Patent ID: 7980119

Claim:
A cleaning method with an auto-sampler cleaning mechanism, the auto-sampler cleaning mechanism at least comprising: a sample-metering sample loop, having a sample-injecting needle at a front end thereof; a multi-ported valve; a multi-position valve; a liquid-supply valve; a diaphragm pump; and a pressure sensor and a control portion connected to the diaphragm pump for controlling the liquid supply of the diaphragm pump, the cleaning method comprising: connecting the sample-metering sample loop, the multi-ported valve, the multi-position valve, the diaphragm pump and the liquid-supply valve, so that a cleaning solution can be flowed through the liquid-supply valve, the diaphragm pump, the multi-position valve and the multi-ported valve to the sample-metering sample loop, and pumping the cleaning solution to the sample-metering sample loop by the diaphragm pump, wherein the control portion stops the liquid supply when a voltage applied to the diaphragm pump is raised but the pressure of the pressure sensor is not increased, or stops the liquid supply when a voltage applied to the diaphragm pump is dropped but the pressure is not reduced.