Patents by Inventor Biswajit Mitra

Biswajit Mitra 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).

  • Publication number: 20240068725
    Abstract: A vapor compression system and method for operating the vapor compression system are provided. The vapor compression system includes a compressor, a condenser, and at least one check valve disposed between the compressor and the condenser. The method provides for the transmitting of a shutdown command to the compressor, the compressor including a rotating shaft and a magnetic bearing, the magnetic bearing having an active mode and an inactive mode, the magnetic bearing levitating the rotating shaft in the active mode. The method further provides for the maintaining of the magnetic bearing in the active mode during a minimum time period, the magnetic bearing switching from the active mode to the inactive mode after the minimum time period is reached.
    Type: Application
    Filed: August 31, 2022
    Publication date: February 29, 2024
    Inventors: Vishnu Sishtla, Scott A. Nieforth, Biswajit Mitra, Macey Parrott, Puja Chopra
  • Patent number: 11635240
    Abstract: A separator for removing contamination from a fluid of a heat pump includes a housing having a hollow interior, a header plate arranged within the hollow interior and having at least one mounting hole, and a separation module mounted within the hollow interior. The separation module includes a connector for forming an interface with the at least one mounting hole. A sealant is located at the interface between the connector and the mounting hole.
    Type: Grant
    Filed: May 8, 2020
    Date of Patent: April 25, 2023
    Assignee: CARRIER CORPORATION
    Inventors: Rajiv Ranjan, Parmesh Verma, Haralambos Cordatos, Biswajit Mitra, Subhrajit Chakraborty, Ying She
  • Publication number: 20230053834
    Abstract: A refrigeration system includes a compressor, a heat rejecting heat exchanger, an expansion device, and a heat absorbing heat exchanger fluidly connected to form a closed loop through which a refrigerant is configured to circulate. An economizer heat exchanger is located downstream from an outlet of the heat rejecting heat exchanger and upstream from the expansion device relative to a flow of the refrigerant. The economizer heat exchanger has a main flow path and an economizer flow path formed therein. All liquid refrigerant provided at an outlet of the heat rejecting heat exchanger is provided to the main flow path.
    Type: Application
    Filed: August 17, 2022
    Publication date: February 23, 2023
    Inventors: Biswajit Mitra, Hsihua Li
  • Publication number: 20230056234
    Abstract: A vapor compression system including: a condenser; an evaporator; and an expansion control system on the main flowpath between the condenser and the evaporator, wherein the expansion control system further includes: one or more electronic expansion valves; and a modulated ball valve.
    Type: Application
    Filed: August 17, 2022
    Publication date: February 23, 2023
    Inventors: Biswajit Mitra, Hsihua Li, Macey Parrott, Prashant Patel
  • Patent number: 11499756
    Abstract: A hydronic economizer module configured for use in a chiller system having a vapor compression cycle including a housing having at least a first air inlet. A heat exchanger assembly located within said housing. The heat exchanger includes at least one heat exchanger coil. A fan assembly includes at least one fan generally aligned with the at least one heat exchanger coil. At least one valve is movable between a plurality of positions to control a flow of fluid into said heat exchanger assembly. When said at least one valve is in a first position the economizer module is arranged in parallel with a component of the vapor compression cycle. When said at least one valve is in a second position the economizer module is arranged in series with said component of the vapor compression cycle.
    Type: Grant
    Filed: April 5, 2018
    Date of Patent: November 15, 2022
    Assignee: CARRIER CORPORATION
    Inventors: Frank Silva, Biswajit Mitra, Richard G Lord
  • Patent number: 11460024
    Abstract: A method of monitoring a volume index valve of a compressor is provided. The method includes recording a first reading of an operating condition of the compressor when the volume index valve is in a first position. The method also includes switching the volume index valve to a second position. The method further includes recording a second reading of the operating condition of the compressor when the volume index valve is in the second position. The method yet further includes calculating a difference between the first reading and the second reading. The method also includes comparing the difference to a predetermined threshold difference to determine if the volume index valve is moving between the first position and the second position in a desired manner.
    Type: Grant
    Filed: August 1, 2017
    Date of Patent: October 4, 2022
    Assignee: CARRIER CORPORATION
    Inventors: Tyler Joseph Ludwig, Biswajit Mitra
  • Publication number: 20220057125
    Abstract: A separator for removing contamination from a fluid of a heat pump includes a housing having a hollow interior, a header plate arranged within the hollow interior and having at least one mounting hole, and a separation module mounted within the hollow interior. The separation module includes a connector for forming an interface with the at least one mounting hole. A sealant is located at the interface between the connector and the mounting hole.
    Type: Application
    Filed: May 8, 2020
    Publication date: February 24, 2022
    Inventors: Rajiv Ranjan, Parmesh Verma, Haralambos Cordatos, Biswajit Mitra, Subhrajit Chakraborty, Ying She
  • Publication number: 20210381505
    Abstract: A method of monitoring a volume index valve of a compressor is provided. The method includes recording a first reading of an operating condition of the compressor when the volume index valve is in a first position. The method also includes switching the volume index valve to a second position. The method further includes recording a second reading of the operating condition of the compressor when the volume index valve is in the second position. The method yet further includes calculating a difference between the first reading and the second reading. The method also includes comparing the difference to a predetermined threshold difference to determine if the volume index valve is moving between the first position and the second position in a desired manner.
