Patents by Inventor Andrew Hjortland

Andrew Hjortland 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).

  • Self-optimizing subcooler control
    Patent number: 10808984
    Abstract: According to certain embodiments, a method comprises determining a liquid outlet temperature setpoint for refrigerant discharged from a liquid outlet of a subcooler. The liquid outlet corresponds to a hot-side path of the subcooler that receives refrigerant directly from a tank, cools the refrigerant by an exchange of heat with a cold-side path of the subcooler that receives the refrigerant from the tank via an inlet expansion valve, and discharges the refrigerant to an evaporator via an outlet expansion valve. The method further comprises determining a superheat setpoint for the refrigerant discharged to a compressor via a vapor outlet of the cold-side path. The superheat setpoint is determined based on the liquid outlet temperature setpoint. The method further comprises adjusting a temperature of the refrigerant discharged to the compressor based on the superheat setpoint.
    Type: Grant
    Filed: January 25, 2019
    Date of Patent: October 20, 2020
    Assignee: Heatcraft Refrigeration Products LLC
    Inventor: Andrew Hjortland
  • Self-Optimizing Subcooler Control
    Publication number: 20200240698
    Abstract: According to certain embodiments, a method comprises determining a liquid outlet temperature setpoint for refrigerant discharged from a liquid outlet of a subcooler. The liquid outlet corresponds to a hot-side path of the subcooler that receives refrigerant directly from a tank, cools the refrigerant by an exchange of heat with a cold-side path of the subcooler that receives the refrigerant from the tank via an inlet expansion valve, and discharges the refrigerant to an evaporator via an outlet expansion valve. The method further comprises determining a superheat setpoint for the refrigerant discharged to a compressor via a vapor outlet of the cold-side path. The superheat setpoint is determined based on the liquid outlet temperature setpoint. The method further comprises adjusting a temperature of the refrigerant discharged to the compressor based on the superheat setpoint.
    Type: Application
    Filed: January 25, 2019
    Publication date: July 30, 2020
    Inventor: Andrew Hjortland