US Patent 7195229 Automatic sampler

In a direct injection type automatic sampler, a sampling needle having a liquid sample collected from a sample vessel by using suction force of a pump is inserted into an injection port. Then, a flow path-switching valve is rotated to switch a flow path to make a flow of mobile phase liquid pass through a loop to thereby introduce the collected sample into a column. The injection port is directly incorporated in the flow path-switching valve.