract: This invention relates to a deep fat fryer of the external heat exchanger, pumped-recirculation type, and more specifically, discloses a control system for automatically heating and recirculating the fat either continuously or intermittently as needed to accommodate one or both of two conditions existing in such a fryer. First, during continuous circulation and frying vapor lock may occur at the pump impeller, inhibiting recirculation. Automatic shifting to intermittent operation is made to occur until the vapor "burps" itself from the pump. Additionally, when starting a fryer and using solid shortening, the pump and burner are operated intermittently until such time as the pump and heat exchanger are sufficiently full of melted shortening to permit continuous circulation. Upon sensing that full condition and our associated pressure, the system shifts automatically to continuous recirculation.
    Type: Grant
    Filed: August 8, 1985
    Date of Patent: July 15, 1986
    Assignees: Hobart Corporation, Thermo Electron Corporation
    Inventors: Donald E. Fritzsche, Robert A. Panora, Matthew D. Bangert