Thermo King Corporation

Jeffrey B Berge

Jay L Hanson

Panayu Robert Srichai

Jayaram Seshadri

Vladimir Sulc

Stephen Anthony Kujak

Michal Kolda

Kenneth J Schultz

John Robert Sauls

Romuald M Jurewicz

Richard A Johnson

Doyle G Herrig

Robert Michael Lattin

Alan D Gustafson

James E Nixon

Lowell B Naley

David A Christiansen

Clay A Rohrer

Don Shapiro

A transport refrigeration system (TRS) includes a first heat transfer circuit including a first compressor, a condenser, a first expansion device, and a cascade heat exchanger. The first compressor, the condenser, the first expansion device, and the cascade heat exchanger are in fluid communication such that a first heat transfer fluid can flow therethrough. The TRS includes a second heat transfer circuit including a second compressor, the cascade heat exchanger, a second expansion device, and an evaporator. The second compressor, the cascade heat exchanger, the second expansion device, and the evaporator are in fluid communication such that a second heat transfer fluid can flow therethrough. The first heat transfer circuit and the second heat transfer circuit are arranged in thermal communication at the cascade heat exchanger such that the first heat transfer fluid and the second heat transfer fluid are in a heat exchange relationship at the cascade heat exchanger.

Cascade heat transfer system

A transport refrigeration system (TRS) and method of operating a TRS having a sorption subsystem are disclosed. The TRS includes a refrigeration subsystem and a sorption subsystem. The refrigeration subsystem includes a refrigerant, a compressor, a refrigerant condenser, a refrigerant expansion device, and a refrigerant evaporator in fluid communication such that the refrigerant can flow therethrough. The sorption subsystem includes a heat transfer fluid, a heat source, a boiler, a sorption condenser, a sorption expansion valve, a sorption evaporator, and a pump in fluid communication such that the heat transfer fluid can flow therethrough. The sorption evaporator is in thermal communication with the refrigeration subsystem.

Sorption system in a transport refrigeration system

The invention relates to methods of defrosting an evaporator coil of a transport refrigeration unit which includes microprocessor based electrical control. The electrical control maintains the temperature of a conditioned space at a predetermined set point temperature via hot gas heating and cooling cycles. The evaporator coil is defrosted to remove frost and ice by closing a damper to the served space and initiating a heating cycle. At the termination of defrost, a cooling cycle is initiated, but the damper is maintained in a closed position for a predetermined period of time to remove heat built up during the defrost process. The invention also detects damper malfunctions, including failure to close prior to defrost, and failure to open after defrost. The invention also evaluates manual and timed requests for a defrost operation, overriding the requests in response to predetermined conditions.

Method of operating a transport refrigeration unit

A method of operating a transport refrigeration system having a compressor driven by a prime mover at a selected one of high and low speeds, an evaporator, and an evaporator blower driven by the prime mover. Refrigeration control provides an error value which controls the temperature of a load space to a predetermined set point via heating and cooling modes. The method includes the steps of driving the compressor at high speed during pull down, and injecting hot gas into the evaporator when the error is reduced to a predetermined value. The prime mover is maintained at high speed, to keep evaporator air flow at a high rate, continuing a relatively rapid temperature pull-down across the entire load space. The speed of the prime mover is reduced to low speed when the error is further reduced to a second value, which also initiates suction line modulation while maintaining hot gas injection.

Method of operating a transport refrigeration system

A transport refrigeration system operable in cooling and heating cycles to maintain the temperature of a fresh load in a conditioned space extremely close to a predetermined set point temperature, with the cooling cycle primarily controlling the load temperature in ambients above freezing. The transport refrigeration system includes a compressor driven by a prime mover in one of two selectable speeds, an air delivery system which provides a substantially constant volume of conditioned air for a conditioned load space regardless of prime mover speed, a modulation valve in a suction line of the compressor, and a digital thermostat which senses the temperature of air returning to an evaporator. The digital thermostat controls the modulation valve via modulation control in a predetermined temperature range above and below set point, in both the heating and cooling cycles.

Transport refrigeration system with improved temperature and humidity

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Eden Prairie, MN, United States of America

Jeffrey B Berge