    Type: Application
    Filed: August 1, 2017
    Publication date: December 9, 2021
    Inventors: Tyler Joseph Ludwig, Biswajit Mitra
  • Publication number: 20210262705
    Abstract: A hydronic economizer module is configured for use in a chiller system that has a vapor compression cycle. The hydronic economizer module includes a heat exchanger assembly located within a housing having at least one heat exchanger coil, a fan assembly having at least one fan generally aligned with at least one heat exchanger coil, and at least one valve is movable between a plurality of positions to control a flow of fluid into the heat exchanger assembly. When the at least one valve is in a first position, the economizer module is arranged in parallel with a flat plate heat exchanger. When the at least one valve is in a second position, the economizer module is arranged in series with the flat plate heat exchanger. The flat plate heat exchanger includes at least one fluid port for communicating with a component of the vapor compression cycle.
    Type: Application
    Filed: May 12, 2020
    Publication date: August 26, 2021
    Inventors: Frank Silva, Biswajit Mitra, Richard G. Lord
  • Publication number: 20210088260
    Abstract: A hydronic economizer module configured for use in a chiller system having a vapor compression cycle including a in housing having at least a first air inlet. A heat exchanger assembly located within said housing. The heat exchanger includes at least one heat exchanger coil. A fan assembly includes at least one fan generally aligned with the at least one heat exchanger coil. At least one valve is movable between a plurality of positions to control a flow of fluid into said heat exchanger assembly. When said at least one valve is in a first position the economizer module is arranged in parallel with a component of the vapor compression cycle. When said at least one valve is in a second position the economizer module is arranged in series with said component of the vapor compression cycle.
    Type: Application
    Filed: April 5, 2018
    Publication date: March 25, 2021
    Inventors: Frank Silva, Biswajit Mitra, Richard G Lord
  • Patent number: 9951975
    Abstract: A carbon dioxide refrigerant vapor compression system and method of operating that system are provided. The refrigerant vapor compression system includes a compression device, a flash tank receiver disposed in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger, and a compressor unload circuit including a refrigerant line establishing refrigerant flow communication between an intermediate pressure stage of the compression device and the refrigerant circuit at a location downstream of the refrigerant heat absorption heat exchanger and upstream of a suction inlet to the compression device, and a unload circuit flow control device disposed in said unload circuit refrigerant line. In response to at least one system operating parameter sensed by at least one sensor, the controller selectively positions the unload flow control device to maintain the refrigerant vapor compression system operating below a preselected high pressure limit.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: April 24, 2018
    Assignee: CARRIER CORPORATION
    Inventors: Yu H. Chen, Suresh Duraisamy, Lucy Yi Liu, Jason Scarcella, Zvonko Asprovski, Kursten Lamendola, Biswajit Mitra
  • Patent number: 8671703
    Abstract: A refrigerant vapor compression system includes a flash tank disposed in series refrigerant flow relationship in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger. A primary expansion valve is interdisposed in the refrigerant circuit upstream of the refrigerant heat absorption heat exchanger and a secondary expansion valve is interdisposed in the refrigerant circuit upstream of the flash tank. A refrigerant vapor line is provided to direct refrigerant vapor from the flash tank to an intermediate pressure stage of the compression process. A refrigerant-to-refrigerant heat exchanger operates to transfer heat from refrigerant flowing through the primary refrigerant circuit to refrigerant flowing through the refrigerant vapor line.
    Type: Grant
    Filed: May 14, 2007
    Date of Patent: March 18, 2014
    Assignee: Carrier Corporation
    Inventors: Biswajit Mitra, Yu H. Chen
  • Patent number: 8561425
    Abstract: A refrigerant vapor compression system includes a flash tank economizer and a refrigerant-to-refrigerant heat exchanger economizer disposed in series refrigerant flow relationship in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger. A primary expansion valve disposed in the refrigerant circuit in operative association with and upstream of the refrigerant heat absorption heat exchanger and an economizer expansion valve disposed in the refrigerant circuit in operative association and upstream of the flash tank economizer provide a two-step expansion process for expanding refrigerant passing through the refrigerant circuit from the refrigerant heat rejection heat exchanger to the refrigerant heat absorption heat exchanger.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: October 22, 2013
    Assignee: Carrier Corporation
    Inventors: Biswajit Mitra, Yu H. Chen
  • Patent number: 8459052
    Abstract: A refrigerant vapor compression system includes a flash tank receiver disposed in the refrigerant circuit intermediate the refrigerant cooling heat exchanger and the refrigerant heating heat exchanger. The flash tank receiver, which receives a liquid/vapor refrigerant mix, also functions as a receiver. A refrigerant charge control apparatus includes at least one sensor for sensing an operating characteristic of the refrigerant circulating through the refrigerant compression device, and a controller operative to selectively adjust a secondary expansion device to increase or decrease the flow of refrigerant passing into the flash tank receiver to provide a circulating refrigerant charge consistent with maintaining a desired system operating characteristic.
