空调压缩机中所指定的一个齿间容积对的工作过程。阴螺杆、阳螺杆转向互相迎合一侧的气体受压缩，这一侧面称为高压区；相反，螺杆转向彼此背离的一侧面， 齿间容积在扩大并处在吸气阶段，称为低压区。这两个区域被阴螺杆、阳螺杆齿面间的接触线分隔开。可以近似地认为：两螺杆轴线所在平面是高、低压力区的分界 面。
The working process of a pair of inter tooth volumes specified in an air conditioning compressor. On the contrary, the screw turns to the side which deviates from each other, and the volume between teeth is expanding and is in the suction stage, which is called the low pressure area. The two areas are separated by the contact line between the male screw and the female screw tooth surface. It can be approximately considered that the plane where the axis of two screws is located is the interface between high and low pressure areas.
压缩制冷剂（例如氟利昂）变成液态。然后利用液态在常压下变气态时的吸热现象制冷。
A compressed refrigerant (e.g. Freon) becomes liquid. Then, the heat absorption phenomenon of liquid state changing into gas state under normal pressure is used for refrigeration.
空气密度是很小的。你拿根打针用的针管。抽满一针管空气，用手堵住出气口，推动针管就是在压缩空气了。用针管就可以把气体压缩三分之一的体积。
The air density is very small. You take a syringe. Fill a syringe with air, block the air outlet by hand, and push the needle tube to compress the air. The gas can be compressed by a third of its volume with a needle.