Hitachi is the patent owner of the two most popular compressor types in central air conditioning-double-rotor compressor and scroll compressor.
Now, it has been 20 years since the patent protector of double-rotor compressor, but the patent of scroll compressor is still owned by Hitachi, that is to say, not only Daikin, but also other brands are "subject" to Hitachi's patents in this respect.
The mainstream models of Hitachi in China's home improvement market are EX-PRO and MINI series. The internal machines are all universal, but the mainframe is different. The former is a rotor main engine and the latter is a scroll compressor. The former is certainly cheaper. The difference between the two compressors is that the double compressor is more efficient at 0-3P, while the scroll compressor is more efficient at 3P.