    Type: Grant
    Filed: January 12, 2011
    Date of Patent: June 11, 2013
    Assignee: Carrier Corporation
    Inventors: James W. Bush, Wayne P. Beagle, Biswajit Mitra
  • Patent number: 8424326
    Abstract: A refrigerant vapor compression system includes a flash tank economizer defining a separation chamber is disposed in the refrigerant circuit intermediate a refrigerant heat rejection heat exchanger and a refrigerant heat absorption heat exchanger. A primary expansion valve is interdisposed in the refrigerant circuit in operative association with and upstream of the refrigerant heat absorption heat exchanger and a secondary expansion valve is interdisposed in the refrigerant circuit in operative association and upstream of the flash tank economizer. A refrigerant vapor injection line establishes refrigerant flow communication between an upper portion of the separation chamber and an intermediate pressure stage of the system's compression device and a suction pressure portion of the refrigerant circuit.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: April 23, 2013
    Assignee: Carrier Corporation
    Inventors: Biswajit Mitra, Yu H. Chen, Jason Scarcella, Suresh Duraisamy, Lucy Yi Liu
  • Patent number: 8418482
    Abstract: A refrigeration system (20A) comprises an evaporator (27), a two-stage compressor (32) for compressing a refrigerant, a second compressor (34) for compressing the refrigerant, a heat rejecting heat exchanger (24) for cooling the refrigerant, a first economizer circuit (25A), and a second economizer circuit (25B). The first economizer circuit (25A) is configured to inject refrigerant into an interstage port (48) of the two-stage compressor (32). The second economizer circuit (25B) is connected to the second compressor (34).
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: April 16, 2013
    Assignee: Carrier Corporation
    Inventors: James W. Bush, Wayne P. Beagle, Biswajit Mitra
  • Patent number: 8322150
    Abstract: A refrigeration system (20A) comprises an evaporator (27) for evaporating a refrigerant, a two-stage compressor (32) for compressing the refrigerant, a single-stage compressor (34) for compressing the refrigerant, a heat rejecting heat exchanger (24) for cooling the refrigerant, a first economizer circuit (25A), and a second economizer circuit (25B). The first economizer circuit (25A) is configured to inject refrigerant into an interstage port (48) of the two-stage compressor (32). The second economizer circuit (25B) is configured to inject refrigerant into a suction port (52) of the single-stage compressor (34). The single-stage compressor (34) is configured to discharge into the interstage port (48) of the two-stage compressor (32).
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: December 4, 2012
    Assignee: Carrier Corporation
    Inventors: Biswajit Mitra, Wayne P. Beagle, James W. Bush
  • Patent number: 8196421
    Abstract: A method for controlling temperature pulldown of an enclosure with a refrigeration system having a compressor, a heat rejecting heat exchanger, an expansion valve, and an evaporator comprises circulating a refrigerant through the refrigeration system, sensing a parameter of the enclosure, determining a desired evaporator pressure based upon the parameter sensed, and adjusting the expansion valve as a function of the desired evaporator pressure.
    Type: Grant
    Filed: June 1, 2006
    Date of Patent: June 12, 2012
    Assignee: Carrier Corporation
    Inventors: James W. Bush, Wayne P. Beagle, Biswajit Mitra
  • Publication number: 20120117988
    Abstract: A refrigeration system (20A) comprises an evaporator (27), a plurality of compressors (32, 34, 35) for compressing a refrigerant, a heat rejecting heat exchanger (24) for cooling the refrigerant, and a plurality of economizer heat exchangers (28A, 28B). Each of the economizer heat exchangers (28A, 28B) is configured to inject a portion of the refrigerant into a suction port (52, 56) of one of the compressors (34, 35).
    Type: Application
    Filed: March 27, 2006
    Publication date: May 17, 2012
    Applicant: Carrier Corporation
    Inventors: Biswajit Mitra, Wayne P. Beagle, James W. Bush
  • Publication number: 20120011866
    Abstract: A refrigerant vapor compression system includes a hot gas bypass line establishing refrigerant vapor flow communication between the compression device and the refrigerant heat absorption heat exchanger, and bypassing the refrigerant heat rejection heat exchanger and the primary expansion device. A refrigerant vapor flow control device is interdisposed in the hot gas bypass line. The flow control device has at least a first open position in which refrigerant vapor flow may pass through the hot gas bypass line and a closed position in which refrigerant vapor flow may not pass through the hot gas bypass line.
    Type: Application
    Filed: April 6, 2010
    Publication date: January 19, 2012
    Applicant: Carrier Corporation
    Inventors: Jason Scarcella, Alexander Lifson, Daqing Li, Biswajit Mitra, Lucy Yi Liu, Suresh Duraisamy, Yu H. Chen