Displacement machine according to the spiral principle, method for operating a displacement machine, vehicle air-conditioning system, and vehicle

A displacement machine according to the spiral principle, in particular a scroll compressor or scroll expander, with a high-pressure chamber, a low-pressure chamber and an orbiting displacement spiral, which engages in a counter-spiral such that chambers are formed between the displacement spiral and the counter-spiral for receiving a working medium,

• wherein a counter-pressure chamber is formed between the low-pressure chamber and the displacement spiral,
• wherein a pressure regulating device which is fluidically connected to the counter-pressure chamber sets a pressure difference between the counter-pressure chamber and the low-pressure chamber by means of a set value specified by the computing unit, and
• wherein the working medium is CO2 and/or R134a and/or R1234yf and/or butane and/or ethanol and/or cyclopentan.