Abstract: An apparatus with dehumidification and defrosting abilities comprises a compressor, an indoor heat exchanger, an outdoor heat exchanger, a four-way valve and a means for refrigerant flow controlling. The compressor is coupled to the four-way valve. The four-way valve is coupled to the outdoor heat exchanger. The indoor heat exchanger is coupled to the four-way valve. The means for refrigerant flow controlling is respectively coupled to the indoor heat exchanger, the outdoor heat exchanger and the four way valve, to control mixing a low-temperature refrigerant and a high-temperature before flowing into the indoor heat exchanger, or to control mixing a low-temperature refrigerant and a high-temperature refrigerant before flowing into the compressor, or control mixing a low-temperature refrigerant and a high-temperature refrigerant before flowing into the outdoor heat exchanger.

Abstract: An evaporator, applicable to a two-stage expansion cooling system, is used for receiving a high-pressure liquid working fluid. The evaporator includes a thermal-conductive block having a channel system. The channel system includes a high-pressure channel, a low-pressure channel, and a second stage expansion channel. The second stage expansion channel has an input end and an output end. The input end is communicated with the high-pressure channel. The output end is communicated with the low-pressure channel, and has a cross-sectional area smaller than that of the low-pressure channel. The high-pressure liquid working fluid flows into the thermal-conductive block from the high-pressure channel, and then enters the second stage expansion channel through the input end. A part of the high-pressure liquid working fluid flowing out of the output end expands into a saturated low-pressure liquid working fluid and enters the low-pressure channel.

Abstract: An evaporator, applicable to a two-stage expansion cooling system, is used for receiving a high-pressure liquid working fluid. The evaporator includes a thermal-conductive block having a channel system. The channel system includes a high-pressure channel, a low-pressure channel, and a second stage expansion channel. The second stage expansion channel has an input end and an output end. The input end is communicated with the high-pressure channel. The output end is communicated with the low-pressure channel, and has a cross-sectional area smaller than that of the low-pressure channel. The high-pressure liquid working fluid flows into the thermal-conductive block from the high-pressure channel, and then enters the second stage expansion channel through the input end. A part of the high-pressure liquid working fluid flowing out of the output end expands into a saturated low-pressure liquid working fluid and enters the low-pressure channel.