An expectoration system comprises an expectoration line comprising a throttling device and a balloon valve； an expectoration apparatus, comprising a main line assembly, an air pump assembly and a control system, the main line assembly comprises a fan and a shutter valve； the air pump assembly comprises a first air pump and a second air pump； the control system comprises a first sensor for measuring air pressure of the throttling device and a microcomputer control unit； the microcomputer control unit judges a patient being in an exhaling or inhaling stage through an air pressure difference detected by the first sensor, during expectoration, the first air pump supplies air to the balloon valve to disconnect a respirator air circuit, the fan and shutter valve are started to control the second air pump to supply air to the throttling device, and a respirator never stops running in the expectoration sage. The expectoration system is friendly to normal running of the respirator.一種咳痰系統，包括：包括節流裝置和球囊閥的咳痰管路；咳痰機，其包括主管路元件、氣泵元件和控制系統，主管路元件包括風機和快門閥；氣泵元件包括第一氣泵和第二氣泵；控制系統包括用於測量節流裝置處氣壓的第一感測器和微機控制單元；微機控制單元通過第一感測器檢測的氣壓差判斷病人處於呼吸或吸氣階段，咳痰時，第一氣泵向球囊閥供氣以斷開呼吸機氣路，打開風機和快門閥，控制第二氣泵向節流裝置供氣，在咳痰期間呼吸機不停止工作。本發明提出的咳痰系統不影響呼吸機的正常工作。
