A hybrid vehicle, an air conditioning system and a method for controlling the air conditioning system are provided. The air conditioning system includes: an electric compressor; a mechanical compressor, connected with the electric compressor in parallel; a power battery, connected with the electric compressor and configured to supply power to the electric compressor; an engine, connected with the mechanical compressor and configured to supply a power source to the mechanical compressor; an engine controller, connected with the engine and configured to start the engine when the mechanical compressor is to be started; a battery manager, connected with the power battery and configured to detect a state of charge of the power battery; and a controller, connected with the engine controller and the battery manager and configured to start the electric compressor and the mechanical compressor at different time according to the state of charge of the power battery.

An air conditioner is provided. The air conditioner may include at least one indoor device, an electric heat pump (EHP) outdoor device connected with the at least one indoor device, and having a first compressor driven using electric power and a first outdoor heat exchanger, and a gas heat pump (GHP) outdoor device connected with the at least one indoor device, and having an engine that drives a second compressor using a combustion gas and a second outdoor heat exchanger. The GHP outdoor device may include an exhaust gas heat exchanger that performs heat exchange between a refrigerant flowing through the EHP outdoor device and an exhaust gas of the engine.

A vehicle air conditioning system connector is provided. The connector includes: a first supply port, a second supply port, a first return port, a second return port, a first branch port and a second branch port.

A portable internal combustion engine system includes an internal combustion engine having a first output shaft, the internal combustion engine rotates the first output shaft; a compressor rotably engaged with the first output shaft via a belt, the first output shaft is configured to provide energy thereto; a fan coupled to the internal combustion engine to pull air into a housing; an evaporative coil in communication with the housing and to receive air from the fan; a condenser coil in communication with the housing and to receive air from the fan; and a control system to operate the compressor, the internal combustion engine, and the fan to expel cool air.

A transport refrigeration unit (26) includes a dedicated combustion engine system (56), an evaporator (50), and a de-frost heat exchanger (78) constructed and arranged to flow engine coolant in a heated state for defrosting the evaporator (50) when the dedicated combustion engine system (56) is not running. A method of operation may include running a defrost cycle of the unit (26) utilizing the heated coolant whether or not an associated internal combustion engine (66) of the unit (26) is running.

Provided is a heat-pump system including a plurality of compressors, wherein the plurality of compressors includes a first compressor and a second compressor that compress refrigerant, an oil separator provided on a discharge side of the plurality of compressors to separate oil mixed with refrigerant compressed by the plurality of compressors, an oil separation pipe extended from the oil separator to allow the plurality of compressors to recover oil, and a compressor side oil balance pipe extended from the second compressor to allow the first compressor to recover oil stored in the second compressor.

A transport refrigeration unit (30) configured to refrigerate a cargo space (26) of a vehicle in which a perishable product is stored during transport is provided including a compressor (42) having an electric compressor drive motor (58) disposed therein for operating the compressor (42). A heat rejection heat exchanger (44) and a heat absorption heat exchanger (48) are fluidly coupled to the compressor (42). At least one fan assembly (50, 54) has at least one fan that is configured to provide an air flow over at least one of the heat rejection heat exchanger (44) and the heat absorption heat exchanger (48). The transport refrigeration unit (30) is configured to operate in a first mode and a second mode. At least one onboard power source (70) is configured to produce sufficient power to operate the compressor drive motor (58) and the at least one fan (50, 54) in the first mode. An external power source (84) is configured to produce sufficient power to operate the compressor drive motor (58) and the at least one fan (50, 54) in the second mode.

A system for protecting an engine from damage due to vibration while the engine is not operating is provided. The system includes an engine having a crankshaft, at least one piston, at least one bearing, a lubricating fluid source, and a fluid pump associated therewith and a controller operationally connected to and configured to control the fluid pump. When the system is in a first mode, the controller is configured to control the fluid pump in a duty cycle to maintain a predetermined minimum fluid pressure of the lubricating fluid such that a lubricating fluid film is present between the at least one bearing and the crankshaft while the engine is not operating.

A refrigeration cycle device includes a compressor configured to compress and discharge a refrigerant containing oil, a refrigerant radiator configured to heat the ventilation air using the refrigerant discharged from the compressor as a heat source during a room interior heating, a refrigerant decompression unit configured to decompress the refrigerant having passed through the refrigerant radiator, an evaporator configured to evaporate the refrigerant and to function as a heat absorber during the room interior heating; and a controller configured to control the refrigerant decompression unit and to perform a fluctuation operation at least during the room interior heating. In the fluctuation operation, a throttle opening degree of the refrigerant decompression unit is changed such that a refrigerant state on a refrigerant outlet side of the evaporator is alternately changed to a superheated state having a superheat degree and a wet state containing the wet vapor.

A transportation refrigeration unit includes an evaporator 32 circulating a flow of refrigerant therethrough to cool a flow of supply air flowing over the evaporator. Two compressors 36,38 are in fluid communication with the evaporator to compress the flow of refrigerant and are configured and connected to operate in parallel with one another. A condenser 44 is in fluid communication with the evaporator and the two compressors. An economizer heat exchanger 56 and a suction line heat exchanger 68 are provided.