活塞式压缩机的活塞从气缸盖处开始运动时，气缸内的工作容积逐渐增大→气体即沿着进气管，推开进气阀而进入气缸，直到工作容积变到最大时为止，进气阀关闭→活塞式压缩机的活塞反向运动时，气缸内工作容积缩小，气体压力升高，当气缸内压力达到并略高于排气压力时，排气阀打开，气体排出气缸，直到活塞运动到极限位置为止，排气阀关闭。当活塞式压缩机的活塞再次反向运动时，上述过程重复出现。
When the piston of a piston compressor starts to move from the cylinder head, the working volume in the cylinder gradually increases the gas is pushed into the cylinder along the intake pipe, pushing the intake valve open until the working volume reaches its maximum. When the intake valve closes the piston of a piston compressor moves backwards, the working volume in the cylinder decreases and the air volume decreases. When the pressure in the cylinder reaches and is slightly higher than the exhaust pressure, the exhaust valve opens and the gas is discharged from the cylinder until the piston moves to the limit position, and the exhaust valve closes. When the piston of the piston compressor moves backward again, the above process repeats.